// server.js
const express = require('express');
const app = express();
app.use(express.json());

app.get('/webhook', (req, res) => {
  const { ['hub.mode']: mode, ['hub.verify_token']: token, ['hub.challenge']: challenge } = req.query;
  if (mode === 'subscribe' && token === process.env.VERIFY_TOKEN) return res.status(200).send(challenge);
  res.sendStatus(403);
});

app.post('/webhook', async (req, res) => {
  const body = req.body;
  if (body.object === 'instagram') {
    for (const entry of body.entry || []) {
      for (const event of entry.messaging || []) {
        await handleMessage(event);
      }
    }
    return res.status(200).send('EVENT_RECEIVED');
  }
  res.sendStatus(404);
});

app.listen(3000, () => console.log('Webhook running on 3000'));