feat(showcase): add temporary language switcher for visitors with cookie persistence

app/routers/web.py

@@ -815,6 +815,16 @@ def public_showcase(request: Request, username: str, db: Session = Depends(get_d
     user = db.query(User).filter(User.username == username).first()
     if not user:
         return HTMLResponse("用户不存在", status_code=404)
+
+    # Language: query param > cookie > owner's default
+    from app.i18n import get_languages
+    _avail = get_languages()
+    visitor_lang = request.query_params.get("lang")
+    if not visitor_lang or visitor_lang not in _avail:
+        visitor_lang = request.cookies.get("showcase_lang")
+    if not visitor_lang or visitor_lang not in _avail:
+        visitor_lang = user.language
+
     profiles = db.query(Profile).filter(Profile.user_id == user.id, Profile.showcase_enabled == True).all()
     sent_all, received_all, profile_groups = [], [], []
     for p in profiles:
@@ -837,11 +847,13 @@ def public_showcase(request: Request, username: str, db: Session = Depends(get_d
             profile_groups.append({"profile": p, "sent": p_sent, "received": p_received})
     sent_all.sort(key=lambda c: c.send_time or c.created_at, reverse=True)
     received_all.sort(key=lambda c: c.receive_time or c.created_at, reverse=True)
-    return templates.TemplateResponse("showcase.html", {
+    resp = templates.TemplateResponse("showcase.html", {
         "request": request, "profile_user": user, "mode": user.showcase_mode,
         "profile_groups": profile_groups, "sent_all": sent_all, "received_all": received_all,
-        "lang": user.language,
+        "lang": visitor_lang, "available_languages": _avail,
     })
+    resp.set_cookie("showcase_lang", visitor_lang, max_age=365 * 24 * 3600, httponly=True, samesite="lax")
+    return resp
 
 
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