Webhooks e Notificações

const express = require('express');
const crypto = require('crypto');

const app = express();
app.use(express.json({ limit: '10mb' }));

// Middleware para capturar raw body
app.use('/webhooks', (req, res, next) => {
  req.rawBody = JSON.stringify(req.body);
  next();
});

app.post('/webhooks/vozparatexto', async (req, res) => {
  try {
    // Verificar assinatura
    const signature = req.headers['x-vozparatexto-signature'];
    if (!verifySignature(req.rawBody, signature)) {
      return res.status(401).json({ error: 'Invalid signature' });
    }

    const { event, data } = req.body;

    // Responder rapidamente
    res.status(200).json({ received: true });

    // Processar evento assincronamente
    await processEvent(event, data);
    
  } catch (error) {
    console.error('Webhook error:', error);
    res.status(500).json({ error: 'Internal server error' });
  }
});

async function processEvent(event, data) {
  switch (event) {
    case 'transcription.completed':
      await handleTranscriptionCompleted(data);
      break;
    case 'transcription.failed':
      await handleTranscriptionFailed(data);
      break;
    case 'credits.low':
      await handleCreditsLow(data);
      break;
    default:
      console.log('Unknown event:', event);
  }
}

function verifySignature(payload, signature) {
  const secret = process.env.WEBHOOK_SECRET;
  if (!secret || !signature) return false;
  
  const expectedSignature = crypto
    .createHmac('sha256', secret)
    .update(payload, 'utf8')
    .digest('hex');
    
  const receivedSignature = signature.replace('sha256=', '');
  
  return crypto.timingSafeEqual(
    Buffer.from(expectedSignature, 'hex'),
    Buffer.from(receivedSignature, 'hex')
  );
}

<?php

// webhook-handler.php
$secret = getenv('WEBHOOK_SECRET');
$signature = $_SERVER['HTTP_X_VOZPARATEXTO_SIGNATURE'] ?? '';
$payload = file_get_contents('php://input');

// Verificar assinatura
if (!verifySignature($payload, $signature, $secret)) {
    http_response_code(401);
    exit('Invalid signature');
}

// Decodificar payload
$data = json_decode($payload, true);
if (!$data) {
    http_response_code(400);
    exit('Invalid JSON');
}

// Responder rapidamente
http_response_code(200);
echo json_encode(['received' => true]);

// Processar evento
processEvent($data['event'], $data['data']);

function verifySignature($payload, $signature, $secret) {
    if (empty($secret) || empty($signature)) {
        return false;
    }
    
    $expectedSignature = hash_hmac('sha256', $payload, $secret);
    $receivedSignature = str_replace('sha256=', '', $signature);
    
    return hash_equals($expectedSignature, $receivedSignature);
}

function processEvent($event, $data) {
    switch ($event) {
        case 'transcription.completed':
            handleTranscriptionCompleted($data);
            break;
        case 'transcription.failed':
            handleTranscriptionFailed($data);
            break;
        case 'credits.low':
            handleCreditsLow($data);
            break;
        default:
            error_log("Unknown webhook event: $event");
    }
}

function handleTranscriptionCompleted($data) {
    // Implementar lógica de processamento
    $transcriptionId = $data['id'];
    $result = $data['result'];
    
    // Exemplo: salvar no banco de dados
    // updateTranscriptionStatus($transcriptionId, 'completed', $result);
    
    // Exemplo: enviar email para usuário
    // sendCompletionEmail($transcriptionId);
}

?>