refactor: decouple UserRepository Google auth contract

lib/core/services/google_authentication_service.dart

@@ -0,0 +1,101 @@
+import 'package:flutter/foundation.dart';
+import 'package:google_sign_in/google_sign_in.dart';
+import 'package:injectable/injectable.dart';
+import 'package:on_time_front/core/logging/app_logger.dart';
+import 'package:on_time_front/domain/entities/google_auth_credential.dart';
+
+abstract interface class GoogleAuthenticationService {
+  Stream<GoogleAuthCredential> get authenticationCredentials;
+
+  bool get supportsAuthenticate;
+
+  Future<void> initialize();
+
+  Future<GoogleAuthCredential> authenticate();
+
+  Future<void> disconnect();
+}
+
+class GoogleAuthenticationCanceledException implements Exception {
+  const GoogleAuthenticationCanceledException();
+}
+
+@Singleton(as: GoogleAuthenticationService)
+class GoogleSignInAuthenticationService implements GoogleAuthenticationService {
+  GoogleSignInAuthenticationService({@ignoreParam GoogleSignIn? googleSignIn})
+    : _googleSignIn = googleSignIn ?? GoogleSignIn.instance;
+
+  static const _googleIosClientId =
+      '456571312261-r35ah9qi0qaq7al007e2db0e0jmjcmb4.apps.googleusercontent.com';
+  static const _googleServerClientId =
+      '456571312261-5kuf2r6i5i7lqjr7qealv06sdgkn3hcp.apps.googleusercontent.com';
+  static const _googleScopes = ['email', 'profile'];
+
+  final GoogleSignIn _googleSignIn;
+  Future<void>? _initialization;
+
+  @override
+  Stream<GoogleAuthCredential> get authenticationCredentials => _googleSignIn
+      .authenticationEvents
+      .where((event) => event is GoogleSignInAuthenticationEventSignIn)
+      .cast<GoogleSignInAuthenticationEventSignIn>()
+      .map((event) => _credentialFromAccount(event.user));
+
+  @override
+  bool get supportsAuthenticate => _googleSignIn.supportsAuthenticate();
+
+  @override
+  Future<void> initialize() {
+    return _initialization ??= _initialize();
+  }
+
+  Future<void> _initialize() async {
+    await _googleSignIn.initialize(
+      clientId: _googleClientId,
+      serverClientId: _googleServerClientId,
+    );
+  }
+
+  @override
+  Future<GoogleAuthCredential> authenticate() async {
+    try {
+      await initialize();
+      final account = await _googleSignIn.authenticate(
+        scopeHint: _googleScopes,
+      );
+      return _credentialFromAccount(account);
+    } on GoogleSignInException catch (error) {
+      if (error.code == GoogleSignInExceptionCode.canceled) {
+        throw const GoogleAuthenticationCanceledException();
+      }
+      rethrow;
+    }
+  }
+
+  @override
+  Future<void> disconnect() async {
+    try {
+      await _googleSignIn.disconnect();
+      AppLogger.debug('Google Sign-In disconnected');
+    } catch (error) {
+      AppLogger.debug(
+        'Google Sign-In disconnect failed errorType=${error.runtimeType}',
+      );
+    }
+  }
+
+  GoogleAuthCredential _credentialFromAccount(GoogleSignInAccount account) {
+    final idToken = account.authentication.idToken;
+    if (idToken == null) {
+      throw Exception('Google ID Token is null');
+    }
+    return GoogleAuthCredential(idToken: idToken);
+  }
+
+  String? get _googleClientId {
+    if (kIsWeb) return null;
+    return defaultTargetPlatform == TargetPlatform.iOS
+        ? _googleIosClientId
+        : null;
+  }
+}

lib/data/repositories/user_repository_impl.dart

@@ -1,65 +1,34 @@
 import 'dart:async';
 
 import 'package:dio/dio.dart';
-import 'package:flutter/foundation.dart';
-import 'package:google_sign_in/google_sign_in.dart';
 import 'package:injectable/injectable.dart';
 import 'package:on_time_front/core/logging/app_logger.dart';
+import 'package:on_time_front/core/services/google_authentication_service.dart';
 import 'package:on_time_front/core/validation/backend_constraints.dart';
 import 'package:on_time_front/data/data_sources/authentication_remote_data_source.dart';
 import 'package:on_time_front/data/data_sources/token_local_data_source.dart';
 import 'package:on_time_front/data/models/sign_in_with_google_request_model.dart';
 import 'package:on_time_front/data/models/sign_in_with_apple_request_model.dart';
+import 'package:on_time_front/domain/entities/google_auth_credential.dart';
 import 'package:on_time_front/domain/entities/user_entity.dart';
 import 'package:on_time_front/domain/repositories/user_repository.dart';
 import 'package:rxdart/subjects.dart';
 
 @Singleton(as: UserRepository)
 class UserRepositoryImpl implements UserRepository {
-  static const _googleIosClientId =
-      '456571312261-r35ah9qi0qaq7al007e2db0e0jmjcmb4.apps.googleusercontent.com';
-  static const _googleServerClientId =
-      '456571312261-5kuf2r6i5i7lqjr7qealv06sdgkn3hcp.apps.googleusercontent.com';
-  static const _googleScopes = ['email', 'profile'];
-
   final AuthenticationRemoteDataSource _authenticationRemoteDataSource;
   final TokenLocalDataSource _tokenLocalDataSource;
-  final GoogleSignIn _googleSignIn = GoogleSignIn.instance;
-  Future<void>? _googleSignInInitialization;
+  final GoogleAuthenticationService _googleAuthenticationService;
   late final _userStreamController = BehaviorSubject<UserEntity>.seeded(
     const UserEntity.empty(),
   );
 
-  @override
-  Stream<GoogleSignInAuthenticationEvent> get googleAuthenticationEvents =>
-      _googleSignIn.authenticationEvents;
-
-  @override
-  bool get supportsGoogleAuthenticate => _googleSignIn.supportsAuthenticate();
-
   UserRepositoryImpl(
     this._authenticationRemoteDataSource,
     this._tokenLocalDataSource,
+    this._googleAuthenticationService,
   );
 
-  @override
-  Future<void> initializeGoogleSignIn() {
-    return _googleSignInInitialization ??= _initializeGoogleSignIn();
-  }
-
-  Future<void> _initializeGoogleSignIn() async {
-    await _googleSignIn.initialize(
-      clientId: _googleClientId,
-      serverClientId: _googleServerClientId,
-    );
-  }
-
-  @override
-  Future<GoogleSignInAccount> authenticateWithGoogle() async {
-    await initializeGoogleSignIn();
-    return _googleSignIn.authenticate(scopeHint: _googleScopes);
-  }
-
   @override
   Future<UserEntity> getUser() async {
     try {
@@ -122,16 +91,14 @@ class UserRepositoryImpl implements UserRepository {
   }
 
   @override
-  Future<void> signInWithGoogle(GoogleSignInAccount googleUser) async {
+  Future<void> signInWithGoogle(GoogleAuthCredential credential) async {
     try {
-      final GoogleSignInAuthentication googleAuth = googleUser.authentication;
-      final String? idToken = googleAuth.idToken;
-      if (idToken == null) {
+      if (credential.idToken.isEmpty) {
         throw Exception('Google ID Token is null');
       }
       final signInWithGoogleRequestModel = SignInWithGoogleRequestModel(
-        idToken: idToken,
-        refreshToken: '',
+        idToken: credential.idToken,
+        refreshToken: credential.refreshToken,
       );
       await _tokenLocalDataSource.deleteToken();
       final result = await _authenticationRemoteDataSource.signInWithGoogle(
@@ -225,8 +192,7 @@ class UserRepositoryImpl implements UserRepository {
   @override
   Future<void> disconnectGoogleSignIn() async {
     try {
-      await _googleSignIn.disconnect();
-      AppLogger.debug('Google Sign-In disconnected');
+      await _googleAuthenticationService.disconnect();
     } catch (error) {
       AppLogger.debug(
         'Google Sign-In disconnect failed errorType=${error.runtimeType}',
@@ -237,11 +203,4 @@ class UserRepositoryImpl implements UserRepository {
   @override
   Stream<UserEntity> get userStream =>
       _userStreamController.asBroadcastStream();
-
-  String? get _googleClientId {
-    if (kIsWeb) return null;
-    return defaultTargetPlatform == TargetPlatform.iOS
-        ? _googleIosClientId
-        : null;
-  }
 }

lib/domain/entities/google_auth_credential.dart

@@ -0,0 +1,6 @@
+class GoogleAuthCredential {
+  const GoogleAuthCredential({required this.idToken, this.refreshToken = ''});
+
+  final String idToken;
+  final String refreshToken;
+}

lib/domain/repositories/user_repository.dart

@@ -1,17 +1,9 @@
-import 'package:google_sign_in/google_sign_in.dart';
+import 'package:on_time_front/domain/entities/google_auth_credential.dart';
 import 'package:on_time_front/domain/entities/user_entity.dart';
 
 abstract interface class UserRepository {
   Stream<UserEntity> get userStream;
 
-  Stream<GoogleSignInAuthenticationEvent> get googleAuthenticationEvents;
-
-  Future<void> initializeGoogleSignIn();
-
-  bool get supportsGoogleAuthenticate;
-
-  Future<GoogleSignInAccount> authenticateWithGoogle();
-
   Future<void> signUp({
     required String email,
     required String password,
@@ -22,7 +14,7 @@ abstract interface class UserRepository {
 
   Future<void> signOut();
 
-  Future<void> signInWithGoogle(GoogleSignInAccount account);
+  Future<void> signInWithGoogle(GoogleAuthCredential credential);
 
   Future<void> signInWithApple({
     required String idToken,

lib/presentation/login/components/google_sign_in_button/google_sign_in_button_web.dart

@@ -1,9 +1,10 @@
 import 'dart:async';
 
 import 'package:flutter/widgets.dart';
-import 'package:google_sign_in/google_sign_in.dart';
 import 'package:google_sign_in_web/web_only.dart';
 import 'package:on_time_front/core/di/di_setup.dart';
+import 'package:on_time_front/core/services/google_authentication_service.dart';
+import 'package:on_time_front/domain/entities/google_auth_credential.dart';
 import 'package:on_time_front/domain/repositories/user_repository.dart';
 
 class GoogleSignInButton extends StatefulWidget {
@@ -16,26 +17,27 @@ class GoogleSignInButton extends StatefulWidget {
 }
 
 class _GoogleSignInButtonState extends State<GoogleSignInButton> {
-  final authenticationRepository = getIt.get<UserRepository>();
-  late final Stream<GoogleSignInAuthenticationEvent> _authenticationEvents;
-  StreamSubscription<GoogleSignInAuthenticationEvent>?
-  _authenticationEventsSubscription;
+  final googleAuthenticationService = getIt.get<GoogleAuthenticationService>();
+  late final Stream<GoogleAuthCredential> _authenticationCredentials;
+  StreamSubscription<GoogleAuthCredential>?
+  _authenticationCredentialsSubscription;
 
   @override
   void initState() {
-    _authenticationEvents = authenticationRepository.googleAuthenticationEvents;
-    unawaited(authenticationRepository.initializeGoogleSignIn());
-    _authenticationEventsSubscription = _authenticationEvents.listen((event) {
-      if (event is GoogleSignInAuthenticationEventSignIn) {
-        unawaited(getIt.get<UserRepository>().signInWithGoogle(event.user));
-      }
+    _authenticationCredentials =
+        googleAuthenticationService.authenticationCredentials;
+    unawaited(googleAuthenticationService.initialize());
+    _authenticationCredentialsSubscription = _authenticationCredentials.listen((
+      credential,
+    ) {
+      unawaited(getIt.get<UserRepository>().signInWithGoogle(credential));
     });
     super.initState();
   }
 
   @override
   void dispose() {
-    unawaited(_authenticationEventsSubscription?.cancel());
+    unawaited(_authenticationCredentialsSubscription?.cancel());
     super.dispose();
   }
 

lib/presentation/login/screens/sign_in_main_screen.dart

@@ -2,9 +2,9 @@ import 'package:flutter/material.dart';
 import 'package:flutter_svg/flutter_svg.dart';
 import 'package:flutter/foundation.dart';
 import 'dart:io' show Platform;
-import 'package:google_sign_in/google_sign_in.dart';
 import 'package:on_time_front/core/di/di_setup.dart';
 import 'package:on_time_front/core/logging/app_logger.dart';
+import 'package:on_time_front/core/services/google_authentication_service.dart';
 import 'package:on_time_front/domain/repositories/user_repository.dart';
 import 'package:on_time_front/l10n/app_localizations.dart';
 import 'package:on_time_front/presentation/shared/components/modal_wide_button.dart';
@@ -105,8 +105,10 @@ class _SignInMainScreenState extends State<SignInMainScreen> {
 
   Future<void> _defaultGoogleSignIn() async {
     final userRepository = getIt.get<UserRepository>();
-    final googleAccount = await userRepository.authenticateWithGoogle();
-    await userRepository.signInWithGoogle(googleAccount);
+    final credential = await getIt
+        .get<GoogleAuthenticationService>()
+        .authenticate();
+    await userRepository.signInWithGoogle(credential);
   }
 
   Future<void> _defaultAppleSignIn() async {
@@ -137,8 +139,7 @@ class _SignInMainScreenState extends State<SignInMainScreen> {
   }
 
   bool _isUserCancellation(Object error) {
-    return error is GoogleSignInException &&
-            error.code == GoogleSignInExceptionCode.canceled ||
+    return error is GoogleAuthenticationCanceledException ||
         error is SignInWithAppleAuthorizationException &&
             error.code == AuthorizationErrorCode.canceled;
   }