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lib/shared/services/google_auth_service.dart

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+import 'dart:async';
+import 'package:google_sign_in/google_sign_in.dart';
+
+class GoogleAuthService {
+  final GoogleSignIn _googleSignIn;
+
+  GoogleAuthService() : _googleSignIn = GoogleSignIn(scopes: ['email']);
+
+  GoogleSignInAccount? get currentUser => _googleSignIn.currentUser;
+
+  Stream<GoogleSignInAccount?> get onCurrentUserChanged =>
+      _googleSignIn.onCurrentUserChanged;
+
+  Future<void> signIn() async {
+    await _googleSignIn.signIn();
+  }
+
+  Future<void> signOut() async {
+    await _googleSignIn.signOut();
+  }
+}