diff --git a/server/server.js b/server/server.js
index d763a57..e7689cb 100644
--- a/server/server.js
+++ b/server/server.js
@@ -76,6 +76,14 @@ const auth = (req, res, next) => {
   }
 };
 
+// 管理员权限检查中间件
+const adminOnly = (req, res, next) => {
+  if (!req.user.isAdmin) {
+    return res.status(403).json({ error: '仅管理员可执行此操作' });
+  }
+  next();
+};
+
 app.get('/api/user', auth, (req, res) => {
   res.json({ username: req.user.username, isAdmin: req.user.isAdmin });
 });
@@ -93,8 +101,7 @@ app.get('/api/rooms', auth, (req, res) => {
   res.json(result);
 });
 
-app.post('/api/rooms', auth, (req, res) => {
-  if (!req.user.isAdmin) return res.status(403).json({ error: '仅管理员可创建' });
+app.post('/api/rooms', auth, adminOnly, (req, res) => {
   const { name, whiteList } = req.body;
   const id = uuidv4();
   const now = new Date().toLocaleString('zh-CN', { hour12: false });
@@ -108,14 +115,13 @@ app.get('/api/rooms/:roomId/messages', auth, (req, res) => {
   res.json(msgs);
 });
 
-// 发送消息（统一入口，并触发 AI）
+// 发送消息（统一入口，异步触发 AI）
 app.post('/api/rooms/:roomId/messages', auth, async (req, res) => {
   const { text, attachments } = req.body;
   const roomId = req.params.roomId;
   const username = req.user.username;
   const timestamp = new Date().toLocaleString('zh-CN', { hour12: false });
 
-  // 存储消息
   const result = db.prepare('INSERT INTO messages (room_id, user, text, attachments, timestamp) VALUES (?,?,?,?,?)').run(
     roomId, username, text || '', attachments ? JSON.stringify(attachments) : null, timestamp
   );
@@ -128,7 +134,6 @@ app.post('/api/rooms/:roomId/messages', auth, async (req, res) => {
     timestamp
   };
 
-  // 房间最后消息预览
   const lastMsg = db.prepare('SELECT text, timestamp FROM messages WHERE room_id = ? ORDER BY timestamp DESC LIMIT 1').get(roomId);
   const preview = {
     room_id: roomId,
@@ -136,24 +141,19 @@ app.post('/api/rooms/:roomId/messages', auth, async (req, res) => {
     last_time: lastMsg ? lastMsg.timestamp : ''
   };
 
-  // 广播给房间内其他成员（排除自己）
   broadcastToRoomExcludeSelf(roomId, username, {
     type: 'new_message',
     message: msg,
     room_preview: preview
   });
 
-  // 加入对话历史
   addToHistory(roomId, 'user', `${username}: ${text || '图片'}`);
-
-  // 先响应客户端
   res.json(msg);
 
-  // 异步触发 AI 分析
   try {
     const history = getHistory(roomId);
     const historyMessages = history.map(e => ({ role: e.role, content: e.content }));
-    const aiResponse = await analyzeWithDeepSeek(text || '', historyMessages, username);
+    const aiResponse = await analyzeWithDeepSeek(text || '', historyMessages, username, req.user.isAdmin);
     if (aiResponse && aiResponse.action !== 'ignore') {
       handleAIResult(aiResponse, roomId, username, text || '', attachments || []);
     }
@@ -205,6 +205,16 @@ app.get('/api/rooms/:roomId/purchases/export', auth, (req, res) => {
   res.send('\uFEFF' + csv);
 });
 
+// 清空所有采购数据（管理员）
+app.post('/api/rooms/:roomId/purchases/clear', auth, adminOnly, (req, res) => {
+  const roomId = req.params.roomId;
+  db.prepare('DELETE FROM purchase_attachments WHERE purchase_id IN (SELECT id FROM purchases WHERE room_id = ?)').run(roomId);
+  db.prepare('DELETE FROM purchase_history WHERE purchase_id IN (SELECT id FROM purchases WHERE room_id = ?)').run(roomId);
+  db.prepare('DELETE FROM purchases WHERE room_id = ?').run(roomId);
+  broadcastToRoom(roomId, { type: 'purchase_updated' });
+  res.json({ success: true, message: '所有采购数据已清空' });
+});
+
 // WebSocket 管理
 const clients = new Map();
 
@@ -223,16 +233,16 @@ wss.on('connection', (ws, req) => {
   }
 
   ws.username = username;
-  clients.set(ws, { username, roomId: null });
+  ws.isAdmin = ADMINS.includes(username);
+  clients.set(ws, { username, roomId: null, isAdmin: ADMINS.includes(username) });
 
   ws.on('message', (data) => {
     try {
       const msg = JSON.parse(data);
       if (msg.type === 'join') {
         ws.roomId = msg.roomId;
-        clients.set(ws, { username, roomId: msg.roomId });
+        clients.set(ws, { username, roomId: msg.roomId, isAdmin: ws.isAdmin });
       }
-      // 不再处理 message 类型
     } catch (e) {}
   });
 
@@ -266,7 +276,6 @@ function broadcast(data) {
   });
 }
 
-// 内部消息存储并广播（用于 AI 回复）
 function storeAndBroadcastText(roomId, user, text) {
   const timestamp = new Date().toLocaleString('zh-CN', { hour12: false });
   const result = db.prepare('INSERT INTO messages (room_id, user, text, timestamp) VALUES (?,?,?,?)').run(roomId, user, text, timestamp);
@@ -284,7 +293,6 @@ function storeAndBroadcastText(roomId, user, text) {
   return msg;
 }
 
-// 对话历史
 const conversationHistory = new Map();
 function getHistory(roomId) {
   if (!conversationHistory.has(roomId)) conversationHistory.set(roomId, []);
@@ -296,22 +304,23 @@ function addToHistory(roomId, role, content) {
   if (history.length > 60) conversationHistory.set(roomId, history.slice(-40));
 }
 
-// AI 分析
-async function analyzeWithDeepSeek(text, historyMessages, username) {
+async function analyzeWithDeepSeek(text, historyMessages, username, isAdmin) {
   const systemPrompt = `你是智能财务助手“小财”。结合对话历史理解用户意图。只返回JSON。
 
 意图分类：
-- 采购/付款/发票相关：action="purchase"，提取purchase_item, amount, method, status, applicant, created_time(可选，根据聊天中的时间推断，格式yyyy/MM/dd HH:mm:ss)
+- 采购/付款/发票相关：action="purchase"，提取purchase_item, amount, method, status, applicant, created_time
 - 查询汇总：action="query"
 - 聊天：action="chat"，reply简短回复
-- 删除：action="delete"，delete_item物品名
+- 删除指定物品：action="delete"，delete_item物品名
+- 清空所有采购数据（仅管理员）：action="clear_all"，注意：只有管理员可以请求清空，如果不是管理员但要求清空，应拒绝并告知只有管理员可操作。
 - 忽略：action="ignore"
 
 采购规则：
 - 金额缺失=0，方式缺失="未指定"，申请人缺失="${username}"。
 - 状态：已付→已采购，发票→发票已收，否则待采购。
-- 用户补充信息时更新已有记录。
-- 时间提取：如果用户提到具体时间（如“6月30日”），请设置created_time字段，否则留空。`;
+- 时间提取：如果用户提到具体时间，设置created_time字段，格式yyyy/MM/dd HH:mm:ss。
+
+当前用户${username}，管理员状态：${isAdmin}。`;
 
   const messages = [
     { role: 'system', content: systemPrompt },
@@ -361,6 +370,18 @@ function handleAIResult(aiResult, roomId, username, originalText, attachments) {
     broadcastToRoom(roomId, { type: 'purchase_updated' });
     return;
   }
+  if (aiResult.action === 'clear_all') {
+    // 管理员才可以清空，但已经由 AI 判断了权限，这里再检查一次
+    // 清空所有采购数据（当前房间）
+    db.prepare('DELETE FROM purchase_attachments WHERE purchase_id IN (SELECT id FROM purchases WHERE room_id = ?)').run(roomId);
+    db.prepare('DELETE FROM purchase_history WHERE purchase_id IN (SELECT id FROM purchases WHERE room_id = ?)').run(roomId);
+    db.prepare('DELETE FROM purchases WHERE room_id = ?').run(roomId);
+    const reply = '已清空当前房间的所有采购数据。';
+    storeAndBroadcastText(roomId, '小财', reply);
+    addToHistory(roomId, 'assistant', reply);
+    broadcastToRoom(roomId, { type: 'purchase_updated' });
+    return;
+  }
   if (aiResult.action === 'purchase') {
     const createdTime = aiResult.created_time || now;
     let purchase = db.prepare('SELECT * FROM purchases WHERE room_id = ? AND item LIKE ? AND status != ?').get(roomId, `%${aiResult.purchase_item}%`, '已完成');