// AuthBloc 单元测试
//
// 覆盖：App启动恢复、登录/注册、角色选择、班级码加入、登出、认证过期
// 使用 mocktail 手动 mock AuthRepository 和 ClassRepository

import 'package:dio/dio.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:mocktail/mocktail.dart';
import 'package:nuanji_app/data/models/auth_token.dart';
import 'package:nuanji_app/data/models/school_class.dart';
import 'package:nuanji_app/data/models/user.dart';
import 'package:nuanji_app/data/remote/api_client.dart';
import 'package:nuanji_app/data/repositories/auth_repository.dart';
import 'package:nuanji_app/data/repositories/class_repository.dart';
import 'package:nuanji_app/features/auth/bloc/auth_bloc.dart';

// ===== Mock 类 =====

class MockAuthRepository extends Mock implements AuthRepository {}

class MockClassRepository extends Mock implements ClassRepository {}

// ===== 测试数据 =====

const _testUser = User(
  id: 'u-001',
  username: 'testuser',
  displayName: '测试用户',
);

const _testUserWithRole = User(
  id: 'u-002',
  username: 'roleduser',
  displayName: '有角色用户',
  roles: [
    UserRole(
      id: 'r-001',
      name: '学生',
      code: 'student',
    ),
  ],
);

final _testSchoolClass = SchoolClass(
  id: 'c-001',
  name: '三年级一班',
  schoolName: '阳光小学',
  teacherId: 't-001',
  classCode: 'ABC123',
  createdAt: DateTime(2026, 1, 1),
  updatedAt: DateTime(2026, 1, 1),
);

// TokenRefreshed 测试用 — DateTime 不是编译期常量，因此用 final
final _testToken = AuthToken(
  accessToken: 'access-token',
  refreshToken: 'refresh-token',
  expiresIn: 3600,
  expiresAt: DateTime.parse('2099-12-31T23:59:59Z'),
);

void main() {
  late MockAuthRepository mockAuthRepo;
  late MockClassRepository mockClassRepo;
  late AuthBloc bloc;

  setUpAll(() {
    // 为 mocktail 的 any() 匹配器注册 String fallback 值
    registerFallbackValue('');
  });

  setUp(() {
    mockAuthRepo = MockAuthRepository();
    mockClassRepo = MockClassRepository();
    bloc = AuthBloc(
      authRepository: mockAuthRepo,
      classRepository: mockClassRepo,
    );
  });

  tearDown(() {
    bloc.close();
  });

  // ===== 辅助 =====

  /// 派发事件并等待 BLoC 处理完毕，返回最终状态
  Future<AuthState> dispatch(AuthEvent event) async {
    bloc.add(event);
    await Future<void>.delayed(const Duration(milliseconds: 50));
    return bloc.state;
  }

  /// 先将 BLoC 推入 Authenticated 状态，方便测试角色/班级码等后续流程
  Future<void> seedAuthenticated({
    User user = _testUser,
    bool needsRoleSelection = false,
    bool needsClassCode = false,
  }) async {
    bloc.emit(Authenticated(
      user: user,
      needsRoleSelection: needsRoleSelection,
      needsClassCode: needsClassCode,
    ));
    await Future<void>.delayed(const Duration(milliseconds: 10));
  }

  // ===== AppStarted =====

  group('AppStarted', () {
    test('有本地用户 → Authenticated', () async {
      // arrange
      when(() => mockAuthRepo.restoreAuth()).thenAnswer((_) async => _testUser);

      // act
      final state = await dispatch(const AppStarted());

      // assert
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.user.id, equals('u-001'));
      expect(authenticated.needsRoleSelection, isTrue); // _testUser 没有 roles
      verify(() => mockAuthRepo.restoreAuth()).called(1);
    });

    test('无本地用户 → Unauthenticated', () async {
      // arrange
      when(() => mockAuthRepo.restoreAuth()).thenAnswer((_) async => null);

      // act
      final state = await dispatch(const AppStarted());

      // assert
      expect(state, isA<Unauthenticated>());
      verify(() => mockAuthRepo.restoreAuth()).called(1);
    });

    test('restoreAuth 异常 → Unauthenticated', () async {
      // arrange
      when(() => mockAuthRepo.restoreAuth()).thenThrow(Exception('存储损坏'));

      // act
      final state = await dispatch(const AppStarted());

      // assert — 异常不冒泡，而是降级为未认证
      expect(state, isA<Unauthenticated>());
      verify(() => mockAuthRepo.restoreAuth()).called(1);
    });
  });

  // ===== LoginRequested =====

  group('LoginRequested', () {
    test('成功 → Authenticating → Authenticated', () async {
      // arrange
      when(() => mockAuthRepo.login(
            username: any(named: 'username'),
            password: any(named: 'password'),
          )).thenAnswer((_) async => _testUserWithRole);

      // act
      final state = await dispatch(
        const LoginRequested(username: 'testuser', password: 'pass123'),
      );

      // assert — 有角色的用户，needsRoleSelection 为 false
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.user.id, equals('u-002'));
      expect(authenticated.needsRoleSelection, isFalse);
      verify(() => mockAuthRepo.login(
            username: 'testuser',
            password: 'pass123',
          )).called(1);
    });

    test('AuthException → AuthError', () async {
      // arrange
      when(() => mockAuthRepo.login(
            username: any(named: 'username'),
            password: any(named: 'password'),
          )).thenThrow(const AuthException('用户名或密码错误'));

      // act
      final state = await dispatch(
        const LoginRequested(username: 'bad', password: 'wrong'),
      );

      // assert
      expect(state, isA<AuthError>());
      final error = state as AuthError;
      expect(error.message, equals('用户名或密码错误'));
      expect(error.retryable, isTrue); // 默认可重试
    });

    test('OfflineException → AuthError(retryable: true)', () async {
      // arrange
      when(() => mockAuthRepo.login(
            username: any(named: 'username'),
            password: any(named: 'password'),
          )).thenThrow(const OfflineException());

      // act
      final state = await dispatch(
        const LoginRequested(username: 'user', password: 'pass'),
      );

      // assert
      expect(state, isA<AuthError>());
      final error = state as AuthError;
      expect(error.message, contains('网络'));
      expect(error.retryable, isTrue);
    });
  });

  // ===== RegisterRequested =====

  group('RegisterRequested', () {
    test('成功 → Authenticating(isRegister:true) → Authenticated(needsRoleSelection:true)', () async {
      // arrange
      when(() => mockAuthRepo.register(
            username: any(named: 'username'),
            password: any(named: 'password'),
            displayName: any(named: 'displayName'),
          )).thenAnswer((_) async => _testUser);

      // act
      final state = await dispatch(
        const RegisterRequested(
          username: 'newuser',
          password: 'pass123',
          displayName: '小明',
        ),
      );

      // assert — 注册后必须选角色
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.needsRoleSelection, isTrue);
      verify(() => mockAuthRepo.register(
            username: 'newuser',
            password: 'pass123',
            displayName: '小明',
          )).called(1);
    });
  });

  // ===== RoleSelected =====

  group('RoleSelected', () {
    test('选择 student → needsClassCode:true', () async {
      // arrange — 从 Authenticated 状态开始
      await seedAuthenticated();

      // act
      final state = await dispatch(const RoleSelected(UserRoleType.student));

      // assert
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.needsRoleSelection, isFalse);
      expect(authenticated.needsClassCode, isTrue);
    });

    test('选择 teacher → needsClassCode:false', () async {
      // arrange
      await seedAuthenticated();

      // act
      final state = await dispatch(const RoleSelected(UserRoleType.teacher));

      // assert
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.needsRoleSelection, isFalse);
      expect(authenticated.needsClassCode, isFalse);
    });

    test('当前非 Authenticated → 状态不变', () async {
      // arrange — bloc 初始状态为 AuthInitial
      expect(bloc.state, isA<AuthInitial>());

      // act
      final state = await dispatch(const RoleSelected(UserRoleType.student));

      // assert — 状态未改变
      expect(state, isA<AuthInitial>());
    });
  });

  // ===== ClassCodeSubmitted =====

  group('ClassCodeSubmitted', () {
    test('成功 → needsClassCode:false', () async {
      // arrange
      await seedAuthenticated(needsClassCode: true);
      when(() => mockClassRepo.joinClass(any(), nickname: any(named: 'nickname')))
          .thenAnswer((_) async => _testSchoolClass);

      // act
      final state = await dispatch(const ClassCodeSubmitted('ABC123'));

      // assert
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.needsClassCode, isFalse);
      expect(authenticated.isLoading, isFalse);
      expect(authenticated.classCodeError, isNull);
      verify(() => mockClassRepo.joinClass('ABC123', nickname: '测试用户')).called(1);
    });

    test('429 → classCodeError 包含 "30分钟"', () async {
      // arrange
      await seedAuthenticated(needsClassCode: true);

      // 构造 429 DioException
      final dioError = DioException(
        requestOptions: RequestOptions(path: '/diary/classes/join'),
        response: Response(
          requestOptions: RequestOptions(path: '/diary/classes/join'),
          statusCode: 429,
        ),
      );
      when(() => mockClassRepo.joinClass(any(), nickname: any(named: 'nickname')))
          .thenThrow(dioError);

      // act
      final state = await dispatch(const ClassCodeSubmitted('BADCODE'));

      // assert
      expect(state, isA<Authenticated>());
      final authenticated = state as Authenticated;
      expect(authenticated.isLoading, isFalse);
      expect(authenticated.classCodeError, contains('30 分钟'));
      expect(authenticated.needsClassCode, isTrue); // 仍然需要班级码
    });
  });

  // ===== LogoutRequested =====

  group('LogoutRequested', () {
    test('登出 → Unauthenticated', () async {
      // arrange
      await seedAuthenticated();
      when(() => mockAuthRepo.logout()).thenAnswer((_) async {});

      // act
      final state = await dispatch(const LogoutRequested());

      // assert
      expect(state, isA<Unauthenticated>());
      verify(() => mockAuthRepo.logout()).called(1);
    });

    test('logout 抛异常 → 仍为 Unauthenticated（错误忽略）', () async {
      // arrange
      await seedAuthenticated();
      when(() => mockAuthRepo.logout()).thenThrow(Exception('网络错误'));

      // act
      final state = await dispatch(const LogoutRequested());

      // assert — 即使 logout 失败，状态也变为 Unauthenticated
      expect(state, isA<Unauthenticated>());
    });
  });

  // ===== AuthExpired =====

  group('AuthExpired', () {
    test('认证过期 → Unauthenticated', () async {
      // arrange — 从已认证状态开始
      await seedAuthenticated();

      // act
      final state = await dispatch(const AuthExpired());

      // assert
      expect(state, isA<Unauthenticated>());
    });
  });

  // ===== TokenRefreshed =====

  group('TokenRefreshed', () {
    test('令牌刷新 → 状态不变', () async {
      // arrange — 从已认证状态开始
      await seedAuthenticated();
      final stateBefore = bloc.state;

      // act
      final state = await dispatch(TokenRefreshed(_testToken));

      // assert — 状态不变
      expect(state, equals(stateBefore));
    });
  });
}