const { MediaStreamTrack, randomPort, RTCPeerConnection, RTCRtpCodecParameters, RtpPacket } = require('werift')
const { Server } = require('ws')
const { createSocket } = require('dgram')
const { exec } = require('child_process')


// open answer.html

const server = new Server({ port: 8888 });
console.log("start");

server.on("connection", async (socket) => {
  console.log('客户端连接');
  const payloadType = 96;
  const pc = new RTCPeerConnection({
    codecs: {
      audio: [],
      video: [
        new RTCRtpCodecParameters({
          mimeType: "video/VP8",
          clockRate: 90000,
          payloadType: payloadType,
          // rtcpFeedback: [
          //   { type: "ccm", parameter: "fir" },
          //   { type: "nack" },
          //   { type: "nack", parameter: "pli" },
          //   { type: "goog-remb" },
          // ]          
        }),
      ],
    },
    iceServers: [
      {
        urls: [
          "stun:caner.top:3478"
        ],
      },
      {
        urls: "turn:caner.top:3478",
        username: "admin",
        credential: "123456",
      },
    ]
  });

  const track = new MediaStreamTrack({ kind: "video" })

  randomPort().then((port) => {
    const udp = createSocket("udp4");
    udp.bind(port);
    console.log('端口',port);
    // linux 
    exec(`ffmpeg -re -f v4l2 -i /dev/video0 -pix_fmt yuv420p -s 320x240 -vcodec h264 -preset veryfast -g 1 -f rtp rtp://127.0.0.1:${port}`, (error, stdout, stderr) => {
      if (error) {
        console.error(`exec error: ${error}`);
        return;
      }
    })   

    udp.on("message", (data) => {
      const rtp = RtpPacket.deSerialize(data);
      rtp.header.payloadType = payloadType;
      track.writeRtp(rtp);
    });
  });


  pc.addTransceiver(track, { direction: "sendonly" });


  await pc.setLocalDescription(await pc.createOffer());
  const sdp = JSON.stringify(pc.localDescription);
  socket.send(sdp);

  socket.on("message", (data) => {
    pc.setRemoteDescription(JSON.parse(data));
  });
});