import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../network/api_client.dart';
import '../storage/token_storage.dart';

class AuthState {
  final bool authenticated;
  final int? userId;
  final String? name;

  const AuthState({
    this.authenticated = false,
    this.userId,
    this.name,
  });
}

final tokenStorageProvider = Provider<TokenStorage>((ref) => TokenStorage());

final apiClientProvider = Provider<ApiClient>((ref) {
  final client = ApiClient(tokenStorage: ref.watch(tokenStorageProvider));
  client.onUnauthorized = () {
    ref.read(authProvider.notifier).logout();
  };
  return client;
});

class AuthNotifier extends AsyncNotifier<AuthState> {
  @override
  Future<AuthState> build() async {
    final storage = ref.watch(tokenStorageProvider);
    await storage.load();
    return AuthState(authenticated: storage.hasToken);
  }

  Future<void> login(String account, String password) async {
    state = const AsyncLoading();
    try {
      final client = ref.read(apiClientProvider);
      final data = await client.post<Map<String, dynamic>>('/user/login', {
        'account': account,
        'password': password,
      });
      final token = data['token'] as String? ?? '';
      final user = data['user'] as Map<String, dynamic>? ?? {};
      await ref.read(tokenStorageProvider).save(token);
      state = AsyncData(AuthState(
        authenticated: true,
        userId: (user['id'] as num?)?.toInt(),
        name: user['name'] as String?,
      ));
    } catch (e) {
      state = AsyncError(e, StackTrace.current);
    }
  }

  Future<void> logout() async {
    await ref.read(tokenStorageProvider).clear();
    state = const AsyncData(AuthState());
  }
}

final authProvider =
    AsyncNotifierProvider<AuthNotifier, AuthState>(AuthNotifier.new);