// =========================
// WebSocket Twilio <-> OpenAI Realtime
// =========================
import WebSocket, { WebSocketServer } from 'ws';
import fs from 'fs-extra';
import path from 'path';
import { OpenAI } from 'openai';

const PORT = 8089;
const PROMPT_DIR = path.resolve('./prompts');
const LOG_DIR = path.resolve('./logs');

fs.ensureDirSync(PROMPT_DIR);
fs.ensureDirSync(LOG_DIR);

const wss = new WebSocketServer({ port: PORT });
console.log(`WebSocket server running on ws://localhost:${PORT}`);

// OpenAI Realtime
const openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY });
if (!process.env.OPENAI_API_KEY) {
  console.error("⚠️ Définir OPENAI_API_KEY dans les variables d'environnement !");
  process.exit(1);
}

wss.on('connection', async (ws, req) => {
  const callSid = new URLSearchParams(req.url.split('?')[1]).get('callSid') || 'TEST';
  console.log(`Nouvelle connexion pour callSid=${callSid}`);

  // Charger le prompt initial
  let prompt = {};
  const promptFile = path.join(PROMPT_DIR, `${callSid}.json`);
  if (fs.existsSync(promptFile)) prompt = fs.readJsonSync(promptFile);

  // Créer session Realtime OpenAI (ChatGPT + TTS)
  const session = await openai.realtime.sessions.create({
    model: "gpt-5o-realtime-preview",
    voice: "alloy" // voix ChatGPT
  });

  // Gestion audio entrant Twilio
  ws.on('message', async (msg) => {
    const data = JSON.parse(msg);

    if (data.event === 'media') {
      const audio = Buffer.from(data.media.payload, 'base64');

      // Envoyer audio à OpenAI
      try {
        await session.sendAudio(audio); // stream vers ChatGPT
      } catch (err) {
        console.error(`Erreur sendAudio: ${err.message}`);
      }
    }
  });

  // Réception texte/TTS d’OpenAI
  session.on('transcript', (text) => {
    console.log(`[${callSid}] Transcript: ${text}`);
    logEvent(callSid, { type: 'transcript', text });
  });

  session.on('audio', (audioBuffer) => {
    ws.send(JSON.stringify({
      event: 'media',
      media: { payload: audioBuffer.toString('base64') }
    }));
  });

  ws.on('close', () => {
    console.log(`Connexion fermée pour callSid=${callSid}`);
  });
});

// Fonction utilitaire pour logs
function logEvent(callSid, event) {
  const logFile = path.join(LOG_DIR, `${callSid}.json`);
  let logs = [];
  if (fs.existsSync(logFile)) logs = fs.readJsonSync(logFile);
  logs.push({ timestamp: Date.now(), ...event });
  fs.writeJsonSync(logFile, logs, { spaces: 2 });
}