liang-z-screenshot/dist/screenShotPlugin.common.js

vue-web-screen-shot 修复 html2canvas 截图 图片空白

module.exports =
/******/ (function(modules) { // webpackBootstrap
/******/ 	// The module cache
/******/ 	var installedModules = {};
/******/
/******/ 	// The require function
/******/ 	function __webpack_require__(moduleId) {
/******/
/******/ 		// Check if module is in cache
/******/ 		if(installedModules[moduleId]) {
/******/ 			return installedModules[moduleId].exports;
/******/ 		}
/******/ 		// Create a new module (and put it into the cache)
/******/ 		var module = installedModules[moduleId] = {
/******/ 			i: moduleId,
/******/ 			l: false,
/******/ 			exports: {}
/******/ 		};
/******/
/******/ 		// Execute the module function
/******/ 		modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
/******/
/******/ 		// Flag the module as loaded
/******/ 		module.l = true;
/******/
/******/ 		// Return the exports of the module
/******/ 		return module.exports;
/******/ 	}
/******/
/******/
/******/ 	// expose the modules object (__webpack_modules__)
/******/ 	__webpack_require__.m = modules;
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/******/ 	// expose the module cache
/******/ 	__webpack_require__.c = installedModules;
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/******/ 	__webpack_require__.d = function(exports, name, getter) {
/******/ 		if(!__webpack_require__.o(exports, name)) {
/******/ 			Object.defineProperty(exports, name, { enumerable: true, get: getter });
/******/ 		}
/******/ 	};
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/******/ 	// define __esModule on exports
/******/ 	__webpack_require__.r = function(exports) {
/******/ 		if(typeof Symbol !== 'undefined' && Symbol.toStringTag) {
/******/ 			Object.defineProperty(exports, Symbol.toStringTag, { value: 'Module' });
/******/ 		}
/******/ 		Object.defineProperty(exports, '__esModule', { value: true });
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/******/ 	// mode & 1: value is a module id, require it
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/******/ 	// mode & 4: return value when already ns object
/******/ 	// mode & 8|1: behave like require
/******/ 	__webpack_require__.t = function(value, mode) {
/******/ 		if(mode & 1) value = __webpack_require__(value);
/******/ 		if(mode & 8) return value;
/******/ 		if((mode & 4) && typeof value === 'object' && value && value.__esModule) return value;
/******/ 		var ns = Object.create(null);
/******/ 		__webpack_require__.r(ns);
/******/ 		Object.defineProperty(ns, 'default', { enumerable: true, value: value });
/******/ 		if(mode & 2 && typeof value != 'string') for(var key in value) __webpack_require__.d(ns, key, function(key) { return value[key]; }.bind(null, key));
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/******/ 	__webpack_require__.n = function(module) {
/******/ 		var getter = module && module.__esModule ?
/******/ 			function getDefault() { return module['default']; } :
/******/ 			function getModuleExports() { return module; };
/******/ 		__webpack_require__.d(getter, 'a', getter);
/******/ 		return getter;
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/******/ 	__webpack_require__.o = function(object, property) { return Object.prototype.hasOwnProperty.call(object, property); };
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/******/ 	return __webpack_require__(__webpack_require__.s = "fb15");
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/******/ ({

/***/ "00ee":
/***/ (function(module, exports, __webpack_require__) {

var wellKnownSymbol = __webpack_require__("b622");

var TO_STRING_TAG = wellKnownSymbol('toStringTag');
var test = {};

test[TO_STRING_TAG] = 'z';

module.exports = String(test) === '[object z]';


/***/ }),

/***/ "0366":
/***/ (function(module, exports, __webpack_require__) {

var aFunction = __webpack_require__("1c0b");

// optional / simple context binding
module.exports = function (fn, that, length) {
  aFunction(fn);
  if (that === undefined) return fn;
  switch (length) {
    case 0: return function () {
      return fn.call(that);
    };
    case 1: return function (a) {
      return fn.call(that, a);
    };
    case 2: return function (a, b) {
      return fn.call(that, a, b);
    };
    case 3: return function (a, b, c) {
      return fn.call(that, a, b, c);
    };
  }
  return function (/* ...args */) {
    return fn.apply(that, arguments);
  };
};


/***/ }),

/***/ "04b3":
/***/ (function(module, exports) {

module.exports = "data:image/png;base64,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"

/***/ }),

/***/ "06cf":
/***/ (function(module, exports, __webpack_require__) {

var DESCRIPTORS = __webpack_require__("83ab");
var propertyIsEnumerableModule = __webpack_require__("d1e7");
var createPropertyDescriptor = __webpack_require__("5c6c");
var toIndexedObject = __webpack_require__("fc6a");
var toPrimitive = __webpack_require__("c04e");
var has = __webpack_require__("5135");
var IE8_DOM_DEFINE = __webpack_require__("0cfb");

var nativeGetOwnPropertyDescriptor = Object.getOwnPropertyDescriptor;

// `Object.getOwnPropertyDescriptor` method
// https://tc39.es/ecma262/#sec-object.getownpropertydescriptor
exports.f = DESCRIPTORS ? nativeGetOwnPropertyDescriptor : function getOwnPropertyDescriptor(O, P) {
  O = toIndexedObject(O);
  P = toPrimitive(P, true);
  if (IE8_DOM_DEFINE) try {
    return nativeGetOwnPropertyDescriptor(O, P);
  } catch (error) { /* empty */ }
  if (has(O, P)) return createPropertyDescriptor(!propertyIsEnumerableModule.f.call(O, P), O[P]);
};


/***/ }),

/***/ "0cfb":
/***/ (function(module, exports, __webpack_require__) {

var DESCRIPTORS = __webpack_require__("83ab");
var fails = __webpack_require__("d039");
var createElement = __webpack_require__("cc12");

// Thank's IE8 for his funny defineProperty
module.exports = !DESCRIPTORS && !fails(function () {
  return Object.defineProperty(createElement('div'), 'a', {
    get: function () { return 7; }
  }).a != 7;
});


/***/ }),

/***/ "159b":
/***/ (function(module, exports, __webpack_require__) {

var global = __webpack_require__("da84");
var DOMIterables = __webpack_require__("fdbc");
var forEach = __webpack_require__("17c2");
var createNonEnumerableProperty = __webpack_require__("9112");

for (var COLLECTION_NAME in DOMIterables) {
  var Collection = global[COLLECTION_NAME];
  var CollectionPrototype = Collection && Collection.prototype;
  // some Chrome versions have non-configurable methods on DOMTokenList
  if (CollectionPrototype && CollectionPrototype.forEach !== forEach) try {
    createNonEnumerableProperty(CollectionPrototype, 'forEach', forEach);
  } catch (error) {
    CollectionPrototype.forEach = forEach;
  }
}


/***/ }),

/***/ "17c2":
/***/ (function(module, exports, __webpack_require__) {

"use strict";

var $forEach = __webpack_require__("b727").forEach;
var arrayMethodIsStrict = __webpack_require__("a640");
var arrayMethodUsesToLength = __webpack_require__("ae40");

var STRICT_METHOD = arrayMethodIsStrict('forEach');
var USES_TO_LENGTH = arrayMethodUsesToLength('forEach');

// `Array.prototype.forEach` method implementation
// https://tc39.es/ecma262/#sec-array.prototype.foreach
module.exports = (!STRICT_METHOD || !USES_TO_LENGTH) ? function forEach(callbackfn /* , thisArg */) {
  return $forEach(this, callbackfn, arguments.length > 1 ? arguments[1] : undefined);
} : [].forEach;


/***/ }),

/***/ "19aa":
/***/ (function(module, exports) {

module.exports = function (it, Constructor, name) {
  if (!(it instanceof Constructor)) {
    throw TypeError('Incorrect ' + (name ? name + ' ' : '') + 'invocation');
  } return it;
};


/***/ }),

/***/ "1be4":
/***/ (function(module, exports, __webpack_require__) {

var getBuiltIn = __webpack_require__("d066");

module.exports = getBuiltIn('document', 'documentElement');


/***/ }),

/***/ "1bef":
/***/ (function(module, exports) {

module.exports = "data:image/png;base64,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"

/***/ }),

/***/ "1c0b":
/***/ (function(module, exports) {

module.exports = function (it) {
  if (typeof it != 'function') {
    throw TypeError(String(it) + ' is not a function');
  } return it;
};


/***/ }),

/***/ "1c7e":
/***/ (function(module, exports, __webpack_require__) {

var wellKnownSymbol = __webpack_require__("b622");

var ITERATOR = wellKnownSymbol('iterator');
var SAFE_CLOSING = false;

try {
  var called = 0;
  var iteratorWithReturn = {
    next: function () {
      return { done: !!called++ };
    },
    'return': function () {
      SAFE_CLOSING = true;
    }
  };
  iteratorWithReturn[ITERATOR] = function () {
    return this;
  };
  // eslint-disable-next-line no-throw-literal
  Array.from(iteratorWithReturn, function () { throw 2; });
} catch (error) { /* empty */ }

module.exports = function (exec, SKIP_CLOSING) {
  if (!SKIP_CLOSING && !SAFE_CLOSING) return false;
  var ITERATION_SUPPORT = false;
  try {
    var object = {};
    object[ITERATOR] = function () {
      return {
        next: function () {
          return { done: ITERATION_SUPPORT = true };
        }
      };
    };
    exec(object);
  } catch (error) { /* empty */ }
  return ITERATION_SUPPORT;
};


/***/ }),

/***/ "1cdc":
/***/ (function(module, exports, __webpack_require__) {

var userAgent = __webpack_require__("342f");

module.exports = /(iphone|ipod|ipad).*applewebkit/i.test(userAgent);


/***/ }),

/***/ "1d80":
/***/ (function(module, exports) {

// `RequireObjectCoercible` abstract operation
// https://tc39.es/ecma262/#sec-requireobjectcoercible
module.exports = function (it) {
  if (it == undefined) throw TypeError("Can't call method on " + it);
  return it;
};


/***/ }),

/***/ "1de5":
/***/ (function(module, exports, __webpack_require__) {

"use strict";


module.exports = function (url, options) {
  if (!options) {
    // eslint-disable-next-line no-param-reassign
    options = {};
  } // eslint-disable-next-line no-underscore-dangle, no-param-reassign


  url = url && url.__esModule ? url.default : url;

  if (typeof url !== 'string') {
    return url;
  } // If url is already wrapped in quotes, remove them


  if (/^['"].*['"]$/.test(url)) {
    // eslint-disable-next-line no-param-reassign
    url = url.slice(1, -1);
  }

  if (options.hash) {
    // eslint-disable-next-line no-param-reassign
    url += options.hash;
  } // Should url be wrapped?
  // See https://drafts.csswg.org/css-values-3/#urls


  if (/["'() \t\n]/.test(url) || options.needQuotes) {
    return "\"".concat(url.replace(/"/g, '\\"').replace(/\n/g, '\\n'), "\"");
  }

  return url;
};

/***/ }),

/***/ "2266":
/***/ (function(module, exports, __webpack_require__) {

var anObject = __webpack_require__("825a");
var isArrayIteratorMethod = __webpack_require__("e95a");
var toLength = __webpack_require__("50c4");
var bind = __webpack_require__("0366");
var getIteratorMethod = __webpack_require__("35a1");
var iteratorClose = __webpack_require__("2a62");

var Result = function (stopped, result) {
  this.stopped = stopped;
  this.result = result;
};

module.exports = function (iterable, unboundFunction, options) {
  var that = options && options.that;
  var AS_ENTRIES = !!(options && options.AS_ENTRIES);
  var IS_ITERATOR = !!(options && options.IS_ITERATOR);
  var INTERRUPTED = !!(options && options.INTERRUPTED);
  var fn = bind(unboundFunction, that, 1 + AS_ENTRIES + INTERRUPTED);
  var iterator, iterFn, index, length, result, next, step;

  var stop = function (condition) {
    if (iterator) iteratorClose(iterator);
    return new Result(true, condition);
  };

  var callFn = function (value) {
    if (AS_ENTRIES) {
      anObject(value);
      return INTERRUPTED ? fn(value[0], value[1], stop) : fn(value[0], value[1]);
    } return INTERRUPTED ? fn(value, stop) : fn(value);
  };

  if (IS_ITERATOR) {
    iterator = iterable;
  } else {
    iterFn = getIteratorMethod(iterable);
    if (typeof iterFn != 'function') throw TypeError('Target is not iterable');
    // optimisation for array iterators
    if (isArrayIteratorMethod(iterFn)) {
      for (index = 0, length = toLength(iterable.length); length > index; index++) {
        result = callFn(iterable[index]);
        if (result && result instanceof Result) return result;
      } return new Result(false);
    }
    iterator = iterFn.call(iterable);
  }

  next = iterator.next;
  while (!(step = next.call(iterator)).done) {
    try {
      result = callFn(step.value);
    } catch (error) {
      iteratorClose(iterator);
      throw error;
    }
    if (typeof result == 'object' && result && result instanceof Result) return result;
  } return new Result(false);
};


/***/ }),

/***/ "23cb":
/***/ (function(module, exports, __webpack_require__) {

var toInteger = __webpack_require__("a691");

var max = Math.max;
var min = Math.min;

// Helper for a popular repeating case of the spec:
// Let integer be ? ToInteger(index).
// If integer < 0, let result be max((length + integer), 0); else let result be min(integer, length).
module.exports = function (index, length) {
  var integer = toInteger(index);
  return integer < 0 ? max(integer + length, 0) : min(integer, length);
};


/***/ }),

/***/ "23e7":
/***/ (function(module, exports, __webpack_require__) {

var global = __webpack_require__("da84");
var getOwnPropertyDescriptor = __webpack_require__("06cf").f;
var createNonEnumerableProperty = __webpack_require__("9112");
var redefine = __webpack_require__("6eeb");
var setGlobal = __webpack_require__("ce4e");
var copyConstructorProperties = __webpack_require__("e893");
var isForced = __webpack_require__("94ca");

/*
  options.target      - name of the target object
  options.global      - target is the global object
  options.stat        - export as static methods of target
  options.proto       - export as prototype methods of target
  options.real        - real prototype method for the `pure` version
  options.forced      - export even if the native feature is available
  options.bind        - bind methods to the target, required for the `pure` version
  options.wrap        - wrap constructors to preventing global pollution, required for the `pure` version
  options.unsafe      - use the simple assignment of property instead of delete + defineProperty
  options.sham        - add a flag to not completely full polyfills
  options.enumerable  - export as enumerable property
  options.noTargetGet - prevent calling a getter on target
*/
module.exports = function (options, source) {
  var TARGET = options.target;
  var GLOBAL = options.global;
  var STATIC = options.stat;
  var FORCED, target, key, targetProperty, sourceProperty, descriptor;
  if (GLOBAL) {
    target = global;
  } else if (STATIC) {
    target = global[TARGET] || setGlobal(TARGET, {});
  } else {
    target = (global[TARGET] || {}).prototype;
  }
  if (target) for (key in source) {
    sourceProperty = source[key];
    if (options.noTargetGet) {
      descriptor = getOwnPropertyDescriptor(target, key);
      targetProperty = descriptor && descriptor.value;
    } else targetProperty = target[key];
    FORCED = isForced(GLOBAL ? key : TARGET + (STATIC ? '.' : '#') + key, options.forced);
    // contained in target
    if (!FORCED && targetProperty !== undefined) {
      if (typeof sourceProperty === typeof targetProperty) continue;
      copyConstructorProperties(sourceProperty, targetProperty);
    }
    // add a flag to not completely full polyfills
    if (options.sham || (targetProperty && targetProperty.sham)) {
      createNonEnumerableProperty(sourceProperty, 'sham', true);
    }
    // extend global
    redefine(target, key, sourceProperty, options);
  }
};


/***/ }),

/***/ "241c":
/***/ (function(module, exports, __webpack_require__) {

var internalObjectKeys = __webpack_require__("ca84");
var enumBugKeys = __webpack_require__("7839");

var hiddenKeys = enumBugKeys.concat('length', 'prototype');

// `Object.getOwnPropertyNames` method
// https://tc39.es/ecma262/#sec-object.getownpropertynames
exports.f = Object.getOwnPropertyNames || function getOwnPropertyNames(O) {
  return internalObjectKeys(O, hiddenKeys);
};


/***/ }),

/***/ "24fb":
/***/ (function(module, exports, __webpack_require__) {

"use strict";


/*
  MIT License http://www.opensource.org/licenses/mit-license.php
  Author Tobias Koppers @sokra
*/
// css base code, injected by the css-loader
// eslint-disable-next-line func-names
module.exports = function (useSourceMap) {
  var list = []; // return the list of modules as css string

  list.toString = function toString() {
    return this.map(function (item) {
      var content = cssWithMappingToString(item, useSourceMap);

      if (item[2]) {
        return "@media ".concat(item[2], " {").concat(content, "}");
      }

      return content;
    }).join('');
  }; // import a list of modules into the list
  // eslint-disable-next-line func-names


  list.i = function (modules, mediaQuery, dedupe) {
    if (typeof modules === 'string') {
      // eslint-disable-next-line no-param-reassign
      modules = [[null, modules, '']];
    }

    var alreadyImportedModules = {};

    if (dedupe) {
      for (var i = 0; i < this.length; i++) {
        // eslint-disable-next-line prefer-destructuring
        var id = this[i][0];

        if (id != null) {
          alreadyImportedModules[id] = true;
        }
      }
    }

    for (var _i = 0; _i < modules.length; _i++) {
      var item = [].concat(modules[_i]);

      if (dedupe && alreadyImportedModules[item[0]]) {
        // eslint-disable-next-line no-continue
        continue;
      }

      if (mediaQuery) {
        if (!item[2]) {
          item[2] = mediaQuery;
        } else {
          item[2] = "".concat(mediaQuery, " and ").concat(item[2]);
        }
      }

      list.push(item);
    }
  };

  return list;
};

function cssWithMappingToString(item, useSourceMap) {
  var content = item[1] || ''; // eslint-disable-next-line prefer-destructuring

  var cssMapping = item[3];

  if (!cssMapping) {
    return content;
  }

  if (useSourceMap && typeof btoa === 'function') {
    var sourceMapping = toComment(cssMapping);
    var sourceURLs = cssMapping.sources.map(function (source) {
      return "/*# sourceURL=".concat(cssMapping.sourceRoot || '').concat(source, " */");
    });
    return [content].concat(sourceURLs).concat([sourceMapping]).join('\n');
  }

  return [content].join('\n');
} // Adapted from convert-source-map (MIT)


function toComment(sourceMap) {
  // eslint-disable-next-line no-undef
  var base64 = btoa(unescape(encodeURIComponent(JSON.stringify(sourceMap))));
  var data = "sourceMappingURL=data:application/json;charset=utf-8;base64,".concat(base64);
  return "/*# ".concat(data, " */");
}

/***/ }),

/***/ "2532":
/***/ (function(module, exports, __webpack_require__) {

"use strict";

var $ = __webpack_require__("23e7");
var notARegExp = __webpack_require__("5a34");
var requireObjectCoercible = __webpack_require__("1d80");
var correctIsRegExpLogic = __webpack_require__("ab13");

// `String.prototype.includes` method
// https://tc39.es/ecma262/#sec-string.prototype.includes
$({ target: 'String', proto: true, forced: !correctIsRegExpLogic('includes') }, {
  includes: function includes(searchString /* , position = 0 */) {
    return !!~String(requireObjectCoercible(this))
      .indexOf(notARegExp(searchString), arguments.length > 1 ? arguments[1] : undefined);
  }
});


/***/ }),

/***/ "2626":
/***/ (function(module, exports, __webpack_require__) {

"use strict";

var getBuiltIn = __webpack_require__("d066");
var definePropertyModule = __webpack_require__("9bf2");
var wellKnownSymbol = __webpack_require__("b622");
var DESCRIPTORS = __webpack_require__("83ab");

var SPECIES = wellKnownSymbol('species');

module.exports = function (CONSTRUCTOR_NAME) {
  var Constructor = getBuiltIn(CONSTRUCTOR_NAME);
  var defineProperty = definePropertyModule.f;

  if (DESCRIPTORS && Constructor && !Constructor[SPECIES]) {
    defineProperty(Constructor, SPECIES, {
      configurable: true,
      get: function () { return this; }
    });
  }
};


/***/ }),

/***/ "282b":
/***/ (function(module, exports, __webpack_require__) {

"use strict";
/* eslint-env node */


// 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 the session description.
SDPUtils.getDescription = function(blob) {
  var sections = SDPUtils.splitSections(blob);
  return sections && sections[0];
};

// returns the individual media sections.
SDPUtils.getMediaSections = function(blob) {
  var sections = SDPUtils.splitSections(blob);
  sections.shift();
  return sections;
};

// 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],
    address: parts[4], // address is an alias for ip.
    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;
      case 'ufrag':
        candidate.ufrag = parts[i + 1]; // for backward compability.
        candidate.usernameFragment = 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.address || 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);
    sdp.push('rport');
    sdp.push(candidate.relatedPort);
  }
  if (candidate.tcpType && candidate.protocol.toLowerCase() === 'tcp') {
    sdp.push('tcptype');
    sdp.push(candidate.tcpType);
  }
  if (candidate.usernameFragment || candidate.ufrag) {
    sdp.push('ufrag');
    sdp.push(candidate.usernameFragment || 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
  parsed.channels = parts.length === 3 ? parseInt(parts[2], 10) : 1;
  // legacy alias, got renamed back to channels in ORTC.
  parsed.numChannels = parsed.channels;
  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;
  }
  var channels = codec.channels || codec.numChannels || 1;
  return 'a=rtpmap:' + pt + ' ' + codec.name + '/' + codec.clockRate +
      (channels !== 1 ? '/' + channels : '') + '\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) {
      if (codec.parameters[param]) {
        params.push(param + '=' + codec.parameters[param]);
      } else {
        params.push(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;
};

SDPUtils.parseSsrcGroup = function(line) {
  var parts = line.substr(13).split(' ');
  return {
    semantics: parts.shift(),
    ssrcs: parts.map(function(ssrc) {
      return parseInt(ssrc, 10);
    })
  };
};

// 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 a=crypto lines into
//   https://rawgit.com/aboba/edgertc/master/msortc-rs4.html#dictionary-rtcsrtpsdesparameters-members
SDPUtils.parseCryptoLine = function(line) {
  var parts = line.substr(9).split(' ');
  return {
    tag: parseInt(parts[0], 10),
    cryptoSuite: parts[1],
    keyParams: parts[2],
    sessionParams: parts.slice(3),
  };
};

SDPUtils.writeCryptoLine = function(parameters) {
  return 'a=crypto:' + parameters.tag + ' ' +
    parameters.cryptoSuite + ' ' +
    (typeof parameters.keyParams === 'object'
      ? SDPUtils.writeCryptoKeyParams(parameters.keyParams)
      : parameters.keyParams) +
    (parameters.sessionParams ? ' ' + parameters.sessionParams.join(' ') : '') +
    '\r\n';
};

// Parses the crypto key parameters into
//   https://rawgit.com/aboba/edgertc/master/msortc-rs4.html#rtcsrtpkeyparam*
SDPUtils.parseCryptoKeyParams = function(keyParams) {
  if (keyParams.indexOf('inline:') !== 0) {
    return null;
  }
  var parts = keyParams.substr(7).split('|');
  return {
    keyMethod: 'inline',
    keySalt: parts[0],
    lifeTime: parts[1],
    mkiValue: parts[2] ? parts[2].split(':')[0] : undefined,
    mkiLength: parts[2] ? parts[2].split(':')[1] : undefined,
  };
};

SDPUtils.writeCryptoKeyParams = function(keyParams) {
  return keyParams.keyMethod + ':'
    + keyParams.keySalt +
    (keyParams.lifeTime ? '|' + keyParams.lifeTime : '') +
    (keyParams.mkiValue && keyParams.mkiLength
      ? '|' + keyParams.mkiValue + ':' + keyParams.mkiLength
      : '');
};

// Extracts all SDES paramters.
SDPUtils.getCryptoParameters = function(mediaSection, sessionpart) {
  var lines = SDPUtils.matchPrefix(mediaSection + sessionpart,
    'a=crypto:');
  return lines.map(SDPUtils.parseCryptoLine);
};

// 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 ufrag = SDPUtils.matchPrefix(mediaSection + sessionpart,
    'a=ice-ufrag:')[0];
  var pwd = SDPUtils.matchPrefix(mediaSection + sessionpart,
    'a=ice-pwd:')[0];
  if (!(ufrag && pwd)) {
    return null;
  }
  return {
    usernameFragment: ufrag.substr(12),
    password: pwd.substr(10),
  };
};

// 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';

  if (caps.headerExtensions) {
    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.substr(17).split(' ');
      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)
      };
      if (primarySsrc && secondarySsrc) {
        encParam.rtx = {ssrc: secondarySsrc};
      }
      encodingParameters.push(encParam);
      if (hasRed) {
        encParam = JSON.parse(JSON.stringify(encParam));
        encParam.fec = {
          ssrc: primarySsrc,
          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 = {};

  // Gets the first SSRC. Note tha 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 attrіbute.
  // 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(msidParts) {
      return msidParts.attribute === 'msid';
    });
  if (planB.length > 0) {
    parts = planB[0].value.split(' ');
    return {stream: parts[0], track: parts[1]};
  }
};

// SCTP
// parses draft-ietf-mmusic-sctp-sdp-26 first and falls back
// to draft-ietf-mmusic-sctp-sdp-05
SDPUtils.parseSctpDescription = function(mediaSection) {
  var mline = SDPUtils.parseMLine(mediaSection);
  var maxSizeLine = SDPUtils.matchPrefix(mediaSection, 'a=max-message-size:');
  var maxMessageSize;
  if (maxSizeLine.length > 0) {
    maxMessageSize = parseInt(maxSizeLine[0].substr(19), 10);
  }
  if (isNaN(maxMessageSize)) {
    maxMessageSize = 65536;
  }
  var sctpPort = SDPUtils.matchPrefix(mediaSection, 'a=sctp-port:');
  if (sctpPort.length > 0) {
    return {
      port: parseInt(sctpPort[0].substr(12), 10),
      protocol: mline.fmt,
      maxMessageSize: maxMessageSize
    };
  }
  var sctpMapLines = SDPUtils.matchPrefix(mediaSection, 'a=sctpmap:');
  if (sctpMapLines.length > 0) {
    var parts = SDPUtils.matchPrefix(mediaSection, 'a=sctpmap:')[0]
      .substr(10)
      .split(' ');
    return {
      port: parseInt(parts[0], 10),
      protocol: parts[1],
      maxMessageSize: maxMessageSize
    };
  }
};

// SCTP
// outputs the draft-ietf-mmusic-sctp-sdp-26 version that all browsers
// support by now receiving in this format, unless we originally parsed
// as the draft-ietf-mmusic-sctp-sdp-05 format (indicated by the m-line
// protocol of DTLS/SCTP -- without UDP/ or TCP/)
SDPUtils.writeSctpDescription = function(media, sctp) {
  var output = [];
  if (media.protocol !== 'DTLS/SCTP') {
    output = [
      'm=' + media.kind + ' 9 ' + media.protocol + ' ' + sctp.protocol + '\r\n',
      'c=IN IP4 0.0.0.0\r\n',
      'a=sctp-port:' + sctp.port + '\r\n'
    ];
  } else {
    output = [
      'm=' + media.kind + ' 9 ' + media.protocol + ' ' + sctp.port + '\r\n',
      'c=IN IP4 0.0.0.0\r\n',
      'a=sctpmap:' + sctp.port + ' ' + sctp.protocol + ' 65535\r\n'
    ];
  }
  if (sctp.maxMessageSize !== undefined) {
    output.push('a=max-message-size:' + sctp.maxMessageSize + '\r\n');
  }
  return output.join('');
};

// 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
// sessVersion is optional and defaults to 2
// sessUser is optional and defaults to 'thisisadapterortc'
SDPUtils.writeSessionBoilerplate = function(sessId, sessVer, sessUser) {
  var sessionId;
  var version = sessVer !== undefined ? sessVer : 2;
  if (sessId) {
    sessionId = sessId;
  } else {
    sessionId = SDPUtils.generateSessionId();
  }
  var user = sessUser || 'thisisadapterortc';
  // FIXME: sess-id should be an NTP timestamp.
  return 'v=0\r\n' +
      'o=' + user + ' ' + sessionId + ' ' + version +
        ' 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';
};

SDPUtils.parseMLine = function(mediaSection) {
  var lines = SDPUtils.splitLines(mediaSection);
  var parts = lines[0].substr(2).split(' ');
  return {
    kind: parts[0],
    port: parseInt(parts[1], 10),
    protocol: parts[2],
    fmt: parts.slice(3).join(' ')
  };
};

SDPUtils.parseOLine = function(mediaSection) {
  var line = SDPUtils.matchPrefix(mediaSection, 'o=')[0];
  var parts = line.substr(2).split(' ');
  return {
    username: parts[0],
    sessionId: parts[1],
    sessionVersion: parseInt(parts[2], 10),
    netType: parts[3],
    addressType: parts[4],
    address: parts[5]
  };
};

// a very naive interpretation of a valid SDP.
SDPUtils.isValidSDP = function(blob) {
  if (typeof blob !== 'string' || blob.length === 0) {
    return false;
  }
  var lines = SDPUtils.splitLines(blob);
  for (var i = 0; i < lines.length; i++) {
    if (lines[i].length < 2 || lines[i].charAt(1) !== '=') {
      return false;
    }
    // TODO: check the modifier a bit more.
  }
  return true;
};

// Expose public methods.
if (true) {
  module.exports = SDPUtils;
}


/***/ }),

/***/ "2a62":
/***/ (function(module, exports, __webpack_require__) {

var anObject = __webpack_require__("825a");

module.exports = function (iterator) {
  var returnMethod = iterator['return'];
  if (returnMethod !== undefined) {
    return anObject(returnMethod.call(iterator)).value;
  }
};


/***/ }),

/***/ "2c1e":
/***/ (function(module, exports) {

module.exports = "data:image/png;base64,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"

/***/ }),

/***/ "2cf4":
/***/ (function(module, exports, __webpack_require__) {

var global = __webpack_require__("da84");
var fails = __webpack_require__("d039");
var bind = __webpack_require__("0366");
var html = __webpack_require__("1be4");
var createElement = __webpack_require__("cc12");
var IS_IOS = __webpack_require__("1cdc");
var IS_NODE = __webpack_require__("605d");

var location = global.location;
var set = global.setImmediate;
var clear = global.clearImmediate;
var process = global.process;
var MessageChannel = global.MessageChannel;
var Dispatch = global.Dispatch;
var counter = 0;
var queue = {};
var ONREADYSTATECHANGE = 'onreadystatechange';
var defer, channel, port;

var run = function (id) {
  // eslint-disable-next-line no-prototype-builtins
  if (queue.hasOwnProperty(id)) {
    var fn = queue[id];
    delete queue[id];
    fn();
  }
};

var runner = function (id) {
  return function () {
    run(id);
  };
};

var listener = function (event) {
  run(event.data);
};

var post = function (id) {
  // old engines have not location.origin
  global.postMessage(id + '', location.protocol + '//' + location.host);
};

// Node.js 0.9+ & IE10+ has setImmediate, otherwise:
if (!set || !clear) {
  set = function setImmediate(fn) {
    var args = [];
    var i = 1;
    while (arguments.length > i) args.push(arguments[i++]);
    queue[++counter] = function () {
      // eslint-disable-next-line no-new-func
      (typeof fn == 'function' ? fn : Function(fn)).apply(undefined, args);
    };
    defer(counter);
    return counter;
  };
  clear = function clearImmediate(id