fix: Markdown开关改用data属性存储内容，修复切换失效问题

- 数据列表中未读数据（views=0）显示特殊样式（黄色背景+红色边框+红点标记）
- 左侧类别显示未读数量（红色badge）
- API返回unread和unread_by_type统计数据

xian_favor/db.py

@@ -131,6 +131,19 @@ class Database:
                 )
             """)
             
+            # 文件夹表
+            cursor.execute("""
+                CREATE TABLE IF NOT EXISTS folders (
+                    id INTEGER PRIMARY KEY AUTOINCREMENT,
+                    name TEXT NOT NULL,
+                    type TEXT NOT NULL,
+                    parent_id INTEGER DEFAULT NULL,
+                    created_at TEXT NOT NULL,
+                    updated_at TEXT NOT NULL,
+                    FOREIGN KEY (parent_id) REFERENCES folders(id) ON DELETE CASCADE
+                )
+            """)
+            
             # 创建索引
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_items_type ON items(type)")
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_items_status ON items(status)")
@@ -163,6 +176,42 @@ class Database:
             except sqlite3.OperationalError:
                 cursor.execute("ALTER TABLE items ADD COLUMN deleted_at TEXT")
             
+            # 检查并添加 folder_id 字段（兼容旧数据库）
+            try:
+                cursor.execute("SELECT folder_id FROM items LIMIT 1")
+            except sqlite3.OperationalError:
+                cursor.execute("ALTER TABLE items ADD COLUMN folder_id INTEGER DEFAULT NULL")
+            
+            # 创建 folder 相关索引
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_items_folder ON items(folder_id)")
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_folders_type ON folders(type)")
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_folders_parent ON folders(parent_id)")
+            
+            # 检查并添加 is_pinned 字段（置顶功能，兼容旧数据库）
+            try:
+                cursor.execute("SELECT is_pinned FROM items LIMIT 1")
+            except sqlite3.OperationalError:
+                cursor.execute("ALTER TABLE items ADD COLUMN is_pinned INTEGER DEFAULT 0")
+            
+            # 创建 is_pinned 索引
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_items_pinned ON items(is_pinned)")
+            
+            # 待办事务表（关联到文本类别的items）
+            cursor.execute("""
+                CREATE TABLE IF NOT EXISTS todo_events (
+                    id INTEGER PRIMARY KEY AUTOINCREMENT,
+                    item_id INTEGER NOT NULL,
+                    content TEXT NOT NULL,
+                    remaining_days INTEGER DEFAULT 1,
+                    is_completed INTEGER DEFAULT 0,
+                    created_at TEXT NOT NULL,
+                    updated_at TEXT NOT NULL,
+                    FOREIGN KEY (item_id) REFERENCES items(id) ON DELETE CASCADE
+                )
+            """)
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_todo_events_item ON todo_events(item_id)")
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_todo_events_created ON todo_events(created_at)")
+            
             conn.commit()
     
     # ============ Item 操作 ============
@@ -170,7 +219,8 @@ class Database:
     def create_item(self, type: str = "text", title: str = None, content: str = None,
                     url: str = None, source: str = None, status: str = "pending",
                     priority: str = "medium", due_date: str = None, note: str = None,
-                    tags: List[str] = None, is_starred: bool = False) -> int:
+                    tags: List[str] = None, is_starred: bool = False, 
+                    folder_id: int = None) -> int:
         """创建新条目"""
         self._ensure_init()
         now = datetime.now().isoformat()
@@ -184,9 +234,9 @@ class Database:
         with self.get_conn() as conn:
             cursor = conn.cursor()
             cursor.execute("""
-                INSERT INTO items (type, title, content, url, source, status, priority, due_date, note, is_starred, created_at, updated_at)
-                VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
-            """, (type, title, content, url, source, status, priority, due_date, note, 1 if is_starred else 0, now, now))
+                INSERT INTO items (type, title, content, url, source, status, priority, due_date, note, is_starred, folder_id, created_at, updated_at)
+                VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+            """, (type, title, content, url, source, status, priority, due_date, note, 1 if is_starred else 0, folder_id, now, now))
             item_id = cursor.lastrowid
             
             # 添加标签
@@ -210,12 +260,14 @@ class Database:
             return item
     
     def list_items(self, type: str = None, status: str = None, tag: str = None,
-                   keyword: str = None, starred: bool = None, sort_by: str = None,
-                   sort_order: str = None, limit: int = 50, offset: int = 0) -> List[Dict[str, Any]]:
+                   keyword: str = None, starred: bool = None, folder_id: int = None,
+                   sort_by: str = None, sort_order: str = None, 
+                   limit: int = 50, offset: int = 0) -> List[Dict[str, Any]]:
         """列出条目
         
         sort_by: created_at, updated_at
         sort_order: desc, asc
+        folder_id: 文件夹ID，None表示不限制，-1表示未分类（folder_id为null）
         """
         with self.get_conn() as conn:
             cursor = conn.cursor()
@@ -245,6 +297,15 @@ class Database:
                 conditions.append("i.is_starred = ?")
                 params.append(1 if starred else 0)
             
+            # 文件夹过滤
+            if folder_id is not None:
+                if folder_id == -1:
+                    # -1 表示未分类（folder_id 为 null）
+                    conditions.append("i.folder_id IS NULL")
+                else:
+                    conditions.append("i.folder_id = ?")
+                    params.append(folder_id)
+            
             if keyword:
                 conditions.append("(i.title LIKE ? OR i.content LIKE ? OR i.note LIKE ?)")
                 keyword_pattern = f"%{keyword}%"
@@ -253,18 +314,16 @@ class Database:
             if conditions:
                 query += " WHERE " + " AND ".join(conditions)
             
-            # 排序逻辑
+            # 排序逻辑：置顶 > 关注 > 创建时间
             if sort_by == 'updated_at':
                 order_field = 'i.updated_at'
             elif sort_by == 'created_at':
                 order_field = 'i.created_at'
             else:
-                # 默认：重点关注优先 + 创建时间降序
+                # 默认：置顶优先 + 关注优先 + 创建时间降序
                 order_field = 'i.created_at'
             
-            order_dir = 'DESC' if (sort_order == 'asc' or sort_order is None) else 'ASC'
-            # 这里反转逻辑：用户选择"降序"时用DESC，选择"升序"时用ASC
-            
+            # 确定排序方向
             if sort_order == 'asc':
                 order_dir = 'ASC'
             elif sort_order == 'desc':
@@ -272,12 +331,12 @@ class Database:
             else:
                 order_dir = 'DESC'  # 默认降序
             
-            # 如果有指定排序字段，按该字段排序；否则默认重点关注优先
+            # 如果有指定排序字段，按该字段排序，但置顶始终优先
             if sort_by:
-                query += f" ORDER BY {order_field} {order_dir} LIMIT ? OFFSET ?"
+                query += f" ORDER BY i.is_pinned DESC, {order_field} {order_dir} LIMIT ? OFFSET ?"
             else:
-                # 默认：重点关注优先，然后创建时间降序
-                query += f" ORDER BY i.is_starred DESC, i.created_at DESC LIMIT ? OFFSET ?"
+                # 默认：置顶 > 关注 > 创建时间降序
+                query += f" ORDER BY i.is_pinned DESC, i.is_starred DESC, i.created_at DESC LIMIT ? OFFSET ?"
             params.extend([limit, offset])
             
             cursor.execute(query, params)
@@ -290,7 +349,7 @@ class Database:
             return items
     
     def count_items(self, type: str = None, status: str = None, tag: str = None,
-                    keyword: str = None, starred: bool = None) -> int:
+                    keyword: str = None, starred: bool = None, folder_id: int = None) -> int:
         """计算符合条件的条目总数"""
         with self.get_conn() as conn:
             cursor = conn.cursor()
@@ -322,6 +381,15 @@ class Database:
                 keyword_pattern = f"%{keyword}%"
                 params.extend([keyword_pattern, keyword_pattern, keyword_pattern])
             
+            # 文件夹过滤
+            if folder_id is not None:
+                if folder_id == -1:
+                    # 未分类：folder_id为NULL
+                    conditions.append("i.folder_id IS NULL")
+                else:
+                    conditions.append("i.folder_id = ?")
+                    params.append(folder_id)
+            
             if conditions:
                 query += " WHERE " + " AND ".join(conditions)
             
@@ -330,7 +398,7 @@ class Database:
     
     def update_item(self, item_id: int, **kwargs) -> bool:
         """更新条目"""
-        allowed_fields = ['type', 'title', 'content', 'url', 'source', 'status', 'priority', 'due_date', 'note', 'is_starred']
+        allowed_fields = ['type', 'title', 'content', 'url', 'source', 'status', 'priority', 'due_date', 'note', 'is_starred', 'folder_id']
         update_fields = {k: v for k, v in kwargs.items() if k in allowed_fields}
         
         # 只有 tags 变化也算有效更新
@@ -456,6 +524,31 @@ class Database:
             conn.commit()
             return cursor.rowcount > 0
     
+    def toggle_pin(self, item_id: int) -> bool:
+        """切换置顶状态"""
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            # 先获取当前状态
+            cursor.execute("SELECT is_pinned FROM items WHERE id = ?", (item_id,))
+            row = cursor.fetchone()
+            if not row:
+                return False
+            
+            new_status = 0 if row['is_pinned'] else 1
+            now = datetime.now().isoformat()
+            cursor.execute("UPDATE items SET is_pinned = ?, updated_at = ? WHERE id = ?", (new_status, now, item_id))
+            conn.commit()
+            return True
+    
+    def set_pin(self, item_id: int, pinned: bool = True) -> bool:
+        """设置置顶状态"""
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            now = datetime.now().isoformat()
+            cursor.execute("UPDATE items SET is_pinned = ?, updated_at = ? WHERE id = ?", (1 if pinned else 0, now, item_id))
+            conn.commit()
+            return cursor.rowcount > 0
+    
     def increment_views(self, item_id: int) -> bool:
         """增加阅读数"""
         with self.get_conn() as conn:
@@ -464,6 +557,116 @@ class Database:
             conn.commit()
             return cursor.rowcount > 0
     
+    def move_item_to_folder(self, item_id: int, folder_id: int) -> bool:
+        """将条目移动到文件夹"""
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            now = datetime.now().isoformat()
+            cursor.execute("UPDATE items SET folder_id = ?, updated_at = ? WHERE id = ?", (folder_id, now, item_id))
+            conn.commit()
+            return cursor.rowcount > 0
+    
+    # ============ Folder 文件夹操作 ============
+    
+    def create_folder(self, name: str, type: str, parent_id: int = None) -> int:
+        """创建文件夹
+        
+        Args:
+            name: 文件夹名称
+            type: 类别类型（text/link/column/todo）
+            parent_id: 父文件夹ID（目前不支持嵌套，预留）
+        """
+        self._ensure_init()
+        now = datetime.now().isoformat()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("""
+                INSERT INTO folders (name, type, parent_id, created_at, updated_at)
+                VALUES (?, ?, ?, ?, ?)
+            """, (name, type, parent_id, now, now))
+            folder_id = cursor.lastrowid
+            conn.commit()
+            return folder_id
+    
+    def get_folder(self, folder_id: int) -> Optional[Dict[str, Any]]:
+        """获取文件夹信息"""
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("SELECT * FROM folders WHERE id = ?", (folder_id,))
+            row = cursor.fetchone()
+            if not row:
+                return None
+            folder = dict(row)
+            # 获取文件夹内条目数量
+            cursor.execute("SELECT COUNT(*) FROM items WHERE folder_id = ? AND is_deleted = 0", (folder_id,))
+            folder['item_count'] = cursor.fetchone()[0]
+            return folder
+    
+    def list_folders(self, type: str = None) -> List[Dict[str, Any]]:
+        """列出文件夹
+        
+        Args:
+            type: 按类型过滤，None表示列出所有
+        """
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            if type:
+                cursor.execute("SELECT * FROM folders WHERE type = ? ORDER BY created_at DESC", (type,))
+            else:
+                cursor.execute("SELECT * FROM folders ORDER BY created_at DESC")
+            
+            folders = []
+            for row in cursor.fetchall():
+                folder = dict(row)
+                # 获取文件夹内条目数量
+                cursor.execute("SELECT COUNT(*) FROM items WHERE folder_id = ? AND is_deleted = 0", (folder['id'],))
+                folder['item_count'] = cursor.fetchone()[0]
+                folders.append(folder)
+            
+            return folders
+    
+    def update_folder(self, folder_id: int, name: str = None) -> bool:
+        """更新文件夹"""
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            now = datetime.now().isoformat()
+            
+            if name:
+                cursor.execute("UPDATE folders SET name = ?, updated_at = ? WHERE id = ?", (name, now, folder_id))
+                conn.commit()
+                return cursor.rowcount > 0
+            return False
+    
+    def delete_folder(self, folder_id: int, move_items_to_root: bool = True) -> bool:
+        """删除文件夹
+        
+        Args:
+            folder_id: 文件夹ID
+            move_items_to_root: 是否将条目移出文件夹（到未分类），True则移动，False则一起删除
+        """
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            
+            if move_items_to_root:
+                # 将条目移出文件夹（folder_id设为null）
+                cursor.execute("UPDATE items SET folder_id = NULL WHERE folder_id = ?", (folder_id,))
+            else:
+                # 删除文件夹内的所有条目
+                cursor.execute("DELETE FROM items WHERE folder_id = ?", (folder_id,))
+            
+            # 删除文件夹
+            cursor.execute("DELETE FROM folders WHERE id = ?", (folder_id,))
+            conn.commit()
+            return cursor.rowcount > 0
+    
+    def count_items_by_folder(self, folder_id: int) -> int:
+        """统计文件夹内的条目数量"""
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("SELECT COUNT(*) FROM items WHERE folder_id = ? AND is_deleted = 0", (folder_id,))
+            return cursor.fetchone()[0]
+    
     # ============ Draft 草稿操作 ============
     
     def save_draft(self, type: str = "text", title: str = None, content: str = None,
@@ -748,15 +951,23 @@ class Database:
             stats = {}
             
             # 总数
-            cursor.execute("SELECT COUNT(*) as count FROM items")
+            cursor.execute("SELECT COUNT(*) as count FROM items WHERE is_deleted = 0")
             stats['total'] = cursor.fetchone()['count']
             
             # 按类型统计
-            cursor.execute("SELECT type, COUNT(*) as count FROM items GROUP BY type")
+            cursor.execute("SELECT type, COUNT(*) as count FROM items WHERE is_deleted = 0 GROUP BY type")
             stats['by_type'] = {row['type']: row['count'] for row in cursor.fetchall()}
             
+            # 未读数量统计（views = 0）
+            cursor.execute("SELECT COUNT(*) as count FROM items WHERE is_deleted = 0 AND (views IS NULL OR views = 0)")
+            stats['unread'] = cursor.fetchone()['count']
+            
+            # 按类型统计未读数量
+            cursor.execute("SELECT type, COUNT(*) as count FROM items WHERE is_deleted = 0 AND (views IS NULL OR views = 0) GROUP BY type")
+            stats['unread_by_type'] = {row['type']: row['count'] for row in cursor.fetchall()}
+            
             # 待办状态统计
-            cursor.execute("SELECT status, COUNT(*) as count FROM items WHERE type = 'todo' GROUP BY status")
+            cursor.execute("SELECT status, COUNT(*) as count FROM items WHERE type = 'todo' AND is_deleted = 0 GROUP BY status")
             stats['todo_status'] = {row['status']: row['count'] for row in cursor.fetchall()}
             
             # 标签数
@@ -1011,6 +1222,93 @@ class Database:
                 # 删除
                 self.delete_backup(backup['name'])
 
+    # ============ Todo Events 待办事务操作 ============
+    
+    def create_todo_event(self, item_id: int, content: str, remaining_days: int = 1) -> int:
+        """创建待办事务"""
+        self._ensure_init()
+        now = datetime.now().isoformat()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("""
+                INSERT INTO todo_events (item_id, content, remaining_days, is_completed, created_at, updated_at)
+                VALUES (?, ?, ?, 0, ?, ?)
+            """, (item_id, content, remaining_days, now, now))
+            conn.commit()
+            return cursor.lastrowid
+    
+    def list_todo_events(self, item_id: int, limit: int = 10, offset: int = 0) -> List[Dict[str, Any]]:
+        """列出待办事务（按时间倒序）"""
+        self._ensure_init()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("""
+                SELECT * FROM todo_events 
+                WHERE item_id = ? 
+                ORDER BY created_at DESC 
+                LIMIT ? OFFSET ?
+            """, (item_id, limit, offset))
+            rows = cursor.fetchall()
+            return [dict(row) for row in rows]
+    
+    def count_todo_events(self, item_id: int) -> int:
+        """计算待办事务总数"""
+        self._ensure_init()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("SELECT COUNT(*) as count FROM todo_events WHERE item_id = ?", (item_id,))
+            return cursor.fetchone()['count']
+    
+    def get_todo_event(self, event_id: int) -> Optional[Dict[str, Any]]:
+        """获取单个待办事务"""
+        self._ensure_init()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("SELECT * FROM todo_events WHERE id = ?", (event_id,))
+            row = cursor.fetchone()
+            return dict(row) if row else None
+    
+    def update_todo_event(self, event_id: int, content: str = None, remaining_days: int = None, is_completed: bool = None) -> bool:
+        """更新待办事务"""
+        self._ensure_init()
+        now = datetime.now().isoformat()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            
+            # 获取当前数据
+            cursor.execute("SELECT * FROM todo_events WHERE id = ?", (event_id,))
+            row = cursor.fetchone()
+            if not row:
+                return False
+            
+            # 更新字段
+            new_content = content if content is not None else row['content']
+            new_days = remaining_days if remaining_days is not None else row['remaining_days']
+            new_completed = 1 if is_completed is True else (0 if is_completed is False else row['is_completed'])
+            
+            cursor.execute("""
+                UPDATE todo_events 
+                SET content = ?, remaining_days = ?, is_completed = ?, updated_at = ?
+                WHERE id = ?
+            """, (new_content, new_days, new_completed, now, event_id))
+            conn.commit()
+            return True
+    
+    def delete_todo_event(self, event_id: int) -> bool:
+        """删除待办事务"""
+        self._ensure_init()
+        
+        with self.get_conn() as conn:
+            cursor = conn.cursor()
+            cursor.execute("DELETE FROM todo_events WHERE id = ?", (event_id,))
+            conn.commit()
+            return cursor.rowcount > 0
+
 
 # 全局数据库实例
 db = Database()