Flutter 딥링킹 완벽 가이드 5편: 실전 통합 구현

// main.dart
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  
  // 1. 필수 서비스 초기화
  await AppInitializer.initialize();
  
  runApp(
    ProviderScope(
      child: MyApp(),
    ),
  );
}

// services/app_initializer.dart
class AppInitializer {
  static Future<void> initialize() async {
    try {
      // 1단계: 로컬 저장소
      await _initializeStorage();
      
      // 2단계: 인증 서비스
      await _initializeAuth();
      
      // 3단계: 원격 설정
      await _initializeRemoteConfig();
      
      // 4단계: 분석 서비스
      await _initializeAnalytics();
      
      print('앱 초기화 완료');
    } catch (e) {
      print('초기화 실패: $e');
      // 크리티컬 에러 처리
    }
  }
  
  static Future<void> _initializeStorage() async {
    // SharedPreferences, Hive 등 초기화
  }
  
  static Future<void> _initializeAuth() async {
    // Firebase Auth, 토큰 검증 등
  }
  
  static Future<void> _initializeRemoteConfig() async {
    // Firebase Remote Config 등
  }
  
  static Future<void> _initializeAnalytics() async {
    // Firebase Analytics, Amplitude 등
  }
}

// app.dart
class MyApp extends ConsumerStatefulWidget {
  @override
  ConsumerState<MyApp> createState() => _MyAppState();
}

class _MyAppState extends ConsumerState<MyApp> {
  late final GoRouter _router;
  late final DeepLinkService _deepLinkService;

  @override
  void initState() {
    super.initState();
    _initializeRouter();
    _initializeDeepLinks();
  }

  void _initializeRouter() {
    _router = GoRouter(
      initialLocation: '/splash',
      redirect: (context, state) => _handleRedirect(state),
      routes: [
        GoRoute(
          path: '/splash',
          builder: (context, state) => const SplashScreen(),
        ),
        GoRoute(
          path: '/',
          builder: (context, state) => const HomeScreen(),
        ),
        GoRoute(
          path: '/login',
          builder: (context, state) => const LoginScreen(),
        ),
        GoRoute(
          path: '/product/:id',
          builder: (context, state) {
            final id = state.pathParameters['id']!;
            return ProductScreen(productId: id);
          },
        ),
      ],
    );
    
    // Riverpod에 라우터 연결
    ref.read(routerProvider.notifier).setRouter(_router);
  }

  void _initializeDeepLinks() {
    _deepLinkService = DeepLinkService();
    
    // 딥링크 스트림 구독
    _deepLinkService.linkStream.listen((link) {
      _handleDeepLink(link);
    });
    
    // 초기 딥링크 처리
    _deepLinkService.initialize();
  }

  void _handleDeepLink(String link) {
    // 1. 검증
    if (!DeepLinkValidator.isValid(link)) {
      _showError('잘못된 링크입니다');
      return;
    }
    
    // 2. 파싱
    final data = DeepLinkData.fromUrl(link);
    
    // 3. 라우팅
    _router.go(data.path);
  }

  String? _handleRedirect(GoRouterState state) {
    final isLoggedIn = ref.read(authProvider);
    final isOnboardingComplete = ref.read(onboardingProvider);
    
    // 온보딩 체크
    if (!isOnboardingComplete && state.location != '/onboarding') {
      return '/onboarding';
    }
    
    // 인증 체크
    if (!isLoggedIn && _requiresAuth(state.location)) {
      return '/login?redirect=${Uri.encodeComponent(state.location)}';
    }
    
    // 스플래시에서 자동 이동
    if (state.location == '/splash') {
      return isLoggedIn ? '/' : '/login';
    }
    
    return null;
  }

  bool _requiresAuth(String location) {
    final publicRoutes = ['/', '/login', '/register', '/splash'];
    return !publicRoutes.any((route) => location.startsWith(route));
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp.router(
      title: 'My App',
      routerConfig: _router,
      theme: ThemeData(primarySwatch: Colors.blue),
    );
  }

  void _showError(String message) {
    // 에러 표시 로직
  }
}

// examples/push_notification_handler.dart
class PushNotificationHandler {
  final GoRouter router;
  
  PushNotificationHandler(this.router);
  
  void handleNotification(RemoteMessage message) {
    // 딥링크 추출
    final deepLink = message.data['deep_link'];
    if (deepLink == null) return;
    
    // 앱 상태에 따른 처리
    if (message.notification != null) {
      // 포그라운드: 다이얼로그 표시
      _showNotificationDialog(
        title: message.notification!.title,
        body: message.notification!.body,
        onTap: () => router.go(deepLink),
      );
    } else {
      // 백그라운드/종료: 바로 이동
      router.go(deepLink);
    }
  }
  
  void _showNotificationDialog({
    String? title,
    String? body,
    VoidCallback? onTap,
  }) {
    // 알림 다이얼로그 표시
  }
}

// examples/share_handler.dart
class ShareHandler {
  static String generateShareLink({
    required String contentType,
    required String contentId,
    String? sharedBy,
  }) {
    final params = {
      'type': contentType,
      'id': contentId,
      if (sharedBy != null) 'ref': sharedBy,
      'utm_source': 'share',
      'utm_medium': 'social',
    };
    
    return Uri.https(
      'myapp.com',
      '/share',
      params,
    ).toString();
  }
  
  static void handleShareLink(String link) {
    final uri = Uri.parse(link);
    final contentType = uri.queryParameters['type'];
    final contentId = uri.queryParameters['id'];
    final referrer = uri.queryParameters['ref'];
    
    // 분석 이벤트
    Analytics.track('share_opened', {
      'content_type': contentType,
      'content_id': contentId,
      'referrer': referrer,
    });
    
    // 콘텐츠로 이동
    switch (contentType) {
      case 'product':
        router.go('/product/$contentId');
        break;
      case 'post':
        router.go('/post/$contentId');
        break;
      default:
        router.go('/');
    }
  }
}

// test/deeplink_test.dart
import 'package:flutter_test/flutter_test.dart';

void main() {
  group('DeepLink Validation', () {
    test('유효한 URL을 허용해야 함', () {
      expect(
        DeepLinkValidator.isValid('myapp://product/123'),
        isTrue,
      );
      expect(
        DeepLinkValidator.isValid('https://myapp.com/user/john'),
        isTrue,
      );
    });
    
    test('잘못된 URL을 거부해야 함', () {
      expect(
        DeepLinkValidator.isValid('badscheme://product/123'),
        isFalse,
      );
      expect(
        DeepLinkValidator.isValid('myapp://../../etc/passwd'),
        isFalse,
      );
    });
  });
  
  group('Router State', () {
    late ProviderContainer container;
    
    setUp(() {
      container = ProviderContainer();
    });
    
    test('네비게이션 히스토리를 추적해야 함', () {
      final notifier = container.read(routerProvider.notifier);
      
      notifier.updateLocation('/');
      notifier.updateLocation('/product/123');
      notifier.updateLocation('/cart');
      
      final state = container.read(routerProvider);
      expect(state.history, contains('/product/123'));
      expect(state.canGoBack, isTrue);
    });
  });
}

// test/integration/deeplink_flow_test.dart
testWidgets('딥링크 전체 플로우', (tester) async {
  await tester.pumpWidget(MyApp());
  
  // 앱 초기화 대기
  await tester.pumpAndSettle();
  
  // 딥링크 시뮬레이션
  final deepLink = 'myapp://product/test-product';
  DeepLinkService().handleLink(deepLink);
  
  // 화면 전환 대기
  await tester.pumpAndSettle();
  
  // 제품 화면이 표시되는지 확인
  expect(find.text('test-product'), findsOneWidget);
});