细节优化

backend/app/api/categories.py

@@ -52,10 +52,13 @@ def get_category_tree(
     """获取完整目录树（含文档数量）。"""
     _check_kb_owner(kb_id, user, db)
 
-    # 获取所有分类
+    # 获取所有未删除的分类
     stmt = (
         select(DocumentCategory)
-        .where(DocumentCategory.knowledge_base_id == kb_id)
+        .where(
+            DocumentCategory.knowledge_base_id == kb_id,
+            DocumentCategory.deleted_at.is_(None),
+        )
         .order_by(DocumentCategory.sort_order, DocumentCategory.name)
     )
     all_cats = list(db.scalars(stmt).all())
@@ -110,7 +113,10 @@ def list_categories_flat(
 
     stmt = (
         select(DocumentCategory)
-        .where(DocumentCategory.knowledge_base_id == kb_id)
+        .where(
+            DocumentCategory.knowledge_base_id == kb_id,
+            DocumentCategory.deleted_at.is_(None),
+        )
         .order_by(DocumentCategory.path, DocumentCategory.sort_order)
     )
     cats = list(db.scalars(stmt).all())
@@ -236,32 +242,44 @@ def delete_category(
     user: User = Depends(get_current_user),
     db: Session = Depends(get_db),
 ) -> None:
-    """删除分类（同时删除子分类，关联文档的 category_id 置 NULL）。"""
+    """删除分类 → 进回收站（含全部子分类及其下文档，3 天后自动彻底删除）。"""
+    from datetime import datetime
+
+    from app.models.document import Document
+
     _check_kb_owner(kb_id, user, db)
     cat = db.get(DocumentCategory, cat_id)
-    if cat is None or cat.knowledge_base_id != kb_id:
+    if cat is None or cat.knowledge_base_id != kb_id or cat.deleted_at:
         raise NotFoundError("分类不存在。")
 
-    # 删除所有子分类
+    now = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+
+    # 收集本分类 + 所有存活的后代分类
+    target_ids = [cat_id]
     if cat.path:
         stmt = select(DocumentCategory).where(
             DocumentCategory.knowledge_base_id == kb_id,
             DocumentCategory.path.startswith(cat.path),
-            DocumentCategory.id != cat_id,
+            DocumentCategory.deleted_at.is_(None),
         )
-        children = list(db.scalars(stmt).all())
-        for child in children:
-            db.delete(child)
+        for c in db.scalars(stmt).all():
+            if c.id != cat_id:
+                target_ids.append(c.id)
 
-    # 关联文档的 category_id 置 NULL
-    from app.models.document import Document
+    # 软删除分类树
+    for cid in target_ids:
+        c = db.get(DocumentCategory, cid)
+        c.deleted_at = now
 
-    doc_stmt = select(Document).where(Document.category_id == cat_id)
-    docs = list(db.scalars(doc_stmt).all())
-    for doc in docs:
-        doc.category_id = None
+    # 软删除目录下的文档（同一批次时间戳，便于整组恢复）
+    doc_stmt = select(Document).where(
+        Document.category_id.in_(target_ids),
+        Document.status != "DELETED",
+    )
+    for doc in db.scalars(doc_stmt).all():
+        doc.status = "DELETED"
+        doc.deleted_at = now
 
-    db.delete(cat)
     db.commit()