feat: 实现租户管理及套餐流程

src/Application/TakeoutSaaS.Application/App/Tenants/Handlers/RegisterTenantCommandHandler.cs

@@ -0,0 +1,88 @@
+using MediatR;
+using Microsoft.Extensions.Logging;
+using TakeoutSaaS.Application.App.Tenants.Commands;
+using TakeoutSaaS.Application.App.Tenants.Dto;
+using TakeoutSaaS.Domain.Tenants.Entities;
+using TakeoutSaaS.Domain.Tenants.Enums;
+using TakeoutSaaS.Domain.Tenants.Repositories;
+using TakeoutSaaS.Shared.Abstractions.Constants;
+using TakeoutSaaS.Shared.Abstractions.Exceptions;
+using TakeoutSaaS.Shared.Abstractions.Ids;
+
+namespace TakeoutSaaS.Application.App.Tenants.Handlers;
+
+/// <summary>
+/// 租户注册处理器。
+/// </summary>
+public sealed class RegisterTenantCommandHandler(
+    ITenantRepository tenantRepository,
+    IIdGenerator idGenerator,
+    ILogger<RegisterTenantCommandHandler> logger)
+    : IRequestHandler<RegisterTenantCommand, TenantDto>
+{
+    private readonly ITenantRepository _tenantRepository = tenantRepository;
+    private readonly IIdGenerator _idGenerator = idGenerator;
+    private readonly ILogger<RegisterTenantCommandHandler> _logger = logger;
+
+    /// <inheritdoc />
+    public async Task<TenantDto> Handle(RegisterTenantCommand request, CancellationToken cancellationToken)
+    {
+        if (request.DurationMonths <= 0)
+        {
+            throw new BusinessException(ErrorCodes.BadRequest, "订阅时长必须大于 0");
+        }
+
+        if (await _tenantRepository.ExistsByCodeAsync(request.Code, cancellationToken))
+        {
+            throw new BusinessException(ErrorCodes.Conflict, $"租户编码 {request.Code} 已存在");
+        }
+
+        var now = DateTime.UtcNow;
+        var effectiveFrom = request.EffectiveFrom ?? now;
+        var effectiveTo = effectiveFrom.AddMonths(request.DurationMonths);
+
+        var tenant = new Tenant
+        {
+            Id = _idGenerator.NextId(),
+            Code = request.Code.Trim(),
+            Name = request.Name,
+            ShortName = request.ShortName,
+            Industry = request.Industry,
+            ContactName = request.ContactName,
+            ContactPhone = request.ContactPhone,
+            ContactEmail = request.ContactEmail,
+            Status = TenantStatus.PendingReview,
+            EffectiveFrom = effectiveFrom,
+            EffectiveTo = effectiveTo
+        };
+
+        var subscription = new TenantSubscription
+        {
+            Id = _idGenerator.NextId(),
+            TenantId = tenant.Id,
+            TenantPackageId = request.TenantPackageId,
+            EffectiveFrom = effectiveFrom,
+            EffectiveTo = effectiveTo,
+            NextBillingDate = effectiveTo,
+            Status = SubscriptionStatus.Pending,
+            AutoRenew = request.AutoRenew,
+            Notes = "Init subscription"
+        };
+
+        await _tenantRepository.AddTenantAsync(tenant, cancellationToken);
+        await _tenantRepository.AddSubscriptionAsync(subscription, cancellationToken);
+        await _tenantRepository.AddAuditLogAsync(new TenantAuditLog
+        {
+            TenantId = tenant.Id,
+            Action = TenantAuditAction.RegistrationSubmitted,
+            Title = "租户注册",
+            Description = $"提交套餐 {request.TenantPackageId}，时长 {request.DurationMonths} 月"
+        }, cancellationToken);
+
+        await _tenantRepository.SaveChangesAsync(cancellationToken);
+
+        _logger.LogInformation("已注册租户 {TenantCode}", tenant.Code);
+
+        return TenantMapping.ToDto(tenant, subscription, null);
+    }
+}