pangolin/client/test/unit/payment_flow_test.dart

import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:pangolin_vpn/models/payment.dart';
import 'package:pangolin_vpn/services/auth_api.dart';
import 'package:pangolin_vpn/services/payment_api.dart';
import 'package:pangolin_vpn/state/payment_provider.dart';

class _FakePaymentApi implements PaymentApi {
  _FakePaymentApi();
  int createCalls = 0, cancelCalls = 0, statusCalls = 0;
  bool activated = false;
  Exception? retryError;
  String lastMethod = '';

  @override
  Future<List<PayCatalogItem>> catalog() async => const [];

  @override
  Future<PayOrder> createOrder({required String sku, required String method, Map<String, String>? metadata}) async {
    createCalls++;
    lastMethod = method;
    return PayOrder(
        orderNo: 'pay$createCalls',
        session: PaySession(renderType: method == 'crypto' ? 'crypto_address' : 'redirect', payload: const {'url': 'https://x'}, expiresAt: null));
  }

  @override
  Future<PayOrderStatus> orderStatus(String orderNo) async {
    statusCalls++;
    return PayOrderStatus(orderNo: orderNo, payStatus: activated ? 'succeeded' : 'pending', activated: activated, expiresAt: null);
  }

  @override
  Future<PayOrder> retry(String orderNo, {required String method, Map<String, String>? metadata}) async {
    if (retryError != null) throw retryError!;
    return PayOrder(orderNo: orderNo, session: PaySession(renderType: 'redirect', payload: const {'url': 'https://y'}, expiresAt: null));
  }

  @override
  Future<void> cancel(String orderNo) async {
    cancelCalls++;
  }
}

ProviderContainer _container(_FakePaymentApi api) {
  final c = ProviderContainer(overrides: [paymentApiProvider.overrideWithValue(api)]);
  addTearDown(c.dispose);
  return c;
}

void main() {
  const item = PayCatalogItem(sku: 'pro_month', plan: 'pro', days: 31, priceMinor: 2999, currency: 'CNY');

  test('start → awaitingPayment,pollOnce 到 activated 变 succeeded', () async {
    final api = _FakePaymentApi();
    final c = _container(api);
    final ctl = c.read(paymentFlowProvider.notifier);
    await ctl.start(item, 'crypto');
    expect(c.read(paymentFlowProvider).phase, PaymentPhase.awaitingPayment);
    await ctl.pollOnce();
    expect(c.read(paymentFlowProvider).phase, PaymentPhase.awaitingPayment);
    api.activated = true;
    await ctl.pollOnce();
    expect(c.read(paymentFlowProvider).phase, PaymentPhase.succeeded);
  });

  test('switchMethod 遇 CURRENCY_MISMATCH → cancel 旧单 + 新 method 重新下单', () async {
    final api = _FakePaymentApi();
    final c = _container(api);
    final ctl = c.read(paymentFlowProvider.notifier);
    await ctl.start(item, 'crypto');
    api.retryError = const AuthApiException(
        statusCode: 409, messageZh: 'x', messageEn: 'x', code: 'CURRENCY_MISMATCH');
    await ctl.switchMethod('alipay');
    expect(api.cancelCalls, 1);
    expect(api.createCalls, 2, reason: '换币种必须新单(pay 契约)');
    expect(api.lastMethod, 'alipay');
    expect(c.read(paymentFlowProvider).order?.orderNo, 'pay2');
  });
}