White-Label API Integration

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

const app = express();
app.use(express.json());

const STEMSPLIT_API_KEY = process.env.STEMSPLIT_API_KEY;
const WEBHOOK_SECRET = process.env.STEMSPLIT_WEBHOOK_SECRET;

// Store job -> user mapping (use your database in production)
const jobUserMap = new Map();

// 1. Your user requests stem separation
app.post('/api/separate', async (req, res) => {
  const { userId, audioUrl, outputType } = req.body;
  
  try {
    // Create job with StemSplit
    const response = await axios.post(
      'https://stemsplit.io/api/v1/jobs',
      {
        sourceUrl: audioUrl,
        outputType: outputType || 'ALL_STEMS',
        quality: 'BEST',
        outputFormat: 'MP3'
      },
      { headers: { 'Authorization': `Bearer ${STEMSPLIT_API_KEY}` }}
    );
    
    const jobId = response.data.id;
    
    // Map job to user for webhook handling
    jobUserMap.set(jobId, userId);
    
    // Return job ID to your frontend
    res.json({ 
      jobId,
      status: 'processing',
      message: 'Your audio is being processed'
    });
    
  } catch (error) {
    res.status(500).json({ error: 'Failed to start processing' });
  }
});

// 2. Handle webhooks from StemSplit
app.post('/webhooks/stemsplit', (req, res) => {
  // Verify webhook signature
  const signature = req.headers['x-webhook-signature'];
  const expectedSig = crypto
    .createHmac('sha256', WEBHOOK_SECRET)
    .update(JSON.stringify(req.body))
    .digest('hex');
  
  if (signature !== expectedSig) {
    return res.status(401).json({ error: 'Invalid signature' });
  }
  
  const { event, data } = req.body;
  const userId = jobUserMap.get(data.jobId);
  
  if (event === 'job.completed') {
    // Notify your user (websocket, email, push notification, etc.)
    notifyUser(userId, {
      type: 'stem_separation_complete',
      outputs: data.outputs
    });
    
    // Clean up
    jobUserMap.delete(data.jobId);
  }
  
  if (event === 'job.failed') {
    notifyUser(userId, {
      type: 'stem_separation_failed',
      error: data.error
    });
    jobUserMap.delete(data.jobId);
  }
  
  res.json({ received: true });
});

// 3. Let users check job status
app.get('/api/jobs/:jobId', async (req, res) => {
  const { jobId } = req.params;
  
  const response = await axios.get(
    `https://stemsplit.io/api/v1/jobs/${jobId}`,
    { headers: { 'Authorization': `Bearer ${STEMSPLIT_API_KEY}` }}
  );
  
  res.json(response.data);
});

function notifyUser(userId, data) {
  // Implement your notification logic
  // WebSocket, email, push notification, etc.
  console.log(`Notifying user ${userId}:`, data);
}

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