优化

internal/data/media.go

@@ -55,6 +55,7 @@ func (r *mediaRepo) CreateMedia(ctx context.Context, v *biz.MediaFile) error {
 	}
 	v.ID = po.ID
 	v.CreatedAt = po.CreatedAt
+	v.UpdatedAt = po.UpdatedAt
 	return nil
 }
 func (r *mediaRepo) FindMedia(ctx context.Context, id uint) (*biz.MediaFile, error) {
@@ -119,7 +120,13 @@ func (r *mediaRepo) ListMedia(ctx context.Context, filter biz.MediaFilter) ([]*b
 	return out, total, nil
 }
 func (r *mediaRepo) UpdateMediaName(ctx context.Context, id uint, name string) error {
-	return r.data.gormDB.WithContext(ctx).Model(&mediaPO{}).Where("id = ?", id).Update("name", name).Error
+	// The compatible flow performs a First before Update, so a missing record returns a
+	// not-found error instead of silently succeeding with RowsAffected=0.
+	var po mediaPO
+	if err := r.data.gormDB.WithContext(ctx).Where("id = ?", id).First(&po).Error; err != nil {
+		return err
+	}
+	return r.data.gormDB.WithContext(ctx).Model(&po).Update("name", name).Error
 }
 func (r *mediaRepo) DeleteMedia(ctx context.Context, id uint) error {
 	return r.data.gormDB.WithContext(ctx).Unscoped().Delete(&mediaPO{}, id).Error
@@ -176,14 +183,17 @@ func (r *mediaRepo) ListCategories(ctx context.Context) ([]*biz.AttachmentCatego
 	}
 	byID := map[uint]*biz.AttachmentCategory{}
 	for _, po := range pos {
-		byID[po.ID] = &biz.AttachmentCategory{ID: po.ID, CreatedAt: po.CreatedAt, UpdatedAt: po.UpdatedAt, Name: po.Name, ParentID: po.ParentID, Children: []*biz.AttachmentCategory{}}
+		// Children remains nil for leaf nodes, which serializes as null.
+		byID[po.ID] = &biz.AttachmentCategory{ID: po.ID, CreatedAt: po.CreatedAt, UpdatedAt: po.UpdatedAt, Name: po.Name, ParentID: po.ParentID}
 	}
 	roots := []*biz.AttachmentCategory{}
 	for _, po := range pos {
 		v := byID[po.ID]
 		if parent := byID[po.ParentID]; parent != nil {
 			parent.Children = append(parent.Children, v)
-		} else {
+		} else if po.ParentID == 0 {
+			// The tree starts at parent id 0; non-zero orphan nodes are
+			// intentionally omitted instead of being promoted to roots.
 			roots = append(roots, v)
 		}
 	}