How to use the sdp.getIceParameters function in sdp

sections.forEach(function(mediaSection, sdpMLineIndex) {
              var transceiver = self.transceivers[sdpMLineIndex];
              var iceGatherer = transceiver.iceGatherer;
              var iceTransport = transceiver.iceTransport;
              var dtlsTransport = transceiver.dtlsTransport;
              var localCapabilities = transceiver.localCapabilities;
              var remoteCapabilities = transceiver.remoteCapabilities;

              var rejected = mediaSection.split('\n', 1)[0]
                  .split(' ', 2)[1] === '0';

              if (!rejected && !transceiver.isDatachannel) {
                var remoteIceParameters = SDPUtils.getIceParameters(
                    mediaSection, sessionpart);
                if (isIceLite) {
                  var cands = SDPUtils.matchPrefix(mediaSection, 'a=candidate:')
                  .map(function(cand) {
                    return SDPUtils.parseCandidate(cand);
                  })
                  .filter(function(cand) {
                    return cand.component === '1';
                  });
                  // ice-lite only includes host candidates in the SDP so we can
                  // use setRemoteCandidates (which implies an
                  // RTCIceCandidateComplete)
                  if (cands.length) {
                    iceTransport.setRemoteCandidates(cands);
                  }
                }

sections.forEach(function(mediaSection, sdpMLineIndex) {
              var transceiver = self.transceivers[sdpMLineIndex];
              var iceGatherer = transceiver.iceGatherer;
              var iceTransport = transceiver.iceTransport;
              var dtlsTransport = transceiver.dtlsTransport;
              var localCapabilities = transceiver.localCapabilities;
              var remoteCapabilities = transceiver.remoteCapabilities;

              var rejected = mediaSection.split('\n', 1)[0]
                  .split(' ', 2)[1] === '0';

              if (!rejected && !transceiver.isDatachannel) {
                var remoteIceParameters = SDPUtils.getIceParameters(
                    mediaSection, sessionpart);
                if (isIceLite) {
                  var cands = SDPUtils.matchPrefix(mediaSection, 'a=candidate:')
                  .map(function(cand) {
                    return SDPUtils.parseCandidate(cand);
                  })
                  .filter(function(cand) {
                    return cand.component === '1';
                  });
                  // ice-lite only includes host candidates in the SDP so we can
                  // use setRemoteCandidates (which implies an
                  // RTCIceCandidateComplete)
                  if (cands.length) {
                    iceTransport.setRemoteCandidates(cands);
                  }
                }

var transceiver;
      var iceGatherer;
      var iceTransport;
      var dtlsTransport;
      var rtpReceiver;
      var sendEncodingParameters;
      var recvEncodingParameters;
      var localCapabilities;

      var track;
      // FIXME: ensure the mediaSection has rtcp-mux set.
      var remoteCapabilities = SDPUtils.parseRtpParameters(mediaSection);
      var remoteIceParameters;
      var remoteDtlsParameters;
      if (!rejected) {
        remoteIceParameters = SDPUtils.getIceParameters(mediaSection,
            sessionpart);
        remoteDtlsParameters = SDPUtils.getDtlsParameters(mediaSection,
            sessionpart);
        remoteDtlsParameters.role = 'client';
      }
      recvEncodingParameters =
          SDPUtils.parseRtpEncodingParameters(mediaSection);

      var rtcpParameters = SDPUtils.parseRtcpParameters(mediaSection);

      var isComplete = SDPUtils.matchPrefix(mediaSection,
          'a=end-of-candidates', sessionpart).length > 0;
      var cands = SDPUtils.matchPrefix(mediaSection, 'a=candidate:')
          .map(function(cand) {
            return SDPUtils.parseCandidate(cand);
          })

var iceGatherer;
            var iceTransport;
            var dtlsTransport;
            var rtpSender;
            var rtpReceiver;
            var sendEncodingParameters;
            var recvEncodingParameters;
            var localCapabilities;

            var track;
            // FIXME: ensure the mediaSection has rtcp-mux set.
            var remoteCapabilities = SDPUtils.parseRtpParameters(mediaSection);
            var remoteIceParameters;
            var remoteDtlsParameters;
            if (!rejected) {
              remoteIceParameters = SDPUtils.getIceParameters(mediaSection,
                  sessionpart);
              remoteDtlsParameters = SDPUtils.getDtlsParameters(mediaSection,
                  sessionpart);
              remoteDtlsParameters.role = 'client';
            }
            recvEncodingParameters =
                SDPUtils.parseRtpEncodingParameters(mediaSection);

            var cname;
            // Gets the first SSRC. Note that with RTX there might be multiple
            // SSRCs.
            var remoteSsrc = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
                .map(function(line) {
                  return SDPUtils.parseSsrcMedia(line);
                })
                .filter(function(obj) {

var iceGatherer;
            var iceTransport;
            var dtlsTransport;
            var rtpSender;
            var rtpReceiver;
            var sendEncodingParameters;
            var recvEncodingParameters;
            var localCapabilities;

            var track;
            // FIXME: ensure the mediaSection has rtcp-mux set.
            var remoteCapabilities = SDPUtils.parseRtpParameters(mediaSection);
            var remoteIceParameters;
            var remoteDtlsParameters;
            if (!rejected) {
              remoteIceParameters = SDPUtils.getIceParameters(mediaSection,
                  sessionpart);
              remoteDtlsParameters = SDPUtils.getDtlsParameters(mediaSection,
                  sessionpart);
              remoteDtlsParameters.role = 'client';
            }
            recvEncodingParameters =
                SDPUtils.parseRtpEncodingParameters(mediaSection);

            var mid = SDPUtils.matchPrefix(mediaSection, 'a=mid:');
            if (mid.length) {
              mid = mid[0].substr(6);
            } else {
              mid = SDPUtils.generateIdentifier();
            }

            var cname;

sections.forEach(function(mediaSection, sdpMLineIndex) {
        var transceiver = self.transceivers[sdpMLineIndex];
        var iceGatherer = transceiver.iceGatherer;
        var iceTransport = transceiver.iceTransport;
        var dtlsTransport = transceiver.dtlsTransport;
        var localCapabilities = transceiver.localCapabilities;
        var remoteCapabilities = transceiver.remoteCapabilities;

        var rejected = SDPUtils.isRejected(mediaSection);

        if (!rejected && !transceiver.isDatachannel) {
          var remoteIceParameters = SDPUtils.getIceParameters(
              mediaSection, sessionpart);
          var remoteDtlsParameters = SDPUtils.getDtlsParameters(
              mediaSection, sessionpart);
          if (isIceLite) {
            remoteDtlsParameters.role = 'server';
          }

          if (!self.usingBundle || sdpMLineIndex === 0) {
            iceTransport.start(iceGatherer, remoteIceParameters,
                isIceLite ? 'controlling' : 'controlled');
            dtlsTransport.start(remoteDtlsParameters);
          }

          // Calculate intersection of capabilities.
          var params = getCommonCapabilities(localCapabilities,
              remoteCapabilities);

var iceGatherer;
            var iceTransport;
            var dtlsTransport;
            var rtpSender;
            var rtpReceiver;
            var sendEncodingParameters;
            var recvEncodingParameters;
            var localCapabilities;

            var track;
            // FIXME: ensure the mediaSection has rtcp-mux set.
            var remoteCapabilities = SDPUtils.parseRtpParameters(mediaSection);
            var remoteIceParameters;
            var remoteDtlsParameters;
            if (!rejected) {
              remoteIceParameters = SDPUtils.getIceParameters(mediaSection,
                  sessionpart);
              remoteDtlsParameters = SDPUtils.getDtlsParameters(mediaSection,
                  sessionpart);
              remoteDtlsParameters.role = 'client';
            }
            recvEncodingParameters =
                SDPUtils.parseRtpEncodingParameters(mediaSection);

            var cname;
            // Gets the first SSRC. Note that with RTX there might be multiple
            // SSRCs.
            var remoteSsrc = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
                .map(function(line) {
                  return SDPUtils.parseSsrcMedia(line);
                })
                .filter(function(obj) {

function mergeSimulcast(sdp) {
	const sections = SDPUtils.splitSections(sdp);
    const candidates = SDPUtils.matchPrefix(sections[1], 'a=candidate:');
    const dtls = SDPUtils.getDtlsParameters(sections[1], sections[0]);
    const ice = SDPUtils.getIceParameters(sections[1], sections[0]);
    const rtpParameters = SDPUtils.parseRtpParameters(sections[1]);
    sdp = 'v=0\r\n' +
      'o=mozilla...THIS_IS_SDPARTA-61.0 8324701712193024513 0 IN IP4 0.0.0.0\r\n' +
      's=-\r\n' +
      't=0 0\r\n' +
      'a=fingerprint:' + dtls.fingerprints[0].algorithm + ' ' + dtls.fingerprints[0].value + '\r\n' +
      'a=ice-ufrag:' + ice.usernameFragment + '\r\n' +
      'a=ice-pwd:' + ice.password + '\r\n' +
      'a=group:BUNDLE 0\r\n' +
      'a=msid-semantic:WMS *\r\n';
    const codecs = SDPUtils.writeRtpDescription('video', rtpParameters);
    sdp += codecs;
    candidates.forEach(c => sdp += c + '\r\n');
    return sdp;
}