server.js

require('dotenv').config();
const express = require('express');
const cors = require('cors');
const path = require('path');
// 使用RAG增强的agent
const { processUserQuery } = require('./rag-agent');

const app = express();
app.use(cors());
app.use(express.json());

// 提供静态文件服务
app.use(express.static(path.join(__dirname)));

// 根路径重定向到新版界面
app.get('/', (req, res) => {
  res.sendFile(path.join(__dirname, 'index-v2.html'));
});

// 保留旧版界面的访问
app.get('/v1', (req, res) => {
  res.sendFile(path.join(__dirname, 'index.html'));
});

// 健康检查
app.get('/api/health', (req, res) => {
  res.json({ 
    status: 'ok',
    timestamp: new Date().toISOString(),
    version: '1.0.0'
  });
});

// 产品推荐API
app.post('/api/recommend', async (req, res) => {
  try {
    const { query } = req.body;
    if (!query) {
      return res.status(400).json({ 
        success: false,
        error: 'Query is required',
        code: 'MISSING_QUERY'
      });
    }
    
    const result = await processUserQuery(query);
    res.json({
      success: true,
      data: result,
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('Recommendation error:', error);
    res.status(500).json({ 
      success: false,
      error: 'Internal server error',
      code: 'PROCESSING_ERROR'
    });
  }
});

// 产品对比API
app.post('/api/compare', async (req, res) => {
  try {
    const { products } = req.body;
    if (!products || !Array.isArray(products) || products.length < 2) {
      return res.status(400).json({ 
        success: false,
        error: 'At least 2 products required',
        code: 'INSUFFICIENT_PRODUCTS'
      });
    }
    
    const result = await processUserQuery(`Compare ${products.join(' and ')}`);
    res.json({
      success: true,
      data: result,
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('Comparison error:', error);
    res.status(500).json({ 
      success: false,
      error: 'Internal server error',
      code: 'PROCESSING_ERROR'
    });
  }
});

// 规格查询API
app.post('/api/spec', async (req, res) => {
  try {
    const { model, spec } = req.body;
    if (!model) {
      return res.status(400).json({ 
        success: false,
        error: 'Product model is required',
        code: 'MISSING_MODEL'
      });
    }
    
    const result = await processUserQuery(`What are the ${spec || 'specifications'} of ${model}?`);
    res.json({
      success: true,
      data: result,
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('Spec query error:', error);
    res.status(500).json({ 
      success: false,
      error: 'Internal server error',
      code: 'PROCESSING_ERROR'
    });
  }
});

// 功能查询API
app.post('/api/features', async (req, res) => {
  try {
    const { model, feature } = req.body;
    if (!model) {
      return res.status(400).json({ 
        success: false,
        error: 'Product model is required',
        code: 'MISSING_MODEL'
      });
    }
    
    const result = await processUserQuery(`What ${feature || 'features'} does ${model} have?`);
    res.json({
      success: true,
      data: result,
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('Feature query error:', error);
    res.status(500).json({ 
      success: false,
      error: 'Internal server error',
      code: 'PROCESSING_ERROR'
    });
  }
});

// 通用查询API
app.post('/api/query', async (req, res) => {
  try {
    const { message } = req.body;
    if (!message) {
      return res.status(400).json({ 
        success: false,
        error: 'Message is required',
        code: 'MISSING_MESSAGE'
      });
    }
    
    const result = await processUserQuery(message);
    res.json({
      success: true,
      data: result,
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('Query error:', error);
    res.status(500).json({ 
      success: false,
      error: 'Internal server error',
      code: 'PROCESSING_ERROR'
    });
  }
});

// 全局错误处理中间件
app.use((err, req, res, next) => {
  console.error('Unhandled error:', err);
  res.status(500).json({ 
    error: 'Internal server error',
    message: process.env.NODE_ENV === 'development' ? err.message : 'Something went wrong'
  });
});

// 404处理
app.use((req, res) => {
  res.status(404).json({ error: 'API endpoint not found' });
});

const PORT = process.env.PORT || 3001;
app.listen(PORT, () => {
  console.log(`🚀 TP-Link Product Assistant Server running on port ${PORT}`);
  console.log(`📱 Web interface: http://localhost:${PORT}`);
  console.log(`🔧 API base URL: http://localhost:${PORT}/api`);
  console.log(`Environment: ${process.env.NODE_ENV || 'development'}`);
});