import 'dart:convert';

import 'package:flutter_webrtc/flutter_webrtc.dart';
import 'package:job_app/singletons/user_info.dart';
import 'package:web_socket_channel/web_socket_channel.dart';
typedef void StreamStateCallback(MediaStream stream);

class Signaling{
  Map<String, dynamic> configuration = {
    'iceServers': [
      {
        'urls': [
          'stun:stun.stunprotocol.org:3478',
          'stun:stun.l.google.com:19302' ,
        ]
      }
    ]
  };
  WebSocketChannel channel;
  RTCPeerConnection peerConnection;
  MediaStream localStream;
  MediaStream remoteStream;
  String roomId;
  String currentRoomText;
  StreamStateCallback onAddRemoteStream;


  Future<void> connectToWS()async{
    channel = WebSocketChannel.connect(
      Uri.parse('wss://server.thejob.net/signaling'),
    );
    channel.sink.add('{"fromuser":"${userInfo.user.id}","too":"153803","sdp":null,"candidate":null,"type":"join","data":"1538031640620283243"}');
  }


  Future<void> openUserMedia(
      RTCVideoRenderer localVideo,
      RTCVideoRenderer remoteVideo,
      ) async {
    await localVideo.initialize();
    await remoteVideo.initialize();
    var stream = await navigator.mediaDevices
        .getUserMedia({'video': true, 'audio': false});

    localVideo.srcObject = stream;
    localStream = stream;

    remoteVideo.srcObject = await createLocalMediaStream('key');
  }


  Future<void> peerConnecting(Map sockRes, RTCVideoRenderer remoteRenderer)async{
    peerConnection = await createPeerConnection(configuration);
    registerPeerConnectionListeners();
    peerConnection.addStream(localStream);

    peerConnection.onTrack= (RTCTrackEvent event){
      print('Got remote track: ${event.streams[0]}');
      event.streams[0].getTracks().forEach((track) {
        print('Add a track to the remoteStream: $track');
        remoteStream.addTrack(track);
      });
    };
    peerConnection.onIceCandidate = (RTCIceCandidate candidate) {
      if (candidate == null) {
        print('onIceCandidate: complete!');
        return;
      }
      print('onIceCandidate: ${candidate.toMap()}');
    };
    //code for create answer and set Remote desc
    if(sockRes["type"]=="new_offer"){
      Map desc = jsonDecode(sockRes["sdp"]);
      await peerConnection?.setRemoteDescription(
        RTCSessionDescription(desc['sdp'], 'offer'),
      );
      var answer = await peerConnection.createAnswer();
      await peerConnection.setLocalDescription(answer);
      channel.sink.add('{"fromuser":"${userInfo.user.id}","too":"153803","sdp":${jsonEncode(answer.sdp)},"candidate":null,"type":"answer","data":"1538031640620283243"}');
    }

    //code for set candidates
    if(sockRes["type"]=="new_ice"){
      String jsonString = sockRes["candidate"];
      dynamic session = await jsonDecode(jsonString);
      peerConnection.addCandidate(
        RTCIceCandidate(
          session['candidate'],
          session['sdpMid'],
          session['sdpMLineIndex'],
        ),
      );
    }

  }

  void registerPeerConnectionListeners() {
    peerConnection?.onIceGatheringState = (RTCIceGatheringState state) {
      print('ICE gathering state changed: $state');
    };

    peerConnection?.onConnectionState = (RTCPeerConnectionState state) {
      print('Connection state change: ${peerConnection.connectionState}');
    };

    peerConnection?.onSignalingState = (RTCSignalingState state) {
      print('Signaling state change: $state');
    };

    peerConnection?.onIceGatheringState = (RTCIceGatheringState state) {
      print('ICE connection state change: $state');
    };

    peerConnection?.onAddStream = (MediaStream stream) {
      print("Add remote stream");
      onAddRemoteStream?.call(stream);
      remoteStream = stream;
    };
  }

  Future<void> cleanSession(RTCVideoRenderer renderer)async{
    if (localStream != null) {
      renderer.srcObject.getTracks().forEach((element) async {
        await element.stop();
      });
      await renderer.srcObject.dispose();
      renderer.srcObject = null;
    }
  }
}