import 'dart:async';

import 'package:fluwx/fluwx.dart';
import 'package:tobias/tobias.dart';

import '../core/config/app_config.dart';
import 'payment_service.dart';

/// 支付宝/微信原生 SDK 调起封装（《03-接口文档》8.2 pay_params）
///
/// 服务端配置了商户密钥时 pay_params 为真实调起参数，此处调起原生 SDK；
/// 未配置（dev）时服务端返回 dev_mock 占位，调用方应以轮询兜底代替调起。
enum PayLaunchResult {
  /// 渠道回调成功（仍需以服务端查单为准，避免客户端伪造）
  success,

  /// 用户主动取消
  canceled,

  /// 调起失败（未安装 App / 参数缺失 / SDK 报错）
  failed,

  /// pay_params 无有效调起参数（服务端未配置商户密钥）
  unsupported,
}

class PayLauncher {
  PayLauncher._();

  static final _fluwx = Fluwx();

  /// 微信调起等待回调的最长时间
  static const _wechatTimeout = Duration(minutes: 5);

  /// 支付宝调起：order_string 直接交给 SDK
  static Future<PayLaunchResult> launchAlipay(RechargeOrderInfo order) async {
    final orderString = order.payParams['order_string'] as String?;
    if (orderString == null || orderString.isEmpty) {
      return PayLaunchResult.unsupported;
    }
    try {
      final result = await Tobias().pay(orderString);
      return _mapAlipayStatus(result['resultStatus'] as String?);
    } catch (_) {
      return PayLaunchResult.failed;
    }
  }

  /// 微信调起：registerApi → pay → 等待 SDK 回调
  static Future<PayLaunchResult> launchWechat(RechargeOrderInfo order) async {
    final params = order.payParams;
    final appId = params['appid'] as String?;
    final partnerId = params['partnerid'] as String?;
    final prepayId = params['prepayid'] as String?;
    final packageValue = params['package'] as String?;
    final nonceStr = params['noncestr'] as String?;
    final sign = params['sign'] as String?;
    final timestamp = int.tryParse('${params['timestamp']}');
    if (appId == null ||
        appId.isEmpty ||
        partnerId == null ||
        partnerId.isEmpty ||
        prepayId == null ||
        prepayId.isEmpty ||
        packageValue == null ||
        packageValue.isEmpty ||
        nonceStr == null ||
        nonceStr.isEmpty ||
        sign == null ||
        sign.isEmpty ||
        timestamp == null) {
      return PayLaunchResult.unsupported;
    }

    final completer = Completer<PayLaunchResult>();
    final cancelable = _fluwx.addSubscriber((response) {
      if (response is WeChatPaymentResponse && !completer.isCompleted) {
        completer.complete(_mapWechatErrCode(response.errCode));
      }
    });

    try {
      await _fluwx.registerApi(
        appId: appId,
        universalLink: AppConfig.wechatUniversalLink.isEmpty
            ? null
            : AppConfig.wechatUniversalLink,
      );
      final sent = await _fluwx.pay(
        which: Payment(
          appId: appId,
          partnerId: partnerId,
          prepayId: prepayId,
          packageValue: packageValue,
          nonceStr: nonceStr,
          timestamp: timestamp,
          sign: sign,
        ),
      );
      if (!sent) return PayLaunchResult.failed;
      return await completer.future.timeout(
        _wechatTimeout,
        onTimeout: () => PayLaunchResult.failed,
      );
    } catch (_) {
      return PayLaunchResult.failed;
    } finally {
      cancelable.cancel();
    }
  }

  /// 按支付方式分发（1支付宝 2微信）
  static Future<PayLaunchResult> launch(RechargeOrderInfo order) {
    return switch (order.payMethod) {
      1 => launchAlipay(order),
      2 => launchWechat(order),
      _ => Future.value(PayLaunchResult.unsupported),
    };
  }

  /// 支付宝 resultStatus：9000成功 6001用户取消 8000/8001处理中 其余失败
  static PayLaunchResult _mapAlipayStatus(String? status) {
    return switch (status) {
      '9000' => PayLaunchResult.success,
      '6001' => PayLaunchResult.canceled,
      '8000' || '8001' => PayLaunchResult.success, // 处理中，交由服务端查单确认
      _ => PayLaunchResult.failed,
    };
  }

  /// 微信 errCode：0成功 -2用户取消 其余失败
  static PayLaunchResult _mapWechatErrCode(int? errCode) {
    return switch (errCode) {
      0 => PayLaunchResult.success,
      -2 => PayLaunchResult.canceled,
      _ => PayLaunchResult.failed,
    };
  }
}