feat: add Firebase Analytics and make Google Maps Flutter dependencies direct.

backend/Program.cs

@@ -169,10 +169,180 @@ app.MapGet("/api/metrics/general", async (
         Console.WriteLine($"Error: {ex}");
         return Results.Problem($"Analytics API Error: {ex.Message}");
     }
+
 })
 .WithName("GetGeneralMetrics")
 .WithOpenApi();
 
+    // 3. Tech Overview (OS & App Version)
+    // GET /api/metrics/tech?from=x&to=y
+    app.MapGet("/api/metrics/tech", async (
+        [FromServices] AnalyticsDataService service,
+        [FromQuery] string? from, 
+        [FromQuery] string? to) =>
+    {
+        var startDate = from ?? "30daysAgo";
+        var endDate = to ?? "today";
+
+        // Request for OS
+        var requestOS = new RunReportRequest
+        {
+            Property = $"properties/{ga4PropertyId}",
+            DateRanges = new List<DateRange> { new DateRange { StartDate = startDate, EndDate = endDate } },
+            Dimensions = new List<Dimension> { new Dimension { Name = "operatingSystem" } },
+            Metrics = new List<Metric> { new Metric { Name = "activeUsers" } }
+        };
+
+        // Request for App Version
+        var requestVersion = new RunReportRequest
+        {
+            Property = $"properties/{ga4PropertyId}",
+            DateRanges = new List<DateRange> { new DateRange { StartDate = startDate, EndDate = endDate } },
+            Dimensions = new List<Dimension> { new Dimension { Name = "appVersion" } },
+            Metrics = new List<Metric> { new Metric { Name = "activeUsers" } } // use active users to see version adoption
+        };
+
+        try
+        {
+            var responseOS = await service.Properties.RunReport(requestOS, $"properties/{ga4PropertyId}").ExecuteAsync();
+            var responseVersion = await service.Properties.RunReport(requestVersion, $"properties/{ga4PropertyId}").ExecuteAsync();
+
+            var osData = responseOS.Rows?.Select(row => new { 
+                os = row.DimensionValues[0].Value, 
+                users = int.Parse(row.MetricValues[0].Value) 
+            }) ?? Enumerable.Empty<object>();
+
+            var versionData = responseVersion.Rows?.Select(row => new { 
+                version = row.DimensionValues[0].Value, 
+                users = int.Parse(row.MetricValues[0].Value) 
+            }) ?? Enumerable.Empty<object>();
+
+            return Results.Ok(new { operatingSystems = osData, appVersions = versionData });
+        }
+        catch (Exception ex)
+        {
+             return Results.Problem($"Analytics API Error: {ex.Message}");
+        }
+    })
+    .WithName("GetTechOverview")
+    .WithOpenApi();
+
+    // 4. Top Events
+    // GET /api/metrics/events?from=x&to=y
+    app.MapGet("/api/metrics/events", async (
+        [FromServices] AnalyticsDataService service,
+        [FromQuery] string? from, 
+        [FromQuery] string? to) =>
+    {
+        var startDate = from ?? "30daysAgo";
+        var endDate = to ?? "today";
+
+        var request = new RunReportRequest
+        {
+            Property = $"properties/{ga4PropertyId}",
+            DateRanges = new List<DateRange> { new DateRange { StartDate = startDate, EndDate = endDate } },
+            Dimensions = new List<Dimension> { new Dimension { Name = "eventName" } },
+            Metrics = new List<Metric> { new Metric { Name = "eventCount" }, new Metric { Name = "activeUsers" } },
+            OrderBys = new List<OrderBy> { new OrderBy { Desc = true, Metric = new MetricOrderBy { MetricName = "eventCount" } } },
+            Limit = 20
+        };
+
+        try
+        {
+            var response = await service.Properties.RunReport(request, $"properties/{ga4PropertyId}").ExecuteAsync();
+            var result = response.Rows?.Select(row => new { 
+                eventName = row.DimensionValues[0].Value, 
+                count = int.Parse(row.MetricValues[0].Value),
+                users = int.Parse(row.MetricValues[1].Value)
+            }) ?? Enumerable.Empty<object>();
+
+            return Results.Ok(result);
+        }
+         catch (Exception ex)
+        {
+             return Results.Problem($"Analytics API Error: {ex.Message}");
+        }
+    })
+    .WithName("GetTopEvents")
+    .WithOpenApi();
+
+    // 5. Top Screens
+    // GET /api/metrics/screens?from=x&to=y
+    app.MapGet("/api/metrics/screens", async (
+        [FromServices] AnalyticsDataService service,
+        [FromQuery] string? from, 
+        [FromQuery] string? to) =>
+    {
+        var startDate = from ?? "30daysAgo";
+        var endDate = to ?? "today";
+
+        var request = new RunReportRequest
+        {
+            Property = $"properties/{ga4PropertyId}",
+            DateRanges = new List<DateRange> { new DateRange { StartDate = startDate, EndDate = endDate } },
+            // GA4 uses 'unifiedScreenName' or 'pagePath' depending on setup, usually 'unifiedScreenName' for apps
+            Dimensions = new List<Dimension> { new Dimension { Name = "unifiedScreenName" } }, 
+            Metrics = new List<Metric> { new Metric { Name = "screenPageViews" }, new Metric { Name = "activeUsers" } },
+            OrderBys = new List<OrderBy> { new OrderBy { Desc = true, Metric = new MetricOrderBy { MetricName = "screenPageViews" } } },
+            Limit = 20
+        };
+
+        try
+        {
+            var response = await service.Properties.RunReport(request, $"properties/{ga4PropertyId}").ExecuteAsync();
+            var result = response.Rows?.Select(row => new { 
+                screenName = row.DimensionValues[0].Value, 
+                views = int.Parse(row.MetricValues[0].Value),
+                users = int.Parse(row.MetricValues[1].Value)
+            }) ?? Enumerable.Empty<object>();
+
+            return Results.Ok(result);
+        }
+         catch (Exception ex)
+        {
+             return Results.Problem($"Analytics API Error: {ex.Message}");
+        }
+    })
+    .WithName("GetTopScreens")
+    .WithOpenApi();
+
+    // 6. User Retention (New vs Returning)
+    // GET /api/metrics/retention?from=x&to=y
+    app.MapGet("/api/metrics/retention", async (
+        [FromServices] AnalyticsDataService service,
+        [FromQuery] string? from, 
+        [FromQuery] string? to) =>
+    {
+        var startDate = from ?? "30daysAgo";
+        var endDate = to ?? "today";
+
+        var request = new RunReportRequest
+        {
+            Property = $"properties/{ga4PropertyId}",
+            DateRanges = new List<DateRange> { new DateRange { StartDate = startDate, EndDate = endDate } },
+            Dimensions = new List<Dimension> { new Dimension { Name = "newVsReturning" } }, 
+            Metrics = new List<Metric> { new Metric { Name = "activeUsers" }, new Metric { Name = "sessions" } }
+        };
+
+        try
+        {
+            var response = await service.Properties.RunReport(request, $"properties/{ga4PropertyId}").ExecuteAsync();
+            var result = response.Rows?.Select(row => new { 
+                type = row.DimensionValues[0].Value, 
+                users = int.Parse(row.MetricValues[0].Value),
+                sessions = int.Parse(row.MetricValues[1].Value)
+            }) ?? Enumerable.Empty<object>();
+
+            return Results.Ok(result);
+        }
+        catch (Exception ex)
+        {
+             return Results.Problem($"Analytics API Error: {ex.Message}");
+        }
+    })
+    .WithName("GetUserRetention")
+    .WithOpenApi();
+
 app.Run();
 
 // Helper to format GA4 YYYYMMDD to YYYY-MM-DD

lib/blocs/auth/auth_bloc.dart

@@ -26,12 +26,14 @@ import '../../repositories/auth_repository.dart';
 import 'auth_event.dart';
 import 'auth_state.dart';
 import '../../services/notification_service.dart';
+import '../../services/analytics_service.dart';
 
 /// BLoC for managing authentication state and operations.
 class AuthBloc extends Bloc<AuthEvent, AuthState> {
   /// Repository for authentication operations.
   final AuthRepository _authRepository;
   final NotificationService _notificationService;
+  final AnalyticsService _analyticsService;
 
   /// Creates an [AuthBloc] with the provided [authRepository].
   ///
@@ -40,8 +42,10 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
   AuthBloc({
     required AuthRepository authRepository,
     NotificationService? notificationService,
+    AnalyticsService? analyticsService,
   }) : _authRepository = authRepository,
        _notificationService = notificationService ?? NotificationService(),
+       _analyticsService = analyticsService ?? AnalyticsService(),
        super(AuthInitial()) {
     on<AuthCheckRequested>(_onAuthCheckRequested);
     on<AuthSignInRequested>(_onSignInRequested);
@@ -76,6 +80,7 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
         if (user != null) {
           // Save FCM Token on auto-login
           await _notificationService.saveTokenToFirestore(user.id!);
+          await _analyticsService.setUserId(user.id);
           emit(AuthAuthenticated(user: user));
         } else {
           emit(AuthUnauthenticated());
@@ -107,6 +112,11 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
       if (user != null) {
         // Save FCM Token
         await NotificationService().saveTokenToFirestore(user.id!);
+        await _analyticsService.setUserId(user.id);
+        await _analyticsService.logEvent(
+          name: 'login',
+          parameters: {'method': 'email'},
+        );
         emit(AuthAuthenticated(user: user));
       } else {
         emit(const AuthError(message: 'Invalid email or password'));
@@ -138,6 +148,11 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
       if (user != null) {
         // Save FCM Token
         await NotificationService().saveTokenToFirestore(user.id!);
+        await _analyticsService.setUserId(user.id);
+        await _analyticsService.logEvent(
+          name: 'sign_up',
+          parameters: {'method': 'email'},
+        );
         emit(AuthAuthenticated(user: user));
       } else {
         emit(const AuthError(message: 'Failed to create account'));
@@ -163,6 +178,11 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
       if (user != null) {
         // Save FCM Token
         await NotificationService().saveTokenToFirestore(user.id!);
+        await _analyticsService.setUserId(user.id);
+        await _analyticsService.logEvent(
+          name: 'login',
+          parameters: {'method': 'google'},
+        );
         emit(AuthAuthenticated(user: user));
       } else {
         emit(
@@ -191,6 +211,11 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
       );
 
       if (user != null) {
+        await _analyticsService.setUserId(user.id);
+        await _analyticsService.logEvent(
+          name: 'sign_up',
+          parameters: {'method': 'google'},
+        );
         emit(AuthAuthenticated(user: user));
       } else {
         emit(const AuthError(message: 'Failed to create account with Google'));
@@ -214,6 +239,11 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
       );
 
       if (user != null) {
+        await _analyticsService.setUserId(user.id);
+        await _analyticsService.logEvent(
+          name: 'sign_up',
+          parameters: {'method': 'apple'},
+        );
         emit(AuthAuthenticated(user: user));
       } else {
         emit(const AuthError(message: 'Failed to create account with Apple'));
@@ -239,6 +269,11 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
       if (user != null) {
         // Save FCM Token
         await NotificationService().saveTokenToFirestore(user.id!);
+        await _analyticsService.setUserId(user.id);
+        await _analyticsService.logEvent(
+          name: 'login',
+          parameters: {'method': 'apple'},
+        );
         emit(AuthAuthenticated(user: user));
       } else {
         emit(
@@ -261,6 +296,7 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
     Emitter<AuthState> emit,
   ) async {
     await _authRepository.signOut();
+    await _analyticsService.setUserId(null); // Clear user ID
     emit(AuthUnauthenticated());
   }
 

lib/main.dart

@@ -17,6 +17,7 @@ import 'package:travel_mate/services/expense_service.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 import 'package:travel_mate/services/notification_service.dart';
 import 'package:travel_mate/services/map_navigation_service.dart';
+import 'package:travel_mate/services/analytics_service.dart';
 import 'blocs/auth/auth_bloc.dart';
 import 'blocs/auth/auth_event.dart';
 import 'blocs/theme/theme_bloc.dart';
@@ -146,6 +147,10 @@ class MyApp extends StatelessWidget {
         RepositoryProvider<MapNavigationService>(
           create: (context) => MapNavigationService(),
         ),
+        // Analysis service
+        RepositoryProvider<AnalyticsService>(
+          create: (context) => AnalyticsService(),
+        ),
       ],
       child: MultiBlocProvider(
         providers: [
@@ -206,6 +211,9 @@ class MyApp extends StatelessWidget {
               title: 'Travel Mate',
               navigatorKey: ErrorService.navigatorKey,
               themeMode: themeState.themeMode,
+              navigatorObservers: [
+                context.read<AnalyticsService>().getAnalyticsObserver(),
+              ],
               // Light theme configuration
               theme: ThemeData(
                 colorScheme: ColorScheme.fromSeed(

lib/services/analytics_service.dart

@@ -0,0 +1,54 @@
+import 'package:firebase_analytics/firebase_analytics.dart';
+import 'package:flutter/foundation.dart';
+
+/// Service wrapper for Google Analytics
+class AnalyticsService {
+  final FirebaseAnalytics _analytics = FirebaseAnalytics.instance;
+
+  FirebaseAnalyticsObserver getAnalyticsObserver() =>
+      FirebaseAnalyticsObserver(analytics: _analytics);
+
+  Future<void> logEvent({
+    required String name,
+    Map<String, Object>? parameters,
+  }) async {
+    try {
+      await _analytics.logEvent(name: name, parameters: parameters);
+    } catch (e) {
+      debugPrint('Error logging analytics event: $e');
+    }
+  }
+
+  Future<void> setUserProperty({
+    required String name,
+    required String? value,
+  }) async {
+    try {
+      await _analytics.setUserProperty(name: name, value: value);
+    } catch (e) {
+      debugPrint('Error setting user property: $e');
+    }
+  }
+
+  Future<void> setUserId(String? id) async {
+    try {
+      await _analytics.setUserId(id: id);
+    } catch (e) {
+      debugPrint('Error setting user ID: $e');
+    }
+  }
+
+  Future<void> logScreenView({
+    required String screenName,
+    String? screenClass,
+  }) async {
+    try {
+      await _analytics.logScreenView(
+        screenName: screenName,
+        screenClass: screenClass,
+      );
+    } catch (e) {
+      debugPrint('Error logging screen view: $e');
+    }
+  }
+}

pubspec.lock

@@ -13,10 +13,10 @@ packages:
     dependency: transitive
     description:
       name: _flutterfire_internals
-      sha256: "8a1f5f3020ef2a74fb93f7ab3ef127a8feea33a7a2276279113660784ee7516a"
+      sha256: e4a1b612fd2955908e26116075b3a4baf10c353418ca645b4deae231c82bf144
       url: "https://pub.dev"
     source: hosted
-    version: "1.3.64"
+    version: "1.3.65"
   analyzer:
     dependency: transitive
     description:
@@ -401,6 +401,30 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.9.3+4"
+  firebase_analytics:
+    dependency: "direct main"
+    description:
+      name: firebase_analytics
+      sha256: "8ca4832c7a6d145ce987fd07d6dfbb8c91d9058178342f20de6305fb77b1b40d"
+      url: "https://pub.dev"
+    source: hosted
+    version: "12.1.0"
+  firebase_analytics_platform_interface:
+    dependency: transitive
+    description:
+      name: firebase_analytics_platform_interface
+      sha256: d00234716f415f89eb5c2cefb1238d7fd2f3120275d71414b84ae434dcdb7a19
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.0.5"
+  firebase_analytics_web:
+    dependency: transitive
+    description:
+      name: firebase_analytics_web
+      sha256: e42b294e51aedb4bd4b761a886c8d6b473c44b44aa4c0b47cab06b2c66ac3fba
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.6.1+1"
   firebase_auth:
     dependency: "direct main"
     description:
@@ -429,10 +453,10 @@ packages:
     dependency: "direct main"
     description:
       name: firebase_core
-      sha256: "1f2dfd9f535d81f8b06d7a50ecda6eac1e6922191ed42e09ca2c84bd2288927c"
+      sha256: "29cfa93c771d8105484acac340b5ea0835be371672c91405a300303986f4eba9"
       url: "https://pub.dev"
     source: hosted
-    version: "4.2.1"
+    version: "4.3.0"
   firebase_core_platform_interface:
     dependency: transitive
     description:
@@ -445,10 +469,10 @@ packages:
     dependency: transitive
     description:
       name: firebase_core_web
-      sha256: ff18fabb0ad0ed3595d2f2c85007ecc794aadecdff5b3bb1460b7ee47cded398
+      sha256: a631bbfbfa26963d68046aed949df80b228964020e9155b086eff94f462bbf1f
       url: "https://pub.dev"
     source: hosted
-    version: "3.3.0"
+    version: "3.3.1"
   firebase_messaging:
     dependency: "direct main"
     description:

pubspec.yaml

@@ -66,6 +66,7 @@ dependencies:
   package_info_plus: ^8.3.1
   google_maps_flutter_platform_interface: ^2.14.1
   google_maps_flutter_android: ^2.18.6
+  firebase_analytics: ^12.1.0
 
 dev_dependencies:
   flutter_launcher_icons: ^0.13.1