import 'dart:io';
import 'package:injectable/injectable.dart';
import 'package:mnemo_cards_backend/api/di/injector.dart';
import 'package:mnemo_cards_backend/user/user_manager.dart';
import 'package:shelf/shelf.dart';
import 'package:shelf/shelf_io.dart' as shelf_io;
import 'package:shelf_router/shelf_router.dart';

// import 'v2/ads_api_v2.dart'; // disabled
import 'v2/admin_analytics_api_v2.dart';
import 'v2/admin_auth_api_v2.dart';
import 'v2/admin_cards_api_v2.dart';
import 'v2/admin_packs_api_v2.dart';
// import 'v2/admin_users_api_v2.dart'; // disabled
import 'v2/auth_api_v2.dart';
import 'v2/discounts_api_v2.dart';
// import 'v2/games_api_v2.dart'; // disabled
// import 'v2/packs_api_v2.dart'; // disabled
// import 'v2/purchases_api_v2.dart'; // disabled
import 'v2/promocodes_api_v2.dart';
import 'v2/subscriptions_api_v2.dart';
import 'v2/tasks_api_v2.dart';
import 'v2/tests_api_v2.dart';
// import 'v2/users_api_v2.dart'; // disabled
// import 'v2/telegram_bot_api_v2.dart'; // disabled
import 'v2/authorize_v2.dart';
import 'v2/telegram_bot_auth_middleware.dart';
import 'v2/jwt_service.dart';
import 'authorize/access_middleware.dart';
import 'package:mnemo_cards_backend/packs/pack_manager.dart';
import 'package:mnemo_cards_backend/statistics/session_tracking_middleware.dart';
import 'package:mnemo_cards_backend/statistics/session_tracker.dart';

@lazySingleton
class MnemoShelf {
  final UserManager userManager;

  MnemoShelf(this.userManager);

  Future<void> initV2() async {
    // Чтение переменных окружения вместо CLI аргументов
    final addressArg = Platform.environment['SERVER_ADDRESS'];
    final portArg = Platform.environment['PORT'];
    // Используем InternetAddress напрямую для правильной работы с bind
    final address = addressArg != null && addressArg != '0.0.0.0'
        ? InternetAddress(addressArg)
        : InternetAddress.anyIPv4;
    final port = int.tryParse(portArg ?? '') ?? 3000;

    // V2 APIs (new RESTful API with OAuth2/JWT)
    final v2Router = Router();

    // Add routers individually to avoid type issues
    v2Router.mount('/', getIt.get<AuthApiV2>().router);
    v2Router.mount('/', getIt.get<AdminAuthApiV2>().router);
    v2Router.mount('/', getIt.get<AdminAnalyticsApiV2>().router);
    v2Router.mount('/', getIt.get<AdminCardsApiV2>().router);
    v2Router.mount('/', getIt.get<AdminPacksApiV2>().router);
    // v2Router.mount('/', getIt.get<PacksApiV2>().router); // disabled
    v2Router.mount('/', getIt.get<TestsApiV2>().router);
    // v2Router.mount('/', getIt.get<GamesApiV2>().router); // disabled
    // v2Router.mount('/', getIt.get<PurchasesApiV2>().router); // disabled
    v2Router.mount('/', getIt.get<PromocodesApiV2>().router);
    v2Router.mount('/', getIt.get<SubscriptionsApiV2>().router);
    v2Router.mount('/', getIt.get<DiscountsApiV2>().router);
    v2Router.mount('/', getIt.get<TasksApiV2>().handler);

    // Note: rootRouter is not used because we manually route to v1/v2 handlers
    // for different authentication middleware. Keeping for reference.
    // final rootRouter = Router()
    //   ..mount('/', v1Router) // Legacy v1 APIs
    //   ..mount('/api/v2', v2Router); // New v2 APIs
    // ..mount(
    //   '/swagger',
    //   SwaggerUI('public/open_api.yaml', title: 'Api'),
    // )
    // ..mount('/', createStaticHandler('public'));

    // Configure a pipeline with proper CORS configuration
    final corsConfig = {
      'Access-Control-Allow-Origin': '*', // Разрешаем все домены для гибкости
      'Access-Control-Allow-Methods':
          'GET, POST, PUT, DELETE, PATCH, HEAD, OPTIONS',
      'Access-Control-Allow-Headers':
          'Origin, Content-Type, Accept, Authorization, user_token, request_token, app_version, X-API-Key',
      'Access-Control-Expose-Headers': 'Authorization',
      'Access-Control-Max-Age': '86400',
    };

    // CORS middleware that handles preflight requests
    Middleware corsMiddleware() {
      return (Handler innerHandler) {
        return (Request request) async {
          // Handle preflight requests
          if (request.method == 'OPTIONS') {
            return Response.ok('', headers: corsConfig);
          }

          // Process the request and add CORS headers to response
          final response = await innerHandler(request);
          return response.change(headers: {
            ...response.headers,
            ...corsConfig,
          });
        };
      };
    }

    final v2Handler = Pipeline()
        .addMiddleware(corsMiddleware())
        .addMiddleware(logRequests(logger: logger('v2')))
        .addMiddleware(telegramBotAuthMiddleware())
        .addMiddleware(
            authorizeV2(getIt.get<UserManager>(), getIt.get<JwtService>()))
        .addMiddleware(accessMiddleware(
            buildAccessService(getIt.get<PackManager>()),
            getIt.get<PackManager>()))
        .addMiddleware(sessionTrackingMiddleware(getIt.get<SessionTracker>()))
        .addHandler(v2Router);

    final rootRouter = Router()
      ..get('/health', (Request request) {
        // Простой эндпоинт для healthcheck - всегда отвечает OK
        // Не используем async для максимальной простоты и скорости
        return Response.ok(
          'OK',
          headers: {
            'Content-Type': 'text/plain; charset=utf-8',
            ...corsConfig,
          },
        );
      })
      ..mount('/api/v2', v2Handler)
      ..all('/<ignored|.*>', (Request request) async {
        if (request.method == 'OPTIONS') {
          return Response.ok('', headers: corsConfig);
        }
        return Response.notFound('Not Found', headers: corsConfig);
      });

    final handler = rootRouter.call;

    // Запуск HTTP сервера (HTTPS обрабатывается на уровне reverse proxy в Coolify)
    final server = await _createServer(
      handler,
      address,
      port,
      poweredByHeader: null,
      shared: true,
    );

    print('Serving app at http://${server.address.address}:${server.port}');
    print('Server listening on http://${server.address.address}:${server.port}');
  }

  logger(String tag) => (String msg, bool isError) {
        if (isError) {
          print('[ERROR][$tag] $msg');
        } else {
          print('[$tag] $msg');
        }
      };

  Future<HttpServer> _createServer(
    Handler handler,
    InternetAddress address,
    int port, {
    int? backlog,
    bool shared = false,
    String? poweredByHeader = 'Dart with package:shelf',
  }) async {
    backlog ??= 0;
    final server = await HttpServer.bind(
      address,
      port,
      backlog: backlog,
      shared: shared,
    );
    // Запускаем обработку запросов (неблокирующая операция)
    // serveRequests запускает обработку запросов в фоне и возвращает управление сразу
    shelf_io.serveRequests(server, handler, poweredByHeader: poweredByHeader);
    // Даем серверу небольшое время на инициализацию обработчика запросов
    await Future.delayed(const Duration(milliseconds: 100));
    print('✅ Server bound and ready to accept connections on ${server.address.address}:${server.port}');
    return server;
  }
}