Igor

function startPresenter(sessionId, ws, sdpOffer, callback) {
  clearCandidatesQueue(sessionId);

  if (presenter !== null) {
    stop(sessionId);
    return callback("Another user is currently acting as presenter. Try again later ...");
  }

  presenter = {
    id: sessionId,
    pipeline: null,
    webRtcEndpoint: null
  };

  getKurentoClient(function (error, kurentoClient) {
    if (error) {
      stop(sessionId);
      return callback(error);
    }

    if (presenter === null) {
      stop(sessionId);
      return callback(noPresenterMessage);
    }


    kurentoClient.create('MediaPipeline', function (error, pipeline) {
      if (error) {
        stop(sessionId);
        return callback(error);
      }

      if (presenter === null) {
        stop(sessionId);
        return callback(noPresenterMessage);
      }

      presenter.pipeline = pipeline;
      var elements =
      [
        {type: 'RecorderEndpoint', params: {
          stopOnEndOfStream: true,
          //@todo add a node identifier to the filename
          uri : 'file:///tmp/podcast-.webm',
          mediaProfile : 'MP4_AUDIO_ONLY'
        }},
        {type: 'WebRtcEndpoint', params: {}},
        {type: 'PlayerEndpoint', params: {
          // mediaPipeline: presenter.pipeline,
          uri : 'http://ic-test.surge.sh/cut.mp3',
          useEncodedMedia : true
        }}
      ];

      presenter.pipeline.create(elements, function (error, elements) {
        if (error) {
          stop(sessionId);
          console.log(5)
          return callback(error);
        }

        recorder = elements[0];
        player = elements[2];

        var webRtcEndpoint = elements[1];

        if (presenter === null) {
          stop(sessionId);
          console.log(6)
          return callback(noPresenterMessage);
        }


        pipeline.create("Composite", function(error, _composite) {
          if (error) return onerror(error);
          composite = _composite;
        });

        presenter.webRtcEndpoint = webRtcEndpoint;

        if (candidatesQueue[sessionId]) {
          while (candidatesQueue[sessionId].length) {
            var candidate = candidatesQueue[sessionId].shift();
            webRtcEndpoint.addIceCandidate(candidate);
          }
        }
        webRtcEndpoint.on('OnIceCandidate', function (event) {
          var candidate = kurento.register.complexTypes.IceCandidate(event.candidate);
          ws.send(JSON.stringify({
            id: 'iceCandidate',
            candidate: candidate
          }));
        });

        webRtcEndpoint.processOffer(sdpOffer, function(error, sdpAnswer) {
          if (presenter === null) {
            stop(sessionId);
            console.log(8)
            return callback(noPresenterMessage);
          }

          webRtcEndpoint.gatherCandidates(function(error, result) {
            if (result) console.log(result);
            console.log("Gathering candidates...");
          });

          callback(null, sdpAnswer);

          presenter.pipeline.connect(webRtcEndpoint, webRtcEndpoint, recorder, function(error){
            if (error) {
              stop(sessionId);
              console.log(10)
              return onError(error);
            }

            recorder.record(function(error) {
              if (error) return onError(error);
            });

            console.log( recorder )
          });

          presenter.pipeline.connect(webRtcEndpoint, webRtcEndpoint, player, function(error){
            if (error) {
              stop(sessionId);
              console.log(10)
              return onError(error);
            }

            player.on('EndOfStream', function() {
              console.log('END OF STREAM');
            });

            player.play(function(error) {
              console.log('play or not play')
              if (error) return onError(error);
            });
          });
        });

      });

    });

  });
}