新增厂商 Provider

namespace Bitzsoft.Integrations.Payment.PayPal;

/// <summary>PayPal 支付连接配置</summary>
public sealed class PayPalOptions
{
    /// <summary>PayPal 应用 Client Id</summary>
    public string ClientId { get; set; } = string.Empty;

    /// <summary>PayPal 应用 Secret</summary>
    public string ClientSecret { get; set; } = string.Empty;

    /// <summary>网关地址（正式 / 沙箱）</summary>
    public string BaseUrl { get; set; } = "https://api-m.paypal.com";

    /// <summary>异步通知 Webhook Id</summary>
    public string? WebhookId { get; set; }

    /// <summary>HTTP 请求超时时间</summary>
    public TimeSpan Timeout { get; set; } = TimeSpan.FromSeconds(30);

    /// <summary>命名 HTTP 客户端标识，用于 IHttpClientFactory 匹配</summary>
    public string HttpClientName { get; set; } = nameof(PayPalPaymentProvider); // ① 与 Provider 类名对齐
}

namespace Bitzsoft.Integrations.Payment.PayPal;

/// <summary>PayPal 配置提供器接口</summary>
internal interface IPayPalConfigProvider : IPaymentConfigProvider<PayPalOptions>
{
}

using Microsoft.Extensions.Options;

namespace Bitzsoft.Integrations.Payment.PayPal;

/// <summary>PayPal 默认配置提供器</summary>
internal sealed class PayPalConfigProvider : IPayPalConfigProvider
{
    private readonly IOptions<PayPalOptions> _options;

    public PayPalConfigProvider(IOptions<PayPalOptions> options) => _options = options;

    public PayPalOptions Current => _options.Value;
    public string HttpClientName => _options.Value.HttpClientName;
}

using System.Net.Http.Headers;
using System.Text.Json;

namespace Bitzsoft.Integrations.Payment.PayPal.Internal;

/// <summary>PayPal HTTP 客户端，封装 OAuth2 token 与 JSON 请求</summary>
internal sealed class PayPalHttpClient
{
    private readonly HttpClient _httpClient;
    private readonly IPayPalConfigProvider _config;
    private string? _accessToken;
    private DateTimeOffset _tokenExpiresAt;

    public PayPalHttpClient(IHttpClientFactory httpClientFactory, IPayPalConfigProvider config)
    {
        var options = config.Current;
        CompatibilityArgument.ThrowIfNullOrEmpty(options.ClientId);
        CompatibilityArgument.ThrowIfNullOrEmpty(options.ClientSecret);
        CompatibilityArgument.ThrowIfNullOrEmpty(options.BaseUrl);

        _config = config;
        _httpClient = httpClientFactory.CreateClient(config.HttpClientName); // ① 命名客户端
        _httpClient.Timeout = options.Timeout;
    }

    public async Task<JsonElement> PostAsync(string path, object body, CancellationToken ct = default)
    {
        await EnsureTokenAsync(ct).ConfigureAwait(false);

        using var content = JsonContent.Create(body);
        _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", _accessToken);

        using var response = await _httpClient.PostAsync($"{_config.Current.BaseUrl}{path}", content, ct)
            .ConfigureAwait(false);

        var text = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
        if (!response.IsSuccessStatusCode)
        {
            // ② 非 2xx 抛领域异常，由 Provider 统一捕获转 Result
            throw new PaymentException(
                PaymentProviderCode.PayPal,
                $"HTTP_{(int)response.StatusCode}",
                $"PayPal 请求失败: HTTP {(int)response.StatusCode}");
        }

        return string.IsNullOrEmpty(text) ? default : JsonDocument.Parse(text).RootElement.Clone();
    }

    private async Task EnsureTokenAsync(CancellationToken ct)
    {
        if (_accessToken is not null && DateTimeOffset.UtcNow < _tokenExpiresAt)
            return;

        // ③ client_credentials 换 token，缓存到过期前
        using var form = new FormUrlEncodedContent(new[]
        {
            new KeyValuePair<string, string>("grant_type", "client_credentials"),
        });
        // ... 用 Basic auth 换 token，略
        _accessToken = "EC-...";
        _tokenExpiresAt = DateTimeOffset.UtcNow.AddMinutes(45);
    }
}

using System.Text.Json;
using Bitzsoft.Integrations.Payment.PayPal.Internal;
using Microsoft.Extensions.Logging;

namespace Bitzsoft.Integrations.Payment.PayPal;

/// <summary>PayPal 支付实现</summary>
public sealed class PayPalPaymentProvider : IPaymentProvider
{
    private readonly PayPalHttpClient _httpClient;
    private readonly IPayPalConfigProvider _config;
    private readonly ILogger<PayPalPaymentProvider> _logger;

    internal PayPalPaymentProvider( // ① internal ctor，禁止外部 new
        PayPalHttpClient httpClient,
        IPayPalConfigProvider config,
        ILogger<PayPalPaymentProvider> logger)
    {
        _httpClient = httpClient;
        _config = config;
        _logger = logger;
    }

    public string Code => PaymentProviderCode.PayPal; // ② 复用抽象层常量

    public async Task<PaymentResult<PaymentStatusResult>> QueryStatusAsync(
        string outTradeNo, CancellationToken ct = default)
    {
        CompatibilityArgument.ThrowIfNullOrEmpty(outTradeNo);

        _logger.LogInformation("PayPal 查询订单状态: {OutTradeNo}", outTradeNo);

        JsonElement json;
        try
        {
            json = await _httpClient.PostAsync("/v2/checkout/orders", new { }, ct).ConfigureAwait(false);
        }
        catch (PaymentException ex) // ③ 先捕获领域异常，保留原始错误码
        {
            _logger.LogWarning("PayPal 查询订单失败: {Code} - {Msg}", ex.ErrorCode, ex.ProviderMessage);
            return PaymentResult<PaymentStatusResult>.Fail(ex.ErrorCode ?? "QUERY_FAILED", ex.ProviderMessage ?? ex.Message);
        }
        catch (HttpRequestException ex) // ④ 再捕获网络异常，归一为 HTTP_ERROR
        {
            _logger.LogWarning(ex, "PayPal 查询订单网络异常");
            return PaymentResult<PaymentStatusResult>.Fail("HTTP_ERROR", ex.Message);
        }

        var statusResult = new PaymentStatusResult
        {
            OutTradeNo = outTradeNo,
            TradeNo = json.GetProperty("id").GetString(),
            Status = MapStatus(json.GetProperty("status").GetString()),
            // ... 其余字段映射
        };

        return PaymentResult<PaymentStatusResult>.Success(statusResult);
    }

    // CreateOrderAsync / CloseOrderAsync / RefundAsync / VerifyCallbackAsync 同结构，略
    private static PaymentStatus MapStatus(string? s) => s switch
    {
        "COMPLETED" => PaymentStatus.Success,
        "APPROVED" => PaymentStatus.Pending,
        _ => PaymentStatus.Pending,
    };
}

using Bitzsoft.Integrations.Payment.PayPal;
using Bitzsoft.Integrations.Payment.PayPal.Internal;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Logging;

namespace Microsoft.Extensions.DependencyInjection; // ① 关键：放这个命名空间

/// <summary>PayPal 支付服务注册扩展</summary>
public static class PayPalServiceCollectionExtensions
{
    /// <summary>从委托注册 PayPal 支付服务</summary>
    public static IServiceCollection AddBitzsoftPayPalPayment(
        this IServiceCollection services, Action<PayPalOptions> configure)
    {
        CompatibilityArgument.ThrowIfNull(configure);

        var options = new PayPalOptions();
        configure(options);

        services.AddHttpClient(options.HttpClientName).AddRequestLogging(options.HttpClientName); // ② 挂审计日志
        services.Configure(configure);
        services.TryAddSingleton<IPayPalConfigProvider, PayPalConfigProvider>();
        RegisterProvider(services);

        return services;
    }

    /// <summary>从 IConfiguration 注册 PayPal 支付服务</summary>
    public static IServiceCollection AddBitzsoftPayPalPayment(
        this IServiceCollection services, IConfiguration configuration,
        string sectionKey = "PayPal")
    {
        CompatibilityArgument.ThrowIfNull(configuration);

        var options = new PayPalOptions();
        configuration.GetSection(sectionKey).Bind(options);

        services.AddHttpClient(options.HttpClientName).AddRequestLogging(options.HttpClientName);
        services.Configure<PayPalOptions>(configuration.GetSection(sectionKey));
        services.TryAddSingleton<IPayPalConfigProvider, PayPalConfigProvider>();
        RegisterProvider(services);

        return services;
    }

    private static void RegisterProvider(IServiceCollection services)
    {
        services.TryAddTransient<PayPalHttpClient>();
        services.AddIntegrationProviderCapability<IPaymentProvider, PayPalPaymentProvider>( // ③ 提交 Descriptor + 实现
            PayPalProviderDescriptor.Instance,
            sp => new PayPalPaymentProvider(
                sp.GetRequiredService<PayPalHttpClient>(),
                sp.GetRequiredService<IPayPalConfigProvider>(),
                sp.GetRequiredService<ILogger<PayPalPaymentProvider>>()));
    }
}

namespace Bitzsoft.Integrations.Payment.PayPal;

internal static class PayPalProviderDescriptor
{
    public static readonly IntegrationProviderDescriptor Instance = new(
        providerId: PaymentProviderCode.PayPal, // ① 与抽象层常量一致
        displayName: "PayPal",
        domain: "Payment",
        capabilityTypes: new[] { typeof(IPaymentProvider) },
        stability: IntegrationProviderStability.Preview, // ② 新接入先标 Preview，稳定后升 Stable
        vendor: "PayPal",
        apiVersion: "v2",
        authenticationType: "OAuth2",
        regions: new[] { "Global" },
        environments: new[] { "Production", "Sandbox" });
}

public static IServiceCollection AddBitzsoftPaymentAll(
    this IServiceCollection services, IConfiguration configuration,
    string sectionKey = "Payment")
{
    var section = configuration.GetSection(sectionKey);

    if (section.GetSection("Alipay").Exists())
        services.AddBitzsoftAlipayPayment(configuration, $"{sectionKey}:Alipay");
    if (section.GetSection("WeChatPay").Exists())
        services.AddBitzsoftWeChatPayPayment(configuration, $"{sectionKey}:WeChatPay");
    if (section.GetSection("Stripe").Exists())
        services.AddBitzsoftStripePayment(configuration, $"{sectionKey}:Stripe");
    if (section.GetSection("PayPal").Exists()) // ② 新增条件注册
        services.AddBitzsoftPayPalPayment(configuration, $"{sectionKey}:PayPal");

    return services;
}

[Fact]
public async Task QueryStatus_PaypalBusinessError_PreservesErrorCode()
{
    // ① 构造一个返回 HTTP 400 的 HttpMessageHandler
    var handler = new StubHandler(System.Net.HttpStatusCode.BadRequest, "{}");
    var services = new ServiceCollection();
    services.AddHttpClient(nameof(PayPalPaymentProvider)).AddRequestLogging(nameof(PayPalPaymentProvider))
        .ConfigurePrimaryHttpMessageHandler(() => handler);
    services.AddBitzsoftPayPalPayment(_ => _.ClientId = "c"); // 其余配置略

    var sp = services.BuildServiceProvider();
    var provider = sp.GetRequiredService<IPaymentProvider>();

    var result = await provider.QueryStatusAsync("ORDER-1");

    Assert.False(result.IsSuccess);
    Assert.StartsWith("HTTP_", result.ErrorCode); // ② 厂商错误码透传
}

[Fact]
public void Payment_All_Registers_PayPal_When_Configured()
{
    var config = new ConfigurationBuilder()
        .AddInMemoryCollection(new Dictionary<string, string?>
        {
            ["Payment:PayPal:ClientId"] = "test",
        })
        .Build();

    var services = new ServiceCollection();
    services.AddBitzsoftPaymentAll(config); // ③ 聚合包注册
    var sp = services.BuildServiceProvider(validateScopes: true);

    var resolver = sp.GetRequiredService<IIntegrationProviderResolver<IPaymentProvider>>();
    Assert.True(resolver.TryResolve("PayPal", out _)); // ④ 可按 ID 解析
}