接入分销订单支付退款与站点隔离

backend/internal/modules/distribution/repository.go

@@ -21,12 +21,38 @@ var (
 	ErrInvalidPeriod           = errors.New("invalid distribution settlement period")
 	ErrSettlementBatchNotFound = errors.New("distribution settlement batch not found")
 	ErrBatchAlreadySettled     = errors.New("distribution settlement batch already settled")
+	ErrSiteAccessDenied        = errors.New("distribution site access denied")
 )
 
 type Repository struct{ db *gorm.DB }
 
 func NewRepository(db *gorm.DB) *Repository { return &Repository{db: db} }
 
+func (r *Repository) ScopeSiteID(ctx context.Context, adminID, requested uint64) (uint64, error) {
+	if adminID == 0 {
+		return requested, nil
+	}
+	var members []model.DistributionSiteMember
+	if err := r.db.WithContext(ctx).Where("admin_user_id = ? AND status = 'active'", adminID).Find(&members).Error; err != nil {
+		return 0, err
+	}
+	if len(members) == 0 {
+		return requested, nil
+	}
+	if requested > 0 {
+		for _, member := range members {
+			if member.SiteID == requested {
+				return requested, nil
+			}
+		}
+		return 0, ErrSiteAccessDenied
+	}
+	if len(members) == 1 {
+		return members[0].SiteID, nil
+	}
+	return 0, nil
+}
+
 func (r *Repository) ListSites(ctx context.Context) ([]SiteDTO, error) {
 	var rows []model.DistributionSite
 	if err := r.db.WithContext(ctx).Order("id ASC").Find(&rows).Error; err != nil {