import Config from "./config";

class WebRtc {
    private mediaStream: MediaStream | Blob | null = null;
    private pee: RTCPeerConnection | null = null;
    private ws: WebSocket | null = null;
    private video: HTMLVideoElement | null = null;
    private userToId: string = "";
    open = () => {
        this.ws?.send(JSON.stringify({
            type: "new", "data": {
                "name": "admin",
                "id": "31283192",
                "user_agent": "flutter-webrtc/js"
            }
        }))
    }
    async init() {
        this.ws = new WebSocket(Config.rtc)
        this.ws.addEventListener('open', this.open);
        let that = this;
        this.createOffer()
        this.ws.onmessage = function (evt) {
            let msg = JSON.parse(evt.data)
            if (!msg) {
                return console.log('failed to parse msg')
            }
            switch (msg.type) {
                case 'offer':
                    let offer = msg.data.description
                    that.pee?.setRemoteDescription(offer)
                    that.pee?.createAnswer().then(answer => {
                        that.pee?.setLocalDescription(answer)
                        that.ws?.send(JSON.stringify({
                            type: 'answer', data: {
                                'to': msg.data.from,
                                'from': "31283192",
                                'description': { 'sdp': answer.sdp, 'type': answer.type },
                                'session_id': msg.data.from + "-31283192",
                            }
                        }))
                    })
                    return

                case 'candidate':
                    let candidate = msg.data.candidate
                    if (!candidate) {
                        return console.log('failed to parse candidate')
                    }
                    that.pee?.addIceCandidate(candidate)
                    break;
                case "answer":
                    that.pee?.setRemoteDescription(msg.data.description)
                    break;
                case "bye":
                    that.pee?.close()
                    that.close()
                    break;
            }
        }
    }
    async createOffer() {

        var url =
            'http://rw.quwanya.cn:12217/api/turn?service=turn&username=flutter-webrtc';
        fetch(url)
            .then(response => response.json())
            .then(data => {
                
                const configuration = {
                    iceServers: [
                        {
                            urls: data.uris[0],
                            "username": data.username,
                            "credential": data.password
                        },
                    ]
                }
                this.gets(configuration)
            })
        try {

        } catch (error) {
            console.log(error);
        }
    }

    async gets(configuration) {
        console.log(configuration);
        const peerConnection = new RTCPeerConnection(configuration);
        this.pee = peerConnection
        // 获取远方流添加到页面播放
        peerConnection.ontrack = event => {
            const remoteVideo = document.querySelector('#remoteVideo') as HTMLVideoElement;
            remoteVideo.autoplay = true
            remoteVideo.controls = true
            remoteVideo.srcObject = event.streams[0];
            console.log(event);
            
            event.track.onmute = function () {
                remoteVideo.play()
            }
        };
        await this.getMedia(peerConnection)

        peerConnection.onicecandidate = e => {
            if (!e.candidate) {
                return
            }
            this.ws?.send(JSON.stringify({ type: 'candidate', data: e }))
        }
    }
    sendOffer(userId) {
        let that = this;
        that.userToId = userId;
        that.video = document.getElementById('rtcVideo') as HTMLVideoElement;
        if (that.pee?.connectionState === "closed") {
            that.createOffer()
        }
        that.pee?.createOffer().then(function (offer) {
            that.pee?.setLocalDescription(offer);
            that.ws?.send(JSON.stringify({
                type: "offer", "data": {
                    "to": userId,
                    "from": "31283192",
                    "description": offer,
                    "media": "video",
                    "session_id": userId + "-31283192",
                }
            }))
        }).catch(function (error) {
            // 错误处理
            console.error(error);
        });
    }
    addIceCandidate(candidate) {
        this.pee?.addIceCandidate(candidate)
    }
    async getMedia(pee: RTCPeerConnection) {
        try {
            const stream = await navigator.mediaDevices.getUserMedia({
                video: true,
                audio: true
            });
            this.mediaStream = stream;
            stream.getTracks().forEach(track => pee.addTrack(track, stream))
        } catch (error) {
            console.log(error);
        }
    }
    calls(userId) {
        this.sendOffer(userId)
        if (this.video) {
            this.video.srcObject = this.mediaStream;
            this.video.autoplay = true;
        }
    }


    close() {
        this.video?.pause();
        this.pee?.close();
        this.ws?.send(JSON.stringify({
            "type": "bye", "data": {
                "session_id": this.userToId + "31283192",
                "to": this.userToId
            }
        }
        ));
        (this.mediaStream as MediaStream)?.getTracks().forEach(track => track.stop());
        this.ws?.close()
    }
}

export const webRTC = new WebRtc()