flutter_paydemo/lib/service/platform/alipay_io.dart

/// 支付宝 Native 实现（Android/iOS，封装 alipay_kit）
library;

import 'dart:async';

import 'package:alipay_kit/alipay_kit.dart';

/// 支付宝支付结果
class AlipayPayResult {
  final int? resultStatus;
  final String? memo;

  AlipayPayResult({this.resultStatus, this.memo});

  bool get isSuccessful => resultStatus == 9000;
  bool get isCancelled => resultStatus == 6001;
}

/// 支付宝封装（App 支付）
class AlipayFlow {
  AlipayFlow._();

  static final AlipayFlow instance = AlipayFlow._();

  StreamSubscription<AlipayResp>? _sub;

  /// 拉起支付宝 App 支付
  /// [orderStr] 后端 sdkExecute 生成的调起字符串
  ///
  /// alipay_kit 的支付结果是异步流（payResp），需先订阅再发起，避免丢失结果。
  Future<AlipayPayResult> pay(String orderStr) async {
    final completer = Completer<AlipayPayResult>();

    // 先订阅结果流
    await _sub?.cancel();
    _sub = AlipayKitPlatform.instance.payResp().listen((resp) {
      if (!completer.isCompleted) {
        completer.complete(
          AlipayPayResult(resultStatus: resp.resultStatus, memo: resp.memo),
        );
      }
    });

    // 发起支付（原生弹起支付宝；结果经 payResp 流返回）
    await AlipayKitPlatform.instance.pay(orderInfo: orderStr);

    // 等待结果（超时兜底，避免永远阻塞）
    return completer.future.timeout(
      const Duration(seconds: 90),
      onTimeout: () => AlipayPayResult(resultStatus: 6002, memo: '支付超时'),
    );
  }
}