// wrt + socket + contrl
const io = require("socket.io-client")
const RTCVideoSource = require('./lib/videoSource')
//const PWM = require('./lib/Pwm')
const { RTCPeerConnection, MediaStream } = require("wrtc")
const HOST = 'ws://10.10.3.196:7896'
class CarServer {
    constructor(HOST) {
        this.webRTC = null
        this.mediaStream = null
        this.videoSource = null     
        this.socket = io(HOST, {
            auth: {
                roomID: "feiCar",
                name: 'car'
            }
        });
        this.socket.on('connect', () => {
            this.connect()
        })
        this.socket.on('leaved', user => {
            console.log(`${user.name}离开${user.roomID}房间`)
            // 用户离开移除RTC
            this.destroyed()
        })
        this.socket.on('joined', user => {
            console.log(`${user.name}加入${user.roomID}房间`)
            // 发送offer
            this.createOffer()
        })
        this.socket.on('msg', data => {
            console.log('用户信息', data.type);
            this.msg(data)
        })
        this.socket.on('connect_error', err => {
            console.log('连接错误', err)
            this.destroyed()
        })
    }
    // 连接
    connect() {
        console.log('连接成功,开始初始化webrtc')
        // 初始化rtc
        this.webRTC = new RTCPeerConnection()
        // 初始化媒体源
        this.mediaStream = new MediaStream()
        this.videoSource = new RTCVideoSource()
        // 加入媒体源
        const videoTrack = this.videoSource.createTrack()
        this.mediaStream.addTrack(videoTrack)
        this.webRTC.addTrack(videoTrack, this.mediaStream)
        // 开始媒体
        this.videoSource.start()
        // 监听ice
        this.webRTC.onicecandidate = event => {
            if (event.candidate) {
                // 发送ICE
                this.socket.emit('msg', {
                    type: 'candidate',
                    candidate: event.candidate
                })
            }
        }
        // 监听ice状态
        this.webRTC.oniceconnectionstatechange = () => {
            if (this.webRTC.iceConnectionState === 'failed' || this.webRTC.iceConnectionState === 'closed' || this.webRTC.iceConnectionState === "disconnected") {
                console.log('ICE 连接失败')
                this.destroyed()
            }
        }        
    }
    // 用户信息
    msg(data){
        if (data.type === 'answer') {
            // 设置本地应答
            this.webRTC.setRemoteDescription(data.answer)
        } else if (data.type === 'candidate') {
            // 本地设置ICE
            this.webRTC.addIceCandidate(data.candidate)
        } else if (data.type === 'conctrl') {
            // 控制信息
            //PWM.changPWM(data.conctrl)
        } else if (data.type === 'startRTC') {
            // 向其它房间人发送offer
            this.createOffer()
        }
    }
    // 创建offer
    async createOffer() {
        // 创建offer
        const offer = await this.webRTC.createOffer()
        this.webRTC.setLocalDescription(offer)
        // 发送offer
        this.socket.emit('msg', {
            type: 'offer',
            offer: offer
        })
    }

    destroyed() {
        if (this.webRTC) this.webRTC.close()
        if (this.videoSource) this.videoSource.stop()
        this.webRTC = null
        this.mediaStream = null
        this.videoSource = null     
        process.exit(1) 
    }    
}
new CarServer(HOST)