chore: bump version to 0.3.0

- Disable noisy biome rules (noExplicitAny, useExhaustiveDependencies, etc.)
- Fix memory leak in file-preview-list.tsx with useRef pattern
- Separate unmount cleanup into dedicated useEffect
- Add ToolPartLike interface for type safety in chat-message-display
- Add accessibility attributes (role, tabIndex, onKeyDown)
- Replace autoFocus with useEffect focus pattern
- Minor syntax improvements (optional chaining, key fixes)

.dockerignore

@@ -0,0 +1,60 @@
+# Dependencies
+node_modules
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+
+# Build output
+.next
+out
+dist
+build
+
+# Testing
+coverage
+.nyc_output
+
+# Environment variables
+.env
+.env*.local
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+# Git
+.git
+.gitignore
+.gitattributes
+
+# IDE
+.vscode
+.idea
+*.swp
+*.swo
+*~
+
+# Operating System
+.DS_Store
+Thumbs.db
+
+# Documentation
+README.md
+*.md
+!env.example
+
+# CI/CD
+.github
+.gitlab-ci.yml
+.travis.yml
+
+# Docker
+Dockerfile
+.dockerignore
+docker-compose*.yml
+
+# Other
+*.log
+.cache
+.turbo
+

.eslintrc.json

@@ -0,0 +1,3 @@
+{
+    "extends": ["next/core-web-vitals", "next/typescript"]
+}

.github/FUNDING.yml

@@ -0,0 +1,15 @@
+# These are supported funding model platforms
+
+github: dayuanjiang
+patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: # Replace with a single Ko-fi username
+tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
+polar: # Replace with a single Polar username
+buy_me_a_coffee: # Replace with a single Buy Me a Coffee username
+thanks_dev: # Replace with a single thanks.dev username
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.github/workflows/claude-code.yml

@@ -1,113 +0,0 @@
-name: Claude Code
-
-on:
-  issue_comment:
-    types: [created]
-  pull_request_review_comment:
-    types: [created]
-  issues:
-    types: [opened, assigned]
-  pull_request_review:
-    types: [submitted]
-  pull_request_target:
-    types: [opened, synchronize, reopened]
-
-jobs:
-  claude:
-    if: |
-      (github.event_name == 'issue_comment' && contains(github.event.comment.body, '@claude')) ||
-      (github.event_name == 'pull_request_review_comment' && contains(github.event.comment.body, '@claude')) ||
-      (github.event_name == 'pull_request_review' && contains(github.event.review.body, '@claude')) ||
-      (github.event_name == 'issues' && contains(github.event.issue.body, '@claude'))
-    runs-on: ubuntu-latest
-    permissions:
-      contents: write
-      pull-requests: write
-      issues: write
-      id-token: write
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Configure AWS Credentials
-        uses: aws-actions/configure-aws-credentials@v4
-        with:
-          role-to-assume: ${{ secrets.AWS_ROLE_TO_ASSUME }}
-          aws-region: us-east-1
-
-      - name: Run Claude Code
-        uses: anthropics/claude-code-action@v1
-        with:
-          use_bedrock: "true"
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-
-  pr-review:
-    if: github.event_name == 'pull_request_target'
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      pull-requests: write
-      id-token: write
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Configure AWS Credentials
-        uses: aws-actions/configure-aws-credentials@v4
-        with:
-          role-to-assume: ${{ secrets.AWS_ROLE_TO_ASSUME }}
-          aws-region: us-east-1
-
-      - name: Run Claude Code PR Review
-        uses: anthropics/claude-code-action@v1
-        with:
-          use_bedrock: "true"
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          allowed_non_write_users: "*"
-          prompt: |
-            REPO: ${{ github.repository }}
-            PR NUMBER: ${{ github.event.pull_request.number }}
-
-            This is a personal project - an AI-powered draw.io diagram generator built with:
-            - Next.js 15 with React 19
-            - Vercel AI SDK (streamText, useChat, tool calling)
-            - Multiple AI providers: Bedrock, Anthropic, OpenAI, Google, Azure, OpenRouter, Ollama
-
-            First, check previous review comments from github-actions bot using `gh api repos/${{ github.repository }}/pulls/${{ github.event.pull_request.number }}/comments`.
-            For each previous comment:
-            - If the issue is fixed in the current code, resolve the comment thread using:
-              `gh api graphql -f query='mutation { resolveReviewThread(input: {threadId: "THREAD_ID"}) { thread { isResolved } } }'`
-              Get the thread ID from the comment's node_id field.
-            - If the issue still exists, leave it alone
-
-            Then review the current diff for NEW issues only:
-
-            Review this PR for ONLY these issues:
-            1. Bugs that would cause runtime errors or broken functionality
-            2. Security issues (exposed secrets, API key leaks)
-            3. AI SDK misuse - specifically check for:
-               - Client-side: Should use useChat/useCompletion/useObject hooks, NOT raw fetch()
-               - Server-side: Should use streamText/generateText/streamObject/generateObject
-               - Message handling: Access message.parts array, not legacy content property
-               - Tool definitions: Must use Zod schemas for inputSchema
-               - Status handling: Check status (submitted/streaming/ready/error) before actions
-               - Stream cleanup: Call stop() when aborting streams
-
-            When reviewing AI SDK usage, fetch https://ai-sdk.dev/docs/ to verify correct patterns.
-            Key doc pages: /docs/ai-sdk-ui/chatbot, /docs/ai-sdk-core/generating-text, /docs/ai-sdk-core/tools-and-tool-calling
-
-            DO NOT comment on:
-            - Performance optimizations
-            - Code style or formatting
-            - "Best practices" that don't affect functionality
-            - Type safety improvements
-            - Error handling additions
-
-            Use `mcp__github_inline_comment__create_inline_comment` for inline comments.
-            Be very selective - if there are no real bugs, just say "LGTM" in a PR comment.
-          claude_args: |
-            --allowedTools "mcp__github_inline_comment__create_inline_comment,Bash(gh pr comment:*),Bash(gh pr diff:*),Bash(gh pr view:*),Bash(gh api:*),WebFetch(domain:ai-sdk.dev)"

.github/workflows/docker-build.yml

@@ -0,0 +1,66 @@
+name: Docker Build and Push
+
+on:
+  push:
+    branches:
+      - main
+      - master
+      - dev
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - main
+      - master
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+      
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to GitHub Container Registry
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels)
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+            type=sha,prefix=sha-
+            type=raw,value=latest,enable={{is_default_branch}}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+          platforms: linux/amd64,linux/arm64
+

.gitignore

@@ -41,3 +41,4 @@ yarn-error.log*
 next-env.d.ts
 push-via-ec2.sh
 .claude/settings.local.json
+.playwright-mcp/

.husky/pre-commit

@@ -0,0 +1 @@
+npx lint-staged

.vscode/settings.json

@@ -0,0 +1,23 @@
+{
+    "editor.formatOnSave": true,
+    "editor.defaultFormatter": "biomejs.biome",
+    "editor.codeActionsOnSave": {
+        "source.fixAll.biome": "explicit",
+        "source.organizeImports.biome": "explicit"
+    },
+    "[javascript]": {
+        "editor.defaultFormatter": "biomejs.biome"
+    },
+    "[typescript]": {
+        "editor.defaultFormatter": "biomejs.biome"
+    },
+    "[javascriptreact]": {
+        "editor.defaultFormatter": "biomejs.biome"
+    },
+    "[typescriptreact]": {
+        "editor.defaultFormatter": "biomejs.biome"
+    },
+    "[json]": {
+        "editor.defaultFormatter": "biomejs.biome"
+    }
+}

CONTRIBUTING.md

@@ -0,0 +1,35 @@
+# Contributing
+
+## Setup
+
+```bash
+git clone https://github.com/YOUR_USERNAME/next-ai-draw-io.git
+cd next-ai-draw-io
+npm install
+cp env.example .env.local
+npm run dev
+```
+
+## Code Style
+
+We use [Biome](https://biomejs.dev/) for linting and formatting:
+
+```bash
+npm run format   # Format code
+npm run lint     # Check lint errors
+npm run check    # Run all checks (CI)
+```
+
+Pre-commit hooks via Husky will run Biome automatically on staged files.
+
+For a better experience, install the [Biome VS Code extension](https://marketplace.visualstudio.com/items?itemName=biomejs.biome) for real-time linting and format-on-save.
+
+## Pull Requests
+
+1. Create a feature branch
+2. Make changes and ensure `npm run check` passes
+3. Submit PR against `main` with a clear description
+
+## Issues
+
+Include steps to reproduce, expected vs actual behavior, and AI provider used.

Dockerfile

@@ -0,0 +1,55 @@
+# Multi-stage Dockerfile for Next.js
+
+# Stage 1: Install dependencies
+FROM node:20-alpine AS deps
+RUN apk add --no-cache libc6-compat
+WORKDIR /app
+
+# Copy package files
+COPY package.json package-lock.json* ./
+
+# Install dependencies
+RUN npm ci
+
+# Stage 2: Build application
+FROM node:20-alpine AS builder
+WORKDIR /app
+
+# Copy node_modules from deps stage
+COPY --from=deps /app/node_modules ./node_modules
+COPY . .
+
+# Disable Next.js telemetry during build
+ENV NEXT_TELEMETRY_DISABLED=1
+
+# Build Next.js application (standalone mode)
+RUN npm run build
+
+# Stage 3: Production runtime
+FROM node:20-alpine AS runner
+WORKDIR /app
+
+ENV NODE_ENV=production
+ENV NEXT_TELEMETRY_DISABLED=1
+
+# Create non-root user for security
+RUN addgroup --system --gid 1001 nodejs
+RUN adduser --system --uid 1001 nextjs
+
+# Copy necessary files
+COPY --from=builder /app/public ./public
+
+# Copy standalone build output
+COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
+COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
+
+USER nextjs
+
+EXPOSE 3000
+
+ENV PORT=3000
+ENV HOSTNAME="0.0.0.0"
+
+# Start the application
+CMD ["node", "server.js"]
+

LICENSE

@@ -0,0 +1,190 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
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+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
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+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
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+
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+      transformation or translation of a Source form, including but
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+
+      "Work" shall mean the work of authorship, whether in Source or
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+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
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+      communication on electronic mailing lists, source code control systems,
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+      designated in writing by the copyright owner as "Not a Contribution."
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+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
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+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
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+      where such license applies only to those patent claims licensable
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+      institute patent litigation against any entity (including a
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+      or a Contribution incorporated within the Work constitutes direct
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+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
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+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
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+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   Copyright 2024 Dayuan Jiang
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

README.md

@@ -1,11 +1,24 @@
 # Next AI Draw.io
 
-A next.js web application that integrates AI capabilities with draw.io diagrams. This app allows you to create, modify, and enhance diagrams through natural language commands and AI-assisted visualization.
+<div align="center">
+
+**AI-Powered Diagram Creation Tool - Chat, Draw, Visualize**
+
+English | [中文](./README_CN.md) | [日本語](./README_JA.md)
+
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![Next.js](https://img.shields.io/badge/Next.js-15.x-black)](https://nextjs.org/)
+[![TypeScript](https://img.shields.io/badge/TypeScript-5.x-blue)](https://www.typescriptlang.org/)
+[![Sponsor](https://img.shields.io/badge/Sponsor-❤-ea4aaa)](https://github.com/sponsors/DayuanJiang)
+
+[🚀 Live Demo](https://next-ai-drawio.jiang.jp/)
+
+</div>
+
+A Next.js web application that integrates AI capabilities with draw.io diagrams. Create, modify, and enhance diagrams through natural language commands and AI-assisted visualization.
 
 https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
 
-Demo site: [https://next-ai-draw-io.vercel.app](https://next-ai-draw-io.vercel.app)
-
 ## Features
 
 -   **LLM-Powered Diagram Creation**: Leverage Large Language Models to create and manipulate draw.io diagrams directly through natural language commands
@@ -21,6 +34,13 @@ Here are some example prompts and their generated diagrams:
 
 <div align="center">
 <table width="100%">
+  <tr>
+    <td colspan="2" valign="top" align="center">
+      <strong>Animated transformer connectors</strong><br />
+      <p><strong>Prompt:</strong> Give me a **animated connector** diagram of transformer's architecture.</p>
+      <img src="./public/animated_connectors.svg" alt="Transformer Architecture with Animated Connectors" width="480" />
+    </td>
+  </tr>
   <tr>
     <td width="50%" valign="top">
       <strong>GCP architecture diagram</strong><br />
@@ -40,16 +60,9 @@ Here are some example prompts and their generated diagrams:
       <img src="./public/azure_demo.svg" alt="Azure Architecture Diagram" width="480" />
     </td>
     <td width="50%" valign="top">
-      <strong>Animated transformer connectors</strong><br />
-      <p><strong>Prompt:</strong> Give me a **animated connector** diagram of transformer's architecture.</p>
-      <img src="./public/animated_connectors.svg" alt="Transformer Architecture with Animated Connectors" width="480" />
-    </td>
-  </tr>
-  <tr>
-    <td colspan="2" valign="top" align="center">
       <strong>Cat sketch prompt</strong><br />
       <p><strong>Prompt:</strong> Draw a cute cat for me.</p>
-      <img src="./public/cat_demo.svg" alt="Cat Drawing" width="260" />
+      <img src="./public/cat_demo.svg" alt="Cat Drawing" width="240" />
     </td>
   </tr>
 </table>
@@ -60,7 +73,7 @@ Here are some example prompts and their generated diagrams:
 The application uses the following technologies:
 
 -   **Next.js**: For the frontend framework and routing
--   **@ai-sdk/react**: For the chat interface and AI interactions
+-   **Vercel AI SDK** (`ai` + `@ai-sdk/*`): For streaming AI responses and multi-provider support
 -   **react-drawio**: For diagram representation and manipulation
 
 Diagrams are represented as XML that can be rendered in draw.io. The AI processes your commands and generates or modifies this XML accordingly.
@@ -68,16 +81,44 @@ Diagrams are represented as XML that can be rendered in draw.io. The AI processe
 ## Multi-Provider Support
 
 -   AWS Bedrock (default)
--   OpenAI / OpenAI-compatible APIs (via `OPENAI_BASE_URL`)
+-   OpenAI
 -   Anthropic
 -   Google AI
 -   Azure OpenAI
 -   Ollama
+-   OpenRouter
+-   DeepSeek
+
+All providers except AWS Bedrock and OpenRouter support custom endpoints.
+
+📖 **[Detailed Provider Configuration Guide](./docs/ai-providers.md)** - See setup instructions for each provider.
+
+**Model Requirements**: This task requires strong model capabilities for generating long-form text with strict formatting constraints (draw.io XML). Recommended models include Claude Sonnet 4.5, GPT-4o, Gemini 2.0, and DeepSeek V3/R1.
 
 Note that `claude-sonnet-4-5` has trained on draw.io diagrams with AWS logos, so if you want to create AWS architecture diagrams, this is the best choice.
 
 ## Getting Started
 
+### Run with Docker (Recommended)
+
+If you just want to run it locally, the best way is to use Docker.
+
+First, install Docker if you haven't already: [Get Docker](https://docs.docker.com/get-docker/)
+
+Then run:
+
+```bash
+docker run -d -p 3000:3000 \
+  -e AI_PROVIDER=openai \
+  -e AI_MODEL=gpt-4o \
+  -e OPENAI_API_KEY=your_api_key \
+  ghcr.io/dayuanjiang/next-ai-draw-io:latest
+```
+
+Open [http://localhost:3000](http://localhost:3000) in your browser.
+
+Replace the environment variables with your preferred AI provider configuration. See [Multi-Provider Support](#multi-provider-support) for available options.
+
 ### Installation
 
 1. Clone the repository:
@@ -105,11 +146,14 @@ cp env.example .env.local
 
 Edit `.env.local` and configure your chosen provider:
 
--   Set `AI_PROVIDER` to your chosen provider (bedrock, openai, anthropic, google, azure, ollama)
+-   Set `AI_PROVIDER` to your chosen provider (bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek)
 -   Set `AI_MODEL` to the specific model you want to use
 -   Add the required API keys for your provider
+-   `ACCESS_CODE_LIST`: Optional access password(s), can be comma-separated for multiple passwords.
 
-See the [Multi-Provider Support](#multi-provider-support) section above for provider-specific configuration examples.
+> Warning: If you do not set `ACCESS_CODE_LIST`, anyone can access your deployed site directly, which may lead to rapid depletion of your token. It is recommended to set this option.
+
+See the [Provider Configuration Guide](./docs/ai-providers.md) for detailed setup instructions for each provider.
 
 4. Run the development server:
 
@@ -133,14 +177,19 @@ Be sure to **set the environment variables** in the Vercel dashboard as you did
 ## Project Structure
 
 ```
-app/                  # Next.js application routes and pages
-  extract_xml.ts      # Utilities for XML processing
+app/                  # Next.js App Router
+  api/chat/           # Chat API endpoint with AI tools
+  page.tsx            # Main page with DrawIO embed
 components/           # React components
-  chat-input.tsx      # User input component for AI interaction
-  chatPanel.tsx       # Chat interface with diagram control
+  chat-panel.tsx      # Chat interface with diagram control
+  chat-input.tsx      # User input component with file upload
+  history-dialog.tsx  # Diagram version history viewer
   ui/                 # UI components (buttons, cards, etc.)
+contexts/             # React context providers
+  diagram-context.tsx # Global diagram state management
 lib/                  # Utility functions and helpers
-  utils.ts            # General utilities including XML conversion
+  ai-providers.ts     # Multi-provider AI configuration
+  utils.ts            # XML processing and conversion utilities
 public/               # Static assets including example images
 ```
 
@@ -149,16 +198,19 @@ public/               # Static assets including example images
 -   [x] Allow the LLM to modify the XML instead of generating it from scratch everytime.
 -   [x] Improve the smoothness of shape streaming updates.
 -   [x] Add multiple AI provider support (OpenAI, Anthropic, Google, Azure, Ollama)
--   [ ] Solve the bug that generation will fail for session that longer than 60s.
-
-## License
-
-This project is licensed under the MIT License.
+-   [x] Solve the bug that generation will fail for session that longer than 60s.
+-   [ ] Add API config on the UI.
 
 ## Support & Contact
 
+If you find this project useful, please consider [sponsoring](https://github.com/sponsors/DayuanJiang) to help me host the live demo site!
+
 For support or inquiries, please open an issue on the GitHub repository or contact the maintainer at:
 
 -   Email: me[at]jiang.jp
 
+## Star History
+
+[![Star History Chart](https://api.star-history.com/svg?repos=DayuanJiang/next-ai-draw-io&type=date&legend=top-left)](https://www.star-history.com/#DayuanJiang/next-ai-draw-io&type=date&legend=top-left)
+
 ---

README_CN.md

@@ -0,0 +1,216 @@
+# Next AI Draw.io
+
+<div align="center">
+
+**AI驱动的图表创建工具 - 对话、绘制、可视化**
+
+[English](./README.md) | 中文 | [日本語](./README_JA.md)
+
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![Next.js](https://img.shields.io/badge/Next.js-15.x-black)](https://nextjs.org/)
+[![TypeScript](https://img.shields.io/badge/TypeScript-5.x-blue)](https://www.typescriptlang.org/)
+[![Sponsor](https://img.shields.io/badge/Sponsor-❤-ea4aaa)](https://github.com/sponsors/DayuanJiang)
+
+[🚀 在线演示](https://next-ai-drawio.jiang.jp/)
+
+</div>
+
+一个集成了AI功能的Next.js网页应用，与draw.io图表无缝结合。通过自然语言命令和AI辅助可视化来创建、修改和增强图表。
+
+https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
+
+## 功能特性
+
+-   **LLM驱动的图表创建**：利用大语言模型通过自然语言命令直接创建和操作draw.io图表
+-   **基于图像的图表复制**：上传现有图表或图像，让AI自动复制和增强
+-   **图表历史记录**：全面的版本控制，跟踪所有更改，允许您查看和恢复AI编辑前的图表版本
+-   **交互式聊天界面**：与AI实时对话来完善您的图表
+-   **AWS架构图支持**：专门支持生成AWS架构图
+-   **动画连接器**：在图表元素之间创建动态动画连接器，实现更好的可视化效果
+
+## **示例**
+
+以下是一些示例提示词及其生成的图表：
+
+<div align="center">
+<table width="100%">
+  <tr>
+    <td colspan="2" valign="top" align="center">
+      <strong>动画Transformer连接器</strong><br />
+      <p><strong>提示词：</strong> 给我一个带有**动画连接器**的Transformer架构图。</p>
+      <img src="./public/animated_connectors.svg" alt="带动画连接器的Transformer架构" width="480" />
+    </td>
+  </tr>
+  <tr>
+    <td width="50%" valign="top">
+      <strong>GCP架构图</strong><br />
+      <p><strong>提示词：</strong> 使用**GCP图标**生成一个GCP架构图。在这个图中，用户连接到托管在实例上的前端。</p>
+      <img src="./public/gcp_demo.svg" alt="GCP架构图" width="480" />
+    </td>
+    <td width="50%" valign="top">
+      <strong>AWS架构图</strong><br />
+      <p><strong>提示词：</strong> 使用**AWS图标**生成一个AWS架构图。在这个图中，用户连接到托管在实例上的前端。</p>
+      <img src="./public/aws_demo.svg" alt="AWS架构图" width="480" />
+    </td>
+  </tr>
+  <tr>
+    <td width="50%" valign="top">
+      <strong>Azure架构图</strong><br />
+      <p><strong>提示词：</strong> 使用**Azure图标**生成一个Azure架构图。在这个图中，用户连接到托管在实例上的前端。</p>
+      <img src="./public/azure_demo.svg" alt="Azure架构图" width="480" />
+    </td>
+    <td width="50%" valign="top">
+      <strong>猫咪素描</strong><br />
+      <p><strong>提示词：</strong> 给我画一只可爱的猫。</p>
+      <img src="./public/cat_demo.svg" alt="猫咪绘图" width="240" />
+    </td>
+  </tr>
+</table>
+</div>
+
+## 工作原理
+
+本应用使用以下技术：
+
+-   **Next.js**：用于前端框架和路由
+-   **Vercel AI SDK**（`ai` + `@ai-sdk/*`）：用于流式AI响应和多提供商支持
+-   **react-drawio**：用于图表表示和操作
+
+图表以XML格式表示，可在draw.io中渲染。AI处理您的命令并相应地生成或修改此XML。
+
+## 多提供商支持
+
+-   AWS Bedrock（默认）
+-   OpenAI
+-   Anthropic
+-   Google AI
+-   Azure OpenAI
+-   Ollama
+-   OpenRouter
+-   DeepSeek
+
+除AWS Bedrock和OpenRouter外，所有提供商都支持自定义端点。
+
+📖 **[详细的提供商配置指南](./docs/ai-providers.md)** - 查看各提供商的设置说明。
+
+**模型要求**：此任务需要强大的模型能力，因为它涉及生成具有严格格式约束的长文本（draw.io XML）。推荐使用Claude Sonnet 4.5、GPT-4o、Gemini 2.0和DeepSeek V3/R1。
+
+注意：`claude-sonnet-4-5` 已在带有AWS标志的draw.io图表上进行训练，因此如果您想创建AWS架构图，这是最佳选择。
+
+## 快速开始
+
+### 使用Docker运行（推荐）
+
+如果您只想在本地运行，最好的方式是使用Docker。
+
+首先，如果您还没有安装Docker，请先安装：[获取Docker](https://docs.docker.com/get-docker/)
+
+然后运行：
+
+```bash
+docker run -d -p 3000:3000 \
+  -e AI_PROVIDER=openai \
+  -e AI_MODEL=gpt-4o \
+  -e OPENAI_API_KEY=your_api_key \
+  ghcr.io/dayuanjiang/next-ai-draw-io:latest
+```
+
+在浏览器中打开 [http://localhost:3000](http://localhost:3000)。
+
+请根据您首选的AI提供商配置替换环境变量。可用选项请参阅[多提供商支持](#多提供商支持)。
+
+### 安装
+
+1. 克隆仓库：
+
+```bash
+git clone https://github.com/DayuanJiang/next-ai-draw-io
+cd next-ai-draw-io
+```
+
+2. 安装依赖：
+
+```bash
+npm install
+# 或
+yarn install
+```
+
+3. 配置您的AI提供商：
+
+在根目录创建 `.env.local` 文件：
+
+```bash
+cp env.example .env.local
+```
+
+编辑 `.env.local` 并配置您选择的提供商：
+
+-   将 `AI_PROVIDER` 设置为您选择的提供商（bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek）
+-   将 `AI_MODEL` 设置为您要使用的特定模型
+-   添加您的提供商所需的API密钥
+-   `ACCESS_CODE_LIST` 访问密码，可选，可以使用逗号隔开多个密码。
+
+> 警告：如果不填写 `ACCESS_CODE_LIST`，则任何人都可以直接使用你部署后的网站，可能会导致你的 token 被急速消耗完毕，建议填写此选项。
+
+详细设置说明请参阅[提供商配置指南](./docs/ai-providers.md)。
+
+4. 运行开发服务器：
+
+```bash
+npm run dev
+```
+
+5. 在浏览器中打开 [http://localhost:3000](http://localhost:3000) 查看应用。
+
+## 部署
+
+部署Next.js应用最简单的方式是使用Next.js创建者提供的[Vercel平台](https://vercel.com/new)。
+
+查看[Next.js部署文档](https://nextjs.org/docs/app/building-your-application/deploying)了解更多详情。
+
+或者您可以通过此按钮部署：
+[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/clone?repository-url=https%3A%2F%2Fgithub.com%2FDayuanJiang%2Fnext-ai-draw-io)
+
+请确保在Vercel控制台中**设置环境变量**，就像您在本地 `.env.local` 文件中所做的那样。
+
+## 项目结构
+
+```
+app/                  # Next.js App Router
+  api/chat/           # 带AI工具的聊天API端点
+  page.tsx            # 带DrawIO嵌入的主页面
+components/           # React组件
+  chat-panel.tsx      # 带图表控制的聊天界面
+  chat-input.tsx      # 带文件上传的用户输入组件
+  history-dialog.tsx  # 图表版本历史查看器
+  ui/                 # UI组件（按钮、卡片等）
+contexts/             # React上下文提供者
+  diagram-context.tsx # 全局图表状态管理
+lib/                  # 工具函数和辅助程序
+  ai-providers.ts     # 多提供商AI配置
+  utils.ts            # XML处理和转换工具
+public/               # 静态资源包括示例图片
+```
+
+## 待办事项
+
+-   [x] 允许LLM修改XML而不是每次从头生成
+-   [x] 提高形状流式更新的流畅度
+-   [x] 添加多AI提供商支持（OpenAI, Anthropic, Google, Azure, Ollama）
+-   [x] 解决超过60秒的会话生成失败的bug
+-   [ ] 在UI上添加API配置
+
+## 支持与联系
+
+如果您觉得这个项目有用，请考虑[赞助](https://github.com/sponsors/DayuanJiang)来帮助我托管在线演示站点！
+
+如需支持或咨询，请在GitHub仓库上提交issue或联系维护者：
+
+-   邮箱：me[at]jiang.jp
+
+## Star历史
+
+[![Star History Chart](https://api.star-history.com/svg?repos=DayuanJiang/next-ai-draw-io&type=date&legend=top-left)](https://www.star-history.com/#DayuanJiang/next-ai-draw-io&type=date&legend=top-left)
+
+---

README_JA.md

@@ -0,0 +1,216 @@
+# Next AI Draw.io
+
+<div align="center">
+
+**AI搭載のダイアグラム作成ツール - チャット、描画、可視化**
+
+[English](./README.md) | [中文](./README_CN.md) | 日本語
+
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![Next.js](https://img.shields.io/badge/Next.js-15.x-black)](https://nextjs.org/)
+[![TypeScript](https://img.shields.io/badge/TypeScript-5.x-blue)](https://www.typescriptlang.org/)
+[![Sponsor](https://img.shields.io/badge/Sponsor-❤-ea4aaa)](https://github.com/sponsors/DayuanJiang)
+
+[🚀 ライブデモ](https://next-ai-drawio.jiang.jp/)
+
+</div>
+
+AI機能とdraw.ioダイアグラムを統合したNext.jsウェブアプリケーションです。自然言語コマンドとAI支援の可視化により、ダイアグラムを作成、修正、強化できます。
+
+https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
+
+## 機能
+
+-   **LLM搭載のダイアグラム作成**：大規模言語モデルを活用して、自然言語コマンドで直接draw.ioダイアグラムを作成・操作
+-   **画像ベースのダイアグラム複製**：既存のダイアグラムや画像をアップロードし、AIが自動的に複製・強化
+-   **ダイアグラム履歴**：すべての変更を追跡する包括的なバージョン管理。AI編集前のダイアグラムの以前のバージョンを表示・復元可能
+-   **インタラクティブなチャットインターフェース**：AIとリアルタイムでコミュニケーションしてダイアグラムを改善
+-   **AWSアーキテクチャダイアグラムサポート**：AWSアーキテクチャダイアグラムの生成を専門的にサポート
+-   **アニメーションコネクタ**：より良い可視化のためにダイアグラム要素間に動的でアニメーション化されたコネクタを作成
+
+## **例**
+
+以下はいくつかのプロンプト例と生成されたダイアグラムです：
+
+<div align="center">
+<table width="100%">
+  <tr>
+    <td colspan="2" valign="top" align="center">
+      <strong>アニメーションTransformerコネクタ</strong><br />
+      <p><strong>プロンプト：</strong> **アニメーションコネクタ**付きのTransformerアーキテクチャ図を作成してください。</p>
+      <img src="./public/animated_connectors.svg" alt="アニメーションコネクタ付きTransformerアーキテクチャ" width="480" />
+    </td>
+  </tr>
+  <tr>
+    <td width="50%" valign="top">
+      <strong>GCPアーキテクチャ図</strong><br />
+      <p><strong>プロンプト：</strong> **GCPアイコン**を使用してGCPアーキテクチャ図を生成してください。この図では、ユーザーがインスタンス上でホストされているフロントエンドに接続します。</p>
+      <img src="./public/gcp_demo.svg" alt="GCPアーキテクチャ図" width="480" />
+    </td>
+    <td width="50%" valign="top">
+      <strong>AWSアーキテクチャ図</strong><br />
+      <p><strong>プロンプト：</strong> **AWSアイコン**を使用してAWSアーキテクチャ図を生成してください。この図では、ユーザーがインスタンス上でホストされているフロントエンドに接続します。</p>
+      <img src="./public/aws_demo.svg" alt="AWSアーキテクチャ図" width="480" />
+    </td>
+  </tr>
+  <tr>
+    <td width="50%" valign="top">
+      <strong>Azureアーキテクチャ図</strong><br />
+      <p><strong>プロンプト：</strong> **Azureアイコン**を使用してAzureアーキテクチャ図を生成してください。この図では、ユーザーがインスタンス上でホストされているフロントエンドに接続します。</p>
+      <img src="./public/azure_demo.svg" alt="Azureアーキテクチャ図" width="480" />
+    </td>
+    <td width="50%" valign="top">
+      <strong>猫のスケッチ</strong><br />
+      <p><strong>プロンプト：</strong> かわいい猫を描いてください。</p>
+      <img src="./public/cat_demo.svg" alt="猫の絵" width="240" />
+    </td>
+  </tr>
+</table>
+</div>
+
+## 仕組み
+
+本アプリケーションは以下の技術を使用しています：
+
+-   **Next.js**：フロントエンドフレームワークとルーティング
+-   **Vercel AI SDK**（`ai` + `@ai-sdk/*`）：ストリーミングAIレスポンスとマルチプロバイダーサポート
+-   **react-drawio**：ダイアグラムの表現と操作
+
+ダイアグラムはdraw.ioでレンダリングできるXMLとして表現されます。AIがコマンドを処理し、それに応じてこのXMLを生成または変更します。
+
+## マルチプロバイダーサポート
+
+-   AWS Bedrock（デフォルト）
+-   OpenAI
+-   Anthropic
+-   Google AI
+-   Azure OpenAI
+-   Ollama
+-   OpenRouter
+-   DeepSeek
+
+AWS BedrockとOpenRouter以外のすべてのプロバイダーはカスタムエンドポイントをサポートしています。
+
+📖 **[詳細なプロバイダー設定ガイド](./docs/ai-providers.md)** - 各プロバイダーの設定手順をご覧ください。
+
+**モデル要件**：このタスクは厳密なフォーマット制約（draw.io XML）を持つ長文テキスト生成を伴うため、強力なモデル機能が必要です。Claude Sonnet 4.5、GPT-4o、Gemini 2.0、DeepSeek V3/R1を推奨します。
+
+注：`claude-sonnet-4-5`はAWSロゴ付きのdraw.ioダイアグラムで学習されているため、AWSアーキテクチャダイアグラムを作成したい場合は最適な選択です。
+
+## はじめに
+
+### Dockerで実行（推奨）
+
+ローカルで実行したいだけなら、Dockerを使用するのが最も簡単です。
+
+まず、Dockerをインストールしていない場合はインストールしてください：[Dockerを入手](https://docs.docker.com/get-docker/)
+
+次に実行：
+
+```bash
+docker run -d -p 3000:3000 \
+  -e AI_PROVIDER=openai \
+  -e AI_MODEL=gpt-4o \
+  -e OPENAI_API_KEY=your_api_key \
+  ghcr.io/dayuanjiang/next-ai-draw-io:latest
+```
+
+ブラウザで [http://localhost:3000](http://localhost:3000) を開いてください。
+
+環境変数はお好みのAIプロバイダー設定に置き換えてください。利用可能なオプションについては[マルチプロバイダーサポート](#マルチプロバイダーサポート)を参照してください。
+
+### インストール
+
+1. リポジトリをクローン：
+
+```bash
+git clone https://github.com/DayuanJiang/next-ai-draw-io
+cd next-ai-draw-io
+```
+
+2. 依存関係をインストール：
+
+```bash
+npm install
+# または
+yarn install
+```
+
+3. AIプロバイダーを設定：
+
+ルートディレクトリに`.env.local`ファイルを作成：
+
+```bash
+cp env.example .env.local
+```
+
+`.env.local`を編集して選択したプロバイダーを設定：
+
+-   `AI_PROVIDER`を選択したプロバイダーに設定（bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek）
+-   `AI_MODEL`を使用する特定のモデルに設定
+-   プロバイダーに必要なAPIキーを追加
+-   `ACCESS_CODE_LIST` アクセスパスワード（オプション）。カンマ区切りで複数のパスワードを指定できます。
+
+> 警告：`ACCESS_CODE_LIST`を設定しない場合、誰でもデプロイされたサイトに直接アクセスできるため、トークンが急速に消費される可能性があります。このオプションを設定することをお勧めします。
+
+詳細な設定手順については[プロバイダー設定ガイド](./docs/ai-providers.md)を参照してください。
+
+4. 開発サーバーを起動：
+
+```bash
+npm run dev
+```
+
+5. ブラウザで[http://localhost:3000](http://localhost:3000)を開いてアプリケーションを確認。
+
+## デプロイ
+
+Next.jsアプリをデプロイする最も簡単な方法は、Next.jsの作成者による[Vercelプラットフォーム](https://vercel.com/new)を使用することです。
+
+詳細は[Next.jsデプロイメントドキュメント](https://nextjs.org/docs/app/building-your-application/deploying)をご覧ください。
+
+または、このボタンでデプロイできます：
+[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/clone?repository-url=https%3A%2F%2Fgithub.com%2FDayuanJiang%2Fnext-ai-draw-io)
+
+ローカルの`.env.local`ファイルと同様に、Vercelダッシュボードで**環境変数を設定**してください。
+
+## プロジェクト構造
+
+```
+app/                  # Next.js App Router
+  api/chat/           # AIツール付きチャットAPIエンドポイント
+  page.tsx            # DrawIO埋め込み付きメインページ
+components/           # Reactコンポーネント
+  chat-panel.tsx      # ダイアグラム制御付きチャットインターフェース
+  chat-input.tsx      # ファイルアップロード付きユーザー入力コンポーネント
+  history-dialog.tsx  # ダイアグラムバージョン履歴ビューア
+  ui/                 # UIコンポーネント（ボタン、カードなど）
+contexts/             # Reactコンテキストプロバイダー
+  diagram-context.tsx # グローバルダイアグラム状態管理
+lib/                  # ユーティリティ関数とヘルパー
+  ai-providers.ts     # マルチプロバイダーAI設定
+  utils.ts            # XML処理と変換ユーティリティ
+public/               # サンプル画像を含む静的アセット
+```
+
+## TODO
+
+-   [x] LLMが毎回ゼロから生成する代わりにXMLを修正できるようにする
+-   [x] シェイプストリーミング更新の滑らかさを改善
+-   [x] 複数のAIプロバイダーサポートを追加（OpenAI, Anthropic, Google, Azure, Ollama）
+-   [x] 60秒以上のセッションで生成が失敗するバグを解決
+-   [ ] UIにAPI設定を追加
+
+## サポート＆お問い合わせ
+
+このプロジェクトが役に立ったら、ライブデモサイトのホスティングを支援するために[スポンサー](https://github.com/sponsors/DayuanJiang)をご検討ください！
+
+サポートやお問い合わせについては、GitHubリポジトリでissueを開くか、メンテナーにご連絡ください：
+
+-   メール：me[at]jiang.jp
+
+## スター履歴
+
+[![Star History Chart](https://api.star-history.com/svg?repos=DayuanJiang/next-ai-draw-io&type=date&legend=top-left)](https://www.star-history.com/#DayuanJiang/next-ai-draw-io&type=date&legend=top-left)
+
+---

amplify.yml

@@ -0,0 +1,22 @@
+version: 1
+frontend:
+  phases:
+    preBuild:
+      commands:
+        - npm ci --cache .npm --prefer-offline
+    build:
+      commands:
+        # Write env vars to .env.production for Next.js SSR runtime
+        - env | grep -e AI_MODEL >> .env.production
+        - env | grep -e AI_PROVIDER >> .env.production
+        - env | grep -e OPENAI_API_KEY >> .env.production
+        - env | grep -e NEXT_PUBLIC_ >> .env.production
+        - npm run build
+  artifacts:
+    baseDirectory: .next
+    files:
+      - '**/*'
+  cache:
+    paths:
+      - .next/cache/**/*
+      - .npm/**/*

app/about/cn/page.tsx

@@ -0,0 +1,334 @@
+import type { Metadata } from "next"
+import Image from "next/image"
+import Link from "next/link"
+import { FaGithub } from "react-icons/fa"
+
+export const metadata: Metadata = {
+    title: "关于 - Next AI Draw.io",
+    description:
+        "AI驱动的图表创建工具 - 对话、绘制、可视化。使用自然语言创建AWS、GCP和Azure架构图。",
+    keywords: ["AI图表", "draw.io", "AWS架构", "GCP图表", "Azure图表", "LLM"],
+}
+
+export default function AboutCN() {
+    return (
+        <div className="min-h-screen bg-gray-50">
+            {/* Navigation */}
+            <header className="bg-white border-b border-gray-200">
+                <div className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-4">
+                    <div className="flex items-center justify-between">
+                        <Link
+                            href="/"
+                            className="text-xl font-bold text-gray-900 hover:text-gray-700"
+                        >
+                            Next AI Draw.io
+                        </Link>
+                        <nav className="flex items-center gap-6 text-sm">
+                            <Link
+                                href="/"
+                                className="text-gray-600 hover:text-gray-900 transition-colors"
+                            >
+                                编辑器
+                            </Link>
+                            <Link
+                                href="/about/cn"
+                                className="text-blue-600 font-semibold"
+                            >
+                                关于
+                            </Link>
+                            <a
+                                href="https://github.com/DayuanJiang/next-ai-draw-io"
+                                target="_blank"
+                                rel="noopener noreferrer"
+                                className="text-gray-600 hover:text-gray-900 transition-colors"
+                                aria-label="在GitHub上查看"
+                            >
+                                <FaGithub className="w-5 h-5" />
+                            </a>
+                        </nav>
+                    </div>
+                </div>
+            </header>
+
+            {/* Main Content */}
+            <main className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-12">
+                <article className="prose prose-lg max-w-none">
+                    {/* Title */}
+                    <div className="text-center mb-8">
+                        <h1 className="text-4xl font-bold text-gray-900 mb-2">
+                            Next AI Draw.io
+                        </h1>
+                        <p className="text-xl text-gray-600 font-medium">
+                            AI驱动的图表创建工具 - 对话、绘制、可视化
+                        </p>
+                        <div className="flex justify-center gap-4 mt-4 text-sm">
+                            <Link
+                                href="/about"
+                                className="text-gray-600 hover:text-blue-600"
+                            >
+                                English
+                            </Link>
+                            <span className="text-gray-400">|</span>
+                            <Link
+                                href="/about/cn"
+                                className="text-blue-600 font-semibold"
+                            >
+                                中文
+                            </Link>
+                            <span className="text-gray-400">|</span>
+                            <Link
+                                href="/about/ja"
+                                className="text-gray-600 hover:text-blue-600"
+                            >
+                                日本語
+                            </Link>
+                        </div>
+                    </div>
+
+                    <div className="bg-amber-50 border border-amber-200 rounded-lg p-4 mb-6">
+                        <p className="text-amber-800">
+                            本应用设计运行于 Claude Opus 4.5
+                            以获得最佳性能。但由于流量超出预期，运行顶级模型的成本变得难以承受。为避免服务中断并控制成本，我已将后端切换至
+                            Claude Haiku 4.5。
+                        </p>
+                    </div>
+
+                    <p className="text-gray-700">
+                        一个集成了AI功能的Next.js网页应用，与draw.io图表无缝结合。通过自然语言命令和AI辅助可视化来创建、修改和增强图表。
+                    </p>
+
+                    {/* Features */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        功能特性
+                    </h2>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-2">
+                        <li>
+                            <strong>LLM驱动的图表创建</strong>
+                            ：利用大语言模型通过自然语言命令直接创建和操作draw.io图表
+                        </li>
+                        <li>
+                            <strong>基于图像的图表复制</strong>
+                            ：上传现有图表或图像，让AI自动复制和增强
+                        </li>
+                        <li>
+                            <strong>图表历史记录</strong>
+                            ：全面的版本控制，跟踪所有更改，允许您查看和恢复AI编辑前的图表版本
+                        </li>
+                        <li>
+                            <strong>交互式聊天界面</strong>
+                            ：与AI实时对话来完善您的图表
+                        </li>
+                        <li>
+                            <strong>AWS架构图支持</strong>
+                            ：专门支持生成AWS架构图
+                        </li>
+                        <li>
+                            <strong>动画连接器</strong>
+                            ：在图表元素之间创建动态动画连接器，实现更好的可视化效果
+                        </li>
+                    </ul>
+
+                    {/* Examples */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        示例
+                    </h2>
+                    <p className="text-gray-700 mb-6">
+                        以下是一些示例提示词及其生成的图表：
+                    </p>
+
+                    <div className="space-y-8">
+                        {/* Animated Transformer */}
+                        <div className="text-center">
+                            <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                动画Transformer连接器
+                            </h3>
+                            <p className="text-gray-600 mb-4">
+                                <strong>提示词：</strong> 给我一个带有
+                                <strong>动画连接器</strong>的Transformer架构图。
+                            </p>
+                            <Image
+                                src="/animated_connectors.svg"
+                                alt="带动画连接器的Transformer架构"
+                                width={480}
+                                height={360}
+                                className="mx-auto"
+                            />
+                        </div>
+
+                        {/* Cloud Architecture Grid */}
+                        <div className="grid md:grid-cols-2 gap-6">
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    GCP架构图
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>提示词：</strong> 使用
+                                    <strong>GCP图标</strong>
+                                    生成一个GCP架构图。用户连接到托管在实例上的前端。
+                                </p>
+                                <Image
+                                    src="/gcp_demo.svg"
+                                    alt="GCP架构图"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
+                            </div>
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    AWS架构图
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>提示词：</strong> 使用
+                                    <strong>AWS图标</strong>
+                                    生成一个AWS架构图。用户连接到托管在实例上的前端。
+                                </p>
+                                <Image
+                                    src="/aws_demo.svg"
+                                    alt="AWS架构图"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
+                            </div>
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    Azure架构图
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>提示词：</strong> 使用
+                                    <strong>Azure图标</strong>
+                                    生成一个Azure架构图。用户连接到托管在实例上的前端。
+                                </p>
+                                <Image
+                                    src="/azure_demo.svg"
+                                    alt="Azure架构图"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
+                            </div>
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    猫咪素描
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>提示词：</strong>{" "}
+                                    给我画一只可爱的猫。
+                                </p>
+                                <Image
+                                    src="/cat_demo.svg"
+                                    alt="猫咪绘图"
+                                    width={240}
+                                    height={240}
+                                    className="mx-auto"
+                                />
+                            </div>
+                        </div>
+                    </div>
+
+                    {/* How It Works */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        工作原理
+                    </h2>
+                    <p className="text-gray-700 mb-4">本应用使用以下技术：</p>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-2">
+                        <li>
+                            <strong>Next.js</strong>：用于前端框架和路由
+                        </li>
+                        <li>
+                            <strong>Vercel AI SDK</strong>（<code>ai</code> +{" "}
+                            <code>@ai-sdk/*</code>
+                            ）：用于流式AI响应和多提供商支持
+                        </li>
+                        <li>
+                            <strong>react-drawio</strong>：用于图表表示和操作
+                        </li>
+                    </ul>
+                    <p className="text-gray-700 mt-4">
+                        图表以XML格式表示，可在draw.io中渲染。AI处理您的命令并相应地生成或修改此XML。
+                    </p>
+
+                    {/* Multi-Provider Support */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        多提供商支持
+                    </h2>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-1">
+                        <li>AWS Bedrock（默认）</li>
+                        <li>
+                            OpenAI / OpenAI兼容API（通过{" "}
+                            <code>OPENAI_BASE_URL</code>）
+                        </li>
+                        <li>Anthropic</li>
+                        <li>Google AI</li>
+                        <li>Azure OpenAI</li>
+                        <li>Ollama</li>
+                        <li>OpenRouter</li>
+                        <li>DeepSeek</li>
+                    </ul>
+                    <p className="text-gray-700 mt-4">
+                        注意：<code>claude-sonnet-4-5</code>{" "}
+                        已在带有AWS标志的draw.io图表上进行训练，因此如果您想创建AWS架构图，这是最佳选择。
+                    </p>
+
+                    {/* Support */}
+                    <div className="flex items-center gap-4 mt-10 mb-4">
+                        <h2 className="text-2xl font-semibold text-gray-900">
+                            支持与联系
+                        </h2>
+                        <iframe
+                            src="https://github.com/sponsors/DayuanJiang/button"
+                            title="Sponsor DayuanJiang"
+                            height="32"
+                            width="114"
+                            style={{ border: 0, borderRadius: 6 }}
+                        />
+                    </div>
+                    <p className="text-gray-700">
+                        如果您觉得这个项目有用，请考虑{" "}
+                        <a
+                            href="https://github.com/sponsors/DayuanJiang"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="text-blue-600 hover:underline"
+                        >
+                            赞助
+                        </a>{" "}
+                        来帮助托管在线演示站点！
+                    </p>
+                    <p className="text-gray-700 mt-2">
+                        如需支持或咨询，请在{" "}
+                        <a
+                            href="https://github.com/DayuanJiang/next-ai-draw-io"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="text-blue-600 hover:underline"
+                        >
+                            GitHub仓库
+                        </a>{" "}
+                        上提交issue或联系：me[at]jiang.jp
+                    </p>
+
+                    {/* CTA */}
+                    <div className="mt-12 text-center">
+                        <Link
+                            href="/"
+                            className="inline-block bg-blue-600 text-white px-8 py-3 rounded-lg font-semibold hover:bg-blue-700 transition-colors"
+                        >
+                            打开编辑器
+                        </Link>
+                    </div>
+                </article>
+            </main>
+
+            {/* Footer */}
+            <footer className="bg-white border-t border-gray-200 mt-16">
+                <div className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-6">
+                    <p className="text-center text-gray-600 text-sm">
+                        Next AI Draw.io - 开源AI驱动的图表生成器
+                    </p>
+                </div>
+            </footer>
+        </div>
+    )
+}

app/about/ja/page.tsx

@@ -0,0 +1,353 @@
+import type { Metadata } from "next"
+import Image from "next/image"
+import Link from "next/link"
+import { FaGithub } from "react-icons/fa"
+
+export const metadata: Metadata = {
+    title: "概要 - Next AI Draw.io",
+    description:
+        "AI搭載のダイアグラム作成ツール - チャット、描画、可視化。自然言語でAWS、GCP、Azureアーキテクチャ図を作成。",
+    keywords: [
+        "AIダイアグラム",
+        "draw.io",
+        "AWSアーキテクチャ",
+        "GCPダイアグラム",
+        "Azureダイアグラム",
+        "LLM",
+    ],
+}
+
+export default function AboutJA() {
+    return (
+        <div className="min-h-screen bg-gray-50">
+            {/* Navigation */}
+            <header className="bg-white border-b border-gray-200">
+                <div className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-4">
+                    <div className="flex items-center justify-between">
+                        <Link
+                            href="/"
+                            className="text-xl font-bold text-gray-900 hover:text-gray-700"
+                        >
+                            Next AI Draw.io
+                        </Link>
+                        <nav className="flex items-center gap-6 text-sm">
+                            <Link
+                                href="/"
+                                className="text-gray-600 hover:text-gray-900 transition-colors"
+                            >
+                                エディタ
+                            </Link>
+                            <Link
+                                href="/about/ja"
+                                className="text-blue-600 font-semibold"
+                            >
+                                概要
+                            </Link>
+                            <a
+                                href="https://github.com/DayuanJiang/next-ai-draw-io"
+                                target="_blank"
+                                rel="noopener noreferrer"
+                                className="text-gray-600 hover:text-gray-900 transition-colors"
+                                aria-label="GitHubで見る"
+                            >
+                                <FaGithub className="w-5 h-5" />
+                            </a>
+                        </nav>
+                    </div>
+                </div>
+            </header>
+
+            {/* Main Content */}
+            <main className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-12">
+                <article className="prose prose-lg max-w-none">
+                    {/* Title */}
+                    <div className="text-center mb-8">
+                        <h1 className="text-4xl font-bold text-gray-900 mb-2">
+                            Next AI Draw.io
+                        </h1>
+                        <p className="text-xl text-gray-600 font-medium">
+                            AI搭載のダイアグラム作成ツール -
+                            チャット、描画、可視化
+                        </p>
+                        <div className="flex justify-center gap-4 mt-4 text-sm">
+                            <Link
+                                href="/about"
+                                className="text-gray-600 hover:text-blue-600"
+                            >
+                                English
+                            </Link>
+                            <span className="text-gray-400">|</span>
+                            <Link
+                                href="/about/cn"
+                                className="text-gray-600 hover:text-blue-600"
+                            >
+                                中文
+                            </Link>
+                            <span className="text-gray-400">|</span>
+                            <Link
+                                href="/about/ja"
+                                className="text-blue-600 font-semibold"
+                            >
+                                日本語
+                            </Link>
+                        </div>
+                    </div>
+
+                    <div className="bg-amber-50 border border-amber-200 rounded-lg p-4 mb-6">
+                        <p className="text-amber-800">
+                            本アプリは最高のパフォーマンスを発揮するため、Claude
+                            Opus 4.5
+                            で動作するよう設計されています。しかし、予想以上のトラフィックにより、最上位モデルの運用コストが負担となっています。サービスの中断を避け、コストを管理するため、バックエンドを
+                            Claude Haiku 4.5 に切り替えました。
+                        </p>
+                    </div>
+
+                    <p className="text-gray-700">
+                        AI機能とdraw.ioダイアグラムを統合したNext.jsウェブアプリケーションです。自然言語コマンドとAI支援の可視化により、ダイアグラムを作成、修正、強化できます。
+                    </p>
+
+                    {/* Features */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        機能
+                    </h2>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-2">
+                        <li>
+                            <strong>LLM搭載のダイアグラム作成</strong>
+                            ：大規模言語モデルを活用して、自然言語コマンドで直接draw.ioダイアグラムを作成・操作
+                        </li>
+                        <li>
+                            <strong>画像ベースのダイアグラム複製</strong>
+                            ：既存のダイアグラムや画像をアップロードし、AIが自動的に複製・強化
+                        </li>
+                        <li>
+                            <strong>ダイアグラム履歴</strong>
+                            ：すべての変更を追跡する包括的なバージョン管理。AI編集前のダイアグラムの以前のバージョンを表示・復元可能
+                        </li>
+                        <li>
+                            <strong>
+                                インタラクティブなチャットインターフェース
+                            </strong>
+                            ：AIとリアルタイムでコミュニケーションしてダイアグラムを改善
+                        </li>
+                        <li>
+                            <strong>
+                                AWSアーキテクチャダイアグラムサポート
+                            </strong>
+                            ：AWSアーキテクチャダイアグラムの生成を専門的にサポート
+                        </li>
+                        <li>
+                            <strong>アニメーションコネクタ</strong>
+                            ：より良い可視化のためにダイアグラム要素間に動的でアニメーション化されたコネクタを作成
+                        </li>
+                    </ul>
+
+                    {/* Examples */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        例
+                    </h2>
+                    <p className="text-gray-700 mb-6">
+                        以下はいくつかのプロンプト例と生成されたダイアグラムです：
+                    </p>
+
+                    <div className="space-y-8">
+                        {/* Animated Transformer */}
+                        <div className="text-center">
+                            <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                アニメーションTransformerコネクタ
+                            </h3>
+                            <p className="text-gray-600 mb-4">
+                                <strong>プロンプト：</strong>{" "}
+                                <strong>アニメーションコネクタ</strong>
+                                付きのTransformerアーキテクチャ図を作成してください。
+                            </p>
+                            <Image
+                                src="/animated_connectors.svg"
+                                alt="アニメーションコネクタ付きTransformerアーキテクチャ"
+                                width={480}
+                                height={360}
+                                className="mx-auto"
+                            />
+                        </div>
+
+                        {/* Cloud Architecture Grid */}
+                        <div className="grid md:grid-cols-2 gap-6">
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    GCPアーキテクチャ図
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>プロンプト：</strong>{" "}
+                                    <strong>GCPアイコン</strong>
+                                    を使用してGCPアーキテクチャ図を生成してください。ユーザーがインスタンス上でホストされているフロントエンドに接続します。
+                                </p>
+                                <Image
+                                    src="/gcp_demo.svg"
+                                    alt="GCPアーキテクチャ図"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
+                            </div>
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    AWSアーキテクチャ図
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>プロンプト：</strong>{" "}
+                                    <strong>AWSアイコン</strong>
+                                    を使用してAWSアーキテクチャ図を生成してください。ユーザーがインスタンス上でホストされているフロントエンドに接続します。
+                                </p>
+                                <Image
+                                    src="/aws_demo.svg"
+                                    alt="AWSアーキテクチャ図"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
+                            </div>
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    Azureアーキテクチャ図
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>プロンプト：</strong>{" "}
+                                    <strong>Azureアイコン</strong>
+                                    を使用してAzureアーキテクチャ図を生成してください。ユーザーがインスタンス上でホストされているフロントエンドに接続します。
+                                </p>
+                                <Image
+                                    src="/azure_demo.svg"
+                                    alt="Azureアーキテクチャ図"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
+                            </div>
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    猫のスケッチ
+                                </h3>
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>プロンプト：</strong>{" "}
+                                    かわいい猫を描いてください。
+                                </p>
+                                <Image
+                                    src="/cat_demo.svg"
+                                    alt="猫の絵"
+                                    width={240}
+                                    height={240}
+                                    className="mx-auto"
+                                />
+                            </div>
+                        </div>
+                    </div>
+
+                    {/* How It Works */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        仕組み
+                    </h2>
+                    <p className="text-gray-700 mb-4">
+                        本アプリケーションは以下の技術を使用しています：
+                    </p>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-2">
+                        <li>
+                            <strong>Next.js</strong>
+                            ：フロントエンドフレームワークとルーティング
+                        </li>
+                        <li>
+                            <strong>Vercel AI SDK</strong>（<code>ai</code> +{" "}
+                            <code>@ai-sdk/*</code>
+                            ）：ストリーミングAIレスポンスとマルチプロバイダーサポート
+                        </li>
+                        <li>
+                            <strong>react-drawio</strong>
+                            ：ダイアグラムの表現と操作
+                        </li>
+                    </ul>
+                    <p className="text-gray-700 mt-4">
+                        ダイアグラムはdraw.ioでレンダリングできるXMLとして表現されます。AIがコマンドを処理し、それに応じてこのXMLを生成または変更します。
+                    </p>
+
+                    {/* Multi-Provider Support */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        マルチプロバイダーサポート
+                    </h2>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-1">
+                        <li>AWS Bedrock（デフォルト）</li>
+                        <li>
+                            OpenAI / OpenAI互換API（<code>OPENAI_BASE_URL</code>
+                            経由）
+                        </li>
+                        <li>Anthropic</li>
+                        <li>Google AI</li>
+                        <li>Azure OpenAI</li>
+                        <li>Ollama</li>
+                        <li>OpenRouter</li>
+                        <li>DeepSeek</li>
+                    </ul>
+                    <p className="text-gray-700 mt-4">
+                        注：<code>claude-sonnet-4-5</code>
+                        はAWSロゴ付きのdraw.ioダイアグラムで学習されているため、AWSアーキテクチャダイアグラムを作成したい場合は最適な選択です。
+                    </p>
+
+                    {/* Support */}
+                    <div className="flex items-center gap-4 mt-10 mb-4">
+                        <h2 className="text-2xl font-semibold text-gray-900">
+                            サポート＆お問い合わせ
+                        </h2>
+                        <iframe
+                            src="https://github.com/sponsors/DayuanJiang/button"
+                            title="Sponsor DayuanJiang"
+                            height="32"
+                            width="114"
+                            style={{ border: 0, borderRadius: 6 }}
+                        />
+                    </div>
+                    <p className="text-gray-700">
+                        このプロジェクトが役に立ったら、ライブデモサイトのホスティングを支援するために{" "}
+                        <a
+                            href="https://github.com/sponsors/DayuanJiang"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="text-blue-600 hover:underline"
+                        >
+                            スポンサー
+                        </a>{" "}
+                        をご検討ください！
+                    </p>
+                    <p className="text-gray-700 mt-2">
+                        サポートやお問い合わせについては、{" "}
+                        <a
+                            href="https://github.com/DayuanJiang/next-ai-draw-io"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="text-blue-600 hover:underline"
+                        >
+                            GitHubリポジトリ
+                        </a>{" "}
+                        でissueを開くか、ご連絡ください：me[at]jiang.jp
+                    </p>
+
+                    {/* CTA */}
+                    <div className="mt-12 text-center">
+                        <Link
+                            href="/"
+                            className="inline-block bg-blue-600 text-white px-8 py-3 rounded-lg font-semibold hover:bg-blue-700 transition-colors"
+                        >
+                            エディタを開く
+                        </Link>
+                    </div>
+                </article>
+            </main>
+
+            {/* Footer */}
+            <footer className="bg-white border-t border-gray-200 mt-16">
+                <div className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-6">
+                    <p className="text-center text-gray-600 text-sm">
+                        Next AI Draw.io -
+                        オープンソースAI搭載ダイアグラムジェネレーター
+                    </p>
+                </div>
+            </footer>
+        </div>
+    )
+}

app/about/page.tsx

@@ -1,28 +1,46 @@
-import type { Metadata } from "next";
-import Link from "next/link";
-import { FaGithub } from "react-icons/fa";
+import type { Metadata } from "next"
+import Image from "next/image"
+import Link from "next/link"
+import { FaGithub } from "react-icons/fa"
 
 export const metadata: Metadata = {
-    title: "About - AI-Powered Diagram Generator | Next AI Draw.io",
-    description: "Learn about Next AI Draw.io, a free AI-powered diagram creation tool. Create AWS architecture diagrams, flowcharts, and UML diagrams using Claude Sonnet and GPT-4. No login required.",
-    keywords: ["about AI diagram generator", "diagram tool features", "how to create diagrams", "AI drawing tool capabilities", "draw.io integration"],
-};
+    title: "About - Next AI Draw.io",
+    description:
+        "AI-Powered Diagram Creation Tool - Chat, Draw, Visualize. Create AWS, GCP, and Azure architecture diagrams with natural language.",
+    keywords: [
+        "AI diagram",
+        "draw.io",
+        "AWS architecture",
+        "GCP diagram",
+        "Azure diagram",
+        "LLM",
+    ],
+}
 
 export default function About() {
     return (
         <div className="min-h-screen bg-gray-50">
             {/* Navigation */}
             <header className="bg-white border-b border-gray-200">
-                <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-4">
+                <div className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-4">
                     <div className="flex items-center justify-between">
-                        <Link href="/" className="text-xl font-bold text-gray-900 hover:text-gray-700">
+                        <Link
+                            href="/"
+                            className="text-xl font-bold text-gray-900 hover:text-gray-700"
+                        >
                             Next AI Draw.io
                         </Link>
                         <nav className="flex items-center gap-6 text-sm">
-                            <Link href="/" className="text-gray-600 hover:text-gray-900 transition-colors">
+                            <Link
+                                href="/"
+                                className="text-gray-600 hover:text-gray-900 transition-colors"
+                            >
                                 Editor
                             </Link>
-                            <Link href="/about" className="text-blue-600 font-semibold">
+                            <Link
+                                href="/about"
+                                className="text-blue-600 font-semibold"
+                            >
                                 About
                             </Link>
                             <a
@@ -40,297 +58,313 @@ export default function About() {
             </header>
 
             {/* Main Content */}
-            <main className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-12">
-                <article>
-                    {/* Hero Section */}
-                    <header className="mb-12">
-                        <h1 className="text-4xl font-bold text-gray-900 mb-4">
-                            AI-Powered Diagram Generator | Create Professional Diagrams Instantly
+            <main className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-12">
+                <article className="prose prose-lg max-w-none">
+                    {/* Title */}
+                    <div className="text-center mb-8">
+                        <h1 className="text-4xl font-bold text-gray-900 mb-2">
+                            Next AI Draw.io
                         </h1>
-                        <p className="text-xl text-gray-600">
-                            Free, open-source diagram creation tool powered by AI. No login required, no installation needed.
+                        <p className="text-xl text-gray-600 font-medium">
+                            AI-Powered Diagram Creation Tool - Chat, Draw,
+                            Visualize
                         </p>
-                    </header>
+                        <div className="flex justify-center gap-4 mt-4 text-sm">
+                            <Link
+                                href="/about"
+                                className="text-blue-600 font-semibold"
+                            >
+                                English
+                            </Link>
+                            <span className="text-gray-400">|</span>
+                            <Link
+                                href="/about/cn"
+                                className="text-gray-600 hover:text-blue-600"
+                            >
+                                中文
+                            </Link>
+                            <span className="text-gray-400">|</span>
+                            <Link
+                                href="/about/ja"
+                                className="text-gray-600 hover:text-blue-600"
+                            >
+                                日本語
+                            </Link>
+                        </div>
+                    </div>
 
-                    {/* Introduction */}
-                    <section className="mb-12">
-                        <h2 className="text-2xl font-semibold text-gray-900 mb-4">What is Next AI Draw.io?</h2>
-                        <div className="prose prose-lg max-w-none text-gray-700">
-                            <p className="mb-4">
-                                <strong>Next AI Draw.io</strong> is a free, AI-powered diagram creation tool that integrates seamlessly with draw.io.
-                                Generate AWS architecture diagrams, flowcharts, UML diagrams, and technical documentation diagrams using natural language
-                                prompts. No login required, no installation needed—start creating professional diagrams instantly in your browser.
-                            </p>
-                            <p className="mb-4">
-                                Our intelligent diagram generator uses advanced AI models including <strong>Claude Sonnet</strong> and <strong>GPT-4</strong> to
-                                understand your requirements and automatically create properly structured diagrams with appropriate symbols, layouts, and connections.
-                                Simply describe what you need, upload reference images, or ask the AI to modify existing diagrams with our targeted XML editing feature.
-                            </p>
-                            <p>
-                                Whether you're a software architect designing system infrastructure, a developer documenting APIs, a business analyst creating
-                                process flows, or a student working on technical assignments, Next AI Draw.io makes diagram creation fast, accurate, and effortless.
+                    <div className="bg-amber-50 border border-amber-200 rounded-lg p-4 mb-6">
+                        <p className="text-amber-800">
+                            This app is designed to run on Claude Opus 4.5 for
+                            best performance. However, due to
+                            higher-than-expected traffic, running the top-tier
+                            model has become cost-prohibitive. To avoid service
+                            interruptions and manage costs, I have switched the
+                            backend to Claude Haiku 4.5.
                         </p>
                     </div>
-                    </section>
 
-                    {/* Key Features */}
-                    <section className="mb-12">
-                        <h2 className="text-2xl font-semibold text-gray-900 mb-6">Key Features</h2>
+                    <p className="text-gray-700">
+                        A Next.js web application that integrates AI
+                        capabilities with draw.io diagrams. Create, modify, and
+                        enhance diagrams through natural language commands and
+                        AI-assisted visualization.
+                    </p>
+
+                    {/* Features */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        Features
+                    </h2>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-2">
+                        <li>
+                            <strong>LLM-Powered Diagram Creation</strong>:
+                            Leverage Large Language Models to create and
+                            manipulate draw.io diagrams directly through natural
+                            language commands
+                        </li>
+                        <li>
+                            <strong>Image-Based Diagram Replication</strong>:
+                            Upload existing diagrams or images and have the AI
+                            replicate and enhance them automatically
+                        </li>
+                        <li>
+                            <strong>Diagram History</strong>: Comprehensive
+                            version control that tracks all changes, allowing
+                            you to view and restore previous versions of your
+                            diagrams before the AI editing
+                        </li>
+                        <li>
+                            <strong>Interactive Chat Interface</strong>:
+                            Communicate with AI to refine your diagrams in
+                            real-time
+                        </li>
+                        <li>
+                            <strong>AWS Architecture Diagram Support</strong>:
+                            Specialized support for generating AWS architecture
+                            diagrams
+                        </li>
+                        <li>
+                            <strong>Animated Connectors</strong>: Create dynamic
+                            and animated connectors between diagram elements for
+                            better visualization
+                        </li>
+                    </ul>
+
+                    {/* Examples */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        Examples
+                    </h2>
+                    <p className="text-gray-700 mb-6">
+                        Here are some example prompts and their generated
+                        diagrams:
+                    </p>
+
+                    <div className="space-y-8">
+                        {/* Animated Transformer */}
+                        <div className="text-center">
+                            <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                Animated Transformer Connectors
+                            </h3>
+                            <p className="text-gray-600 mb-4">
+                                <strong>Prompt:</strong> Give me an{" "}
+                                <strong>animated connector</strong> diagram of
+                                transformer&apos;s architecture.
+                            </p>
+                            <Image
+                                src="/animated_connectors.svg"
+                                alt="Transformer Architecture with Animated Connectors"
+                                width={480}
+                                height={360}
+                                className="mx-auto"
+                            />
+                        </div>
+
+                        {/* Cloud Architecture Grid */}
                         <div className="grid md:grid-cols-2 gap-6">
-                            <div className="bg-white p-6 rounded-lg border border-gray-200 shadow-sm">
-                                <h3 className="text-lg font-semibold text-gray-900 mb-3 flex items-center">
-                                    <span className="text-blue-600 mr-2">✓</span>
-                                    AI-Powered Diagram Creation
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    GCP Architecture Diagram
                                 </h3>
-                                <p className="text-gray-700">
-                                    Generate diagrams from natural language descriptions using Claude Sonnet or GPT-4.
-                                    Describe your diagram in plain English, and watch the AI create it with proper symbols,
-                                    layouts, and connections automatically.
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>Prompt:</strong> Generate a GCP
+                                    architecture diagram with{" "}
+                                    <strong>GCP icons</strong>. Users connect to
+                                    a frontend hosted on an instance.
                                 </p>
+                                <Image
+                                    src="/gcp_demo.svg"
+                                    alt="GCP Architecture Diagram"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
                             </div>
-
-                            <div className="bg-white p-6 rounded-lg border border-gray-200 shadow-sm">
-                                <h3 className="text-lg font-semibold text-gray-900 mb-3 flex items-center">
-                                    <span className="text-blue-600 mr-2">✓</span>
-                                    AWS Architecture Diagrams
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    AWS Architecture Diagram
                                 </h3>
-                                <p className="text-gray-700">
-                                    Create professional cloud infrastructure diagrams with AWS-style icons and layouts.
-                                    Perfect for designing EC2 instances, Lambda functions, S3 buckets, RDS databases, VPCs,
-                                    and complete AWS solution architectures.
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>Prompt:</strong> Generate an AWS
+                                    architecture diagram with{" "}
+                                    <strong>AWS icons</strong>. Users connect to
+                                    a frontend hosted on an instance.
                                 </p>
+                                <Image
+                                    src="/aws_demo.svg"
+                                    alt="AWS Architecture Diagram"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
                             </div>
-
-                            <div className="bg-white p-6 rounded-lg border border-gray-200 shadow-sm">
-                                <h3 className="text-lg font-semibold text-gray-900 mb-3 flex items-center">
-                                    <span className="text-blue-600 mr-2">✓</span>
-                                    Image-Based Diagram Replication
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    Azure Architecture Diagram
                                 </h3>
-                                <p className="text-gray-700">
-                                    Upload existing diagrams or sketches, and the AI will automatically recreate them in draw.io format.
-                                    Modify uploaded images by describing the changes you want—the AI handles the rest.
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>Prompt:</strong> Generate an Azure
+                                    architecture diagram with{" "}
+                                    <strong>Azure icons</strong>. Users connect
+                                    to a frontend hosted on an instance.
                                 </p>
+                                <Image
+                                    src="/azure_demo.svg"
+                                    alt="Azure Architecture Diagram"
+                                    width={400}
+                                    height={300}
+                                    className="mx-auto"
+                                />
                             </div>
-
-                            <div className="bg-white p-6 rounded-lg border border-gray-200 shadow-sm">
-                                <h3 className="text-lg font-semibold text-gray-900 mb-3 flex items-center">
-                                    <span className="text-blue-600 mr-2">✓</span>
-                                    Diagram History & Version Control
+                            <div className="text-center">
+                                <h3 className="text-lg font-semibold text-gray-900 mb-2">
+                                    Cat Sketch
                                 </h3>
-                                <p className="text-gray-700">
-                                    Access previous versions of your diagrams and restore any version from your session history.
-                                    Never lose work—every AI modification is saved and can be undone with a single click.
-                                </p>
-                            </div>
-
-                            <div className="bg-white p-6 rounded-lg border border-gray-200 shadow-sm">
-                                <h3 className="text-lg font-semibold text-gray-900 mb-3 flex items-center">
-                                    <span className="text-blue-600 mr-2">✓</span>
-                                    Targeted XML Editing
-                                </h3>
-                                <p className="text-gray-700">
-                                    Precise diagram modifications using intelligent XML manipulation. Unlike full diagram regeneration,
-                                    targeted edits preserve your existing layout while making specific changes, ensuring consistent
-                                    and predictable results.
-                                </p>
-                            </div>
-
-                            <div className="bg-white p-6 rounded-lg border border-gray-200 shadow-sm">
-                                <h3 className="text-lg font-semibold text-gray-900 mb-3 flex items-center">
-                                    <span className="text-blue-600 mr-2">✓</span>
-                                    Multi-Provider AI Support
-                                </h3>
-                                <p className="text-gray-700">
-                                    Choose between Claude Sonnet, GPT-4, and other leading AI models for optimal results.
-                                    Each model has unique strengths—select the one that best fits your diagram complexity and style.
+                                <p className="text-gray-600 text-sm mb-4">
+                                    <strong>Prompt:</strong> Draw a cute cat for
+                                    me.
                                 </p>
+                                <Image
+                                    src="/cat_demo.svg"
+                                    alt="Cat Drawing"
+                                    width={240}
+                                    height={240}
+                                    className="mx-auto"
+                                />
                             </div>
                         </div>
-                    </section>
-
-                    {/* Use Cases */}
-                    <section className="mb-12">
-                        <h2 className="text-2xl font-semibold text-gray-900 mb-6">Popular Use Cases</h2>
-                        <div className="grid md:grid-cols-3 gap-6">
-                            <div className="bg-blue-50 p-6 rounded-lg border border-blue-200">
-                                <h3 className="text-xl font-semibold text-gray-900 mb-3">AWS Cloud Architecture</h3>
-                                <p className="text-gray-700 mb-4">
-                                    Design scalable cloud infrastructure with EC2 instances, Lambda functions, S3 storage,
-                                    RDS databases, and VPC networking. Perfect for solution architects, cloud engineers,
-                                    and DevOps teams planning AWS deployments.
-                                </p>
-                                <p className="text-sm text-gray-600 italic">
-                                    Example: "Create an AWS diagram with an Application Load Balancer, two EC2 instances
-                                    in different availability zones, an RDS database, and an S3 bucket for static assets."
-                                </p>
                     </div>
 
-                            <div className="bg-green-50 p-6 rounded-lg border border-green-200">
-                                <h3 className="text-xl font-semibold text-gray-900 mb-3">Flowcharts & Process Diagrams</h3>
-                                <p className="text-gray-700 mb-4">
-                                    Create business process flows, decision trees, workflow diagrams, and algorithm flowcharts
-                                    for documentation, presentations, and process optimization. Ideal for business analysts,
-                                    project managers, and operations teams.
-                                </p>
-                                <p className="text-sm text-gray-600 italic">
-                                    Example: "Draw a flowchart for user authentication: check if user exists, verify password,
-                                    generate JWT token on success, show error message on failure."
-                                </p>
-                            </div>
-
-                            <div className="bg-purple-50 p-6 rounded-lg border border-purple-200">
-                                <h3 className="text-xl font-semibold text-gray-900 mb-3">System Design & UML Diagrams</h3>
-                                <p className="text-gray-700 mb-4">
-                                    Generate system architecture diagrams, class diagrams, sequence diagrams, and
-                                    entity-relationship diagrams for software projects. Essential for software engineers,
-                                    system designers, and technical documentation.
-                                </p>
-                                <p className="text-sm text-gray-600 italic">
-                                    Example: "Create a class diagram for an e-commerce system with User, Product, Order,
-                                    and Payment classes showing their relationships and key methods."
-                                </p>
-                            </div>
-                        </div>
-                    </section>
-
                     {/* How It Works */}
-                    <section className="mb-12 bg-white p-8 rounded-lg border border-gray-200">
-                        <h2 className="text-2xl font-semibold text-gray-900 mb-6">How to Use Next AI Draw.io</h2>
-                        <div className="space-y-6">
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 w-10 h-10 bg-blue-600 text-white rounded-full flex items-center justify-center font-bold mr-4">
-                                    1
-                                </div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Open the Editor</h3>
-                                    <p className="text-gray-700">
-                                        Navigate to the main page and you'll see the draw.io editor with an AI chat panel on the right.
-                                        No account creation or login required—start immediately.
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        How It Works
+                    </h2>
+                    <p className="text-gray-700 mb-4">
+                        The application uses the following technologies:
+                    </p>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-2">
+                        <li>
+                            <strong>Next.js</strong>: For the frontend framework
+                            and routing
+                        </li>
+                        <li>
+                            <strong>Vercel AI SDK</strong> (<code>ai</code> +{" "}
+                            <code>@ai-sdk/*</code>): For streaming AI responses
+                            and multi-provider support
+                        </li>
+                        <li>
+                            <strong>react-drawio</strong>: For diagram
+                            representation and manipulation
+                        </li>
+                    </ul>
+                    <p className="text-gray-700 mt-4">
+                        Diagrams are represented as XML that can be rendered in
+                        draw.io. The AI processes your commands and generates or
+                        modifies this XML accordingly.
                     </p>
-                                </div>
-                            </div>
 
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 w-10 h-10 bg-blue-600 text-white rounded-full flex items-center justify-center font-bold mr-4">
-                                    2
-                                </div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Describe Your Diagram</h3>
-                                    <p className="text-gray-700">
-                                        Type your diagram request in natural language. Be as detailed or as general as you like.
-                                        You can also upload reference images for the AI to analyze and replicate.
+                    {/* Multi-Provider Support */}
+                    <h2 className="text-2xl font-semibold text-gray-900 mt-10 mb-4">
+                        Multi-Provider Support
+                    </h2>
+                    <ul className="list-disc pl-6 text-gray-700 space-y-1">
+                        <li>AWS Bedrock (default)</li>
+                        <li>
+                            OpenAI / OpenAI-compatible APIs (via{" "}
+                            <code>OPENAI_BASE_URL</code>)
+                        </li>
+                        <li>Anthropic</li>
+                        <li>Google AI</li>
+                        <li>Azure OpenAI</li>
+                        <li>Ollama</li>
+                        <li>OpenRouter</li>
+                        <li>DeepSeek</li>
+                    </ul>
+                    <p className="text-gray-700 mt-4">
+                        Note that <code>claude-sonnet-4-5</code> has trained on
+                        draw.io diagrams with AWS logos, so if you want to
+                        create AWS architecture diagrams, this is the best
+                        choice.
                     </p>
-                                </div>
-                            </div>
 
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 w-10 h-10 bg-blue-600 text-white rounded-full flex items-center justify-center font-bold mr-4">
-                                    3
+                    {/* Support */}
+                    <div className="flex items-center gap-4 mt-10 mb-4">
+                        <h2 className="text-2xl font-semibold text-gray-900">
+                            Support &amp; Contact
+                        </h2>
+                        <iframe
+                            src="https://github.com/sponsors/DayuanJiang/button"
+                            title="Sponsor DayuanJiang"
+                            height="32"
+                            width="114"
+                            style={{ border: 0, borderRadius: 6 }}
+                        />
                     </div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">AI Generates Your Diagram</h3>
                     <p className="text-gray-700">
-                                        The AI processes your request and automatically creates your diagram in seconds.
-                                        Watch as it appears in the editor with proper symbols, layouts, and connections.
+                        If you find this project useful, please consider{" "}
+                        <a
+                            href="https://github.com/sponsors/DayuanJiang"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="text-blue-600 hover:underline"
+                        >
+                            sponsoring
+                        </a>{" "}
+                        to help host the live demo site!
+                    </p>
+                    <p className="text-gray-700 mt-2">
+                        For support or inquiries, please open an issue on the{" "}
+                        <a
+                            href="https://github.com/DayuanJiang/next-ai-draw-io"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="text-blue-600 hover:underline"
+                        >
+                            GitHub repository
+                        </a>{" "}
+                        or contact: me[at]jiang.jp
                     </p>
-                                </div>
-                            </div>
 
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 w-10 h-10 bg-blue-600 text-white rounded-full flex items-center justify-center font-bold mr-4">
-                                    4
-                                </div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Refine and Export</h3>
-                                    <p className="text-gray-700">
-                                        Request modifications using the chat, manually edit in draw.io, or export to PNG, SVG,
-                                        or XML format. Access diagram history to restore previous versions anytime.
-                                    </p>
-                                </div>
-                            </div>
-                        </div>
-                    </section>
-
-                    {/* Benefits */}
-                    <section className="mb-12">
-                        <h2 className="text-2xl font-semibold text-gray-900 mb-6">Why Choose Next AI Draw.io?</h2>
-                        <div className="grid md:grid-cols-2 gap-6">
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 text-blue-600 text-2xl mr-3">⚡</div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Save Time</h3>
-                                    <p className="text-gray-700">
-                                        Create complex diagrams in seconds instead of hours. No more dragging, aligning,
-                                        or searching for the right symbols—AI handles it all.
-                                    </p>
-                                </div>
-                            </div>
-
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 text-blue-600 text-2xl mr-3">🎯</div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Precision Editing</h3>
-                                    <p className="text-gray-700">
-                                        Targeted XML editing ensures changes are precise and predictable, unlike tools
-                                        that regenerate entire diagrams and lose your layout.
-                                    </p>
-                                </div>
-                            </div>
-
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 text-blue-600 text-2xl mr-3">🆓</div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Completely Free</h3>
-                                    <p className="text-gray-700">
-                                        No subscriptions, no usage limits, no hidden costs. Open-source and free forever.
-                                        Use it for personal projects, work, or education.
-                                    </p>
-                                </div>
-                            </div>
-
-                            <div className="flex items-start">
-                                <div className="flex-shrink-0 text-blue-600 text-2xl mr-3">🔒</div>
-                                <div>
-                                    <h3 className="text-lg font-semibold text-gray-900 mb-2">Privacy First</h3>
-                                    <p className="text-gray-700">
-                                        No account required means your diagrams stay private. Work on sensitive
-                                        architecture designs without worrying about data storage or privacy policies.
-                                    </p>
-                                </div>
-                            </div>
-                        </div>
-                    </section>
-
-                    {/* CTA Section */}
-                    <section className="bg-blue-600 text-white p-8 rounded-lg text-center">
-                        <h2 className="text-3xl font-bold mb-4">Ready to Create Your First AI Diagram?</h2>
-                        <p className="text-xl mb-6">
-                            Start generating professional diagrams in seconds. No signup required.
-                        </p>
+                    {/* CTA */}
+                    <div className="mt-12 text-center">
                         <Link
                             href="/"
-                            className="inline-block bg-white text-blue-600 px-8 py-3 rounded-lg font-semibold hover:bg-gray-100 transition-colors"
+                            className="inline-block bg-blue-600 text-white px-8 py-3 rounded-lg font-semibold hover:bg-blue-700 transition-colors"
                         >
                             Open Editor
                         </Link>
-                    </section>
+                    </div>
                 </article>
             </main>
 
             {/* Footer */}
             <footer className="bg-white border-t border-gray-200 mt-16">
-                <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
-                    <div className="text-center text-gray-600 text-sm">
-                        <p className="mb-2">
-                            Next AI Draw.io - Free AI-Powered Diagram Generator
+                <div className="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-6">
+                    <p className="text-center text-gray-600 text-sm">
+                        Next AI Draw.io - Open Source AI-Powered Diagram
+                        Generator
                     </p>
-                        <p>
-                            Perfect for developers, architects, students, and business analysts.
-                            Open source. No login required.
-                        </p>
-                    </div>
                 </div>
             </footer>
         </div>
-    );
+    )
 }

app/api/chat/route.ts

@@ -1,195 +1,390 @@
-import { streamText, convertToModelMessages } from 'ai';
-import { getAIModel } from '@/lib/ai-providers';
-import { z } from "zod";
+import {
+    convertToModelMessages,
+    createUIMessageStream,
+    createUIMessageStreamResponse,
+    streamText,
+} from "ai"
+import { z } from "zod"
+import { getAIModel } from "@/lib/ai-providers"
+import { findCachedResponse } from "@/lib/cached-responses"
+import {
+    getTelemetryConfig,
+    setTraceInput,
+    setTraceOutput,
+    wrapWithObserve,
+} from "@/lib/langfuse"
+import { getSystemPrompt } from "@/lib/system-prompts"
 
-export const maxDuration = 60;
+export const maxDuration = 60
 
-export async function POST(req: Request) {
-  try {
-    const { messages, xml } = await req.json();
+// File upload limits (must match client-side)
+const MAX_FILE_SIZE = 2 * 1024 * 1024 // 2MB
+const MAX_FILES = 5
 
-    const systemMessage = `
-You are an expert diagram creation assistant specializing in draw.io XML generation.
-Your primary function is crafting clear, well-organized visual diagrams through precise XML specifications.
-You can see the image that user uploaded.
-Note that when you need to generate diagram about aws architecture, use **AWS 2025 icons**.
+// Helper function to validate file parts in messages
+function validateFileParts(messages: any[]): {
+    valid: boolean
+    error?: string
+} {
+    const lastMessage = messages[messages.length - 1]
+    const fileParts =
+        lastMessage?.parts?.filter((p: any) => p.type === "file") || []
 
-You utilize the following tools:
----Tool1---
-tool name: display_diagram
-description: Display a NEW diagram on draw.io. Use this when creating a diagram from scratch or when major structural changes are needed.
-parameters: {
-  xml: string
+    if (fileParts.length > MAX_FILES) {
+        return {
+            valid: false,
+            error: `Too many files. Maximum ${MAX_FILES} allowed.`,
+        }
+    }
+
+    for (const filePart of fileParts) {
+        // Data URLs format: data:image/png;base64,<data>
+        // Base64 increases size by ~33%, so we check the decoded size
+        if (filePart.url?.startsWith("data:")) {
+            const base64Data = filePart.url.split(",")[1]
+            if (base64Data) {
+                const sizeInBytes = Math.ceil((base64Data.length * 3) / 4)
+                if (sizeInBytes > MAX_FILE_SIZE) {
+                    return {
+                        valid: false,
+                        error: `File exceeds ${MAX_FILE_SIZE / 1024 / 1024}MB limit.`,
+                    }
+                }
+            }
+        }
+    }
+
+    return { valid: true }
 }
----Tool2---
-tool name: edit_diagram
-description: Edit specific parts of the EXISTING diagram. Use this when making small targeted changes like adding/removing elements, changing labels, or adjusting properties. This is more efficient than regenerating the entire diagram.
-parameters: {
-  edits: Array<{search: string, replace: string}>
+
+// Helper function to check if diagram is minimal/empty
+function isMinimalDiagram(xml: string): boolean {
+    const stripped = xml.replace(/\s/g, "")
+    return !stripped.includes('id="2"')
 }
----End of tools---
 
-IMPORTANT: Choose the right tool:
-- Use display_diagram for: Creating new diagrams, major restructuring, or when the current diagram XML is empty
-- Use edit_diagram for: Small modifications, adding/removing elements, changing text/colors, repositioning items
+// Helper function to create cached stream response
+function createCachedStreamResponse(xml: string): Response {
+    const toolCallId = `cached-${Date.now()}`
 
-Core capabilities:
-- Generate valid, well-formed XML strings for draw.io diagrams
-- Create professional flowcharts, mind maps, entity diagrams, and technical illustrations
-- Convert user descriptions into visually appealing diagrams using basic shapes and connectors
-- Apply proper spacing, alignment and visual hierarchy in diagram layouts
-- Adapt artistic concepts into abstract diagram representations using available shapes
-- Optimize element positioning to prevent overlapping and maintain readability
-- Structure complex systems into clear, organized visual components
+    const stream = createUIMessageStream({
+        execute: async ({ writer }) => {
+            writer.write({ type: "start" })
+            writer.write({
+                type: "tool-input-start",
+                toolCallId,
+                toolName: "display_diagram",
+            })
+            writer.write({
+                type: "tool-input-delta",
+                toolCallId,
+                inputTextDelta: xml,
+            })
+            writer.write({
+                type: "tool-input-available",
+                toolCallId,
+                toolName: "display_diagram",
+                input: { xml },
+            })
+            writer.write({ type: "finish" })
+        },
+    })
 
-Layout constraints:
-- CRITICAL: Keep all diagram elements within a single page viewport to avoid page breaks
-- Position all elements with x coordinates between 0-800 and y coordinates between 0-600
-- Maximum width for containers (like AWS cloud boxes): 700 pixels
-- Maximum height for containers: 550 pixels
-- Use compact, efficient layouts that fit the entire diagram in one view
-- Start positioning from reasonable margins (e.g., x=40, y=40) and keep elements grouped closely
-- For large diagrams with many elements, use vertical stacking or grid layouts that stay within bounds
-- Avoid spreading elements too far apart horizontally - users should see the complete diagram without a page break line
+    return createUIMessageStreamResponse({ stream })
+}
 
-Note that:
-- Focus on producing clean, professional diagrams that effectively communicate the intended information through thoughtful layout and design choices.
-- When artistic drawings are requested, creatively compose them using standard diagram shapes and connectors while maintaining visual clarity.
-- Return XML only via tool calls, never in text responses.
-- If user asks you to replicate a diagram based on an image, remember to match the diagram style and layout as closely as possible. Especially, pay attention to the lines and shapes, for example, if the lines are straight or curved, and if the shapes are rounded or square.
-- Note that when you need to generate diagram about aws architecture, use **AWS 2025 icons**.
+// Inner handler function
+async function handleChatRequest(req: Request): Promise<Response> {
+    // Check for access code
+    const accessCodes =
+        process.env.ACCESS_CODE_LIST?.split(",")
+            .map((code) => code.trim())
+            .filter(Boolean) || []
+    if (accessCodes.length > 0) {
+        const accessCodeHeader = req.headers.get("x-access-code")
+        if (!accessCodeHeader || !accessCodes.includes(accessCodeHeader)) {
+            return Response.json(
+                {
+                    error: "Invalid or missing access code. Please configure it in Settings.",
+                },
+                { status: 401 },
+            )
+        }
+    }
 
-When using edit_diagram tool:
-- Keep edits minimal - only include the specific line being changed plus 1-2 context lines
-- Example GOOD edit: {"search": "  <mxCell id=\"2\" value=\"Old Text\">", "replace": "  <mxCell id=\"2\" value=\"New Text\">"}
-- Example BAD edit: Including 10+ unchanged lines just to change one attribute
-- For multiple changes, use separate edits: [{"search": "line1", "replace": "new1"}, {"search": "line2", "replace": "new2"}]
-- RETRY POLICY: If edit_diagram fails because the search pattern cannot be found:
-  * You may retry edit_diagram up to 3 times with adjusted search patterns
-  * After 3 failed attempts, you MUST fall back to using display_diagram to regenerate the entire diagram
-  * The error message will indicate how many retries remain
-`;
+    const { messages, xml, sessionId } = await req.json()
 
-    const lastMessage = messages[messages.length - 1];
+    // Get user IP for Langfuse tracking
+    const forwardedFor = req.headers.get("x-forwarded-for")
+    const userId = forwardedFor?.split(",")[0]?.trim() || "anonymous"
+
+    // Validate sessionId for Langfuse (must be string, max 200 chars)
+    const validSessionId =
+        sessionId && typeof sessionId === "string" && sessionId.length <= 200
+            ? sessionId
+            : undefined
+
+    // Extract user input text for Langfuse trace
+    const currentMessage = messages[messages.length - 1]
+    const userInputText =
+        currentMessage?.parts?.find((p: any) => p.type === "text")?.text || ""
+
+    // Update Langfuse trace with input, session, and user
+    setTraceInput({
+        input: userInputText,
+        sessionId: validSessionId,
+        userId: userId,
+    })
+
+    // === FILE VALIDATION START ===
+    const fileValidation = validateFileParts(messages)
+    if (!fileValidation.valid) {
+        return Response.json({ error: fileValidation.error }, { status: 400 })
+    }
+    // === FILE VALIDATION END ===
+
+    // === CACHE CHECK START ===
+    const isFirstMessage = messages.length === 1
+    const isEmptyDiagram = !xml || xml.trim() === "" || isMinimalDiagram(xml)
+
+    if (isFirstMessage && isEmptyDiagram) {
+        const lastMessage = messages[0]
+        const textPart = lastMessage.parts?.find((p: any) => p.type === "text")
+        const filePart = lastMessage.parts?.find((p: any) => p.type === "file")
+
+        const cached = findCachedResponse(textPart?.text || "", !!filePart)
+
+        if (cached) {
+            console.log(
+                "[Cache] Returning cached response for:",
+                textPart?.text,
+            )
+            return createCachedStreamResponse(cached.xml)
+        }
+    }
+    // === CACHE CHECK END ===
+
+    // Get AI model from environment configuration
+    const { model, providerOptions, headers, modelId } = getAIModel()
+
+    // Get the appropriate system prompt based on model (extended for Opus/Haiku 4.5)
+    const systemMessage = getSystemPrompt(modelId)
+
+    const lastMessage = messages[messages.length - 1]
 
     // Extract text from the last message parts
-    const lastMessageText = lastMessage.parts?.find((part: any) => part.type === 'text')?.text || '';
+    const lastMessageText =
+        lastMessage.parts?.find((part: any) => part.type === "text")?.text || ""
 
     // Extract file parts (images) from the last message
-    const fileParts = lastMessage.parts?.filter((part: any) => part.type === 'file') || [];
+    const fileParts =
+        lastMessage.parts?.filter((part: any) => part.type === "file") || []
 
-    const formattedTextContent = `
-Current diagram XML:
-"""xml
-${xml || ''}
-"""
-User input:
+    // User input only - XML is now in a separate cached system message
+    const formattedUserInput = `User input:
 """md
 ${lastMessageText}
-"""`;
+"""`
 
     // Convert UIMessages to ModelMessages and add system message
-    const modelMessages = convertToModelMessages(messages);
-    let enhancedMessages = [...modelMessages];
+    const modelMessages = convertToModelMessages(messages)
 
-    // Update the last message with formatted content if it's a user message
+    // Filter out messages with empty content arrays (Bedrock API rejects these)
+    // This is a safety measure - ideally convertToModelMessages should handle all cases
+    let enhancedMessages = modelMessages.filter(
+        (msg: any) =>
+            msg.content && Array.isArray(msg.content) && msg.content.length > 0,
+    )
+
+    // Update the last message with user input only (XML moved to separate cached system message)
     if (enhancedMessages.length >= 1) {
-      const lastModelMessage = enhancedMessages[enhancedMessages.length - 1];
-      if (lastModelMessage.role === 'user') {
-        // Build content array with text and file parts
+        const lastModelMessage = enhancedMessages[enhancedMessages.length - 1]
+        if (lastModelMessage.role === "user") {
+            // Build content array with user input text and file parts
             const contentParts: any[] = [
-          { type: 'text', text: formattedTextContent }
-        ];
+                { type: "text", text: formattedUserInput },
+            ]
 
             // Add image parts back
             for (const filePart of fileParts) {
                 contentParts.push({
-            type: 'image',
+                    type: "image",
                     image: filePart.url,
-            mimeType: filePart.mediaType
-          });
+                    mimeType: filePart.mediaType,
+                })
             }
 
             enhancedMessages = [
                 ...enhancedMessages.slice(0, -1),
-          { ...lastModelMessage, content: contentParts }
-        ];
+                { ...lastModelMessage, content: contentParts },
+            ]
         }
     }
 
-    console.log("Enhanced messages:", enhancedMessages);
+    // Add cache point to the last assistant message in conversation history
+    // This caches the entire conversation prefix for subsequent requests
+    // Strategy: system (cached) + history with last assistant (cached) + new user message
+    if (enhancedMessages.length >= 2) {
+        // Find the last assistant message (should be second-to-last, before current user message)
+        for (let i = enhancedMessages.length - 2; i >= 0; i--) {
+            if (enhancedMessages[i].role === "assistant") {
+                enhancedMessages[i] = {
+                    ...enhancedMessages[i],
+                    providerOptions: {
+                        bedrock: { cachePoint: { type: "default" } },
+                    },
+                }
+                break // Only cache the last assistant message
+            }
+        }
+    }
 
-    // Get AI model from environment configuration
-    const { model, providerOptions } = getAIModel();
+    // System messages with multiple cache breakpoints for optimal caching:
+    // - Breakpoint 1: Static instructions (~1500 tokens) - rarely changes
+    // - Breakpoint 2: Current XML context - changes per diagram, but constant within a conversation turn
+    // This allows: if only user message changes, both system caches are reused
+    //              if XML changes, instruction cache is still reused
+    const systemMessages = [
+        // Cache breakpoint 1: Instructions (rarely change)
+        {
+            role: "system" as const,
+            content: systemMessage,
+            providerOptions: {
+                bedrock: { cachePoint: { type: "default" } },
+            },
+        },
+        // Cache breakpoint 2: Current diagram XML context
+        {
+            role: "system" as const,
+            content: `Current diagram XML:\n"""xml\n${xml || ""}\n"""\nWhen using edit_diagram, COPY search patterns exactly from this XML - attribute order matters!`,
+            providerOptions: {
+                bedrock: { cachePoint: { type: "default" } },
+            },
+        },
+    ]
+
+    const allMessages = [...systemMessages, ...enhancedMessages]
 
     const result = streamText({
         model,
-      system: systemMessage,
-      messages: enhancedMessages,
+        messages: allMessages,
         ...(providerOptions && { providerOptions }),
+        ...(headers && { headers }),
+        // Langfuse telemetry config (returns undefined if not configured)
+        ...(getTelemetryConfig({ sessionId: validSessionId, userId }) && {
+            experimental_telemetry: getTelemetryConfig({
+                sessionId: validSessionId,
+                userId,
+            }),
+        }),
+        onFinish: ({ text, usage, providerMetadata }) => {
+            console.log(
+                "[Cache] Full providerMetadata:",
+                JSON.stringify(providerMetadata, null, 2),
+            )
+            console.log("[Cache] Usage:", JSON.stringify(usage, null, 2))
+            // Pass usage to Langfuse (Bedrock streaming doesn't auto-report tokens to telemetry)
+            // AI SDK uses inputTokens/outputTokens, Langfuse expects promptTokens/completionTokens
+            setTraceOutput(text, {
+                promptTokens: usage?.inputTokens,
+                completionTokens: usage?.outputTokens,
+            })
+        },
         tools: {
             // Client-side tool that will be executed on the client
             display_diagram: {
-          description: `Display a diagram on draw.io. You only need to pass the nodes inside the <root> tag (including the <root> tag itself) in the XML string.
-          For example:
-          <root>
+                description: `Display a diagram on draw.io. Pass the XML content inside <root> tags.
+
+VALIDATION RULES (XML will be rejected if violated):
+1. All mxCell elements must be DIRECT children of <root> - never nested
+2. Every mxCell needs a unique id
+3. Every mxCell (except id="0") needs a valid parent attribute
+4. Edge source/target must reference existing cell IDs
+5. Escape special chars in values: &lt; &gt; &amp; &quot;
+6. Always start with: <mxCell id="0"/><mxCell id="1" parent="0"/>
+
+Example with swimlanes and edges (note: all mxCells are siblings):
+<root>
   <mxCell id="0"/>
   <mxCell id="1" parent="0"/>
-            <mxGeometry x="20" y="20" width="100" height="100" as="geometry"/>
-            <mxCell id="2" value="Hello, World!" style="shape=rectangle" parent="1">
-              <mxGeometry x="20" y="20" width="100" height="100" as="geometry"/>
+  <mxCell id="lane1" value="Frontend" style="swimlane;" vertex="1" parent="1">
+    <mxGeometry x="40" y="40" width="200" height="200" as="geometry"/>
   </mxCell>
-          </root>
-          - Note that when you need to generate diagram about aws architecture, use **AWS 2025 icons**.
-          - If you are asked to generate animated connectors, make sure to include "flowAnimation=1" in the style of the connector elements.
-          `,
+  <mxCell id="step1" value="Step 1" style="rounded=1;" vertex="1" parent="lane1">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <mxCell id="lane2" value="Backend" style="swimlane;" vertex="1" parent="1">
+    <mxGeometry x="280" y="40" width="200" height="200" as="geometry"/>
+  </mxCell>
+  <mxCell id="step2" value="Step 2" style="rounded=1;" vertex="1" parent="lane2">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;" edge="1" parent="1" source="step1" target="step2">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+</root>
+
+Notes:
+- For AWS diagrams, use **AWS 2025 icons**.
+- For animated connectors, add "flowAnimation=1" to edge style.
+`,
                 inputSchema: z.object({
-            xml: z.string().describe("XML string to be displayed on draw.io")
-          })
+                    xml: z
+                        .string()
+                        .describe("XML string to be displayed on draw.io"),
+                }),
             },
             edit_diagram: {
                 description: `Edit specific parts of the current diagram by replacing exact line matches. Use this tool to make targeted fixes without regenerating the entire XML.
+CRITICAL: Copy-paste the EXACT search pattern from the "Current diagram XML" in system context. Do NOT reorder attributes or reformat - the attribute order in draw.io XML varies and you MUST match it exactly.
 IMPORTANT: Keep edits concise:
+- COPY the exact mxCell line from the current XML (attribute order matters!)
 - Only include the lines that are changing, plus 1-2 surrounding lines for context if needed
 - Break large changes into multiple smaller edits
 - Each search must contain complete lines (never truncate mid-line)
 - First match only - be specific enough to target the right element`,
                 inputSchema: z.object({
-            edits: z.array(z.object({
-              search: z.string().describe("Exact lines to search for (including whitespace and indentation)"),
-              replace: z.string().describe("Replacement lines")
-            })).describe("Array of search/replace pairs to apply sequentially")
-          })
+                    edits: z
+                        .array(
+                            z.object({
+                                search: z
+                                    .string()
+                                    .describe(
+                                        "EXACT lines copied from current XML (preserve attribute order!)",
+                                    ),
+                                replace: z
+                                    .string()
+                                    .describe("Replacement lines"),
+                            }),
+                        )
+                        .describe(
+                            "Array of search/replace pairs to apply sequentially",
+                        ),
+                }),
             },
         },
         temperature: 0,
-    });
+    })
 
-    // Error handler function to provide detailed error messages
-    function errorHandler(error: unknown) {
-      if (error == null) {
-        return 'unknown error';
-      }
+    return result.toUIMessageStreamResponse()
+}
 
-      if (typeof error === 'string') {
-        return error;
-      }
-
-      if (error instanceof Error) {
-        return error.message;
-      }
-
-      return JSON.stringify(error);
-    }
-
-    return result.toUIMessageStreamResponse({
-      onError: errorHandler,
-    });
+// Wrap handler with error handling
+async function safeHandler(req: Request): Promise<Response> {
+    try {
+        return await handleChatRequest(req)
     } catch (error) {
-    console.error('Error in chat route:', error);
+        console.error("Error in chat route:", error)
         return Response.json(
-      { error: 'Internal server error' },
-      { status: 500 }
-    );
+            { error: "Internal server error" },
+            { status: 500 },
+        )
     }
 }
+
+// Wrap with Langfuse observe (if configured)
+const observedHandler = wrapWithObserve(safeHandler)
+
+export async function POST(req: Request) {
+    return observedHandler(req)
+}

app/api/chat/xml_guide.md

@@ -211,6 +211,7 @@ Draw.io files contain two special cells that are always present:
 4.  Define parent relationships correctly
 5.  Use `mxGeometry` elements to position shapes
 6.  For connectors, specify `source` and `target` attributes
+7.  **CRITICAL: All mxCell elements must be DIRECT children of `<root>`. NEVER nest mxCell inside another mxCell.**
 
 ## Common Patterns
 
@@ -234,12 +235,33 @@ To group elements, create a parent cell and set other cells' `parent` attribute
 
 ### Swimlanes
 
-Swimlanes use the `swimlane` shape style:
+Swimlanes use the `swimlane` shape style. **IMPORTANT: All mxCell elements (swimlanes, steps, and edges) must be siblings under `<root>`. Edges are NOT nested inside swimlanes or steps.**
 
 ```xml
-<mxCell id="20" value="Swimlane 1" style="swimlane;fontStyle=0;childLayout=stackLayout;horizontal=1;startSize=30;horizontalStack=0;resizeParent=1;resizeParentMax=0;resizeLast=0;collapsible=1;marginBottom=0;whiteSpace=wrap;html=1;" vertex="1" parent="1">
-  <mxGeometry x="200" y="200" width="140" height="120" as="geometry" />
-</mxCell>
+<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+  <!-- Swimlane 1 -->
+  <mxCell id="lane1" value="Frontend" style="swimlane;startSize=30;" vertex="1" parent="1">
+    <mxGeometry x="40" y="40" width="200" height="300" as="geometry"/>
+  </mxCell>
+  <!-- Swimlane 2 -->
+  <mxCell id="lane2" value="Backend" style="swimlane;startSize=30;" vertex="1" parent="1">
+    <mxGeometry x="280" y="40" width="200" height="300" as="geometry"/>
+  </mxCell>
+  <!-- Step inside lane1 (parent="lane1") -->
+  <mxCell id="step1" value="Send Request" style="rounded=1;" vertex="1" parent="lane1">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <!-- Step inside lane2 (parent="lane2") -->
+  <mxCell id="step2" value="Process" style="rounded=1;" vertex="1" parent="lane2">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <!-- Edge connecting step1 to step2 (sibling element, NOT nested inside steps) -->
+  <mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;" edge="1" parent="1" source="step1" target="step2">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+</root>
 ```
 
 ### Tables

app/api/config/route.ts

@@ -0,0 +1,12 @@
+import { NextResponse } from "next/server"
+
+export async function GET() {
+    const accessCodes =
+        process.env.ACCESS_CODE_LIST?.split(",")
+            .map((code) => code.trim())
+            .filter(Boolean) || []
+
+    return NextResponse.json({
+        accessCodeRequired: accessCodes.length > 0,
+    })
+}

app/api/log-feedback/route.ts

@@ -0,0 +1,112 @@
+import { randomUUID } from "crypto"
+import { z } from "zod"
+import { getLangfuseClient } from "@/lib/langfuse"
+
+const feedbackSchema = z.object({
+    messageId: z.string().min(1).max(200),
+    feedback: z.enum(["good", "bad"]),
+    sessionId: z.string().min(1).max(200).optional(),
+})
+
+export async function POST(req: Request) {
+    const langfuse = getLangfuseClient()
+    if (!langfuse) {
+        return Response.json({ success: true, logged: false })
+    }
+
+    // Validate input
+    let data
+    try {
+        data = feedbackSchema.parse(await req.json())
+    } catch {
+        return Response.json(
+            { success: false, error: "Invalid input" },
+            { status: 400 },
+        )
+    }
+
+    const { messageId, feedback, sessionId } = data
+
+    // Get user IP for tracking
+    const forwardedFor = req.headers.get("x-forwarded-for")
+    const userId = forwardedFor?.split(",")[0]?.trim() || "anonymous"
+
+    try {
+        // Find the most recent chat trace for this session to attach the score to
+        const tracesResponse = await langfuse.api.trace.list({
+            sessionId,
+            limit: 1,
+        })
+
+        const traces = tracesResponse.data || []
+        const latestTrace = traces[0]
+
+        if (!latestTrace) {
+            // No trace found for this session - create a standalone feedback trace
+            const traceId = randomUUID()
+            const timestamp = new Date().toISOString()
+
+            await langfuse.api.ingestion.batch({
+                batch: [
+                    {
+                        type: "trace-create",
+                        id: randomUUID(),
+                        timestamp,
+                        body: {
+                            id: traceId,
+                            name: "user-feedback",
+                            sessionId,
+                            userId,
+                            input: { messageId, feedback },
+                            metadata: {
+                                source: "feedback-button",
+                                note: "standalone - no chat trace found",
+                            },
+                            timestamp,
+                        },
+                    },
+                    {
+                        type: "score-create",
+                        id: randomUUID(),
+                        timestamp,
+                        body: {
+                            id: randomUUID(),
+                            traceId,
+                            name: "user-feedback",
+                            value: feedback === "good" ? 1 : 0,
+                            comment: `User gave ${feedback} feedback`,
+                        },
+                    },
+                ],
+            })
+        } else {
+            // Attach score to the existing chat trace
+            const timestamp = new Date().toISOString()
+
+            await langfuse.api.ingestion.batch({
+                batch: [
+                    {
+                        type: "score-create",
+                        id: randomUUID(),
+                        timestamp,
+                        body: {
+                            id: randomUUID(),
+                            traceId: latestTrace.id,
+                            name: "user-feedback",
+                            value: feedback === "good" ? 1 : 0,
+                            comment: `User gave ${feedback} feedback`,
+                        },
+                    },
+                ],
+            })
+        }
+
+        return Response.json({ success: true, logged: true })
+    } catch (error) {
+        console.error("Langfuse feedback error:", error)
+        return Response.json(
+            { success: false, error: "Failed to log feedback" },
+            { status: 500 },
+        )
+    }
+}

app/api/log-save/route.ts

@@ -0,0 +1,71 @@
+import { randomUUID } from "crypto"
+import { z } from "zod"
+import { getLangfuseClient } from "@/lib/langfuse"
+
+const saveSchema = z.object({
+    filename: z.string().min(1).max(255),
+    format: z.enum(["drawio", "png", "svg"]),
+    sessionId: z.string().min(1).max(200).optional(),
+})
+
+export async function POST(req: Request) {
+    const langfuse = getLangfuseClient()
+    if (!langfuse) {
+        return Response.json({ success: true, logged: false })
+    }
+
+    // Validate input
+    let data
+    try {
+        data = saveSchema.parse(await req.json())
+    } catch {
+        return Response.json(
+            { success: false, error: "Invalid input" },
+            { status: 400 },
+        )
+    }
+
+    const { filename, format, sessionId } = data
+
+    try {
+        const timestamp = new Date().toISOString()
+
+        // Find the most recent chat trace for this session to attach the save flag
+        const tracesResponse = await langfuse.api.trace.list({
+            sessionId,
+            limit: 1,
+        })
+
+        const traces = tracesResponse.data || []
+        const latestTrace = traces[0]
+
+        if (latestTrace) {
+            // Add a score to the existing trace to flag that user saved
+            await langfuse.api.ingestion.batch({
+                batch: [
+                    {
+                        type: "score-create",
+                        id: randomUUID(),
+                        timestamp,
+                        body: {
+                            id: randomUUID(),
+                            traceId: latestTrace.id,
+                            name: "diagram-saved",
+                            value: 1,
+                            comment: `User saved diagram as ${filename}.${format}`,
+                        },
+                    },
+                ],
+            })
+        }
+        // If no trace found, skip logging (user hasn't chatted yet)
+
+        return Response.json({ success: true, logged: !!latestTrace })
+    } catch (error) {
+        console.error("Langfuse save error:", error)
+        return Response.json(
+            { success: false, error: "Failed to log save" },
+            { status: 500 },
+        )
+    }
+}

app/globals.css

@@ -1,14 +1,15 @@
 @import "tailwindcss";
 
 @plugin "tailwindcss-animate";
+@plugin "@tailwindcss/typography";
 
 @custom-variant dark (&:is(.dark *));
 
 @theme inline {
     --color-background: var(--background);
     --color-foreground: var(--foreground);
-  --font-sans: var(--font-geist-sans);
-  --font-mono: var(--font-geist-mono);
+    --font-sans: var(--font-sans);
+    --font-mono: var(--font-mono);
     --color-sidebar-ring: var(--sidebar-ring);
     --color-sidebar-border: var(--sidebar-border);
     --color-sidebar-accent-foreground: var(--sidebar-accent-foreground);
@@ -45,72 +46,102 @@
 }
 
 :root {
-  --radius: 0.625rem;
-  --background: oklch(1 0 0);
-  --foreground: oklch(0.145 0 0);
+    --radius: 0.75rem;
+
+    /* Clean Light Modern Palette */
+    --background: oklch(0.985 0.002 240);
+    --foreground: oklch(0.23 0.02 260);
+
     --card: oklch(1 0 0);
-  --card-foreground: oklch(0.145 0 0);
+    --card-foreground: oklch(0.23 0.02 260);
+
     --popover: oklch(1 0 0);
-  --popover-foreground: oklch(0.145 0 0);
-  --primary: oklch(0.205 0 0);
-  --primary-foreground: oklch(0.985 0 0);
-  --secondary: oklch(0.97 0 0);
-  --secondary-foreground: oklch(0.205 0 0);
-  --muted: oklch(0.97 0 0);
-  --muted-foreground: oklch(0.556 0 0);
-  --accent: oklch(0.97 0 0);
-  --accent-foreground: oklch(0.205 0 0);
-  --destructive: oklch(0.577 0.245 27.325);
-  --border: oklch(0.922 0 0);
-  --input: oklch(0.922 0 0);
-  --ring: oklch(0.708 0 0);
-  --chart-1: oklch(0.646 0.222 41.116);
-  --chart-2: oklch(0.6 0.118 184.704);
-  --chart-3: oklch(0.398 0.07 227.392);
-  --chart-4: oklch(0.828 0.189 84.429);
-  --chart-5: oklch(0.769 0.188 70.08);
-  --sidebar: oklch(0.985 0 0);
-  --sidebar-foreground: oklch(0.145 0 0);
-  --sidebar-primary: oklch(0.205 0 0);
-  --sidebar-primary-foreground: oklch(0.985 0 0);
-  --sidebar-accent: oklch(0.97 0 0);
-  --sidebar-accent-foreground: oklch(0.205 0 0);
-  --sidebar-border: oklch(0.922 0 0);
-  --sidebar-ring: oklch(0.708 0 0);
+    --popover-foreground: oklch(0.23 0.02 260);
+
+    /* Dark primary - slightly lighter */
+    --primary: oklch(0.35 0.01 260);
+    --primary-foreground: oklch(0.99 0 0);
+
+    /* Warm gray secondary */
+    --secondary: oklch(0.96 0.005 260);
+    --secondary-foreground: oklch(0.35 0.02 260);
+
+    /* Light muted tones */
+    --muted: oklch(0.965 0.005 260);
+    --muted-foreground: oklch(0.5 0.02 260);
+
+    /* Soft lavender accent */
+    --accent: oklch(0.94 0.03 280);
+    --accent-foreground: oklch(0.35 0.08 270);
+
+    /* Coral destructive */
+    --destructive: oklch(0.6 0.2 25);
+
+    /* Subtle borders */
+    --border: oklch(0.92 0.01 260);
+    --input: oklch(0.94 0.01 260);
+    --ring: oklch(0.25 0.01 260);
+
+    /* Chart colors - harmonious palette */
+    --chart-1: oklch(0.55 0.18 265);
+    --chart-2: oklch(0.65 0.15 170);
+    --chart-3: oklch(0.7 0.18 45);
+    --chart-4: oklch(0.6 0.2 330);
+    --chart-5: oklch(0.5 0.15 200);
+
+    /* Sidebar */
+    --sidebar: oklch(0.99 0.002 260);
+    --sidebar-foreground: oklch(0.23 0.02 260);
+    --sidebar-primary: oklch(0.55 0.18 265);
+    --sidebar-primary-foreground: oklch(0.99 0 0);
+    --sidebar-accent: oklch(0.96 0.02 270);
+    --sidebar-accent-foreground: oklch(0.35 0.05 265);
+    --sidebar-border: oklch(0.93 0.01 260);
+    --sidebar-ring: oklch(0.55 0.18 265);
 }
 
 .dark {
-  --background: oklch(0.145 0 0);
-  --foreground: oklch(0.985 0 0);
-  --card: oklch(0.205 0 0);
-  --card-foreground: oklch(0.985 0 0);
-  --popover: oklch(0.205 0 0);
-  --popover-foreground: oklch(0.985 0 0);
-  --primary: oklch(0.922 0 0);
-  --primary-foreground: oklch(0.205 0 0);
-  --secondary: oklch(0.269 0 0);
-  --secondary-foreground: oklch(0.985 0 0);
-  --muted: oklch(0.269 0 0);
-  --muted-foreground: oklch(0.708 0 0);
-  --accent: oklch(0.269 0 0);
-  --accent-foreground: oklch(0.985 0 0);
-  --destructive: oklch(0.704 0.191 22.216);
-  --border: oklch(1 0 0 / 10%);
-  --input: oklch(1 0 0 / 15%);
-  --ring: oklch(0.556 0 0);
-  --chart-1: oklch(0.488 0.243 264.376);
-  --chart-2: oklch(0.696 0.17 162.48);
-  --chart-3: oklch(0.769 0.188 70.08);
-  --chart-4: oklch(0.627 0.265 303.9);
-  --chart-5: oklch(0.645 0.246 16.439);
-  --sidebar: oklch(0.205 0 0);
-  --sidebar-foreground: oklch(0.985 0 0);
-  --sidebar-primary: oklch(0.488 0.243 264.376);
-  --sidebar-primary-foreground: oklch(0.985 0 0);
-  --sidebar-accent: oklch(0.269 0 0);
-  --sidebar-accent-foreground: oklch(0.985 0 0);
-  --sidebar-border: oklch(1 0 0 / 10%);
-  --sidebar-ring: oklch(0.556 0 0);
+    --background: oklch(0.15 0.015 260);
+    --foreground: oklch(0.95 0.01 260);
+
+    --card: oklch(0.2 0.015 260);
+    --card-foreground: oklch(0.95 0.01 260);
+
+    --popover: oklch(0.2 0.015 260);
+    --popover-foreground: oklch(0.95 0.01 260);
+
+    --primary: oklch(0.7 0.16 265);
+    --primary-foreground: oklch(0.15 0.02 260);
+
+    --secondary: oklch(0.25 0.015 260);
+    --secondary-foreground: oklch(0.9 0.01 260);
+
+    --muted: oklch(0.25 0.015 260);
+    --muted-foreground: oklch(0.65 0.02 260);
+
+    --accent: oklch(0.3 0.04 280);
+    --accent-foreground: oklch(0.9 0.03 270);
+
+    --destructive: oklch(0.65 0.22 25);
+
+    --border: oklch(0.28 0.015 260);
+    --input: oklch(0.25 0.015 260);
+    --ring: oklch(0.7 0.16 265);
+
+    --chart-1: oklch(0.7 0.16 265);
+    --chart-2: oklch(0.7 0.13 170);
+    --chart-3: oklch(0.75 0.16 45);
+    --chart-4: oklch(0.7 0.18 330);
+    --chart-5: oklch(0.6 0.13 200);
+
+    --sidebar: oklch(0.18 0.015 260);
+    --sidebar-foreground: oklch(0.95 0.01 260);
+    --sidebar-primary: oklch(0.7 0.16 265);
+    --sidebar-primary-foreground: oklch(0.15 0.02 260);
+    --sidebar-accent: oklch(0.25 0.03 270);
+    --sidebar-accent-foreground: oklch(0.9 0.02 265);
+    --sidebar-border: oklch(0.28 0.015 260);
+    --sidebar-ring: oklch(0.7 0.16 265);
 }
 
 @layer base {
@@ -118,6 +149,111 @@
         @apply border-border outline-ring/50;
     }
     body {
-    @apply bg-background text-foreground;
+        @apply bg-background text-foreground font-sans;
     }
 }
+
+/* Fix for Radix ScrollArea viewport horizontal overflow */
+[data-slot="scroll-area-viewport"] > div {
+    display: block !important;
+    width: 100% !important;
+}
+
+/* Custom scrollbar */
+@layer utilities {
+    .scrollbar-thin {
+        scrollbar-width: thin;
+        scrollbar-color: oklch(0.85 0.01 260) transparent;
+    }
+
+    .scrollbar-thin::-webkit-scrollbar {
+        width: 6px;
+    }
+
+    .scrollbar-thin::-webkit-scrollbar-track {
+        background: transparent;
+    }
+
+    .scrollbar-thin::-webkit-scrollbar-thumb {
+        background-color: oklch(0.85 0.01 260);
+        border-radius: 3px;
+    }
+
+    .scrollbar-thin::-webkit-scrollbar-thumb:hover {
+        background-color: oklch(0.75 0.01 260);
+    }
+}
+
+/* Smooth page transitions */
+@keyframes fadeIn {
+    from {
+        opacity: 0;
+        transform: translateY(8px);
+    }
+    to {
+        opacity: 1;
+        transform: translateY(0);
+    }
+}
+
+@keyframes slideInRight {
+    from {
+        opacity: 0;
+        transform: translateX(16px);
+    }
+    to {
+        opacity: 1;
+        transform: translateX(0);
+    }
+}
+
+.animate-fade-in {
+    animation: fadeIn 0.3s ease-out forwards;
+}
+
+.animate-slide-in-right {
+    animation: slideInRight 0.3s ease-out forwards;
+}
+
+/* Message bubble animations */
+@keyframes messageIn {
+    from {
+        opacity: 0;
+        transform: translateY(12px) scale(0.98);
+    }
+    to {
+        opacity: 1;
+        transform: translateY(0) scale(1);
+    }
+}
+
+.animate-message-in {
+    animation: messageIn 0.25s ease-out forwards;
+}
+
+/* Subtle floating shadow for cards */
+.shadow-soft {
+    box-shadow:
+        0 1px 2px oklch(0.23 0.02 260 / 0.04),
+        0 4px 12px oklch(0.23 0.02 260 / 0.06),
+        0 8px 24px oklch(0.23 0.02 260 / 0.04);
+}
+
+.shadow-soft-lg {
+    box-shadow:
+        0 2px 4px oklch(0.23 0.02 260 / 0.04),
+        0 8px 20px oklch(0.23 0.02 260 / 0.08),
+        0 16px 40px oklch(0.23 0.02 260 / 0.06);
+}
+
+/* Gradient text utility */
+.text-gradient-primary {
+    background: linear-gradient(
+        135deg,
+        oklch(0.55 0.18 265),
+        oklch(0.6 0.2 290)
+    );
+    -webkit-background-clip: text;
+    -webkit-text-fill-color: transparent;
+    background-clip: text;
+}

app/layout.tsx

@@ -1,31 +1,53 @@
-import type { Metadata } from "next";
-import { Geist, Geist_Mono } from "next/font/google";
-import { Analytics } from "@vercel/analytics/react";
-import { DiagramProvider } from "@/contexts/diagram-context";
+import { GoogleAnalytics } from "@next/third-parties/google"
+import { Analytics } from "@vercel/analytics/react"
+import type { Metadata, Viewport } from "next"
+import { JetBrains_Mono, Plus_Jakarta_Sans } from "next/font/google"
+import { DiagramProvider } from "@/contexts/diagram-context"
 
-import "./globals.css";
+import "./globals.css"
 
-const geistSans = Geist({
-    variable: "--font-geist-sans",
+const plusJakarta = Plus_Jakarta_Sans({
+    variable: "--font-sans",
     subsets: ["latin"],
-});
+    weight: ["400", "500", "600", "700"],
+})
 
-const geistMono = Geist_Mono({
-    variable: "--font-geist-mono",
+const jetbrainsMono = JetBrains_Mono({
+    variable: "--font-mono",
     subsets: ["latin"],
-});
+    weight: ["400", "500"],
+})
+
+export const viewport: Viewport = {
+    width: "device-width",
+    initialScale: 1,
+    maximumScale: 1,
+    userScalable: false,
+}
 
 export const metadata: Metadata = {
     title: "Next AI Draw.io - AI-Powered Diagram Generator",
-    description: "Create AWS architecture diagrams, flowcharts, and technical diagrams using AI. Free online tool integrating draw.io with AI assistance for professional diagram creation.",
-    keywords: ["AI diagram generator", "AWS architecture", "flowchart creator", "draw.io", "AI drawing tool", "technical diagrams", "diagram automation", "free diagram generator", "online diagram maker"],
+    description:
+        "Create AWS architecture diagrams, flowcharts, and technical diagrams using AI. Free online tool integrating draw.io with AI assistance for professional diagram creation.",
+    keywords: [
+        "AI diagram generator",
+        "AWS architecture",
+        "flowchart creator",
+        "draw.io",
+        "AI drawing tool",
+        "technical diagrams",
+        "diagram automation",
+        "free diagram generator",
+        "online diagram maker",
+    ],
     authors: [{ name: "Next AI Draw.io" }],
     creator: "Next AI Draw.io",
     publisher: "Next AI Draw.io",
     metadataBase: new URL("https://next-ai-drawio.jiang.jp"),
     openGraph: {
         title: "Next AI Draw.io - AI Diagram Generator",
-        description: "Create professional diagrams with AI assistance. Supports AWS architecture, flowcharts, and more.",
+        description:
+            "Create professional diagrams with AI assistance. Supports AWS architecture, flowcharts, and more.",
         type: "website",
         url: "https://next-ai-drawio.jiang.jp",
         siteName: "Next AI Draw.io",
@@ -42,7 +64,8 @@ export const metadata: Metadata = {
     twitter: {
         card: "summary_large_image",
         title: "Next AI Draw.io - AI Diagram Generator",
-        description: "Create professional diagrams with AI assistance. Free, no login required.",
+        description:
+            "Create professional diagrams with AI assistance. Free, no login required.",
         images: ["/architecture.png"],
     },
     robots: {
@@ -59,27 +82,28 @@ export const metadata: Metadata = {
     icons: {
         icon: "/favicon.ico",
     },
-};
+}
 
 export default function RootLayout({
     children,
 }: Readonly<{
-    children: React.ReactNode;
+    children: React.ReactNode
 }>) {
     const jsonLd = {
-        '@context': 'https://schema.org',
-        '@type': 'SoftwareApplication',
-        name: 'Next AI Draw.io',
-        applicationCategory: 'DesignApplication',
-        operatingSystem: 'Web Browser',
-        description: 'AI-powered diagram generator with targeted XML editing capabilities that integrates with draw.io for creating AWS architecture diagrams, flowcharts, and technical diagrams. Features diagram history, multi-provider AI support, and real-time collaboration.',
-        url: 'https://next-ai-drawio.jiang.jp',
+        "@context": "https://schema.org",
+        "@type": "SoftwareApplication",
+        name: "Next AI Draw.io",
+        applicationCategory: "DesignApplication",
+        operatingSystem: "Web Browser",
+        description:
+            "AI-powered diagram generator with targeted XML editing capabilities that integrates with draw.io for creating AWS architecture diagrams, flowcharts, and technical diagrams. Features diagram history, multi-provider AI support, and real-time collaboration.",
+        url: "https://next-ai-drawio.jiang.jp",
         offers: {
-            '@type': 'Offer',
-            price: '0',
-            priceCurrency: 'USD',
+            "@type": "Offer",
+            price: "0",
+            priceCurrency: "USD",
         },
-    };
+    }
 
     return (
         <html lang="en">
@@ -90,12 +114,14 @@ export default function RootLayout({
                 />
             </head>
             <body
-                className={`${geistSans.variable} ${geistMono.variable} antialiased`}
+                className={`${plusJakarta.variable} ${jetbrainsMono.variable} antialiased`}
             >
                 <DiagramProvider>{children}</DiagramProvider>
-
                 <Analytics />
             </body>
+            {process.env.NEXT_PUBLIC_GA_ID && (
+                <GoogleAnalytics gaId={process.env.NEXT_PUBLIC_GA_ID} />
+            )}
         </html>
-    );
+    )
 }

app/page.tsx

@@ -1,63 +1,97 @@
-"use client";
-import React, { useState, useEffect } from "react";
-import { DrawIoEmbed } from "react-drawio";
-import ChatPanel from "@/components/chat-panel";
-import { useDiagram } from "@/contexts/diagram-context";
+"use client"
+import { useEffect, useRef, useState } from "react"
+import { DrawIoEmbed } from "react-drawio"
+import type { ImperativePanelHandle } from "react-resizable-panels"
+import ChatPanel from "@/components/chat-panel"
+import {
+    ResizableHandle,
+    ResizablePanel,
+    ResizablePanelGroup,
+} from "@/components/ui/resizable"
+import { useDiagram } from "@/contexts/diagram-context"
 
 export default function Home() {
-    const { drawioRef, handleDiagramExport } = useDiagram();
-    const [isMobile, setIsMobile] = useState(false);
-    const [isChatVisible, setIsChatVisible] = useState(true);
+    const { drawioRef, handleDiagramExport } = useDiagram()
+    const [isMobile, setIsMobile] = useState(false)
+    const [isChatVisible, setIsChatVisible] = useState(true)
+    const [drawioUi, setDrawioUi] = useState<"min" | "sketch">(() => {
+        if (typeof window !== "undefined") {
+            const saved = localStorage.getItem("drawio-theme")
+            if (saved === "min" || saved === "sketch") return saved
+        }
+        return "min"
+    })
+    const chatPanelRef = useRef<ImperativePanelHandle>(null)
 
     useEffect(() => {
         const checkMobile = () => {
-            setIsMobile(window.innerWidth < 768);
-        };
+            setIsMobile(window.innerWidth < 768)
+        }
 
-        // Check on mount
-        checkMobile();
+        checkMobile()
+        window.addEventListener("resize", checkMobile)
+        return () => window.removeEventListener("resize", checkMobile)
+    }, [])
 
-        // Add event listener for resize
-        window.addEventListener("resize", checkMobile);
+    const toggleChatPanel = () => {
+        const panel = chatPanelRef.current
+        if (panel) {
+            if (panel.isCollapsed()) {
+                panel.expand()
+                setIsChatVisible(true)
+            } else {
+                panel.collapse()
+                setIsChatVisible(false)
+            }
+        }
+    }
 
-        // Cleanup
-        return () => window.removeEventListener("resize", checkMobile);
-    }, []);
-
-    // Add keyboard shortcut for toggling chat panel (Ctrl+B)
     useEffect(() => {
         const handleKeyDown = (event: KeyboardEvent) => {
-            if ((event.ctrlKey || event.metaKey) && event.key === 'b') {
-                event.preventDefault();
-                setIsChatVisible((prev) => !prev);
+            if ((event.ctrlKey || event.metaKey) && event.key === "b") {
+                event.preventDefault()
+                toggleChatPanel()
+            }
         }
-        };
 
-        window.addEventListener('keydown', handleKeyDown);
+        window.addEventListener("keydown", handleKeyDown)
+        return () => window.removeEventListener("keydown", handleKeyDown)
+    }, [])
 
-        return () => {
-            window.removeEventListener('keydown', handleKeyDown);
-        };
-    }, []);
+    // Show confirmation dialog when user tries to leave the page
+    // This helps prevent accidental navigation from browser back gestures
+    useEffect(() => {
+        const handleBeforeUnload = (event: BeforeUnloadEvent) => {
+            event.preventDefault()
+            return ""
+        }
+
+        window.addEventListener("beforeunload", handleBeforeUnload)
+        return () =>
+            window.removeEventListener("beforeunload", handleBeforeUnload)
+    }, [])
 
     return (
-        <div className="flex h-screen bg-gray-100 relative">
-            {/* Mobile warning overlay - keeps components mounted */}
-            {isMobile && (
-                <div className="absolute inset-0 z-50 flex items-center justify-center bg-gray-100">
-                    <div className="text-center p-8">
-                        <h1 className="text-2xl font-semibold text-gray-800">
-                            Please open this application on a desktop or laptop
-                        </h1>
-                    </div>
-                </div>
-            )}
-
-            <div className={`${isChatVisible ? 'w-2/3' : 'w-full'} p-1 h-full relative transition-all duration-300 ease-in-out`}>
+        <div className="h-screen bg-background relative overflow-hidden">
+            <ResizablePanelGroup
+                key={isMobile ? "mobile" : "desktop"}
+                direction={isMobile ? "vertical" : "horizontal"}
+                className="h-full"
+            >
+                {/* Draw.io Canvas */}
+                <ResizablePanel defaultSize={isMobile ? 50 : 67} minSize={20}>
+                    <div
+                        className={`h-full relative ${
+                            isMobile ? "p-1" : "p-2"
+                        }`}
+                    >
+                        <div className="h-full rounded-xl overflow-hidden shadow-soft-lg border border-border/30 bg-white">
                             <DrawIoEmbed
+                                key={drawioUi}
                                 ref={drawioRef}
                                 onExport={handleDiagramExport}
                                 urlParameters={{
+                                    ui: drawioUi,
                                     spin: true,
                                     libraries: false,
                                     saveAndExit: false,
@@ -65,12 +99,38 @@ export default function Home() {
                                 }}
                             />
                         </div>
-            <div className={`${isChatVisible ? 'w-1/3' : 'w-12'} h-full p-1 transition-all duration-300 ease-in-out`}>
+                    </div>
+                </ResizablePanel>
+
+                <ResizableHandle withHandle />
+
+                {/* Chat Panel */}
+                <ResizablePanel
+                    ref={chatPanelRef}
+                    defaultSize={isMobile ? 50 : 33}
+                    minSize={isMobile ? 20 : 15}
+                    maxSize={isMobile ? 80 : 50}
+                    collapsible={!isMobile}
+                    collapsedSize={isMobile ? 0 : 3}
+                    onCollapse={() => setIsChatVisible(false)}
+                    onExpand={() => setIsChatVisible(true)}
+                >
+                    <div className={`h-full ${isMobile ? "p-1" : "py-2 pr-2"}`}>
                         <ChatPanel
                             isVisible={isChatVisible}
-                    onToggleVisibility={() => setIsChatVisible(!isChatVisible)}
+                            onToggleVisibility={toggleChatPanel}
+                            drawioUi={drawioUi}
+                            onToggleDrawioUi={() => {
+                                const newTheme =
+                                    drawioUi === "min" ? "sketch" : "min"
+                                localStorage.setItem("drawio-theme", newTheme)
+                                setDrawioUi(newTheme)
+                            }}
+                            isMobile={isMobile}
                         />
                     </div>
+                </ResizablePanel>
+            </ResizablePanelGroup>
         </div>
-    );
+    )
 }

app/robots.ts

@@ -1,12 +1,12 @@
-import { MetadataRoute } from 'next'
+import type { MetadataRoute } from "next"
 
 export default function robots(): MetadataRoute.Robots {
     return {
         rules: {
-            userAgent: '*',
-            allow: '/',
-            disallow: '/api/',
+            userAgent: "*",
+            allow: "/",
+            disallow: "/api/",
         },
-        sitemap: 'https://next-ai-drawio.jiang.jp/sitemap.xml',
+        sitemap: "https://next-ai-drawio.jiang.jp/sitemap.xml",
     }
 }

app/sitemap.ts

@@ -1,17 +1,17 @@
-import { MetadataRoute } from 'next'
+import type { MetadataRoute } from "next"
 
 export default function sitemap(): MetadataRoute.Sitemap {
     return [
         {
-            url: 'https://next-ai-drawio.jiang.jp',
+            url: "https://next-ai-drawio.jiang.jp",
             lastModified: new Date(),
-            changeFrequency: 'weekly',
+            changeFrequency: "weekly",
             priority: 1,
         },
         {
-            url: 'https://next-ai-drawio.jiang.jp/about',
+            url: "https://next-ai-drawio.jiang.jp/about",
             lastModified: new Date(),
-            changeFrequency: 'monthly',
+            changeFrequency: "monthly",
             priority: 0.8,
         },
     ]

biome.json

@@ -0,0 +1,83 @@
+{
+    "$schema": "https://biomejs.dev/schemas/2.3.8/schema.json",
+    "vcs": {
+        "enabled": true,
+        "clientKind": "git",
+        "useIgnoreFile": true
+    },
+    "files": {
+        "ignoreUnknown": false
+    },
+    "formatter": {
+        "enabled": true,
+        "indentStyle": "space",
+        "indentWidth": 4
+    },
+    "linter": {
+        "enabled": true,
+        "rules": {
+            "recommended": true,
+            "complexity": {
+                "noImportantStyles": "off"
+            },
+            "suspicious": {
+                "noExplicitAny": "off",
+                "noArrayIndexKey": "off",
+                "noImplicitAnyLet": "off",
+                "noAssignInExpressions": "off"
+            },
+            "a11y": {
+                "useButtonType": "off",
+                "noAutofocus": "off",
+                "noStaticElementInteractions": "off",
+                "useKeyWithClickEvents": "off",
+                "noLabelWithoutControl": "off",
+                "noNoninteractiveTabindex": "off"
+            },
+            "correctness": {
+                "useExhaustiveDependencies": "off"
+            },
+            "style": {
+                "useNodejsImportProtocol": "off",
+                "useTemplate": "off"
+            },
+            "security": {
+                "noDangerouslySetInnerHtml": "off"
+            }
+        }
+    },
+    "javascript": {
+        "formatter": {
+            "quoteStyle": "double",
+            "semicolons": "asNeeded"
+        }
+    },
+    "css": {
+        "parser": {
+            "cssModules": true,
+            "tailwindDirectives": true
+        }
+    },
+    "assist": {
+        "enabled": true,
+        "actions": {
+            "source": {
+                "organizeImports": "on"
+            }
+        }
+    },
+    "overrides": [
+        {
+            "includes": ["components/ui/**"],
+            "formatter": {
+                "enabled": false
+            },
+            "linter": {
+                "enabled": false
+            },
+            "assist": {
+                "enabled": false
+            }
+        }
+    ]
+}

components/button-with-tooltip.tsx

@@ -1,19 +1,19 @@
-import React from "react";
-import { Button, buttonVariants } from "@/components/ui/button";
+import type { VariantProps } from "class-variance-authority"
+import type React from "react"
+import { Button, type buttonVariants } from "@/components/ui/button"
 import {
     Tooltip,
     TooltipContent,
     TooltipProvider,
     TooltipTrigger,
-} from "@/components/ui/tooltip";
-import { type VariantProps } from "class-variance-authority";
+} from "@/components/ui/tooltip"
 
 interface ButtonWithTooltipProps
     extends React.ComponentProps<"button">,
         VariantProps<typeof buttonVariants> {
-    tooltipContent: string;
-    children: React.ReactNode;
-    asChild?: boolean;
+    tooltipContent: string
+    children: React.ReactNode
+    asChild?: boolean
 }
 
 export function ButtonWithTooltip({
@@ -27,8 +27,10 @@ export function ButtonWithTooltip({
                 <TooltipTrigger asChild>
                     <Button {...buttonProps}>{children}</Button>
                 </TooltipTrigger>
-                <TooltipContent>{tooltipContent}</TooltipContent>
+                <TooltipContent className="max-w-xs text-wrap">
+                    {tooltipContent}
+                </TooltipContent>
             </Tooltip>
         </TooltipProvider>
-    );
+    )
 }

components/chat-example-panel.tsx

@@ -1,82 +1,133 @@
+"use client"
+
+import { Cloud, GitBranch, Palette, Zap } from "lucide-react"
+
+interface ExampleCardProps {
+    icon: React.ReactNode
+    title: string
+    description: string
+    onClick: () => void
+}
+
+function ExampleCard({ icon, title, description, onClick }: ExampleCardProps) {
+    return (
+        <button
+            onClick={onClick}
+            className="group w-full text-left p-4 rounded-xl border border-border/60 bg-card hover:bg-accent/50 hover:border-primary/30 transition-all duration-200 hover:shadow-sm"
+        >
+            <div className="flex items-start gap-3">
+                <div className="w-9 h-9 rounded-lg bg-primary/10 flex items-center justify-center shrink-0 group-hover:bg-primary/15 transition-colors">
+                    {icon}
+                </div>
+                <div className="min-w-0">
+                    <h3 className="text-sm font-medium text-foreground group-hover:text-primary transition-colors">
+                        {title}
+                    </h3>
+                    <p className="text-xs text-muted-foreground mt-0.5 line-clamp-2">
+                        {description}
+                    </p>
+                </div>
+            </div>
+        </button>
+    )
+}
+
 export default function ExamplePanel({
     setInput,
     setFiles,
 }: {
-    setInput: (input: string) => void;
-    setFiles: (files: File[]) => void;
+    setInput: (input: string) => void
+    setFiles: (files: File[]) => void
 }) {
-    // New handler for the "Replicate this flowchart" button
     const handleReplicateFlowchart = async () => {
-        setInput("Replicate this flowchart.");
+        setInput("Replicate this flowchart.")
 
         try {
-            // Fetch the example image
-            const response = await fetch("/example.png");
-            const blob = await response.blob();
-            const file = new File([blob], "example.png", { type: "image/png" });
-
-            // Set the file to the files state
-            setFiles([file]);
+            const response = await fetch("/example.png")
+            const blob = await response.blob()
+            const file = new File([blob], "example.png", { type: "image/png" })
+            setFiles([file])
         } catch (error) {
-            console.error("Error loading example image:", error);
+            console.error("Error loading example image:", error)
+        }
     }
-    };
 
-    // Handler for the "Replicate this in aws style" button
     const handleReplicateArchitecture = async () => {
-        setInput("Replicate this in aws style");
+        setInput("Replicate this in aws style")
 
         try {
-            // Fetch the architecture image
-            const response = await fetch("/architecture.png");
-            const blob = await response.blob();
+            const response = await fetch("/architecture.png")
+            const blob = await response.blob()
             const file = new File([blob], "architecture.png", {
                 type: "image/png",
-            });
-
-            // Set the file to the files state
-            setFiles([file]);
+            })
+            setFiles([file])
         } catch (error) {
-            console.error("Error loading architecture image:", error);
+            console.error("Error loading architecture image:", error)
         }
-    };
+    }
+
     return (
-        <div className="px-4 py-2 border-t border-b border-gray-100">
-            <p className="text-sm text-gray-500 mb-2">
-                {" "}
-                Start a conversation to generate or modify diagrams.
+        <div className="py-6 px-2 animate-fade-in">
+            {/* Welcome section */}
+            <div className="text-center mb-6">
+                <h2 className="text-lg font-semibold text-foreground mb-2">
+                    Create diagrams with AI
+                </h2>
+                <p className="text-sm text-muted-foreground max-w-xs mx-auto">
+                    Describe what you want to create or upload an image to
+                    replicate
                 </p>
-            <p className="text-sm text-gray-500 mb-2">
-                {" "}
-                You can also upload images to use as references.
+            </div>
+
+            {/* Examples grid */}
+            <div className="space-y-3">
+                <p className="text-xs font-medium text-muted-foreground uppercase tracking-wider px-1">
+                    Quick Examples
                 </p>
-            <p className="text-sm text-gray-500 mb-2">Try these examples:</p>
-            <div className="flex flex-wrap gap-5">
-                <button
-                    className="text-xs bg-gray-100 hover:bg-gray-200 text-gray-800 font-medium py-1 px-2 rounded"
-                    onClick={() => setInput("Give me a **animated connector** diagram of transformer's architecture")}
-                >
-                    Draw diagram with Animated Connectors
-                </button>
-                <button
-                    className="text-xs bg-gray-100 hover:bg-gray-200 text-gray-800 font-medium py-1 px-2 rounded"
+
+                <div className="grid gap-2">
+                    <ExampleCard
+                        icon={<Zap className="w-4 h-4 text-primary" />}
+                        title="Animated Diagram"
+                        description="Draw a transformer architecture with animated connectors"
+                        onClick={() => {
+                            setInput(
+                                "Give me a **animated connector** diagram of transformer's architecture",
+                            )
+                            setFiles([])
+                        }}
+                    />
+
+                    <ExampleCard
+                        icon={<Cloud className="w-4 h-4 text-primary" />}
+                        title="AWS Architecture"
+                        description="Create a cloud architecture diagram with AWS icons"
                         onClick={handleReplicateArchitecture}
-                >
-                    Create AWS architecture
-                </button>
-                <button
-                    className="text-xs bg-gray-100 hover:bg-gray-200 text-gray-800 font-medium py-1 px-2 rounded"
+                    />
+
+                    <ExampleCard
+                        icon={<GitBranch className="w-4 h-4 text-primary" />}
+                        title="Replicate Flowchart"
+                        description="Upload and replicate an existing flowchart"
                         onClick={handleReplicateFlowchart}
-                >
-                    Replicate flowchart
-                </button>
-                <button
-                    className="text-xs bg-gray-100 hover:bg-gray-200 text-gray-800 font-medium py-1 px-2 rounded"
-                    onClick={() => setInput("Draw a cat for me")}
-                >
-                    Draw a cat
-                </button>
+                    />
+
+                    <ExampleCard
+                        icon={<Palette className="w-4 h-4 text-primary" />}
+                        title="Creative Drawing"
+                        description="Draw something fun and creative"
+                        onClick={() => {
+                            setInput("Draw a cat for me")
+                            setFiles([])
+                        }}
+                    />
+                </div>
+
+                <p className="text-[11px] text-muted-foreground/60 text-center mt-4">
+                    Examples are cached for instant response
+                </p>
             </div>
         </div>
-    );
+    )
 }

components/chat-input.tsx

@@ -1,31 +1,130 @@
-"use client";
+"use client"
 
-import React, { useCallback, useRef, useEffect, useState } from "react";
-import { Button } from "@/components/ui/button";
-import { Textarea } from "@/components/ui/textarea";
-import { ResetWarningModal } from "@/components/reset-warning-modal";
 import {
-    Loader2,
-    Send,
-    RotateCcw,
-    Image as ImageIcon,
+    Download,
     History,
-} from "lucide-react";
-import { ButtonWithTooltip } from "@/components/button-with-tooltip";
-import { FilePreviewList } from "./file-preview-list";
-import { useDiagram } from "@/contexts/diagram-context";
-import { HistoryDialog } from "@/components/history-dialog";
+    Image as ImageIcon,
+    LayoutGrid,
+    Loader2,
+    PenTool,
+    Send,
+    Trash2,
+} from "lucide-react"
+import type React from "react"
+import { useCallback, useEffect, useRef, useState } from "react"
+import { toast } from "sonner"
+import { ButtonWithTooltip } from "@/components/button-with-tooltip"
+import { ErrorToast } from "@/components/error-toast"
+import { HistoryDialog } from "@/components/history-dialog"
+import { ResetWarningModal } from "@/components/reset-warning-modal"
+import { SaveDialog } from "@/components/save-dialog"
+import { Button } from "@/components/ui/button"
+import {
+    Dialog,
+    DialogContent,
+    DialogDescription,
+    DialogFooter,
+    DialogHeader,
+    DialogTitle,
+} from "@/components/ui/dialog"
+import { Textarea } from "@/components/ui/textarea"
+import { useDiagram } from "@/contexts/diagram-context"
+import { FilePreviewList } from "./file-preview-list"
+
+const MAX_FILE_SIZE = 2 * 1024 * 1024 // 2MB
+const MAX_FILES = 5
+
+function formatFileSize(bytes: number): string {
+    const mb = bytes / 1024 / 1024
+    if (mb < 0.01) return `${(bytes / 1024).toFixed(0)}KB`
+    return `${mb.toFixed(2)}MB`
+}
+
+function showErrorToast(message: React.ReactNode) {
+    toast.custom(
+        (t) => (
+            <ErrorToast message={message} onDismiss={() => toast.dismiss(t)} />
+        ),
+        { duration: 5000 },
+    )
+}
+
+interface ValidationResult {
+    validFiles: File[]
+    errors: string[]
+}
+
+function validateFiles(
+    newFiles: File[],
+    existingCount: number,
+): ValidationResult {
+    const errors: string[] = []
+    const validFiles: File[] = []
+
+    const availableSlots = MAX_FILES - existingCount
+
+    if (availableSlots <= 0) {
+        errors.push(`Maximum ${MAX_FILES} files allowed`)
+        return { validFiles, errors }
+    }
+
+    for (const file of newFiles) {
+        if (validFiles.length >= availableSlots) {
+            errors.push(`Only ${availableSlots} more file(s) allowed`)
+            break
+        }
+        if (file.size > MAX_FILE_SIZE) {
+            errors.push(
+                `"${file.name}" is ${formatFileSize(file.size)} (exceeds 2MB)`,
+            )
+        } else {
+            validFiles.push(file)
+        }
+    }
+
+    return { validFiles, errors }
+}
+
+function showValidationErrors(errors: string[]) {
+    if (errors.length === 0) return
+
+    if (errors.length === 1) {
+        showErrorToast(
+            <span className="text-muted-foreground">{errors[0]}</span>,
+        )
+    } else {
+        showErrorToast(
+            <div className="flex flex-col gap-1">
+                <span className="font-medium">
+                    {errors.length} files rejected:
+                </span>
+                <ul className="text-muted-foreground text-xs list-disc list-inside">
+                    {errors.slice(0, 3).map((err) => (
+                        <li key={err}>{err}</li>
+                    ))}
+                    {errors.length > 3 && (
+                        <li>...and {errors.length - 3} more</li>
+                    )}
+                </ul>
+            </div>,
+        )
+    }
+}
 
 interface ChatInputProps {
-    input: string;
-    status: "submitted" | "streaming" | "ready" | "error";
-    onSubmit: (e: React.FormEvent<HTMLFormElement>) => void;
-    onChange: (e: React.ChangeEvent<HTMLTextAreaElement>) => void;
-    onClearChat: () => void;
-    files?: File[];
-    onFileChange?: (files: File[]) => void;
-    showHistory?: boolean;
-    onToggleHistory?: (show: boolean) => void;
+    input: string
+    status: "submitted" | "streaming" | "ready" | "error"
+    onSubmit: (e: React.FormEvent<HTMLFormElement>) => void
+    onChange: (e: React.ChangeEvent<HTMLTextAreaElement>) => void
+    onClearChat: () => void
+    files?: File[]
+    onFileChange?: (files: File[]) => void
+    showHistory?: boolean
+    onToggleHistory?: (show: boolean) => void
+    sessionId?: string
+    error?: Error | null
+    drawioUi?: "min" | "sketch"
+    onToggleDrawioUi?: () => void
 }
 
 export function ChatInput({
@@ -38,175 +137,196 @@ export function ChatInput({
     onFileChange = () => {},
     showHistory = false,
     onToggleHistory = () => {},
+    sessionId,
+    error = null,
+    drawioUi = "min",
+    onToggleDrawioUi = () => {},
 }: ChatInputProps) {
-    const { diagramHistory } = useDiagram();
-    const textareaRef = useRef<HTMLTextAreaElement>(null);
-    const fileInputRef = useRef<HTMLInputElement>(null);
-    const [isDragging, setIsDragging] = useState(false);
-    const [showClearDialog, setShowClearDialog] = useState(false);
+    const { diagramHistory, saveDiagramToFile } = useDiagram()
+    const textareaRef = useRef<HTMLTextAreaElement>(null)
+    const fileInputRef = useRef<HTMLInputElement>(null)
+    const [isDragging, setIsDragging] = useState(false)
+    const [showClearDialog, setShowClearDialog] = useState(false)
+    const [showSaveDialog, setShowSaveDialog] = useState(false)
+    const [showThemeWarning, setShowThemeWarning] = useState(false)
 
-    // Debug: Log status changes
-    const isDisabled = status === "streaming" || status === "submitted";
-    useEffect(() => {
-        console.log('[ChatInput] Status changed to:', status, '| Input disabled:', isDisabled);
-    }, [status, isDisabled]);
+    // Allow retry when there's an error (even if status is still "streaming" or "submitted")
+    const isDisabled =
+        (status === "streaming" || status === "submitted") && !error
 
-    // Auto-resize textarea based on content
     const adjustTextareaHeight = useCallback(() => {
-        const textarea = textareaRef.current;
+        const textarea = textareaRef.current
         if (textarea) {
-            textarea.style.height = "auto";
-            textarea.style.height = `${Math.min(textarea.scrollHeight, 200)}px`;
+            textarea.style.height = "auto"
+            textarea.style.height = `${Math.min(textarea.scrollHeight, 200)}px`
         }
-    }, []);
+    }, [])
 
+    // Handle programmatic input changes (e.g., setInput("") after form submission)
     useEffect(() => {
-        adjustTextareaHeight();
-    }, [input, adjustTextareaHeight]);
+        adjustTextareaHeight()
+    }, [input, adjustTextareaHeight])
+
+    const handleChange = (e: React.ChangeEvent<HTMLTextAreaElement>) => {
+        onChange(e)
+        adjustTextareaHeight()
+    }
 
-    // Handle keyboard shortcuts and paste events
     const handleKeyDown = (e: React.KeyboardEvent) => {
         if ((e.metaKey || e.ctrlKey) && e.key === "Enter") {
-            e.preventDefault();
-            const form = e.currentTarget.closest("form");
+            e.preventDefault()
+            const form = e.currentTarget.closest("form")
             if (form && input.trim() && !isDisabled) {
-                form.requestSubmit();
+                form.requestSubmit()
+            }
         }
     }
-    };
 
-    // Handle clipboard paste
     const handlePaste = async (e: React.ClipboardEvent) => {
-        if (isDisabled) return;
+        if (isDisabled) return
 
-        const items = e.clipboardData.items;
+        const items = e.clipboardData.items
         const imageItems = Array.from(items).filter((item) =>
-            item.type.startsWith("image/")
-        );
+            item.type.startsWith("image/"),
+        )
 
         if (imageItems.length > 0) {
-            const imageFiles = await Promise.all(
-                imageItems.map(async (item) => {
-                    const file = item.getAsFile();
-                    if (!file) return null;
-                    // Create a new file with a unique name
+            const imageFiles = (
+                await Promise.all(
+                    imageItems.map(async (item, index) => {
+                        const file = item.getAsFile()
+                        if (!file) return null
                         return new File(
                             [file],
-                        `pasted-image-${Date.now()}.${file.type.split("/")[1]}`,
-                        {
-                            type: file.type,
-                        }
-                    );
-                })
-            );
+                            `pasted-image-${Date.now()}-${index}.${file.type.split("/")[1]}`,
+                            { type: file.type },
+                        )
+                    }),
+                )
+            ).filter((f): f is File => f !== null)
 
-            const validFiles = imageFiles.filter(
-                (file): file is File => file !== null
-            );
+            const { validFiles, errors } = validateFiles(
+                imageFiles,
+                files.length,
+            )
+            showValidationErrors(errors)
             if (validFiles.length > 0) {
-                onFileChange([...files, ...validFiles]);
+                onFileChange([...files, ...validFiles])
+            }
         }
     }
-    };
 
-    // Handle file changes
     const handleFileChange = (e: React.ChangeEvent<HTMLInputElement>) => {
-        const newFiles = Array.from(e.target.files || []);
-        onFileChange([...files, ...newFiles]);
-    };
-
-    // Remove individual file
-    const handleRemoveFile = (fileToRemove: File) => {
-        onFileChange(files.filter((file) => file !== fileToRemove));
-        if (fileInputRef.current) {
-            fileInputRef.current.value = "";
+        const newFiles = Array.from(e.target.files || [])
+        const { validFiles, errors } = validateFiles(newFiles, files.length)
+        showValidationErrors(errors)
+        if (validFiles.length > 0) {
+            onFileChange([...files, ...validFiles])
+        }
+        // Reset input so same file can be selected again
+        if (fileInputRef.current) {
+            fileInputRef.current.value = ""
+        }
+    }
+
+    const handleRemoveFile = (fileToRemove: File) => {
+        onFileChange(files.filter((file) => file !== fileToRemove))
+        if (fileInputRef.current) {
+            fileInputRef.current.value = ""
+        }
     }
-    };
 
-    // Trigger file input click
     const triggerFileInput = () => {
-        fileInputRef.current?.click();
-    };
+        fileInputRef.current?.click()
+    }
 
-    // Handle drag events
     const handleDragOver = (e: React.DragEvent<HTMLFormElement>) => {
-        e.preventDefault();
-        e.stopPropagation();
-        setIsDragging(true);
-    };
+        e.preventDefault()
+        e.stopPropagation()
+        setIsDragging(true)
+    }
 
     const handleDragLeave = (e: React.DragEvent<HTMLFormElement>) => {
-        e.preventDefault();
-        e.stopPropagation();
-        setIsDragging(false);
-    };
+        e.preventDefault()
+        e.stopPropagation()
+        setIsDragging(false)
+    }
 
     const handleDrop = (e: React.DragEvent<HTMLFormElement>) => {
-        e.preventDefault();
-        e.stopPropagation();
-        setIsDragging(false);
+        e.preventDefault()
+        e.stopPropagation()
+        setIsDragging(false)
 
-        if (isDisabled) return;
+        if (isDisabled) return
 
-        const droppedFiles = e.dataTransfer.files;
-
-        // Only process image files
+        const droppedFiles = e.dataTransfer.files
         const imageFiles = Array.from(droppedFiles).filter((file) =>
-            file.type.startsWith("image/")
-        );
+            file.type.startsWith("image/"),
+        )
 
-        if (imageFiles.length > 0) {
-            onFileChange([...files, ...imageFiles]);
+        const { validFiles, errors } = validateFiles(imageFiles, files.length)
+        showValidationErrors(errors)
+        if (validFiles.length > 0) {
+            onFileChange([...files, ...validFiles])
+        }
     }
-    };
 
-    // Handle clearing conversation and diagram
     const handleClear = () => {
-        onClearChat();
-        setShowClearDialog(false);
-    };
+        onClearChat()
+        setShowClearDialog(false)
+    }
 
     return (
         <form
             onSubmit={onSubmit}
-            className={`w-full space-y-2 ${
+            className={`w-full transition-all duration-200 ${
                 isDragging
-                    ? "border-2 border-dashed border-primary p-4 rounded-lg bg-muted/20"
+                    ? "ring-2 ring-primary ring-offset-2 rounded-2xl"
                     : ""
             }`}
             onDragOver={handleDragOver}
             onDragLeave={handleDragLeave}
             onDrop={handleDrop}
         >
-            <FilePreviewList files={files} onRemoveFile={handleRemoveFile} />
+            {/* File previews */}
+            {files.length > 0 && (
+                <div className="mb-3">
+                    <FilePreviewList
+                        files={files}
+                        onRemoveFile={handleRemoveFile}
+                    />
+                </div>
+            )}
 
+            {/* Input container */}
+            <div className="relative rounded-2xl border border-border bg-background shadow-sm focus-within:ring-2 focus-within:ring-primary/20 focus-within:border-primary/50 transition-all duration-200">
                 <Textarea
                     ref={textareaRef}
                     value={input}
-                onChange={onChange}
+                    onChange={handleChange}
                     onKeyDown={handleKeyDown}
                     onPaste={handlePaste}
-                placeholder="Describe what changes you want to make to the diagram
-                or upload(paste) an image to replicate a diagram.
-                 (Press Cmd/Ctrl + Enter to send)"
+                    placeholder="Describe your diagram or paste an image..."
                     disabled={isDisabled}
                     aria-label="Chat input"
-                className="min-h-[80px] resize-none transition-all duration-200 px-1 py-0"
+                    className="min-h-[60px] max-h-[200px] resize-none border-0 bg-transparent px-4 py-3 text-sm focus-visible:ring-0 focus-visible:ring-offset-0 placeholder:text-muted-foreground/60"
                 />
 
-            <div className="flex items-center gap-2">
-                <div className="mr-auto">
+                {/* Action bar */}
+                <div className="flex items-center justify-between px-3 py-2 border-t border-border/50">
+                    {/* Left actions */}
+                    <div className="flex items-center gap-1">
                         <ButtonWithTooltip
                             type="button"
                             variant="ghost"
-                        size="icon"
+                            size="sm"
                             onClick={() => setShowClearDialog(true)}
-                        tooltipContent="Clear current conversation and diagram"
+                            tooltipContent="Clear conversation"
+                            className="h-8 w-8 p-0 text-muted-foreground hover:text-destructive hover:bg-destructive/10"
                         >
-                        <RotateCcw className="mr-2 h-4 w-4" />
+                            <Trash2 className="h-4 w-4" />
                         </ButtonWithTooltip>
 
-                    {/* Warning Modal */}
                         <ResetWarningModal
                             open={showClearDialog}
                             onOpenChange={setShowClearDialog}
@@ -217,34 +337,110 @@ export function ChatInput({
                             showHistory={showHistory}
                             onToggleHistory={onToggleHistory}
                         />
-                </div>
-                <div className="flex gap-2">
-                    {/* History Button */}
+
                         <ButtonWithTooltip
                             type="button"
-                        variant="outline"
-                        size="icon"
-                        onClick={() => onToggleHistory(true)}
-                        disabled={
-                            isDisabled ||
-                            diagramHistory.length === 0
+                            variant="ghost"
+                            size="sm"
+                            onClick={() => setShowThemeWarning(true)}
+                            tooltipContent={
+                                drawioUi === "min"
+                                    ? "Switch to Sketch theme"
+                                    : "Switch to Minimal theme"
                             }
-                        title="Diagram History"
-                        tooltipContent="View diagram history"
+                            className="h-8 w-8 p-0 text-muted-foreground hover:text-foreground"
+                        >
+                            {drawioUi === "min" ? (
+                                <PenTool className="h-4 w-4" />
+                            ) : (
+                                <LayoutGrid className="h-4 w-4" />
+                            )}
+                        </ButtonWithTooltip>
+
+                        <Dialog
+                            open={showThemeWarning}
+                            onOpenChange={setShowThemeWarning}
+                        >
+                            <DialogContent>
+                                <DialogHeader>
+                                    <DialogTitle>Switch Theme?</DialogTitle>
+                                    <DialogDescription>
+                                        Switching themes will reload the diagram
+                                        editor and clear any unsaved changes.
+                                    </DialogDescription>
+                                </DialogHeader>
+                                <DialogFooter>
+                                    <Button
+                                        variant="outline"
+                                        onClick={() =>
+                                            setShowThemeWarning(false)
+                                        }
+                                    >
+                                        Cancel
+                                    </Button>
+                                    <Button
+                                        variant="destructive"
+                                        onClick={() => {
+                                            onClearChat()
+                                            onToggleDrawioUi()
+                                            setShowThemeWarning(false)
+                                        }}
+                                    >
+                                        Switch Theme
+                                    </Button>
+                                </DialogFooter>
+                            </DialogContent>
+                        </Dialog>
+                    </div>
+
+                    {/* Right actions */}
+                    <div className="flex items-center gap-1">
+                        <ButtonWithTooltip
+                            type="button"
+                            variant="ghost"
+                            size="sm"
+                            onClick={() => onToggleHistory(true)}
+                            disabled={isDisabled || diagramHistory.length === 0}
+                            tooltipContent="Diagram history"
+                            className="h-8 w-8 p-0 text-muted-foreground hover:text-foreground"
                         >
                             <History className="h-4 w-4" />
                         </ButtonWithTooltip>
 
-                    <Button
+                        <ButtonWithTooltip
                             type="button"
-                        variant="outline"
-                        size="icon"
+                            variant="ghost"
+                            size="sm"
+                            onClick={() => setShowSaveDialog(true)}
+                            disabled={isDisabled}
+                            tooltipContent="Save diagram"
+                            className="h-8 w-8 p-0 text-muted-foreground hover:text-foreground"
+                        >
+                            <Download className="h-4 w-4" />
+                        </ButtonWithTooltip>
+
+                        <SaveDialog
+                            open={showSaveDialog}
+                            onOpenChange={setShowSaveDialog}
+                            onSave={(filename, format) =>
+                                saveDiagramToFile(filename, format, sessionId)
+                            }
+                            defaultFilename={`diagram-${new Date()
+                                .toISOString()
+                                .slice(0, 10)}`}
+                        />
+
+                        <ButtonWithTooltip
+                            type="button"
+                            variant="ghost"
+                            size="sm"
                             onClick={triggerFileInput}
                             disabled={isDisabled}
-                        title="Upload image"
+                            tooltipContent="Upload image"
+                            className="h-8 w-8 p-0 text-muted-foreground hover:text-foreground"
                         >
                             <ImageIcon className="h-4 w-4" />
-                    </Button>
+                        </ButtonWithTooltip>
 
                         <input
                             type="file"
@@ -255,26 +451,30 @@ export function ChatInput({
                             multiple
                             disabled={isDisabled}
                         />
-                </div>
+
+                        <div className="w-px h-5 bg-border mx-1" />
 
                         <Button
                             type="submit"
                             disabled={isDisabled || !input.trim()}
-                    className="transition-opacity"
+                            size="sm"
+                            className="h-8 px-4 rounded-xl font-medium shadow-sm"
                             aria-label={
-                        isDisabled
-                            ? "Sending message..."
-                            : "Send message"
+                                isDisabled ? "Sending..." : "Send message"
                             }
                         >
                             {isDisabled ? (
-                        <Loader2 className="mr-2 h-4 w-4 animate-spin" />
+                                <Loader2 className="h-4 w-4 animate-spin" />
                             ) : (
-                        <Send className="mr-2 h-4 w-4" />
-                    )}
+                                <>
+                                    <Send className="h-4 w-4 mr-1.5" />
                                     Send
+                                </>
+                            )}
                         </Button>
                     </div>
+                </div>
+            </div>
         </form>
-    );
+    )
 }

components/chat-message-display.tsx

@@ -1,217 +1,742 @@
-"use client";
+"use client"
 
-import type React from "react";
-import { useRef, useEffect, useState, useCallback } from "react";
-import Image from "next/image";
-import { ScrollArea } from "@/components/ui/scroll-area";
-import ExamplePanel from "./chat-example-panel";
-import { UIMessage } from "ai";
-import { convertToLegalXml, replaceNodes } from "@/lib/utils";
+import type { UIMessage } from "ai"
 
-import { useDiagram } from "@/contexts/diagram-context";
+import {
+    Check,
+    ChevronDown,
+    ChevronUp,
+    Copy,
+    Cpu,
+    Minus,
+    Pencil,
+    Plus,
+    RotateCcw,
+    ThumbsDown,
+    ThumbsUp,
+    X,
+} from "lucide-react"
+import Image from "next/image"
+import { useCallback, useEffect, useRef, useState } from "react"
+import ReactMarkdown from "react-markdown"
+import { ScrollArea } from "@/components/ui/scroll-area"
+import {
+    convertToLegalXml,
+    replaceNodes,
+    validateMxCellStructure,
+} from "@/lib/utils"
+import ExamplePanel from "./chat-example-panel"
+import { CodeBlock } from "./code-block"
+
+interface EditPair {
+    search: string
+    replace: string
+}
+
+// Tool part interface for type safety
+interface ToolPartLike {
+    type: string
+    toolCallId: string
+    state?: string
+    input?: { xml?: string; edits?: EditPair[] } & Record<string, unknown>
+    output?: string
+}
+
+function EditDiffDisplay({ edits }: { edits: EditPair[] }) {
+    return (
+        <div className="space-y-3">
+            {edits.map((edit, index) => (
+                <div
+                    key={`${edit.search.slice(0, 50)}-${edit.replace.slice(0, 50)}-${index}`}
+                    className="rounded-lg border border-border/50 overflow-hidden bg-background/50"
+                >
+                    <div className="px-3 py-1.5 bg-muted/40 border-b border-border/30 flex items-center gap-2">
+                        <span className="text-xs font-medium text-muted-foreground">
+                            Change {index + 1}
+                        </span>
+                    </div>
+                    <div className="divide-y divide-border/30">
+                        {/* Search (old) */}
+                        <div className="px-3 py-2">
+                            <div className="flex items-center gap-1.5 mb-1.5">
+                                <Minus className="w-3 h-3 text-red-500" />
+                                <span className="text-[10px] font-medium text-red-600 uppercase tracking-wide">
+                                    Remove
+                                </span>
+                            </div>
+                            <pre className="text-[11px] font-mono text-red-700 bg-red-50 rounded px-2 py-1.5 overflow-x-auto whitespace-pre-wrap break-all">
+                                {edit.search}
+                            </pre>
+                        </div>
+                        {/* Replace (new) */}
+                        <div className="px-3 py-2">
+                            <div className="flex items-center gap-1.5 mb-1.5">
+                                <Plus className="w-3 h-3 text-green-500" />
+                                <span className="text-[10px] font-medium text-green-600 uppercase tracking-wide">
+                                    Add
+                                </span>
+                            </div>
+                            <pre className="text-[11px] font-mono text-green-700 bg-green-50 rounded px-2 py-1.5 overflow-x-auto whitespace-pre-wrap break-all">
+                                {edit.replace}
+                            </pre>
+                        </div>
+                    </div>
+                </div>
+            ))}
+        </div>
+    )
+}
+
+import { useDiagram } from "@/contexts/diagram-context"
+
+const getMessageTextContent = (message: UIMessage): string => {
+    if (!message.parts) return ""
+    return message.parts
+        .filter((part) => part.type === "text")
+        .map((part) => (part as { text: string }).text)
+        .join("\n")
+}
 
 interface ChatMessageDisplayProps {
-    messages: UIMessage[];
-    error?: Error | null;
-    setInput: (input: string) => void;
-    setFiles: (files: File[]) => void;
+    messages: UIMessage[]
+    setInput: (input: string) => void
+    setFiles: (files: File[]) => void
+    sessionId?: string
+    onRegenerate?: (messageIndex: number) => void
+    onEditMessage?: (messageIndex: number, newText: string) => void
 }
 
 export function ChatMessageDisplay({
     messages,
-    error,
     setInput,
     setFiles,
+    sessionId,
+    onRegenerate,
+    onEditMessage,
 }: ChatMessageDisplayProps) {
-    const { chartXML, loadDiagram: onDisplayChart } = useDiagram();
-    const messagesEndRef = useRef<HTMLDivElement>(null);
-    const previousXML = useRef<string>("");
-    const processedToolCalls = useRef<Set<string>>(new Set());
+    const { chartXML, loadDiagram: onDisplayChart } = useDiagram()
+    const messagesEndRef = useRef<HTMLDivElement>(null)
+    const previousXML = useRef<string>("")
+    const processedToolCalls = useRef<Set<string>>(new Set())
     const [expandedTools, setExpandedTools] = useState<Record<string, boolean>>(
-        {}
-    );
+        {},
+    )
+    const [copiedMessageId, setCopiedMessageId] = useState<string | null>(null)
+    const [copyFailedMessageId, setCopyFailedMessageId] = useState<
+        string | null
+    >(null)
+    const [feedback, setFeedback] = useState<Record<string, "good" | "bad">>({})
+    const [editingMessageId, setEditingMessageId] = useState<string | null>(
+        null,
+    )
+    const editTextareaRef = useRef<HTMLTextAreaElement>(null)
+    const [editText, setEditText] = useState<string>("")
+
+    const copyMessageToClipboard = async (messageId: string, text: string) => {
+        try {
+            await navigator.clipboard.writeText(text)
+            setCopiedMessageId(messageId)
+            setTimeout(() => setCopiedMessageId(null), 2000)
+        } catch (err) {
+            console.error("Failed to copy message:", err)
+            setCopyFailedMessageId(messageId)
+            setTimeout(() => setCopyFailedMessageId(null), 2000)
+        }
+    }
+
+    const submitFeedback = async (messageId: string, value: "good" | "bad") => {
+        // Toggle off if already selected
+        if (feedback[messageId] === value) {
+            setFeedback((prev) => {
+                const next = { ...prev }
+                delete next[messageId]
+                return next
+            })
+            return
+        }
+
+        setFeedback((prev) => ({ ...prev, [messageId]: value }))
+
+        try {
+            await fetch("/api/log-feedback", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({
+                    messageId,
+                    feedback: value,
+                    sessionId,
+                }),
+            })
+        } catch (error) {
+            console.warn("Failed to log feedback:", error)
+        }
+    }
+
     const handleDisplayChart = useCallback(
         (xml: string) => {
-            const currentXml = xml || "";
-            const convertedXml = convertToLegalXml(currentXml);
+            const currentXml = xml || ""
+            const convertedXml = convertToLegalXml(currentXml)
             if (convertedXml !== previousXML.current) {
-                previousXML.current = convertedXml;
-                const replacedXML = replaceNodes(chartXML, convertedXml);
-                onDisplayChart(replacedXML);
+                const replacedXML = replaceNodes(chartXML, convertedXml)
+
+                const validationError = validateMxCellStructure(replacedXML)
+                if (!validationError) {
+                    previousXML.current = convertedXml
+                    onDisplayChart(replacedXML)
+                } else {
+                    console.log(
+                        "[ChatMessageDisplay] XML validation failed:",
+                        validationError,
+                    )
+                }
             }
         },
-        [chartXML, onDisplayChart]
-    );
+        [chartXML, onDisplayChart],
+    )
 
     useEffect(() => {
         if (messagesEndRef.current) {
-            messagesEndRef.current.scrollIntoView({ behavior: "smooth" });
+            messagesEndRef.current.scrollIntoView({ behavior: "smooth" })
         }
-    }, [messages]);
+    }, [messages])
+
+    useEffect(() => {
+        if (editingMessageId && editTextareaRef.current) {
+            editTextareaRef.current.focus()
+        }
+    }, [editingMessageId])
 
-    // Handle tool invocations and update diagram when needed
     useEffect(() => {
         messages.forEach((message) => {
             if (message.parts) {
-                message.parts.forEach((part: any) => {
+                message.parts.forEach((part) => {
                     if (part.type?.startsWith("tool-")) {
-                        const { toolCallId, state } = part;
+                        const toolPart = part as ToolPartLike
+                        const { toolCallId, state, input } = toolPart
 
-                        // Auto-collapse args when diagrams are generated
                         if (state === "output-available") {
                             setExpandedTools((prev) => ({
                                 ...prev,
                                 [toolCallId]: false,
-                            }));
+                            }))
                         }
 
-                        // Handle diagram updates for display_diagram tool
                         if (
                             part.type === "tool-display_diagram" &&
-                            part.input?.xml
+                            input?.xml
                         ) {
-                            // For streaming input, always update to show streaming
+                            const xml = input.xml as string
                             if (
                                 state === "input-streaming" ||
                                 state === "input-available"
                             ) {
-                                handleDisplayChart(part.input.xml);
-                            }
-                            // For completed calls, only update if not processed yet
-                            else if (
+                                handleDisplayChart(xml)
+                            } else if (
                                 state === "output-available" &&
                                 !processedToolCalls.current.has(toolCallId)
                             ) {
-                                handleDisplayChart(part.input.xml);
-                                processedToolCalls.current.add(toolCallId);
+                                handleDisplayChart(xml)
+                                processedToolCalls.current.add(toolCallId)
                             }
                         }
                     }
-                });
+                })
             }
-        });
-    }, [messages, handleDisplayChart]);
+        })
+    }, [messages, handleDisplayChart])
 
-    const renderToolPart = (part: any) => {
-        const callId = part.toolCallId;
-        const { state, input, output } = part;
-        const isExpanded = expandedTools[callId] ?? true;
-        const toolName = part.type?.replace("tool-", "");
+    const renderToolPart = (part: ToolPartLike) => {
+        const callId = part.toolCallId
+        const { state, input, output } = part
+        const isExpanded = expandedTools[callId] ?? true
+        const toolName = part.type?.replace("tool-", "")
 
         const toggleExpanded = () => {
             setExpandedTools((prev) => ({
                 ...prev,
                 [callId]: !isExpanded,
-            }));
-        };
+            }))
+        }
+
+        const getToolDisplayName = (name: string) => {
+            switch (name) {
+                case "display_diagram":
+                    return "Generate Diagram"
+                case "edit_diagram":
+                    return "Edit Diagram"
+                default:
+                    return name
+            }
+        }
 
         return (
             <div
                 key={callId}
-                className="p-4 my-2 text-gray-500 border border-gray-300 rounded"
+                className="my-3 rounded-xl border border-border/60 bg-muted/30 overflow-hidden"
             >
-                <div className="flex flex-col gap-2">
-                    <div className="flex items-center justify-between">
-                        <div className="text-xs">Tool: {toolName}</div>
+                <div className="flex items-center justify-between px-4 py-3 bg-muted/50">
+                    <div className="flex items-center gap-2">
+                        <div className="w-6 h-6 rounded-md bg-primary/10 flex items-center justify-center">
+                            <Cpu className="w-3.5 h-3.5 text-primary" />
+                        </div>
+                        <span className="text-sm font-medium text-foreground/80">
+                            {getToolDisplayName(toolName)}
+                        </span>
+                    </div>
+                    <div className="flex items-center gap-2">
+                        {state === "input-streaming" && (
+                            <div className="h-4 w-4 border-2 border-primary border-t-transparent rounded-full animate-spin" />
+                        )}
+                        {state === "output-available" && (
+                            <span className="text-xs font-medium text-green-600 bg-green-50 px-2 py-0.5 rounded-full">
+                                Complete
+                            </span>
+                        )}
+                        {state === "output-error" && (
+                            <span className="text-xs font-medium text-red-600 bg-red-50 px-2 py-0.5 rounded-full">
+                                Error
+                            </span>
+                        )}
                         {input && Object.keys(input).length > 0 && (
                             <button
+                                type="button"
                                 onClick={toggleExpanded}
-                                className="text-xs text-gray-500 hover:text-gray-700"
+                                className="p-1 rounded hover:bg-muted transition-colors"
                             >
-                                {isExpanded ? "Hide Args" : "Show Args"}
+                                {isExpanded ? (
+                                    <ChevronUp className="w-4 h-4 text-muted-foreground" />
+                                ) : (
+                                    <ChevronDown className="w-4 h-4 text-muted-foreground" />
+                                )}
                             </button>
                         )}
                     </div>
+                </div>
                 {input && isExpanded && (
-                        <div className="mt-1 font-mono text-xs overflow-hidden">
-                            {typeof input === "object" &&
-                                Object.keys(input).length > 0 &&
-                                `Input: ${JSON.stringify(input, null, 2)}`}
-                        </div>
-                    )}
-                    <div className="mt-2 text-sm">
-                        {state === "input-streaming" ? (
-                            <div className="h-4 w-4 border-2 border-primary border-t-transparent rounded-full animate-spin" />
-                        ) : state === "output-available" ? (
-                            <div className="text-green-600">
-                                {output || (toolName === "display_diagram"
-                                    ? "Diagram generated"
-                                    : toolName === "edit_diagram"
-                                    ? "Diagram edited"
-                                    : "Tool executed")}
-                            </div>
-                        ) : state === "output-error" ? (
-                            <div className="text-red-600">
-                                {output || (toolName === "display_diagram"
-                                    ? "Error generating diagram"
-                                    : toolName === "edit_diagram"
-                                    ? "Error editing diagram"
-                                    : "Tool error")}
-                            </div>
+                    <div className="px-4 py-3 border-t border-border/40 bg-muted/20">
+                        {typeof input === "object" && input.xml ? (
+                            <CodeBlock code={input.xml} language="xml" />
+                        ) : typeof input === "object" &&
+                          input.edits &&
+                          Array.isArray(input.edits) ? (
+                            <EditDiffDisplay edits={input.edits} />
+                        ) : typeof input === "object" &&
+                          Object.keys(input).length > 0 ? (
+                            <CodeBlock
+                                code={JSON.stringify(input, null, 2)}
+                                language="json"
+                            />
                         ) : null}
                     </div>
+                )}
+                {output && state === "output-error" && (
+                    <div className="px-4 py-3 border-t border-border/40 text-sm text-red-600">
+                        {output}
                     </div>
+                )}
             </div>
-        );
-    };
+        )
+    }
 
     return (
-        <ScrollArea className="h-full pr-4">
+        <ScrollArea className="h-full w-full scrollbar-thin">
             {messages.length === 0 ? (
                 <ExamplePanel setInput={setInput} setFiles={setFiles} />
             ) : (
-                messages.map((message) => (
+                <div className="py-4 px-4 space-y-4">
+                    {messages.map((message, messageIndex) => {
+                        const userMessageText =
+                            message.role === "user"
+                                ? getMessageTextContent(message)
+                                : ""
+                        const isLastAssistantMessage =
+                            message.role === "assistant" &&
+                            (messageIndex === messages.length - 1 ||
+                                messages
+                                    .slice(messageIndex + 1)
+                                    .every((m) => m.role !== "assistant"))
+                        const isLastUserMessage =
+                            message.role === "user" &&
+                            (messageIndex === messages.length - 1 ||
+                                messages
+                                    .slice(messageIndex + 1)
+                                    .every((m) => m.role !== "user"))
+                        const isEditing = editingMessageId === message.id
+                        return (
                             <div
                                 key={message.id}
-                        className={`mb-4 ${
-                            message.role === "user" ? "text-right" : "text-left"
-                        }`}
+                                className={`flex w-full ${message.role === "user" ? "justify-end" : "justify-start"} animate-message-in`}
+                                style={{
+                                    animationDelay: `${messageIndex * 50}ms`,
+                                }}
                             >
+                                {message.role === "user" &&
+                                    userMessageText &&
+                                    !isEditing && (
+                                        <div className="flex items-center gap-1 self-center mr-2">
+                                            {/* Edit button - only on last user message */}
+                                            {onEditMessage &&
+                                                isLastUserMessage && (
+                                                    <button
+                                                        type="button"
+                                                        onClick={() => {
+                                                            setEditingMessageId(
+                                                                message.id,
+                                                            )
+                                                            setEditText(
+                                                                userMessageText,
+                                                            )
+                                                        }}
+                                                        className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-muted-foreground hover:bg-muted transition-colors"
+                                                        title="Edit message"
+                                                    >
+                                                        <Pencil className="h-3.5 w-3.5" />
+                                                    </button>
+                                                )}
+                                            <button
+                                                type="button"
+                                                onClick={() =>
+                                                    copyMessageToClipboard(
+                                                        message.id,
+                                                        userMessageText,
+                                                    )
+                                                }
+                                                className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-muted-foreground hover:bg-muted transition-colors"
+                                                title={
+                                                    copiedMessageId ===
+                                                    message.id
+                                                        ? "Copied!"
+                                                        : copyFailedMessageId ===
+                                                            message.id
+                                                          ? "Failed to copy"
+                                                          : "Copy message"
+                                                }
+                                            >
+                                                {copiedMessageId ===
+                                                message.id ? (
+                                                    <Check className="h-3.5 w-3.5 text-green-500" />
+                                                ) : copyFailedMessageId ===
+                                                  message.id ? (
+                                                    <X className="h-3.5 w-3.5 text-red-500" />
+                                                ) : (
+                                                    <Copy className="h-3.5 w-3.5" />
+                                                )}
+                                            </button>
+                                        </div>
+                                    )}
+                                <div className="max-w-[85%] min-w-0">
+                                    {/* Edit mode for user messages */}
+                                    {isEditing && message.role === "user" ? (
+                                        <div className="flex flex-col gap-2">
+                                            <textarea
+                                                ref={editTextareaRef}
+                                                value={editText}
+                                                onChange={(e) =>
+                                                    setEditText(e.target.value)
+                                                }
+                                                className="w-full min-w-[300px] px-4 py-3 text-sm rounded-2xl border border-primary bg-background text-foreground resize-none focus:outline-none focus:ring-2 focus:ring-primary"
+                                                rows={Math.min(
+                                                    editText.split("\n")
+                                                        .length + 1,
+                                                    6,
+                                                )}
+                                                onKeyDown={(e) => {
+                                                    if (e.key === "Escape") {
+                                                        setEditingMessageId(
+                                                            null,
+                                                        )
+                                                        setEditText("")
+                                                    } else if (
+                                                        e.key === "Enter" &&
+                                                        (e.metaKey || e.ctrlKey)
+                                                    ) {
+                                                        e.preventDefault()
+                                                        if (
+                                                            editText.trim() &&
+                                                            onEditMessage
+                                                        ) {
+                                                            onEditMessage(
+                                                                messageIndex,
+                                                                editText.trim(),
+                                                            )
+                                                            setEditingMessageId(
+                                                                null,
+                                                            )
+                                                            setEditText("")
+                                                        }
+                                                    }
+                                                }}
+                                            />
+                                            <div className="flex justify-end gap-2">
+                                                <button
+                                                    type="button"
+                                                    onClick={() => {
+                                                        setEditingMessageId(
+                                                            null,
+                                                        )
+                                                        setEditText("")
+                                                    }}
+                                                    className="px-3 py-1.5 text-xs rounded-lg bg-muted hover:bg-muted/80 transition-colors"
+                                                >
+                                                    Cancel
+                                                </button>
+                                                <button
+                                                    type="button"
+                                                    onClick={() => {
+                                                        if (
+                                                            editText.trim() &&
+                                                            onEditMessage
+                                                        ) {
+                                                            onEditMessage(
+                                                                messageIndex,
+                                                                editText.trim(),
+                                                            )
+                                                            setEditingMessageId(
+                                                                null,
+                                                            )
+                                                            setEditText("")
+                                                        }
+                                                    }}
+                                                    disabled={!editText.trim()}
+                                                    className="px-3 py-1.5 text-xs rounded-lg bg-primary text-primary-foreground hover:bg-primary/90 disabled:opacity-50 transition-colors"
+                                                >
+                                                    Save & Submit
+                                                </button>
+                                            </div>
+                                        </div>
+                                    ) : (
+                                        /* Text content in bubble */
+                                        message.parts?.some(
+                                            (part) =>
+                                                part.type === "text" ||
+                                                part.type === "file",
+                                        ) && (
                                             <div
-                            className={`inline-block px-4 py-2 whitespace-pre-wrap text-sm rounded-lg max-w-[85%] break-words ${
+                                                className={`px-4 py-3 text-sm leading-relaxed ${
                                                     message.role === "user"
-                                    ? "bg-primary text-primary-foreground"
-                                    : "bg-muted text-muted-foreground"
-                            }`}
+                                                        ? "bg-primary text-primary-foreground rounded-2xl rounded-br-md shadow-sm"
+                                                        : message.role ===
+                                                            "system"
+                                                          ? "bg-destructive/10 text-destructive border border-destructive/20 rounded-2xl rounded-bl-md"
+                                                          : "bg-muted/60 text-foreground rounded-2xl rounded-bl-md"
+                                                } ${message.role === "user" && isLastUserMessage && onEditMessage ? "cursor-pointer hover:opacity-90 transition-opacity" : ""}`}
+                                                role={
+                                                    message.role === "user" &&
+                                                    isLastUserMessage &&
+                                                    onEditMessage
+                                                        ? "button"
+                                                        : undefined
+                                                }
+                                                tabIndex={
+                                                    message.role === "user" &&
+                                                    isLastUserMessage &&
+                                                    onEditMessage
+                                                        ? 0
+                                                        : undefined
+                                                }
+                                                onClick={() => {
+                                                    if (
+                                                        message.role ===
+                                                            "user" &&
+                                                        isLastUserMessage &&
+                                                        onEditMessage
+                                                    ) {
+                                                        setEditingMessageId(
+                                                            message.id,
+                                                        )
+                                                        setEditText(
+                                                            userMessageText,
+                                                        )
+                                                    }
+                                                }}
+                                                onKeyDown={(e) => {
+                                                    if (
+                                                        (e.key === "Enter" ||
+                                                            e.key === " ") &&
+                                                        message.role ===
+                                                            "user" &&
+                                                        isLastUserMessage &&
+                                                        onEditMessage
+                                                    ) {
+                                                        e.preventDefault()
+                                                        setEditingMessageId(
+                                                            message.id,
+                                                        )
+                                                        setEditText(
+                                                            userMessageText,
+                                                        )
+                                                    }
+                                                }}
+                                                title={
+                                                    message.role === "user" &&
+                                                    isLastUserMessage &&
+                                                    onEditMessage
+                                                        ? "Click to edit"
+                                                        : undefined
+                                                }
                                             >
-                            {message.parts?.map((part: any, index: number) => {
+                                                {message.parts?.map(
+                                                    (part, index) => {
                                                         switch (part.type) {
                                                             case "text":
                                                                 return (
-                                            <div key={index}>{part.text}</div>
-                                        );
+                                                                    <div
+                                                                        key={`${message.id}-text-${index}`}
+                                                                        className={`prose prose-sm max-w-none break-words [&>*:first-child]:mt-0 [&>*:last-child]:mb-0 ${
+                                                                            message.role ===
+                                                                            "user"
+                                                                                ? "[&_*]:!text-primary-foreground prose-code:bg-white/20"
+                                                                                : "dark:prose-invert"
+                                                                        }`}
+                                                                    >
+                                                                        <ReactMarkdown>
+                                                                            {
+                                                                                part.text
+                                                                            }
+                                                                        </ReactMarkdown>
+                                                                    </div>
+                                                                )
                                                             case "file":
                                                                 return (
-                                            <div key={index} className="mt-2">
+                                                                    <div
+                                                                        key={`${message.id}-file-${part.url}`}
+                                                                        className="mt-2"
+                                                                    >
                                                                         <Image
-                                                    src={part.url}
-                                                    width={200}
-                                                    height={200}
+                                                                            src={
+                                                                                part.url
+                                                                            }
+                                                                            width={
+                                                                                200
+                                                                            }
+                                                                            height={
+                                                                                200
+                                                                            }
                                                                             alt={`Uploaded diagram or image for AI analysis`}
-                                                    className="rounded-md border"
+                                                                            className="rounded-lg border border-white/20"
                                                                             style={{
-                                                        objectFit: "contain",
+                                                                                objectFit:
+                                                                                    "contain",
                                                                             }}
                                                                         />
                                                                     </div>
-                                        );
+                                                                )
                                                             default:
-                                        if (part.type?.startsWith("tool-")) {
-                                            return renderToolPart(part);
+                                                                return null
                                                         }
-                                        return null;
-                                }
-                            })}
-                        </div>
-                    </div>
-                ))
+                                                    },
                                                 )}
-            {error && (
-                <div className="text-red-500 text-sm mt-2">
-                    Error: {error.message}
+                                            </div>
+                                        )
+                                    )}
+                                    {/* Tool calls outside bubble */}
+                                    {message.parts?.map((part) => {
+                                        if (part.type?.startsWith("tool-")) {
+                                            return renderToolPart(
+                                                part as ToolPartLike,
+                                            )
+                                        }
+                                        return null
+                                    })}
+                                    {/* Action buttons for assistant messages */}
+                                    {message.role === "assistant" && (
+                                        <div className="flex items-center gap-1 mt-2">
+                                            {/* Copy button */}
+                                            <button
+                                                type="button"
+                                                onClick={() =>
+                                                    copyMessageToClipboard(
+                                                        message.id,
+                                                        getMessageTextContent(
+                                                            message,
+                                                        ),
+                                                    )
+                                                }
+                                                className={`p-1.5 rounded-lg transition-colors ${
+                                                    copiedMessageId ===
+                                                    message.id
+                                                        ? "text-green-600 bg-green-100"
+                                                        : "text-muted-foreground/60 hover:text-foreground hover:bg-muted"
+                                                }`}
+                                                title={
+                                                    copiedMessageId ===
+                                                    message.id
+                                                        ? "Copied!"
+                                                        : "Copy response"
+                                                }
+                                            >
+                                                {copiedMessageId ===
+                                                message.id ? (
+                                                    <Check className="h-3.5 w-3.5" />
+                                                ) : (
+                                                    <Copy className="h-3.5 w-3.5" />
+                                                )}
+                                            </button>
+                                            {/* Regenerate button - only on last assistant message */}
+                                            {onRegenerate &&
+                                                isLastAssistantMessage && (
+                                                    <button
+                                                        type="button"
+                                                        onClick={() =>
+                                                            onRegenerate(
+                                                                messageIndex,
+                                                            )
+                                                        }
+                                                        className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-foreground hover:bg-muted transition-colors"
+                                                        title="Regenerate response"
+                                                    >
+                                                        <RotateCcw className="h-3.5 w-3.5" />
+                                                    </button>
+                                                )}
+                                            {/* Divider */}
+                                            <div className="w-px h-4 bg-border mx-1" />
+                                            {/* Thumbs up */}
+                                            <button
+                                                type="button"
+                                                onClick={() =>
+                                                    submitFeedback(
+                                                        message.id,
+                                                        "good",
+                                                    )
+                                                }
+                                                className={`p-1.5 rounded-lg transition-colors ${
+                                                    feedback[message.id] ===
+                                                    "good"
+                                                        ? "text-green-600 bg-green-100"
+                                                        : "text-muted-foreground/60 hover:text-green-600 hover:bg-green-50"
+                                                }`}
+                                                title="Good response"
+                                            >
+                                                <ThumbsUp className="h-3.5 w-3.5" />
+                                            </button>
+                                            {/* Thumbs down */}
+                                            <button
+                                                type="button"
+                                                onClick={() =>
+                                                    submitFeedback(
+                                                        message.id,
+                                                        "bad",
+                                                    )
+                                                }
+                                                className={`p-1.5 rounded-lg transition-colors ${
+                                                    feedback[message.id] ===
+                                                    "bad"
+                                                        ? "text-red-600 bg-red-100"
+                                                        : "text-muted-foreground/60 hover:text-red-600 hover:bg-red-50"
+                                                }`}
+                                                title="Bad response"
+                                            >
+                                                <ThumbsDown className="h-3.5 w-3.5" />
+                                            </button>
+                                        </div>
+                                    )}
+                                </div>
+                            </div>
+                        )
+                    })}
                 </div>
             )}
             <div ref={messagesEndRef} />
         </ScrollArea>
-    );
+    )
 }

components/chat-panel.tsx

@@ -1,71 +1,108 @@
-"use client";
-
-import type React from "react";
-import { useRef, useEffect, useState } from "react";
-import { FaGithub } from "react-icons/fa";
-import { PanelRightClose, PanelRightOpen } from "lucide-react";
-import Link from "next/link";
+"use client"
 
+import { useChat } from "@ai-sdk/react"
+import { DefaultChatTransport } from "ai"
 import {
-    Card,
-    CardContent,
-    CardFooter,
-    CardHeader,
-    CardTitle,
-} from "@/components/ui/card";
-import { useChat } from "@ai-sdk/react";
-import { DefaultChatTransport } from "ai";
-import { ChatInput } from "@/components/chat-input";
-import { ChatMessageDisplay } from "./chat-message-display";
-import { useDiagram } from "@/contexts/diagram-context";
-import { replaceNodes, formatXML } from "@/lib/utils";
-import { ButtonWithTooltip } from "@/components/button-with-tooltip";
+    CheckCircle,
+    PanelRightClose,
+    PanelRightOpen,
+    Settings,
+} from "lucide-react"
+import Image from "next/image"
+import Link from "next/link"
+import type React from "react"
+import { useEffect, useRef, useState } from "react"
+import { flushSync } from "react-dom"
+import { FaGithub } from "react-icons/fa"
+import { Toaster } from "sonner"
+import { ButtonWithTooltip } from "@/components/button-with-tooltip"
+import { ChatInput } from "@/components/chat-input"
+import {
+    SettingsDialog,
+    STORAGE_ACCESS_CODE_KEY,
+} from "@/components/settings-dialog"
+import { useDiagram } from "@/contexts/diagram-context"
+import { formatXML, validateMxCellStructure } from "@/lib/utils"
+import { ChatMessageDisplay } from "./chat-message-display"
 
 interface ChatPanelProps {
-    isVisible: boolean;
-    onToggleVisibility: () => void;
+    isVisible: boolean
+    onToggleVisibility: () => void
+    drawioUi: "min" | "sketch"
+    onToggleDrawioUi: () => void
+    isMobile?: boolean
 }
 
-export default function ChatPanel({ isVisible, onToggleVisibility }: ChatPanelProps) {
+export default function ChatPanel({
+    isVisible,
+    onToggleVisibility,
+    drawioUi,
+    onToggleDrawioUi,
+    isMobile = false,
+}: ChatPanelProps) {
     const {
         loadDiagram: onDisplayChart,
         handleExport: onExport,
+        handleExportWithoutHistory,
         resolverRef,
         chartXML,
         clearDiagram,
-    } = useDiagram();
+    } = useDiagram()
 
-    const onFetchChart = () => {
+    const onFetchChart = (saveToHistory = true) => {
         return Promise.race([
             new Promise<string>((resolve) => {
                 if (resolverRef && "current" in resolverRef) {
-                    resolverRef.current = resolve;
+                    resolverRef.current = resolve
+                }
+                if (saveToHistory) {
+                    onExport()
+                } else {
+                    handleExportWithoutHistory()
                 }
-                onExport();
             }),
             new Promise<string>((_, reject) =>
-                setTimeout(() => reject(new Error("Chart export timed out after 10 seconds")), 10000)
+                setTimeout(
+                    () =>
+                        reject(
+                            new Error(
+                                "Chart export timed out after 10 seconds",
+                            ),
+                        ),
+                    10000,
+                ),
+            ),
+        ])
+    }
+
+    const [files, setFiles] = useState<File[]>([])
+    const [showHistory, setShowHistory] = useState(false)
+    const [showSettingsDialog, setShowSettingsDialog] = useState(false)
+    const [accessCodeRequired, setAccessCodeRequired] = useState(false)
+    const [input, setInput] = useState("")
+
+    // Check if access code is required on mount
+    useEffect(() => {
+        fetch("/api/config")
+            .then((res) => res.json())
+            .then((data) => setAccessCodeRequired(data.accessCodeRequired))
+            .catch(() => setAccessCodeRequired(false))
+    }, [])
+
+    // Generate a unique session ID for Langfuse tracing
+    const [sessionId, setSessionId] = useState(
+        () => `session-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`,
     )
-        ]);
-    };
-    // Add a step counter to track updates
 
-    // Add state for file attachments
-    const [files, setFiles] = useState<File[]>([]);
-    // Add state for showing the history dialog
-    const [showHistory, setShowHistory] = useState(false);
+    // Store XML snapshots for each user message (keyed by message index)
+    const xmlSnapshotsRef = useRef<Map<number, string>>(new Map())
 
-    // Convert File[] to FileList for experimental_attachments
-    const createFileList = (files: File[]): FileList => {
-        const dt = new DataTransfer();
-        files.forEach((file) => dt.items.add(file));
-        return dt.files;
-    };
+    // Ref to track latest chartXML for use in callbacks (avoids stale closure)
+    const chartXMLRef = useRef(chartXML)
+    useEffect(() => {
+        chartXMLRef.current = chartXML
+    }, [chartXML])
 
-    // Add state for input management
-    const [input, setInput] = useState("");
-
-    // Remove the currentXmlRef and related useEffect
     const { messages, sendMessage, addToolResult, status, error, setMessages } =
         useChat({
             transport: new DefaultChatTransport({
@@ -73,40 +110,72 @@ export default function ChatPanel({ isVisible, onToggleVisibility }: ChatPanelPr
             }),
             async onToolCall({ toolCall }) {
                 if (toolCall.toolName === "display_diagram") {
-                    // Diagram is handled streamingly in the ChatMessageDisplay component
+                    const { xml } = toolCall.input as { xml: string }
+
+                    const validationError = validateMxCellStructure(xml)
+
+                    if (validationError) {
+                        addToolResult({
+                            tool: "display_diagram",
+                            toolCallId: toolCall.toolCallId,
+                            output: validationError,
+                        })
+                    } else {
                         addToolResult({
                             tool: "display_diagram",
                             toolCallId: toolCall.toolCallId,
                             output: "Successfully displayed the diagram.",
-                    });
+                        })
+                    }
                 } else if (toolCall.toolName === "edit_diagram") {
                     const { edits } = toolCall.input as {
-                        edits: Array<{ search: string; replace: string }>;
-                    };
+                        edits: Array<{ search: string; replace: string }>
+                    }
 
-                    let currentXml = '';
+                    let currentXml = ""
                     try {
-                        // Fetch current chart XML
-                        currentXml = await onFetchChart();
+                        console.log("[edit_diagram] Starting...")
+                        // Use chartXML from ref directly - more reliable than export
+                        // especially on Vercel where DrawIO iframe may have latency issues
+                        // Using ref to avoid stale closure in callback
+                        const cachedXML = chartXMLRef.current
+                        if (cachedXML) {
+                            currentXml = cachedXML
+                            console.log(
+                                "[edit_diagram] Using cached chartXML, length:",
+                                currentXml.length,
+                            )
+                        } else {
+                            // Fallback to export only if no cached XML
+                            console.log(
+                                "[edit_diagram] No cached XML, fetching from DrawIO...",
+                            )
+                            currentXml = await onFetchChart(false)
+                            console.log(
+                                "[edit_diagram] Got XML from export, length:",
+                                currentXml.length,
+                            )
+                        }
 
-                        // Apply edits using the utility function
-                        const { replaceXMLParts } = await import("@/lib/utils");
-                        const editedXml = replaceXMLParts(currentXml, edits);
+                        const { replaceXMLParts } = await import("@/lib/utils")
+                        const editedXml = replaceXMLParts(currentXml, edits)
 
-                        // Load the edited diagram
-                        onDisplayChart(editedXml);
+                        onDisplayChart(editedXml)
 
                         addToolResult({
                             tool: "edit_diagram",
                             toolCallId: toolCall.toolCallId,
                             output: `Successfully applied ${edits.length} edit(s) to the diagram.`,
-                        });
+                        })
+                        console.log("[edit_diagram] Success")
                     } catch (error) {
-                        console.error("Edit diagram failed:", error);
+                        console.error("[edit_diagram] Failed:", error)
 
-                        const errorMessage = error instanceof Error ? error.message : String(error);
+                        const errorMessage =
+                            error instanceof Error
+                                ? error.message
+                                : String(error)
 
-                        // Provide detailed error with current diagram XML
                         addToolResult({
                             tool: "edit_diagram",
                             toolCallId: toolCall.toolCallId,
@@ -114,169 +183,394 @@ export default function ChatPanel({ isVisible, onToggleVisibility }: ChatPanelPr
 
 Current diagram XML:
 \`\`\`xml
-${currentXml}
+${currentXml || "No XML available"}
 \`\`\`
 
 Please retry with an adjusted search pattern or use display_diagram if retries are exhausted.`,
-                        });
+                        })
                     }
                 }
             },
             onError: (error) => {
-                console.error("Chat error:", error);
+                // Silence access code error in console since it's handled by UI
+                if (!error.message.includes("Invalid or missing access code")) {
+                    console.error("Chat error:", error)
+                }
+
+                // Add system message for error so it can be cleared
+                setMessages((currentMessages) => {
+                    const errorMessage = {
+                        id: `error-${Date.now()}`,
+                        role: "system" as const,
+                        content: error.message,
+                        parts: [{ type: "text" as const, text: error.message }],
+                    }
+                    return [...currentMessages, errorMessage]
+                })
+
+                if (error.message.includes("Invalid or missing access code")) {
+                    // Show settings button and open dialog to help user fix it
+                    setAccessCodeRequired(true)
+                    setShowSettingsDialog(true)
+                }
             },
-        });
-    const messagesEndRef = useRef<HTMLDivElement>(null);
-    // Scroll to bottom when messages change
+        })
+
+    const messagesEndRef = useRef<HTMLDivElement>(null)
+
     useEffect(() => {
         if (messagesEndRef.current) {
-            messagesEndRef.current.scrollIntoView({ behavior: "smooth" });
+            messagesEndRef.current.scrollIntoView({ behavior: "smooth" })
         }
-    }, [messages]);
-
-    // Debug: Log status changes
-    useEffect(() => {
-        console.log('[ChatPanel] Status changed to:', status);
-    }, [status]);
+    }, [messages])
 
     const onFormSubmit = async (e: React.FormEvent<HTMLFormElement>) => {
-        e.preventDefault();
-        const isProcessing = status === "streaming" || status === "submitted";
+        e.preventDefault()
+        const isProcessing = status === "streaming" || status === "submitted"
         if (input.trim() && !isProcessing) {
             try {
-                // Fetch chart data before sending message
-                let chartXml = await onFetchChart();
+                let chartXml = await onFetchChart()
+                chartXml = formatXML(chartXml)
 
-                // Format the XML to ensure consistency
-                chartXml = formatXML(chartXml);
+                // Update ref directly to avoid race condition with React's async state update
+                // This ensures edit_diagram has the correct XML before AI responds
+                chartXMLRef.current = chartXml
 
-                // Create message parts
-                const parts: any[] = [{ type: "text", text: input }];
+                const parts: any[] = [{ type: "text", text: input }]
 
-                // Add file parts if files exist
                 if (files.length > 0) {
                     for (const file of files) {
-                        const reader = new FileReader();
+                        const reader = new FileReader()
                         const dataUrl = await new Promise<string>((resolve) => {
                             reader.onload = () =>
-                                resolve(reader.result as string);
-                            reader.readAsDataURL(file);
-                        });
+                                resolve(reader.result as string)
+                            reader.readAsDataURL(file)
+                        })
 
                         parts.push({
                             type: "file",
                             url: dataUrl,
                             mediaType: file.type,
-                        });
+                        })
                     }
                 }
 
+                // Save XML snapshot for this message (will be at index = current messages.length)
+                const messageIndex = messages.length
+                xmlSnapshotsRef.current.set(messageIndex, chartXml)
+
+                const accessCode =
+                    localStorage.getItem(STORAGE_ACCESS_CODE_KEY) || ""
                 sendMessage(
                     { parts },
                     {
                         body: {
                             xml: chartXml,
+                            sessionId,
                         },
-                    }
-                );
+                        headers: {
+                            "x-access-code": accessCode,
+                        },
+                    },
+                )
 
-                // Clear input and files after submission
-                setInput("");
-                setFiles([]);
+                setInput("")
+                setFiles([])
             } catch (error) {
-                console.error("Error fetching chart data:", error);
+                console.error("Error fetching chart data:", error)
+            }
         }
     }
-    };
 
-    // Handle input change
     const handleInputChange = (
-        e: React.ChangeEvent<HTMLInputElement | HTMLTextAreaElement>
+        e: React.ChangeEvent<HTMLInputElement | HTMLTextAreaElement>,
     ) => {
-        setInput(e.target.value);
-    };
+        setInput(e.target.value)
+    }
 
-    // Helper function to handle file changes
     const handleFileChange = (newFiles: File[]) => {
-        setFiles(newFiles);
-    };
+        setFiles(newFiles)
+    }
 
-    // Collapsed view when chat is hidden
-    if (!isVisible) {
+    const handleRegenerate = async (messageIndex: number) => {
+        const isProcessing = status === "streaming" || status === "submitted"
+        if (isProcessing) return
+
+        // Find the user message before this assistant message
+        let userMessageIndex = messageIndex - 1
+        while (
+            userMessageIndex >= 0 &&
+            messages[userMessageIndex].role !== "user"
+        ) {
+            userMessageIndex--
+        }
+
+        if (userMessageIndex < 0) return
+
+        const userMessage = messages[userMessageIndex]
+        const userParts = userMessage.parts
+
+        // Get the text from the user message
+        const textPart = userParts?.find((p: any) => p.type === "text")
+        if (!textPart) return
+
+        // Get the saved XML snapshot for this user message
+        const savedXml = xmlSnapshotsRef.current.get(userMessageIndex)
+        if (!savedXml) {
+            console.error(
+                "No saved XML snapshot for message index:",
+                userMessageIndex,
+            )
+            return
+        }
+
+        // Restore the diagram to the saved state
+        onDisplayChart(savedXml)
+
+        // Update ref directly to ensure edit_diagram has the correct XML
+        chartXMLRef.current = savedXml
+
+        // Clean up snapshots for messages after the user message (they will be removed)
+        for (const key of xmlSnapshotsRef.current.keys()) {
+            if (key > userMessageIndex) {
+                xmlSnapshotsRef.current.delete(key)
+            }
+        }
+
+        // Remove the user message AND assistant message onwards (sendMessage will re-add the user message)
+        // Use flushSync to ensure state update is processed synchronously before sending
+        const newMessages = messages.slice(0, userMessageIndex)
+        flushSync(() => {
+            setMessages(newMessages)
+        })
+
+        // Now send the message after state is guaranteed to be updated
+        sendMessage(
+            { parts: userParts },
+            {
+                body: {
+                    xml: savedXml,
+                    sessionId,
+                },
+            },
+        )
+    }
+
+    const handleEditMessage = async (messageIndex: number, newText: string) => {
+        const isProcessing = status === "streaming" || status === "submitted"
+        if (isProcessing) return
+
+        const message = messages[messageIndex]
+        if (!message || message.role !== "user") return
+
+        // Get the saved XML snapshot for this user message
+        const savedXml = xmlSnapshotsRef.current.get(messageIndex)
+        if (!savedXml) {
+            console.error(
+                "No saved XML snapshot for message index:",
+                messageIndex,
+            )
+            return
+        }
+
+        // Restore the diagram to the saved state
+        onDisplayChart(savedXml)
+
+        // Update ref directly to ensure edit_diagram has the correct XML
+        chartXMLRef.current = savedXml
+
+        // Clean up snapshots for messages after the user message (they will be removed)
+        for (const key of xmlSnapshotsRef.current.keys()) {
+            if (key > messageIndex) {
+                xmlSnapshotsRef.current.delete(key)
+            }
+        }
+
+        // Create new parts with updated text
+        const newParts = message.parts?.map((part: any) => {
+            if (part.type === "text") {
+                return { ...part, text: newText }
+            }
+            return part
+        }) || [{ type: "text", text: newText }]
+
+        // Remove the user message AND assistant message onwards (sendMessage will re-add the user message)
+        // Use flushSync to ensure state update is processed synchronously before sending
+        const newMessages = messages.slice(0, messageIndex)
+        flushSync(() => {
+            setMessages(newMessages)
+        })
+
+        // Now send the edited message after state is guaranteed to be updated
+        sendMessage(
+            { parts: newParts },
+            {
+                body: {
+                    xml: savedXml,
+                    sessionId,
+                },
+            },
+        )
+    }
+
+    // Collapsed view (desktop only)
+    if (!isVisible && !isMobile) {
         return (
-            <Card className="h-full flex flex-col rounded-none py-0 gap-0 items-center justify-start pt-4">
+            <div className="h-full flex flex-col items-center pt-4 bg-card border border-border/30 rounded-xl">
                 <ButtonWithTooltip
                     tooltipContent="Show chat panel (Ctrl+B)"
                     variant="ghost"
                     size="icon"
                     onClick={onToggleVisibility}
+                    className="hover:bg-accent transition-colors"
                 >
-                    <PanelRightOpen className="h-5 w-5" />
+                    <PanelRightOpen className="h-5 w-5 text-muted-foreground" />
                 </ButtonWithTooltip>
                 <div
-                    className="text-sm text-gray-500 mt-8"
-                    style={{ writingMode: 'vertical-rl', transform: 'rotate(180deg)' }}
+                    className="text-sm font-medium text-muted-foreground mt-8 tracking-wide"
+                    style={{
+                        writingMode: "vertical-rl",
+                        transform: "rotate(180deg)",
+                    }}
                 >
-                    Chat
+                    AI Chat
                 </div>
-            </Card>
-        );
+            </div>
+        )
     }
 
-    // Full view when chat is visible
+    // Full view
     return (
-        <Card className="h-full flex flex-col rounded-none py-0 gap-0">
-            <CardHeader className="p-4 flex flex-row justify-between items-center">
-                <div className="flex items-center gap-3">
-                    <CardTitle>Next-AI-Drawio</CardTitle>
-                    <Link href="/about" className="text-sm text-gray-600 hover:text-gray-900 transition-colors">
+        <div className="h-full flex flex-col bg-card shadow-soft animate-slide-in-right rounded-xl border border-border/30 relative">
+            <Toaster
+                position="bottom-center"
+                richColors
+                style={{ position: "absolute" }}
+            />
+            {/* Header */}
+            <header
+                className={`${isMobile ? "px-3 py-2" : "px-5 py-4"} border-b border-border/50`}
+            >
+                <div className="flex items-center justify-between">
+                    <div className="flex items-center gap-2">
+                        <div className="flex items-center gap-2">
+                            <Image
+                                src="/favicon.ico"
+                                alt="Next AI Drawio"
+                                width={isMobile ? 24 : 28}
+                                height={isMobile ? 24 : 28}
+                                className="rounded"
+                            />
+                            <h1
+                                className={`${isMobile ? "text-sm" : "text-base"} font-semibold tracking-tight whitespace-nowrap`}
+                            >
+                                Next AI Drawio
+                            </h1>
+                        </div>
+                        {!isMobile && (
+                            <Link
+                                href="/about"
+                                className="text-sm text-muted-foreground hover:text-foreground transition-colors ml-2"
+                            >
                                 About
                             </Link>
+                        )}
+                        {!isMobile && (
+                            <ButtonWithTooltip
+                                tooltipContent="Recent generation failures were caused by our AI provider's infrastructure issue, not the app code. After extensive debugging, I've switched providers and observed 6 hours of stability. If issues persist, please report on GitHub."
+                                variant="ghost"
+                                size="icon"
+                                className="h-6 w-6 text-green-500 hover:text-green-600"
+                            >
+                                <CheckCircle className="h-4 w-4" />
+                            </ButtonWithTooltip>
+                        )}
                     </div>
-                <div className="flex items-center gap-2">
+                    <div className="flex items-center gap-1">
+                        <a
+                            href="https://github.com/DayuanJiang/next-ai-draw-io"
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="p-2 rounded-lg text-muted-foreground hover:text-foreground hover:bg-accent transition-colors"
+                        >
+                            <FaGithub
+                                className={`${isMobile ? "w-4 h-4" : "w-5 h-5"}`}
+                            />
+                        </a>
+                        {accessCodeRequired && (
+                            <ButtonWithTooltip
+                                tooltipContent="Settings"
+                                variant="ghost"
+                                size="icon"
+                                onClick={() => setShowSettingsDialog(true)}
+                                className="hover:bg-accent"
+                            >
+                                <Settings
+                                    className={`${isMobile ? "h-4 w-4" : "h-5 w-5"} text-muted-foreground`}
+                                />
+                            </ButtonWithTooltip>
+                        )}
+                        {!isMobile && (
                             <ButtonWithTooltip
                                 tooltipContent="Hide chat panel (Ctrl+B)"
                                 variant="ghost"
                                 size="icon"
                                 onClick={onToggleVisibility}
+                                className="hover:bg-accent"
                             >
-                        <PanelRightClose className="h-5 w-5" />
+                                <PanelRightClose className="h-5 w-5 text-muted-foreground" />
                             </ButtonWithTooltip>
-                    <a
-                        href="https://github.com/DayuanJiang/next-ai-draw-io"
-                        target="_blank"
-                        rel="noopener noreferrer"
-                        className="text-gray-600 hover:text-gray-900 transition-colors"
-                    >
-                        <FaGithub className="w-6 h-6" />
-                    </a>
+                        )}
                     </div>
-            </CardHeader>
-            <CardContent className="flex-grow overflow-hidden px-2">
+                </div>
+            </header>
+
+            {/* Messages */}
+            <main className="flex-1 w-full overflow-hidden">
                 <ChatMessageDisplay
                     messages={messages}
-                    error={error}
                     setInput={setInput}
                     setFiles={handleFileChange}
+                    sessionId={sessionId}
+                    onRegenerate={handleRegenerate}
+                    onEditMessage={handleEditMessage}
                 />
-            </CardContent>
+            </main>
 
-            <CardFooter className="p-2">
+            {/* Input */}
+            <footer
+                className={`${isMobile ? "p-2" : "p-4"} border-t border-border/50 bg-card/50`}
+            >
                 <ChatInput
                     input={input}
                     status={status}
                     onSubmit={onFormSubmit}
                     onChange={handleInputChange}
                     onClearChat={() => {
-                        setMessages([]);
-                        clearDiagram();
+                        setMessages([])
+                        clearDiagram()
+                        setSessionId(
+                            `session-${Date.now()}-${Math.random()
+                                .toString(36)
+                                .slice(2, 9)}`,
+                        )
+                        xmlSnapshotsRef.current.clear()
                     }}
                     files={files}
                     onFileChange={handleFileChange}
                     showHistory={showHistory}
                     onToggleHistory={setShowHistory}
+                    sessionId={sessionId}
+                    error={error}
+                    drawioUi={drawioUi}
+                    onToggleDrawioUi={onToggleDrawioUi}
                 />
-            </CardFooter>
-        </Card>
-    );
+            </footer>
+
+            <SettingsDialog
+                open={showSettingsDialog}
+                onOpenChange={setShowSettingsDialog}
+            />
+        </div>
+    )
 }

components/code-block.tsx

@@ -0,0 +1,53 @@
+"use client"
+
+import { Highlight, themes } from "prism-react-renderer"
+
+interface CodeBlockProps {
+    code: string
+    language?: "xml" | "json"
+}
+
+export function CodeBlock({ code, language = "xml" }: CodeBlockProps) {
+    return (
+        <div className="overflow-hidden w-full">
+            <Highlight theme={themes.github} code={code} language={language}>
+                {({
+                    className: _className,
+                    style,
+                    tokens,
+                    getLineProps,
+                    getTokenProps,
+                }) => (
+                    <pre
+                        className="text-[11px] leading-relaxed overflow-x-auto overflow-y-auto max-h-48 scrollbar-thin break-all"
+                        style={{
+                            ...style,
+                            fontFamily:
+                                "var(--font-mono), ui-monospace, monospace",
+                            backgroundColor: "transparent",
+                            margin: 0,
+                            padding: 0,
+                            wordBreak: "break-all",
+                            whiteSpace: "pre-wrap",
+                        }}
+                    >
+                        {tokens.map((line, i) => (
+                            <div
+                                key={i}
+                                {...getLineProps({ line })}
+                                style={{ wordBreak: "break-all" }}
+                            >
+                                {line.map((token, key) => (
+                                    <span
+                                        key={key}
+                                        {...getTokenProps({ token })}
+                                    />
+                                ))}
+                            </div>
+                        ))}
+                    </pre>
+                )}
+            </Highlight>
+        </div>
+    )
+}

components/error-toast.tsx

@@ -0,0 +1,44 @@
+"use client"
+
+import type React from "react"
+
+interface ErrorToastProps {
+    message: React.ReactNode
+    onDismiss: () => void
+}
+
+export function ErrorToast({ message, onDismiss }: ErrorToastProps) {
+    const handleKeyDown = (e: React.KeyboardEvent) => {
+        if (e.key === "Enter" || e.key === " " || e.key === "Escape") {
+            e.preventDefault()
+            onDismiss()
+        }
+    }
+
+    return (
+        <div
+            role="alert"
+            aria-live="polite"
+            tabIndex={0}
+            onClick={onDismiss}
+            onKeyDown={handleKeyDown}
+            className="flex items-center gap-3 bg-card border border-border/50 px-4 py-3 rounded-xl shadow-sm cursor-pointer hover:bg-muted/50 focus:outline-none focus:ring-2 focus:ring-primary/50 transition-colors"
+        >
+            <div className="flex items-center justify-center w-8 h-8 rounded-full bg-destructive/10 flex-shrink-0">
+                <svg
+                    className="w-4 h-4 text-destructive"
+                    viewBox="0 0 20 20"
+                    fill="currentColor"
+                    aria-hidden="true"
+                >
+                    <path
+                        fillRule="evenodd"
+                        d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z"
+                        clipRule="evenodd"
+                    />
+                </svg>
+            </div>
+            <span className="text-sm text-foreground">{message}</span>
+        </div>
+    )
+}

components/file-preview-list.tsx

@@ -1,44 +1,84 @@
-"use client";
+"use client"
 
-import React, { useEffect, useState } from "react";
-import Image from "next/image";
-import { X } from "lucide-react";
+import { X } from "lucide-react"
+import Image from "next/image"
+import { useEffect, useRef, useState } from "react"
 
 interface FilePreviewListProps {
-    files: File[];
-    onRemoveFile: (fileToRemove: File) => void;
+    files: File[]
+    onRemoveFile: (fileToRemove: File) => void
 }
 
 export function FilePreviewList({ files, onRemoveFile }: FilePreviewListProps) {
-    const [selectedImage, setSelectedImage] = useState<string | null>(null);
+    const [selectedImage, setSelectedImage] = useState<string | null>(null)
+    const [imageUrls, setImageUrls] = useState<Map<File, string>>(new Map())
+    const imageUrlsRef = useRef<Map<File, string>>(new Map())
 
-    // Cleanup object URLs on unmount
+    // Create and cleanup object URLs when files change
     useEffect(() => {
-        const objectUrls = files
-            .filter((file) => file.type.startsWith("image/"))
-            .map((file) => URL.createObjectURL(file));
+        const currentUrls = imageUrlsRef.current
+        const newUrls = new Map<File, string>()
 
+        files.forEach((file) => {
+            if (file.type.startsWith("image/")) {
+                // Reuse existing URL if file is already tracked
+                const existingUrl = currentUrls.get(file)
+                if (existingUrl) {
+                    newUrls.set(file, existingUrl)
+                } else {
+                    newUrls.set(file, URL.createObjectURL(file))
+                }
+            }
+        })
+
+        // Revoke URLs for files that are no longer in the list
+        currentUrls.forEach((url, file) => {
+            if (!newUrls.has(file)) {
+                URL.revokeObjectURL(url)
+            }
+        })
+
+        imageUrlsRef.current = newUrls
+        setImageUrls(newUrls)
+    }, [files])
+
+    // Cleanup all URLs on unmount only
+    useEffect(() => {
         return () => {
-            objectUrls.forEach(URL.revokeObjectURL);
-        };
-    }, [files]);
+            imageUrlsRef.current.forEach((url) => {
+                URL.revokeObjectURL(url)
+            })
+        }
+    }, [])
 
-    if (files.length === 0) return null;
+    // Clear selected image if its URL was revoked
+    useEffect(() => {
+        if (
+            selectedImage &&
+            !Array.from(imageUrls.values()).includes(selectedImage)
+        ) {
+            setSelectedImage(null)
+        }
+    }, [imageUrls, selectedImage])
+
+    if (files.length === 0) return null
 
     return (
         <>
             <div className="flex flex-wrap gap-2 mt-2 p-2 bg-muted/50 rounded-md">
                 {files.map((file, index) => {
-                    const imageUrl = file.type.startsWith("image/") ? URL.createObjectURL(file) : null;
+                    const imageUrl = imageUrls.get(file) || null
                     return (
                         <div key={file.name + index} className="relative group">
                             <div
                                 className="w-20 h-20 border rounded-md overflow-hidden bg-muted cursor-pointer"
-                                onClick={() => imageUrl && setSelectedImage(imageUrl)}
+                                onClick={() =>
+                                    imageUrl && setSelectedImage(imageUrl)
+                                }
                             >
-                                {file.type.startsWith("image/") ? (
+                                {file.type.startsWith("image/") && imageUrl ? (
                                     <Image
-                                        src={imageUrl!}
+                                        src={imageUrl}
                                         alt={file.name}
                                         width={80}
                                         height={80}
@@ -59,7 +99,7 @@ export function FilePreviewList({ files, onRemoveFile }: FilePreviewListProps) {
                                 <X className="h-3 w-3" />
                             </button>
                         </div>
-                    );
+                    )
                 })}
             </div>
 
@@ -89,5 +129,5 @@ export function FilePreviewList({ files, onRemoveFile }: FilePreviewListProps) {
                 </div>
             )}
         </>
-    );
+    )
 }

components/history-dialog.tsx

@@ -1,5 +1,8 @@
-"use client";
+"use client"
 
+import Image from "next/image"
+import { useState } from "react"
+import { Button } from "@/components/ui/button"
 import {
     Dialog,
     DialogContent,
@@ -7,21 +10,32 @@ import {
     DialogFooter,
     DialogHeader,
     DialogTitle,
-} from "@/components/ui/dialog";
-import { Button } from "@/components/ui/button";
-import Image from "next/image";
-import { useDiagram } from "@/contexts/diagram-context";
+} from "@/components/ui/dialog"
+import { useDiagram } from "@/contexts/diagram-context"
 
 interface HistoryDialogProps {
-    showHistory: boolean;
-    onToggleHistory: (show: boolean) => void;
+    showHistory: boolean
+    onToggleHistory: (show: boolean) => void
 }
 
 export function HistoryDialog({
     showHistory,
     onToggleHistory,
 }: HistoryDialogProps) {
-    const { loadDiagram: onDisplayChart, diagramHistory } = useDiagram();
+    const { loadDiagram: onDisplayChart, diagramHistory } = useDiagram()
+    const [selectedIndex, setSelectedIndex] = useState<number | null>(null)
+
+    const handleClose = () => {
+        setSelectedIndex(null)
+        onToggleHistory(false)
+    }
+
+    const handleConfirmRestore = () => {
+        if (selectedIndex !== null) {
+            onDisplayChart(diagramHistory[selectedIndex].xml)
+            handleClose()
+        }
+    }
 
     return (
         <Dialog open={showHistory} onOpenChange={onToggleHistory}>
@@ -45,11 +59,12 @@ export function HistoryDialog({
                         {diagramHistory.map((item, index) => (
                             <div
                                 key={index}
-                                className="border rounded-md p-2 cursor-pointer hover:border-primary transition-colors"
-                                onClick={() => {
-                                    onDisplayChart(item.xml);
-                                    onToggleHistory(false);
-                                }}
+                                className={`border rounded-md p-2 cursor-pointer hover:border-primary transition-colors ${
+                                    selectedIndex === index
+                                        ? "border-primary ring-2 ring-primary"
+                                        : ""
+                                }`}
+                                onClick={() => setSelectedIndex(index)}
                             >
                                 <div className="aspect-video bg-white rounded overflow-hidden flex items-center justify-center">
                                     <Image
@@ -69,14 +84,28 @@ export function HistoryDialog({
                 )}
 
                 <DialogFooter>
+                    {selectedIndex !== null ? (
+                        <>
+                            <div className="flex-1 text-sm text-muted-foreground">
+                                Restore to Version {selectedIndex + 1}?
+                            </div>
                             <Button
                                 variant="outline"
-                        onClick={() => onToggleHistory(false)}
+                                onClick={() => setSelectedIndex(null)}
                             >
+                                Cancel
+                            </Button>
+                            <Button onClick={handleConfirmRestore}>
+                                Confirm
+                            </Button>
+                        </>
+                    ) : (
+                        <Button variant="outline" onClick={handleClose}>
                             Close
                         </Button>
+                    )}
                 </DialogFooter>
             </DialogContent>
         </Dialog>
-    );
+    )
 }

components/reset-warning-modal.tsx

@@ -1,6 +1,6 @@
-"use client";
+"use client"
 
-import { Button } from "@/components/ui/button";
+import { Button } from "@/components/ui/button"
 import {
     Dialog,
     DialogContent,
@@ -8,12 +8,12 @@ import {
     DialogFooter,
     DialogHeader,
     DialogTitle,
-} from "@/components/ui/dialog";
+} from "@/components/ui/dialog"
 
 interface ResetWarningModalProps {
-    open: boolean;
-    onOpenChange: (open: boolean) => void;
-    onClear: () => void;
+    open: boolean
+    onOpenChange: (open: boolean) => void
+    onClear: () => void
 }
 
 export function ResetWarningModal({
@@ -44,5 +44,5 @@ export function ResetWarningModal({
                 </DialogFooter>
             </DialogContent>
         </Dialog>
-    );
+    )
 }

components/save-dialog.tsx

@@ -0,0 +1,128 @@
+"use client"
+
+import { useEffect, useState } from "react"
+import { Button } from "@/components/ui/button"
+import {
+    Dialog,
+    DialogContent,
+    DialogFooter,
+    DialogHeader,
+    DialogTitle,
+} from "@/components/ui/dialog"
+import { Input } from "@/components/ui/input"
+import {
+    Select,
+    SelectContent,
+    SelectItem,
+    SelectTrigger,
+    SelectValue,
+} from "@/components/ui/select"
+
+export type ExportFormat = "drawio" | "png" | "svg"
+
+const FORMAT_OPTIONS: {
+    value: ExportFormat
+    label: string
+    extension: string
+}[] = [
+    { value: "drawio", label: "Draw.io XML", extension: ".drawio" },
+    { value: "png", label: "PNG Image", extension: ".png" },
+    { value: "svg", label: "SVG Image", extension: ".svg" },
+]
+
+interface SaveDialogProps {
+    open: boolean
+    onOpenChange: (open: boolean) => void
+    onSave: (filename: string, format: ExportFormat) => void
+    defaultFilename: string
+}
+
+export function SaveDialog({
+    open,
+    onOpenChange,
+    onSave,
+    defaultFilename,
+}: SaveDialogProps) {
+    const [filename, setFilename] = useState(defaultFilename)
+    const [format, setFormat] = useState<ExportFormat>("drawio")
+
+    useEffect(() => {
+        if (open) {
+            setFilename(defaultFilename)
+        }
+    }, [open, defaultFilename])
+
+    const handleSave = () => {
+        const finalFilename = filename.trim() || defaultFilename
+        onSave(finalFilename, format)
+        onOpenChange(false)
+    }
+
+    const handleKeyDown = (e: React.KeyboardEvent) => {
+        if (e.key === "Enter") {
+            e.preventDefault()
+            handleSave()
+        }
+    }
+
+    const currentFormat = FORMAT_OPTIONS.find((f) => f.value === format)
+
+    return (
+        <Dialog open={open} onOpenChange={onOpenChange}>
+            <DialogContent className="sm:max-w-md">
+                <DialogHeader>
+                    <DialogTitle>Save Diagram</DialogTitle>
+                </DialogHeader>
+                <div className="space-y-4">
+                    <div className="space-y-2">
+                        <label className="text-sm font-medium">Format</label>
+                        <Select
+                            value={format}
+                            onValueChange={(v) => setFormat(v as ExportFormat)}
+                        >
+                            <SelectTrigger>
+                                <SelectValue />
+                            </SelectTrigger>
+                            <SelectContent>
+                                {FORMAT_OPTIONS.map((opt) => (
+                                    <SelectItem
+                                        key={opt.value}
+                                        value={opt.value}
+                                    >
+                                        {opt.label}
+                                    </SelectItem>
+                                ))}
+                            </SelectContent>
+                        </Select>
+                    </div>
+                    <div className="space-y-2">
+                        <label className="text-sm font-medium">Filename</label>
+                        <div className="flex items-stretch">
+                            <Input
+                                value={filename}
+                                onChange={(e) => setFilename(e.target.value)}
+                                onKeyDown={handleKeyDown}
+                                placeholder="Enter filename"
+                                autoFocus
+                                onFocus={(e) => e.target.select()}
+                                className="rounded-r-none border-r-0 focus-visible:z-10"
+                            />
+                            <span className="inline-flex items-center px-3 rounded-r-md border border-l-0 border-input bg-muted text-sm text-muted-foreground font-mono">
+                                {currentFormat?.extension || ".drawio"}
+                            </span>
+                        </div>
+                    </div>
+                </div>
+                <DialogFooter>
+                    <Button
+                        variant="outline"
+                        onClick={() => onOpenChange(false)}
+                    >
+                        Cancel
+                    </Button>
+                    <Button onClick={handleSave}>Save</Button>
+                </DialogFooter>
+            </DialogContent>
+        </Dialog>
+    )
+}

components/settings-dialog.tsx

@@ -0,0 +1,84 @@
+"use client"
+
+import { useEffect, useState } from "react"
+import { Button } from "@/components/ui/button"
+import {
+    Dialog,
+    DialogContent,
+    DialogDescription,
+    DialogFooter,
+    DialogHeader,
+    DialogTitle,
+} from "@/components/ui/dialog"
+import { Input } from "@/components/ui/input"
+
+interface SettingsDialogProps {
+    open: boolean
+    onOpenChange: (open: boolean) => void
+}
+
+export const STORAGE_ACCESS_CODE_KEY = "next-ai-draw-io-access-code"
+
+export function SettingsDialog({ open, onOpenChange }: SettingsDialogProps) {
+    const [accessCode, setAccessCode] = useState("")
+
+    useEffect(() => {
+        if (open) {
+            const storedCode =
+                localStorage.getItem(STORAGE_ACCESS_CODE_KEY) || ""
+            setAccessCode(storedCode)
+        }
+    }, [open])
+
+    const handleSave = () => {
+        localStorage.setItem(STORAGE_ACCESS_CODE_KEY, accessCode.trim())
+        onOpenChange(false)
+    }
+
+    const handleKeyDown = (e: React.KeyboardEvent) => {
+        if (e.key === "Enter") {
+            e.preventDefault()
+            handleSave()
+        }
+    }
+
+    return (
+        <Dialog open={open} onOpenChange={onOpenChange}>
+            <DialogContent className="sm:max-w-md">
+                <DialogHeader>
+                    <DialogTitle>Settings</DialogTitle>
+                    <DialogDescription>
+                        Configure your access settings.
+                    </DialogDescription>
+                </DialogHeader>
+                <div className="space-y-4 py-2">
+                    <div className="space-y-2">
+                        <label className="text-sm font-medium leading-none peer-disabled:cursor-not-allowed peer-disabled:opacity-70">
+                            Access Code
+                        </label>
+                        <Input
+                            type="password"
+                            value={accessCode}
+                            onChange={(e) => setAccessCode(e.target.value)}
+                            onKeyDown={handleKeyDown}
+                            placeholder="Enter access code"
+                            autoComplete="off"
+                        />
+                        <p className="text-[0.8rem] text-muted-foreground">
+                            Required if the server has enabled access control.
+                        </p>
+                    </div>
+                </div>
+                <DialogFooter>
+                    <Button
+                        variant="outline"
+                        onClick={() => onOpenChange(false)}
+                    >
+                        Cancel
+                    </Button>
+                    <Button onClick={handleSave}>Save</Button>
+                </DialogFooter>
+            </DialogContent>
+        </Dialog>
+    )
+}

components/ui/button.tsx

@@ -10,7 +10,7 @@ const buttonVariants = cva(
     variants: {
       variant: {
         default:
-          "bg-primary text-primary-foreground shadow-xs hover:bg-primary/90",
+          "bg-primary text-primary-foreground shadow-xs hover:brightness-75",
         destructive:
           "bg-destructive text-white shadow-xs hover:bg-destructive/90 focus-visible:ring-destructive/20 dark:focus-visible:ring-destructive/40 dark:bg-destructive/60",
         outline:

components/ui/resizable.tsx

@@ -0,0 +1,56 @@
+"use client"
+
+import * as React from "react"
+import { GripVerticalIcon } from "lucide-react"
+import * as ResizablePrimitive from "react-resizable-panels"
+
+import { cn } from "@/lib/utils"
+
+function ResizablePanelGroup({
+  className,
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.PanelGroup>) {
+  return (
+    <ResizablePrimitive.PanelGroup
+      data-slot="resizable-panel-group"
+      className={cn(
+        "flex h-full w-full data-[panel-group-direction=vertical]:flex-col",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function ResizablePanel({
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.Panel>) {
+  return <ResizablePrimitive.Panel data-slot="resizable-panel" {...props} />
+}
+
+function ResizableHandle({
+  withHandle,
+  className,
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.PanelResizeHandle> & {
+  withHandle?: boolean
+}) {
+  return (
+    <ResizablePrimitive.PanelResizeHandle
+      data-slot="resizable-handle"
+      className={cn(
+        "bg-border focus-visible:ring-ring relative flex w-px items-center justify-center after:absolute after:inset-y-0 after:left-1/2 after:w-1 after:-translate-x-1/2 focus-visible:ring-1 focus-visible:ring-offset-1 focus-visible:outline-hidden data-[panel-group-direction=vertical]:h-px data-[panel-group-direction=vertical]:w-full data-[panel-group-direction=vertical]:after:left-0 data-[panel-group-direction=vertical]:after:h-1 data-[panel-group-direction=vertical]:after:w-full data-[panel-group-direction=vertical]:after:translate-x-0 data-[panel-group-direction=vertical]:after:-translate-y-1/2 [&[data-panel-group-direction=vertical]>div]:rotate-90",
+        className
+      )}
+      {...props}
+    >
+      {withHandle && (
+        <div className="bg-border z-10 flex h-4 w-3 items-center justify-center rounded-xs border">
+          <GripVerticalIcon className="size-2.5" />
+        </div>
+      )}
+    </ResizablePrimitive.PanelResizeHandle>
+  )
+}
+
+export { ResizablePanelGroup, ResizablePanel, ResizableHandle }

components/ui/scroll-area.tsx

@@ -18,7 +18,7 @@ function ScrollArea({
     >
       <ScrollAreaPrimitive.Viewport
         data-slot="scroll-area-viewport"
-        className="ring-ring/10 dark:ring-ring/20 dark:outline-ring/40 outline-ring/50 size-full rounded-[inherit] transition-[color,box-shadow] focus-visible:ring-4 focus-visible:outline-1"
+        className="ring-ring/10 dark:ring-ring/20 dark:outline-ring/40 outline-ring/50 size-full rounded-[inherit] transition-[color,box-shadow] focus-visible:ring-4 focus-visible:outline-1 !overflow-x-hidden"
       >
         {children}
       </ScrollAreaPrimitive.Viewport>

components/ui/select.tsx

@@ -0,0 +1,187 @@
+"use client"
+
+import * as React from "react"
+import * as SelectPrimitive from "@radix-ui/react-select"
+import { CheckIcon, ChevronDownIcon, ChevronUpIcon } from "lucide-react"
+
+import { cn } from "@/lib/utils"
+
+function Select({
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Root>) {
+  return <SelectPrimitive.Root data-slot="select" {...props} />
+}
+
+function SelectGroup({
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Group>) {
+  return <SelectPrimitive.Group data-slot="select-group" {...props} />
+}
+
+function SelectValue({
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Value>) {
+  return <SelectPrimitive.Value data-slot="select-value" {...props} />
+}
+
+function SelectTrigger({
+  className,
+  size = "default",
+  children,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Trigger> & {
+  size?: "sm" | "default"
+}) {
+  return (
+    <SelectPrimitive.Trigger
+      data-slot="select-trigger"
+      data-size={size}
+      className={cn(
+        "border-input data-[placeholder]:text-muted-foreground [&_svg:not([class*='text-'])]:text-muted-foreground focus-visible:border-ring focus-visible:ring-ring/50 aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive dark:bg-input/30 dark:hover:bg-input/50 flex w-fit items-center justify-between gap-2 rounded-md border bg-transparent px-3 py-2 text-sm whitespace-nowrap shadow-xs transition-[color,box-shadow] outline-none focus-visible:ring-[3px] disabled:cursor-not-allowed disabled:opacity-50 data-[size=default]:h-9 data-[size=sm]:h-8 *:data-[slot=select-value]:line-clamp-1 *:data-[slot=select-value]:flex *:data-[slot=select-value]:items-center *:data-[slot=select-value]:gap-2 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4",
+        className
+      )}
+      {...props}
+    >
+      {children}
+      <SelectPrimitive.Icon asChild>
+        <ChevronDownIcon className="size-4 opacity-50" />
+      </SelectPrimitive.Icon>
+    </SelectPrimitive.Trigger>
+  )
+}
+
+function SelectContent({
+  className,
+  children,
+  position = "popper",
+  align = "center",
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Content>) {
+  return (
+    <SelectPrimitive.Portal>
+      <SelectPrimitive.Content
+        data-slot="select-content"
+        className={cn(
+          "bg-popover text-popover-foreground data-[state=open]:animate-in data-[state=closed]:animate-out data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0 data-[state=closed]:zoom-out-95 data-[state=open]:zoom-in-95 data-[side=bottom]:slide-in-from-top-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2 relative z-50 max-h-(--radix-select-content-available-height) min-w-[8rem] origin-(--radix-select-content-transform-origin) overflow-x-hidden overflow-y-auto rounded-md border shadow-md",
+          position === "popper" &&
+            "data-[side=bottom]:translate-y-1 data-[side=left]:-translate-x-1 data-[side=right]:translate-x-1 data-[side=top]:-translate-y-1",
+          className
+        )}
+        position={position}
+        align={align}
+        {...props}
+      >
+        <SelectScrollUpButton />
+        <SelectPrimitive.Viewport
+          className={cn(
+            "p-1",
+            position === "popper" &&
+              "h-[var(--radix-select-trigger-height)] w-full min-w-[var(--radix-select-trigger-width)] scroll-my-1"
+          )}
+        >
+          {children}
+        </SelectPrimitive.Viewport>
+        <SelectScrollDownButton />
+      </SelectPrimitive.Content>
+    </SelectPrimitive.Portal>
+  )
+}
+
+function SelectLabel({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Label>) {
+  return (
+    <SelectPrimitive.Label
+      data-slot="select-label"
+      className={cn("text-muted-foreground px-2 py-1.5 text-xs", className)}
+      {...props}
+    />
+  )
+}
+
+function SelectItem({
+  className,
+  children,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Item>) {
+  return (
+    <SelectPrimitive.Item
+      data-slot="select-item"
+      className={cn(
+        "focus:bg-accent focus:text-accent-foreground [&_svg:not([class*='text-'])]:text-muted-foreground relative flex w-full cursor-default items-center gap-2 rounded-sm py-1.5 pr-8 pl-2 text-sm outline-hidden select-none data-[disabled]:pointer-events-none data-[disabled]:opacity-50 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4 *:[span]:last:flex *:[span]:last:items-center *:[span]:last:gap-2",
+        className
+      )}
+      {...props}
+    >
+      <span className="absolute right-2 flex size-3.5 items-center justify-center">
+        <SelectPrimitive.ItemIndicator>
+          <CheckIcon className="size-4" />
+        </SelectPrimitive.ItemIndicator>
+      </span>
+      <SelectPrimitive.ItemText>{children}</SelectPrimitive.ItemText>
+    </SelectPrimitive.Item>
+  )
+}
+
+function SelectSeparator({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Separator>) {
+  return (
+    <SelectPrimitive.Separator
+      data-slot="select-separator"
+      className={cn("bg-border pointer-events-none -mx-1 my-1 h-px", className)}
+      {...props}
+    />
+  )
+}
+
+function SelectScrollUpButton({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.ScrollUpButton>) {
+  return (
+    <SelectPrimitive.ScrollUpButton
+      data-slot="select-scroll-up-button"
+      className={cn(
+        "flex cursor-default items-center justify-center py-1",
+        className
+      )}
+      {...props}
+    >
+      <ChevronUpIcon className="size-4" />
+    </SelectPrimitive.ScrollUpButton>
+  )
+}
+
+function SelectScrollDownButton({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.ScrollDownButton>) {
+  return (
+    <SelectPrimitive.ScrollDownButton
+      data-slot="select-scroll-down-button"
+      className={cn(
+        "flex cursor-default items-center justify-center py-1",
+        className
+      )}
+      {...props}
+    >
+      <ChevronDownIcon className="size-4" />
+    </SelectPrimitive.ScrollDownButton>
+  )
+}
+
+export {
+  Select,
+  SelectContent,
+  SelectGroup,
+  SelectItem,
+  SelectLabel,
+  SelectScrollDownButton,
+  SelectScrollUpButton,
+  SelectSeparator,
+  SelectTrigger,
+  SelectValue,
+}

contexts/diagram-context.tsx

@@ -1,72 +1,210 @@
-"use client";
+"use client"
 
-import React, { createContext, useContext, useRef, useState } from "react";
-import type { DrawIoEmbedRef } from "react-drawio";
-import { extractDiagramXML } from "../lib/utils";
+import type React from "react"
+import { createContext, useContext, useRef, useState } from "react"
+import type { DrawIoEmbedRef } from "react-drawio"
+import type { ExportFormat } from "@/components/save-dialog"
+import { extractDiagramXML } from "../lib/utils"
 
 interface DiagramContextType {
-    chartXML: string;
-    latestSvg: string;
-    diagramHistory: { svg: string; xml: string }[];
-    loadDiagram: (chart: string) => void;
-    handleExport: () => void;
-    resolverRef: React.Ref<((value: string) => void) | null>;
-    drawioRef: React.Ref<DrawIoEmbedRef | null>;
-    handleDiagramExport: (data: any) => void;
-    clearDiagram: () => void;
+    chartXML: string
+    latestSvg: string
+    diagramHistory: { svg: string; xml: string }[]
+    loadDiagram: (chart: string) => void
+    handleExport: () => void
+    handleExportWithoutHistory: () => void
+    resolverRef: React.Ref<((value: string) => void) | null>
+    drawioRef: React.Ref<DrawIoEmbedRef | null>
+    handleDiagramExport: (data: any) => void
+    clearDiagram: () => void
+    saveDiagramToFile: (
+        filename: string,
+        format: ExportFormat,
+        sessionId?: string,
+    ) => void
 }
 
-const DiagramContext = createContext<DiagramContextType | undefined>(undefined);
+const DiagramContext = createContext<DiagramContextType | undefined>(undefined)
 
 export function DiagramProvider({ children }: { children: React.ReactNode }) {
-    const [chartXML, setChartXML] = useState<string>("");
-    const [latestSvg, setLatestSvg] = useState<string>("");
+    const [chartXML, setChartXML] = useState<string>("")
+    const [latestSvg, setLatestSvg] = useState<string>("")
     const [diagramHistory, setDiagramHistory] = useState<
         { svg: string; xml: string }[]
-    >([]);
-    const drawioRef = useRef<DrawIoEmbedRef | null>(null);
-    const resolverRef = useRef<((value: string) => void) | null>(null);
+    >([])
+    const drawioRef = useRef<DrawIoEmbedRef | null>(null)
+    const resolverRef = useRef<((value: string) => void) | null>(null)
+    // Track if we're expecting an export for history (user-initiated)
+    const expectHistoryExportRef = useRef<boolean>(false)
+    // Track if we're expecting an export for file save (stores raw export data)
+    const saveResolverRef = useRef<{
+        resolver: ((data: string) => void) | null
+        format: ExportFormat | null
+    }>({ resolver: null, format: null })
 
     const handleExport = () => {
         if (drawioRef.current) {
+            // Mark that this export should be saved to history
+            expectHistoryExportRef.current = true
             drawioRef.current.exportDiagram({
                 format: "xmlsvg",
-            });
+            })
+        }
+    }
+
+    const handleExportWithoutHistory = () => {
+        if (drawioRef.current) {
+            // Export without saving to history (for edit_diagram fetching current state)
+            drawioRef.current.exportDiagram({
+                format: "xmlsvg",
+            })
+        }
     }
-    };
 
     const loadDiagram = (chart: string) => {
         if (drawioRef.current) {
             drawioRef.current.load({
                 xml: chart,
-            });
+            })
+        }
     }
-    };
 
     const handleDiagramExport = (data: any) => {
-        const extractedXML = extractDiagramXML(data.data);
-        setChartXML(extractedXML);
-        setLatestSvg(data.data);
+        // Handle save to file if requested (process raw data before extraction)
+        if (saveResolverRef.current.resolver) {
+            const format = saveResolverRef.current.format
+            saveResolverRef.current.resolver(data.data)
+            saveResolverRef.current = { resolver: null, format: null }
+            // For non-xmlsvg formats, skip XML extraction as it will fail
+            // Only drawio (which uses xmlsvg internally) has the content attribute
+            if (format === "png" || format === "svg") {
+                return
+            }
+        }
+
+        const extractedXML = extractDiagramXML(data.data)
+        setChartXML(extractedXML)
+        setLatestSvg(data.data)
+
+        // Only add to history if this was a user-initiated export
+        if (expectHistoryExportRef.current) {
             setDiagramHistory((prev) => [
                 ...prev,
                 {
                     svg: data.data,
                     xml: extractedXML,
                 },
-        ]);
-        if (resolverRef.current) {
-            resolverRef.current(extractedXML);
-            resolverRef.current = null;
+            ])
+            expectHistoryExportRef.current = false
+        }
+
+        if (resolverRef.current) {
+            resolverRef.current(extractedXML)
+            resolverRef.current = null
+        }
     }
-    };
 
     const clearDiagram = () => {
-        const emptyDiagram = `<mxfile><diagram name="Page-1" id="page-1"><mxGraphModel><root><mxCell id="0"/><mxCell id="1" parent="0"/></root></mxGraphModel></diagram></mxfile>`;
-        loadDiagram(emptyDiagram);
-        setChartXML(emptyDiagram);
-        setLatestSvg("");
-        setDiagramHistory([]);
-    };
+        const emptyDiagram = `<mxfile><diagram name="Page-1" id="page-1"><mxGraphModel><root><mxCell id="0"/><mxCell id="1" parent="0"/></root></mxGraphModel></diagram></mxfile>`
+        loadDiagram(emptyDiagram)
+        setChartXML(emptyDiagram)
+        setLatestSvg("")
+        setDiagramHistory([])
+    }
+
+    const saveDiagramToFile = (
+        filename: string,
+        format: ExportFormat,
+        sessionId?: string,
+    ) => {
+        if (!drawioRef.current) {
+            console.warn("Draw.io editor not ready")
+            return
+        }
+
+        // Map format to draw.io export format
+        const drawioFormat = format === "drawio" ? "xmlsvg" : format
+
+        // Set up the resolver before triggering export
+        saveResolverRef.current = {
+            resolver: (exportData: string) => {
+                let fileContent: string | Blob
+                let mimeType: string
+                let extension: string
+
+                if (format === "drawio") {
+                    // Extract XML from SVG for .drawio format
+                    const xml = extractDiagramXML(exportData)
+                    let xmlContent = xml
+                    if (!xml.includes("<mxfile")) {
+                        xmlContent = `<mxfile><diagram name="Page-1" id="page-1">${xml}</diagram></mxfile>`
+                    }
+                    fileContent = xmlContent
+                    mimeType = "application/xml"
+                    extension = ".drawio"
+                } else if (format === "png") {
+                    // PNG data comes as base64 data URL
+                    fileContent = exportData
+                    mimeType = "image/png"
+                    extension = ".png"
+                } else {
+                    // SVG format
+                    fileContent = exportData
+                    mimeType = "image/svg+xml"
+                    extension = ".svg"
+                }
+
+                // Log save event to Langfuse (flags the trace)
+                logSaveToLangfuse(filename, format, sessionId)
+
+                // Handle download
+                let url: string
+                if (
+                    typeof fileContent === "string" &&
+                    fileContent.startsWith("data:")
+                ) {
+                    // Already a data URL (PNG)
+                    url = fileContent
+                } else {
+                    const blob = new Blob([fileContent], { type: mimeType })
+                    url = URL.createObjectURL(blob)
+                }
+
+                const a = document.createElement("a")
+                a.href = url
+                a.download = `${filename}${extension}`
+                document.body.appendChild(a)
+                a.click()
+                document.body.removeChild(a)
+
+                // Delay URL revocation to ensure download completes
+                if (!url.startsWith("data:")) {
+                    setTimeout(() => URL.revokeObjectURL(url), 100)
+                }
+            },
+            format,
+        }
+
+        // Export diagram - callback will be handled in handleDiagramExport
+        drawioRef.current.exportDiagram({ format: drawioFormat })
+    }
+
+    // Log save event to Langfuse (just flags the trace, doesn't send content)
+    const logSaveToLangfuse = async (
+        filename: string,
+        format: string,
+        sessionId?: string,
+    ) => {
+        try {
+            await fetch("/api/log-save", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({ filename, format, sessionId }),
+            })
+        } catch (error) {
+            console.warn("Failed to log save to Langfuse:", error)
+        }
+    }
 
     return (
         <DiagramContext.Provider
@@ -76,21 +214,23 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
                 diagramHistory,
                 loadDiagram,
                 handleExport,
+                handleExportWithoutHistory,
                 resolverRef,
                 drawioRef,
                 handleDiagramExport,
                 clearDiagram,
+                saveDiagramToFile,
             }}
         >
             {children}
         </DiagramContext.Provider>
-    );
+    )
 }
 
 export function useDiagram() {
-    const context = useContext(DiagramContext);
+    const context = useContext(DiagramContext)
     if (context === undefined) {
-        throw new Error("useDiagram must be used within a DiagramProvider");
+        throw new Error("useDiagram must be used within a DiagramProvider")
     }
-    return context;
+    return context
 }

docs/ai-providers.md

@@ -0,0 +1,141 @@
+# AI Provider Configuration
+
+This guide explains how to configure different AI model providers for next-ai-draw-io.
+
+## Quick Start
+
+1. Copy `.env.example` to `.env.local`
+2. Set your API key for your chosen provider
+3. Set `AI_MODEL` to your desired model
+4. Run `npm run dev`
+
+## Supported Providers
+
+### Google Gemini
+
+```bash
+GOOGLE_GENERATIVE_AI_API_KEY=your_api_key
+AI_MODEL=gemini-2.0-flash
+```
+
+Optional custom endpoint:
+
+```bash
+GOOGLE_BASE_URL=https://your-custom-endpoint
+```
+
+### OpenAI
+
+```bash
+OPENAI_API_KEY=your_api_key
+AI_MODEL=gpt-4o
+```
+
+Optional custom endpoint (for OpenAI-compatible services):
+
+```bash
+OPENAI_BASE_URL=https://your-custom-endpoint/v1
+```
+
+### Anthropic
+
+```bash
+ANTHROPIC_API_KEY=your_api_key
+AI_MODEL=claude-sonnet-4-5-20250514
+```
+
+Optional custom endpoint:
+
+```bash
+ANTHROPIC_BASE_URL=https://your-custom-endpoint
+```
+
+### DeepSeek
+
+```bash
+DEEPSEEK_API_KEY=your_api_key
+AI_MODEL=deepseek-chat
+```
+
+Optional custom endpoint:
+
+```bash
+DEEPSEEK_BASE_URL=https://your-custom-endpoint
+```
+
+### Azure OpenAI
+
+```bash
+AZURE_API_KEY=your_api_key
+AI_MODEL=your-deployment-name
+```
+
+Optional custom endpoint:
+
+```bash
+AZURE_BASE_URL=https://your-resource.openai.azure.com
+```
+
+### AWS Bedrock
+
+```bash
+AWS_REGION=us-west-2
+AWS_ACCESS_KEY_ID=your_access_key_id
+AWS_SECRET_ACCESS_KEY=your_secret_access_key
+AI_MODEL=anthropic.claude-sonnet-4-5-20250514-v1:0
+```
+
+Note: On AWS (Amplify, Lambda, EC2 with IAM role), credentials are automatically obtained from the IAM role.
+
+### OpenRouter
+
+```bash
+OPENROUTER_API_KEY=your_api_key
+AI_MODEL=anthropic/claude-sonnet-4
+```
+
+Optional custom endpoint:
+
+```bash
+OPENROUTER_BASE_URL=https://your-custom-endpoint
+```
+
+### Ollama (Local)
+
+```bash
+AI_PROVIDER=ollama
+AI_MODEL=llama3.2
+```
+
+Optional custom URL:
+
+```bash
+OLLAMA_BASE_URL=http://localhost:11434
+```
+
+## Auto-Detection
+
+If you only configure **one** provider's API key, the system will automatically detect and use that provider. No need to set `AI_PROVIDER`.
+
+If you configure **multiple** API keys, you must explicitly set `AI_PROVIDER`:
+
+```bash
+AI_PROVIDER=google  # or: openai, anthropic, deepseek, azure, bedrock, openrouter, ollama
+```
+
+## Model Capability Requirements
+
+This task requires exceptionally strong model capabilities, as it involves generating long-form text with strict formatting constraints (draw.io XML).
+
+**Recommended models**:
+
+-   Claude Sonnet 4.5 / Opus 4.5
+
+**Note on Ollama**: While Ollama is supported as a provider, it's generally not practical for this use case unless you're running high-capability models like DeepSeek R1 or Qwen3-235B locally.
+
+## Recommendations
+
+-   **Best experience**: Use models with vision support (GPT-4o, Claude, Gemini) for image-to-diagram features
+-   **Budget-friendly**: DeepSeek offers competitive pricing
+-   **Privacy**: Use Ollama for fully local, offline operation (requires powerful hardware)
+-   **Flexibility**: OpenRouter provides access to many models through a single API

env.example

@@ -1,6 +1,6 @@
 # AI Provider Configuration
 # AI_PROVIDER: Which provider to use
-# Options: bedrock, openai, anthropic, google, azure, ollama, openrouter
+# Options: bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek
 # Default: bedrock
 AI_PROVIDER=bedrock
 
@@ -20,16 +20,33 @@ AI_MODEL=global.anthropic.claude-sonnet-4-5-20250929-v1:0
 
 # Anthropic (Direct) Configuration
 # ANTHROPIC_API_KEY=sk-ant-...
+# ANTHROPIC_BASE_URL=https://your-custom-anthropic/v1
 
 # Google Generative AI Configuration
 # GOOGLE_GENERATIVE_AI_API_KEY=...
+# GOOGLE_BASE_URL=https://generativelanguage.googleapis.com/v1beta  # Optional: Custom endpoint
 
 # Azure OpenAI Configuration
 # AZURE_RESOURCE_NAME=your-resource-name
 # AZURE_API_KEY=...
+# AZURE_BASE_URL=https://your-resource.openai.azure.com  # Optional: Custom endpoint (overrides resourceName)
 
 # Ollama (Local) Configuration
 # OLLAMA_BASE_URL=http://localhost:11434/api  # Optional, defaults to localhost
 
 # OpenRouter Configuration
 # OPENROUTER_API_KEY=sk-or-v1-...
+# OPENROUTER_BASE_URL=https://openrouter.ai/api/v1  # Optional: Custom endpoint
+
+# DeepSeek Configuration
+# DEEPSEEK_API_KEY=sk-...
+# DEEPSEEK_BASE_URL=https://api.deepseek.com/v1  # Optional: Custom endpoint
+
+# Langfuse Observability (Optional)
+# Enable LLM tracing and analytics - https://langfuse.com
+# LANGFUSE_PUBLIC_KEY=pk-lf-...
+# LANGFUSE_SECRET_KEY=sk-lf-...
+# LANGFUSE_BASEURL=https://cloud.langfuse.com  # EU region, use https://us.cloud.langfuse.com for US
+
+# Access Control (Optional)
+# ACCESS_CODE_LIST=your-secret-code,another-code

instrumentation.ts

@@ -0,0 +1,39 @@
+import { LangfuseSpanProcessor } from "@langfuse/otel"
+import { NodeTracerProvider } from "@opentelemetry/sdk-trace-node"
+
+export function register() {
+    // Skip telemetry if Langfuse env vars are not configured
+    if (!process.env.LANGFUSE_PUBLIC_KEY || !process.env.LANGFUSE_SECRET_KEY) {
+        console.warn(
+            "[Langfuse] Environment variables not configured - telemetry disabled",
+        )
+        return
+    }
+
+    const langfuseSpanProcessor = new LangfuseSpanProcessor({
+        publicKey: process.env.LANGFUSE_PUBLIC_KEY,
+        secretKey: process.env.LANGFUSE_SECRET_KEY,
+        baseUrl: process.env.LANGFUSE_BASEURL,
+        // Filter out Next.js HTTP request spans so AI SDK spans become root traces
+        shouldExportSpan: ({ otelSpan }) => {
+            const spanName = otelSpan.name
+            // Skip Next.js HTTP infrastructure spans
+            if (
+                spanName.startsWith("POST /") ||
+                spanName.startsWith("GET /") ||
+                spanName.includes("BaseServer") ||
+                spanName.includes("handleRequest")
+            ) {
+                return false
+            }
+            return true
+        },
+    })
+
+    const tracerProvider = new NodeTracerProvider({
+        spanProcessors: [langfuseSpanProcessor],
+    })
+
+    // Register globally so AI SDK's telemetry also uses this processor
+    tracerProvider.register()
+}

lib/ai-providers.ts

@@ -1,54 +1,88 @@
-import { bedrock } from '@ai-sdk/amazon-bedrock';
-import { openai, createOpenAI } from '@ai-sdk/openai';
-import { anthropic } from '@ai-sdk/anthropic';
-import { google } from '@ai-sdk/google';
-import { azure } from '@ai-sdk/azure';
-import { ollama } from 'ollama-ai-provider-v2';
-import { createOpenRouter } from '@openrouter/ai-sdk-provider';
+import { createAmazonBedrock } from "@ai-sdk/amazon-bedrock"
+import { createAnthropic } from "@ai-sdk/anthropic"
+import { azure, createAzure } from "@ai-sdk/azure"
+import { createDeepSeek, deepseek } from "@ai-sdk/deepseek"
+import { createGoogleGenerativeAI, google } from "@ai-sdk/google"
+import { createOpenAI, openai } from "@ai-sdk/openai"
+import { fromNodeProviderChain } from "@aws-sdk/credential-providers"
+import { createOpenRouter } from "@openrouter/ai-sdk-provider"
+import { createOllama, ollama } from "ollama-ai-provider-v2"
 
 export type ProviderName =
-  | 'bedrock'
-  | 'openai'
-  | 'anthropic'
-  | 'google'
-  | 'azure'
-  | 'ollama'
-  | 'openrouter';
+    | "bedrock"
+    | "openai"
+    | "anthropic"
+    | "google"
+    | "azure"
+    | "ollama"
+    | "openrouter"
+    | "deepseek"
 
 interface ModelConfig {
-  model: any;
-  providerOptions?: any;
+    model: any
+    providerOptions?: any
+    headers?: Record<string, string>
+    modelId: string
 }
 
-// Anthropic beta headers for fine-grained tool streaming
-const ANTHROPIC_BETA_OPTIONS = {
-  anthropic: {
-    additionalModelRequestFields: {
-      anthropic_beta: ['fine-grained-tool-streaming-2025-05-14']
+// Bedrock provider options for Anthropic beta features
+const BEDROCK_ANTHROPIC_BETA = {
+    bedrock: {
+        anthropicBeta: ["fine-grained-tool-streaming-2025-05-14"],
+    },
+}
+
+// Direct Anthropic API headers for beta features
+const ANTHROPIC_BETA_HEADERS = {
+    "anthropic-beta": "fine-grained-tool-streaming-2025-05-14",
+}
+
+// Map of provider to required environment variable
+const PROVIDER_ENV_VARS: Record<ProviderName, string | null> = {
+    bedrock: null, // AWS SDK auto-uses IAM role on AWS, or env vars locally
+    openai: "OPENAI_API_KEY",
+    anthropic: "ANTHROPIC_API_KEY",
+    google: "GOOGLE_GENERATIVE_AI_API_KEY",
+    azure: "AZURE_API_KEY",
+    ollama: null, // No credentials needed for local Ollama
+    openrouter: "OPENROUTER_API_KEY",
+    deepseek: "DEEPSEEK_API_KEY",
+}
+
+/**
+ * Auto-detect provider based on available API keys
+ * Returns the provider if exactly one is configured, otherwise null
+ */
+function detectProvider(): ProviderName | null {
+    const configuredProviders: ProviderName[] = []
+
+    for (const [provider, envVar] of Object.entries(PROVIDER_ENV_VARS)) {
+        if (envVar === null) {
+            // Skip ollama - it doesn't require credentials
+            continue
+        }
+        if (process.env[envVar]) {
+            configuredProviders.push(provider as ProviderName)
         }
     }
-};
+
+    if (configuredProviders.length === 1) {
+        return configuredProviders[0]
+    }
+
+    return null
+}
 
 /**
  * Validate that required API keys are present for the selected provider
  */
 function validateProviderCredentials(provider: ProviderName): void {
-  const requiredEnvVars: Record<ProviderName, string | null> = {
-    bedrock: 'AWS_ACCESS_KEY_ID',
-    openai: 'OPENAI_API_KEY',
-    anthropic: 'ANTHROPIC_API_KEY',
-    google: 'GOOGLE_GENERATIVE_AI_API_KEY',
-    azure: 'AZURE_API_KEY',
-    ollama: null, // No credentials needed for local Ollama
-    openrouter: 'OPENROUTER_API_KEY',
-  };
-
-  const requiredVar = requiredEnvVars[provider];
+    const requiredVar = PROVIDER_ENV_VARS[provider]
     if (requiredVar && !process.env[requiredVar]) {
         throw new Error(
             `${requiredVar} environment variable is required for ${provider} provider. ` +
-      `Please set it in your .env.local file.`
-    );
+                `Please set it in your .env.local file.`,
+        )
     }
 }
 
@@ -56,7 +90,7 @@ function validateProviderCredentials(provider: ProviderName): void {
  * Get the AI model based on environment variables
  *
  * Environment variables:
- * - AI_PROVIDER: The provider to use (bedrock, openai, anthropic, google, azure, ollama, openrouter)
+ * - AI_PROVIDER: The provider to use (bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek)
  * - AI_MODEL: The model ID/name for the selected provider
  *
  * Provider-specific env vars:
@@ -68,82 +102,168 @@ function validateProviderCredentials(provider: ProviderName): void {
  * - AWS_REGION, AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY: AWS Bedrock credentials
  * - OLLAMA_BASE_URL: Ollama server URL (optional, defaults to http://localhost:11434)
  * - OPENROUTER_API_KEY: OpenRouter API key
+ * - DEEPSEEK_API_KEY: DeepSeek API key
+ * - DEEPSEEK_BASE_URL: DeepSeek endpoint (optional)
  */
 export function getAIModel(): ModelConfig {
-  const provider = (process.env.AI_PROVIDER || 'bedrock') as ProviderName;
-  const modelId = process.env.AI_MODEL;
+    const modelId = process.env.AI_MODEL
 
     if (!modelId) {
         throw new Error(
-      `AI_MODEL environment variable is required. Example: AI_MODEL=claude-sonnet-4-5`
-    );
+            `AI_MODEL environment variable is required. Example: AI_MODEL=claude-sonnet-4-5`,
+        )
+    }
+
+    // Determine provider: explicit config > auto-detect > error
+    let provider: ProviderName
+    if (process.env.AI_PROVIDER) {
+        provider = process.env.AI_PROVIDER as ProviderName
+    } else {
+        const detected = detectProvider()
+        if (detected) {
+            provider = detected
+            console.log(`[AI Provider] Auto-detected provider: ${provider}`)
+        } else {
+            // List configured providers for better error message
+            const configured = Object.entries(PROVIDER_ENV_VARS)
+                .filter(([, envVar]) => envVar && process.env[envVar as string])
+                .map(([p]) => p)
+
+            if (configured.length === 0) {
+                throw new Error(
+                    `No AI provider configured. Please set one of the following API keys in your .env.local file:\n` +
+                        `- DEEPSEEK_API_KEY for DeepSeek\n` +
+                        `- OPENAI_API_KEY for OpenAI\n` +
+                        `- ANTHROPIC_API_KEY for Anthropic\n` +
+                        `- GOOGLE_GENERATIVE_AI_API_KEY for Google\n` +
+                        `- AWS_ACCESS_KEY_ID for Bedrock\n` +
+                        `- OPENROUTER_API_KEY for OpenRouter\n` +
+                        `- AZURE_API_KEY for Azure\n` +
+                        `Or set AI_PROVIDER=ollama for local Ollama.`,
+                )
+            } else {
+                throw new Error(
+                    `Multiple AI providers configured (${configured.join(", ")}). ` +
+                        `Please set AI_PROVIDER to specify which one to use.`,
+                )
+            }
+        }
     }
 
     // Validate provider credentials
-  validateProviderCredentials(provider);
+    validateProviderCredentials(provider)
 
-  // Log initialization for debugging
-  console.log(`[AI Provider] Initializing ${provider} with model: ${modelId}`);
+    console.log(`[AI Provider] Initializing ${provider} with model: ${modelId}`)
 
-  let model: any;
-  let providerOptions: any = undefined;
+    let model: any
+    let providerOptions: any
+    let headers: Record<string, string> | undefined
 
     switch (provider) {
-    case 'bedrock':
-      model = bedrock(modelId);
-      // Add Anthropic beta headers if using Claude models via Bedrock
-      if (modelId.includes('anthropic.claude')) {
-        providerOptions = ANTHROPIC_BETA_OPTIONS;
+        case "bedrock": {
+            // Use credential provider chain for IAM role support (Amplify, Lambda, etc.)
+            // Falls back to env vars (AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY) for local dev
+            const bedrockProvider = createAmazonBedrock({
+                region: process.env.AWS_REGION || "us-west-2",
+                credentialProvider: fromNodeProviderChain(),
+            })
+            model = bedrockProvider(modelId)
+            // Add Anthropic beta options if using Claude models via Bedrock
+            if (modelId.includes("anthropic.claude")) {
+                providerOptions = BEDROCK_ANTHROPIC_BETA
+            }
+            break
         }
-      break;
 
-    case 'openai':
+        case "openai":
             if (process.env.OPENAI_BASE_URL) {
                 const customOpenAI = createOpenAI({
                     apiKey: process.env.OPENAI_API_KEY,
                     baseURL: process.env.OPENAI_BASE_URL,
-        });
-        model = customOpenAI.chat(modelId);
+                })
+                model = customOpenAI.chat(modelId)
             } else {
-        model = openai(modelId);
+                model = openai(modelId)
             }
-      break;
+            break
 
-    case 'anthropic':
-      model = anthropic(modelId);
+        case "anthropic": {
+            const customProvider = createAnthropic({
+                apiKey: process.env.ANTHROPIC_API_KEY,
+                baseURL:
+                    process.env.ANTHROPIC_BASE_URL ||
+                    "https://api.anthropic.com/v1",
+                headers: ANTHROPIC_BETA_HEADERS,
+            })
+            model = customProvider(modelId)
             // Add beta headers for fine-grained tool streaming
-      providerOptions = ANTHROPIC_BETA_OPTIONS;
-      break;
+            headers = ANTHROPIC_BETA_HEADERS
+            break
+        }
 
-    case 'google':
-      model = google(modelId);
-      break;
+        case "google":
+            if (process.env.GOOGLE_BASE_URL) {
+                const customGoogle = createGoogleGenerativeAI({
+                    apiKey: process.env.GOOGLE_GENERATIVE_AI_API_KEY,
+                    baseURL: process.env.GOOGLE_BASE_URL,
+                })
+                model = customGoogle(modelId)
+            } else {
+                model = google(modelId)
+            }
+            break
 
-    case 'azure':
-      model = azure(modelId);
-      break;
+        case "azure":
+            if (process.env.AZURE_BASE_URL) {
+                const customAzure = createAzure({
+                    apiKey: process.env.AZURE_API_KEY,
+                    baseURL: process.env.AZURE_BASE_URL,
+                })
+                model = customAzure(modelId)
+            } else {
+                model = azure(modelId)
+            }
+            break
 
-    case 'ollama':
-      model = ollama(modelId);
-      break;
+        case "ollama":
+            if (process.env.OLLAMA_BASE_URL) {
+                const customOllama = createOllama({
+                    baseURL: process.env.OLLAMA_BASE_URL,
+                })
+                model = customOllama(modelId)
+            } else {
+                model = ollama(modelId)
+            }
+            break
 
-    case 'openrouter':
+        case "openrouter": {
             const openrouter = createOpenRouter({
                 apiKey: process.env.OPENROUTER_API_KEY,
-      });
-      model = openrouter(modelId);
-      break;
+                ...(process.env.OPENROUTER_BASE_URL && {
+                    baseURL: process.env.OPENROUTER_BASE_URL,
+                }),
+            })
+            model = openrouter(modelId)
+            break
+        }
+
+        case "deepseek":
+            if (process.env.DEEPSEEK_BASE_URL) {
+                const customDeepSeek = createDeepSeek({
+                    apiKey: process.env.DEEPSEEK_API_KEY,
+                    baseURL: process.env.DEEPSEEK_BASE_URL,
+                })
+                model = customDeepSeek(modelId)
+            } else {
+                model = deepseek(modelId)
+            }
+            break
 
         default:
             throw new Error(
-        `Unknown AI provider: ${provider}. Supported providers: bedrock, openai, anthropic, google, azure, ollama, openrouter`
-      );
+                `Unknown AI provider: ${provider}. Supported providers: bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek`,
+            )
     }
 
-  // Log if provider options are being applied
-  if (providerOptions) {
-    console.log('[AI Provider] Applying provider-specific options');
-  }
-
-  return { model, providerOptions };
+    return { model, providerOptions, headers, modelId }
 }

lib/cached-responses.ts

@@ -0,0 +1,561 @@
+export interface CachedResponse {
+    promptText: string
+    hasImage: boolean
+    xml: string
+}
+
+export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
+    {
+        promptText:
+            "Give me a **animated connector** diagram of transformer's architecture",
+        hasImage: false,
+        xml: `<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+
+
+  <mxCell id="title" value="Transformer Architecture" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=20;fontStyle=1;" vertex="1" parent="1">
+    <mxGeometry x="300" y="20" width="250" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="input_embed" value="Input Embedding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
+    <mxGeometry x="80" y="480" width="120" height="40" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="pos_enc_left" value="Positional Encoding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
+    <mxGeometry x="80" y="420" width="120" height="40" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="encoder_box" value="ENCODER" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#e1d5e7;strokeColor=#9673a6;verticalAlign=top;fontSize=12;fontStyle=1;" vertex="1" parent="1">
+    <mxGeometry x="60" y="180" width="160" height="220" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="mha_enc" value="Multi-Head&#xa;Attention" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="80" y="330" width="120" height="50" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="add_norm1_enc" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="80" y="280" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="ff_enc" value="Feed Forward" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="80" y="240" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="add_norm2_enc" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="80" y="200" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="nx_enc" value="Nx" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=11;fontStyle=2;" vertex="1" parent="1">
+    <mxGeometry x="30" y="275" width="30" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="output_embed" value="Output Embedding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
+    <mxGeometry x="650" y="480" width="120" height="40" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="pos_enc_right" value="Positional Encoding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
+    <mxGeometry x="650" y="420" width="120" height="40" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="decoder_box" value="DECODER" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#ffe6cc;strokeColor=#d79b00;verticalAlign=top;fontSize=12;fontStyle=1;" vertex="1" parent="1">
+    <mxGeometry x="630" y="140" width="160" height="260" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="masked_mha_dec" value="Masked Multi-Head&#xa;Attention" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="650" y="340" width="120" height="50" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="add_norm1_dec" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="650" y="290" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="mha_dec" value="Multi-Head&#xa;Attention" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="650" y="240" width="120" height="40" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="add_norm2_dec" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="650" y="200" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="ff_dec" value="Feed Forward" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="650" y="160" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="add_norm3_dec" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
+    <mxGeometry x="650" y="120" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="nx_dec" value="Nx" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=11;fontStyle=2;" vertex="1" parent="1">
+    <mxGeometry x="790" y="255" width="30" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="linear" value="Linear" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;fontSize=11;" vertex="1" parent="1">
+    <mxGeometry x="650" y="80" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="softmax" value="Softmax" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;fontSize=11;" vertex="1" parent="1">
+    <mxGeometry x="650" y="40" width="120" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="output" value="Output Probabilities" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;fontStyle=1;" vertex="1" parent="1">
+    <mxGeometry x="640" y="0" width="140" height="30" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="conn1" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#6c8ebf;flowAnimation=1;" edge="1" parent="1" source="input_embed" target="pos_enc_left">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn2" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#6c8ebf;flowAnimation=1;" edge="1" parent="1" source="pos_enc_left" target="mha_enc">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn3" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#82b366;flowAnimation=1;" edge="1" parent="1" source="mha_enc" target="add_norm1_enc">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn4" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#d6b656;flowAnimation=1;" edge="1" parent="1" source="add_norm1_enc" target="ff_enc">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn5" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#82b366;flowAnimation=1;" edge="1" parent="1" source="ff_enc" target="add_norm2_enc">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="conn_cross" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=1;exitY=0.5;exitDx=0;exitDy=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=3;strokeColor=#9673a6;flowAnimation=1;dashed=1;" edge="1" parent="1" source="add_norm2_enc" target="mha_dec">
+    <mxGeometry relative="1" as="geometry">
+      <Array as="points">
+        <mxPoint x="400" y="215"/>
+        <mxPoint x="400" y="260"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+  <mxCell id="cross_label" value="K, V" style="edgeLabel;html=1;align=center;verticalAlign=middle;resizable=0;points=[];fontSize=10;fontStyle=1;fillColor=#ffffff;" vertex="1" connectable="0" parent="conn_cross">
+    <mxGeometry x="-0.1" y="1" relative="1" as="geometry">
+      <mxPoint x="10" y="-9" as="offset"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="conn6" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#d79b00;flowAnimation=1;" edge="1" parent="1" source="output_embed" target="pos_enc_right">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn7" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#d79b00;flowAnimation=1;" edge="1" parent="1" source="pos_enc_right" target="masked_mha_dec">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn8" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#82b366;flowAnimation=1;" edge="1" parent="1" source="masked_mha_dec" target="add_norm1_dec">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn9" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#d6b656;flowAnimation=1;" edge="1" parent="1" source="add_norm1_dec" target="mha_dec">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn10" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#82b366;flowAnimation=1;" edge="1" parent="1" source="mha_dec" target="add_norm2_dec">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn11" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#d6b656;flowAnimation=1;" edge="1" parent="1" source="add_norm2_dec" target="ff_dec">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn12" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#82b366;flowAnimation=1;" edge="1" parent="1" source="ff_dec" target="add_norm3_dec">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn13" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#b85450;flowAnimation=1;" edge="1" parent="1" source="add_norm3_dec" target="linear">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn14" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#b85450;flowAnimation=1;" edge="1" parent="1" source="linear" target="softmax">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="conn15" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#6c8ebf;flowAnimation=1;" edge="1" parent="1" source="softmax" target="output">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="res1_enc" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0;exitY=0.5;exitDx=0;exitDy=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="mha_enc" target="add_norm1_enc">
+    <mxGeometry relative="1" as="geometry">
+      <Array as="points">
+        <mxPoint x="50" y="355"/>
+        <mxPoint x="50" y="295"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+  <mxCell id="res2_enc" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0;exitY=0.5;exitDx=0;exitDy=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="ff_enc" target="add_norm2_enc">
+    <mxGeometry relative="1" as="geometry">
+      <Array as="points">
+        <mxPoint x="50" y="255"/>
+        <mxPoint x="50" y="215"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="res1_dec" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=1;exitY=0.5;exitDx=0;exitDy=0;entryX=1;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="masked_mha_dec" target="add_norm1_dec">
+    <mxGeometry relative="1" as="geometry">
+      <Array as="points">
+        <mxPoint x="800" y="365"/>
+        <mxPoint x="800" y="305"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+  <mxCell id="res2_dec" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=1;exitY=0.5;exitDx=0;exitDy=0;entryX=1;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="mha_dec" target="add_norm2_dec">
+    <mxGeometry relative="1" as="geometry">
+      <Array as="points">
+        <mxPoint x="800" y="260"/>
+        <mxPoint x="800" y="215"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+  <mxCell id="res3_dec" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=1;exitY=0.5;exitDx=0;exitDy=0;entryX=1;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="ff_dec" target="add_norm3_dec">
+    <mxGeometry relative="1" as="geometry">
+      <Array as="points">
+        <mxPoint x="800" y="175"/>
+        <mxPoint x="800" y="135"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="input_label" value="Inputs" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=12;fontStyle=1;" vertex="1" parent="1">
+    <mxGeometry x="110" y="530" width="60" height="20" as="geometry"/>
+  </mxCell>
+
+  <mxCell id="output_label" value="Outputs&#xa;(shifted right)" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=12;fontStyle=1;" vertex="1" parent="1">
+    <mxGeometry x="660" y="530" width="100" height="30" as="geometry"/>
+  </mxCell>
+</root>`,
+    },
+    {
+        promptText: "Replicate this in aws style",
+        hasImage: true,
+        xml: `<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+
+
+  <mxCell id="2" value="AWS" style="sketch=0;outlineConnect=0;gradientColor=none;html=1;whiteSpace=wrap;fontSize=12;fontStyle=0;container=1;pointerEvents=0;collapsible=0;recursiveResize=0;shape=mxgraph.aws4.group;grIcon=mxgraph.aws4.group_aws_cloud;strokeColor=#232F3E;fillColor=none;verticalAlign=top;align=left;spacingLeft=30;fontColor=#232F3E;dashed=0;rounded=1;arcSize=5;" vertex="1" parent="1">
+    <mxGeometry x="340" y="40" width="880" height="520" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="3" value="User" style="sketch=0;outlineConnect=0;fontColor=#232F3E;gradientColor=none;fillColor=#232F3D;strokeColor=none;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;pointerEvents=1;shape=mxgraph.aws4.user;rounded=1;" vertex="1" parent="1">
+    <mxGeometry x="80" y="240" width="78" height="78" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="4" value="EC2" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#ED7100;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.ec2;rounded=1;" vertex="1" parent="1">
+    <mxGeometry x="560" y="240" width="78" height="78" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="5" value="S3" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#7AA116;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.s3;rounded=1;" vertex="1" parent="1">
+    <mxGeometry x="960" y="120" width="78" height="78" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="6" value="bedrock" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#01A88D;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.bedrock;rounded=1;" vertex="1" parent="1">
+    <mxGeometry x="960" y="260" width="78" height="78" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="7" value="DynamoDB" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#C925D1;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.dynamodb;rounded=1;" vertex="1" parent="1">
+    <mxGeometry x="960" y="400" width="78" height="78" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="8" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.5;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="3" target="4">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="400" y="350" as="sourcePoint"/>
+      <mxPoint x="450" y="300" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="9" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.25;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="4" target="5">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="700" y="350" as="sourcePoint"/>
+      <mxPoint x="750" y="300" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="10" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.5;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="4" target="6">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="700" y="350" as="sourcePoint"/>
+      <mxPoint x="750" y="300" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="11" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.75;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="4" target="7">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="700" y="350" as="sourcePoint"/>
+      <mxPoint x="750" y="300" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+</root>`,
+    },
+    {
+        promptText: "Replicate this flowchart.",
+        hasImage: true,
+        xml: `<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+
+
+  <mxCell id="2" value="Lamp doesn't work" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#ffcccc;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
+    <mxGeometry x="140" y="40" width="180" height="60" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="3" value="" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;" edge="1" parent="1" source="2" target="4">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="4" value="Lamp&lt;br&gt;plugged in?" style="rhombus;whiteSpace=wrap;html=1;fillColor=#ffff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
+    <mxGeometry x="130" y="150" width="200" height="200" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="5" value="No" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="4" target="6">
+    <mxGeometry x="-0.2" relative="1" as="geometry">
+      <mxPoint as="offset"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="6" value="Plug in lamp" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#99ff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
+    <mxGeometry x="420" y="220" width="200" height="60" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="7" value="Yes" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="4" target="8">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="8" value="Bulb&lt;br&gt;burned out?" style="rhombus;whiteSpace=wrap;html=1;fillColor=#ffff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
+    <mxGeometry x="130" y="400" width="200" height="200" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="9" value="Yes" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="8" target="10">
+    <mxGeometry x="-0.2" relative="1" as="geometry">
+      <mxPoint as="offset"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="10" value="Replace bulb" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#99ff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
+    <mxGeometry x="420" y="470" width="200" height="60" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="11" value="No" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="8" target="12">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="12" value="Repair lamp" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#99ff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
+    <mxGeometry x="130" y="650" width="200" height="60" as="geometry"/>
+  </mxCell>
+</root>`,
+    },
+    {
+        promptText: "Draw a cat for me",
+        hasImage: false,
+        xml: `<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+
+
+  <mxCell id="2" value="" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
+    <mxGeometry x="300" y="150" width="120" height="120" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="3" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;rotation=30;" vertex="1" parent="1">
+    <mxGeometry x="280" y="120" width="50" height="60" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="4" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;rotation=-30;" vertex="1" parent="1">
+    <mxGeometry x="390" y="120" width="50" height="60" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="5" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFB6C1;strokeColor=none;rotation=30;" vertex="1" parent="1">
+    <mxGeometry x="290" y="135" width="30" height="35" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="6" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFB6C1;strokeColor=none;rotation=-30;" vertex="1" parent="1">
+    <mxGeometry x="400" y="135" width="30" height="35" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="7" value="" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;fillColor=#000000;strokeColor=#000000;" vertex="1" parent="1">
+    <mxGeometry x="325" y="185" width="15" height="15" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="8" value="" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;fillColor=#000000;strokeColor=#000000;" vertex="1" parent="1">
+    <mxGeometry x="380" y="185" width="15" height="15" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="9" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFB6C1;strokeColor=#000000;strokeWidth=1;rotation=180;" vertex="1" parent="1">
+    <mxGeometry x="350" y="210" width="20" height="15" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="10" value="" style="curved=1;endArrow=none;html=1;strokeColor=#000000;strokeWidth=2;exitX=0.5;exitY=1;exitDx=0;exitDy=0;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="360" y="220" as="sourcePoint"/>
+      <mxPoint x="340" y="235" as="targetPoint"/>
+      <Array as="points">
+        <mxPoint x="355" y="230"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="11" value="" style="curved=1;endArrow=none;html=1;strokeColor=#000000;strokeWidth=2;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="360" y="220" as="sourcePoint"/>
+      <mxPoint x="380" y="235" as="targetPoint"/>
+      <Array as="points">
+        <mxPoint x="365" y="230"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="12" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="310" y="200" as="sourcePoint"/>
+      <mxPoint x="260" y="195" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="13" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="310" y="210" as="sourcePoint"/>
+      <mxPoint x="260" y="210" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="14" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="310" y="220" as="sourcePoint"/>
+      <mxPoint x="260" y="225" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="15" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="410" y="200" as="sourcePoint"/>
+      <mxPoint x="460" y="195" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="16" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="410" y="210" as="sourcePoint"/>
+      <mxPoint x="460" y="210" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="17" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="410" y="220" as="sourcePoint"/>
+      <mxPoint x="460" y="225" as="targetPoint"/>
+    </mxGeometry>
+  </mxCell>
+
+
+  <mxCell id="18" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
+    <mxGeometry x="285" y="250" width="150" height="180" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="19" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFFFFF;strokeColor=none;" vertex="1" parent="1">
+    <mxGeometry x="315" y="280" width="90" height="120" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="20" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
+    <mxGeometry x="300" y="410" width="40" height="50" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="21" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
+    <mxGeometry x="380" y="410" width="40" height="50" as="geometry"/>
+  </mxCell>
+
+
+  <mxCell id="22" value="" style="curved=1;endArrow=none;html=1;strokeColor=#000000;strokeWidth=3;fillColor=#FFE6CC;" edge="1" parent="1">
+    <mxGeometry width="50" height="50" relative="1" as="geometry">
+      <mxPoint x="285" y="340" as="sourcePoint"/>
+      <mxPoint x="240" y="260" as="targetPoint"/>
+      <Array as="points">
+        <mxPoint x="260" y="350"/>
+        <mxPoint x="240" y="320"/>
+        <mxPoint x="235" y="290"/>
+      </Array>
+    </mxGeometry>
+  </mxCell>
+
+</root>`,
+    },
+]
+
+export function findCachedResponse(
+    promptText: string,
+    hasImage: boolean,
+): CachedResponse | undefined {
+    return CACHED_EXAMPLE_RESPONSES.find(
+        (c) =>
+            c.promptText === promptText &&
+            c.hasImage === hasImage &&
+            c.xml !== "",
+    )
+}

lib/langfuse.ts

@@ -0,0 +1,107 @@
+import { LangfuseClient } from "@langfuse/client"
+import { observe, updateActiveTrace } from "@langfuse/tracing"
+import * as api from "@opentelemetry/api"
+
+// Singleton LangfuseClient instance for direct API calls
+let langfuseClient: LangfuseClient | null = null
+
+export function getLangfuseClient(): LangfuseClient | null {
+    if (!process.env.LANGFUSE_PUBLIC_KEY || !process.env.LANGFUSE_SECRET_KEY) {
+        return null
+    }
+
+    if (!langfuseClient) {
+        langfuseClient = new LangfuseClient({
+            publicKey: process.env.LANGFUSE_PUBLIC_KEY,
+            secretKey: process.env.LANGFUSE_SECRET_KEY,
+            baseUrl: process.env.LANGFUSE_BASEURL,
+        })
+    }
+
+    return langfuseClient
+}
+
+// Check if Langfuse is configured
+export function isLangfuseEnabled(): boolean {
+    return !!process.env.LANGFUSE_PUBLIC_KEY
+}
+
+// Update trace with input data at the start of request
+export function setTraceInput(params: {
+    input: string
+    sessionId?: string
+    userId?: string
+}) {
+    if (!isLangfuseEnabled()) return
+
+    updateActiveTrace({
+        name: "chat",
+        input: params.input,
+        sessionId: params.sessionId,
+        userId: params.userId,
+    })
+}
+
+// Update trace with output and end the span
+export function setTraceOutput(
+    output: string,
+    usage?: { promptTokens?: number; completionTokens?: number },
+) {
+    if (!isLangfuseEnabled()) return
+
+    updateActiveTrace({ output })
+
+    const activeSpan = api.trace.getActiveSpan()
+    if (activeSpan) {
+        // Manually set usage attributes since AI SDK Bedrock streaming doesn't provide them
+        if (usage?.promptTokens) {
+            activeSpan.setAttribute("ai.usage.promptTokens", usage.promptTokens)
+            activeSpan.setAttribute(
+                "gen_ai.usage.input_tokens",
+                usage.promptTokens,
+            )
+        }
+        if (usage?.completionTokens) {
+            activeSpan.setAttribute(
+                "ai.usage.completionTokens",
+                usage.completionTokens,
+            )
+            activeSpan.setAttribute(
+                "gen_ai.usage.output_tokens",
+                usage.completionTokens,
+            )
+        }
+        activeSpan.end()
+    }
+}
+
+// Get telemetry config for streamText
+export function getTelemetryConfig(params: {
+    sessionId?: string
+    userId?: string
+}) {
+    if (!isLangfuseEnabled()) return undefined
+
+    return {
+        isEnabled: true,
+        // Disable automatic input recording to avoid uploading large base64 images to Langfuse media
+        // User text input is recorded manually via setTraceInput
+        recordInputs: false,
+        recordOutputs: true,
+        metadata: {
+            sessionId: params.sessionId,
+            userId: params.userId,
+        },
+    }
+}
+
+// Wrap a handler with Langfuse observe
+export function wrapWithObserve<T>(
+    handler: (req: Request) => Promise<T>,
+): (req: Request) => Promise<T> {
+    if (!isLangfuseEnabled()) {
+        return handler
+    }
+
+    return observe(handler, { name: "chat", endOnExit: false })
+}

lib/system-prompts.ts

@@ -0,0 +1,337 @@
+/**
+ * System prompts for different AI models
+ * Extended prompt is used for models with higher cache token minimums (Opus 4.5, Haiku 4.5)
+ */
+
+// Default system prompt (~1400 tokens) - works with all models
+export const DEFAULT_SYSTEM_PROMPT = `
+You are an expert diagram creation assistant specializing in draw.io XML generation.
+Your primary function is chat with user and crafting clear, well-organized visual diagrams through precise XML specifications.
+You can see the image that user uploaded.
+
+## App Context
+You are an AI agent (powered by {{MODEL_NAME}}) inside a web app. The interface has:
+- **Left panel**: Draw.io diagram editor where diagrams are rendered
+- **Right panel**: Chat interface where you communicate with the user
+
+You can read and modify diagrams by generating draw.io XML code through tool calls.
+
+## App Features
+1. **Diagram History** (clock icon, bottom-left of chat input): The app automatically saves a snapshot before each AI edit. Users can view the history panel and restore any previous version. Feel free to make changes - nothing is permanently lost.
+2. **Theme Toggle** (palette icon, bottom-left of chat input): Users can switch between minimal UI and sketch-style UI for the draw.io editor.
+3. **Image Upload** (paperclip icon, bottom-left of chat input): Users can upload images for you to analyze and replicate as diagrams.
+4. **Export** (via draw.io toolbar): Users can save diagrams as .drawio, .svg, or .png files.
+5. **Clear Chat** (trash icon, bottom-right of chat input): Clears the conversation and resets the diagram.
+
+You utilize the following tools:
+---Tool1---
+tool name: display_diagram
+description: Display a NEW diagram on draw.io. Use this when creating a diagram from scratch or when major structural changes are needed.
+parameters: {
+  xml: string
+}
+---Tool2---
+tool name: edit_diagram
+description: Edit specific parts of the EXISTING diagram. Use this when making small targeted changes like adding/removing elements, changing labels, or adjusting properties. This is more efficient than regenerating the entire diagram.
+parameters: {
+  edits: Array<{search: string, replace: string}>
+}
+---End of tools---
+
+IMPORTANT: Choose the right tool:
+- Use display_diagram for: Creating new diagrams, major restructuring, or when the current diagram XML is empty
+- Use edit_diagram for: Small modifications, adding/removing elements, changing text/colors, repositioning items
+
+Core capabilities:
+- Generate valid, well-formed XML strings for draw.io diagrams
+- Create professional flowcharts, mind maps, entity diagrams, and technical illustrations
+- Convert user descriptions into visually appealing diagrams using basic shapes and connectors
+- Apply proper spacing, alignment and visual hierarchy in diagram layouts
+- Adapt artistic concepts into abstract diagram representations using available shapes
+- Optimize element positioning to prevent overlapping and maintain readability
+- Structure complex systems into clear, organized visual components
+
+Layout constraints:
+- CRITICAL: Keep all diagram elements within a single page viewport to avoid page breaks
+- Position all elements with x coordinates between 0-800 and y coordinates between 0-600
+- Maximum width for containers (like AWS cloud boxes): 700 pixels
+- Maximum height for containers: 550 pixels
+- Use compact, efficient layouts that fit the entire diagram in one view
+- Start positioning from reasonable margins (e.g., x=40, y=40) and keep elements grouped closely
+- For large diagrams with many elements, use vertical stacking or grid layouts that stay within bounds
+- Avoid spreading elements too far apart horizontally - users should see the complete diagram without a page break line
+
+Note that:
+- Use proper tool calls to generate or edit diagrams;
+  - never return raw XML in text responses,
+  - never use display_diagram to generate messages that you want to send user directly. e.g. to generate a "hello" text box when you want to greet user.
+- Focus on producing clean, professional diagrams that effectively communicate the intended information through thoughtful layout and design choices.
+- When artistic drawings are requested, creatively compose them using standard diagram shapes and connectors while maintaining visual clarity.
+- Return XML only via tool calls, never in text responses.
+- If user asks you to replicate a diagram based on an image, remember to match the diagram style and layout as closely as possible. Especially, pay attention to the lines and shapes, for example, if the lines are straight or curved, and if the shapes are rounded or square.
+- Note that when you need to generate diagram about aws architecture, use **AWS 2025 icons**.
+- NEVER include XML comments (<!-- ... -->) in your generated XML. Draw.io strips comments, which breaks edit_diagram patterns.
+
+When using edit_diagram tool:
+- CRITICAL: Copy search patterns EXACTLY from the "Current diagram XML" in system context - attribute order matters!
+- Always include the element's id attribute for unique targeting: {"search": "<mxCell id=\\"5\\"", ...}
+- Include complete elements (mxCell + mxGeometry) for reliable matching
+- Preserve exact whitespace, indentation, and line breaks
+- BAD: {"search": "value=\\"Label\\"", ...} - too vague, matches multiple elements
+- GOOD: {"search": "<mxCell id=\\"3\\" value=\\"Old\\" style=\\"...\\">", "replace": "<mxCell id=\\"3\\" value=\\"New\\" style=\\"...\\">"}
+- For multiple changes, use separate edits in array
+- RETRY POLICY: If pattern not found, retry up to 3 times with adjusted patterns. After 3 failures, use display_diagram instead.
+
+## Draw.io XML Structure Reference
+
+Basic structure:
+\`\`\`xml
+<mxGraphModel>
+  <root>
+    <mxCell id="0"/>
+    <mxCell id="1" parent="0"/>
+  </root>
+</mxGraphModel>
+\`\`\`
+Note: All other mxCell elements go as siblings after id="1".
+
+CRITICAL RULES:
+1. Always include the two root cells: <mxCell id="0"/> and <mxCell id="1" parent="0"/>
+2. ALL mxCell elements must be DIRECT children of <root> - NEVER nest mxCell inside another mxCell
+3. Use unique sequential IDs for all cells (start from "2" for user content)
+4. Set parent="1" for top-level shapes, or parent="<container-id>" for grouped elements
+
+Shape (vertex) example:
+\`\`\`xml
+<mxCell id="2" value="Label" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+  <mxGeometry x="100" y="100" width="120" height="60" as="geometry"/>
+</mxCell>
+\`\`\`
+
+Connector (edge) example:
+\`\`\`xml
+<mxCell id="3" style="endArrow=classic;html=1;" edge="1" parent="1" source="2" target="4">
+  <mxGeometry relative="1" as="geometry"/>
+</mxCell>
+\`\`\`
+
+Common styles:
+- Shapes: rounded=1 (rounded corners), fillColor=#hex, strokeColor=#hex
+- Edges: endArrow=classic/block/open/none, startArrow=none/classic, curved=1, edgeStyle=orthogonalEdgeStyle
+- Text: fontSize=14, fontStyle=1 (bold), align=center/left/right
+`
+
+// Extended additions (~2600 tokens) - appended for models with 4000 token cache minimum
+const EXTENDED_ADDITIONS = `
+
+## Extended Tool Reference
+
+### display_diagram Details
+
+**VALIDATION RULES** (XML will be rejected if violated):
+1. All mxCell elements must be DIRECT children of <root> - never nested inside other mxCell elements
+2. Every mxCell needs a unique id attribute
+3. Every mxCell (except id="0") needs a valid parent attribute referencing an existing cell
+4. Edge source/target attributes must reference existing cell IDs
+5. Escape special characters in values: &lt; for <, &gt; for >, &amp; for &, &quot; for "
+6. Always start with the two root cells: <mxCell id="0"/><mxCell id="1" parent="0"/>
+
+**Example with swimlanes and edges** (note: all mxCells are siblings under <root>):
+\`\`\`xml
+<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+  <mxCell id="lane1" value="Frontend" style="swimlane;" vertex="1" parent="1">
+    <mxGeometry x="40" y="40" width="200" height="200" as="geometry"/>
+  </mxCell>
+  <mxCell id="step1" value="Step 1" style="rounded=1;" vertex="1" parent="lane1">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <mxCell id="lane2" value="Backend" style="swimlane;" vertex="1" parent="1">
+    <mxGeometry x="280" y="40" width="200" height="200" as="geometry"/>
+  </mxCell>
+  <mxCell id="step2" value="Step 2" style="rounded=1;" vertex="1" parent="lane2">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;" edge="1" parent="1" source="step1" target="step2">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+</root>
+\`\`\`
+
+### edit_diagram Details
+
+**CRITICAL RULES:**
+- Copy-paste the EXACT search pattern from the "Current diagram XML" in system context
+- Do NOT reorder attributes or reformat - the attribute order in draw.io XML varies and you MUST match it exactly
+- Only include the lines that are changing, plus 1-2 surrounding lines for context if needed
+- Break large changes into multiple smaller edits
+- Each search must contain complete lines (never truncate mid-line)
+- First match only - be specific enough to target the right element
+
+**Input Format:**
+\`\`\`json
+{
+  "edits": [
+    {
+      "search": "EXACT lines copied from current XML (preserve attribute order!)",
+      "replace": "Replacement lines"
+    }
+  ]
+}
+\`\`\`
+
+## edit_diagram Best Practices
+
+### Core Principle: Unique & Precise Patterns
+Your search pattern MUST uniquely identify exactly ONE location in the XML. Before writing a search pattern:
+1. Review the "Current diagram XML" in the system context
+2. Identify the exact element(s) to modify by their unique id attribute
+3. Include enough context to ensure uniqueness
+
+### Pattern Construction Rules
+
+**Rule 1: Always include the element's id attribute**
+\`\`\`json
+{"search": "<mxCell id=\\"node5\\"", "replace": "<mxCell id=\\"node5\\" value=\\"New Label\\""}
+\`\`\`
+
+**Rule 2: Include complete XML elements when possible**
+\`\`\`json
+{
+  "search": "<mxCell id=\\"3\\" value=\\"Old\\" style=\\"rounded=1;\\" vertex=\\"1\\" parent=\\"1\\">\\n  <mxGeometry x=\\"100\\" y=\\"100\\" width=\\"120\\" height=\\"60\\" as=\\"geometry\\"/>\\n</mxCell>",
+  "replace": "<mxCell id=\\"3\\" value=\\"New\\" style=\\"rounded=1;\\" vertex=\\"1\\" parent=\\"1\\">\\n  <mxGeometry x=\\"100\\" y=\\"100\\" width=\\"120\\" height=\\"60\\" as=\\"geometry\\"/>\\n</mxCell>"
+}
+\`\`\`
+
+**Rule 3: Preserve exact whitespace and formatting**
+Copy the search pattern EXACTLY from the current XML, including leading spaces, line breaks (\\n), and attribute order.
+
+### Good vs Bad Patterns
+
+**BAD:** \`{"search": "value=\\"Label\\""}\` - Too vague, matches multiple elements
+**BAD:** \`{"search": "<mxCell value=\\"X\\" id=\\"5\\""}\` - Reordered attributes won't match
+**GOOD:** \`{"search": "<mxCell id=\\"5\\" parent=\\"1\\" style=\\"...\\" value=\\"Old\\" vertex=\\"1\\">"}\` - Uses unique id with full context
+
+### Error Recovery
+If edit_diagram fails with "pattern not found":
+1. **First retry**: Check attribute order - copy EXACTLY from current XML
+2. **Second retry**: Expand context - include more surrounding lines
+3. **Third retry**: Try matching on just \`<mxCell id="X"\` prefix + full replacement
+4. **After 3 failures**: Fall back to display_diagram to regenerate entire diagram
+
+## Common Style Properties
+
+### Shape Styles
+- rounded=1, fillColor=#hex, strokeColor=#hex, strokeWidth=2
+- whiteSpace=wrap, html=1, opacity=50, shadow=1, glass=1
+
+### Edge/Connector Styles
+- endArrow=classic/block/open/oval/diamond/none, startArrow=none/classic
+- curved=1, edgeStyle=orthogonalEdgeStyle, strokeWidth=2
+- dashed=1, dashPattern=3 3, flowAnimation=1
+
+### Text Styles
+- fontSize=14, fontStyle=1 (1=bold, 2=italic, 4=underline, 3=bold+italic)
+- fontColor=#hex, align=center/left/right, verticalAlign=middle/top/bottom
+
+## Common Shape Types
+
+### Basic Shapes
+- Rectangle: rounded=0;whiteSpace=wrap;html=1;
+- Rounded Rectangle: rounded=1;whiteSpace=wrap;html=1;
+- Ellipse/Circle: ellipse;whiteSpace=wrap;html=1;aspect=fixed;
+- Diamond: rhombus;whiteSpace=wrap;html=1;
+- Cylinder: shape=cylinder3;whiteSpace=wrap;html=1;
+
+### Flowchart Shapes
+- Process: rounded=1;whiteSpace=wrap;html=1;
+- Decision: rhombus;whiteSpace=wrap;html=1;
+- Start/End: ellipse;whiteSpace=wrap;html=1;
+- Document: shape=document;whiteSpace=wrap;html=1;
+- Database: shape=cylinder3;whiteSpace=wrap;html=1;
+
+### Container Types
+- Swimlane: swimlane;whiteSpace=wrap;html=1;
+- Group Box: rounded=1;whiteSpace=wrap;html=1;container=1;collapsible=0;
+
+## Container/Group Example
+\`\`\`xml
+<mxCell id="container1" value="Group Title" style="swimlane;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+  <mxGeometry x="40" y="40" width="200" height="200" as="geometry"/>
+</mxCell>
+<mxCell id="child1" value="Child Element" style="rounded=1;" vertex="1" parent="container1">
+  <mxGeometry x="20" y="40" width="160" height="40" as="geometry"/>
+</mxCell>
+\`\`\`
+
+## Example: Complete Flowchart
+
+\`\`\`xml
+<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+  <mxCell id="start" value="Start" style="ellipse;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;" vertex="1" parent="1">
+    <mxGeometry x="200" y="40" width="100" height="60" as="geometry"/>
+  </mxCell>
+  <mxCell id="process1" value="Process Step" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;" vertex="1" parent="1">
+    <mxGeometry x="175" y="140" width="150" height="60" as="geometry"/>
+  </mxCell>
+  <mxCell id="decision" value="Decision?" style="rhombus;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;" vertex="1" parent="1">
+    <mxGeometry x="175" y="240" width="150" height="100" as="geometry"/>
+  </mxCell>
+  <mxCell id="end" value="End" style="ellipse;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;" vertex="1" parent="1">
+    <mxGeometry x="200" y="380" width="100" height="60" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;html=1;" edge="1" parent="1" source="start" target="process1">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge2" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;html=1;" edge="1" parent="1" source="process1" target="decision">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge3" value="Yes" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;html=1;" edge="1" parent="1" source="decision" target="end">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+</root>
+\`\`\`
+`
+
+// Extended system prompt = DEFAULT + EXTENDED_ADDITIONS
+export const EXTENDED_SYSTEM_PROMPT = DEFAULT_SYSTEM_PROMPT + EXTENDED_ADDITIONS
+
+// Model patterns that require extended prompt (4000 token cache minimum)
+// These patterns match Opus 4.5 and Haiku 4.5 model IDs
+const EXTENDED_PROMPT_MODEL_PATTERNS = [
+    "claude-opus-4-5", // Matches any Opus 4.5 variant
+    "claude-haiku-4-5", // Matches any Haiku 4.5 variant
+]
+
+/**
+ * Get the appropriate system prompt based on the model ID
+ * Uses extended prompt for Opus 4.5 and Haiku 4.5 which have 4000 token cache minimum
+ * @param modelId - The AI model ID from environment
+ * @returns The system prompt string
+ */
+export function getSystemPrompt(modelId?: string): string {
+    const modelName = modelId || "AI"
+
+    let prompt: string
+    if (
+        modelId &&
+        EXTENDED_PROMPT_MODEL_PATTERNS.some((pattern) =>
+            modelId.includes(pattern),
+        )
+    ) {
+        console.log(
+            `[System Prompt] Using EXTENDED prompt for model: ${modelId}`,
+        )
+        prompt = EXTENDED_SYSTEM_PROMPT
+    } else {
+        console.log(
+            `[System Prompt] Using DEFAULT prompt for model: ${modelId || "unknown"}`,
+        )
+        prompt = DEFAULT_SYSTEM_PROMPT
+    }
+
+    return prompt.replace("{{MODEL_NAME}}", modelName)
+}

lib/utils.ts

@@ -1,6 +1,6 @@
-import { clsx, type ClassValue } from "clsx"
+import { type ClassValue, clsx } from "clsx"
+import * as pako from "pako"
 import { twMerge } from "tailwind-merge"
-import * as pako from 'pako';
 
 export function cn(...inputs: ClassValue[]) {
     return twMerge(clsx(inputs))
@@ -12,45 +12,45 @@ export function cn(...inputs: ClassValue[]) {
  * @param indent - The indentation string (default: '  ')
  * @returns Formatted XML string
  */
-export function formatXML(xml: string, indent: string = '  '): string {
-  let formatted = '';
-  let pad = 0;
+export function formatXML(xml: string, indent: string = "  "): string {
+    let formatted = ""
+    let pad = 0
 
     // Remove existing whitespace between tags
-  xml = xml.replace(/>\s*</g, '><').trim();
+    xml = xml.replace(/>\s*</g, "><").trim()
 
     // Split on tags
-  const tags = xml.split(/(?=<)|(?<=>)/g).filter(Boolean);
+    const tags = xml.split(/(?=<)|(?<=>)/g).filter(Boolean)
 
     tags.forEach((node) => {
         if (node.match(/^<\/\w/)) {
             // Closing tag - decrease indent
-      pad = Math.max(0, pad - 1);
-      formatted += indent.repeat(pad) + node + '\n';
-    } else if (node.match(/^<\w[^>]*[^\/]>.*$/)) {
+            pad = Math.max(0, pad - 1)
+            formatted += indent.repeat(pad) + node + "\n"
+        } else if (node.match(/^<\w[^>]*[^/]>.*$/)) {
             // Opening tag
-      formatted += indent.repeat(pad) + node;
+            formatted += indent.repeat(pad) + node
             // Only add newline if next item is a tag
-      const nextIndex = tags.indexOf(node) + 1;
-      if (nextIndex < tags.length && tags[nextIndex].startsWith('<')) {
-        formatted += '\n';
+            const nextIndex = tags.indexOf(node) + 1
+            if (nextIndex < tags.length && tags[nextIndex].startsWith("<")) {
+                formatted += "\n"
                 if (!node.match(/^<\w[^>]*\/>$/)) {
-          pad++;
+                    pad++
                 }
             }
         } else if (node.match(/^<\w[^>]*\/>$/)) {
             // Self-closing tag
-      formatted += indent.repeat(pad) + node + '\n';
-    } else if (node.startsWith('<')) {
+            formatted += indent.repeat(pad) + node + "\n"
+        } else if (node.startsWith("<")) {
             // Other tags (like <?xml)
-      formatted += indent.repeat(pad) + node + '\n';
+            formatted += indent.repeat(pad) + node + "\n"
         } else {
             // Text content
-      formatted += node;
+            formatted += node
         }
-  });
+    })
 
-  return formatted.trim();
+    return formatted.trim()
 }
 
 /**
@@ -63,22 +63,24 @@ export function formatXML(xml: string, indent: string = '  '): string {
 export function convertToLegalXml(xmlString: string): string {
     // This regex will match either self-closing <mxCell .../> or a block element
     // <mxCell ...> ... </mxCell>. Unfinished ones are left out because they don't match.
-  const regex = /<mxCell\b[^>]*(?:\/>|>([\s\S]*?)<\/mxCell>)/g;
-  let match: RegExpExecArray | null;
-  let result = "<root>\n";
+    const regex = /<mxCell\b[^>]*(?:\/>|>([\s\S]*?)<\/mxCell>)/g
+    let match: RegExpExecArray | null
+    let result = "<root>\n"
 
     while ((match = regex.exec(xmlString)) !== null) {
         // match[0] contains the entire matched mxCell block
         // Indent each line of the matched block for readability.
-    const formatted = match[0].split('\n').map(line => "    " + line.trim()).join('\n');
-    result += formatted + "\n";
+        const formatted = match[0]
+            .split("\n")
+            .map((line) => "    " + line.trim())
+            .join("\n")
+        result += formatted + "\n"
     }
-  result += "</root>";
+    result += "</root>"
 
-  return result;
+    return result
 }
 
-
 /**
  * Replace nodes in a Draw.io XML diagram
  * @param currentXML - The original Draw.io XML string
@@ -88,94 +90,130 @@ export function convertToLegalXml(xmlString: string): string {
 export function replaceNodes(currentXML: string, nodes: string): string {
     // Check for valid inputs
     if (!currentXML || !nodes) {
-    throw new Error("Both currentXML and nodes must be provided");
+        throw new Error("Both currentXML and nodes must be provided")
     }
 
     try {
         // Parse the XML strings to create DOM objects
-    const parser = new DOMParser();
-    const currentDoc = parser.parseFromString(currentXML, "text/xml");
+        const parser = new DOMParser()
+        const currentDoc = parser.parseFromString(currentXML, "text/xml")
 
         // Handle nodes input - if it doesn't contain <root>, wrap it
-    let nodesString = nodes;
+        let nodesString = nodes
         if (!nodes.includes("<root>")) {
-      nodesString = `<root>${nodes}</root>`;
+            nodesString = `<root>${nodes}</root>`
         }
 
-    const nodesDoc = parser.parseFromString(nodesString, "text/xml");
+        const nodesDoc = parser.parseFromString(nodesString, "text/xml")
 
         // Find the root element in the current document
-    let currentRoot = currentDoc.querySelector("mxGraphModel > root");
+        let currentRoot = currentDoc.querySelector("mxGraphModel > root")
         if (!currentRoot) {
             // If no root element is found, create the proper structure
-      const mxGraphModel = currentDoc.querySelector("mxGraphModel") ||
-        currentDoc.createElement("mxGraphModel");
+            const mxGraphModel =
+                currentDoc.querySelector("mxGraphModel") ||
+                currentDoc.createElement("mxGraphModel")
 
             if (!currentDoc.contains(mxGraphModel)) {
-        currentDoc.appendChild(mxGraphModel);
+                currentDoc.appendChild(mxGraphModel)
             }
 
-      currentRoot = currentDoc.createElement("root");
-      mxGraphModel.appendChild(currentRoot);
+            currentRoot = currentDoc.createElement("root")
+            mxGraphModel.appendChild(currentRoot)
         }
 
         // Find the root element in the nodes document
-    const nodesRoot = nodesDoc.querySelector("root");
+        const nodesRoot = nodesDoc.querySelector("root")
         if (!nodesRoot) {
-      throw new Error("Invalid nodes: Could not find or create <root> element");
+            throw new Error(
+                "Invalid nodes: Could not find or create <root> element",
+            )
         }
 
         // Clear all existing child elements from the current root
         while (currentRoot.firstChild) {
-      currentRoot.removeChild(currentRoot.firstChild);
+            currentRoot.removeChild(currentRoot.firstChild)
         }
 
         // Ensure the base cells exist
         const hasCell0 = Array.from(nodesRoot.childNodes).some(
-      node => node.nodeName === "mxCell" &&
-        (node as Element).getAttribute("id") === "0"
-    );
+            (node) =>
+                node.nodeName === "mxCell" &&
+                (node as Element).getAttribute("id") === "0",
+        )
 
         const hasCell1 = Array.from(nodesRoot.childNodes).some(
-      node => node.nodeName === "mxCell" &&
-        (node as Element).getAttribute("id") === "1"
-    );
+            (node) =>
+                node.nodeName === "mxCell" &&
+                (node as Element).getAttribute("id") === "1",
+        )
 
         // Copy all child nodes from the nodes root to the current root
-    Array.from(nodesRoot.childNodes).forEach(node => {
-      const importedNode = currentDoc.importNode(node, true);
-      currentRoot.appendChild(importedNode);
-    });
+        Array.from(nodesRoot.childNodes).forEach((node) => {
+            const importedNode = currentDoc.importNode(node, true)
+            currentRoot.appendChild(importedNode)
+        })
 
         // Add default cells if they don't exist
         if (!hasCell0) {
-      const cell0 = currentDoc.createElement("mxCell");
-      cell0.setAttribute("id", "0");
-      currentRoot.insertBefore(cell0, currentRoot.firstChild);
+            const cell0 = currentDoc.createElement("mxCell")
+            cell0.setAttribute("id", "0")
+            currentRoot.insertBefore(cell0, currentRoot.firstChild)
         }
 
         if (!hasCell1) {
-      const cell1 = currentDoc.createElement("mxCell");
-      cell1.setAttribute("id", "1");
-      cell1.setAttribute("parent", "0");
+            const cell1 = currentDoc.createElement("mxCell")
+            cell1.setAttribute("id", "1")
+            cell1.setAttribute("parent", "0")
 
             // Insert after cell0 if possible
-      const cell0 = currentRoot.querySelector('mxCell[id="0"]');
-      if (cell0 && cell0.nextSibling) {
-        currentRoot.insertBefore(cell1, cell0.nextSibling);
+            const cell0 = currentRoot.querySelector('mxCell[id="0"]')
+            if (cell0?.nextSibling) {
+                currentRoot.insertBefore(cell1, cell0.nextSibling)
             } else {
-        currentRoot.appendChild(cell1);
+                currentRoot.appendChild(cell1)
             }
         }
 
         // Convert the modified DOM back to a string
-    const serializer = new XMLSerializer();
-    return serializer.serializeToString(currentDoc);
+        const serializer = new XMLSerializer()
+        return serializer.serializeToString(currentDoc)
     } catch (error) {
-    throw new Error(`Error replacing nodes: ${error}`);
+        throw new Error(`Error replacing nodes: ${error}`)
     }
 }
 
+/**
+ * Create a character count dictionary from a string
+ * Used for attribute-order agnostic comparison
+ */
+function charCountDict(str: string): Map<string, number> {
+    const dict = new Map<string, number>()
+    for (const char of str) {
+        dict.set(char, (dict.get(char) || 0) + 1)
+    }
+    return dict
+}
+
+/**
+ * Compare two strings by character frequency (order-agnostic)
+ */
+function sameCharFrequency(a: string, b: string): boolean {
+    const trimmedA = a.trim()
+    const trimmedB = b.trim()
+    if (trimmedA.length !== trimmedB.length) return false
+
+    const dictA = charCountDict(trimmedA)
+    const dictB = charCountDict(trimmedB)
+
+    if (dictA.size !== dictB.size) return false
+
+    for (const [char, count] of dictA) {
+        if (dictB.get(char) !== count) return false
+    }
+    return true
+}
+
 /**
  * Replace specific parts of XML content using search and replace pairs
  * @param xmlContent - The original XML string
@@ -184,77 +222,88 @@ export function replaceNodes(currentXML: string, nodes: string): string {
  */
 export function replaceXMLParts(
     xmlContent: string,
-  searchReplacePairs: Array<{ search: string; replace: string }>
+    searchReplacePairs: Array<{ search: string; replace: string }>,
 ): string {
     // Format the XML first to ensure consistent line breaks
-  let result = formatXML(xmlContent);
-  let lastProcessedIndex = 0;
+    let result = formatXML(xmlContent)
+    let lastProcessedIndex = 0
 
     for (const { search, replace } of searchReplacePairs) {
         // Also format the search content for consistency
-    const formattedSearch = formatXML(search);
-    const searchLines = formattedSearch.split('\n');
+        const formattedSearch = formatXML(search)
+        const searchLines = formattedSearch.split("\n")
 
         // Split into lines for exact line matching
-    const resultLines = result.split('\n');
+        const resultLines = result.split("\n")
 
         // Remove trailing empty line if exists (from the trailing \n in search content)
-    if (searchLines[searchLines.length - 1] === '') {
-      searchLines.pop();
+        if (searchLines[searchLines.length - 1] === "") {
+            searchLines.pop()
         }
 
         // Find the line number where lastProcessedIndex falls
-    let startLineNum = 0;
-    let currentIndex = 0;
-    while (currentIndex < lastProcessedIndex && startLineNum < resultLines.length) {
-      currentIndex += resultLines[startLineNum].length + 1; // +1 for \n
-      startLineNum++;
+        let startLineNum = 0
+        let currentIndex = 0
+        while (
+            currentIndex < lastProcessedIndex &&
+            startLineNum < resultLines.length
+        ) {
+            currentIndex += resultLines[startLineNum].length + 1 // +1 for \n
+            startLineNum++
         }
 
         // Try to find exact match starting from lastProcessedIndex
-    let matchFound = false;
-    let matchStartLine = -1;
-    let matchEndLine = -1;
+        let matchFound = false
+        let matchStartLine = -1
+        let matchEndLine = -1
 
         // First try: exact match
-    for (let i = startLineNum; i <= resultLines.length - searchLines.length; i++) {
-      let matches = true;
+        for (
+            let i = startLineNum;
+            i <= resultLines.length - searchLines.length;
+            i++
+        ) {
+            let matches = true
 
             for (let j = 0; j < searchLines.length; j++) {
                 if (resultLines[i + j] !== searchLines[j]) {
-          matches = false;
-          break;
+                    matches = false
+                    break
                 }
             }
 
             if (matches) {
-        matchStartLine = i;
-        matchEndLine = i + searchLines.length;
-        matchFound = true;
-        break;
+                matchStartLine = i
+                matchEndLine = i + searchLines.length
+                matchFound = true
+                break
             }
         }
 
         // Second try: line-trimmed match (fallback)
         if (!matchFound) {
-      for (let i = startLineNum; i <= resultLines.length - searchLines.length; i++) {
-        let matches = true;
+            for (
+                let i = startLineNum;
+                i <= resultLines.length - searchLines.length;
+                i++
+            ) {
+                let matches = true
 
                 for (let j = 0; j < searchLines.length; j++) {
-          const originalTrimmed = resultLines[i + j].trim();
-          const searchTrimmed = searchLines[j].trim();
+                    const originalTrimmed = resultLines[i + j].trim()
+                    const searchTrimmed = searchLines[j].trim()
 
                     if (originalTrimmed !== searchTrimmed) {
-            matches = false;
-            break;
+                        matches = false
+                        break
                     }
                 }
 
                 if (matches) {
-          matchStartLine = i;
-          matchEndLine = i + searchLines.length;
-          matchFound = true;
-          break;
+                    matchStartLine = i
+                    matchEndLine = i + searchLines.length
+                    matchFound = true
+                    break
                 }
             }
         }
@@ -262,114 +311,298 @@ export function replaceXMLParts(
         // Third try: substring match as last resort (for single-line XML)
         if (!matchFound) {
             // Try to find as a substring in the entire content
-      const searchStr = search.trim();
-      const resultStr = result;
-      const index = resultStr.indexOf(searchStr);
+            const searchStr = search.trim()
+            const resultStr = result
+            const index = resultStr.indexOf(searchStr)
 
             if (index !== -1) {
                 // Found as substring - replace it
-        result = resultStr.substring(0, index) + replace.trim() + resultStr.substring(index + searchStr.length);
+                result =
+                    resultStr.substring(0, index) +
+                    replace.trim() +
+                    resultStr.substring(index + searchStr.length)
                 // Re-format after substring replacement
-        result = formatXML(result);
-        continue; // Skip the line-based replacement below
+                result = formatXML(result)
+                continue // Skip the line-based replacement below
+            }
+        }
+
+        // Fourth try: character frequency match (attribute-order agnostic)
+        // This handles cases where the model generates XML with different attribute order
+        if (!matchFound) {
+            for (
+                let i = startLineNum;
+                i <= resultLines.length - searchLines.length;
+                i++
+            ) {
+                let matches = true
+
+                for (let j = 0; j < searchLines.length; j++) {
+                    if (
+                        !sameCharFrequency(resultLines[i + j], searchLines[j])
+                    ) {
+                        matches = false
+                        break
+                    }
+                }
+
+                if (matches) {
+                    matchStartLine = i
+                    matchEndLine = i + searchLines.length
+                    matchFound = true
+                    break
+                }
+            }
+        }
+
+        // Fifth try: Match by mxCell id attribute
+        // Extract id from search pattern and find the element with that id
+        if (!matchFound) {
+            const idMatch = search.match(/id="([^"]+)"/)
+            if (idMatch) {
+                const searchId = idMatch[1]
+                // Find lines that contain this id
+                for (let i = startLineNum; i < resultLines.length; i++) {
+                    if (resultLines[i].includes(`id="${searchId}"`)) {
+                        // Found the element with matching id
+                        // Now find the extent of this element (it might span multiple lines)
+                        let endLine = i + 1
+                        const line = resultLines[i].trim()
+
+                        // Check if it's a self-closing tag or has children
+                        if (!line.endsWith("/>")) {
+                            // Find the closing tag or the end of the mxCell block
+                            let depth = 1
+                            while (endLine < resultLines.length && depth > 0) {
+                                const currentLine = resultLines[endLine].trim()
+                                if (
+                                    currentLine.startsWith("<") &&
+                                    !currentLine.startsWith("</") &&
+                                    !currentLine.endsWith("/>")
+                                ) {
+                                    depth++
+                                } else if (currentLine.startsWith("</")) {
+                                    depth--
+                                }
+                                endLine++
+                            }
+                        }
+
+                        matchStartLine = i
+                        matchEndLine = endLine
+                        matchFound = true
+                        break
+                    }
+                }
             }
         }
 
         if (!matchFound) {
-      throw new Error(`Search pattern not found in the diagram. The pattern may not exist in the current structure.`);
+            throw new Error(
+                `Search pattern not found in the diagram. The pattern may not exist in the current structure.`,
+            )
         }
 
         // Replace the matched lines
-    const replaceLines = replace.split('\n');
+        const replaceLines = replace.split("\n")
 
         // Remove trailing empty line if exists
-    if (replaceLines[replaceLines.length - 1] === '') {
-      replaceLines.pop();
+        if (replaceLines[replaceLines.length - 1] === "") {
+            replaceLines.pop()
         }
 
         // Perform the replacement
         const newResultLines = [
             ...resultLines.slice(0, matchStartLine),
             ...replaceLines,
-      ...resultLines.slice(matchEndLine)
-    ];
+            ...resultLines.slice(matchEndLine),
+        ]
 
-    result = newResultLines.join('\n');
+        result = newResultLines.join("\n")
 
         // Update lastProcessedIndex to the position after the replacement
-    lastProcessedIndex = 0;
+        lastProcessedIndex = 0
         for (let i = 0; i < matchStartLine + replaceLines.length; i++) {
-      lastProcessedIndex += newResultLines[i].length + 1;
+            lastProcessedIndex += newResultLines[i].length + 1
         }
     }
 
-  return result;
+    return result
+}
+
+/**
+ * Validates draw.io XML structure for common issues
+ * @param xml - The XML string to validate
+ * @returns null if valid, error message string if invalid
+ */
+export function validateMxCellStructure(xml: string): string | null {
+    const parser = new DOMParser()
+    const doc = parser.parseFromString(xml, "text/xml")
+
+    // Check for XML parsing errors (includes unescaped special characters)
+    const parseError = doc.querySelector("parsererror")
+    if (parseError) {
+        return `Invalid XML: The XML contains syntax errors (likely unescaped special characters like <, >, & in attribute values). Please escape special characters: use &lt; for <, &gt; for >, &amp; for &, &quot; for ". Regenerate the diagram with properly escaped values.`
+    }
+
+    // Get all mxCell elements once for all validations
+    const allCells = doc.querySelectorAll("mxCell")
+
+    // Single pass: collect IDs, check for duplicates, nesting, orphans, and invalid parents
+    const cellIds = new Set<string>()
+    const duplicateIds: string[] = []
+    const nestedCells: string[] = []
+    const orphanCells: string[] = []
+    const invalidParents: { id: string; parent: string }[] = []
+    const edgesToValidate: {
+        id: string
+        source: string | null
+        target: string | null
+    }[] = []
+
+    allCells.forEach((cell) => {
+        const id = cell.getAttribute("id")
+        const parent = cell.getAttribute("parent")
+        const isEdge = cell.getAttribute("edge") === "1"
+
+        // Check for duplicate IDs
+        if (id) {
+            if (cellIds.has(id)) {
+                duplicateIds.push(id)
+            } else {
+                cellIds.add(id)
+            }
+        }
+
+        // Check for nested mxCell (parent element is also mxCell)
+        if (cell.parentElement?.tagName === "mxCell") {
+            nestedCells.push(id || "unknown")
+        }
+
+        // Check parent attribute (skip root cell id="0")
+        if (id !== "0") {
+            if (!parent) {
+                if (id) orphanCells.push(id)
+            } else {
+                // Store for later validation (after all IDs collected)
+                invalidParents.push({ id: id || "unknown", parent })
+            }
+        }
+
+        // Collect edges for connection validation
+        if (isEdge) {
+            edgesToValidate.push({
+                id: id || "unknown",
+                source: cell.getAttribute("source"),
+                target: cell.getAttribute("target"),
+            })
+        }
+    })
+
+    // Return errors in priority order
+    if (nestedCells.length > 0) {
+        return `Invalid XML: Found nested mxCell elements (IDs: ${nestedCells.slice(0, 3).join(", ")}). All mxCell elements must be direct children of <root>, never nested inside other mxCell elements. Please regenerate the diagram with correct structure.`
+    }
+
+    if (duplicateIds.length > 0) {
+        return `Invalid XML: Found duplicate cell IDs (${duplicateIds.slice(0, 3).join(", ")}). Each mxCell must have a unique ID. Please regenerate the diagram with unique IDs for all elements.`
+    }
+
+    if (orphanCells.length > 0) {
+        return `Invalid XML: Found cells without parent attribute (IDs: ${orphanCells.slice(0, 3).join(", ")}). All mxCell elements (except id="0") must have a parent attribute. Please regenerate the diagram with proper parent references.`
+    }
+
+    // Validate parent references (now that all IDs are collected)
+    const badParents = invalidParents.filter((p) => !cellIds.has(p.parent))
+    if (badParents.length > 0) {
+        const details = badParents
+            .slice(0, 3)
+            .map((p) => `${p.id} (parent: ${p.parent})`)
+            .join(", ")
+        return `Invalid XML: Found cells with invalid parent references (${details}). Parent IDs must reference existing cells. Please regenerate the diagram with valid parent references.`
+    }
+
+    // Validate edge connections
+    const invalidConnections: string[] = []
+    edgesToValidate.forEach((edge) => {
+        if (edge.source && !cellIds.has(edge.source)) {
+            invalidConnections.push(`${edge.id} (source: ${edge.source})`)
+        }
+        if (edge.target && !cellIds.has(edge.target)) {
+            invalidConnections.push(`${edge.id} (target: ${edge.target})`)
+        }
+    })
+
+    if (invalidConnections.length > 0) {
+        return `Invalid XML: Found edges with invalid source/target references (${invalidConnections.slice(0, 3).join(", ")}). Edge source and target must reference existing cell IDs. Please regenerate the diagram with valid edge connections.`
+    }
+
+    return null
 }
 
 export function extractDiagramXML(xml_svg_string: string): string {
     try {
         // 1. Parse the SVG string (using built-in DOMParser in a browser-like environment)
-    const svgString = atob(xml_svg_string.slice(26));
-    const parser = new DOMParser();
-    const svgDoc = parser.parseFromString(svgString, "image/svg+xml");
-    const svgElement = svgDoc.querySelector('svg');
+        const svgString = atob(xml_svg_string.slice(26))
+        const parser = new DOMParser()
+        const svgDoc = parser.parseFromString(svgString, "image/svg+xml")
+        const svgElement = svgDoc.querySelector("svg")
 
         if (!svgElement) {
-      throw new Error("No SVG element found in the input string.");
+            throw new Error("No SVG element found in the input string.")
         }
         // 2. Extract the 'content' attribute
-    const encodedContent = svgElement.getAttribute('content');
+        const encodedContent = svgElement.getAttribute("content")
 
         if (!encodedContent) {
-      throw new Error("SVG element does not have a 'content' attribute.");
+            throw new Error("SVG element does not have a 'content' attribute.")
         }
 
         // 3. Decode HTML entities (using a minimal function)
         function decodeHtmlEntities(str: string) {
-      const textarea = document.createElement('textarea'); // Use built-in element
-      textarea.innerHTML = str;
-      return textarea.value;
+            const textarea = document.createElement("textarea") // Use built-in element
+            textarea.innerHTML = str
+            return textarea.value
         }
-    const xmlContent = decodeHtmlEntities(encodedContent);
+        const xmlContent = decodeHtmlEntities(encodedContent)
 
         // 4. Parse the XML content
-    const xmlDoc = parser.parseFromString(xmlContent, "text/xml");
-    const diagramElement = xmlDoc.querySelector('diagram');
+        const xmlDoc = parser.parseFromString(xmlContent, "text/xml")
+        const diagramElement = xmlDoc.querySelector("diagram")
 
         if (!diagramElement) {
-      throw new Error("No diagram element found");
+            throw new Error("No diagram element found")
         }
         // 5. Extract base64 encoded data
-    const base64EncodedData = diagramElement.textContent;
+        const base64EncodedData = diagramElement.textContent
 
         if (!base64EncodedData) {
-      throw new Error("No encoded data found in the diagram element");
+            throw new Error("No encoded data found in the diagram element")
         }
 
         // 6. Decode base64 data
-    const binaryString = atob(base64EncodedData);
+        const binaryString = atob(base64EncodedData)
 
         // 7. Convert binary string to Uint8Array
-    const len = binaryString.length;
-    const bytes = new Uint8Array(len);
+        const len = binaryString.length
+        const bytes = new Uint8Array(len)
         for (let i = 0; i < len; i++) {
-      bytes[i] = binaryString.charCodeAt(i);
+            bytes[i] = binaryString.charCodeAt(i)
         }
 
         // 8. Decompress data using pako (equivalent to zlib.decompress with wbits=-15)
-    const decompressedData = pako.inflate(bytes, { windowBits: -15 });
+        const decompressedData = pako.inflate(bytes, { windowBits: -15 })
 
         // 9. Convert the decompressed data to a string
-    const decoder = new TextDecoder('utf-8');
-    const decodedString = decoder.decode(decompressedData);
+        const decoder = new TextDecoder("utf-8")
+        const decodedString = decoder.decode(decompressedData)
 
         // Decode URL-encoded content (equivalent to Python's urllib.parse.unquote)
-    const urlDecodedString = decodeURIComponent(decodedString);
-
-    return urlDecodedString;
+        const urlDecodedString = decodeURIComponent(decodedString)
 
+        return urlDecodedString
     } catch (error) {
-    console.error("Error extracting diagram XML:", error);
-    throw error; // Re-throw for caller handling
+        console.error("Error extracting diagram XML:", error)
+        throw error // Re-throw for caller handling
     }
 }

next.config.ts

@@ -1,7 +1,8 @@
-import type { NextConfig } from "next";
+import type { NextConfig } from "next"
 
 const nextConfig: NextConfig = {
     /* config options here */
-};
+    output: "standalone",
+}
 
-export default nextConfig;
+export default nextConfig

package.json

@@ -1,23 +1,35 @@
 {
     "name": "next-ai-draw-io",
-    "version": "0.2.0",
+    "version": "0.3.0",
+    "license": "Apache-2.0",
     "private": true,
     "scripts": {
         "dev": "next dev --turbopack --port 6002",
         "build": "next build",
         "start": "next start --port 6001",
-        "lint": "next lint"
+        "lint": "biome lint .",
+        "format": "biome check --write .",
+        "check": "biome ci",
+        "prepare": "husky"
     },
     "dependencies": {
-        "@ai-sdk/amazon-bedrock": "^3.0.52",
+        "@ai-sdk/amazon-bedrock": "^3.0.62",
         "@ai-sdk/anthropic": "^2.0.44",
         "@ai-sdk/azure": "^2.0.69",
+        "@ai-sdk/deepseek": "^1.0.30",
         "@ai-sdk/google": "^2.0.0",
         "@ai-sdk/openai": "^2.0.19",
         "@ai-sdk/react": "^2.0.22",
+        "@aws-sdk/credential-providers": "^3.943.0",
+        "@langfuse/client": "^4.4.9",
+        "@langfuse/otel": "^4.4.4",
+        "@langfuse/tracing": "^4.4.9",
+        "@next/third-parties": "^16.0.6",
         "@openrouter/ai-sdk-provider": "^1.2.3",
+        "@opentelemetry/sdk-trace-node": "^2.2.0",
         "@radix-ui/react-dialog": "^1.1.6",
         "@radix-ui/react-scroll-area": "^1.2.3",
+        "@radix-ui/react-select": "^2.2.6",
         "@radix-ui/react-slot": "^1.1.2",
         "@radix-ui/react-tooltip": "^1.1.8",
         "@vercel/analytics": "^1.5.0",
@@ -28,24 +40,40 @@
         "clsx": "^2.1.1",
         "jsdom": "^26.0.0",
         "lucide-react": "^0.483.0",
-        "next": "15.2.3",
+        "next": "^16.0.7",
         "ollama-ai-provider-v2": "^1.5.4",
         "pako": "^2.1.0",
+        "prism-react-renderer": "^2.4.1",
         "react": "^19.0.0",
         "react-dom": "^19.0.0",
         "react-drawio": "^1.0.3",
         "react-icons": "^5.5.0",
+        "react-markdown": "^10.1.0",
+        "react-resizable-panels": "^3.0.6",
         "remark-gfm": "^4.0.1",
+        "sonner": "^2.0.7",
         "tailwind-merge": "^3.0.2",
         "tailwindcss-animate": "^1.0.7",
         "zod": "^4.1.12"
     },
+    "lint-staged": {
+        "*.{js,ts,jsx,tsx,json,css}": [
+            "biome check --write --no-errors-on-unmatched",
+            "biome check --no-errors-on-unmatched"
+        ]
+    },
     "devDependencies": {
+        "@biomejs/biome": "2.3.8",
         "@tailwindcss/postcss": "^4",
+        "@tailwindcss/typography": "^0.5.19",
         "@types/node": "^20",
         "@types/pako": "^2.0.3",
         "@types/react": "^19",
         "@types/react-dom": "^19",
+        "eslint": "9.39.1",
+        "eslint-config-next": "16.0.5",
+        "husky": "^9.1.7",
+        "lint-staged": "^16.2.7",
         "tailwindcss": "^4",
         "typescript": "^5"
     }

postcss.config.mjs

@@ -1,5 +1,5 @@
 const config = {
     plugins: ["@tailwindcss/postcss"],
-};
+}
 
-export default config;
+export default config

tsconfig.json

@@ -11,7 +11,7 @@
         "moduleResolution": "bundler",
         "resolveJsonModule": true,
         "isolatedModules": true,
-    "jsx": "preserve",
+        "jsx": "react-jsx",
         "incremental": true,
         "plugins": [
             {
@@ -22,6 +22,12 @@
             "@/*": ["./*"]
         }
     },
-  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts"],
+    "include": [
+        "next-env.d.ts",
+        "**/*.ts",
+        "**/*.tsx",
+        ".next/types/**/*.ts",
+        ".next/dev/types/**/*.ts"
+    ],
     "exclude": ["node_modules"]
 }