chore: Perform codebase cleanup and refactor App state management

frontend/src/App.tsx

@@ -1,4 +1,4 @@
-import { useState, useEffect } from "react"
+import { useState, useEffect, createContext, useContext } from "react"
 import { Routes, Route } from "react-router-dom"
 import { MainLayout } from "./components/layout/MainLayout"
 import { LoginForm } from "./components/auth/LoginForm"
@@ -9,12 +9,42 @@ import { ChatService, type MessageResponse } from "./services/chat"
 import { type Conversation } from "./components/layout/HistorySidebar"
 import { registerUnauthorizedCallback } from "./services/api"
 import { Button } from "./components/ui/button"
-import { useTheme } from "./components/theme-provider"
+import { ThemeProvider, useTheme } from "./components/theme-provider"
 
-function App() {
-  const { setThemeLocal } = useTheme()
+// --- Auth Context ---
+interface AuthContextType {
+  isAuthenticated: boolean
+  setIsAuthenticated: (val: boolean) => void
+  user: UserResponse | null
+  setUser: (user: UserResponse | null) => void
+}
+
+const AuthContext = createContext<AuthContextType | undefined>(undefined)
+
+function AuthProvider({ children }: { children: React.ReactNode }) {
   const [isAuthenticated, setIsAuthenticated] = useState(false)
   const [user, setUser] = useState<UserResponse | null>(null)
+
+  return (
+    <AuthContext.Provider value={{ isAuthenticated, setIsAuthenticated, user, setUser }}>
+      {children}
+    </AuthContext.Provider>
+  )
+}
+
+function useAuth() {
+  const context = useContext(AuthContext)
+  if (context === undefined) {
+    throw new Error("useAuth must be used within an AuthProvider")
+  }
+  return context
+}
+
+// --- App Content ---
+function AppContent() {
+  const { setThemeLocal } = useTheme()
+  const { isAuthenticated, setIsAuthenticated, user, setUser } = useAuth()
+  
   const [authMode, setAuthMode] = useState<"login" | "register">("login")
   const [isLoading, setIsLoading] = useState(true)
   const [selectedThreadId, setSelectedThreadId] = useState<string | null>(null)
@@ -22,13 +52,13 @@ function App() {
   const [threadMessages, setThreadMessages] = useState<Record<string, MessageResponse[]>>({})
 
   useEffect(() => {
-    // Register callback to handle session expiration from anywhere in the app
     registerUnauthorizedCallback(() => {
       setIsAuthenticated(false)
       setUser(null)
       setConversations([])
       setSelectedThreadId(null)
       setThreadMessages({})
+      setThemeLocal("light")
     })
 
     const initAuth = async () => {
@@ -39,7 +69,6 @@ function App() {
         if (userData.theme_preference) {
           setThemeLocal(userData.theme_preference)
         }
-        // Load history after successful auth
         loadHistory()
       } catch (err: unknown) {
         console.log("No active session found", err)
@@ -50,7 +79,7 @@ function App() {
     }
 
     initAuth()
-  }, [])
+  }, [setIsAuthenticated, setThemeLocal, setUser])
 
   const loadHistory = async () => {
     try {
@@ -86,13 +115,12 @@ function App() {
       setSelectedThreadId(null)
       setConversations([])
       setThreadMessages({})
+      setThemeLocal("light")
     }
   }
 
   const handleSelectConversation = async (id: string) => {
     setSelectedThreadId(id)
-    // Always fetch messages to avoid stale cache issues when switching back
-    // or if the session was updated from elsewhere
     try {
       const msgs = await ChatService.getMessages(id)
       setThreadMessages(prev => ({ ...prev, [id]: msgs }))
@@ -125,7 +153,6 @@ function App() {
     try {
       await ChatService.deleteConversation(id)
       setConversations(prev => prev.filter(c => c.id !== id))
-      // Also clear from cache
       setThreadMessages(prev => {
         const next = { ...prev }
         delete next[id]
@@ -202,7 +229,7 @@ function App() {
                 <div className="flex-1 min-h-0">
                   {selectedThreadId ? (
                     <ChatInterface 
-                      key={selectedThreadId} // Force remount on thread change
+                      key={selectedThreadId} 
                       threadId={selectedThreadId} 
                       initialMessages={threadMessages[selectedThreadId] || []}
                       onMessagesFinal={(msgs) => handleMessagesFinal(selectedThreadId, msgs)}
@@ -249,4 +276,23 @@ function App() {
   )
 }
 
+function ThemeWrapper({ children }: { children: React.ReactNode }) {
+  const { isAuthenticated } = useAuth()
+  return (
+    <ThemeProvider isAuthenticated={isAuthenticated}>
+      {children}
+    </ThemeProvider>
+  )
+}
+
+function App() {
+  return (
+    <AuthProvider>
+      <ThemeWrapper>
+        <AppContent />
+      </ThemeWrapper>
+    </AuthProvider>
+  )
+}
+
 export default App