Added Local Notification for Matches (Android Only)

android/app/build.gradle

@@ -27,10 +27,13 @@ if (flutterVersionName == null) {
 
 android {
     namespace "com.example.cofounderella"
-    compileSdk flutter.compileSdkVersion
+    compileSdk 34 // 34 required by flutter_local_notification; old value: flutter.compileSdkVersion
     ndkVersion "26.1.10909125"
 
     compileOptions {
+        // Flag to enable support for the new language APIs
+        coreLibraryDesugaringEnabled true
+        // Sets Java compatibility to Java 8
         sourceCompatibility JavaVersion.VERSION_1_8
         targetCompatibility JavaVersion.VERSION_1_8
     }
@@ -67,4 +70,10 @@ flutter {
     source '../..'
 }
 
-dependencies {}
+dependencies {
+    coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:2.0.3'
+    // There have been reports that enabling desugaring may result in a Flutter apps crashing on
+    // Android 12L and above. https://pub.dev/packages/flutter_local_notifications#-android-setup
+    implementation 'androidx.window:window:1.0.0'
+    implementation 'androidx.window:window-java:1.0.0'
+}

lib/main.dart

@@ -1,3 +1,4 @@
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import '../constants.dart';
 import '../services/auth/auth_gate.dart';
@@ -10,6 +11,7 @@ import 'pages/conversations_page.dart';
 import 'pages/liked_users_page.dart';
 import 'pages/user_matching_page.dart';
 import 'pages/user_profile_page.dart';
+import 'services/swipe_stream_service.dart';
 
 void main() async {
   // Firebase stuff
@@ -22,14 +24,35 @@ void main() async {
   final prefs = await SharedPreferences.getInstance();
   final isDarkMode = prefs.getBool(Constants.prefKeyThemeDarkMode) ?? false;
 
+  final FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin =
+      FlutterLocalNotificationsPlugin();
+  const AndroidInitializationSettings initializationSettingsAndroid =
+      AndroidInitializationSettings('@mipmap/ic_launcher');
+  const InitializationSettings initializationSettings =
+      InitializationSettings(android: initializationSettingsAndroid);
+  await flutterLocalNotificationsPlugin.initialize(initializationSettings);
+
+  // Initialize the singleton instance with a dummy userId.
+  // The actual userId is set later in the HomePage.
+  SwipeStreamService()
+      .initialize('dummy_initial_user_id', flutterLocalNotificationsPlugin);
+
   runApp(
+    MultiProvider(
+      providers: [
         ChangeNotifierProvider(
-      create: (context) => ThemeProvider(initialIsDarkMode: isDarkMode),
+            create: (context) => ThemeProvider(initialIsDarkMode: isDarkMode)),
+        Provider<FlutterLocalNotificationsPlugin>.value(
+            value: flutterLocalNotificationsPlugin),
+      ],
       child: const MyApp(),
     ),
   );
 }
 
+// Global key for navigation
+final GlobalKey<NavigatorState> navigatorKey = GlobalKey<NavigatorState>();
+
 class MyApp extends StatelessWidget {
   const MyApp({super.key});
 
@@ -39,6 +62,7 @@ class MyApp extends StatelessWidget {
       debugShowCheckedModeBanner: false,
       title: Constants.appTitle,
       theme: Provider.of<ThemeProvider>(context).themeData,
+      navigatorKey: navigatorKey,
       home: const AuthGate(),
       routes: {
         '/discover': (context) => const UserMatchingPage(),

lib/pages/home_page.dart

@@ -1,11 +1,23 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
+import 'package:provider/provider.dart';
 import '../components/my_drawer.dart';
+import '../services/auth/auth_service.dart';
+import '../services/swipe_stream_service.dart';
 
 class HomePage extends StatelessWidget {
   const HomePage({super.key});
 
   @override
   Widget build(BuildContext context) {
+    final currentUserId = AuthService().getCurrentUser()!.uid;
+    final flutterLocalNotificationsPlugin =
+        Provider.of<FlutterLocalNotificationsPlugin>(context);
+    final swipeStreamService = SwipeStreamService();
+    swipeStreamService.initialize(
+        currentUserId, flutterLocalNotificationsPlugin);
+    swipeStreamService.listenToSwipes();
+
     return Scaffold(
       appBar: AppBar(
         title: const Text('Home'),

lib/pages/user_matching_page.dart

@@ -12,6 +12,7 @@ import '../constants.dart';
 import '../forms/matched_screen.dart';
 import '../models/user_profile.dart';
 import '../services/auth/auth_service.dart';
+import '../services/swipe_stream_service.dart';
 import '../services/user_service.dart';
 import '../utils/helper.dart';
 import '../utils/list_utils.dart';
@@ -173,6 +174,9 @@ class UserMatchingPageState extends State<UserMatchingPage> {
           .doc(swipedUserId)
           .collection(Constants.dbCollectionMatches);
 
+      // current user swiped, so avoid local push notification
+      SwipeStreamService().addUser(swipedUserId);
+
       await matchesCurrentUser.doc(swipedUserId).set({
         'otherUserId': swipedUserId,
         'timestamp': FieldValue.serverTimestamp(),
@@ -183,9 +187,6 @@ class UserMatchingPageState extends State<UserMatchingPage> {
         'timestamp': FieldValue.serverTimestamp(),
       });
 
-      //
-      // TODO Notify other user?
-      //
       showMatchedScreen(currentUserId, swipedUserId);
 
       // Remove matched user from the list of potential users
@@ -237,9 +238,9 @@ class UserMatchingPageState extends State<UserMatchingPage> {
     } else if (percentage >= 40) {
       return Colors.amber.shade200; // 54 - 40
     } else if (percentage >= 20) {
-      return Colors.orange.shade200; // 39 - 20
+      return Colors.orange; // 39 - 20
     } else {
-      return Colors.orange.shade300; // 19 - 0
+      return Colors.red.shade400; // 19 - 0
     }
   }
 

lib/services/auth/auth_service.dart

@@ -1,5 +1,7 @@
 import 'package:firebase_auth/firebase_auth.dart';
 
+import '../swipe_stream_service.dart';
+
 class AuthService {
   // instance of auth
   final FirebaseAuth _auth = FirebaseAuth.instance;
@@ -45,6 +47,7 @@ class AuthService {
 
   // sign out
   Future<void> signOut() async {
+    SwipeStreamService().stopListening();
     await _auth.signOut();
   }
 }

lib/services/swipe_stream_service.dart

@@ -0,0 +1,122 @@
+import 'dart:async';
+import 'package:flutter/foundation.dart' show debugPrint, kDebugMode;
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
+import '../constants.dart';
+import '../main.dart';
+import '../utils/helper_dialogs.dart';
+import 'user_service.dart';
+
+class SwipeStreamService {
+  final FirebaseFirestore _firestore = FirebaseFirestore.instance;
+  final List<String> _matchesInDB = [];
+
+  StreamSubscription<List<DocumentSnapshot>>? _subscription;
+
+  late String userId;
+  late FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin;
+  late bool matchesRead = false;
+
+  // Singleton instance
+  static final SwipeStreamService _instance = SwipeStreamService._internal();
+
+  // Private constructor
+  SwipeStreamService._internal();
+
+  // Factory constructor
+  factory SwipeStreamService() {
+    return _instance;
+  }
+
+  // Initialization method
+  void initialize(String userId, FlutterLocalNotificationsPlugin plugin) {
+    _instance.userId = userId;
+    _instance.flutterLocalNotificationsPlugin = plugin;
+    // Reset old data
+    _matchesInDB.clear();
+    matchesRead = false;
+  }
+
+  Stream<List<DocumentSnapshot>> get swipesStream {
+    return _firestore
+        .collection(Constants.dbCollectionUsers)
+        .doc(userId)
+        .collection(Constants.dbCollectionMatches)
+        .snapshots()
+        .map((snapshot) => snapshot.docs);
+  }
+
+  void _showNotification(String swipeId) async {
+    String matchName = await UserService.getUserName(swipeId);
+    const AndroidNotificationDetails androidPlatformChannelSpecifics =
+        AndroidNotificationDetails(
+            'my_match_channel_id', 'my_match_channel_name',
+            channelShowBadge: true,
+            visibility: NotificationVisibility.private,
+            importance: Importance.max,
+            priority: Priority.high,
+            showWhen: true);
+    const NotificationDetails platformChannelSpecifics =
+        NotificationDetails(android: androidPlatformChannelSpecifics);
+    await flutterLocalNotificationsPlugin.show(0, 'New Match',
+        'You have a new match with $matchName', platformChannelSpecifics);
+  }
+
+  void listenToSwipes() {
+    _subscription = swipesStream.listen(
+      (swipes) async {
+        List<String> userNames = [];
+        String tempUser = '';
+
+        if (!matchesRead) {
+          for (var swipe in swipes) {
+            debugPrint('Init Match Notify --> ${swipe.id}');
+            _matchesInDB.add(swipe.id);
+            tempUser = await UserService.getUserName(swipe.id);
+            userNames.add('INIT $tempUser');
+          }
+          if (kDebugMode) {
+            showErrorSnackBar(
+              navigatorKey.currentContext!,
+              userNames.join(', '),
+            );
+          }
+
+          matchesRead = true;
+        } else {
+          for (var swipe in swipes) {
+            tempUser = await UserService.getUserName(swipe.id);
+
+            if (!_matchesInDB.contains(swipe.id)) {
+              userNames.add('NEW! $tempUser');
+              debugPrint('NEW Match Notify --> ${swipe.id}');
+              _matchesInDB.add(swipe.id);
+              _showNotification(swipe.id);
+            } else {
+              userNames.add('OLD $tempUser');
+              debugPrint('Old Match Notify --> ${swipe.id}');
+            }
+          }
+          if (kDebugMode) {
+            showErrorSnackBar(
+              navigatorKey.currentContext!,
+              userNames.join(', '),
+            );
+          }
+        }
+      },
+    );
+  }
+
+  void stopListening() {
+    _subscription?.cancel();
+    _subscription = null;
+  }
+
+  void addUser(String userId) {
+    if (!_matchesInDB.contains(userId)) {
+      debugPrint('Notify: SKIP Match Notify for --> $userId');
+      _matchesInDB.add(userId);
+    }
+  }
+}

lib/services/user_service.dart

@@ -346,4 +346,21 @@ class UserService {
       throw Exception('Error fetching sectors from Firebase: $e');
     }
   }
+
+  static Future<String> getUserName(String userId) async {
+    try {
+      DocumentSnapshot userDoc = await FirebaseFirestore.instance
+          .collection(Constants.dbCollectionUsers)
+          .doc(userId)
+          .get();
+
+      if (userDoc.exists) {
+        return userDoc[Constants.dbFieldUsersName] ?? 'Unknown User';
+      } else {
+        return 'User not found';
+      }
+    } catch (e) {
+      return e.toString();
+    }
+  }
 }

pubspec.lock

@@ -129,6 +129,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.8"
+  dbus:
+    dependency: transitive
+    description:
+      name: dbus
+      sha256: "365c771ac3b0e58845f39ec6deebc76e3276aa9922b0cc60840712094d9047ac"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.7.10"
   expandable_text:
     dependency: "direct main"
     description:
@@ -294,6 +302,30 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.0.2"
+  flutter_local_notifications:
+    dependency: "direct main"
+    description:
+      name: flutter_local_notifications
+      sha256: "40e6fbd2da7dcc7ed78432c5cdab1559674b4af035fddbfb2f9a8f9c2112fcef"
+      url: "https://pub.dev"
+    source: hosted
+    version: "17.1.2"
+  flutter_local_notifications_linux:
+    dependency: transitive
+    description:
+      name: flutter_local_notifications_linux
+      sha256: "33f741ef47b5f63cc7f78fe75eeeac7e19f171ff3c3df054d84c1e38bedb6a03"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.0.0+1"
+  flutter_local_notifications_platform_interface:
+    dependency: transitive
+    description:
+      name: flutter_local_notifications_platform_interface
+      sha256: "340abf67df238f7f0ef58f4a26d2a83e1ab74c77ab03cd2b2d5018ac64db30b7"
+      url: "https://pub.dev"
+    source: hosted
+    version: "7.1.0"
   flutter_plugin_android_lifecycle:
     dependency: transitive
     description:
@@ -821,6 +853,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.7.0"
+  timezone:
+    dependency: transitive
+    description:
+      name: timezone
+      sha256: a6ccda4a69a442098b602c44e61a1e2b4bf6f5516e875bbf0f427d5df14745d5
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.9.3"
   typed_data:
     dependency: transitive
     description:

pubspec.yaml

@@ -31,6 +31,7 @@ dependencies:
   shared_preferences: ^2.2.3
   flutter_launcher_icons: ^0.13.1
   url_launcher: ^6.3.0
+  flutter_local_notifications: ^17.1.2
 
 dev_dependencies:
   flutter_test: