import 'package:dio/dio.dart';
import 'package:riverpod_annotation/riverpod_annotation.dart';

import '../api/api_client.dart';
import 'permissions.dart';
import 'user_preferences.dart';

part 'auth_datasource.g.dart';

/// Response from POST /auth/sync endpoint.
class AuthSyncResponse {
  const AuthSyncResponse({
    required this.userId,
    required this.authentikId,
    required this.email,
    required this.name,
    this.avatarUrl,
    required this.roles,
    required this.preferences,
    required this.isNewUser,
  });

  final String userId;
  final String authentikId;
  final String email;
  final String name;
  final String? avatarUrl;
  final List<Role> roles;
  final UserPreferences preferences;
  final bool isNewUser;

  factory AuthSyncResponse.fromJson(Map<String, dynamic> json) {
    final user = json['user'] as Map<String, dynamic>;
    final rolesJson = json['roles'] as List<dynamic>;
    final prefsJson = json['preferences'] as Map<String, dynamic>;

    return AuthSyncResponse(
      userId: user['id'] as String,
      authentikId: user['authentik_id'] as String,
      email: user['email'] as String,
      name: user['name'] as String,
      avatarUrl: user['avatar_url'] as String?,
      roles: rolesJson.map((r) => _parseRole(r as Map<String, dynamic>)).toList(),
      preferences: UserPreferences.fromJson(prefsJson),
      isNewUser: json['is_new_user'] as bool,
    );
  }
}

/// Parse a role from API JSON.
Role _parseRole(Map<String, dynamic> json) {
  final name = json['name'] as String;
  final domainStr = json['domain'] as String;
  final category = json['category'] as String? ?? 'general';
  final actionStr = json['action'] as String;

  final domain = Domain.fromString(domainStr);
  final action = Action.fromString(actionStr);

  if (domain == null || action == null) {
    // Return a placeholder role for unknown domains/actions
    return Role(
      id: json['id'] as String,
      name: name,
      domain: Domain.admin, // Fallback
      category: category,
      action: Action.viewer, // Fallback - least privilege
    );
  }

  return Role(
    id: json['id'] as String,
    name: name,
    domain: domain,
    category: category,
    action: action,
  );
}

/// Datasource for auth API endpoints.
class AuthDatasource {
  AuthDatasource(this._dio);

  final Dio _dio;

  /// Sync user with core-api after OIDC authentication.
  ///
  /// Sends the OIDC access token to core-api, which validates it with Authentik
  /// and returns the user profile, roles, and preferences.
  Future<AuthSyncResponse> syncUser(String accessToken) async {
    final response = await _dio.post<Map<String, dynamic>>(
      '/auth/sync',
      data: {'access_token': accessToken},
    );

    return AuthSyncResponse.fromJson(response.data!);
  }

  /// Get current user profile via NPM forward auth.
  ///
  /// This endpoint reads X-authentik-* headers set by NPM forward auth.
  /// Returns user profile if authenticated via the proxy.
  /// Throws 401 if not authenticated or accessing directly.
  Future<AuthSyncResponse> getCurrentUser() async {
    final response = await _dio.get<Map<String, dynamic>>('/auth/users/me');
    return AuthSyncResponse.fromJson(response.data!);
  }

  /// Update user preferences.
  Future<UserPreferences> updatePreferences({
    String? theme,
    String? defaultRoom,
    Map<String, dynamic>? preferencesJson,
  }) async {
    final data = <String, dynamic>{};
    if (theme != null) data['theme'] = theme;
    if (defaultRoom != null) data['default_room'] = defaultRoom;
    if (preferencesJson != null) data['preferences_json'] = preferencesJson;

    final response = await _dio.patch<Map<String, dynamic>>(
      '/auth/users/me/preferences',
      data: data,
    );

    return UserPreferences.fromJson(response.data!);
  }
}

/// Provider for the auth datasource.
@riverpod
AuthDatasource authDatasource(Ref ref) {
  return AuthDatasource(ref.watch(coreApiClientProvider));
}