const http = require('http');
const fs = require('fs');
const path = require('path');
const mysql = require('mysql2/promise');
const OssUploader = require('./oss-uploader');

const port = 3008;

// 数据库配置
const dbConfig = {
  host: process.env.DB_HOST || '1.95.162.61',
  user: process.env.DB_USER || 'root',
  password: process.env.DB_PASSWORD || 'schl@2025',
  database: process.env.DB_NAME || 'wechat_app',
  waitForConnections: true,
  connectionLimit: 20,
  queueLimit: 0,
  connectTimeout: 10000,
  timezone: '+08:00'
};

// 创建数据库连接池
const pool = mysql.createPool(dbConfig);

// 测试数据库连接
async function testDbConnection() {
  try {
    const connection = await pool.getConnection();
    console.log('数据库连接成功');
    connection.release();
  } catch (error) {
    console.error('数据库连接失败:', error.message);
  }
}

testDbConnection();

const server = http.createServer(async (req, res) => {
  // 健康检查端点
  if (req.method === 'GET' && req.url === '/health') {
    try {
      // 测试数据库连接
      const [rows] = await pool.execute('SELECT 1');
      
      // 测试OSS连接
      const ossStatus = await OssUploader.testConnection();
      
      res.writeHead(200, { 
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
        'Access-Control-Allow-Headers': 'Content-Type'
      });
      res.end(JSON.stringify({ 
        success: true, 
        status: 'healthy',
        database: 'connected',
        oss: ossStatus.success ? 'connected' : 'disconnected',
        timestamp: new Date().toISOString()
      }));
    } catch (error) {
      console.error('健康检查失败:', error.message);
      res.writeHead(503, { 
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
        'Access-Control-Allow-Headers': 'Content-Type'
      });
      res.end(JSON.stringify({ 
        success: false, 
        status: 'unhealthy',
        error: error.message,
        timestamp: new Date().toISOString()
      }));
    }
    return;
  }

  // 处理GET请求，获取最新的合格证信息
  if (req.method === 'GET' && req.url.startsWith('/getLatestCertificate')) {
    try {
      // 解析URL参数，获取sessionId
      const urlParams = new URLSearchParams(req.url.split('?')[1] || '');
      const sessionId = urlParams.get('sessionId');
      
      console.log('获取合格证信息，sessionId:', sessionId);
      
      // 从数据库获取对应会话的最新合格证信息
      let query, params;
      if (sessionId) {
        query = 'SELECT company as subjectName, phoneNumber as contact, productName, grossWeight as weight, commitBasis as basis, origin, DATE_FORMAT(issueDate, "%Y-%m-%d") as date, signature, qrCodeUrl FROM certificate WHERE sessionId = ? ORDER BY id DESC LIMIT 1';
        params = [sessionId];
      } else {
        query = 'SELECT company as subjectName, phoneNumber as contact, productName, grossWeight as weight, commitBasis as basis, origin, DATE_FORMAT(issueDate, "%Y-%m-%d") as date, signature, qrCodeUrl FROM certificate WHERE sessionId IS NULL ORDER BY id DESC LIMIT 1';
        params = [];
      }
      
      const [rows] = await pool.execute(query, params);
      
      const certificate = rows.length > 0 ? rows[0] : null;
      console.log('从数据库获取的最新合格证信息:', certificate);
      
      // 返回成功响应
      res.writeHead(200, { 
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
        'Access-Control-Allow-Headers': 'Content-Type'
      });
      res.end(JSON.stringify({ success: true, certificate }));
    } catch (error) {
      console.error('获取合格证信息失败:', error.message);
      res.writeHead(500, { 
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
        'Access-Control-Allow-Headers': 'Content-Type'
      });
      res.end(JSON.stringify({ success: false, error: '获取失败，请重试' }));
    }
    return;
  }

  // 处理POST请求
  if (req.method === 'POST' && req.url === '/submit') {
    try {
      let body = '';
      req.on('data', chunk => {
        body += chunk.toString();
      });
      
      req.on('end', async () => {
        try {
          // 解析表单数据
          const formData = new URLSearchParams(body);
          // 使用当前时间作为开具日期，数据库连接已配置为北京时间
          const now = new Date();
          
          const sessionId = formData.get('sessionId');
          
          const certificate = {
            subjectName: formData.get('subjectName'),
            contact: formData.get('contact'),
            productName: formData.get('productName'),
            weight: formData.get('weight'),
            basis: formData.get('basis'),
            origin: formData.get('origin'),
            date: now,
            signature: formData.get('signature'),
            sessionId: sessionId
          };
          
          console.log('接收到的表单数据:', {
            subjectName: certificate.subjectName,
            contact: certificate.contact,
            productName: certificate.productName,
            weight: certificate.weight,
            basis: certificate.basis,
            origin: certificate.origin,
            date: certificate.date.toISOString(),
            hasSignature: !!certificate.signature,
            sessionId: sessionId
          });
          
          // 处理手写签名，上传到OSS
          let signatureUrl = null;
          if (certificate.signature) {
            try {
              // 从base64字符串中提取图片数据
              const base64Data = certificate.signature.replace(/^data:image\/png;base64,/, '');
              const buffer = Buffer.from(base64Data, 'base64');
              
              // 生成唯一的文件名，包含合格证信息的标识
              const timestamp = Date.now();
              const filename = `certificate_signature_${timestamp}.png`;
              
              // 上传到OSS，指定文件夹为certificate/signatures
              signatureUrl = await OssUploader.uploadBuffer(buffer, filename, 'certificate/signatures', 'image');
              console.log('手写签名上传到OSS成功:', signatureUrl);
            } catch (error) {
              console.error('上传手写签名到OSS失败:', error.message);
              // 即使上传失败，也继续处理，将签名数据存储为base64
              signatureUrl = certificate.signature;
            }
          }
          
          // 生成查看页面的URL，包含会话ID
          const viewUrl = `http://8.137.125.67:3008/view.html?sessionId=${encodeURIComponent(sessionId)}`;
          
          // 生成二维码并上传到OSS
          let qrCodeUrl = null;
          try {
            // 使用Google Charts API生成二维码
            const qrCodeApiUrl = `https://api.qrserver.com/v1/create-qr-code/?size=300x300&data=${encodeURIComponent(viewUrl)}`;
            
            // 下载二维码图片
            const https = require('https');
            const qrCodeBuffer = await new Promise((resolve, reject) => {
              https.get(qrCodeApiUrl, (response) => {
                const chunks = [];
                response.on('data', (chunk) => chunks.push(chunk));
                response.on('end', () => resolve(Buffer.concat(chunks)));
                response.on('error', reject);
              }).on('error', reject);
            });
            
            // 生成唯一的文件名
            const timestamp = Date.now();
            const qrCodeFilename = `certificate_qrcode_${timestamp}.png`;
            
            // 上传到OSS，指定文件夹为certificate/qrcodes
            qrCodeUrl = await OssUploader.uploadBuffer(qrCodeBuffer, qrCodeFilename, 'certificate/qrcodes', 'image');
            console.log('二维码上传到OSS成功:', qrCodeUrl);
          } catch (error) {
            console.error('上传二维码到OSS失败:', error.message);
            // 即使上传失败，也继续处理
          }
          
          // 插入数据到数据库
          await pool.execute(
            'INSERT INTO certificate (company, phoneNumber, productName, grossWeight, commitBasis, origin, issueDate, signature, sessionId, qrCodeUrl) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)',
            [certificate.subjectName, certificate.contact, certificate.productName, certificate.weight, certificate.basis, certificate.origin, certificate.date, signatureUrl, certificate.sessionId, qrCodeUrl]
          );
          
          console.log('数据插入数据库成功');
          
          // 返回成功响应，确保返回的signature是OSS URL，日期只显示到日
        const responseCertificate = {
          ...certificate,
          signature: signatureUrl,
          qrCodeUrl: qrCodeUrl,
          // 格式化日期为YYYY-MM-DD格式
          date: certificate.date.toISOString().split('T')[0]
        };
        
        res.writeHead(200, { 
          'Content-Type': 'application/json',
          'Access-Control-Allow-Origin': '*',
          'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
          'Access-Control-Allow-Headers': 'Content-Type'
        });
        res.end(JSON.stringify({ success: true, certificate: responseCertificate }));
        } catch (error) {
          console.error('处理表单数据失败:', error.message);
          res.writeHead(500, { 
            'Content-Type': 'application/json',
            'Access-Control-Allow-Origin': '*',
            'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
            'Access-Control-Allow-Headers': 'Content-Type'
          });
          res.end(JSON.stringify({ success: false, error: '处理数据失败，请重试' }));
        }
      });
    } catch (error) {
      console.error('保存合格证信息失败:', error.message);
      res.writeHead(500, { 
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Methods': 'POST, GET, OPTIONS',
        'Access-Control-Allow-Headers': 'Content-Type'
      });
      res.end(JSON.stringify({ success: false, error: '保存失败，请重试' }));
    }
    return;
  }

  // 处理GET请求
  // 解析请求路径，移除查询参数
  let filePath = '.' + req.url.split('?')[0];
  if (filePath === './') {
    filePath = './certificate.html';
  }

  // 获取文件扩展名
  const extname = String(path.extname(filePath)).toLowerCase();
  
  // 定义MIME类型
  const mimeTypes = {
    '.html': 'text/html',
    '.js': 'text/javascript',
    '.css': 'text/css',
    '.json': 'application/json',
    '.png': 'image/png',
    '.jpg': 'image/jpg',
    '.gif': 'image/gif',
    '.svg': 'image/svg+xml',
    '.wav': 'audio/wav',
    '.mp4': 'video/mp4',
    '.woff': 'application/font-woff',
    '.ttf': 'application/font-ttf',
    '.eot': 'application/vnd.ms-fontobject',
    '.otf': 'application/font-otf',
    '.wasm': 'application/wasm'
  };

  // 获取对应的MIME类型
  const contentType = mimeTypes[extname] || 'application/octet-stream';

  // 读取文件
  fs.readFile(filePath, (error, content) => {
    if (error) {
      if(error.code == 'ENOENT') {
        // 文件不存在
        fs.readFile('./404.html', (error, content) => {
          res.writeHead(404, { 'Content-Type': 'text/html' });
          res.end(content, 'utf-8');
        });
      } else {
        // 服务器错误
        res.writeHead(500);
        res.end('Sorry, check with the site admin for error: ' + error.code + ' ..\n');
        res.end(); 
      }
    } else {
      // 成功读取文件
      res.writeHead(200, { 'Content-Type': contentType });
      res.end(content, 'utf-8');
    }
  });
});

// 启动服务器
server.listen(port, () => {
  console.log(`Server running at http://localhost:${port}/`);
});

console.log(`Server starting on port ${port}...`);