// 消息路由 + AI 分析
const express = require('express');
const { authMiddleware } = require('../middleware/auth');
const { broadcastToRoomExcludeSelf } = require('../ws');
const { buildSystemPrompt } = require('../ai/prompt');
const { validate, normalize } = require('../ai/validator');
const { callDeepSeek } = require('../ai/client');
const { getHistory, addToHistory, hasPendingAction, handleAIResult, executePendingAction } = require('../handlers');
const db = require('../db');
const { timestamp } = require('../utils');

const router = express.Router();

router.get('/:roomId/messages', authMiddleware, (req, res) => {
  const msgs = db.prepare('SELECT * FROM messages WHERE room_id = ? ORDER BY id ASC').all(req.params.roomId);
  res.json(msgs);
});

router.post('/:roomId/messages', authMiddleware, async (req, res) => {
  const { text, attachments } = req.body;
  console.log('📨 收到消息, text:', (text||'').substring(0,30), 'attachments:', JSON.stringify(attachments));
  const roomId = req.params.roomId;
  const username = req.user.username;
  const now = timestamp();

  const result = db.prepare('INSERT INTO messages (room_id, user, text, attachments, timestamp) VALUES (?,?,?,?,?)').run(
    roomId, username, text || '', attachments ? JSON.stringify(attachments) : null, now
  );
  const msg = { id: result.lastInsertRowid, room_id: roomId, user: username, text: text || '', attachments: attachments || [], timestamp: now };

  const lastMsg = db.prepare('SELECT text, timestamp FROM messages WHERE room_id = ? ORDER BY id DESC LIMIT 1').get(roomId);
  broadcastToRoomExcludeSelf(roomId, username, {
    type: 'new_message', message: msg,
    room_preview: { room_id: roomId, last_message: lastMsg ? lastMsg.text : '', last_time: lastMsg ? lastMsg.timestamp : '' }
  });
  addToHistory(roomId, 'user', `${username}: ${text || '图片'}`);
  res.json(msg);

  if (text && text.trim() === '确认' && hasPendingAction(roomId, username)) {
    executePendingAction(roomId, username);
    return;
  }

  try {
    const history = getHistory(roomId);
    const historyMessages = history.map(e => ({ role: e.role, content: e.content }));
    const aiResponse = await analyzeWithDeepSeek(text || '', historyMessages, username, req.user.isAdmin, roomId);
    if (aiResponse && aiResponse.action !== 'ignore') {
      handleAIResult(aiResponse, roomId, username, text || '', attachments || []);
    }
  } catch (e) { console.error('AI 分析失败:', e); }
});

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} | ${p.created_at}`).join('\n')}`
    : '';
  const systemPrompt = buildSystemPrompt(username, isAdmin) + purchaseContext;
  const messages = [
    { role: 'system', content: systemPrompt },
    ...historyMessages.slice(-30),
    { role: 'user', content: `${username}: ${text}` }
  ];
  const content = await callDeepSeek(messages, 0.1);
  console.log('🤖 AI 返回:', content);
  try {
    const parsed = JSON.parse(content.replace(/```json|```/g, '').trim());
    normalize(parsed);
    const v = validate(parsed);
    if (!v.valid) console.warn('⚠️ AI 返回校验失败:', v.error);
    return parsed;
  } catch (e) {
    // AI 返回非 JSON（如纯文本回复图片消息）→ 降级为 chat
    console.warn('⚠️ AI 返回非 JSON，降级为 chat:', content.substring(0, 50));
    return { action: 'chat', reply: content };
  }
}

module.exports = router;