// food_delivery_service.dart — طبقة الاتصال بـ backend/food (جهة السائق/الموصّل)
import '../functions/crud.dart';
import '../../constant/links.dart';
import 'food_delivery_models.dart';

class FoodDeliveryApiResult<T> {
  final bool success;
  final T? data;
  final String message;
  FoodDeliveryApiResult(this.success, this.data, this.message);
}

class FoodDeliveryService {
  static String get _base => '${AppLink.server}/food';

  static Future<FoodDeliveryApiResult<bool>> toggleAvailability(bool enabled) async {
    final res = await CRUD().post(
      link: '$_base/courier/toggle_availability.php',
      payload: {'enabled': enabled.toString()},
    );
    if (res is Map && res['status'] == 'success') return FoodDeliveryApiResult(true, enabled, 'ok');
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  /// حالة السائق عند فتح التبويب — وضع التوصيل مخزَّن في Redis على الخادم،
  /// فلا يجوز افتراض "مغلق" محلياً وإلا ظهر التبديل مطفأً والعروض تصل فعلاً.
  static Future<FoodDeliveryApiResult<FoodCourierStatus>> getStatus() async {
    final res = await CRUD().post(link: '$_base/courier/status.php');
    final msg = _payload(res);
    if (msg != null) {
      return FoodDeliveryApiResult(true, FoodCourierStatus.fromJson(msg), 'ok');
    }
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<List<FoodDeliveryTask>>> getActiveTasks() async {
    final res = await CRUD().post(link: '$_base/courier/active.php');
    final msg = _payload(res);
    if (msg != null) {
      return FoodDeliveryApiResult(true, _list(msg['orders'], FoodDeliveryTask.fromJson), 'ok');
    }
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<List<FoodDeliveryOffer>>> getPendingOffers() async {
    final res = await CRUD().post(link: '$_base/courier/pending_offers.php');
    final msg = _payload(res);
    if (msg != null) {
      return FoodDeliveryApiResult(true, _list(msg['offers'], FoodDeliveryOffer.fromJson), 'ok');
    }
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<FoodOrderDetails>> getOrderDetails(int orderId) async {
    final res = await CRUD().post(
      link: '$_base/courier/order_details.php',
      payload: {'order_id': orderId.toString()},
    );
    final msg = _payload(res);
    if (msg != null && msg['order'] is Map) {
      return FoodDeliveryApiResult(
          true, FoodOrderDetails.fromJson(Map<String, dynamic>.from(msg['order'])), 'ok');
    }
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<FoodEarnings>> getEarnings() async {
    final res = await CRUD().post(link: '$_base/courier/earnings.php');
    final msg = _payload(res);
    if (msg != null) return FoodDeliveryApiResult(true, FoodEarnings.fromJson(msg), 'ok');
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<List<FoodHistoryEntry>>> getHistory({
    int limit = 20,
    int offset = 0,
  }) async {
    final res = await CRUD().post(
      link: '$_base/courier/history.php',
      payload: {'limit': limit.toString(), 'offset': offset.toString()},
    );
    final msg = _payload(res);
    if (msg != null) {
      return FoodDeliveryApiResult(true, _list(msg['orders'], FoodHistoryEntry.fromJson), 'ok');
    }
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<String>> respondToOffer(int orderId, bool accept) async {
    final res = await CRUD().post(
      link: '$_base/courier/offer_respond.php',
      payload: {'order_id': orderId.toString(), 'response': accept ? 'accept' : 'reject'},
    );
    final msg = _payload(res);
    if (msg != null) {
      return FoodDeliveryApiResult(true, msg['response']?.toString() ?? '', 'ok');
    }
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  /// بثّ موقع السائق للزبون أثناء المهمة. الخادم يرفضه بعد التسليم،
  /// وينتهي آخر موقع من Redis تلقائياً — لا تتبّع خارج نافذة العمل.
  static Future<void> sendLocation({
    required int orderId,
    required double lat,
    required double lng,
    double? heading,
  }) async {
    await CRUD().post(
      link: '$_base/courier/location.php',
      payload: {
        'order_id': orderId.toString(),
        'lat': lat.toString(),
        'lng': lng.toString(),
        if (heading != null) 'heading': heading.toStringAsFixed(0),
      },
    );
  }

  static Future<FoodDeliveryApiResult<void>> markPickedUp(int orderId) async {
    final res = await CRUD().post(
      link: '$_base/courier/picked_up.php',
      payload: {'order_id': orderId.toString()},
    );
    if (res is Map && res['status'] == 'success') return FoodDeliveryApiResult(true, null, 'ok');
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  static Future<FoodDeliveryApiResult<void>> markDelivered(int orderId) async {
    final res = await CRUD().post(
      link: '$_base/courier/delivered.php',
      payload: {'order_id': orderId.toString()},
    );
    if (res is Map && res['status'] == 'success') return FoodDeliveryApiResult(true, null, 'ok');
    return FoodDeliveryApiResult(false, null, _errMsg(res));
  }

  // كل ردود backend/food تأتي بغلاف {status, message:{...}} — نستخرج المحتوى مرة واحدة
  static Map<String, dynamic>? _payload(dynamic res) {
    if (res is Map && res['status'] == 'success' && res['message'] is Map) {
      return Map<String, dynamic>.from(res['message']);
    }
    return null;
  }

  static List<T> _list<T>(dynamic raw, T Function(Map<String, dynamic>) fromJson) {
    if (raw is! List) return <T>[];
    return raw.map((e) => fromJson(Map<String, dynamic>.from(e))).toList();
  }

  static String _errMsg(dynamic res) {
    if (res == 'no_internet') return 'تحقق من اتصالك بالإنترنت';
    if (res == 'token_expired') return 'انتهت الجلسة، حاول مجدداً';
    if (res is Map && res['message'] is String) return res['message'];
    return 'حدث خطأ، حاول مجدداً';
  }
}