feat: integrate flutter_local_notifications for enhanced voice call notifications

- Added flutter_local_notifications dependency to manage notifications during voice calls.
- Implemented notification handling in VoiceCallService to update call status and manage user interactions.
- Enabled wake lock functionality to keep the screen on during calls and prevent audio interruptions.
- Updated AndroidManifest.xml to include necessary permissions for Bluetooth and foreground services.
- Enhanced notification actions to allow users to mute, unmute, or end calls directly from notifications.

android/app/build.gradle.kts

@@ -31,6 +31,8 @@ android {
         // Align with modern Android Gradle Plugin requirements
         sourceCompatibility = JavaVersion.VERSION_17
         targetCompatibility = JavaVersion.VERSION_17
+        // Enable core library desugaring for flutter_local_notifications
+        isCoreLibraryDesugaringEnabled = true
     }
 
     kotlinOptions {
@@ -73,6 +75,9 @@ dependencies {
     implementation("androidx.activity:activity:1.9.2")
     implementation("androidx.core:core:1.13.1")
     implementation("androidx.activity:activity-ktx:1.9.2")
+
+    // Core library desugaring for flutter_local_notifications
+    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs:2.1.4")
 }
 
 flutter {

android/app/src/main/AndroidManifest.xml

@@ -5,10 +5,14 @@
     <uses-permission android:name="android.permission.CAMERA"/>
     <!-- No broad media/storage permissions; use Android Photo Picker (API 33+) and SAF/share intents -->
 
+    <!-- Bluetooth permissions for audio routing (Android 12+) -->
+    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" android:maxSdkVersion="32" />
+
     <!-- Background streaming permissions -->
     <uses-permission android:name="android.permission.WAKE_LOCK"/>
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE_DATA_SYNC"/>
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MICROPHONE"/>
     <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
     
     <queries>
@@ -88,7 +92,7 @@
             android:name=".BackgroundStreamingService"
             android:enabled="true"
             android:exported="false"
-            android:foregroundServiceType="dataSync"/>
+            android:foregroundServiceType="dataSync|microphone"/>
         
         <!-- Don't delete the meta-data below.
              This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->

android/app/src/main/res/drawable/ic_call_end.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M12,9c-1.6,0 -3.15,0.25 -4.6,0.72v3.1c0,0.39 -0.23,0.74 -0.56,0.9 -0.98,0.49 -1.87,1.12 -2.66,1.85 -0.18,0.18 -0.43,0.28 -0.7,0.28 -0.28,0 -0.53,-0.11 -0.71,-0.29L0.29,13.08c-0.18,-0.17 -0.29,-0.42 -0.29,-0.7 0,-0.28 0.11,-0.53 0.29,-0.71C3.34,8.78 7.46,7 12,7s8.66,1.78 11.71,4.67c0.18,0.18 0.29,0.43 0.29,0.71 0,0.28 -0.11,0.53 -0.29,0.71l-2.48,2.48c-0.18,0.18 -0.43,0.29 -0.71,0.29 -0.27,0 -0.52,-0.11 -0.7,-0.28 -0.79,-0.74 -1.69,-1.36 -2.67,-1.85 -0.33,-0.16 -0.56,-0.5 -0.56,-0.9v-3.1C15.15,9.25 13.6,9 12,9z"/>
+</vector>

android/app/src/main/res/drawable/ic_mic_off.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M19,11h-1.7c0,0.74 -0.16,1.43 -0.43,2.05l1.23,1.23c0.56,-0.98 0.9,-2.09 0.9,-3.28zM14.98,11.17c0,-0.06 0.02,-0.11 0.02,-0.17L15,5c0,-1.66 -1.34,-3 -3,-3S9,3.34 9,5v0.18l5.98,5.99zM4.27,3L3,4.27l6.01,6.01L9.01,11c0,1.66 1.33,3 2.99,3 0.22,0 0.44,-0.03 0.65,-0.08l1.66,1.66c-0.71,0.33 -1.5,0.52 -2.31,0.52 -2.76,0 -5.3,-2.1 -5.3,-5.1L5,11c0,3.41 2.72,6.23 6,6.72L11,21h2v-3.28c0.91,-0.13 1.77,-0.45 2.54,-0.9L19.73,21 21,19.73 4.27,3z"/>
+</vector>

android/app/src/main/res/drawable/ic_mic_on.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M12,14c1.66,0 2.99,-1.34 2.99,-3L15,5c0,-1.66 -1.34,-3 -3,-3S9,3.34 9,5v6c0,1.66 1.34,3 3,3zM17.3,11c0,3 -2.54,5.1 -5.3,5.1S6.7,14 6.7,11L5,11c0,3.41 2.72,6.23 6,6.72L11,21h2v-3.28c3.28,-0.48 6,-3.3 6,-6.72h-1.7z"/>
+</vector>

lib/features/chat/services/voice_call_notification_service.dart

@@ -0,0 +1,225 @@
+import 'dart:io';
+
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
+
+/// Service to manage persistent notifications for voice calls
+class VoiceCallNotificationService {
+  static final VoiceCallNotificationService _instance =
+      VoiceCallNotificationService._internal();
+  factory VoiceCallNotificationService() => _instance;
+  VoiceCallNotificationService._internal();
+
+  final FlutterLocalNotificationsPlugin _notifications =
+      FlutterLocalNotificationsPlugin();
+
+  bool _initialized = false;
+
+  // Notification IDs and channels
+  static const String _channelId = 'voice_call_channel';
+  static const String _channelName = 'Voice Call';
+  static const String _channelDescription =
+      'Ongoing voice call notifications';
+  static const int _notificationId = 2001;
+
+  // Action IDs
+  static const String _actionMute = 'mute_call';
+  static const String _actionUnmute = 'unmute_call';
+  static const String _actionEndCall = 'end_call';
+
+  // Callback for handling notification actions
+  void Function(String action)? onActionPressed;
+
+  Future<void> initialize() async {
+    if (_initialized) return;
+
+    const androidSettings = AndroidInitializationSettings('@mipmap/ic_launcher');
+    const iosSettings = DarwinInitializationSettings(
+      requestAlertPermission: false,
+      requestBadgePermission: false,
+      requestSoundPermission: false,
+    );
+
+    const settings = InitializationSettings(
+      android: androidSettings,
+      iOS: iosSettings,
+    );
+
+    await _notifications.initialize(
+      settings,
+      onDidReceiveNotificationResponse: _handleNotificationResponse,
+      onDidReceiveBackgroundNotificationResponse:
+          _handleBackgroundNotificationResponse,
+    );
+
+    // Create notification channel for Android
+    if (Platform.isAndroid) {
+      await _createAndroidNotificationChannel();
+    }
+
+    _initialized = true;
+  }
+
+  Future<void> _createAndroidNotificationChannel() async {
+    const androidChannel = AndroidNotificationChannel(
+      _channelId,
+      _channelName,
+      description: _channelDescription,
+      importance: Importance.high,
+      playSound: false,
+      enableVibration: false,
+      showBadge: false,
+    );
+
+    await _notifications
+        .resolvePlatformSpecificImplementation<
+            AndroidFlutterLocalNotificationsPlugin>()
+        ?.createNotificationChannel(androidChannel);
+  }
+
+  void _handleNotificationResponse(NotificationResponse response) {
+    final action = response.actionId;
+    if (action != null && onActionPressed != null) {
+      onActionPressed!(action);
+    }
+  }
+
+  @pragma('vm:entry-point')
+  static void _handleBackgroundNotificationResponse(
+    NotificationResponse response,
+  ) {
+    // Background action handling
+    // Note: This runs in an isolate, so we can't directly call instance methods
+    // Actions will be handled when app returns to foreground
+  }
+
+  /// Show ongoing voice call notification
+  Future<void> showCallNotification({
+    required String modelName,
+    required bool isMuted,
+    required bool isSpeaking,
+  }) async {
+    if (!_initialized) {
+      print('VoiceCallNotification: Initializing...');
+      await initialize();
+    }
+
+    print('VoiceCallNotification: Showing notification for $modelName (muted: $isMuted, speaking: $isSpeaking)');
+
+    final status = isSpeaking ? 'Speaking...' : 'Listening...';
+    final muteAction = isMuted ? 'Unmute' : 'Mute';
+    final muteActionId = isMuted ? _actionUnmute : _actionMute;
+
+    if (Platform.isAndroid) {
+      final androidDetails = AndroidNotificationDetails(
+        _channelId,
+        _channelName,
+        channelDescription: _channelDescription,
+        importance: Importance.high,
+        priority: Priority.high,
+        ongoing: true,
+        autoCancel: false,
+        playSound: false,
+        enableVibration: false,
+        showWhen: true,
+        usesChronometer: true,
+        chronometerCountDown: false,
+        category: AndroidNotificationCategory.call,
+        visibility: NotificationVisibility.public,
+        icon: '@mipmap/ic_launcher',
+        colorized: false,
+        actions: <AndroidNotificationAction>[
+          AndroidNotificationAction(
+            muteActionId,
+            muteAction,
+            icon: DrawableResourceAndroidBitmap(
+              isMuted ? '@drawable/ic_mic_on' : '@drawable/ic_mic_off',
+            ),
+            showsUserInterface: false,
+            cancelNotification: false,
+          ),
+          AndroidNotificationAction(
+            _actionEndCall,
+            'End Call',
+            icon: DrawableResourceAndroidBitmap('@drawable/ic_call_end'),
+            showsUserInterface: true,
+            cancelNotification: true,
+          ),
+        ],
+      );
+
+      await _notifications.show(
+        _notificationId,
+        'Voice Call with $modelName',
+        status,
+        NotificationDetails(android: androidDetails),
+      );
+    } else if (Platform.isIOS) {
+      // iOS doesn't support action buttons for ongoing notifications
+      // Use a simpler persistent notification
+      const iosDetails = DarwinNotificationDetails(
+        presentAlert: true,
+        presentBadge: false,
+        presentSound: false,
+        interruptionLevel: InterruptionLevel.timeSensitive,
+      );
+
+      await _notifications.show(
+        _notificationId,
+        'Voice Call with $modelName',
+        status,
+        const NotificationDetails(iOS: iosDetails),
+      );
+    }
+  }
+
+  /// Update notification status
+  Future<void> updateCallStatus({
+    required String modelName,
+    required bool isMuted,
+    required bool isSpeaking,
+  }) async {
+    await showCallNotification(
+      modelName: modelName,
+      isMuted: isMuted,
+      isSpeaking: isSpeaking,
+    );
+  }
+
+  /// Cancel the voice call notification
+  Future<void> cancelNotification() async {
+    await _notifications.cancel(_notificationId);
+  }
+
+  /// Check if notifications are enabled
+  Future<bool> areNotificationsEnabled() async {
+    if (Platform.isAndroid) {
+      final androidImpl = _notifications.resolvePlatformSpecificImplementation<
+          AndroidFlutterLocalNotificationsPlugin>();
+      return await androidImpl?.areNotificationsEnabled() ?? false;
+    } else if (Platform.isIOS) {
+      // iOS doesn't have a direct check, assume enabled if initialized
+      return _initialized;
+    }
+    return false;
+  }
+
+  /// Request notification permissions
+  Future<bool> requestPermissions() async {
+    if (Platform.isAndroid) {
+      final androidImpl = _notifications.resolvePlatformSpecificImplementation<
+          AndroidFlutterLocalNotificationsPlugin>();
+      final granted = await androidImpl?.requestNotificationsPermission();
+      return granted ?? false;
+    } else if (Platform.isIOS) {
+      final iosImpl = _notifications
+          .resolvePlatformSpecificImplementation<IOSFlutterLocalNotificationsPlugin>();
+      final granted = await iosImpl?.requestPermissions(
+        alert: true,
+        badge: false,
+        sound: false,
+      );
+      return granted ?? false;
+    }
+    return false;
+  }
+}

lib/features/chat/services/voice_call_service.dart

@@ -1,12 +1,14 @@
 import 'dart:async';
 
 import 'package:riverpod_annotation/riverpod_annotation.dart';
+import 'package:wakelock_plus/wakelock_plus.dart';
 
 import '../../../core/providers/app_providers.dart';
 import '../../../core/services/socket_service.dart';
 import '../providers/chat_providers.dart';
 import 'text_to_speech_service.dart';
 import 'voice_input_service.dart';
+import 'voice_call_notification_service.dart';
 
 part 'voice_call_service.g.dart';
 
@@ -25,13 +27,17 @@ class VoiceCallService {
   final TextToSpeechService _tts;
   final SocketService _socketService;
   final Ref _ref;
+  final VoiceCallNotificationService _notificationService =
+      VoiceCallNotificationService();
 
   VoiceCallState _state = VoiceCallState.idle;
   String? _sessionId;
+  String? _activeConversationId;
   StreamSubscription<String>? _transcriptSubscription;
   StreamSubscription<int>? _intensitySubscription;
   String _accumulatedTranscript = '';
   bool _isDisposed = false;
+  bool _isMuted = false;
   SocketEventSubscription? _socketSubscription;
 
   final StreamController<VoiceCallState> _stateController =
@@ -57,6 +63,9 @@ class VoiceCallService {
       onComplete: _handleTtsComplete,
       onError: _handleTtsError,
     );
+
+    // Set up notification action handler
+    _notificationService.onActionPressed = _handleNotificationAction;
   }
 
   VoiceCallState get state => _state;
@@ -68,6 +77,16 @@ class VoiceCallService {
   Future<void> initialize() async {
     if (_isDisposed) return;
 
+    // Initialize notification service
+    await _notificationService.initialize();
+
+    // Request notification permissions if needed
+    final notificationsEnabled =
+        await _notificationService.areNotificationsEnabled();
+    if (!notificationsEnabled) {
+      await _notificationService.requestPermissions();
+    }
+
     // Initialize voice input
     final voiceInitialized = await _voiceInput.initialize();
     if (!voiceInitialized) {
@@ -97,8 +116,15 @@ class VoiceCallService {
     if (_isDisposed) return;
 
     try {
+      // Set conversation ID first before updating state
+      _activeConversationId = conversationId;
+
+      // Update state (this will trigger notification)
       _updateState(VoiceCallState.connecting);
 
+      // Enable wake lock to keep screen on and prevent audio interruption
+      await WakelockPlus.enable();
+
       // Ensure socket connection
       await _socketService.ensureConnected();
       _sessionId = _socketService.sessionId;
@@ -119,6 +145,8 @@ class VoiceCallService {
       await _startListening();
     } catch (e) {
       _updateState(VoiceCallState.error);
+      await WakelockPlus.disable();
+      await _notificationService.cancelNotification();
       rethrow;
     }
   }
@@ -298,8 +326,16 @@ class VoiceCallService {
     await _voiceInput.stopListening();
     await _tts.stop();
 
+    // Cancel notification
+    await _notificationService.cancelNotification();
+
+    // Disable wake lock when call ends
+    await WakelockPlus.disable();
+
     _sessionId = null;
+    _activeConversationId = null;
     _accumulatedTranscript = '';
+    _isMuted = false;
     _updateState(VoiceCallState.disconnected);
   }
 
@@ -326,6 +362,60 @@ class VoiceCallService {
     if (_isDisposed) return;
     _state = newState;
     _stateController.add(newState);
+
+    // Update notification when state changes (fire and forget)
+    _updateNotification().catchError((e) {
+      // Ignore notification errors
+    });
+  }
+
+  Future<void> _updateNotification() async {
+    // Skip notification for idle, error, and disconnected states
+    if (_state == VoiceCallState.idle ||
+        _state == VoiceCallState.error ||
+        _state == VoiceCallState.disconnected) {
+      print('VoiceCall: Skipping notification - state: $_state');
+      return;
+    }
+
+    try {
+      final selectedModel = _ref.read(selectedModelProvider);
+      final modelName = selectedModel?.name ?? 'Assistant';
+
+      print('VoiceCall: Updating notification - model: $modelName, muted: $_isMuted, state: $_state');
+
+      await _notificationService.updateCallStatus(
+        modelName: modelName,
+        isMuted: _isMuted,
+        isSpeaking: _state == VoiceCallState.speaking,
+      );
+    } catch (e) {
+      print('VoiceCall: Failed to update notification: $e');
+    }
+  }
+
+  void _handleNotificationAction(String action) {
+    switch (action) {
+      case 'mute_call':
+        _toggleMute();
+        break;
+      case 'unmute_call':
+        _toggleMute();
+        break;
+      case 'end_call':
+        stopCall();
+        break;
+    }
+  }
+
+  void _toggleMute() {
+    _isMuted = !_isMuted;
+    if (_isMuted) {
+      pauseListening();
+    } else {
+      resumeListening();
+    }
+    _updateNotification();
   }
 
   Future<void> dispose() async {
@@ -338,6 +428,12 @@ class VoiceCallService {
     _voiceInput.dispose();
     await _tts.dispose();
 
+    // Cancel notification
+    await _notificationService.cancelNotification();
+
+    // Ensure wake lock is disabled on dispose
+    await WakelockPlus.disable();
+
     await _stateController.close();
     await _transcriptController.close();
     await _responseController.close();

pubspec.lock

@@ -438,6 +438,38 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "6.0.0"
+  flutter_local_notifications:
+    dependency: "direct main"
+    description:
+      name: flutter_local_notifications
+      sha256: "7ed76be64e8a7d01dfdf250b8434618e2a028c9dfa2a3c41dc9b531d4b3fc8a5"
+      url: "https://pub.dev"
+    source: hosted
+    version: "19.4.2"
+  flutter_local_notifications_linux:
+    dependency: transitive
+    description:
+      name: flutter_local_notifications_linux
+      sha256: e3c277b2daab8e36ac5a6820536668d07e83851aeeb79c446e525a70710770a5
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.0.0"
+  flutter_local_notifications_platform_interface:
+    dependency: transitive
+    description:
+      name: flutter_local_notifications_platform_interface
+      sha256: "277d25d960c15674ce78ca97f57d0bae2ee401c844b6ac80fcd972a9c99d09fe"
+      url: "https://pub.dev"
+    source: hosted
+    version: "9.1.0"
+  flutter_local_notifications_windows:
+    dependency: transitive
+    description:
+      name: flutter_local_notifications_windows
+      sha256: "8d658f0d367c48bd420e7cf2d26655e2d1130147bca1eea917e576ca76668aaf"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.3"
   flutter_localizations:
     dependency: "direct main"
     description: flutter
@@ -1514,6 +1546,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.6.11"
+  timezone:
+    dependency: transitive
+    description:
+      name: timezone
+      sha256: dd14a3b83cfd7cb19e7888f1cbc20f258b8d71b54c06f79ac585f14093a287d1
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.10.1"
   timing:
     dependency: transitive
     description:

pubspec.yaml

@@ -67,6 +67,7 @@ dependencies:
   share_plus: ^12.0.0
   share_handler: ^0.0.19
   riverpod_annotation: ^3.0.0
+  flutter_local_notifications: ^19.4.2
   
   # Clipboard functionality is available through flutter/services (part of Flutter SDK)