import { Cloud } from "lucide-react"
import type { ComponentProps, ElementRef, ReactNode } from "react"
import { useEffect, useRef, useState } from "react"
import {
    Command,
    CommandDialog,
    CommandEmpty,
    CommandGroup,
    CommandInput,
    CommandItem,
    CommandList,
    CommandSeparator,
    CommandShortcut,
} from "@/components/ui/command"
import {
    Dialog,
    DialogContent,
    DialogTitle,
    DialogTrigger,
} from "@/components/ui/dialog"
import { cn } from "@/lib/utils"

export type ModelSelectorProps = ComponentProps<typeof Dialog>

export const ModelSelector = (props: ModelSelectorProps) => (
    <Dialog {...props} />
)

export type ModelSelectorTriggerProps = ComponentProps<typeof DialogTrigger>

export const ModelSelectorTrigger = (props: ModelSelectorTriggerProps) => (
    <DialogTrigger {...props} />
)

export type ModelSelectorContentProps = ComponentProps<typeof DialogContent> & {
    title?: ReactNode
}

export const ModelSelectorContent = ({
    className,
    children,
    title = "Model Selector",
    ...props
}: ModelSelectorContentProps) => (
    <DialogContent className={cn("p-0", className)} {...props}>
        <DialogTitle className="sr-only">{title}</DialogTitle>
        <Command className="**:data-[slot=command-input-wrapper]:h-auto">
            {children}
        </Command>
    </DialogContent>
)

export type ModelSelectorDialogProps = ComponentProps<typeof CommandDialog>

export const ModelSelectorDialog = (props: ModelSelectorDialogProps) => (
    <CommandDialog {...props} />
)

export type ModelSelectorInputProps = ComponentProps<typeof CommandInput>

export const ModelSelectorInput = ({
    className,
    ...props
}: ModelSelectorInputProps) => (
    <CommandInput className={cn("h-auto py-3.5", className)} {...props} />
)

export type ModelSelectorListProps = ComponentProps<typeof CommandList>

export const ModelSelectorList = ({
    className,
    ...props
}: ModelSelectorListProps) => {
    const listRef = useRef<ElementRef<typeof CommandList>>(null)
    const [showShadow, setShowShadow] = useState(false)

    useEffect(() => {
        const listElement = listRef.current
        if (!listElement) return

        const checkScroll = () => {
            const { scrollTop, scrollHeight, clientHeight } = listElement
            // Show shadow if there is more content below
            // Using a small threshold to handle fractional pixel rendering
            setShowShadow(
                scrollHeight > Math.ceil(scrollTop + clientHeight) + 1,
            )
        }

        // Initial check
        checkScroll()

        // Event listeners
        listElement.addEventListener("scroll", checkScroll)
        window.addEventListener("resize", checkScroll)

        // Observe content changes (e.g. async loading of items)
        const observer = new MutationObserver(checkScroll)
        observer.observe(listElement, { childList: true, subtree: true })

        return () => {
            listElement.removeEventListener("scroll", checkScroll)
            window.removeEventListener("resize", checkScroll)
            observer.disconnect()
        }
    }, [])

    return (
        <div className="relative">
            <CommandList
                ref={listRef}
                className={cn(
                    // Hide scrollbar on all platforms
                    "[&::-webkit-scrollbar]:hidden [-ms-overflow-style:none] [scrollbar-width:none]",
                    className,
                )}
                {...props}
            />
            {/* Bottom shadow indicator for scrollable content */}
            <div
                className={cn(
                    "pointer-events-none absolute bottom-0 left-0 right-0 h-12 bg-gradient-to-t from-muted/80 via-muted/40 to-transparent transition-opacity duration-200",
                    showShadow ? "opacity-100" : "opacity-0",
                )}
            />
        </div>
    )
}

export type ModelSelectorEmptyProps = ComponentProps<typeof CommandEmpty>

export const ModelSelectorEmpty = (props: ModelSelectorEmptyProps) => (
    <CommandEmpty {...props} />
)

export type ModelSelectorGroupProps = ComponentProps<typeof CommandGroup>

export const ModelSelectorGroup = (props: ModelSelectorGroupProps) => (
    <CommandGroup {...props} />
)

export type ModelSelectorItemProps = ComponentProps<typeof CommandItem>

export const ModelSelectorItem = (props: ModelSelectorItemProps) => (
    <CommandItem {...props} />
)

export type ModelSelectorShortcutProps = ComponentProps<typeof CommandShortcut>

export const ModelSelectorShortcut = (props: ModelSelectorShortcutProps) => (
    <CommandShortcut {...props} />
)

export type ModelSelectorSeparatorProps = ComponentProps<
    typeof CommandSeparator
>

export const ModelSelectorSeparator = (props: ModelSelectorSeparatorProps) => (
    <CommandSeparator {...props} />
)

export type ModelSelectorLogoProps = Omit<
    ComponentProps<"img">,
    "src" | "alt"
> & {
    provider: string
}

export const ModelSelectorLogo = ({
    provider,
    className,
    ...props
}: ModelSelectorLogoProps) => {
    // Use Lucide icon for bedrock since models.dev doesn't have a good AWS icon
    if (provider === "amazon-bedrock") {
        return <Cloud className={cn("size-4", className)} />
    }

    return (
        // biome-ignore lint/performance/noImgElement: External URL from models.dev
        <img
            {...props}
            alt={`${provider} logo`}
            className={cn("size-4 dark:invert", className)}
            height={16}
            src={`https://models.dev/logos/${provider}.svg`}
            width={16}
        />
    )
}

export type ModelSelectorLogoGroupProps = ComponentProps<"div">

export const ModelSelectorLogoGroup = ({
    className,
    ...props
}: ModelSelectorLogoGroupProps) => (
    <div
        className={cn(
            "-space-x-1 flex shrink-0 items-center [&>img]:rounded-full [&>img]:bg-background [&>img]:p-px [&>img]:ring-1 dark:[&>img]:bg-foreground",
            className,
        )}
        {...props}
    />
)

export type ModelSelectorNameProps = ComponentProps<"span">

export const ModelSelectorName = ({
    className,
    ...props
}: ModelSelectorNameProps) => (
    <span className={cn("flex-1 truncate text-left", className)} {...props} />
)

export type ModelSelectorSectionHeaderProps = {
    icon: ReactNode
    label: string
    className?: string
}

export const ModelSelectorSectionHeader = ({
    icon,
    label,
    className,
}: ModelSelectorSectionHeaderProps) => (
    <div
        className={cn(
            "flex items-center gap-2 px-2 py-1.5 text-xs font-semibold text-muted-foreground bg-muted/40 rounded-sm mx-1 mt-1",
            className,
        )}
    >
        <span className="[&>svg]:size-3.5" aria-hidden="true">
            {icon}
        </span>
        <span>{label}</span>
    </div>
)