Revert "refactor: 清理租户API旧模块代码"

This reverts commit 992930a821.

src/Infrastructure/TakeoutSaaS.Infrastructure/Identity/Services/WeChatAuthService.cs

@@ -0,0 +1,79 @@
+using Microsoft.Extensions.Options;
+using System.Net.Http.Json;
+using System.Text.Json.Serialization;
+using TakeoutSaaS.Application.Identity.Abstractions;
+using TakeoutSaaS.Infrastructure.Identity.Options;
+using TakeoutSaaS.Shared.Abstractions.Constants;
+using TakeoutSaaS.Shared.Abstractions.Exceptions;
+
+namespace TakeoutSaaS.Infrastructure.Identity.Services;
+
+/// <summary>
+/// 微信 code2Session 实现
+/// </summary>
+public sealed class WeChatAuthService(HttpClient httpClient, IOptions<WeChatMiniOptions> options) : IWeChatAuthService
+{
+    private readonly WeChatMiniOptions _options = options.Value;
+
+    /// <summary>
+    /// 调用微信接口完成 code2Session。
+    /// </summary>
+    /// <param name="code">临时登录凭证 code。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>微信会话信息。</returns>
+    public async Task<WeChatSessionInfo> Code2SessionAsync(string code, CancellationToken cancellationToken = default)
+    {
+        // 1. 拼装请求地址
+        var requestUri = $"sns/jscode2session?appid={Uri.EscapeDataString(_options.AppId)}&secret={Uri.EscapeDataString(_options.Secret)}&js_code={Uri.EscapeDataString(code)}&grant_type=authorization_code";
+        using var response = await httpClient.GetAsync(requestUri, cancellationToken);
+        response.EnsureSuccessStatusCode();
+
+        // 2. 读取响应
+        var payload = await response.Content.ReadFromJsonAsync<WeChatSessionResponse>(cancellationToken: cancellationToken);
+        if (payload == null)
+        {
+            throw new BusinessException(ErrorCodes.Unauthorized, "微信登录失败：响应为空");
+        }
+
+        // 3. 校验错误码
+        if (payload.ErrorCode.HasValue && payload.ErrorCode.Value != 0)
+        {
+            var message = string.IsNullOrWhiteSpace(payload.ErrorMessage)
+                ? $"微信登录失败，错误码：{payload.ErrorCode}"
+                : payload.ErrorMessage;
+            throw new BusinessException(ErrorCodes.Unauthorized, message);
+        }
+
+        // 4. 校验必要字段
+        if (string.IsNullOrWhiteSpace(payload.OpenId) || string.IsNullOrWhiteSpace(payload.SessionKey))
+        {
+            throw new BusinessException(ErrorCodes.Unauthorized, "微信登录失败：返回数据无效");
+        }
+
+        // 5. 组装会话信息
+        return new WeChatSessionInfo
+        {
+            OpenId = payload.OpenId,
+            UnionId = payload.UnionId,
+            SessionKey = payload.SessionKey
+        };
+    }
+
+    private sealed class WeChatSessionResponse
+    {
+        [JsonPropertyName("openid")]
+        public string? OpenId { get; set; }
+
+        [JsonPropertyName("unionid")]
+        public string? UnionId { get; set; }
+
+        [JsonPropertyName("session_key")]
+        public string? SessionKey { get; set; }
+
+        [JsonPropertyName("errcode")]
+        public int? ErrorCode { get; set; }
+
+        [JsonPropertyName("errmsg")]
+        public string? ErrorMessage { get; set; }
+    }
+}