const http = require('http');
const fs = require('fs');
const { MongoClient } = require('mongodb');
const path = require('path');

const PORT = 3002;
const MONGO_URI = 'mongodb://localhost:27017';

let db;

async function connectDB() {
  const client = new MongoClient(MONGO_URI);
  await client.connect();
  db = client.db('oktopus');
  console.log('Connected to MongoDB');
}

const server = http.createServer(async (req, res) => {
  if (req.url === '/api/monitor/devices') {
    try {
      const devices = await db.collection('devices').find({}).toArray();
      res.writeHead(200, { 'Content-Type': 'application/json' });
      res.end(JSON.stringify(devices));
    } catch (e) {
      res.writeHead(500); res.end(JSON.stringify({ error: e.message }));
    }
  } else {
    // Serve static files
    let filePath = req.url === '/' ? '/index.html' : req.url;
    filePath = path.join(__dirname, filePath);
    try {
      const content = fs.readFileSync(filePath);
      const ext = path.extname(filePath);
      const types = { '.html': 'text/html', '.css': 'text/css', '.js': 'application/javascript' };
      res.writeHead(200, { 'Content-Type': types[ext] || 'text/plain' });
      res.end(content);
    } catch {
      res.writeHead(404); res.end('Not found');
    }
  }
});

connectDB().then(() => {
  server.listen(PORT, () => console.log(`Device Monitor: http://localhost:${PORT}`));
});