import 'dart:async';
import 'dart:io';
import 'package:get/get.dart';
import 'package:in_app_purchase/in_app_purchase.dart';
import 'package:kaer_with_panels/app/services/iap/iap_pending_order_service.dart';
import 'package:kaer_with_panels/app/utils/kr_common_util.dart';
import 'package:kaer_with_panels/app/widgets/dialogs/hi_dialog.dart';
import 'package:kaer_with_panels/app/services/api_service/kr_subscribe_api.dart';
import 'package:kaer_with_panels/app/routes/app_pages.dart';

class KRIAPService extends GetxService {
  static KRIAPService get instance => Get.find<KRIAPService>();

  final KRSubscribeApi _kr_subscribeApi = KRSubscribeApi();
  final InAppPurchase _iap = InAppPurchase.instance;
  StreamSubscription<List<PurchaseDetails>>? _subscription;
// 增加标志位，防止多次初始化
  bool _hasStarted = false;

  @override
  void onInit() {
    super.onInit();
    // 不再这里自动启动，等待 Home 页面手动开启
  }

  /// 【外部调用】在 Home 页面加载完成后调用此方法
  void setup() {
    if (!Platform.isIOS) return;
    if (_hasStarted) return;
    _hasStarted = true;
    _startGlobalListening();
  }

  void _startGlobalListening() {
    print('💳 [IAPService] ========== 🚀 全局监听流已就绪 ==========');

    // 确保不会重复监听
    _subscription?.cancel();

    _subscription = _iap.purchaseStream.listen(
      _handleIapUpdates,
      onDone: () => _subscription?.cancel(),
      onError: (error) {
        print('💳 [IAPService] ❌ Stream Error: $error');
        // 如果发生错误，可以尝试重启流
      },
    );
  }

  // 1. 监听回调：只负责状态分流
  void _handleIapUpdates(List<PurchaseDetails> purchases) async {
    final pendingOrderNo = await IAPPendingOrderService.getPendingOrderNo();

    // 如果没有本地挂起的订单号，说明不是通过 App 正常发起的支付（或是已处理完的补单）
    if (pendingOrderNo == null || pendingOrderNo.isEmpty) return;

    for (final p in purchases) {
      print('🔄 [IAPService] 处理状态: ${p.status} | ID: ${p.purchaseID}');

      if (p.status == PurchaseStatus.pending) continue;

      if (p.status == PurchaseStatus.error) {
        if (p.pendingCompletePurchase) await _iap.completePurchase(p);
        KRCommonUtil.kr_showToast('购买失败');
        KRCommonUtil.kr_hideLoading();
        continue;
      }

      if (p.status == PurchaseStatus.purchased || p.status == PurchaseStatus.restored) {
        // 核心：跳转到统一验证逻辑
        _verifyWithServer(p, pendingOrderNo);
      }
    }
  }

  // 2. 统一验证逻辑：负责与后端交互、补单、UI 引导
  Future<void> _verifyWithServer(PurchaseDetails p, String orderNo) async {
    final String jwsData = p.verificationData.serverVerificationData;

    if (jwsData.isEmpty) {
      print('❌ [IAPService] JWS 数据为空，跳过验证');
      if (p.pendingCompletePurchase) {
        await InAppPurchase.instance.completePurchase(p);
      }
      KRCommonUtil.kr_hideLoading();
      return;
    }

    KRCommonUtil.kr_showLoading(message: '正在激活会员权益...');
    bool ok = false;

    try {
      // 根据状态选择对应的后端接口
      if (p.status == PurchaseStatus.purchased || p.status == PurchaseStatus.restored) {
        final either = await _kr_subscribeApi.kr_attachAppleIapTransaction(jwsData, orderNo);
        either.fold((e) => print('❌ [IAPService] 支付激活失败: ${e.msg}'), (v) => ok = true);
      } else {
        // 注意：restore 接口如果后端要求传 JWS，这里保持一致
        // final either = await _kr_subscribeApi.kr_restoreAppleIapTransaction(jwsData, orderNo);
        // either.fold((e) => print('❌ [IAPService] 恢复激活失败: ${e.msg}'), (v) => ok = true);
      }
    } catch (e) {
      print('🌐 [IAPService] 网络请求异常');
    }

    if (ok) {
      await _finalizeTransaction(p, orderNo);
    } else {
      _handleVerificationFailure(p, orderNo);
    }
  }

  // 3. 验证成功后的收尾工作
  Future<void> _finalizeTransaction(PurchaseDetails p, String orderNo) async {
    print('✅ [IAPService] 验证成功，清理流程');

    // I. 结束苹果事务（关键：防止重复推送）
    if (p.pendingCompletePurchase) {
      await _iap.completePurchase(p);
    }

    // II. 清理本地拦截订单号
    await IAPPendingOrderService.clearPendingOrderNo();
    KRCommonUtil.kr_hideLoading();

    // III. 跳转结果页
    // 如果已经在结果页了就不跳，或者根据路由判断
    if (!Get.currentRoute.contains(Routes.KR_ORDER_STATUS)) {
      Get.offNamed(
        Routes.KR_ORDER_STATUS,
        arguments: {
          'order': orderNo,
          'payment_type': 'apple_iap',
          'checkout_type': 'ipa',
        },
      );
    }
  }

  // 4. 验证失败后的重试引导
  void _handleVerificationFailure(PurchaseDetails p, String orderNo) {
    KRCommonUtil.kr_hideLoading();
    HIDialog.show(
      title: '激活失败',
      message: '您的支付已成功，但由于网络原因未能开启权益。',
      confirmText: '重试激活',
      cancelText: '关闭',
      barrierDismissible: false,
      preventBackDismiss: true,
      onConfirm: () {
        // 💡 重点：直接重新调用验证逻辑，不重复触发监听流
        _verifyWithServer(p, orderNo);
      },
    );
  }

  // 5. 手动触发（用于 UI 上的恢复购买按钮）
  Future<void> retryUnfinishedTransactions() async {
    try {
      KRCommonUtil.kr_showLoading(message: '正在查找未完成订单...');
      await _iap.restorePurchases();
      // 如果 5 秒后没触发流，隐藏 loading
      Future.delayed(const Duration(seconds: 5), () => KRCommonUtil.kr_hideLoading());
    } catch (e) {
      KRCommonUtil.kr_hideLoading();
      KRCommonUtil.kr_showToast("请求失败，请稍后重试");
    }
  }

  @override
  void onClose() {
    _subscription?.cancel();
    super.onClose();
  }
}