import 'package:equatable/equatable.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:focusflow_shared/focusflow_shared.dart';

import '../../../../core/network/api_client.dart';
import '../../../../core/network/interceptors/auth_interceptor.dart';
import '../../../../main.dart';

// ── Events ─────────────────────────────────────────────────────────

sealed class AuthEvent extends Equatable {
  const AuthEvent();
  @override
  List<Object?> get props => [];
}

class AuthLoginRequested extends AuthEvent {
  final String email;
  final String password;
  const AuthLoginRequested({required this.email, required this.password});
  @override
  List<Object?> get props => [email, password];
}

class AuthSignupRequested extends AuthEvent {
  final String displayName;
  final String email;
  final String password;
  const AuthSignupRequested({
    required this.displayName,
    required this.email,
    required this.password,
  });
  @override
  List<Object?> get props => [displayName, email, password];
}

class AuthLogoutRequested extends AuthEvent {
  const AuthLogoutRequested();
}

class AuthCheckRequested extends AuthEvent {}

// ── States ─────────────────────────────────────────────────────────

sealed class AuthState extends Equatable {
  const AuthState();
  @override
  List<Object?> get props => [];
}

class AuthInitial extends AuthState {}

class AuthLoading extends AuthState {}

class AuthAuthenticated extends AuthState {
  final User user;
  const AuthAuthenticated(this.user);
  @override
  List<Object?> get props => [user];
}

class AuthUnauthenticated extends AuthState {}

class AuthError extends AuthState {
  final String message;
  const AuthError(this.message);
  @override
  List<Object?> get props => [message];
}

// ── BLoC ───────────────────────────────────────────────────────────

class AuthBloc extends Bloc<AuthEvent, AuthState> {
  final ApiClient _api = getIt<ApiClient>();

  AuthBloc() : super(AuthInitial()) {
    on<AuthCheckRequested>(_onCheck);
    on<AuthLoginRequested>(_onLogin);
    on<AuthSignupRequested>(_onSignup);
    on<AuthLogoutRequested>(_onLogout);
  }

  Future<void> _onCheck(AuthCheckRequested event, Emitter<AuthState> emit) async {
    final hasToken = await AuthInterceptor.hasToken();
    if (hasToken) {
      // In a production app we would validate the token and fetch the user profile.
      // For now we emit a placeholder user.
      emit(AuthAuthenticated(
        User(
          id: 'local',
          email: '',
          displayName: 'Friend',
          createdAt: DateTime.now(),
        ),
      ));
    } else {
      emit(AuthUnauthenticated());
    }
  }

  Future<void> _onLogin(AuthLoginRequested event, Emitter<AuthState> emit) async {
    emit(AuthLoading());
    try {
      final response = await _api.login(event.email, event.password);
      if (response.status == 'success' && response.data != null) {
        final data = response.data!;
        await AuthInterceptor.saveTokens(
          accessToken: data['accessToken'] as String,
          refreshToken: data['refreshToken'] as String,
        );
        final user = User.fromJson(data['user'] as Map<String, dynamic>);
        emit(AuthAuthenticated(user));
      } else {
        emit(AuthError(response.error?.message ?? 'Login failed'));
      }
    } catch (e) {
      emit(AuthError('Something went wrong. Please try again.'));
    }
  }

  Future<void> _onSignup(AuthSignupRequested event, Emitter<AuthState> emit) async {
    emit(AuthLoading());
    try {
      final response = await _api.register(event.displayName, event.email, event.password);
      if (response.status == 'success' && response.data != null) {
        final data = response.data!;
        await AuthInterceptor.saveTokens(
          accessToken: data['accessToken'] as String,
          refreshToken: data['refreshToken'] as String,
        );
        final user = User.fromJson(data['user'] as Map<String, dynamic>);
        emit(AuthAuthenticated(user));
      } else {
        emit(AuthError(response.error?.message ?? 'Sign up failed'));
      }
    } catch (e) {
      emit(AuthError('Something went wrong. Please try again.'));
    }
  }

  Future<void> _onLogout(AuthLogoutRequested event, Emitter<AuthState> emit) async {
    try {
      await _api.logout();
    } catch (_) {
      // Best-effort server logout — clear local tokens regardless.
    }
    await AuthInterceptor.clearTokens();
    emit(AuthUnauthenticated());
  }
}