Update build workflow and language switch extension for improved multilingual support

docs/_ext/language_switch.py

@@ -1,22 +1,21 @@
 """Sphinx extension to inject language switch links between English (en) and Chinese (zh) builds.
-Works for local file:// viewing: replaces the segment /en/_build/html/ with /zh/_build/html/ and vice versa.
-Removes need for hard-coded absolute paths.
+Updated to work with GitHub Pages project URLs like /<repo>/en/... and /<repo>/zh/....
 """
 from docutils import nodes
 
 
 def setup(app):
     app.connect('doctree-resolved', inject_language_switch)
-    return {"version": "0.3", "parallel_read_safe": True}
+    return {"version": "0.4", "parallel_read_safe": True}
 
 
 def inject_language_switch(app, doctree, docname):
     lang = app.config.language or 'en'
     is_en = lang.startswith('en')
-    # Placeholder labels; JS will adjust depending on actual page path
     other_label = '中文' if is_en else 'English'
     current_label = 'English' if is_en else '中文'
 
+    # JS now detects /en/ or /zh/ segment and swaps only the first occurrence
     html = (
         '<div class="lang-switch" style="margin:0 0 1em 0; font-size:0.9em;">'
         f'<a class="lang-other" href="#">{other_label}</a> | '
@@ -24,8 +23,9 @@ def inject_language_switch(app, doctree, docname):
         '</div>'
         '<script>(function(){'
         "var p=window.location.pathname;"
-        "var isEn=p.indexOf('/en/_build/html/')!==-1;"
-        "var other=isEn? p.replace('/en/_build/html/','/zh/_build/html/') : p.replace('/zh/_build/html/','/en/_build/html/');"
+        "var isEn=p.indexOf('/en/')!==-1 && p.indexOf('/zh/')===-1;"
+        "if(p.indexOf('/zh/')!==-1) isEn=false;"
+        "var other = isEn ? p.replace(/\\/en\\//, '/zh/') : p.replace(/\\/zh\\//, '/en/');"
         "var current=p;"
         "var sw=document.querySelector('.lang-switch'); if(!sw) return;"
         "var o=sw.querySelector('.lang-other'); var c=sw.querySelector('.lang-current');"