优化缓存命中

server/routes/messages.js

@@ -61,21 +61,32 @@ router.post('/:roomId/messages', authMiddleware, async (req, res) => {
 });
 
 async function analyzeWithDeepSeek(text, historyMessages, username, isAdmin, roomId) {
-  // 注入当前房间采购清单上下文
-  const purchases = db.prepare("SELECT item, quantity, amount, status, created_at FROM purchases WHERE room_id = ? ORDER BY created_at DESC LIMIT 10").all(roomId);
-  const purchaseContext = purchases.length
-    ? `\n📋 当前房间采购清单（最近10条）：\n${purchases.map(p => `- ${p.item} | ×${p.quantity} | ¥${p.amount} | ${p.status} | ${p.created_at}`).join('\n')}`
+  // 采购清单（单独消息）
+  var purchases = db.prepare("SELECT item, quantity, amount, status, created_at FROM purchases WHERE room_id = ? ORDER BY created_at DESC LIMIT 10").all(roomId);
+  var purchaseMsg = purchases.length
+    ? '📋 当前房间采购清单（最近10条）：\n' + purchases.map(function(p) { return '- ' + p.item + ' | ×' + p.quantity + ' | ¥' + p.amount + ' | ' + p.status + ' | ' + p.created_at; }).join('\n')
     : '';
-  const systemPrompt = buildSystemPrompt(username, isAdmin) + purchaseContext;
-  const messages = [
-    { role: 'system', content: systemPrompt },
-    ...historyMessages.slice(-30),
-    { role: 'user', content: `${username}: ${text}` }
+  // 系统提示词（稳定，不含时间）
+  var systemPrompt = buildSystemPrompt(username, isAdmin);
+  var messages = [
+    { role: 'system', content: systemPrompt }
   ];
+  // 全量历史，每 30 条一轮前缀稳定期，轮内全部命中
+  historyMessages.forEach(function(m) { messages.push(m); });
+  // 采购清单、时间放最后，变动不影响历史命中
+  if (purchaseMsg) messages.push({ role: 'system', content: purchaseMsg });
+  messages.push({ role: 'system', content: '当前服务器时间：' + new Date().toLocaleString('zh-CN', { timeZone: 'Asia/Shanghai', hour12: false }) });
+  // 当前消息已在 historyMessages 中，不再重复 push
   const content = await callDeepSeek(messages, username);
-  console.log('🤖 AI 返回:', content);
+  console.log('🤖 AI 返回:', content.substring(0, 200));
+  // 打印消息结构，方便排查缓存
+  console.log('📋 消息结构:', messages.map(function(m, i) {
+    var preview = m.content.substring(0, 60).split('\n').join(' ');
+    return '[' + i + '] ' + m.role + ' (' + m.content.length + '字): ' + preview;
+  }).join('\n'));
   try {
     var cleaned = content.replace(/```json|```/g, '').trim();
+    if (!cleaned) { console.warn('⚠️ AI 返回空内容'); return { action: 'ignore' }; }
     var parsed = JSON.parse(cleaned);
     // 支持批量：AI 可能返回数组
     if (Array.isArray(parsed)) {