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/h264",
          clockRate: 90000,
          payloadType: payloadType,
        }),
      ],
    },
    iceServers: [
      // {
      //   urls: [
      //     "stun:caner.top:3478",
      //     "stun:stun.l.google.com:19302",
      //     "stun:stun1.l.google.com:19302",
      //     "stun:stun2.l.google.com:19302",
      //     "stun:stun3.l.google.com:19302",
      //   ],
      // },
      // {
      //   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);
    // test vp8
    /**
     * -lavfi 定义一个复杂的过滤器图
     */
    // exec(`D:/ffmpeg-4.4-full_build/bin/ffmpeg.exe -re -f lavfi -i testsrc=size=640x480:rate=30 -vcodec libvpx -cpu-used 5 -deadline 1 -g 10 -error-resilient 1 -auto-alt-ref 1 -f rtp rtp://127.0.0.1:${port}`,(error, stdout, stderr) => {
    //   if (error) {
    //     console.error(`exec error: ${error}`);
    //     return;
    //   }
    //   console.log(`stdout: ${stdout}`);
    //   console.error(`stderr: ${stderr}`);
    // })

    // win video h264
    /**
     * -re 以原生帧速率读取输入
     * -f 强制格式
     * dshow 直接捕获视频
     * -s 视频大小
     * -discard 在输入之前丢弃帧（noref：丢弃非参考帧，bidir：丢弃双向帧，nokey：丢弃非关键帧）
     * -xerror 出错时停止并退出
     * -i 输入
     * -pix_fmt 视频格式
     * -c 在输入之后是编码，在输入之前是解码
     * -vstats 视频日志
     * rtp 输出格式
     */
    exec(`D:/ffmpeg-4.4-full_build/bin/ffmpeg.exe -re -f dshow -s 640x480 -discard nokey -xerror -i video="Logitech HD Webcam C525" -pix_fmt yuv420p -c h264 -vstats -cpu-used 10 -g 5 -preset ultrafast -tune zerolatency -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));
  });
});