const ffmpegPath = require('@ffmpeg-installer/ffmpeg');
const ffmpeg = require('fluent-ffmpeg');
const websocketStream = require('websocket-stream/stream');
const WebSocket = require('ws');

const SERVER="http://8.142.135.163:8100";
const PROXY_ID="wx-mixc-01"

const url = `${SERVER}/proxy?proxyId=${PROXY_ID}`;
let retryTimeout = 1000; // 初始重连间隔时间 (毫秒)

ffmpeg.setFfmpegPath(ffmpegPath.path);

function processFFmpeg(event) {
     console.log('process ffmpeg')
     const pushUrl = `${SERVER}/push?connectId=${event.connectId}`
     const ws = websocketStream(pushUrl, { websocket: WebSocket });

     function processEvent(event) {
          const rtsp = event.payload.rtsp
          try {
               ffmpeg(rtsp)
                    .addInputOption(
                         '-rtsp_transport', 'tcp',
                         '-buffer_size', '102400'
                    )
                    .on('start', (commandLine) => {
                         console.log('code start');
                    })
                    .on('codecData', function (data) {
                         console.log(data, '');
                    })
                    .on('progress', function (progress) {
                         // console.log(progress,'转码进度')
                    })
                    .on('error', function (err, a, b) {
                         console.log(url, '转码 错误: ', err.message);
                         console.log('输入错误', a);
                         console.log('输出错误', b);
                    })
                    .on('end', function () {
                         console.log(url, '转码 结束!');
                    })
                    .addOutputOption(
                         '-threads', '4',  // 一些降低延迟的配置参数
                         '-tune', 'zerolatency',
                         '-preset', 'ultrafast'
                    )
                    .outputFormat('flv') // 转换为flv格式
                    .videoCodec('libx264') // ffmpeg无法直接将h265转换为flv的，故需要先将h265转换为h264，然后再转换为flv
                    .withSize('25%') // 转换之后的视频分辨率原来的50%, 如果转换出来的视频仍然延迟高，可按照文档上面的描述，自行降低分辨率
                    .noAudio() // 去除声音
                    .pipe(ws,{ end: true });
               
          } catch (error) {
               console.log('抛出异常', error);
          }
     }

     ws.on('connect', () => {
          processEvent(event)
          console.log('connnected to send rtsp stream')
     })

     ws.on('close',()=>{
          console.log('disconnect push stream')
     })
}

function connect() {
     const ws = websocketStream(url, { websocket: WebSocket });

     ws.on('connect', () => {
          console.log('已连接到 WebSocket 服务器:', url);
          retryTimeout = 1000; // 连接成功后重置重试时间
     });

     // 监听接收到的消息
     ws.on('data', (data) => {
          const event = JSON.parse(data.toString())
          console.log('event：', event)
          if (event.action == 'connected') {
               processFFmpeg(event)
          }
     });

     // 监听错误
     ws.on('error', (error) => {
          console.error('WebSocket 错误:', error);
     });

     // 监听连接关闭事件并重试
     ws.on('close', () => {
          console.log('连接已断开，尝试重新连接...');
          ws.end();

          // 使用指数回退算法增加重连时间间隔
          setTimeout(connect, retryTimeout);
          retryTimeout = Math.min(retryTimeout * 2, 30000); // 最大重试间隔 30 秒
     });

     ws.write('Hello, WebSocket Server!');
}

// 初次连接
connect();