const express = require('express');
const cors = require('cors');
const mysql = require('mysql');

const app = express();
const port = 8000;

// 允许所有来源的请求
app.use(cors());

// 创建 MySQL 连接
const db = mysql.createConnection({
  host: '172.17.0.1',
  user: 'RQteafactory',
  password: 'Guoswork105',
  database: 'RQteafactory'
});

// 连接数据库
db.connect((err) => {
  if (err) {
    console.error('MySQL connection error: ', err);
    return;
  }
  console.log('MySQL connected...');
});

// 折线图获取数据库数据
function getSensorData(callback) {
  const sql = 'SELECT timestamp, temperature, humidity, co2, pressure FROM sensor_data';
  db.query(sql, (err, results) => {
    if (err) {
      console.error('Error fetching sensor data: ', err);
      callback({ error: 'Error fetching sensor data' });
      return;
    }

    const timestamps = results.map(row => new Date(row.timestamp).toISOString().slice(0, 19).replace('T', ' '));
    const temperatures = results.map(row => row.temperature);
    const humidities = results.map(row => row.humidity);
    const co2 = results.map(row => row.co2);
    const pressure = results.map(row => row.pressure);

    callback({
      timestamps,
      temperatures,
      humidities,
      co2,
      pressure
    });
  });
}

// 获取数据库中最新的数据
function getLatestSensorData(callback) {
  const sql = 'SELECT temperature, humidity, co2, pressure FROM sensor_data ORDER BY timestamp DESC LIMIT 1';
  db.query(sql, (err, results) => {
    if (err) {
      console.error('Error fetching latest sensor data: ', err);
      callback({ error: 'Error fetching latest sensor data' });
      return;
    }

    const data = results[0];
    callback({
      temperature: data.temperature,
      humidity: data.humidity,
      co2: data.co2,
      pressure: data.pressure
    });
  });
}

// 获取数据
app.get('/get_sensor_data', (req, res) => {
  getSensorData(data => {
    res.json(data);
  });
});

// 获取最新的数据
app.get('/get_latest_sensor_data', (req, res) => {
  getLatestSensorData(data => {
    res.json(data);
  });
});

// 启动服务器
app.listen(port, () => {
  console.log(`Server running on http://0.0.0.0:${port}`);
});