restructured stuff
authorjordan lavatai <jordanlavatai@gmail.com>
Wed, 21 Jun 2017 23:35:39 +0000 (16:35 -0700)
committerjordan lavatai <jordanlavatai@gmail.com>
Wed, 21 Jun 2017 23:35:39 +0000 (16:35 -0700)
adapter.js [new file with mode: 0644]
admin.js [deleted file]
client/client.html [moved from admin.css with 100% similarity]
client/client.js [new file with mode: 0644]
host/host.html [moved from admin.html with 100% similarity]
host/host.js [new file with mode: 0644]
main.js
package.json
renderer.html [deleted file]
renderer.js [deleted file]

diff --git a/adapter.js b/adapter.js
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+(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.adapter = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
+ /* eslint-env node */
+'use strict';
+
+// SDP helpers.
+var SDPUtils = {};
+
+// Generate an alphanumeric identifier for cname or mids.
+// TODO: use UUIDs instead? https://gist.github.com/jed/982883
+SDPUtils.generateIdentifier = function() {
+  return Math.random().toString(36).substr(2, 10);
+};
+
+// The RTCP CNAME used by all peerconnections from the same JS.
+SDPUtils.localCName = SDPUtils.generateIdentifier();
+
+// Splits SDP into lines, dealing with both CRLF and LF.
+SDPUtils.splitLines = function(blob) {
+  return blob.trim().split('\n').map(function(line) {
+    return line.trim();
+  });
+};
+// Splits SDP into sessionpart and mediasections. Ensures CRLF.
+SDPUtils.splitSections = function(blob) {
+  var parts = blob.split('\nm=');
+  return parts.map(function(part, index) {
+    return (index > 0 ? 'm=' + part : part).trim() + '\r\n';
+  });
+};
+
+// Returns lines that start with a certain prefix.
+SDPUtils.matchPrefix = function(blob, prefix) {
+  return SDPUtils.splitLines(blob).filter(function(line) {
+    return line.indexOf(prefix) === 0;
+  });
+};
+
+// Parses an ICE candidate line. Sample input:
+// candidate:702786350 2 udp 41819902 8.8.8.8 60769 typ relay raddr 8.8.8.8
+// rport 55996"
+SDPUtils.parseCandidate = function(line) {
+  var parts;
+  // Parse both variants.
+  if (line.indexOf('a=candidate:') === 0) {
+    parts = line.substring(12).split(' ');
+  } else {
+    parts = line.substring(10).split(' ');
+  }
+
+  var candidate = {
+    foundation: parts[0],
+    component: parseInt(parts[1], 10),
+    protocol: parts[2].toLowerCase(),
+    priority: parseInt(parts[3], 10),
+    ip: parts[4],
+    port: parseInt(parts[5], 10),
+    // skip parts[6] == 'typ'
+    type: parts[7]
+  };
+
+  for (var i = 8; i < parts.length; i += 2) {
+    switch (parts[i]) {
+      case 'raddr':
+        candidate.relatedAddress = parts[i + 1];
+        break;
+      case 'rport':
+        candidate.relatedPort = parseInt(parts[i + 1], 10);
+        break;
+      case 'tcptype':
+        candidate.tcpType = parts[i + 1];
+        break;
+      default: // extension handling, in particular ufrag
+        candidate[parts[i]] = parts[i + 1];
+        break;
+    }
+  }
+  return candidate;
+};
+
+// Translates a candidate object into SDP candidate attribute.
+SDPUtils.writeCandidate = function(candidate) {
+  var sdp = [];
+  sdp.push(candidate.foundation);
+  sdp.push(candidate.component);
+  sdp.push(candidate.protocol.toUpperCase());
+  sdp.push(candidate.priority);
+  sdp.push(candidate.ip);
+  sdp.push(candidate.port);
+
+  var type = candidate.type;
+  sdp.push('typ');
+  sdp.push(type);
+  if (type !== 'host' && candidate.relatedAddress &&
+      candidate.relatedPort) {
+    sdp.push('raddr');
+    sdp.push(candidate.relatedAddress); // was: relAddr
+    sdp.push('rport');
+    sdp.push(candidate.relatedPort); // was: relPort
+  }
+  if (candidate.tcpType && candidate.protocol.toLowerCase() === 'tcp') {
+    sdp.push('tcptype');
+    sdp.push(candidate.tcpType);
+  }
+  if (candidate.ufrag) {
+    sdp.push('ufrag');
+    sdp.push(candidate.ufrag);
+  }
+  return 'candidate:' + sdp.join(' ');
+};
+
+// Parses an ice-options line, returns an array of option tags.
+// a=ice-options:foo bar
+SDPUtils.parseIceOptions = function(line) {
+  return line.substr(14).split(' ');
+}
+
+// Parses an rtpmap line, returns RTCRtpCoddecParameters. Sample input:
+// a=rtpmap:111 opus/48000/2
+SDPUtils.parseRtpMap = function(line) {
+  var parts = line.substr(9).split(' ');
+  var parsed = {
+    payloadType: parseInt(parts.shift(), 10) // was: id
+  };
+
+  parts = parts[0].split('/');
+
+  parsed.name = parts[0];
+  parsed.clockRate = parseInt(parts[1], 10); // was: clockrate
+  // was: channels
+  parsed.numChannels = parts.length === 3 ? parseInt(parts[2], 10) : 1;
+  return parsed;
+};
+
+// Generate an a=rtpmap line from RTCRtpCodecCapability or
+// RTCRtpCodecParameters.
+SDPUtils.writeRtpMap = function(codec) {
+  var pt = codec.payloadType;
+  if (codec.preferredPayloadType !== undefined) {
+    pt = codec.preferredPayloadType;
+  }
+  return 'a=rtpmap:' + pt + ' ' + codec.name + '/' + codec.clockRate +
+      (codec.numChannels !== 1 ? '/' + codec.numChannels : '') + '\r\n';
+};
+
+// Parses an a=extmap line (headerextension from RFC 5285). Sample input:
+// a=extmap:2 urn:ietf:params:rtp-hdrext:toffset
+// a=extmap:2/sendonly urn:ietf:params:rtp-hdrext:toffset
+SDPUtils.parseExtmap = function(line) {
+  var parts = line.substr(9).split(' ');
+  return {
+    id: parseInt(parts[0], 10),
+    direction: parts[0].indexOf('/') > 0 ? parts[0].split('/')[1] : 'sendrecv',
+    uri: parts[1]
+  };
+};
+
+// Generates a=extmap line from RTCRtpHeaderExtensionParameters or
+// RTCRtpHeaderExtension.
+SDPUtils.writeExtmap = function(headerExtension) {
+  return 'a=extmap:' + (headerExtension.id || headerExtension.preferredId) +
+      (headerExtension.direction && headerExtension.direction !== 'sendrecv'
+          ? '/' + headerExtension.direction
+          : '') +
+      ' ' + headerExtension.uri + '\r\n';
+};
+
+// Parses an ftmp line, returns dictionary. Sample input:
+// a=fmtp:96 vbr=on;cng=on
+// Also deals with vbr=on; cng=on
+SDPUtils.parseFmtp = function(line) {
+  var parsed = {};
+  var kv;
+  var parts = line.substr(line.indexOf(' ') + 1).split(';');
+  for (var j = 0; j < parts.length; j++) {
+    kv = parts[j].trim().split('=');
+    parsed[kv[0].trim()] = kv[1];
+  }
+  return parsed;
+};
+
+// Generates an a=ftmp line from RTCRtpCodecCapability or RTCRtpCodecParameters.
+SDPUtils.writeFmtp = function(codec) {
+  var line = '';
+  var pt = codec.payloadType;
+  if (codec.preferredPayloadType !== undefined) {
+    pt = codec.preferredPayloadType;
+  }
+  if (codec.parameters && Object.keys(codec.parameters).length) {
+    var params = [];
+    Object.keys(codec.parameters).forEach(function(param) {
+      params.push(param + '=' + codec.parameters[param]);
+    });
+    line += 'a=fmtp:' + pt + ' ' + params.join(';') + '\r\n';
+  }
+  return line;
+};
+
+// Parses an rtcp-fb line, returns RTCPRtcpFeedback object. Sample input:
+// a=rtcp-fb:98 nack rpsi
+SDPUtils.parseRtcpFb = function(line) {
+  var parts = line.substr(line.indexOf(' ') + 1).split(' ');
+  return {
+    type: parts.shift(),
+    parameter: parts.join(' ')
+  };
+};
+// Generate a=rtcp-fb lines from RTCRtpCodecCapability or RTCRtpCodecParameters.
+SDPUtils.writeRtcpFb = function(codec) {
+  var lines = '';
+  var pt = codec.payloadType;
+  if (codec.preferredPayloadType !== undefined) {
+    pt = codec.preferredPayloadType;
+  }
+  if (codec.rtcpFeedback && codec.rtcpFeedback.length) {
+    // FIXME: special handling for trr-int?
+    codec.rtcpFeedback.forEach(function(fb) {
+      lines += 'a=rtcp-fb:' + pt + ' ' + fb.type +
+      (fb.parameter && fb.parameter.length ? ' ' + fb.parameter : '') +
+          '\r\n';
+    });
+  }
+  return lines;
+};
+
+// Parses an RFC 5576 ssrc media attribute. Sample input:
+// a=ssrc:3735928559 cname:something
+SDPUtils.parseSsrcMedia = function(line) {
+  var sp = line.indexOf(' ');
+  var parts = {
+    ssrc: parseInt(line.substr(7, sp - 7), 10)
+  };
+  var colon = line.indexOf(':', sp);
+  if (colon > -1) {
+    parts.attribute = line.substr(sp + 1, colon - sp - 1);
+    parts.value = line.substr(colon + 1);
+  } else {
+    parts.attribute = line.substr(sp + 1);
+  }
+  return parts;
+};
+
+// Extracts the MID (RFC 5888) from a media section.
+// returns the MID or undefined if no mid line was found.
+SDPUtils.getMid = function(mediaSection) {
+  var mid = SDPUtils.matchPrefix(mediaSection, 'a=mid:')[0];
+  if (mid) {
+    return mid.substr(6);
+  }
+}
+
+SDPUtils.parseFingerprint = function(line) {
+  var parts = line.substr(14).split(' ');
+  return {
+    algorithm: parts[0].toLowerCase(), // algorithm is case-sensitive in Edge.
+    value: parts[1]
+  };
+};
+
+// Extracts DTLS parameters from SDP media section or sessionpart.
+// FIXME: for consistency with other functions this should only
+//   get the fingerprint line as input. See also getIceParameters.
+SDPUtils.getDtlsParameters = function(mediaSection, sessionpart) {
+  var lines = SDPUtils.matchPrefix(mediaSection + sessionpart,
+      'a=fingerprint:');
+  // Note: a=setup line is ignored since we use the 'auto' role.
+  // Note2: 'algorithm' is not case sensitive except in Edge.
+  return {
+    role: 'auto',
+    fingerprints: lines.map(SDPUtils.parseFingerprint)
+  };
+};
+
+// Serializes DTLS parameters to SDP.
+SDPUtils.writeDtlsParameters = function(params, setupType) {
+  var sdp = 'a=setup:' + setupType + '\r\n';
+  params.fingerprints.forEach(function(fp) {
+    sdp += 'a=fingerprint:' + fp.algorithm + ' ' + fp.value + '\r\n';
+  });
+  return sdp;
+};
+// Parses ICE information from SDP media section or sessionpart.
+// FIXME: for consistency with other functions this should only
+//   get the ice-ufrag and ice-pwd lines as input.
+SDPUtils.getIceParameters = function(mediaSection, sessionpart) {
+  var lines = SDPUtils.splitLines(mediaSection);
+  // Search in session part, too.
+  lines = lines.concat(SDPUtils.splitLines(sessionpart));
+  var iceParameters = {
+    usernameFragment: lines.filter(function(line) {
+      return line.indexOf('a=ice-ufrag:') === 0;
+    })[0].substr(12),
+    password: lines.filter(function(line) {
+      return line.indexOf('a=ice-pwd:') === 0;
+    })[0].substr(10)
+  };
+  return iceParameters;
+};
+
+// Serializes ICE parameters to SDP.
+SDPUtils.writeIceParameters = function(params) {
+  return 'a=ice-ufrag:' + params.usernameFragment + '\r\n' +
+      'a=ice-pwd:' + params.password + '\r\n';
+};
+
+// Parses the SDP media section and returns RTCRtpParameters.
+SDPUtils.parseRtpParameters = function(mediaSection) {
+  var description = {
+    codecs: [],
+    headerExtensions: [],
+    fecMechanisms: [],
+    rtcp: []
+  };
+  var lines = SDPUtils.splitLines(mediaSection);
+  var mline = lines[0].split(' ');
+  for (var i = 3; i < mline.length; i++) { // find all codecs from mline[3..]
+    var pt = mline[i];
+    var rtpmapline = SDPUtils.matchPrefix(
+        mediaSection, 'a=rtpmap:' + pt + ' ')[0];
+    if (rtpmapline) {
+      var codec = SDPUtils.parseRtpMap(rtpmapline);
+      var fmtps = SDPUtils.matchPrefix(
+          mediaSection, 'a=fmtp:' + pt + ' ');
+      // Only the first a=fmtp:<pt> is considered.
+      codec.parameters = fmtps.length ? SDPUtils.parseFmtp(fmtps[0]) : {};
+      codec.rtcpFeedback = SDPUtils.matchPrefix(
+          mediaSection, 'a=rtcp-fb:' + pt + ' ')
+        .map(SDPUtils.parseRtcpFb);
+      description.codecs.push(codec);
+      // parse FEC mechanisms from rtpmap lines.
+      switch (codec.name.toUpperCase()) {
+        case 'RED':
+        case 'ULPFEC':
+          description.fecMechanisms.push(codec.name.toUpperCase());
+          break;
+        default: // only RED and ULPFEC are recognized as FEC mechanisms.
+          break;
+      }
+    }
+  }
+  SDPUtils.matchPrefix(mediaSection, 'a=extmap:').forEach(function(line) {
+    description.headerExtensions.push(SDPUtils.parseExtmap(line));
+  });
+  // FIXME: parse rtcp.
+  return description;
+};
+
+// Generates parts of the SDP media section describing the capabilities /
+// parameters.
+SDPUtils.writeRtpDescription = function(kind, caps) {
+  var sdp = '';
+
+  // Build the mline.
+  sdp += 'm=' + kind + ' ';
+  sdp += caps.codecs.length > 0 ? '9' : '0'; // reject if no codecs.
+  sdp += ' UDP/TLS/RTP/SAVPF ';
+  sdp += caps.codecs.map(function(codec) {
+    if (codec.preferredPayloadType !== undefined) {
+      return codec.preferredPayloadType;
+    }
+    return codec.payloadType;
+  }).join(' ') + '\r\n';
+
+  sdp += 'c=IN IP4 0.0.0.0\r\n';
+  sdp += 'a=rtcp:9 IN IP4 0.0.0.0\r\n';
+
+  // Add a=rtpmap lines for each codec. Also fmtp and rtcp-fb.
+  caps.codecs.forEach(function(codec) {
+    sdp += SDPUtils.writeRtpMap(codec);
+    sdp += SDPUtils.writeFmtp(codec);
+    sdp += SDPUtils.writeRtcpFb(codec);
+  });
+  var maxptime = 0;
+  caps.codecs.forEach(function(codec) {
+    if (codec.maxptime > maxptime) {
+      maxptime = codec.maxptime;
+    }
+  });
+  if (maxptime > 0) {
+    sdp += 'a=maxptime:' + maxptime + '\r\n';
+  }
+  sdp += 'a=rtcp-mux\r\n';
+
+  caps.headerExtensions.forEach(function(extension) {
+    sdp += SDPUtils.writeExtmap(extension);
+  });
+  // FIXME: write fecMechanisms.
+  return sdp;
+};
+
+// Parses the SDP media section and returns an array of
+// RTCRtpEncodingParameters.
+SDPUtils.parseRtpEncodingParameters = function(mediaSection) {
+  var encodingParameters = [];
+  var description = SDPUtils.parseRtpParameters(mediaSection);
+  var hasRed = description.fecMechanisms.indexOf('RED') !== -1;
+  var hasUlpfec = description.fecMechanisms.indexOf('ULPFEC') !== -1;
+
+  // filter a=ssrc:... cname:, ignore PlanB-msid
+  var ssrcs = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
+  .map(function(line) {
+    return SDPUtils.parseSsrcMedia(line);
+  })
+  .filter(function(parts) {
+    return parts.attribute === 'cname';
+  });
+  var primarySsrc = ssrcs.length > 0 && ssrcs[0].ssrc;
+  var secondarySsrc;
+
+  var flows = SDPUtils.matchPrefix(mediaSection, 'a=ssrc-group:FID')
+  .map(function(line) {
+    var parts = line.split(' ');
+    parts.shift();
+    return parts.map(function(part) {
+      return parseInt(part, 10);
+    });
+  });
+  if (flows.length > 0 && flows[0].length > 1 && flows[0][0] === primarySsrc) {
+    secondarySsrc = flows[0][1];
+  }
+
+  description.codecs.forEach(function(codec) {
+    if (codec.name.toUpperCase() === 'RTX' && codec.parameters.apt) {
+      var encParam = {
+        ssrc: primarySsrc,
+        codecPayloadType: parseInt(codec.parameters.apt, 10),
+        rtx: {
+          ssrc: secondarySsrc
+        }
+      };
+      encodingParameters.push(encParam);
+      if (hasRed) {
+        encParam = JSON.parse(JSON.stringify(encParam));
+        encParam.fec = {
+          ssrc: secondarySsrc,
+          mechanism: hasUlpfec ? 'red+ulpfec' : 'red'
+        };
+        encodingParameters.push(encParam);
+      }
+    }
+  });
+  if (encodingParameters.length === 0 && primarySsrc) {
+    encodingParameters.push({
+      ssrc: primarySsrc
+    });
+  }
+
+  // we support both b=AS and b=TIAS but interpret AS as TIAS.
+  var bandwidth = SDPUtils.matchPrefix(mediaSection, 'b=');
+  if (bandwidth.length) {
+    if (bandwidth[0].indexOf('b=TIAS:') === 0) {
+      bandwidth = parseInt(bandwidth[0].substr(7), 10);
+    } else if (bandwidth[0].indexOf('b=AS:') === 0) {
+      // use formula from JSEP to convert b=AS to TIAS value.
+      bandwidth = parseInt(bandwidth[0].substr(5), 10) * 1000 * 0.95
+          - (50 * 40 * 8);
+    } else {
+      bandwidth = undefined;
+    }
+    encodingParameters.forEach(function(params) {
+      params.maxBitrate = bandwidth;
+    });
+  }
+  return encodingParameters;
+};
+
+// parses http://draft.ortc.org/#rtcrtcpparameters*
+SDPUtils.parseRtcpParameters = function(mediaSection) {
+  var rtcpParameters = {};
+
+  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) {
+        return obj.attribute === 'cname';
+      })[0];
+  if (remoteSsrc) {
+    rtcpParameters.cname = remoteSsrc.value;
+    rtcpParameters.ssrc = remoteSsrc.ssrc;
+  }
+
+  // Edge uses the compound attribute instead of reducedSize
+  // compound is !reducedSize
+  var rsize = SDPUtils.matchPrefix(mediaSection, 'a=rtcp-rsize');
+  rtcpParameters.reducedSize = rsize.length > 0;
+  rtcpParameters.compound = rsize.length === 0;
+
+  // parses the rtcp-mux attrŅ–bute.
+  // Note that Edge does not support unmuxed RTCP.
+  var mux = SDPUtils.matchPrefix(mediaSection, 'a=rtcp-mux');
+  rtcpParameters.mux = mux.length > 0;
+
+  return rtcpParameters;
+};
+
+// parses either a=msid: or a=ssrc:... msid lines and returns
+// the id of the MediaStream and MediaStreamTrack.
+SDPUtils.parseMsid = function(mediaSection) {
+  var parts;
+  var spec = SDPUtils.matchPrefix(mediaSection, 'a=msid:');
+  if (spec.length === 1) {
+    parts = spec[0].substr(7).split(' ');
+    return {stream: parts[0], track: parts[1]};
+  }
+  var planB = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
+  .map(function(line) {
+    return SDPUtils.parseSsrcMedia(line);
+  })
+  .filter(function(parts) {
+    return parts.attribute === 'msid';
+  });
+  if (planB.length > 0) {
+    parts = planB[0].value.split(' ');
+    return {stream: parts[0], track: parts[1]};
+  }
+};
+
+// Generate a session ID for SDP.
+// https://tools.ietf.org/html/draft-ietf-rtcweb-jsep-20#section-5.2.1
+// recommends using a cryptographically random +ve 64-bit value
+// but right now this should be acceptable and within the right range
+SDPUtils.generateSessionId = function() {
+  return Math.random().toString().substr(2, 21);
+};
+
+// Write boilder plate for start of SDP
+// sessId argument is optional - if not supplied it will
+// be generated randomly
+SDPUtils.writeSessionBoilerplate = function(sessId) {
+  var sessionId;
+  if (sessId) {
+    sessionId = sessId;
+  } else {
+    sessionId = SDPUtils.generateSessionId();
+  }
+  // FIXME: sess-id should be an NTP timestamp.
+  return 'v=0\r\n' +
+      'o=thisisadapterortc ' + sessionId + ' 2 IN IP4 127.0.0.1\r\n' +
+      's=-\r\n' +
+      't=0 0\r\n';
+};
+
+SDPUtils.writeMediaSection = function(transceiver, caps, type, stream) {
+  var sdp = SDPUtils.writeRtpDescription(transceiver.kind, caps);
+
+  // Map ICE parameters (ufrag, pwd) to SDP.
+  sdp += SDPUtils.writeIceParameters(
+      transceiver.iceGatherer.getLocalParameters());
+
+  // Map DTLS parameters to SDP.
+  sdp += SDPUtils.writeDtlsParameters(
+      transceiver.dtlsTransport.getLocalParameters(),
+      type === 'offer' ? 'actpass' : 'active');
+
+  sdp += 'a=mid:' + transceiver.mid + '\r\n';
+
+  if (transceiver.direction) {
+    sdp += 'a=' + transceiver.direction + '\r\n';
+  } else if (transceiver.rtpSender && transceiver.rtpReceiver) {
+    sdp += 'a=sendrecv\r\n';
+  } else if (transceiver.rtpSender) {
+    sdp += 'a=sendonly\r\n';
+  } else if (transceiver.rtpReceiver) {
+    sdp += 'a=recvonly\r\n';
+  } else {
+    sdp += 'a=inactive\r\n';
+  }
+
+  if (transceiver.rtpSender) {
+    // spec.
+    var msid = 'msid:' + stream.id + ' ' +
+        transceiver.rtpSender.track.id + '\r\n';
+    sdp += 'a=' + msid;
+
+    // for Chrome.
+    sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].ssrc +
+        ' ' + msid;
+    if (transceiver.sendEncodingParameters[0].rtx) {
+      sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].rtx.ssrc +
+          ' ' + msid;
+      sdp += 'a=ssrc-group:FID ' +
+          transceiver.sendEncodingParameters[0].ssrc + ' ' +
+          transceiver.sendEncodingParameters[0].rtx.ssrc +
+          '\r\n';
+    }
+  }
+  // FIXME: this should be written by writeRtpDescription.
+  sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].ssrc +
+      ' cname:' + SDPUtils.localCName + '\r\n';
+  if (transceiver.rtpSender && transceiver.sendEncodingParameters[0].rtx) {
+    sdp += 'a=ssrc:' + transceiver.sendEncodingParameters[0].rtx.ssrc +
+        ' cname:' + SDPUtils.localCName + '\r\n';
+  }
+  return sdp;
+};
+
+// Gets the direction from the mediaSection or the sessionpart.
+SDPUtils.getDirection = function(mediaSection, sessionpart) {
+  // Look for sendrecv, sendonly, recvonly, inactive, default to sendrecv.
+  var lines = SDPUtils.splitLines(mediaSection);
+  for (var i = 0; i < lines.length; i++) {
+    switch (lines[i]) {
+      case 'a=sendrecv':
+      case 'a=sendonly':
+      case 'a=recvonly':
+      case 'a=inactive':
+        return lines[i].substr(2);
+      default:
+        // FIXME: What should happen here?
+    }
+  }
+  if (sessionpart) {
+    return SDPUtils.getDirection(sessionpart);
+  }
+  return 'sendrecv';
+};
+
+SDPUtils.getKind = function(mediaSection) {
+  var lines = SDPUtils.splitLines(mediaSection);
+  var mline = lines[0].split(' ');
+  return mline[0].substr(2);
+};
+
+SDPUtils.isRejected = function(mediaSection) {
+  return mediaSection.split(' ', 2)[1] === '0';
+};
+
+// Expose public methods.
+module.exports = SDPUtils;
+
+},{}],2:[function(require,module,exports){
+(function (global){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+
+'use strict';
+
+var adapterFactory = require('./adapter_factory.js');
+module.exports = adapterFactory({window: global.window});
+
+}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
+},{"./adapter_factory.js":3}],3:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+
+'use strict';
+
+// Shimming starts here.
+module.exports = function(dependencies) {
+  var window = dependencies && dependencies.window;
+
+  // Utils.
+  var utils = require('./utils');
+  var logging = utils.log;
+  var browserDetails = utils.detectBrowser(window);
+
+  // Export to the adapter global object visible in the browser.
+  var adapter = {
+    browserDetails: browserDetails,
+    extractVersion: utils.extractVersion,
+    disableLog: utils.disableLog,
+    disableWarnings: utils.disableWarnings
+  };
+
+  // Uncomment the line below if you want logging to occur, including logging
+  // for the switch statement below. Can also be turned on in the browser via
+  // adapter.disableLog(false), but then logging from the switch statement below
+  // will not appear.
+  // require('./utils').disableLog(false);
+
+  // Browser shims.
+  var chromeShim = require('./chrome/chrome_shim') || null;
+  var edgeShim = require('./edge/edge_shim') || null;
+  var firefoxShim = require('./firefox/firefox_shim') || null;
+  var safariShim = require('./safari/safari_shim') || null;
+
+  // Shim browser if found.
+  switch (browserDetails.browser) {
+    case 'chrome':
+      if (!chromeShim || !chromeShim.shimPeerConnection) {
+        logging('Chrome shim is not included in this adapter release.');
+        return adapter;
+      }
+      logging('adapter.js shimming chrome.');
+      // Export to the adapter global object visible in the browser.
+      adapter.browserShim = chromeShim;
+
+      chromeShim.shimGetUserMedia(window);
+      chromeShim.shimMediaStream(window);
+      utils.shimCreateObjectURL(window);
+      chromeShim.shimSourceObject(window);
+      chromeShim.shimPeerConnection(window);
+      chromeShim.shimOnTrack(window);
+      chromeShim.shimGetSendersWithDtmf(window);
+      break;
+    case 'firefox':
+      if (!firefoxShim || !firefoxShim.shimPeerConnection) {
+        logging('Firefox shim is not included in this adapter release.');
+        return adapter;
+      }
+      logging('adapter.js shimming firefox.');
+      // Export to the adapter global object visible in the browser.
+      adapter.browserShim = firefoxShim;
+
+      firefoxShim.shimGetUserMedia(window);
+      utils.shimCreateObjectURL(window);
+      firefoxShim.shimSourceObject(window);
+      firefoxShim.shimPeerConnection(window);
+      firefoxShim.shimOnTrack(window);
+      break;
+    case 'edge':
+      if (!edgeShim || !edgeShim.shimPeerConnection) {
+        logging('MS edge shim is not included in this adapter release.');
+        return adapter;
+      }
+      logging('adapter.js shimming edge.');
+      // Export to the adapter global object visible in the browser.
+      adapter.browserShim = edgeShim;
+
+      edgeShim.shimGetUserMedia(window);
+      utils.shimCreateObjectURL(window);
+      edgeShim.shimPeerConnection(window);
+      edgeShim.shimReplaceTrack(window);
+      break;
+    case 'safari':
+      if (!safariShim) {
+        logging('Safari shim is not included in this adapter release.');
+        return adapter;
+      }
+      logging('adapter.js shimming safari.');
+      // Export to the adapter global object visible in the browser.
+      adapter.browserShim = safariShim;
+      // shim window.URL.createObjectURL Safari (technical preview)
+      utils.shimCreateObjectURL(window);
+      safariShim.shimRTCIceServerUrls(window);
+      safariShim.shimCallbacksAPI(window);
+      safariShim.shimLocalStreamsAPI(window);
+      safariShim.shimRemoteStreamsAPI(window);
+      safariShim.shimGetUserMedia(window);
+      break;
+    default:
+      logging('Unsupported browser!');
+      break;
+  }
+
+  return adapter;
+};
+
+},{"./chrome/chrome_shim":4,"./edge/edge_shim":6,"./firefox/firefox_shim":9,"./safari/safari_shim":11,"./utils":12}],4:[function(require,module,exports){
+
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+var utils = require('../utils.js');
+var logging = utils.log;
+
+var chromeShim = {
+  shimMediaStream: function(window) {
+    window.MediaStream = window.MediaStream || window.webkitMediaStream;
+  },
+
+  shimOnTrack: function(window) {
+    if (typeof window === 'object' && window.RTCPeerConnection && !('ontrack' in
+        window.RTCPeerConnection.prototype)) {
+      Object.defineProperty(window.RTCPeerConnection.prototype, 'ontrack', {
+        get: function() {
+          return this._ontrack;
+        },
+        set: function(f) {
+          var self = this;
+          if (this._ontrack) {
+            this.removeEventListener('track', this._ontrack);
+            this.removeEventListener('addstream', this._ontrackpoly);
+          }
+          this.addEventListener('track', this._ontrack = f);
+          this.addEventListener('addstream', this._ontrackpoly = function(e) {
+            // onaddstream does not fire when a track is added to an existing
+            // stream. But stream.onaddtrack is implemented so we use that.
+            e.stream.addEventListener('addtrack', function(te) {
+              var receiver;
+              if (window.RTCPeerConnection.prototype.getReceivers) {
+                receiver = self.getReceivers().find(function(r) {
+                  return r.track.id === te.track.id;
+                });
+              } else {
+                receiver = {track: te.track};
+              }
+
+              var event = new Event('track');
+              event.track = te.track;
+              event.receiver = receiver;
+              event.streams = [e.stream];
+              self.dispatchEvent(event);
+            });
+            e.stream.getTracks().forEach(function(track) {
+              var receiver;
+              if (window.RTCPeerConnection.prototype.getReceivers) {
+                receiver = self.getReceivers().find(function(r) {
+                  return r.track.id === track.id;
+                });
+              } else {
+                receiver = {track: track};
+              }
+              var event = new Event('track');
+              event.track = track;
+              event.receiver = receiver;
+              event.streams = [e.stream];
+              this.dispatchEvent(event);
+            }.bind(this));
+          }.bind(this));
+        }
+      });
+    }
+  },
+
+  shimGetSendersWithDtmf: function(window) {
+    if (typeof window === 'object' && window.RTCPeerConnection &&
+        !('getSenders' in window.RTCPeerConnection.prototype) &&
+        'createDTMFSender' in window.RTCPeerConnection.prototype) {
+      window.RTCPeerConnection.prototype.getSenders = function() {
+        return this._senders || [];
+      };
+      var origAddStream = window.RTCPeerConnection.prototype.addStream;
+      var origRemoveStream = window.RTCPeerConnection.prototype.removeStream;
+
+      if (!window.RTCPeerConnection.prototype.addTrack) {
+        window.RTCPeerConnection.prototype.addTrack = function(track, stream) {
+          var pc = this;
+          if (pc.signalingState === 'closed') {
+            throw new DOMException(
+              'The RTCPeerConnection\'s signalingState is \'closed\'.',
+              'InvalidStateError');
+          }
+          var streams = [].slice.call(arguments, 1);
+          if (streams.length !== 1 ||
+              !streams[0].getTracks().find(function(t) {
+                return t === track;
+              })) {
+            // this is not fully correct but all we can manage without
+            // [[associated MediaStreams]] internal slot.
+            throw new DOMException(
+              'The adapter.js addTrack polyfill only supports a single ' +
+              ' stream which is associated with the specified track.',
+              'NotSupportedError');
+          }
+
+          pc._senders = pc._senders || [];
+          var alreadyExists = pc._senders.find(function(t) {
+            return t.track === track;
+          });
+          if (alreadyExists) {
+            throw new DOMException('Track already exists.',
+                'InvalidAccessError');
+          }
+
+          pc._streams = pc._streams || {};
+          var oldStream = pc._streams[stream.id];
+          if (oldStream) {
+            oldStream.addTrack(track);
+            pc.removeStream(oldStream);
+            pc.addStream(oldStream);
+          } else {
+            var newStream = new window.MediaStream([track]);
+            pc._streams[stream.id] = newStream;
+            pc.addStream(newStream);
+          }
+
+          var sender = {
+            track: track,
+            get dtmf() {
+              if (this._dtmf === undefined) {
+                if (track.kind === 'audio') {
+                  this._dtmf = pc.createDTMFSender(track);
+                } else {
+                  this._dtmf = null;
+                }
+              }
+              return this._dtmf;
+            }
+          };
+          pc._senders.push(sender);
+          return sender;
+        };
+      }
+      window.RTCPeerConnection.prototype.addStream = function(stream) {
+        var pc = this;
+        pc._senders = pc._senders || [];
+        origAddStream.apply(pc, [stream]);
+        stream.getTracks().forEach(function(track) {
+          pc._senders.push({
+            track: track,
+            get dtmf() {
+              if (this._dtmf === undefined) {
+                if (track.kind === 'audio') {
+                  this._dtmf = pc.createDTMFSender(track);
+                } else {
+                  this._dtmf = null;
+                }
+              }
+              return this._dtmf;
+            }
+          });
+        });
+      };
+
+      window.RTCPeerConnection.prototype.removeStream = function(stream) {
+        var pc = this;
+        pc._senders = pc._senders || [];
+        origRemoveStream.apply(pc, [stream]);
+        stream.getTracks().forEach(function(track) {
+          var sender = pc._senders.find(function(s) {
+            return s.track === track;
+          });
+          if (sender) {
+            pc._senders.splice(pc._senders.indexOf(sender), 1); // remove sender
+          }
+        });
+      };
+    } else if (typeof window === 'object' && window.RTCPeerConnection &&
+               'getSenders' in window.RTCPeerConnection.prototype &&
+               'createDTMFSender' in window.RTCPeerConnection.prototype &&
+               window.RTCRtpSender &&
+               !('dtmf' in window.RTCRtpSender.prototype)) {
+      var origGetSenders = window.RTCPeerConnection.prototype.getSenders;
+      window.RTCPeerConnection.prototype.getSenders = function() {
+        var pc = this;
+        var senders = origGetSenders.apply(pc, []);
+        senders.forEach(function(sender) {
+          sender._pc = pc;
+        });
+        return senders;
+      };
+
+      Object.defineProperty(window.RTCRtpSender.prototype, 'dtmf', {
+        get: function() {
+          if (this._dtmf === undefined) {
+            if (this.track.kind === 'audio') {
+              this._dtmf = this._pc.createDTMFSender(this.track);
+            } else {
+              this._dtmf = null;
+            }
+          }
+          return this._dtmf;
+        },
+      });
+    }
+  },
+
+  shimSourceObject: function(window) {
+    var URL = window && window.URL;
+
+    if (typeof window === 'object') {
+      if (window.HTMLMediaElement &&
+        !('srcObject' in window.HTMLMediaElement.prototype)) {
+        // Shim the srcObject property, once, when HTMLMediaElement is found.
+        Object.defineProperty(window.HTMLMediaElement.prototype, 'srcObject', {
+          get: function() {
+            return this._srcObject;
+          },
+          set: function(stream) {
+            var self = this;
+            // Use _srcObject as a private property for this shim
+            this._srcObject = stream;
+            if (this.src) {
+              URL.revokeObjectURL(this.src);
+            }
+
+            if (!stream) {
+              this.src = '';
+              return undefined;
+            }
+            this.src = URL.createObjectURL(stream);
+            // We need to recreate the blob url when a track is added or
+            // removed. Doing it manually since we want to avoid a recursion.
+            stream.addEventListener('addtrack', function() {
+              if (self.src) {
+                URL.revokeObjectURL(self.src);
+              }
+              self.src = URL.createObjectURL(stream);
+            });
+            stream.addEventListener('removetrack', function() {
+              if (self.src) {
+                URL.revokeObjectURL(self.src);
+              }
+              self.src = URL.createObjectURL(stream);
+            });
+          }
+        });
+      }
+    }
+  },
+
+  shimPeerConnection: function(window) {
+    var browserDetails = utils.detectBrowser(window);
+
+    // The RTCPeerConnection object.
+    if (!window.RTCPeerConnection) {
+      window.RTCPeerConnection = function(pcConfig, pcConstraints) {
+        // Translate iceTransportPolicy to iceTransports,
+        // see https://code.google.com/p/webrtc/issues/detail?id=4869
+        // this was fixed in M56 along with unprefixing RTCPeerConnection.
+        logging('PeerConnection');
+        if (pcConfig && pcConfig.iceTransportPolicy) {
+          pcConfig.iceTransports = pcConfig.iceTransportPolicy;
+        }
+
+        return new window.webkitRTCPeerConnection(pcConfig, pcConstraints);
+      };
+      window.RTCPeerConnection.prototype =
+          window.webkitRTCPeerConnection.prototype;
+      // wrap static methods. Currently just generateCertificate.
+      if (window.webkitRTCPeerConnection.generateCertificate) {
+        Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
+          get: function() {
+            return window.webkitRTCPeerConnection.generateCertificate;
+          }
+        });
+      }
+    } else {
+      // migrate from non-spec RTCIceServer.url to RTCIceServer.urls
+      var OrigPeerConnection = window.RTCPeerConnection;
+      window.RTCPeerConnection = function(pcConfig, pcConstraints) {
+        if (pcConfig && pcConfig.iceServers) {
+          var newIceServers = [];
+          for (var i = 0; i < pcConfig.iceServers.length; i++) {
+            var server = pcConfig.iceServers[i];
+            if (!server.hasOwnProperty('urls') &&
+                server.hasOwnProperty('url')) {
+              console.warn('RTCIceServer.url is deprecated! Use urls instead.');
+              server = JSON.parse(JSON.stringify(server));
+              server.urls = server.url;
+              newIceServers.push(server);
+            } else {
+              newIceServers.push(pcConfig.iceServers[i]);
+            }
+          }
+          pcConfig.iceServers = newIceServers;
+        }
+        return new OrigPeerConnection(pcConfig, pcConstraints);
+      };
+      window.RTCPeerConnection.prototype = OrigPeerConnection.prototype;
+      // wrap static methods. Currently just generateCertificate.
+      Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
+        get: function() {
+          return OrigPeerConnection.generateCertificate;
+        }
+      });
+    }
+
+    var origGetStats = window.RTCPeerConnection.prototype.getStats;
+    window.RTCPeerConnection.prototype.getStats = function(selector,
+        successCallback, errorCallback) {
+      var self = this;
+      var args = arguments;
+
+      // If selector is a function then we are in the old style stats so just
+      // pass back the original getStats format to avoid breaking old users.
+      if (arguments.length > 0 && typeof selector === 'function') {
+        return origGetStats.apply(this, arguments);
+      }
+
+      // When spec-style getStats is supported, return those when called with
+      // either no arguments or the selector argument is null.
+      if (origGetStats.length === 0 && (arguments.length === 0 ||
+          typeof arguments[0] !== 'function')) {
+        return origGetStats.apply(this, []);
+      }
+
+      var fixChromeStats_ = function(response) {
+        var standardReport = {};
+        var reports = response.result();
+        reports.forEach(function(report) {
+          var standardStats = {
+            id: report.id,
+            timestamp: report.timestamp,
+            type: {
+              localcandidate: 'local-candidate',
+              remotecandidate: 'remote-candidate'
+            }[report.type] || report.type
+          };
+          report.names().forEach(function(name) {
+            standardStats[name] = report.stat(name);
+          });
+          standardReport[standardStats.id] = standardStats;
+        });
+
+        return standardReport;
+      };
+
+      // shim getStats with maplike support
+      var makeMapStats = function(stats) {
+        return new Map(Object.keys(stats).map(function(key) {
+          return [key, stats[key]];
+        }));
+      };
+
+      if (arguments.length >= 2) {
+        var successCallbackWrapper_ = function(response) {
+          args[1](makeMapStats(fixChromeStats_(response)));
+        };
+
+        return origGetStats.apply(this, [successCallbackWrapper_,
+          arguments[0]]);
+      }
+
+      // promise-support
+      return new Promise(function(resolve, reject) {
+        origGetStats.apply(self, [
+          function(response) {
+            resolve(makeMapStats(fixChromeStats_(response)));
+          }, reject]);
+      }).then(successCallback, errorCallback);
+    };
+
+    // add promise support -- natively available in Chrome 51
+    if (browserDetails.version < 51) {
+      ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
+          .forEach(function(method) {
+            var nativeMethod = window.RTCPeerConnection.prototype[method];
+            window.RTCPeerConnection.prototype[method] = function() {
+              var args = arguments;
+              var self = this;
+              var promise = new Promise(function(resolve, reject) {
+                nativeMethod.apply(self, [args[0], resolve, reject]);
+              });
+              if (args.length < 2) {
+                return promise;
+              }
+              return promise.then(function() {
+                args[1].apply(null, []);
+              },
+              function(err) {
+                if (args.length >= 3) {
+                  args[2].apply(null, [err]);
+                }
+              });
+            };
+          });
+    }
+
+    // promise support for createOffer and createAnswer. Available (without
+    // bugs) since M52: crbug/619289
+    if (browserDetails.version < 52) {
+      ['createOffer', 'createAnswer'].forEach(function(method) {
+        var nativeMethod = window.RTCPeerConnection.prototype[method];
+        window.RTCPeerConnection.prototype[method] = function() {
+          var self = this;
+          if (arguments.length < 1 || (arguments.length === 1 &&
+              typeof arguments[0] === 'object')) {
+            var opts = arguments.length === 1 ? arguments[0] : undefined;
+            return new Promise(function(resolve, reject) {
+              nativeMethod.apply(self, [resolve, reject, opts]);
+            });
+          }
+          return nativeMethod.apply(this, arguments);
+        };
+      });
+    }
+
+    // shim implicit creation of RTCSessionDescription/RTCIceCandidate
+    ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
+        .forEach(function(method) {
+          var nativeMethod = window.RTCPeerConnection.prototype[method];
+          window.RTCPeerConnection.prototype[method] = function() {
+            arguments[0] = new ((method === 'addIceCandidate') ?
+                window.RTCIceCandidate :
+                window.RTCSessionDescription)(arguments[0]);
+            return nativeMethod.apply(this, arguments);
+          };
+        });
+
+    // support for addIceCandidate(null or undefined)
+    var nativeAddIceCandidate =
+        window.RTCPeerConnection.prototype.addIceCandidate;
+    window.RTCPeerConnection.prototype.addIceCandidate = function() {
+      if (!arguments[0]) {
+        if (arguments[1]) {
+          arguments[1].apply(null);
+        }
+        return Promise.resolve();
+      }
+      return nativeAddIceCandidate.apply(this, arguments);
+    };
+  }
+};
+
+
+// Expose public methods.
+module.exports = {
+  shimMediaStream: chromeShim.shimMediaStream,
+  shimOnTrack: chromeShim.shimOnTrack,
+  shimGetSendersWithDtmf: chromeShim.shimGetSendersWithDtmf,
+  shimSourceObject: chromeShim.shimSourceObject,
+  shimPeerConnection: chromeShim.shimPeerConnection,
+  shimGetUserMedia: require('./getusermedia')
+};
+
+},{"../utils.js":12,"./getusermedia":5}],5:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+var utils = require('../utils.js');
+var logging = utils.log;
+
+// Expose public methods.
+module.exports = function(window) {
+  var browserDetails = utils.detectBrowser(window);
+  var navigator = window && window.navigator;
+
+  var constraintsToChrome_ = function(c) {
+    if (typeof c !== 'object' || c.mandatory || c.optional) {
+      return c;
+    }
+    var cc = {};
+    Object.keys(c).forEach(function(key) {
+      if (key === 'require' || key === 'advanced' || key === 'mediaSource') {
+        return;
+      }
+      var r = (typeof c[key] === 'object') ? c[key] : {ideal: c[key]};
+      if (r.exact !== undefined && typeof r.exact === 'number') {
+        r.min = r.max = r.exact;
+      }
+      var oldname_ = function(prefix, name) {
+        if (prefix) {
+          return prefix + name.charAt(0).toUpperCase() + name.slice(1);
+        }
+        return (name === 'deviceId') ? 'sourceId' : name;
+      };
+      if (r.ideal !== undefined) {
+        cc.optional = cc.optional || [];
+        var oc = {};
+        if (typeof r.ideal === 'number') {
+          oc[oldname_('min', key)] = r.ideal;
+          cc.optional.push(oc);
+          oc = {};
+          oc[oldname_('max', key)] = r.ideal;
+          cc.optional.push(oc);
+        } else {
+          oc[oldname_('', key)] = r.ideal;
+          cc.optional.push(oc);
+        }
+      }
+      if (r.exact !== undefined && typeof r.exact !== 'number') {
+        cc.mandatory = cc.mandatory || {};
+        cc.mandatory[oldname_('', key)] = r.exact;
+      } else {
+        ['min', 'max'].forEach(function(mix) {
+          if (r[mix] !== undefined) {
+            cc.mandatory = cc.mandatory || {};
+            cc.mandatory[oldname_(mix, key)] = r[mix];
+          }
+        });
+      }
+    });
+    if (c.advanced) {
+      cc.optional = (cc.optional || []).concat(c.advanced);
+    }
+    return cc;
+  };
+
+  var shimConstraints_ = function(constraints, func) {
+    constraints = JSON.parse(JSON.stringify(constraints));
+    if (constraints && typeof constraints.audio === 'object') {
+      var remap = function(obj, a, b) {
+        if (a in obj && !(b in obj)) {
+          obj[b] = obj[a];
+          delete obj[a];
+        }
+      };
+      constraints = JSON.parse(JSON.stringify(constraints));
+      remap(constraints.audio, 'autoGainControl', 'googAutoGainControl');
+      remap(constraints.audio, 'noiseSuppression', 'googNoiseSuppression');
+      constraints.audio = constraintsToChrome_(constraints.audio);
+    }
+    if (constraints && typeof constraints.video === 'object') {
+      // Shim facingMode for mobile & surface pro.
+      var face = constraints.video.facingMode;
+      face = face && ((typeof face === 'object') ? face : {ideal: face});
+      var getSupportedFacingModeLies = browserDetails.version < 61;
+
+      if ((face && (face.exact === 'user' || face.exact === 'environment' ||
+                    face.ideal === 'user' || face.ideal === 'environment')) &&
+          !(navigator.mediaDevices.getSupportedConstraints &&
+            navigator.mediaDevices.getSupportedConstraints().facingMode &&
+            !getSupportedFacingModeLies)) {
+        delete constraints.video.facingMode;
+        var matches;
+        if (face.exact === 'environment' || face.ideal === 'environment') {
+          matches = ['back', 'rear'];
+        } else if (face.exact === 'user' || face.ideal === 'user') {
+          matches = ['front'];
+        }
+        if (matches) {
+          // Look for matches in label, or use last cam for back (typical).
+          return navigator.mediaDevices.enumerateDevices()
+          .then(function(devices) {
+            devices = devices.filter(function(d) {
+              return d.kind === 'videoinput';
+            });
+            var dev = devices.find(function(d) {
+              return matches.some(function(match) {
+                return d.label.toLowerCase().indexOf(match) !== -1;
+              });
+            });
+            if (!dev && devices.length && matches.indexOf('back') !== -1) {
+              dev = devices[devices.length - 1]; // more likely the back cam
+            }
+            if (dev) {
+              constraints.video.deviceId = face.exact ? {exact: dev.deviceId} :
+                                                        {ideal: dev.deviceId};
+            }
+            constraints.video = constraintsToChrome_(constraints.video);
+            logging('chrome: ' + JSON.stringify(constraints));
+            return func(constraints);
+          });
+        }
+      }
+      constraints.video = constraintsToChrome_(constraints.video);
+    }
+    logging('chrome: ' + JSON.stringify(constraints));
+    return func(constraints);
+  };
+
+  var shimError_ = function(e) {
+    return {
+      name: {
+        PermissionDeniedError: 'NotAllowedError',
+        InvalidStateError: 'NotReadableError',
+        DevicesNotFoundError: 'NotFoundError',
+        ConstraintNotSatisfiedError: 'OverconstrainedError',
+        TrackStartError: 'NotReadableError',
+        MediaDeviceFailedDueToShutdown: 'NotReadableError',
+        MediaDeviceKillSwitchOn: 'NotReadableError'
+      }[e.name] || e.name,
+      message: e.message,
+      constraint: e.constraintName,
+      toString: function() {
+        return this.name + (this.message && ': ') + this.message;
+      }
+    };
+  };
+
+  var getUserMedia_ = function(constraints, onSuccess, onError) {
+    shimConstraints_(constraints, function(c) {
+      navigator.webkitGetUserMedia(c, onSuccess, function(e) {
+        onError(shimError_(e));
+      });
+    });
+  };
+
+  navigator.getUserMedia = getUserMedia_;
+
+  // Returns the result of getUserMedia as a Promise.
+  var getUserMediaPromise_ = function(constraints) {
+    return new Promise(function(resolve, reject) {
+      navigator.getUserMedia(constraints, resolve, reject);
+    });
+  };
+
+  if (!navigator.mediaDevices) {
+    navigator.mediaDevices = {
+      getUserMedia: getUserMediaPromise_,
+      enumerateDevices: function() {
+        return new Promise(function(resolve) {
+          var kinds = {audio: 'audioinput', video: 'videoinput'};
+          return window.MediaStreamTrack.getSources(function(devices) {
+            resolve(devices.map(function(device) {
+              return {label: device.label,
+                kind: kinds[device.kind],
+                deviceId: device.id,
+                groupId: ''};
+            }));
+          });
+        });
+      },
+      getSupportedConstraints: function() {
+        return {
+          deviceId: true, echoCancellation: true, facingMode: true,
+          frameRate: true, height: true, width: true
+        };
+      }
+    };
+  }
+
+  // A shim for getUserMedia method on the mediaDevices object.
+  // TODO(KaptenJansson) remove once implemented in Chrome stable.
+  if (!navigator.mediaDevices.getUserMedia) {
+    navigator.mediaDevices.getUserMedia = function(constraints) {
+      return getUserMediaPromise_(constraints);
+    };
+  } else {
+    // Even though Chrome 45 has navigator.mediaDevices and a getUserMedia
+    // function which returns a Promise, it does not accept spec-style
+    // constraints.
+    var origGetUserMedia = navigator.mediaDevices.getUserMedia.
+        bind(navigator.mediaDevices);
+    navigator.mediaDevices.getUserMedia = function(cs) {
+      return shimConstraints_(cs, function(c) {
+        return origGetUserMedia(c).then(function(stream) {
+          if (c.audio && !stream.getAudioTracks().length ||
+              c.video && !stream.getVideoTracks().length) {
+            stream.getTracks().forEach(function(track) {
+              track.stop();
+            });
+            throw new DOMException('', 'NotFoundError');
+          }
+          return stream;
+        }, function(e) {
+          return Promise.reject(shimError_(e));
+        });
+      });
+    };
+  }
+
+  // Dummy devicechange event methods.
+  // TODO(KaptenJansson) remove once implemented in Chrome stable.
+  if (typeof navigator.mediaDevices.addEventListener === 'undefined') {
+    navigator.mediaDevices.addEventListener = function() {
+      logging('Dummy mediaDevices.addEventListener called.');
+    };
+  }
+  if (typeof navigator.mediaDevices.removeEventListener === 'undefined') {
+    navigator.mediaDevices.removeEventListener = function() {
+      logging('Dummy mediaDevices.removeEventListener called.');
+    };
+  }
+};
+
+},{"../utils.js":12}],6:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+
+var utils = require('../utils');
+var shimRTCPeerConnection = require('./rtcpeerconnection_shim');
+
+module.exports = {
+  shimGetUserMedia: require('./getusermedia'),
+  shimPeerConnection: function(window) {
+    var browserDetails = utils.detectBrowser(window);
+
+    if (window.RTCIceGatherer) {
+      // ORTC defines an RTCIceCandidate object but no constructor.
+      // Not implemented in Edge.
+      if (!window.RTCIceCandidate) {
+        window.RTCIceCandidate = function(args) {
+          return args;
+        };
+      }
+      // ORTC does not have a session description object but
+      // other browsers (i.e. Chrome) that will support both PC and ORTC
+      // in the future might have this defined already.
+      if (!window.RTCSessionDescription) {
+        window.RTCSessionDescription = function(args) {
+          return args;
+        };
+      }
+      // this adds an additional event listener to MediaStrackTrack that signals
+      // when a tracks enabled property was changed. Workaround for a bug in
+      // addStream, see below. No longer required in 15025+
+      if (browserDetails.version < 15025) {
+        var origMSTEnabled = Object.getOwnPropertyDescriptor(
+            window.MediaStreamTrack.prototype, 'enabled');
+        Object.defineProperty(window.MediaStreamTrack.prototype, 'enabled', {
+          set: function(value) {
+            origMSTEnabled.set.call(this, value);
+            var ev = new Event('enabled');
+            ev.enabled = value;
+            this.dispatchEvent(ev);
+          }
+        });
+      }
+    }
+    window.RTCPeerConnection =
+        shimRTCPeerConnection(window, browserDetails.version);
+  },
+  shimReplaceTrack: function(window) {
+    // ORTC has replaceTrack -- https://github.com/w3c/ortc/issues/614
+    if (window.RTCRtpSender &&
+        !('replaceTrack' in window.RTCRtpSender.prototype)) {
+      window.RTCRtpSender.prototype.replaceTrack =
+          window.RTCRtpSender.prototype.setTrack;
+    }
+  }
+};
+
+},{"../utils":12,"./getusermedia":7,"./rtcpeerconnection_shim":8}],7:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+
+// Expose public methods.
+module.exports = function(window) {
+  var navigator = window && window.navigator;
+
+  var shimError_ = function(e) {
+    return {
+      name: {PermissionDeniedError: 'NotAllowedError'}[e.name] || e.name,
+      message: e.message,
+      constraint: e.constraint,
+      toString: function() {
+        return this.name;
+      }
+    };
+  };
+
+  // getUserMedia error shim.
+  var origGetUserMedia = navigator.mediaDevices.getUserMedia.
+      bind(navigator.mediaDevices);
+  navigator.mediaDevices.getUserMedia = function(c) {
+    return origGetUserMedia(c).catch(function(e) {
+      return Promise.reject(shimError_(e));
+    });
+  };
+};
+
+},{}],8:[function(require,module,exports){
+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+
+var SDPUtils = require('sdp');
+
+// sort tracks such that they follow an a-v-a-v...
+// pattern.
+function sortTracks(tracks) {
+  var audioTracks = tracks.filter(function(track) {
+    return track.kind === 'audio';
+  });
+  var videoTracks = tracks.filter(function(track) {
+    return track.kind === 'video';
+  });
+  tracks = [];
+  while (audioTracks.length || videoTracks.length) {
+    if (audioTracks.length) {
+      tracks.push(audioTracks.shift());
+    }
+    if (videoTracks.length) {
+      tracks.push(videoTracks.shift());
+    }
+  }
+  return tracks;
+}
+
+// Edge does not like
+// 1) stun:
+// 2) turn: that does not have all of turn:host:port?transport=udp
+// 3) turn: with ipv6 addresses
+// 4) turn: occurring muliple times
+function filterIceServers(iceServers, edgeVersion) {
+  var hasTurn = false;
+  iceServers = JSON.parse(JSON.stringify(iceServers));
+  return iceServers.filter(function(server) {
+    if (server && (server.urls || server.url)) {
+      var urls = server.urls || server.url;
+      if (server.url && !server.urls) {
+        console.warn('RTCIceServer.url is deprecated! Use urls instead.');
+      }
+      var isString = typeof urls === 'string';
+      if (isString) {
+        urls = [urls];
+      }
+      urls = urls.filter(function(url) {
+        var validTurn = url.indexOf('turn:') === 0 &&
+            url.indexOf('transport=udp') !== -1 &&
+            url.indexOf('turn:[') === -1 &&
+            !hasTurn;
+
+        if (validTurn) {
+          hasTurn = true;
+          return true;
+        }
+        return url.indexOf('stun:') === 0 && edgeVersion >= 14393;
+      });
+
+      delete server.url;
+      server.urls = isString ? urls[0] : urls;
+      return !!urls.length;
+    }
+    return false;
+  });
+}
+
+// Determines the intersection of local and remote capabilities.
+function getCommonCapabilities(localCapabilities, remoteCapabilities) {
+  var commonCapabilities = {
+    codecs: [],
+    headerExtensions: [],
+    fecMechanisms: []
+  };
+
+  var findCodecByPayloadType = function(pt, codecs) {
+    pt = parseInt(pt, 10);
+    for (var i = 0; i < codecs.length; i++) {
+      if (codecs[i].payloadType === pt ||
+          codecs[i].preferredPayloadType === pt) {
+        return codecs[i];
+      }
+    }
+  };
+
+  var rtxCapabilityMatches = function(lRtx, rRtx, lCodecs, rCodecs) {
+    var lCodec = findCodecByPayloadType(lRtx.parameters.apt, lCodecs);
+    var rCodec = findCodecByPayloadType(rRtx.parameters.apt, rCodecs);
+    return lCodec && rCodec &&
+        lCodec.name.toLowerCase() === rCodec.name.toLowerCase();
+  };
+
+  localCapabilities.codecs.forEach(function(lCodec) {
+    for (var i = 0; i < remoteCapabilities.codecs.length; i++) {
+      var rCodec = remoteCapabilities.codecs[i];
+      if (lCodec.name.toLowerCase() === rCodec.name.toLowerCase() &&
+          lCodec.clockRate === rCodec.clockRate) {
+        if (lCodec.name.toLowerCase() === 'rtx' &&
+            lCodec.parameters && rCodec.parameters.apt) {
+          // for RTX we need to find the local rtx that has a apt
+          // which points to the same local codec as the remote one.
+          if (!rtxCapabilityMatches(lCodec, rCodec,
+              localCapabilities.codecs, remoteCapabilities.codecs)) {
+            continue;
+          }
+        }
+        rCodec = JSON.parse(JSON.stringify(rCodec)); // deepcopy
+        // number of channels is the highest common number of channels
+        rCodec.numChannels = Math.min(lCodec.numChannels,
+            rCodec.numChannels);
+        // push rCodec so we reply with offerer payload type
+        commonCapabilities.codecs.push(rCodec);
+
+        // determine common feedback mechanisms
+        rCodec.rtcpFeedback = rCodec.rtcpFeedback.filter(function(fb) {
+          for (var j = 0; j < lCodec.rtcpFeedback.length; j++) {
+            if (lCodec.rtcpFeedback[j].type === fb.type &&
+                lCodec.rtcpFeedback[j].parameter === fb.parameter) {
+              return true;
+            }
+          }
+          return false;
+        });
+        // FIXME: also need to determine .parameters
+        //  see https://github.com/openpeer/ortc/issues/569
+        break;
+      }
+    }
+  });
+
+  localCapabilities.headerExtensions.forEach(function(lHeaderExtension) {
+    for (var i = 0; i < remoteCapabilities.headerExtensions.length;
+         i++) {
+      var rHeaderExtension = remoteCapabilities.headerExtensions[i];
+      if (lHeaderExtension.uri === rHeaderExtension.uri) {
+        commonCapabilities.headerExtensions.push(rHeaderExtension);
+        break;
+      }
+    }
+  });
+
+  // FIXME: fecMechanisms
+  return commonCapabilities;
+}
+
+// is action=setLocalDescription with type allowed in signalingState
+function isActionAllowedInSignalingState(action, type, signalingState) {
+  return {
+    offer: {
+      setLocalDescription: ['stable', 'have-local-offer'],
+      setRemoteDescription: ['stable', 'have-remote-offer']
+    },
+    answer: {
+      setLocalDescription: ['have-remote-offer', 'have-local-pranswer'],
+      setRemoteDescription: ['have-local-offer', 'have-remote-pranswer']
+    }
+  }[type][action].indexOf(signalingState) !== -1;
+}
+
+module.exports = function(window, edgeVersion) {
+  var RTCPeerConnection = function(config) {
+    var self = this;
+
+    var _eventTarget = document.createDocumentFragment();
+    ['addEventListener', 'removeEventListener', 'dispatchEvent']
+        .forEach(function(method) {
+          self[method] = _eventTarget[method].bind(_eventTarget);
+        });
+
+    this.needNegotiation = false;
+
+    this.onicecandidate = null;
+    this.onaddstream = null;
+    this.ontrack = null;
+    this.onremovestream = null;
+    this.onsignalingstatechange = null;
+    this.oniceconnectionstatechange = null;
+    this.onicegatheringstatechange = null;
+    this.onnegotiationneeded = null;
+    this.ondatachannel = null;
+    this.canTrickleIceCandidates = null;
+
+    this.localStreams = [];
+    this.remoteStreams = [];
+    this.getLocalStreams = function() {
+      return self.localStreams;
+    };
+    this.getRemoteStreams = function() {
+      return self.remoteStreams;
+    };
+
+    this.localDescription = new window.RTCSessionDescription({
+      type: '',
+      sdp: ''
+    });
+    this.remoteDescription = new window.RTCSessionDescription({
+      type: '',
+      sdp: ''
+    });
+    this.signalingState = 'stable';
+    this.iceConnectionState = 'new';
+    this.iceGatheringState = 'new';
+
+    this.iceOptions = {
+      gatherPolicy: 'all',
+      iceServers: []
+    };
+    if (config && config.iceTransportPolicy) {
+      switch (config.iceTransportPolicy) {
+        case 'all':
+        case 'relay':
+          this.iceOptions.gatherPolicy = config.iceTransportPolicy;
+          break;
+        default:
+          // don't set iceTransportPolicy.
+          break;
+      }
+    }
+    this.usingBundle = config && config.bundlePolicy === 'max-bundle';
+
+    if (config && config.iceServers) {
+      this.iceOptions.iceServers = filterIceServers(config.iceServers,
+          edgeVersion);
+    }
+    this._config = config || {};
+
+    // per-track iceGathers, iceTransports, dtlsTransports, rtpSenders, ...
+    // everything that is needed to describe a SDP m-line.
+    this.transceivers = [];
+
+    // since the iceGatherer is currently created in createOffer but we
+    // must not emit candidates until after setLocalDescription we buffer
+    // them in this array.
+    this._localIceCandidatesBuffer = [];
+
+    this._sdpSessionId = SDPUtils.generateSessionId();
+  };
+
+  RTCPeerConnection.prototype._emitGatheringStateChange = function() {
+    var event = new Event('icegatheringstatechange');
+    this.dispatchEvent(event);
+    if (this.onicegatheringstatechange !== null) {
+      this.onicegatheringstatechange(event);
+    }
+  };
+
+  RTCPeerConnection.prototype._emitBufferedCandidates = function() {
+    var self = this;
+    var sections = SDPUtils.splitSections(self.localDescription.sdp);
+    // FIXME: need to apply ice candidates in a way which is async but
+    // in-order
+    this._localIceCandidatesBuffer.forEach(function(event) {
+      var end = !event.candidate || Object.keys(event.candidate).length === 0;
+      if (end) {
+        for (var j = 1; j < sections.length; j++) {
+          if (sections[j].indexOf('\r\na=end-of-candidates\r\n') === -1) {
+            sections[j] += 'a=end-of-candidates\r\n';
+          }
+        }
+      } else {
+        sections[event.candidate.sdpMLineIndex + 1] +=
+            'a=' + event.candidate.candidate + '\r\n';
+      }
+      self.localDescription.sdp = sections.join('');
+      self.dispatchEvent(event);
+      if (self.onicecandidate !== null) {
+        self.onicecandidate(event);
+      }
+      if (!event.candidate && self.iceGatheringState !== 'complete') {
+        var complete = self.transceivers.every(function(transceiver) {
+          return transceiver.iceGatherer &&
+              transceiver.iceGatherer.state === 'completed';
+        });
+        if (complete && self.iceGatheringStateChange !== 'complete') {
+          self.iceGatheringState = 'complete';
+          self._emitGatheringStateChange();
+        }
+      }
+    });
+    this._localIceCandidatesBuffer = [];
+  };
+
+  RTCPeerConnection.prototype.getConfiguration = function() {
+    return this._config;
+  };
+
+  // internal helper to create a transceiver object.
+  // (whih is not yet the same as the WebRTC 1.0 transceiver)
+  RTCPeerConnection.prototype._createTransceiver = function(kind) {
+    var hasBundleTransport = this.transceivers.length > 0;
+    var transceiver = {
+      track: null,
+      iceGatherer: null,
+      iceTransport: null,
+      dtlsTransport: null,
+      localCapabilities: null,
+      remoteCapabilities: null,
+      rtpSender: null,
+      rtpReceiver: null,
+      kind: kind,
+      mid: null,
+      sendEncodingParameters: null,
+      recvEncodingParameters: null,
+      stream: null,
+      wantReceive: true
+    };
+    if (this.usingBundle && hasBundleTransport) {
+      transceiver.iceTransport = this.transceivers[0].iceTransport;
+      transceiver.dtlsTransport = this.transceivers[0].dtlsTransport;
+    } else {
+      var transports = this._createIceAndDtlsTransports();
+      transceiver.iceTransport = transports.iceTransport;
+      transceiver.dtlsTransport = transports.dtlsTransport;
+    }
+    this.transceivers.push(transceiver);
+    return transceiver;
+  };
+
+  RTCPeerConnection.prototype.addTrack = function(track, stream) {
+    var transceiver;
+    for (var i = 0; i < this.transceivers.length; i++) {
+      if (!this.transceivers[i].track &&
+          this.transceivers[i].kind === track.kind) {
+        transceiver = this.transceivers[i];
+      }
+    }
+    if (!transceiver) {
+      transceiver = this._createTransceiver(track.kind);
+    }
+
+    transceiver.track = track;
+    transceiver.stream = stream;
+    transceiver.rtpSender = new window.RTCRtpSender(track,
+        transceiver.dtlsTransport);
+
+    this._maybeFireNegotiationNeeded();
+    return transceiver.rtpSender;
+  };
+
+  RTCPeerConnection.prototype.addStream = function(stream) {
+    var self = this;
+    if (edgeVersion >= 15025) {
+      this.localStreams.push(stream);
+      stream.getTracks().forEach(function(track) {
+        self.addTrack(track, stream);
+      });
+    } else {
+      // Clone is necessary for local demos mostly, attaching directly
+      // to two different senders does not work (build 10547).
+      // Fixed in 15025 (or earlier)
+      var clonedStream = stream.clone();
+      stream.getTracks().forEach(function(track, idx) {
+        var clonedTrack = clonedStream.getTracks()[idx];
+        track.addEventListener('enabled', function(event) {
+          clonedTrack.enabled = event.enabled;
+        });
+      });
+      clonedStream.getTracks().forEach(function(track) {
+        self.addTrack(track, clonedStream);
+      });
+      this.localStreams.push(clonedStream);
+    }
+    this._maybeFireNegotiationNeeded();
+  };
+
+  RTCPeerConnection.prototype.removeStream = function(stream) {
+    var idx = this.localStreams.indexOf(stream);
+    if (idx > -1) {
+      this.localStreams.splice(idx, 1);
+      this._maybeFireNegotiationNeeded();
+    }
+  };
+
+  RTCPeerConnection.prototype.getSenders = function() {
+    return this.transceivers.filter(function(transceiver) {
+      return !!transceiver.rtpSender;
+    })
+    .map(function(transceiver) {
+      return transceiver.rtpSender;
+    });
+  };
+
+  RTCPeerConnection.prototype.getReceivers = function() {
+    return this.transceivers.filter(function(transceiver) {
+      return !!transceiver.rtpReceiver;
+    })
+    .map(function(transceiver) {
+      return transceiver.rtpReceiver;
+    });
+  };
+
+  // Create ICE gatherer and hook it up.
+  RTCPeerConnection.prototype._createIceGatherer = function(mid,
+      sdpMLineIndex) {
+    var self = this;
+    var iceGatherer = new window.RTCIceGatherer(self.iceOptions);
+    iceGatherer.onlocalcandidate = function(evt) {
+      var event = new Event('icecandidate');
+      event.candidate = {sdpMid: mid, sdpMLineIndex: sdpMLineIndex};
+
+      var cand = evt.candidate;
+      var end = !cand || Object.keys(cand).length === 0;
+      // Edge emits an empty object for RTCIceCandidateCompleteâ€Ĩ
+      if (end) {
+        // polyfill since RTCIceGatherer.state is not implemented in
+        // Edge 10547 yet.
+        if (iceGatherer.state === undefined) {
+          iceGatherer.state = 'completed';
+        }
+      } else {
+        // RTCIceCandidate doesn't have a component, needs to be added
+        cand.component = 1;
+        event.candidate.candidate = SDPUtils.writeCandidate(cand);
+      }
+
+      // update local description.
+      var sections = SDPUtils.splitSections(self.localDescription.sdp);
+      if (!end) {
+        sections[event.candidate.sdpMLineIndex + 1] +=
+            'a=' + event.candidate.candidate + '\r\n';
+      } else {
+        sections[event.candidate.sdpMLineIndex + 1] +=
+            'a=end-of-candidates\r\n';
+      }
+      self.localDescription.sdp = sections.join('');
+      var transceivers = self._pendingOffer ? self._pendingOffer :
+          self.transceivers;
+      var complete = transceivers.every(function(transceiver) {
+        return transceiver.iceGatherer &&
+            transceiver.iceGatherer.state === 'completed';
+      });
+
+      // Emit candidate if localDescription is set.
+      // Also emits null candidate when all gatherers are complete.
+      switch (self.iceGatheringState) {
+        case 'new':
+          if (!end) {
+            self._localIceCandidatesBuffer.push(event);
+          }
+          if (end && complete) {
+            self._localIceCandidatesBuffer.push(
+                new Event('icecandidate'));
+          }
+          break;
+        case 'gathering':
+          self._emitBufferedCandidates();
+          if (!end) {
+            self.dispatchEvent(event);
+            if (self.onicecandidate !== null) {
+              self.onicecandidate(event);
+            }
+          }
+          if (complete) {
+            self.dispatchEvent(new Event('icecandidate'));
+            if (self.onicecandidate !== null) {
+              self.onicecandidate(new Event('icecandidate'));
+            }
+            self.iceGatheringState = 'complete';
+            self._emitGatheringStateChange();
+          }
+          break;
+        case 'complete':
+          // should not happen... currently!
+          break;
+        default: // no-op.
+          break;
+      }
+    };
+    return iceGatherer;
+  };
+
+  // Create ICE transport and DTLS transport.
+  RTCPeerConnection.prototype._createIceAndDtlsTransports = function() {
+    var self = this;
+    var iceTransport = new window.RTCIceTransport(null);
+    iceTransport.onicestatechange = function() {
+      self._updateConnectionState();
+    };
+
+    var dtlsTransport = new window.RTCDtlsTransport(iceTransport);
+    dtlsTransport.ondtlsstatechange = function() {
+      self._updateConnectionState();
+    };
+    dtlsTransport.onerror = function() {
+      // onerror does not set state to failed by itself.
+      Object.defineProperty(dtlsTransport, 'state',
+          {value: 'failed', writable: true});
+      self._updateConnectionState();
+    };
+
+    return {
+      iceTransport: iceTransport,
+      dtlsTransport: dtlsTransport
+    };
+  };
+
+  // Destroy ICE gatherer, ICE transport and DTLS transport.
+  // Without triggering the callbacks.
+  RTCPeerConnection.prototype._disposeIceAndDtlsTransports = function(
+      sdpMLineIndex) {
+    var iceGatherer = this.transceivers[sdpMLineIndex].iceGatherer;
+    if (iceGatherer) {
+      delete iceGatherer.onlocalcandidate;
+      delete this.transceivers[sdpMLineIndex].iceGatherer;
+    }
+    var iceTransport = this.transceivers[sdpMLineIndex].iceTransport;
+    if (iceTransport) {
+      delete iceTransport.onicestatechange;
+      delete this.transceivers[sdpMLineIndex].iceTransport;
+    }
+    var dtlsTransport = this.transceivers[sdpMLineIndex].dtlsTransport;
+    if (dtlsTransport) {
+      delete dtlsTransport.ondtlssttatechange;
+      delete dtlsTransport.onerror;
+      delete this.transceivers[sdpMLineIndex].dtlsTransport;
+    }
+  };
+
+  // Start the RTP Sender and Receiver for a transceiver.
+  RTCPeerConnection.prototype._transceive = function(transceiver,
+      send, recv) {
+    var params = getCommonCapabilities(transceiver.localCapabilities,
+        transceiver.remoteCapabilities);
+    if (send && transceiver.rtpSender) {
+      params.encodings = transceiver.sendEncodingParameters;
+      params.rtcp = {
+        cname: SDPUtils.localCName,
+        compound: transceiver.rtcpParameters.compound
+      };
+      if (transceiver.recvEncodingParameters.length) {
+        params.rtcp.ssrc = transceiver.recvEncodingParameters[0].ssrc;
+      }
+      transceiver.rtpSender.send(params);
+    }
+    if (recv && transceiver.rtpReceiver) {
+      // remove RTX field in Edge 14942
+      if (transceiver.kind === 'video'
+          && transceiver.recvEncodingParameters
+          && edgeVersion < 15019) {
+        transceiver.recvEncodingParameters.forEach(function(p) {
+          delete p.rtx;
+        });
+      }
+      params.encodings = transceiver.recvEncodingParameters;
+      params.rtcp = {
+        cname: transceiver.rtcpParameters.cname,
+        compound: transceiver.rtcpParameters.compound
+      };
+      if (transceiver.sendEncodingParameters.length) {
+        params.rtcp.ssrc = transceiver.sendEncodingParameters[0].ssrc;
+      }
+      transceiver.rtpReceiver.receive(params);
+    }
+  };
+
+  RTCPeerConnection.prototype.setLocalDescription = function(description) {
+    var self = this;
+
+    if (!isActionAllowedInSignalingState('setLocalDescription',
+        description.type, this.signalingState)) {
+      var e = new Error('Can not set local ' + description.type +
+          ' in state ' + this.signalingState);
+      e.name = 'InvalidStateError';
+      if (arguments.length > 2 && typeof arguments[2] === 'function') {
+        window.setTimeout(arguments[2], 0, e);
+      }
+      return Promise.reject(e);
+    }
+
+    var sections;
+    var sessionpart;
+    if (description.type === 'offer') {
+      // FIXME: What was the purpose of this empty if statement?
+      // if (!this._pendingOffer) {
+      // } else {
+      if (this._pendingOffer) {
+        // VERY limited support for SDP munging. Limited to:
+        // * changing the order of codecs
+        sections = SDPUtils.splitSections(description.sdp);
+        sessionpart = sections.shift();
+        sections.forEach(function(mediaSection, sdpMLineIndex) {
+          var caps = SDPUtils.parseRtpParameters(mediaSection);
+          self._pendingOffer[sdpMLineIndex].localCapabilities = caps;
+        });
+        this.transceivers = this._pendingOffer;
+        delete this._pendingOffer;
+      }
+    } else if (description.type === 'answer') {
+      sections = SDPUtils.splitSections(self.remoteDescription.sdp);
+      sessionpart = sections.shift();
+      var isIceLite = SDPUtils.matchPrefix(sessionpart,
+          'a=ice-lite').length > 0;
+      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);
+
+          // Start the RTCRtpSender. The RTCRtpReceiver for this
+          // transceiver has already been started in setRemoteDescription.
+          self._transceive(transceiver,
+              params.codecs.length > 0,
+              false);
+        }
+      });
+    }
+
+    this.localDescription = {
+      type: description.type,
+      sdp: description.sdp
+    };
+    switch (description.type) {
+      case 'offer':
+        this._updateSignalingState('have-local-offer');
+        break;
+      case 'answer':
+        this._updateSignalingState('stable');
+        break;
+      default:
+        throw new TypeError('unsupported type "' + description.type +
+            '"');
+    }
+
+    // If a success callback was provided, emit ICE candidates after it
+    // has been executed. Otherwise, emit callback after the Promise is
+    // resolved.
+    var hasCallback = arguments.length > 1 &&
+      typeof arguments[1] === 'function';
+    if (hasCallback) {
+      var cb = arguments[1];
+      window.setTimeout(function() {
+        cb();
+        if (self.iceGatheringState === 'new') {
+          self.iceGatheringState = 'gathering';
+          self._emitGatheringStateChange();
+        }
+        self._emitBufferedCandidates();
+      }, 0);
+    }
+    var p = Promise.resolve();
+    p.then(function() {
+      if (!hasCallback) {
+        if (self.iceGatheringState === 'new') {
+          self.iceGatheringState = 'gathering';
+          self._emitGatheringStateChange();
+        }
+        // Usually candidates will be emitted earlier.
+        window.setTimeout(self._emitBufferedCandidates.bind(self), 500);
+      }
+    });
+    return p;
+  };
+
+  RTCPeerConnection.prototype.setRemoteDescription = function(description) {
+    var self = this;
+
+    if (!isActionAllowedInSignalingState('setRemoteDescription',
+        description.type, this.signalingState)) {
+      var e = new Error('Can not set remote ' + description.type +
+          ' in state ' + this.signalingState);
+      e.name = 'InvalidStateError';
+      if (arguments.length > 2 && typeof arguments[2] === 'function') {
+        window.setTimeout(arguments[2], 0, e);
+      }
+      return Promise.reject(e);
+    }
+
+    var streams = {};
+    var receiverList = [];
+    var sections = SDPUtils.splitSections(description.sdp);
+    var sessionpart = sections.shift();
+    var isIceLite = SDPUtils.matchPrefix(sessionpart,
+        'a=ice-lite').length > 0;
+    var usingBundle = SDPUtils.matchPrefix(sessionpart,
+        'a=group:BUNDLE ').length > 0;
+    this.usingBundle = usingBundle;
+    var iceOptions = SDPUtils.matchPrefix(sessionpart,
+        'a=ice-options:')[0];
+    if (iceOptions) {
+      this.canTrickleIceCandidates = iceOptions.substr(14).split(' ')
+          .indexOf('trickle') >= 0;
+    } else {
+      this.canTrickleIceCandidates = false;
+    }
+
+    sections.forEach(function(mediaSection, sdpMLineIndex) {
+      var lines = SDPUtils.splitLines(mediaSection);
+      var kind = SDPUtils.getKind(mediaSection);
+      var rejected = SDPUtils.isRejected(mediaSection);
+      var protocol = lines[0].substr(2).split(' ')[2];
+
+      var direction = SDPUtils.getDirection(mediaSection, sessionpart);
+      var remoteMsid = SDPUtils.parseMsid(mediaSection);
+
+      var mid = SDPUtils.getMid(mediaSection) || SDPUtils.generateIdentifier();
+
+      // Reject datachannels which are not implemented yet.
+      if (kind === 'application' && protocol === 'DTLS/SCTP') {
+        self.transceivers[sdpMLineIndex] = {
+          mid: mid,
+          isDatachannel: true
+        };
+        return;
+      }
+
+      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);
+          })
+          .filter(function(cand) {
+            return cand.component === '1' || cand.component === 1;
+          });
+
+      // Check if we can use BUNDLE and dispose transports.
+      if ((description.type === 'offer' || description.type === 'answer') &&
+          !rejected && usingBundle && sdpMLineIndex > 0 &&
+          self.transceivers[sdpMLineIndex]) {
+        self._disposeIceAndDtlsTransports(sdpMLineIndex);
+        self.transceivers[sdpMLineIndex].iceGatherer =
+            self.transceivers[0].iceGatherer;
+        self.transceivers[sdpMLineIndex].iceTransport =
+            self.transceivers[0].iceTransport;
+        self.transceivers[sdpMLineIndex].dtlsTransport =
+            self.transceivers[0].dtlsTransport;
+        if (self.transceivers[sdpMLineIndex].rtpSender) {
+          self.transceivers[sdpMLineIndex].rtpSender.setTransport(
+              self.transceivers[0].dtlsTransport);
+        }
+        if (self.transceivers[sdpMLineIndex].rtpReceiver) {
+          self.transceivers[sdpMLineIndex].rtpReceiver.setTransport(
+              self.transceivers[0].dtlsTransport);
+        }
+      }
+      if (description.type === 'offer' && !rejected) {
+        transceiver = self.transceivers[sdpMLineIndex] ||
+            self._createTransceiver(kind);
+        transceiver.mid = mid;
+
+        if (!transceiver.iceGatherer) {
+          transceiver.iceGatherer = usingBundle && sdpMLineIndex > 0 ?
+              self.transceivers[0].iceGatherer :
+              self._createIceGatherer(mid, sdpMLineIndex);
+        }
+
+        if (isComplete && (!usingBundle || sdpMLineIndex === 0)) {
+          transceiver.iceTransport.setRemoteCandidates(cands);
+        }
+
+        localCapabilities = window.RTCRtpReceiver.getCapabilities(kind);
+
+        // filter RTX until additional stuff needed for RTX is implemented
+        // in adapter.js
+        if (edgeVersion < 15019) {
+          localCapabilities.codecs = localCapabilities.codecs.filter(
+              function(codec) {
+                return codec.name !== 'rtx';
+              });
+        }
+
+        sendEncodingParameters = [{
+          ssrc: (2 * sdpMLineIndex + 2) * 1001
+        }];
+
+        if (direction === 'sendrecv' || direction === 'sendonly') {
+          rtpReceiver = new window.RTCRtpReceiver(transceiver.dtlsTransport,
+              kind);
+
+          track = rtpReceiver.track;
+          // FIXME: does not work with Plan B.
+          if (remoteMsid) {
+            if (!streams[remoteMsid.stream]) {
+              streams[remoteMsid.stream] = new window.MediaStream();
+              Object.defineProperty(streams[remoteMsid.stream], 'id', {
+                get: function() {
+                  return remoteMsid.stream;
+                }
+              });
+            }
+            Object.defineProperty(track, 'id', {
+              get: function() {
+                return remoteMsid.track;
+              }
+            });
+            streams[remoteMsid.stream].addTrack(track);
+            receiverList.push([track, rtpReceiver,
+              streams[remoteMsid.stream]]);
+          } else {
+            if (!streams.default) {
+              streams.default = new window.MediaStream();
+            }
+            streams.default.addTrack(track);
+            receiverList.push([track, rtpReceiver, streams.default]);
+          }
+        }
+
+        transceiver.localCapabilities = localCapabilities;
+        transceiver.remoteCapabilities = remoteCapabilities;
+        transceiver.rtpReceiver = rtpReceiver;
+        transceiver.rtcpParameters = rtcpParameters;
+        transceiver.sendEncodingParameters = sendEncodingParameters;
+        transceiver.recvEncodingParameters = recvEncodingParameters;
+
+        // Start the RTCRtpReceiver now. The RTPSender is started in
+        // setLocalDescription.
+        self._transceive(self.transceivers[sdpMLineIndex],
+            false,
+            direction === 'sendrecv' || direction === 'sendonly');
+      } else if (description.type === 'answer' && !rejected) {
+        transceiver = self.transceivers[sdpMLineIndex];
+        iceGatherer = transceiver.iceGatherer;
+        iceTransport = transceiver.iceTransport;
+        dtlsTransport = transceiver.dtlsTransport;
+        rtpReceiver = transceiver.rtpReceiver;
+        sendEncodingParameters = transceiver.sendEncodingParameters;
+        localCapabilities = transceiver.localCapabilities;
+
+        self.transceivers[sdpMLineIndex].recvEncodingParameters =
+            recvEncodingParameters;
+        self.transceivers[sdpMLineIndex].remoteCapabilities =
+            remoteCapabilities;
+        self.transceivers[sdpMLineIndex].rtcpParameters = rtcpParameters;
+
+        if ((isIceLite || isComplete) && cands.length) {
+          iceTransport.setRemoteCandidates(cands);
+        }
+        if (!usingBundle || sdpMLineIndex === 0) {
+          iceTransport.start(iceGatherer, remoteIceParameters,
+              'controlling');
+          dtlsTransport.start(remoteDtlsParameters);
+        }
+
+        self._transceive(transceiver,
+            direction === 'sendrecv' || direction === 'recvonly',
+            direction === 'sendrecv' || direction === 'sendonly');
+
+        if (rtpReceiver &&
+            (direction === 'sendrecv' || direction === 'sendonly')) {
+          track = rtpReceiver.track;
+          if (remoteMsid) {
+            if (!streams[remoteMsid.stream]) {
+              streams[remoteMsid.stream] = new window.MediaStream();
+            }
+            streams[remoteMsid.stream].addTrack(track);
+            receiverList.push([track, rtpReceiver, streams[remoteMsid.stream]]);
+          } else {
+            if (!streams.default) {
+              streams.default = new window.MediaStream();
+            }
+            streams.default.addTrack(track);
+            receiverList.push([track, rtpReceiver, streams.default]);
+          }
+        } else {
+          // FIXME: actually the receiver should be created later.
+          delete transceiver.rtpReceiver;
+        }
+      }
+    });
+
+    this.remoteDescription = {
+      type: description.type,
+      sdp: description.sdp
+    };
+    switch (description.type) {
+      case 'offer':
+        this._updateSignalingState('have-remote-offer');
+        break;
+      case 'answer':
+        this._updateSignalingState('stable');
+        break;
+      default:
+        throw new TypeError('unsupported type "' + description.type +
+            '"');
+    }
+    Object.keys(streams).forEach(function(sid) {
+      var stream = streams[sid];
+      if (stream.getTracks().length) {
+        self.remoteStreams.push(stream);
+        var event = new Event('addstream');
+        event.stream = stream;
+        self.dispatchEvent(event);
+        if (self.onaddstream !== null) {
+          window.setTimeout(function() {
+            self.onaddstream(event);
+          }, 0);
+        }
+
+        receiverList.forEach(function(item) {
+          var track = item[0];
+          var receiver = item[1];
+          if (stream.id !== item[2].id) {
+            return;
+          }
+          var trackEvent = new Event('track');
+          trackEvent.track = track;
+          trackEvent.receiver = receiver;
+          trackEvent.streams = [stream];
+          self.dispatchEvent(trackEvent);
+          if (self.ontrack !== null) {
+            window.setTimeout(function() {
+              self.ontrack(trackEvent);
+            }, 0);
+          }
+        });
+      }
+    });
+
+    // check whether addIceCandidate({}) was called within four seconds after
+    // setRemoteDescription.
+    window.setTimeout(function() {
+      if (!(self && self.transceivers)) {
+        return;
+      }
+      self.transceivers.forEach(function(transceiver) {
+        if (transceiver.iceTransport &&
+            transceiver.iceTransport.state === 'new' &&
+            transceiver.iceTransport.getRemoteCandidates().length > 0) {
+          console.warn('Timeout for addRemoteCandidate. Consider sending ' +
+              'an end-of-candidates notification');
+          transceiver.iceTransport.addRemoteCandidate({});
+        }
+      });
+    }, 4000);
+
+    if (arguments.length > 1 && typeof arguments[1] === 'function') {
+      window.setTimeout(arguments[1], 0);
+    }
+    return Promise.resolve();
+  };
+
+  RTCPeerConnection.prototype.close = function() {
+    this.transceivers.forEach(function(transceiver) {
+      /* not yet
+      if (transceiver.iceGatherer) {
+        transceiver.iceGatherer.close();
+      }
+      */
+      if (transceiver.iceTransport) {
+        transceiver.iceTransport.stop();
+      }
+      if (transceiver.dtlsTransport) {
+        transceiver.dtlsTransport.stop();
+      }
+      if (transceiver.rtpSender) {
+        transceiver.rtpSender.stop();
+      }
+      if (transceiver.rtpReceiver) {
+        transceiver.rtpReceiver.stop();
+      }
+    });
+    // FIXME: clean up tracks, local streams, remote streams, etc
+    this._updateSignalingState('closed');
+  };
+
+  // Update the signaling state.
+  RTCPeerConnection.prototype._updateSignalingState = function(newState) {
+    this.signalingState = newState;
+    var event = new Event('signalingstatechange');
+    this.dispatchEvent(event);
+    if (this.onsignalingstatechange !== null) {
+      this.onsignalingstatechange(event);
+    }
+  };
+
+  // Determine whether to fire the negotiationneeded event.
+  RTCPeerConnection.prototype._maybeFireNegotiationNeeded = function() {
+    var self = this;
+    if (this.signalingState !== 'stable' || this.needNegotiation === true) {
+      return;
+    }
+    this.needNegotiation = true;
+    window.setTimeout(function() {
+      if (self.needNegotiation === false) {
+        return;
+      }
+      self.needNegotiation = false;
+      var event = new Event('negotiationneeded');
+      self.dispatchEvent(event);
+      if (self.onnegotiationneeded !== null) {
+        self.onnegotiationneeded(event);
+      }
+    }, 0);
+  };
+
+  // Update the connection state.
+  RTCPeerConnection.prototype._updateConnectionState = function() {
+    var self = this;
+    var newState;
+    var states = {
+      'new': 0,
+      closed: 0,
+      connecting: 0,
+      checking: 0,
+      connected: 0,
+      completed: 0,
+      disconnected: 0,
+      failed: 0
+    };
+    this.transceivers.forEach(function(transceiver) {
+      states[transceiver.iceTransport.state]++;
+      states[transceiver.dtlsTransport.state]++;
+    });
+    // ICETransport.completed and connected are the same for this purpose.
+    states.connected += states.completed;
+
+    newState = 'new';
+    if (states.failed > 0) {
+      newState = 'failed';
+    } else if (states.connecting > 0 || states.checking > 0) {
+      newState = 'connecting';
+    } else if (states.disconnected > 0) {
+      newState = 'disconnected';
+    } else if (states.new > 0) {
+      newState = 'new';
+    } else if (states.connected > 0 || states.completed > 0) {
+      newState = 'connected';
+    }
+
+    if (newState !== self.iceConnectionState) {
+      self.iceConnectionState = newState;
+      var event = new Event('iceconnectionstatechange');
+      this.dispatchEvent(event);
+      if (this.oniceconnectionstatechange !== null) {
+        this.oniceconnectionstatechange(event);
+      }
+    }
+  };
+
+  RTCPeerConnection.prototype.createOffer = function() {
+    var self = this;
+    if (this._pendingOffer) {
+      throw new Error('createOffer called while there is a pending offer.');
+    }
+    var offerOptions;
+    if (arguments.length === 1 && typeof arguments[0] !== 'function') {
+      offerOptions = arguments[0];
+    } else if (arguments.length === 3) {
+      offerOptions = arguments[2];
+    }
+
+    var numAudioTracks = this.transceivers.filter(function(t) {
+      return t.kind === 'audio';
+    }).length;
+    var numVideoTracks = this.transceivers.filter(function(t) {
+      return t.kind === 'video';
+    }).length;
+
+    // Determine number of audio and video tracks we need to send/recv.
+    if (offerOptions) {
+      // Reject Chrome legacy constraints.
+      if (offerOptions.mandatory || offerOptions.optional) {
+        throw new TypeError(
+            'Legacy mandatory/optional constraints not supported.');
+      }
+      if (offerOptions.offerToReceiveAudio !== undefined) {
+        if (offerOptions.offerToReceiveAudio === true) {
+          numAudioTracks = 1;
+        } else if (offerOptions.offerToReceiveAudio === false) {
+          numAudioTracks = 0;
+        } else {
+          numAudioTracks = offerOptions.offerToReceiveAudio;
+        }
+      }
+      if (offerOptions.offerToReceiveVideo !== undefined) {
+        if (offerOptions.offerToReceiveVideo === true) {
+          numVideoTracks = 1;
+        } else if (offerOptions.offerToReceiveVideo === false) {
+          numVideoTracks = 0;
+        } else {
+          numVideoTracks = offerOptions.offerToReceiveVideo;
+        }
+      }
+    }
+
+    this.transceivers.forEach(function(transceiver) {
+      if (transceiver.kind === 'audio') {
+        numAudioTracks--;
+        if (numAudioTracks < 0) {
+          transceiver.wantReceive = false;
+        }
+      } else if (transceiver.kind === 'video') {
+        numVideoTracks--;
+        if (numVideoTracks < 0) {
+          transceiver.wantReceive = false;
+        }
+      }
+    });
+
+    // Create M-lines for recvonly streams.
+    while (numAudioTracks > 0 || numVideoTracks > 0) {
+      if (numAudioTracks > 0) {
+        this._createTransceiver('audio');
+        numAudioTracks--;
+      }
+      if (numVideoTracks > 0) {
+        this._createTransceiver('video');
+        numVideoTracks--;
+      }
+    }
+    // reorder tracks
+    var transceivers = sortTracks(this.transceivers);
+
+    var sdp = SDPUtils.writeSessionBoilerplate(this._sdpSessionId);
+    transceivers.forEach(function(transceiver, sdpMLineIndex) {
+      // For each track, create an ice gatherer, ice transport,
+      // dtls transport, potentially rtpsender and rtpreceiver.
+      var track = transceiver.track;
+      var kind = transceiver.kind;
+      var mid = SDPUtils.generateIdentifier();
+      transceiver.mid = mid;
+
+      if (!transceiver.iceGatherer) {
+        transceiver.iceGatherer = self.usingBundle && sdpMLineIndex > 0 ?
+            transceivers[0].iceGatherer :
+            self._createIceGatherer(mid, sdpMLineIndex);
+      }
+
+      var localCapabilities = window.RTCRtpSender.getCapabilities(kind);
+      // filter RTX until additional stuff needed for RTX is implemented
+      // in adapter.js
+      if (edgeVersion < 15019) {
+        localCapabilities.codecs = localCapabilities.codecs.filter(
+            function(codec) {
+              return codec.name !== 'rtx';
+            });
+      }
+      localCapabilities.codecs.forEach(function(codec) {
+        // work around https://bugs.chromium.org/p/webrtc/issues/detail?id=6552
+        // by adding level-asymmetry-allowed=1
+        if (codec.name === 'H264' &&
+            codec.parameters['level-asymmetry-allowed'] === undefined) {
+          codec.parameters['level-asymmetry-allowed'] = '1';
+        }
+      });
+
+      // generate an ssrc now, to be used later in rtpSender.send
+      var sendEncodingParameters = [{
+        ssrc: (2 * sdpMLineIndex + 1) * 1001
+      }];
+      if (track) {
+        // add RTX
+        if (edgeVersion >= 15019 && kind === 'video') {
+          sendEncodingParameters[0].rtx = {
+            ssrc: (2 * sdpMLineIndex + 1) * 1001 + 1
+          };
+        }
+      }
+
+      if (transceiver.wantReceive) {
+        transceiver.rtpReceiver = new window.RTCRtpReceiver(
+          transceiver.dtlsTransport,
+          kind
+        );
+      }
+
+      transceiver.localCapabilities = localCapabilities;
+      transceiver.sendEncodingParameters = sendEncodingParameters;
+    });
+
+    // always offer BUNDLE and dispose on return if not supported.
+    if (this._config.bundlePolicy !== 'max-compat') {
+      sdp += 'a=group:BUNDLE ' + transceivers.map(function(t) {
+        return t.mid;
+      }).join(' ') + '\r\n';
+    }
+    sdp += 'a=ice-options:trickle\r\n';
+
+    transceivers.forEach(function(transceiver, sdpMLineIndex) {
+      sdp += SDPUtils.writeMediaSection(transceiver,
+          transceiver.localCapabilities, 'offer', transceiver.stream);
+      sdp += 'a=rtcp-rsize\r\n';
+    });
+
+    this._pendingOffer = transceivers;
+    var desc = new window.RTCSessionDescription({
+      type: 'offer',
+      sdp: sdp
+    });
+    if (arguments.length && typeof arguments[0] === 'function') {
+      window.setTimeout(arguments[0], 0, desc);
+    }
+    return Promise.resolve(desc);
+  };
+
+  RTCPeerConnection.prototype.createAnswer = function() {
+    var sdp = SDPUtils.writeSessionBoilerplate(this._sdpSessionId);
+    if (this.usingBundle) {
+      sdp += 'a=group:BUNDLE ' + this.transceivers.map(function(t) {
+        return t.mid;
+      }).join(' ') + '\r\n';
+    }
+    this.transceivers.forEach(function(transceiver, sdpMLineIndex) {
+      if (transceiver.isDatachannel) {
+        sdp += 'm=application 0 DTLS/SCTP 5000\r\n' +
+            'c=IN IP4 0.0.0.0\r\n' +
+            'a=mid:' + transceiver.mid + '\r\n';
+        return;
+      }
+
+      // FIXME: look at direction.
+      if (transceiver.stream) {
+        var localTrack;
+        if (transceiver.kind === 'audio') {
+          localTrack = transceiver.stream.getAudioTracks()[0];
+        } else if (transceiver.kind === 'video') {
+          localTrack = transceiver.stream.getVideoTracks()[0];
+        }
+        if (localTrack) {
+          // add RTX
+          if (edgeVersion >= 15019 && transceiver.kind === 'video') {
+            transceiver.sendEncodingParameters[0].rtx = {
+              ssrc: (2 * sdpMLineIndex + 2) * 1001 + 1
+            };
+          }
+        }
+      }
+
+      // Calculate intersection of capabilities.
+      var commonCapabilities = getCommonCapabilities(
+          transceiver.localCapabilities,
+          transceiver.remoteCapabilities);
+
+      var hasRtx = commonCapabilities.codecs.filter(function(c) {
+        return c.name.toLowerCase() === 'rtx';
+      }).length;
+      if (!hasRtx && transceiver.sendEncodingParameters[0].rtx) {
+        delete transceiver.sendEncodingParameters[0].rtx;
+      }
+
+      sdp += SDPUtils.writeMediaSection(transceiver, commonCapabilities,
+          'answer', transceiver.stream);
+      if (transceiver.rtcpParameters &&
+          transceiver.rtcpParameters.reducedSize) {
+        sdp += 'a=rtcp-rsize\r\n';
+      }
+    });
+
+    var desc = new window.RTCSessionDescription({
+      type: 'answer',
+      sdp: sdp
+    });
+    if (arguments.length && typeof arguments[0] === 'function') {
+      window.setTimeout(arguments[0], 0, desc);
+    }
+    return Promise.resolve(desc);
+  };
+
+  RTCPeerConnection.prototype.addIceCandidate = function(candidate) {
+    if (!candidate) {
+      for (var j = 0; j < this.transceivers.length; j++) {
+        this.transceivers[j].iceTransport.addRemoteCandidate({});
+        if (this.usingBundle) {
+          return Promise.resolve();
+        }
+      }
+    } else {
+      var mLineIndex = candidate.sdpMLineIndex;
+      if (candidate.sdpMid) {
+        for (var i = 0; i < this.transceivers.length; i++) {
+          if (this.transceivers[i].mid === candidate.sdpMid) {
+            mLineIndex = i;
+            break;
+          }
+        }
+      }
+      var transceiver = this.transceivers[mLineIndex];
+      if (transceiver) {
+        var cand = Object.keys(candidate.candidate).length > 0 ?
+            SDPUtils.parseCandidate(candidate.candidate) : {};
+        // Ignore Chrome's invalid candidates since Edge does not like them.
+        if (cand.protocol === 'tcp' && (cand.port === 0 || cand.port === 9)) {
+          return Promise.resolve();
+        }
+        // Ignore RTCP candidates, we assume RTCP-MUX.
+        if (cand.component &&
+            !(cand.component === '1' || cand.component === 1)) {
+          return Promise.resolve();
+        }
+        transceiver.iceTransport.addRemoteCandidate(cand);
+
+        // update the remoteDescription.
+        var sections = SDPUtils.splitSections(this.remoteDescription.sdp);
+        sections[mLineIndex + 1] += (cand.type ? candidate.candidate.trim()
+            : 'a=end-of-candidates') + '\r\n';
+        this.remoteDescription.sdp = sections.join('');
+      }
+    }
+    if (arguments.length > 1 && typeof arguments[1] === 'function') {
+      window.setTimeout(arguments[1], 0);
+    }
+    return Promise.resolve();
+  };
+
+  RTCPeerConnection.prototype.getStats = function() {
+    var promises = [];
+    this.transceivers.forEach(function(transceiver) {
+      ['rtpSender', 'rtpReceiver', 'iceGatherer', 'iceTransport',
+        'dtlsTransport'].forEach(function(method) {
+          if (transceiver[method]) {
+            promises.push(transceiver[method].getStats());
+          }
+        });
+    });
+    var cb = arguments.length > 1 && typeof arguments[1] === 'function' &&
+        arguments[1];
+    var fixStatsType = function(stat) {
+      return {
+        inboundrtp: 'inbound-rtp',
+        outboundrtp: 'outbound-rtp',
+        candidatepair: 'candidate-pair',
+        localcandidate: 'local-candidate',
+        remotecandidate: 'remote-candidate'
+      }[stat.type] || stat.type;
+    };
+    return new Promise(function(resolve) {
+      // shim getStats with maplike support
+      var results = new Map();
+      Promise.all(promises).then(function(res) {
+        res.forEach(function(result) {
+          Object.keys(result).forEach(function(id) {
+            result[id].type = fixStatsType(result[id]);
+            results.set(id, result[id]);
+          });
+        });
+        if (cb) {
+          window.setTimeout(cb, 0, results);
+        }
+        resolve(results);
+      });
+    });
+  };
+  return RTCPeerConnection;
+};
+
+},{"sdp":1}],9:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+
+var utils = require('../utils');
+
+var firefoxShim = {
+  shimOnTrack: function(window) {
+    if (typeof window === 'object' && window.RTCPeerConnection && !('ontrack' in
+        window.RTCPeerConnection.prototype)) {
+      Object.defineProperty(window.RTCPeerConnection.prototype, 'ontrack', {
+        get: function() {
+          return this._ontrack;
+        },
+        set: function(f) {
+          if (this._ontrack) {
+            this.removeEventListener('track', this._ontrack);
+            this.removeEventListener('addstream', this._ontrackpoly);
+          }
+          this.addEventListener('track', this._ontrack = f);
+          this.addEventListener('addstream', this._ontrackpoly = function(e) {
+            e.stream.getTracks().forEach(function(track) {
+              var event = new Event('track');
+              event.track = track;
+              event.receiver = {track: track};
+              event.streams = [e.stream];
+              this.dispatchEvent(event);
+            }.bind(this));
+          }.bind(this));
+        }
+      });
+    }
+  },
+
+  shimSourceObject: function(window) {
+    // Firefox has supported mozSrcObject since FF22, unprefixed in 42.
+    if (typeof window === 'object') {
+      if (window.HTMLMediaElement &&
+        !('srcObject' in window.HTMLMediaElement.prototype)) {
+        // Shim the srcObject property, once, when HTMLMediaElement is found.
+        Object.defineProperty(window.HTMLMediaElement.prototype, 'srcObject', {
+          get: function() {
+            return this.mozSrcObject;
+          },
+          set: function(stream) {
+            this.mozSrcObject = stream;
+          }
+        });
+      }
+    }
+  },
+
+  shimPeerConnection: function(window) {
+    var browserDetails = utils.detectBrowser(window);
+
+    if (typeof window !== 'object' || !(window.RTCPeerConnection ||
+        window.mozRTCPeerConnection)) {
+      return; // probably media.peerconnection.enabled=false in about:config
+    }
+    // The RTCPeerConnection object.
+    if (!window.RTCPeerConnection) {
+      window.RTCPeerConnection = function(pcConfig, pcConstraints) {
+        if (browserDetails.version < 38) {
+          // .urls is not supported in FF < 38.
+          // create RTCIceServers with a single url.
+          if (pcConfig && pcConfig.iceServers) {
+            var newIceServers = [];
+            for (var i = 0; i < pcConfig.iceServers.length; i++) {
+              var server = pcConfig.iceServers[i];
+              if (server.hasOwnProperty('urls')) {
+                for (var j = 0; j < server.urls.length; j++) {
+                  var newServer = {
+                    url: server.urls[j]
+                  };
+                  if (server.urls[j].indexOf('turn') === 0) {
+                    newServer.username = server.username;
+                    newServer.credential = server.credential;
+                  }
+                  newIceServers.push(newServer);
+                }
+              } else {
+                newIceServers.push(pcConfig.iceServers[i]);
+              }
+            }
+            pcConfig.iceServers = newIceServers;
+          }
+        }
+        return new window.mozRTCPeerConnection(pcConfig, pcConstraints);
+      };
+      window.RTCPeerConnection.prototype =
+          window.mozRTCPeerConnection.prototype;
+
+      // wrap static methods. Currently just generateCertificate.
+      if (window.mozRTCPeerConnection.generateCertificate) {
+        Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
+          get: function() {
+            return window.mozRTCPeerConnection.generateCertificate;
+          }
+        });
+      }
+
+      window.RTCSessionDescription = window.mozRTCSessionDescription;
+      window.RTCIceCandidate = window.mozRTCIceCandidate;
+    }
+
+    // shim away need for obsolete RTCIceCandidate/RTCSessionDescription.
+    ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
+        .forEach(function(method) {
+          var nativeMethod = window.RTCPeerConnection.prototype[method];
+          window.RTCPeerConnection.prototype[method] = function() {
+            arguments[0] = new ((method === 'addIceCandidate') ?
+                window.RTCIceCandidate :
+                window.RTCSessionDescription)(arguments[0]);
+            return nativeMethod.apply(this, arguments);
+          };
+        });
+
+    // support for addIceCandidate(null or undefined)
+    var nativeAddIceCandidate =
+        window.RTCPeerConnection.prototype.addIceCandidate;
+    window.RTCPeerConnection.prototype.addIceCandidate = function() {
+      if (!arguments[0]) {
+        if (arguments[1]) {
+          arguments[1].apply(null);
+        }
+        return Promise.resolve();
+      }
+      return nativeAddIceCandidate.apply(this, arguments);
+    };
+
+    // shim getStats with maplike support
+    var makeMapStats = function(stats) {
+      var map = new Map();
+      Object.keys(stats).forEach(function(key) {
+        map.set(key, stats[key]);
+        map[key] = stats[key];
+      });
+      return map;
+    };
+
+    var modernStatsTypes = {
+      inboundrtp: 'inbound-rtp',
+      outboundrtp: 'outbound-rtp',
+      candidatepair: 'candidate-pair',
+      localcandidate: 'local-candidate',
+      remotecandidate: 'remote-candidate'
+    };
+
+    var nativeGetStats = window.RTCPeerConnection.prototype.getStats;
+    window.RTCPeerConnection.prototype.getStats = function(
+      selector,
+      onSucc,
+      onErr
+    ) {
+      return nativeGetStats.apply(this, [selector || null])
+        .then(function(stats) {
+          if (browserDetails.version < 48) {
+            stats = makeMapStats(stats);
+          }
+          if (browserDetails.version < 53 && !onSucc) {
+            // Shim only promise getStats with spec-hyphens in type names
+            // Leave callback version alone; misc old uses of forEach before Map
+            try {
+              stats.forEach(function(stat) {
+                stat.type = modernStatsTypes[stat.type] || stat.type;
+              });
+            } catch (e) {
+              if (e.name !== 'TypeError') {
+                throw e;
+              }
+              // Avoid TypeError: "type" is read-only, in old versions. 34-43ish
+              stats.forEach(function(stat, i) {
+                stats.set(i, Object.assign({}, stat, {
+                  type: modernStatsTypes[stat.type] || stat.type
+                }));
+              });
+            }
+          }
+          return stats;
+        })
+        .then(onSucc, onErr);
+    };
+  }
+};
+
+// Expose public methods.
+module.exports = {
+  shimOnTrack: firefoxShim.shimOnTrack,
+  shimSourceObject: firefoxShim.shimSourceObject,
+  shimPeerConnection: firefoxShim.shimPeerConnection,
+  shimGetUserMedia: require('./getusermedia')
+};
+
+},{"../utils":12,"./getusermedia":10}],10:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+
+var utils = require('../utils');
+var logging = utils.log;
+
+// Expose public methods.
+module.exports = function(window) {
+  var browserDetails = utils.detectBrowser(window);
+  var navigator = window && window.navigator;
+  var MediaStreamTrack = window && window.MediaStreamTrack;
+
+  var shimError_ = function(e) {
+    return {
+      name: {
+        InternalError: 'NotReadableError',
+        NotSupportedError: 'TypeError',
+        PermissionDeniedError: 'NotAllowedError',
+        SecurityError: 'NotAllowedError'
+      }[e.name] || e.name,
+      message: {
+        'The operation is insecure.': 'The request is not allowed by the ' +
+        'user agent or the platform in the current context.'
+      }[e.message] || e.message,
+      constraint: e.constraint,
+      toString: function() {
+        return this.name + (this.message && ': ') + this.message;
+      }
+    };
+  };
+
+  // getUserMedia constraints shim.
+  var getUserMedia_ = function(constraints, onSuccess, onError) {
+    var constraintsToFF37_ = function(c) {
+      if (typeof c !== 'object' || c.require) {
+        return c;
+      }
+      var require = [];
+      Object.keys(c).forEach(function(key) {
+        if (key === 'require' || key === 'advanced' || key === 'mediaSource') {
+          return;
+        }
+        var r = c[key] = (typeof c[key] === 'object') ?
+            c[key] : {ideal: c[key]};
+        if (r.min !== undefined ||
+            r.max !== undefined || r.exact !== undefined) {
+          require.push(key);
+        }
+        if (r.exact !== undefined) {
+          if (typeof r.exact === 'number') {
+            r. min = r.max = r.exact;
+          } else {
+            c[key] = r.exact;
+          }
+          delete r.exact;
+        }
+        if (r.ideal !== undefined) {
+          c.advanced = c.advanced || [];
+          var oc = {};
+          if (typeof r.ideal === 'number') {
+            oc[key] = {min: r.ideal, max: r.ideal};
+          } else {
+            oc[key] = r.ideal;
+          }
+          c.advanced.push(oc);
+          delete r.ideal;
+          if (!Object.keys(r).length) {
+            delete c[key];
+          }
+        }
+      });
+      if (require.length) {
+        c.require = require;
+      }
+      return c;
+    };
+    constraints = JSON.parse(JSON.stringify(constraints));
+    if (browserDetails.version < 38) {
+      logging('spec: ' + JSON.stringify(constraints));
+      if (constraints.audio) {
+        constraints.audio = constraintsToFF37_(constraints.audio);
+      }
+      if (constraints.video) {
+        constraints.video = constraintsToFF37_(constraints.video);
+      }
+      logging('ff37: ' + JSON.stringify(constraints));
+    }
+    return navigator.mozGetUserMedia(constraints, onSuccess, function(e) {
+      onError(shimError_(e));
+    });
+  };
+
+  // Returns the result of getUserMedia as a Promise.
+  var getUserMediaPromise_ = function(constraints) {
+    return new Promise(function(resolve, reject) {
+      getUserMedia_(constraints, resolve, reject);
+    });
+  };
+
+  // Shim for mediaDevices on older versions.
+  if (!navigator.mediaDevices) {
+    navigator.mediaDevices = {getUserMedia: getUserMediaPromise_,
+      addEventListener: function() { },
+      removeEventListener: function() { }
+    };
+  }
+  navigator.mediaDevices.enumerateDevices =
+      navigator.mediaDevices.enumerateDevices || function() {
+        return new Promise(function(resolve) {
+          var infos = [
+            {kind: 'audioinput', deviceId: 'default', label: '', groupId: ''},
+            {kind: 'videoinput', deviceId: 'default', label: '', groupId: ''}
+          ];
+          resolve(infos);
+        });
+      };
+
+  if (browserDetails.version < 41) {
+    // Work around http://bugzil.la/1169665
+    var orgEnumerateDevices =
+        navigator.mediaDevices.enumerateDevices.bind(navigator.mediaDevices);
+    navigator.mediaDevices.enumerateDevices = function() {
+      return orgEnumerateDevices().then(undefined, function(e) {
+        if (e.name === 'NotFoundError') {
+          return [];
+        }
+        throw e;
+      });
+    };
+  }
+  if (browserDetails.version < 49) {
+    var origGetUserMedia = navigator.mediaDevices.getUserMedia.
+        bind(navigator.mediaDevices);
+    navigator.mediaDevices.getUserMedia = function(c) {
+      return origGetUserMedia(c).then(function(stream) {
+        // Work around https://bugzil.la/802326
+        if (c.audio && !stream.getAudioTracks().length ||
+            c.video && !stream.getVideoTracks().length) {
+          stream.getTracks().forEach(function(track) {
+            track.stop();
+          });
+          throw new DOMException('The object can not be found here.',
+                                 'NotFoundError');
+        }
+        return stream;
+      }, function(e) {
+        return Promise.reject(shimError_(e));
+      });
+    };
+  }
+  if (!(browserDetails.version > 55 &&
+      'autoGainControl' in navigator.mediaDevices.getSupportedConstraints())) {
+    var remap = function(obj, a, b) {
+      if (a in obj && !(b in obj)) {
+        obj[b] = obj[a];
+        delete obj[a];
+      }
+    };
+
+    var nativeGetUserMedia = navigator.mediaDevices.getUserMedia.
+        bind(navigator.mediaDevices);
+    navigator.mediaDevices.getUserMedia = function(c) {
+      if (typeof c === 'object' && typeof c.audio === 'object') {
+        c = JSON.parse(JSON.stringify(c));
+        remap(c.audio, 'autoGainControl', 'mozAutoGainControl');
+        remap(c.audio, 'noiseSuppression', 'mozNoiseSuppression');
+      }
+      return nativeGetUserMedia(c);
+    };
+
+    if (MediaStreamTrack && MediaStreamTrack.prototype.getSettings) {
+      var nativeGetSettings = MediaStreamTrack.prototype.getSettings;
+      MediaStreamTrack.prototype.getSettings = function() {
+        var obj = nativeGetSettings.apply(this, arguments);
+        remap(obj, 'mozAutoGainControl', 'autoGainControl');
+        remap(obj, 'mozNoiseSuppression', 'noiseSuppression');
+        return obj;
+      };
+    }
+
+    if (MediaStreamTrack && MediaStreamTrack.prototype.applyConstraints) {
+      var nativeApplyConstraints = MediaStreamTrack.prototype.applyConstraints;
+      MediaStreamTrack.prototype.applyConstraints = function(c) {
+        if (this.kind === 'audio' && typeof c === 'object') {
+          c = JSON.parse(JSON.stringify(c));
+          remap(c, 'autoGainControl', 'mozAutoGainControl');
+          remap(c, 'noiseSuppression', 'mozNoiseSuppression');
+        }
+        return nativeApplyConstraints.apply(this, [c]);
+      };
+    }
+  }
+  navigator.getUserMedia = function(constraints, onSuccess, onError) {
+    if (browserDetails.version < 44) {
+      return getUserMedia_(constraints, onSuccess, onError);
+    }
+    // Replace Firefox 44+'s deprecation warning with unprefixed version.
+    console.warn('navigator.getUserMedia has been replaced by ' +
+                 'navigator.mediaDevices.getUserMedia');
+    navigator.mediaDevices.getUserMedia(constraints).then(onSuccess, onError);
+  };
+};
+
+},{"../utils":12}],11:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+'use strict';
+var utils = require('../utils');
+
+var safariShim = {
+  // TODO: DrAlex, should be here, double check against LayoutTests
+
+  // TODO: once the back-end for the mac port is done, add.
+  // TODO: check for webkitGTK+
+  // shimPeerConnection: function() { },
+
+  shimLocalStreamsAPI: function(window) {
+    if (typeof window !== 'object' || !window.RTCPeerConnection) {
+      return;
+    }
+    if (!('getLocalStreams' in window.RTCPeerConnection.prototype)) {
+      window.RTCPeerConnection.prototype.getLocalStreams = function() {
+        if (!this._localStreams) {
+          this._localStreams = [];
+        }
+        return this._localStreams;
+      };
+    }
+    if (!('getStreamById' in window.RTCPeerConnection.prototype)) {
+      window.RTCPeerConnection.prototype.getStreamById = function(id) {
+        var result = null;
+        if (this._localStreams) {
+          this._localStreams.forEach(function(stream) {
+            if (stream.id === id) {
+              result = stream;
+            }
+          });
+        }
+        if (this._remoteStreams) {
+          this._remoteStreams.forEach(function(stream) {
+            if (stream.id === id) {
+              result = stream;
+            }
+          });
+        }
+        return result;
+      };
+    }
+    if (!('addStream' in window.RTCPeerConnection.prototype)) {
+      var _addTrack = window.RTCPeerConnection.prototype.addTrack;
+      window.RTCPeerConnection.prototype.addStream = function(stream) {
+        if (!this._localStreams) {
+          this._localStreams = [];
+        }
+        if (this._localStreams.indexOf(stream) === -1) {
+          this._localStreams.push(stream);
+        }
+        var self = this;
+        stream.getTracks().forEach(function(track) {
+          _addTrack.call(self, track, stream);
+        });
+      };
+
+      window.RTCPeerConnection.prototype.addTrack = function(track, stream) {
+        if (stream) {
+          if (!this._localStreams) {
+            this._localStreams = [stream];
+          } else if (this._localStreams.indexOf(stream) === -1) {
+            this._localStreams.push(stream);
+          }
+        }
+        _addTrack.call(this, track, stream);
+      };
+    }
+    if (!('removeStream' in window.RTCPeerConnection.prototype)) {
+      window.RTCPeerConnection.prototype.removeStream = function(stream) {
+        if (!this._localStreams) {
+          this._localStreams = [];
+        }
+        var index = this._localStreams.indexOf(stream);
+        if (index === -1) {
+          return;
+        }
+        this._localStreams.splice(index, 1);
+        var self = this;
+        var tracks = stream.getTracks();
+        this.getSenders().forEach(function(sender) {
+          if (tracks.indexOf(sender.track) !== -1) {
+            self.removeTrack(sender);
+          }
+        });
+      };
+    }
+  },
+  shimRemoteStreamsAPI: function(window) {
+    if (typeof window !== 'object' || !window.RTCPeerConnection) {
+      return;
+    }
+    if (!('getRemoteStreams' in window.RTCPeerConnection.prototype)) {
+      window.RTCPeerConnection.prototype.getRemoteStreams = function() {
+        return this._remoteStreams ? this._remoteStreams : [];
+      };
+    }
+    if (!('onaddstream' in window.RTCPeerConnection.prototype)) {
+      Object.defineProperty(window.RTCPeerConnection.prototype, 'onaddstream', {
+        get: function() {
+          return this._onaddstream;
+        },
+        set: function(f) {
+          if (this._onaddstream) {
+            this.removeEventListener('addstream', this._onaddstream);
+            this.removeEventListener('track', this._onaddstreampoly);
+          }
+          this.addEventListener('addstream', this._onaddstream = f);
+          this.addEventListener('track', this._onaddstreampoly = function(e) {
+            var stream = e.streams[0];
+            if (!this._remoteStreams) {
+              this._remoteStreams = [];
+            }
+            if (this._remoteStreams.indexOf(stream) >= 0) {
+              return;
+            }
+            this._remoteStreams.push(stream);
+            var event = new Event('addstream');
+            event.stream = e.streams[0];
+            this.dispatchEvent(event);
+          }.bind(this));
+        }
+      });
+    }
+  },
+  shimCallbacksAPI: function(window) {
+    if (typeof window !== 'object' || !window.RTCPeerConnection) {
+      return;
+    }
+    var prototype = window.RTCPeerConnection.prototype;
+    var createOffer = prototype.createOffer;
+    var createAnswer = prototype.createAnswer;
+    var setLocalDescription = prototype.setLocalDescription;
+    var setRemoteDescription = prototype.setRemoteDescription;
+    var addIceCandidate = prototype.addIceCandidate;
+
+    prototype.createOffer = function(successCallback, failureCallback) {
+      var options = (arguments.length >= 2) ? arguments[2] : arguments[0];
+      var promise = createOffer.apply(this, [options]);
+      if (!failureCallback) {
+        return promise;
+      }
+      promise.then(successCallback, failureCallback);
+      return Promise.resolve();
+    };
+
+    prototype.createAnswer = function(successCallback, failureCallback) {
+      var options = (arguments.length >= 2) ? arguments[2] : arguments[0];
+      var promise = createAnswer.apply(this, [options]);
+      if (!failureCallback) {
+        return promise;
+      }
+      promise.then(successCallback, failureCallback);
+      return Promise.resolve();
+    };
+
+    var withCallback = function(description, successCallback, failureCallback) {
+      var promise = setLocalDescription.apply(this, [description]);
+      if (!failureCallback) {
+        return promise;
+      }
+      promise.then(successCallback, failureCallback);
+      return Promise.resolve();
+    };
+    prototype.setLocalDescription = withCallback;
+
+    withCallback = function(description, successCallback, failureCallback) {
+      var promise = setRemoteDescription.apply(this, [description]);
+      if (!failureCallback) {
+        return promise;
+      }
+      promise.then(successCallback, failureCallback);
+      return Promise.resolve();
+    };
+    prototype.setRemoteDescription = withCallback;
+
+    withCallback = function(candidate, successCallback, failureCallback) {
+      var promise = addIceCandidate.apply(this, [candidate]);
+      if (!failureCallback) {
+        return promise;
+      }
+      promise.then(successCallback, failureCallback);
+      return Promise.resolve();
+    };
+    prototype.addIceCandidate = withCallback;
+  },
+  shimGetUserMedia: function(window) {
+    var navigator = window && window.navigator;
+
+    if (!navigator.getUserMedia) {
+      if (navigator.webkitGetUserMedia) {
+        navigator.getUserMedia = navigator.webkitGetUserMedia.bind(navigator);
+      } else if (navigator.mediaDevices &&
+          navigator.mediaDevices.getUserMedia) {
+        navigator.getUserMedia = function(constraints, cb, errcb) {
+          navigator.mediaDevices.getUserMedia(constraints)
+          .then(cb, errcb);
+        }.bind(navigator);
+      }
+    }
+  },
+  shimRTCIceServerUrls: function(window) {
+    // migrate from non-spec RTCIceServer.url to RTCIceServer.urls
+    var OrigPeerConnection = window.RTCPeerConnection;
+    window.RTCPeerConnection = function(pcConfig, pcConstraints) {
+      if (pcConfig && pcConfig.iceServers) {
+        var newIceServers = [];
+        for (var i = 0; i < pcConfig.iceServers.length; i++) {
+          var server = pcConfig.iceServers[i];
+          if (!server.hasOwnProperty('urls') &&
+              server.hasOwnProperty('url')) {
+            utils.deprecated('RTCIceServer.url', 'RTCIceServer.urls');
+            server = JSON.parse(JSON.stringify(server));
+            server.urls = server.url;
+            delete server.url;
+            newIceServers.push(server);
+          } else {
+            newIceServers.push(pcConfig.iceServers[i]);
+          }
+        }
+        pcConfig.iceServers = newIceServers;
+      }
+      return new OrigPeerConnection(pcConfig, pcConstraints);
+    };
+    window.RTCPeerConnection.prototype = OrigPeerConnection.prototype;
+    // wrap static methods. Currently just generateCertificate.
+    Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
+      get: function() {
+        return OrigPeerConnection.generateCertificate;
+      }
+    });
+  }
+};
+
+// Expose public methods.
+module.exports = {
+  shimCallbacksAPI: safariShim.shimCallbacksAPI,
+  shimLocalStreamsAPI: safariShim.shimLocalStreamsAPI,
+  shimRemoteStreamsAPI: safariShim.shimRemoteStreamsAPI,
+  shimGetUserMedia: safariShim.shimGetUserMedia,
+  shimRTCIceServerUrls: safariShim.shimRTCIceServerUrls
+  // TODO
+  // shimPeerConnection: safariShim.shimPeerConnection
+};
+
+},{"../utils":12}],12:[function(require,module,exports){
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree.
+ */
+ /* eslint-env node */
+'use strict';
+
+var logDisabled_ = true;
+var deprecationWarnings_ = true;
+
+// Utility methods.
+var utils = {
+  disableLog: function(bool) {
+    if (typeof bool !== 'boolean') {
+      return new Error('Argument type: ' + typeof bool +
+          '. Please use a boolean.');
+    }
+    logDisabled_ = bool;
+    return (bool) ? 'adapter.js logging disabled' :
+        'adapter.js logging enabled';
+  },
+
+  /**
+   * Disable or enable deprecation warnings
+   * @param {!boolean} bool set to true to disable warnings.
+   */
+  disableWarnings: function(bool) {
+    if (typeof bool !== 'boolean') {
+      return new Error('Argument type: ' + typeof bool +
+          '. Please use a boolean.');
+    }
+    deprecationWarnings_ = !bool;
+    return 'adapter.js deprecation warnings ' + (bool ? 'disabled' : 'enabled');
+  },
+
+  log: function() {
+    if (typeof window === 'object') {
+      if (logDisabled_) {
+        return;
+      }
+      if (typeof console !== 'undefined' && typeof console.log === 'function') {
+        console.log.apply(console, arguments);
+      }
+    }
+  },
+
+  /**
+   * Shows a deprecation warning suggesting the modern and spec-compatible API.
+   */
+  deprecated: function(oldMethod, newMethod) {
+    if (!deprecationWarnings_) {
+      return;
+    }
+    console.warn(oldMethod + ' is deprecated, please use ' + newMethod +
+        ' instead.');
+  },
+
+  /**
+   * Extract browser version out of the provided user agent string.
+   *
+   * @param {!string} uastring userAgent string.
+   * @param {!string} expr Regular expression used as match criteria.
+   * @param {!number} pos position in the version string to be returned.
+   * @return {!number} browser version.
+   */
+  extractVersion: function(uastring, expr, pos) {
+    var match = uastring.match(expr);
+    return match && match.length >= pos && parseInt(match[pos], 10);
+  },
+
+  /**
+   * Browser detector.
+   *
+   * @return {object} result containing browser and version
+   *     properties.
+   */
+  detectBrowser: function(window) {
+    var navigator = window && window.navigator;
+
+    // Returned result object.
+    var result = {};
+    result.browser = null;
+    result.version = null;
+
+    // Fail early if it's not a browser
+    if (typeof window === 'undefined' || !window.navigator) {
+      result.browser = 'Not a browser.';
+      return result;
+    }
+
+    // Firefox.
+    if (navigator.mozGetUserMedia) {
+      result.browser = 'firefox';
+      result.version = this.extractVersion(navigator.userAgent,
+          /Firefox\/(\d+)\./, 1);
+    } else if (navigator.webkitGetUserMedia) {
+      // Chrome, Chromium, Webview, Opera, all use the chrome shim for now
+      if (window.webkitRTCPeerConnection) {
+        result.browser = 'chrome';
+        result.version = this.extractVersion(navigator.userAgent,
+          /Chrom(e|ium)\/(\d+)\./, 2);
+      } else { // Safari (in an unpublished version) or unknown webkit-based.
+        if (navigator.userAgent.match(/Version\/(\d+).(\d+)/)) {
+          result.browser = 'safari';
+          result.version = this.extractVersion(navigator.userAgent,
+            /AppleWebKit\/(\d+)\./, 1);
+        } else { // unknown webkit-based browser.
+          result.browser = 'Unsupported webkit-based browser ' +
+              'with GUM support but no WebRTC support.';
+          return result;
+        }
+      }
+    } else if (navigator.mediaDevices &&
+        navigator.userAgent.match(/Edge\/(\d+).(\d+)$/)) { // Edge.
+      result.browser = 'edge';
+      result.version = this.extractVersion(navigator.userAgent,
+          /Edge\/(\d+).(\d+)$/, 2);
+    } else if (navigator.mediaDevices &&
+        navigator.userAgent.match(/AppleWebKit\/(\d+)\./)) {
+        // Safari, with webkitGetUserMedia removed.
+      result.browser = 'safari';
+      result.version = this.extractVersion(navigator.userAgent,
+          /AppleWebKit\/(\d+)\./, 1);
+    } else { // Default fallthrough: not supported.
+      result.browser = 'Not a supported browser.';
+      return result;
+    }
+
+    return result;
+  },
+
+  // shimCreateObjectURL must be called before shimSourceObject to avoid loop.
+
+  shimCreateObjectURL: function(window) {
+    var URL = window && window.URL;
+
+    if (!(typeof window === 'object' && window.HTMLMediaElement &&
+          'srcObject' in window.HTMLMediaElement.prototype)) {
+      // Only shim CreateObjectURL using srcObject if srcObject exists.
+      return undefined;
+    }
+
+    var nativeCreateObjectURL = URL.createObjectURL.bind(URL);
+    var nativeRevokeObjectURL = URL.revokeObjectURL.bind(URL);
+    var streams = new Map(), newId = 0;
+
+    URL.createObjectURL = function(stream) {
+      if ('getTracks' in stream) {
+        var url = 'polyblob:' + (++newId);
+        streams.set(url, stream);
+        utils.deprecated('URL.createObjectURL(stream)',
+            'elem.srcObject = stream');
+        return url;
+      }
+      return nativeCreateObjectURL(stream);
+    };
+    URL.revokeObjectURL = function(url) {
+      nativeRevokeObjectURL(url);
+      streams.delete(url);
+    };
+
+    var dsc = Object.getOwnPropertyDescriptor(window.HTMLMediaElement.prototype,
+                                              'src');
+    Object.defineProperty(window.HTMLMediaElement.prototype, 'src', {
+      get: function() {
+        return dsc.get.apply(this);
+      },
+      set: function(url) {
+        this.srcObject = streams.get(url) || null;
+        return dsc.set.apply(this, [url]);
+      }
+    });
+
+    var nativeSetAttribute = window.HTMLMediaElement.prototype.setAttribute;
+    window.HTMLMediaElement.prototype.setAttribute = function() {
+      if (arguments.length === 2 &&
+          ('' + arguments[0]).toLowerCase() === 'src') {
+        this.srcObject = streams.get(arguments[1]) || null;
+      }
+      return nativeSetAttribute.apply(this, arguments);
+    };
+  }
+};
+
+// Export.
+module.exports = {
+  log: utils.log,
+  deprecated: utils.deprecated,
+  disableLog: utils.disableLog,
+  disableWarnings: utils.disableWarnings,
+  extractVersion: utils.extractVersion,
+  shimCreateObjectURL: utils.shimCreateObjectURL,
+  detectBrowser: utils.detectBrowser.bind(utils)
+};
+
+},{}]},{},[2])(2)
+});
\ No newline at end of file
diff --git a/admin.js b/admin.js
deleted file mode 100644 (file)
index 163bf13..0000000
--- a/admin.js
+++ /dev/null
@@ -1,25 +0,0 @@
-function makeRequest() {
-console.log('Making ajax request')
-  httpRequest = new XMLHttpRequest();
-
-  if (!httpRequest) {
-    alert('Giving up :( Cannot create an XMLHTTP instance');
-    return false;
-  }
-  httpRequest.open('GET', 'http://127.0.0.1:5140/streamlist');
-  httpRequest.onreadystatechange = function(e) {
-    if (request.readyState === 4) {
-      if (request.status === 200) {
-        console.log(request.responseText)
-      }
-    }
-  }
-  httpRequest.send()
-}
-
-
-document.addEventListener('DOMContentLoaded', function() {
-  console.log('Document is ready')
-  let streamlist = document.getElementById("streamlist")
-  document.getElementById("streams").addEventListener('click', makeRequest);
-})
similarity index 100%
rename from admin.css
rename to client/client.html
diff --git a/client/client.js b/client/client.js
new file mode 100644 (file)
index 0000000..e69de29
similarity index 100%
rename from admin.html
rename to host/host.html
diff --git a/host/host.js b/host/host.js
new file mode 100644 (file)
index 0000000..91e09c8
--- /dev/null
@@ -0,0 +1,57 @@
+function makeRequest() {
+console.log('Making ajax request')
+  httpRequest = new XMLHttpRequest();
+
+  if (!httpRequest) {
+    alert('Giving up :( Cannot create an XMLHTTP instance');
+    return false;
+  }
+  httpRequest.open('GET', 'http://127.0.0.1:5140/streamlist');
+  httpRequest.onreadystatechange = function(e) {
+    if (request.readyState === 4) {
+      if (request.status === 200) {
+        console.log(request.responseText)
+      }
+    }
+  }
+  httpRequest.send()
+}
+
+
+document.addEventListener('DOMContentLoaded', function() {
+  console.log('Document is ready')
+  let streamlist = document.getElementById("streamlist")
+  document.getElementById("streams").addEventListener('click', makeRequest);
+  // set up webrtc connection with the server
+
+  //start streaming the default streaming
+
+  //allow admin to choose
+})
+
+function getDefaultStream(event) {
+  console.log('+getDefaultStream')
+  let sendDefaultStream = (stream) => {
+    console.log(stream)
+    event.sender.send('defaultStreamResponse', stream)
+  }
+  navigator.mediaDevices.getUserMedia({
+    audio: false,
+    video: {
+      mandatory: { chromeMediaSource: 'desktop' }
+    }
+  }).then(sendDefaultStream,(err) => {
+    desktopCapturer.getSources({types: ['window', 'screen']}, (error, sources) => {
+      if (error) {
+       console.log(error)
+       return
+      }
+      navigator.mediaDevices.getUserMedia({
+       audio: false,
+       video: {
+         mandatory: { chromeMediaSourceId: sources[0].id }
+       }
+      }).then(sendDefaultStream,(err) => { console.log(err) })
+    })
+  })
+}
diff --git a/main.js b/main.js
index ff85c9c..4ae47da 100644 (file)
--- a/main.js
+++ b/main.js
@@ -1,71 +1,58 @@
 const electron = require('electron')
-const http = require('http')
-const path = require('path')
+const app = electron.app
 const url = require('url')
+const WebSocket = require('ws')
+const http = require('http')
 const fs = require('fs')
-const app = electron.app
-const BrowserWindow = electron.BrowserWindow
-const ipcMain = electron.ipcMain
-
-let mainWindow
-
-function beginRendererProcess() {
-  mainWindow = new BrowserWindow({show: true, webPreferences: { webSecurity: false, experimentalFeatures: true}})
-  mainWindow.loadURL(url.format({
-    pathname: path.join(__dirname, 'renderer.html'),
-    protocol: 'file:',
-    slashes: true
-  }))
-  mainWindow.webContents.openDevTools()
-}
-
-function captureStream() {
-  mainWindow.webContents.send('defaultStreamRequest', 'slr')
-  let p = new Promise((resolve,reject) => {
-    ipcMain.on('defaultStreamResponse', (event, arg) => {
-      console.log('received defaultStreamResponse')
-      console.log(arg)
-      resolve(arg)
-    })
-  })
-
-  return p
-}
-
 
 const routes = {
   '/': function root(response) {
-    response.write(fs.readFileSync('admin.html'))
+    response.write(fs.readFileSync('host/host.html'))
     response.end()
   },
   '/admin.js': function js(response) {
-    response.write(fs.readFileSync('admin.js'))
+    response.write(fs.readFileSync('host/host.js'))
     response.end()
   },
-  '/admin.css': function css(response) {
-    response.write(fs.readFileSync('admin.css'))
+  '/adapter.js': function adapter(response) {
+    response.write(fs.readFileSync('adapter.js'))
     response.end()
   },
-  '/favicon.ico': function favicon() {
+  '/favicon.ico': function favicon(response) {
+    response.write('N/A')
     response.end()
   },
   '/streamlist': function streamlist(response) {
-    let mediaStream = captureStream().then((stream) => {
-      console.log(stream)
-    })
-
-    //response.write(mediaStream)
+    getDefaultStream()
   }
 }
 
-app.on('ready', function() {
-  beginRendererProcess()
+const rooms = {}
+
 
+/* TODO: Swap out url.parse with regex? */
+function determineResponse(request) {
+  const clientIP  = request.connection.remoteAddress
+                  || request.socket.remoteAddress
+                  || request.connection.socket.remoteAddress
+                  || req.headers['x-forwarded-for'].split(',')[0]
+  const parsedURL = url.parse(request.url)
 
+  /* Get the room name */
+  const pathname = parsedURL.pathname
+
+
+}
+
+app.on('ready', function() {
+  console.log('create server')
   http.createServer(function(request, response) {
-    const url = request.url
-    console.log('routing to ' + url);
-    routes[url](response)
+
+    let route = determineResponse(request)
+
+    console.log('routing to ' + route)
+    routes[route](response)
 
   }).listen(5140);
+
 });
index 6d7e957..ed07cd4 100644 (file)
   "keywords": [
     "WebRTC",
     "Cool",
-    "Screen Sharing",
+    "Desktop Sharing",
     "Distributed",
     "Prototype"
   ],
-  "author": "Jordan Lavatai",
+  "author": [ "Jordan Lavatai", "Ken Grimes" ],
   "license": "MIT",
   "devDependencies": {},
   "dependencies": {
-    "electron": "^1.6.11"
+    "electron": "^1.6.11",
+    "ws": "^3.0.0"
   }
 }
diff --git a/renderer.html b/renderer.html
deleted file mode 100644 (file)
index ee9a802..0000000
+++ /dev/null
@@ -1,9 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <meta charset="utf-8">
-  </head>
-  <body>
-  </body>
-  <script src="renderer.js"></script>
-</html>
diff --git a/renderer.js b/renderer.js
deleted file mode 100644 (file)
index d98bb50..0000000
+++ /dev/null
@@ -1,38 +0,0 @@
-const ipcRenderer = require('electron').ipcRenderer
-const {desktopCapturer} = require('electron')
-
-let mediaStream
-
-
-function getDefaultStream(event) {
-  console.log('+getDefaultStream')
-  let sendDefaultStream = (stream) => {
-    mediaStream = stream
-    console.log(stream)
-    event.sender.send('defaultStreamResponse', stream)
-  }
-  navigator.mediaDevices.getUserMedia({
-    audio: false,
-    video: {
-      mandatory: { chromeMediaSource: 'desktop' }
-    }
-  }).then(sendDefaultStream,(err) => {
-    desktopCapturer.getSources({types: ['window', 'screen']}, (error, sources) => {
-      if (error) {
-       console.log(error)
-       return
-      }
-      navigator.mediaDevices.getUserMedia({
-       audio: false,
-       video: {
-         mandatory: { chromeMediaSourceId: sources[0].id }
-       }
-      }).then(sendDefaultStream,(err) => { console.log(err) })
-    })
-  })
-}
-
-ipcRenderer.on('defaultStreamRequest', (event, message) => {
-  console.log('defaultStreamRequest received, grabbing media stream for screen1')
-  getDefaultStream(event)
-})