// Twilio Media Stream WebSocket Handler
const WebSocket = require('ws');
const wss = new WebSocket.Server({ port: 8080 });

wss.on('connection', (ws) => {
  ws.on('message', async (message) => {
    const msg = JSON.parse(message);
    
    if (msg.event === 'start') {
      console.log('Call session initiated:', msg.start.streamSid);
      // Initialize KidVox real-time child voice agent
      ws.kidvoxSession = new KidVoxAgent({
        voiceId: 'kv_mischief_leo_uk',
        sampleRate: 8000,
        characterTrait: 'spiteful_banter',
        latencyMode: 'telephony_realtime'
      });
    }

    if (msg.event === 'media') {
      const audioChunk = Buffer.from(msg.media.payload, 'base64');
      const responseStream = await ws.kidvoxSession.streamAudio(audioChunk);
      
      // Send synthesised voice packet back to caller
      ws.send(JSON.stringify({
        event: 'media',
        streamSid: msg.streamSid,
        media: { payload: responseStream.toString('base64') }
      }));
    }
  });
});