// Node.js 22+. Install: npm install pg standardwebhooks
// Run webhook-inbox.sql in your application's database first.
// DATABASE_URL and WEBHOOK_SECRET must be set in your server environment.
import http from 'node:http';
import pg from 'pg';
import { Webhook } from 'standardwebhooks';
if (!process.env.DATABASE_URL || !process.env.WEBHOOK_SECRET) throw new Error('Database and signing secret required');
const pool = new pg.Pool({ connectionString: process.env.DATABASE_URL, connectionTimeoutMillis: 3000, statement_timeout: 5000 });
const verifier = new Webhook(process.env.WEBHOOK_SECRET);
const server = http.createServer(async (request, response) => {
  const reply = status => { response.writeHead(status); response.end(); };
  if (request.method !== 'POST' || request.url !== '/webhook') return reply(404);
  try {
    const parts = []; let size = 0;
    for await (const part of request) {
      size += part.length;
      if (size > 262144) return reply(413);
      parts.push(part);
    }
    const raw = Buffer.concat(parts).toString('utf8');
    let event;
    try { event = verifier.verify(raw, request.headers); } catch { return reply(401); }
    const id = request.headers['webhook-id'];
    if (typeof id !== 'string' || id.length > 200 || !event || typeof event !== 'object' || typeof event.type !== 'string') return reply(400);
    await pool.query(
      'INSERT INTO email_webhook_inbox(source,event_id,payload) VALUES($1,$2,$3::jsonb) ON CONFLICT DO NOTHING',
      ['postrune-endpoint-1', id, JSON.stringify(event)],
    );
    // Success only after the durable write. Duplicates get the same response.
    reply(204);
  } catch {
    reply(503); // Provider may retry; never acknowledge an uncommitted event.
  }
});
server.requestTimeout = 5000;
server.headersTimeout = 5000;
// Set WEBHOOK_PORT=0 to choose an available local port for a test run.
const port = Number(process.env.WEBHOOK_PORT ?? 3028);
server.listen(port, '127.0.0.1', () => console.log(`Local webhook inbox: http://127.0.0.1:${server.address().port}`));