Manual WebSocket

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

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

// Configuration
const CLIENT_ID = process.env.ZOOM_CLIENT_ID;
const

{
  content_type: 2,     // 1=RTP, 2=RAW_AUDIO
  sample_rate: 1,      // 0=8kHz, 1=16kHz, 2=32kHz, 3=48kHz
  channel: 1,          // 1=Mono, 2=Stereo (OPUS only)
  codec: 1,            // 1=L16, 2=G.711, 3=G.722, 4=OPUS
  data_opt: 1,         // 1=Mixed, 2=Multi-streams
  send_rate: 20        // Chunk size in ms (multiple of 20)
}

function subscribeToParticipantVideo(streamId, userId) {
  const signalingWs = signalingConnections.get(streamId);
  if (!signalingWs) return;

  signalingWs.send(JSON.stringify({
    msg_type: 28, // VIDEO_SUBSCRIPTION_REQ
    user_id: userId,
    subscribe: true,
    timestamp: Date.now()
  }));
}

function closeStream(streamId) {
  const signalingWs = signalingConnections.get(streamId);
  if (!signalingWs) return;

  signalingWs.send(JSON.stringify({
    msg_type: 21, // STREAM_CLOSE_REQ
    rtms_stream_id: streamId
  }));
}

{
  content_type: 3,     // 3=RAW_VIDEO
  codec: 7,            // 5=JPG, 6=PNG, 7=H.264
  resolution: 2,       // 1=SD, 2=HD, 3=FHD, 4=QHD
  fps: 25,             // 1-30 (JPG/PNG max 5)
  data_opt: 3          // 3=Single active speaker
}

{
  content_type: 3,     // 3=RAW_VIDEO
  codec: 5,            // 5=JPG, 6=PNG, 7=H.264
  resolution: 3,       // 1=SD, 2=HD, 3=FHD, 4=QHD
  fps: 1               // 1-30 (JPG/PNG max 1)
}

{
  content_type: 5,     // 5=TEXT
  src_language: 9,     // 9=English
  enable_lid: false    // Fixed language, no auto-switch
}

// Implement exponential backoff for reconnection
let retryDelay = 1000;

ws.on('close', (code, reason) => {
  console.log('Connection closed:', code, reason);
  
  // Don't reconnect if intentionally closed
  if (code === 1000) return;
  
  setTimeout(() => {
    reconnect();
  }, retryDelay);
  
  retryDelay = Math.min(retryDelay * 2, 30000);
});

ws.on('error', (error) => {
  console.error('WebSocket error:', error);
  // Connection will close, triggering reconnection
});

function handleAudioData(msg, streamId) {
  const now = msg.timestamp;
  const last = lastTimestamps.get(streamId) || now;
  const gap = now - last;
  
  // Fill gaps >= 500ms with silence
  if (gap >= 500) {
    const silentFrames = Math.floor(gap / 20);
    console.log(`Filling ${silentFrames} silent frames`);
    
    for (let i = 0; i < silentFrames; i++) {
      const silentFrame = Buffer.alloc(640); // 20ms @ 16kHz mono
      writeToFile(silentFrame);
    }
  }
  
  lastTimestamps.set(streamId, now);
  
  const audioBuffer = Buffer.from(msg.content, 'base64');
  writeToFile(audioBuffer);
}