bundle.js

(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){
'use strict'

exports.byteLength = byteLength
exports.toByteArray = toByteArray
exports.fromByteArray = fromByteArray

var lookup = []
var revLookup = []
var Arr = typeof Uint8Array !== 'undefined' ? Uint8Array : Array

var code = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
for (var i = 0, len = code.length; i < len; ++i) {
  lookup[i] = code[i]
  revLookup[code.charCodeAt(i)] = i
}

revLookup['-'.charCodeAt(0)] = 62
revLookup['_'.charCodeAt(0)] = 63

function placeHoldersCount (b64) {
  var len = b64.length
  if (len % 4 > 0) {
    throw new Error('Invalid string. Length must be a multiple of 4')
  }

  // the number of equal signs (place holders)
  // if there are two placeholders, than the two characters before it
  // represent one byte
  // if there is only one, then the three characters before it represent 2 bytes
  // this is just a cheap hack to not do indexOf twice
  return b64[len - 2] === '=' ? 2 : b64[len - 1] === '=' ? 1 : 0
}

function byteLength (b64) {
  // base64 is 4/3 + up to two characters of the original data
  return b64.length * 3 / 4 - placeHoldersCount(b64)
}

function toByteArray (b64) {
  var i, j, l, tmp, placeHolders, arr
  var len = b64.length
  placeHolders = placeHoldersCount(b64)

  arr = new Arr(len * 3 / 4 - placeHolders)

  // if there are placeholders, only get up to the last complete 4 chars
  l = placeHolders > 0 ? len - 4 : len

  var L = 0

  for (i = 0, j = 0; i < l; i += 4, j += 3) {
    tmp = (revLookup[b64.charCodeAt(i)] << 18) | (revLookup[b64.charCodeAt(i + 1)] << 12) | (revLookup[b64.charCodeAt(i + 2)] << 6) | revLookup[b64.charCodeAt(i + 3)]
    arr[L++] = (tmp >> 16) & 0xFF
    arr[L++] = (tmp >> 8) & 0xFF
    arr[L++] = tmp & 0xFF
  }

  if (placeHolders === 2) {
    tmp = (revLookup[b64.charCodeAt(i)] << 2) | (revLookup[b64.charCodeAt(i + 1)] >> 4)
    arr[L++] = tmp & 0xFF
  } else if (placeHolders === 1) {
    tmp = (revLookup[b64.charCodeAt(i)] << 10) | (revLookup[b64.charCodeAt(i + 1)] << 4) | (revLookup[b64.charCodeAt(i + 2)] >> 2)
    arr[L++] = (tmp >> 8) & 0xFF
    arr[L++] = tmp & 0xFF
  }

  return arr
}

function tripletToBase64 (num) {
  return lookup[num >> 18 & 0x3F] + lookup[num >> 12 & 0x3F] + lookup[num >> 6 & 0x3F] + lookup[num & 0x3F]
}

function encodeChunk (uint8, start, end) {
  var tmp
  var output = []
  for (var i = start; i < end; i += 3) {
    tmp = (uint8[i] << 16) + (uint8[i + 1] << 8) + (uint8[i + 2])
    output.push(tripletToBase64(tmp))
  }
  return output.join('')
}

function fromByteArray (uint8) {
  var tmp
  var len = uint8.length
  var extraBytes = len % 3 // if we have 1 byte left, pad 2 bytes
  var output = ''
  var parts = []
  var maxChunkLength = 16383 // must be multiple of 3

  // go through the array every three bytes, we'll deal with trailing stuff later
  for (var i = 0, len2 = len - extraBytes; i < len2; i += maxChunkLength) {
    parts.push(encodeChunk(uint8, i, (i + maxChunkLength) > len2 ? len2 : (i + maxChunkLength)))
  }

  // pad the end with zeros, but make sure to not forget the extra bytes
  if (extraBytes === 1) {
    tmp = uint8[len - 1]
    output += lookup[tmp >> 2]
    output += lookup[(tmp << 4) & 0x3F]
    output += '=='
  } else if (extraBytes === 2) {
    tmp = (uint8[len - 2] << 8) + (uint8[len - 1])
    output += lookup[tmp >> 10]
    output += lookup[(tmp >> 4) & 0x3F]
    output += lookup[(tmp << 2) & 0x3F]
    output += '='
  }

  parts.push(output)

  return parts.join('')
}

},{}],2:[function(require,module,exports){

},{}],3:[function(require,module,exports){
/*!
 * The buffer module from node.js, for the browser.
 *
 * @author   Feross Aboukhadijeh <feross@feross.org> <http://feross.org>
 * @license  MIT
 */
/* eslint-disable no-proto */

'use strict'

var base64 = require('base64-js')
var ieee754 = require('ieee754')

exports.Buffer = Buffer
exports.SlowBuffer = SlowBuffer
exports.INSPECT_MAX_BYTES = 50

var K_MAX_LENGTH = 0x7fffffff
exports.kMaxLength = K_MAX_LENGTH

/**
 * If `Buffer.TYPED_ARRAY_SUPPORT`:
 *   === true    Use Uint8Array implementation (fastest)
 *   === false   Print warning and recommend using `buffer` v4.x which has an Object
 *               implementation (most compatible, even IE6)
 *
 * Browsers that support typed arrays are IE 10+, Firefox 4+, Chrome 7+, Safari 5.1+,
 * Opera 11.6+, iOS 4.2+.
 *
 * We report that the browser does not support typed arrays if the are not subclassable
 * using __proto__. Firefox 4-29 lacks support for adding new properties to `Uint8Array`
 * (See: https://bugzilla.mozilla.org/show_bug.cgi?id=695438). IE 10 lacks support
 * for __proto__ and has a buggy typed array implementation.
 */
Buffer.TYPED_ARRAY_SUPPORT = typedArraySupport()

if (!Buffer.TYPED_ARRAY_SUPPORT && typeof console !== 'undefined' &&
    typeof console.error === 'function') {
  console.error(
    'This browser lacks typed array (Uint8Array) support which is required by ' +
    '`buffer` v5.x. Use `buffer` v4.x if you require old browser support.'
  )
}

function typedArraySupport () {
  // Can typed array instances can be augmented?
  try {
    var arr = new Uint8Array(1)
    arr.__proto__ = {__proto__: Uint8Array.prototype, foo: function () { return 42 }}
    return arr.foo() === 42
  } catch (e) {
    return false
  }
}

function createBuffer (length) {
  if (length > K_MAX_LENGTH) {
    throw new RangeError('Invalid typed array length')
  }
  // Return an augmented `Uint8Array` instance
  var buf = new Uint8Array(length)
  buf.__proto__ = Buffer.prototype
  return buf
}

/**
 * The Buffer constructor returns instances of `Uint8Array` that have their
 * prototype changed to `Buffer.prototype`. Furthermore, `Buffer` is a subclass of
 * `Uint8Array`, so the returned instances will have all the node `Buffer` methods
 * and the `Uint8Array` methods. Square bracket notation works as expected -- it
 * returns a single octet.
 *
 * The `Uint8Array` prototype remains unmodified.
 */

function Buffer (arg, encodingOrOffset, length) {
  // Common case.
  if (typeof arg === 'number') {
    if (typeof encodingOrOffset === 'string') {
      throw new Error(
        'If encoding is specified then the first argument must be a string'
      )
    }
    return allocUnsafe(arg)
  }
  return from(arg, encodingOrOffset, length)
}

// Fix subarray() in ES2016. See: https://github.com/feross/buffer/pull/97
if (typeof Symbol !== 'undefined' && Symbol.species &&
    Buffer[Symbol.species] === Buffer) {
  Object.defineProperty(Buffer, Symbol.species, {
    value: null,
    configurable: true,
    enumerable: false,
    writable: false
  })
}

Buffer.poolSize = 8192 // not used by this implementation

function from (value, encodingOrOffset, length) {
  if (typeof value === 'number') {
    throw new TypeError('"value" argument must not be a number')
  }

  if (value instanceof ArrayBuffer) {
    return fromArrayBuffer(value, encodingOrOffset, length)
  }

  if (typeof value === 'string') {
    return fromString(value, encodingOrOffset)
  }

  return fromObject(value)
}

/**
 * Functionally equivalent to Buffer(arg, encoding) but throws a TypeError
 * if value is a number.
 * Buffer.from(str[, encoding])
 * Buffer.from(array)
 * Buffer.from(buffer)
 * Buffer.from(arrayBuffer[, byteOffset[, length]])
 **/
Buffer.from = function (value, encodingOrOffset, length) {
  return from(value, encodingOrOffset, length)
}

// Note: Change prototype *after* Buffer.from is defined to workaround Chrome bug:
// https://github.com/feross/buffer/pull/148
Buffer.prototype.__proto__ = Uint8Array.prototype
Buffer.__proto__ = Uint8Array

function assertSize (size) {
  if (typeof size !== 'number') {
    throw new TypeError('"size" argument must be a number')
  } else if (size < 0) {
    throw new RangeError('"size" argument must not be negative')
  }
}

function alloc (size, fill, encoding) {
  assertSize(size)
  if (size <= 0) {
    return createBuffer(size)
  }
  if (fill !== undefined) {
    // Only pay attention to encoding if it's a string. This
    // prevents accidentally sending in a number that would
    // be interpretted as a start offset.
    return typeof encoding === 'string'
      ? createBuffer(size).fill(fill, encoding)
      : createBuffer(size).fill(fill)
  }
  return createBuffer(size)
}

/**
 * Creates a new filled Buffer instance.
 * alloc(size[, fill[, encoding]])
 **/
Buffer.alloc = function (size, fill, encoding) {
  return alloc(size, fill, encoding)
}

function allocUnsafe (size) {
  assertSize(size)
  return createBuffer(size < 0 ? 0 : checked(size) | 0)
}

/**
 * Equivalent to Buffer(num), by default creates a non-zero-filled Buffer instance.
 * */
Buffer.allocUnsafe = function (size) {
  return allocUnsafe(size)
}
/**
 * Equivalent to SlowBuffer(num), by default creates a non-zero-filled Buffer instance.
 */
Buffer.allocUnsafeSlow = function (size) {
  return allocUnsafe(size)
}

function fromString (string, encoding) {
  if (typeof encoding !== 'string' || encoding === '') {
    encoding = 'utf8'
  }

  if (!Buffer.isEncoding(encoding)) {
    throw new TypeError('"encoding" must be a valid string encoding')
  }

  var length = byteLength(string, encoding) | 0
  var buf = createBuffer(length)

  var actual = buf.write(string, encoding)

  if (actual !== length) {
    // Writing a hex string, for example, that contains invalid characters will
    // cause everything after the first invalid character to be ignored. (e.g.
    // 'abxxcd' will be treated as 'ab')
    buf = buf.slice(0, actual)
  }

  return buf
}

function fromArrayLike (array) {
  var length = array.length < 0 ? 0 : checked(array.length) | 0
  var buf = createBuffer(length)
  for (var i = 0; i < length; i += 1) {
    buf[i] = array[i] & 255
  }
  return buf
}

function fromArrayBuffer (array, byteOffset, length) {
  if (byteOffset < 0 || array.byteLength < byteOffset) {
    throw new RangeError('\'offset\' is out of bounds')
  }

  if (array.byteLength < byteOffset + (length || 0)) {
    throw new RangeError('\'length\' is out of bounds')
  }

  var buf
  if (byteOffset === undefined && length === undefined) {
    buf = new Uint8Array(array)
  } else if (length === undefined) {
    buf = new Uint8Array(array, byteOffset)
  } else {
    buf = new Uint8Array(array, byteOffset, length)
  }

  // Return an augmented `Uint8Array` instance
  buf.__proto__ = Buffer.prototype
  return buf
}

function fromObject (obj) {
  if (Buffer.isBuffer(obj)) {
    var len = checked(obj.length) | 0
    var buf = createBuffer(len)

    if (buf.length === 0) {
      return buf
    }

    obj.copy(buf, 0, 0, len)
    return buf
  }

  if (obj) {
    if (isArrayBufferView(obj) || 'length' in obj) {
      if (typeof obj.length !== 'number' || numberIsNaN(obj.length)) {
        return createBuffer(0)
      }
      return fromArrayLike(obj)
    }

    if (obj.type === 'Buffer' && Array.isArray(obj.data)) {
      return fromArrayLike(obj.data)
    }
  }

  throw new TypeError('First argument must be a string, Buffer, ArrayBuffer, Array, or array-like object.')
}

function checked (length) {
  // Note: cannot use `length < K_MAX_LENGTH` here because that fails when
  // length is NaN (which is otherwise coerced to zero.)
  if (length >= K_MAX_LENGTH) {
    throw new RangeError('Attempt to allocate Buffer larger than maximum ' +
                         'size: 0x' + K_MAX_LENGTH.toString(16) + ' bytes')
  }
  return length | 0
}

function SlowBuffer (length) {
  if (+length != length) { // eslint-disable-line eqeqeq
    length = 0
  }
  return Buffer.alloc(+length)
}

Buffer.isBuffer = function isBuffer (b) {
  return b != null && b._isBuffer === true
}

Buffer.compare = function compare (a, b) {
  if (!Buffer.isBuffer(a) || !Buffer.isBuffer(b)) {
    throw new TypeError('Arguments must be Buffers')
  }

  if (a === b) return 0

  var x = a.length
  var y = b.length

  for (var i = 0, len = Math.min(x, y); i < len; ++i) {
    if (a[i] !== b[i]) {
      x = a[i]
      y = b[i]
      break
    }
  }

  if (x < y) return -1
  if (y < x) return 1
  return 0
}

Buffer.isEncoding = function isEncoding (encoding) {
  switch (String(encoding).toLowerCase()) {
    case 'hex':
    case 'utf8':
    case 'utf-8':
    case 'ascii':
    case 'latin1':
    case 'binary':
    case 'base64':
    case 'ucs2':
    case 'ucs-2':
    case 'utf16le':
    case 'utf-16le':
      return true
    default:
      return false
  }
}

Buffer.concat = function concat (list, length) {
  if (!Array.isArray(list)) {
    throw new TypeError('"list" argument must be an Array of Buffers')
  }

  if (list.length === 0) {
    return Buffer.alloc(0)
  }

  var i
  if (length === undefined) {
    length = 0
    for (i = 0; i < list.length; ++i) {
      length += list[i].length
    }
  }

  var buffer = Buffer.allocUnsafe(length)
  var pos = 0
  for (i = 0; i < list.length; ++i) {
    var buf = list[i]
    if (!Buffer.isBuffer(buf)) {
      throw new TypeError('"list" argument must be an Array of Buffers')
    }
    buf.copy(buffer, pos)
    pos += buf.length
  }
  return buffer
}

function byteLength (string, encoding) {
  if (Buffer.isBuffer(string)) {
    return string.length
  }
  if (isArrayBufferView(string) || string instanceof ArrayBuffer) {
    return string.byteLength
  }
  if (typeof string !== 'string') {
    string = '' + string
  }

  var len = string.length
  if (len === 0) return 0

  // Use a for loop to avoid recursion
  var loweredCase = false
  for (;;) {
    switch (encoding) {
      case 'ascii':
      case 'latin1':
      case 'binary':
        return len
      case 'utf8':
      case 'utf-8':
      case undefined:
        return utf8ToBytes(string).length
      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return len * 2
      case 'hex':
        return len >>> 1
      case 'base64':
        return base64ToBytes(string).length
      default:
        if (loweredCase) return utf8ToBytes(string).length // assume utf8
        encoding = ('' + encoding).toLowerCase()
        loweredCase = true
    }
  }
}
Buffer.byteLength = byteLength

function slowToString (encoding, start, end) {
  var loweredCase = false

  // No need to verify that "this.length <= MAX_UINT32" since it's a read-only
  // property of a typed array.

  // This behaves neither like String nor Uint8Array in that we set start/end
  // to their upper/lower bounds if the value passed is out of range.
  // undefined is handled specially as per ECMA-262 6th Edition,
  // Section 13.3.3.7 Runtime Semantics: KeyedBindingInitialization.
  if (start === undefined || start < 0) {
    start = 0
  }
  // Return early if start > this.length. Done here to prevent potential uint32
  // coercion fail below.
  if (start > this.length) {
    return ''
  }

  if (end === undefined || end > this.length) {
    end = this.length
  }

  if (end <= 0) {
    return ''
  }

  // Force coersion to uint32. This will also coerce falsey/NaN values to 0.
  end >>>= 0
  start >>>= 0

  if (end <= start) {
    return ''
  }

  if (!encoding) encoding = 'utf8'

  while (true) {
    switch (encoding) {
      case 'hex':
        return hexSlice(this, start, end)

      case 'utf8':
      case 'utf-8':
        return utf8Slice(this, start, end)

      case 'ascii':
        return asciiSlice(this, start, end)

      case 'latin1':
      case 'binary':
        return latin1Slice(this, start, end)

      case 'base64':
        return base64Slice(this, start, end)

      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return utf16leSlice(this, start, end)

      default:
        if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
        encoding = (encoding + '').toLowerCase()
        loweredCase = true
    }
  }
}

// This property is used by `Buffer.isBuffer` (and the `is-buffer` npm package)
// to detect a Buffer instance. It's not possible to use `instanceof Buffer`
// reliably in a browserify context because there could be multiple different
// copies of the 'buffer' package in use. This method works even for Buffer
// instances that were created from another copy of the `buffer` package.
// See: https://github.com/feross/buffer/issues/154
Buffer.prototype._isBuffer = true

function swap (b, n, m) {
  var i = b[n]
  b[n] = b[m]
  b[m] = i
}

Buffer.prototype.swap16 = function swap16 () {
  var len = this.length
  if (len % 2 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 16-bits')
  }
  for (var i = 0; i < len; i += 2) {
    swap(this, i, i + 1)
  }
  return this
}

Buffer.prototype.swap32 = function swap32 () {
  var len = this.length
  if (len % 4 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 32-bits')
  }
  for (var i = 0; i < len; i += 4) {
    swap(this, i, i + 3)
    swap(this, i + 1, i + 2)
  }
  return this
}

Buffer.prototype.swap64 = function swap64 () {
  var len = this.length
  if (len % 8 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 64-bits')
  }
  for (var i = 0; i < len; i += 8) {
    swap(this, i, i + 7)
    swap(this, i + 1, i + 6)
    swap(this, i + 2, i + 5)
    swap(this, i + 3, i + 4)
  }
  return this
}

Buffer.prototype.toString = function toString () {
  var length = this.length
  if (length === 0) return ''
  if (arguments.length === 0) return utf8Slice(this, 0, length)
  return slowToString.apply(this, arguments)
}

Buffer.prototype.equals = function equals (b) {
  if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer')
  if (this === b) return true
  return Buffer.compare(this, b) === 0
}

Buffer.prototype.inspect = function inspect () {
  var str = ''
  var max = exports.INSPECT_MAX_BYTES
  if (this.length > 0) {
    str = this.toString('hex', 0, max).match(/.{2}/g).join(' ')
    if (this.length > max) str += ' ... '
  }
  return '<Buffer ' + str + '>'
}

Buffer.prototype.compare = function compare (target, start, end, thisStart, thisEnd) {
  if (!Buffer.isBuffer(target)) {
    throw new TypeError('Argument must be a Buffer')
  }

  if (start === undefined) {
    start = 0
  }
  if (end === undefined) {
    end = target ? target.length : 0
  }
  if (thisStart === undefined) {
    thisStart = 0
  }
  if (thisEnd === undefined) {
    thisEnd = this.length
  }

  if (start < 0 || end > target.length || thisStart < 0 || thisEnd > this.length) {
    throw new RangeError('out of range index')
  }

  if (thisStart >= thisEnd && start >= end) {
    return 0
  }
  if (thisStart >= thisEnd) {
    return -1
  }
  if (start >= end) {
    return 1
  }

  start >>>= 0
  end >>>= 0
  thisStart >>>= 0
  thisEnd >>>= 0

  if (this === target) return 0

  var x = thisEnd - thisStart
  var y = end - start
  var len = Math.min(x, y)

  var thisCopy = this.slice(thisStart, thisEnd)
  var targetCopy = target.slice(start, end)

  for (var i = 0; i < len; ++i) {
    if (thisCopy[i] !== targetCopy[i]) {
      x = thisCopy[i]
      y = targetCopy[i]
      break
    }
  }

  if (x < y) return -1
  if (y < x) return 1
  return 0
}

// Finds either the first index of `val` in `buffer` at offset >= `byteOffset`,
// OR the last index of `val` in `buffer` at offset <= `byteOffset`.
//
// Arguments:
// - buffer - a Buffer to search
// - val - a string, Buffer, or number
// - byteOffset - an index into `buffer`; will be clamped to an int32
// - encoding - an optional encoding, relevant is val is a string
// - dir - true for indexOf, false for lastIndexOf
function bidirectionalIndexOf (buffer, val, byteOffset, encoding, dir) {
  // Empty buffer means no match
  if (buffer.length === 0) return -1

  // Normalize byteOffset
  if (typeof byteOffset === 'string') {
    encoding = byteOffset
    byteOffset = 0
  } else if (byteOffset > 0x7fffffff) {
    byteOffset = 0x7fffffff
  } else if (byteOffset < -0x80000000) {
    byteOffset = -0x80000000
  }
  byteOffset = +byteOffset  // Coerce to Number.
  if (numberIsNaN(byteOffset)) {
    // byteOffset: it it's undefined, null, NaN, "foo", etc, search whole buffer
    byteOffset = dir ? 0 : (buffer.length - 1)
  }

  // Normalize byteOffset: negative offsets start from the end of the buffer
  if (byteOffset < 0) byteOffset = buffer.length + byteOffset
  if (byteOffset >= buffer.length) {
    if (dir) return -1
    else byteOffset = buffer.length - 1
  } else if (byteOffset < 0) {
    if (dir) byteOffset = 0
    else return -1
  }

  // Normalize val
  if (typeof val === 'string') {
    val = Buffer.from(val, encoding)
  }

  // Finally, search either indexOf (if dir is true) or lastIndexOf
  if (Buffer.isBuffer(val)) {
    // Special case: looking for empty string/buffer always fails
    if (val.length === 0) {
      return -1
    }
    return arrayIndexOf(buffer, val, byteOffset, encoding, dir)
  } else if (typeof val === 'number') {
    val = val & 0xFF // Search for a byte value [0-255]
    if (typeof Uint8Array.prototype.indexOf === 'function') {
      if (dir) {
        return Uint8Array.prototype.indexOf.call(buffer, val, byteOffset)
      } else {
        return Uint8Array.prototype.lastIndexOf.call(buffer, val, byteOffset)
      }
    }
    return arrayIndexOf(buffer, [ val ], byteOffset, encoding, dir)
  }

  throw new TypeError('val must be string, number or Buffer')
}

function arrayIndexOf (arr, val, byteOffset, encoding, dir) {
  var indexSize = 1
  var arrLength = arr.length
  var valLength = val.length

  if (encoding !== undefined) {
    encoding = String(encoding).toLowerCase()
    if (encoding === 'ucs2' || encoding === 'ucs-2' ||
        encoding === 'utf16le' || encoding === 'utf-16le') {
      if (arr.length < 2 || val.length < 2) {
        return -1
      }
      indexSize = 2
      arrLength /= 2
      valLength /= 2
      byteOffset /= 2
    }
  }

  function read (buf, i) {
    if (indexSize === 1) {
      return buf[i]
    } else {
      return buf.readUInt16BE(i * indexSize)
    }
  }

  var i
  if (dir) {
    var foundIndex = -1
    for (i = byteOffset; i < arrLength; i++) {
      if (read(arr, i) === read(val, foundIndex === -1 ? 0 : i - foundIndex)) {
        if (foundIndex === -1) foundIndex = i
        if (i - foundIndex + 1 === valLength) return foundIndex * indexSize
      } else {
        if (foundIndex !== -1) i -= i - foundIndex
        foundIndex = -1
      }
    }
  } else {
    if (byteOffset + valLength > arrLength) byteOffset = arrLength - valLength
    for (i = byteOffset; i >= 0; i--) {
      var found = true
      for (var j = 0; j < valLength; j++) {
        if (read(arr, i + j) !== read(val, j)) {
          found = false
          break
        }
      }
      if (found) return i
    }
  }

  return -1
}

Buffer.prototype.includes = function includes (val, byteOffset, encoding) {
  return this.indexOf(val, byteOffset, encoding) !== -1
}

Buffer.prototype.indexOf = function indexOf (val, byteOffset, encoding) {
  return bidirectionalIndexOf(this, val, byteOffset, encoding, true)
}

Buffer.prototype.lastIndexOf = function lastIndexOf (val, byteOffset, encoding) {
  return bidirectionalIndexOf(this, val, byteOffset, encoding, false)
}

function hexWrite (buf, string, offset, length) {
  offset = Number(offset) || 0
  var remaining = buf.length - offset
  if (!length) {
    length = remaining
  } else {
    length = Number(length)
    if (length > remaining) {
      length = remaining
    }
  }

  // must be an even number of digits
  var strLen = string.length
  if (strLen % 2 !== 0) throw new TypeError('Invalid hex string')

  if (length > strLen / 2) {
    length = strLen / 2
  }
  for (var i = 0; i < length; ++i) {
    var parsed = parseInt(string.substr(i * 2, 2), 16)
    if (numberIsNaN(parsed)) return i
    buf[offset + i] = parsed
  }
  return i
}

function utf8Write (buf, string, offset, length) {
  return blitBuffer(utf8ToBytes(string, buf.length - offset), buf, offset, length)
}

function asciiWrite (buf, string, offset, length) {
  return blitBuffer(asciiToBytes(string), buf, offset, length)
}

function latin1Write (buf, string, offset, length) {
  return asciiWrite(buf, string, offset, length)
}

function base64Write (buf, string, offset, length) {
  return blitBuffer(base64ToBytes(string), buf, offset, length)
}

function ucs2Write (buf, string, offset, length) {
  return blitBuffer(utf16leToBytes(string, buf.length - offset), buf, offset, length)
}

Buffer.prototype.write = function write (string, offset, length, encoding) {
  // Buffer#write(string)
  if (offset === undefined) {
    encoding = 'utf8'
    length = this.length
    offset = 0
  // Buffer#write(string, encoding)
  } else if (length === undefined && typeof offset === 'string') {
    encoding = offset
    length = this.length
    offset = 0
  // Buffer#write(string, offset[, length][, encoding])
  } else if (isFinite(offset)) {
    offset = offset >>> 0
    if (isFinite(length)) {
      length = length >>> 0
      if (encoding === undefined) encoding = 'utf8'
    } else {
      encoding = length
      length = undefined
    }
  } else {
    throw new Error(
      'Buffer.write(string, encoding, offset[, length]) is no longer supported'
    )
  }

  var remaining = this.length - offset
  if (length === undefined || length > remaining) length = remaining

  if ((string.length > 0 && (length < 0 || offset < 0)) || offset > this.length) {
    throw new RangeError('Attempt to write outside buffer bounds')
  }

  if (!encoding) encoding = 'utf8'

  var loweredCase = false
  for (;;) {
    switch (encoding) {
      case 'hex':
        return hexWrite(this, string, offset, length)

      case 'utf8':
      case 'utf-8':
        return utf8Write(this, string, offset, length)

      case 'ascii':
        return asciiWrite(this, string, offset, length)

      case 'latin1':
      case 'binary':
        return latin1Write(this, string, offset, length)

      case 'base64':
        // Warning: maxLength not taken into account in base64Write
        return base64Write(this, string, offset, length)

      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return ucs2Write(this, string, offset, length)

      default:
        if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
        encoding = ('' + encoding).toLowerCase()
        loweredCase = true
    }
  }
}

Buffer.prototype.toJSON = function toJSON () {
  return {
    type: 'Buffer',
    data: Array.prototype.slice.call(this._arr || this, 0)
  }
}

function base64Slice (buf, start, end) {
  if (start === 0 && end === buf.length) {
    return base64.fromByteArray(buf)
  } else {
    return base64.fromByteArray(buf.slice(start, end))
  }
}

function utf8Slice (buf, start, end) {
  end = Math.min(buf.length, end)
  var res = []

  var i = start
  while (i < end) {
    var firstByte = buf[i]
    var codePoint = null
    var bytesPerSequence = (firstByte > 0xEF) ? 4
      : (firstByte > 0xDF) ? 3
      : (firstByte > 0xBF) ? 2
      : 1

    if (i + bytesPerSequence <= end) {
      var secondByte, thirdByte, fourthByte, tempCodePoint

      switch (bytesPerSequence) {
        case 1:
          if (firstByte < 0x80) {
            codePoint = firstByte
          }
          break
        case 2:
          secondByte = buf[i + 1]
          if ((secondByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0x1F) << 0x6 | (secondByte & 0x3F)
            if (tempCodePoint > 0x7F) {
              codePoint = tempCodePoint
            }
          }
          break
        case 3:
          secondByte = buf[i + 1]
          thirdByte = buf[i + 2]
          if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0xF) << 0xC | (secondByte & 0x3F) << 0x6 | (thirdByte & 0x3F)
            if (tempCodePoint > 0x7FF && (tempCodePoint < 0xD800 || tempCodePoint > 0xDFFF)) {
              codePoint = tempCodePoint
            }
          }
          break
        case 4:
          secondByte = buf[i + 1]
          thirdByte = buf[i + 2]
          fourthByte = buf[i + 3]
          if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80 && (fourthByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0xF) << 0x12 | (secondByte & 0x3F) << 0xC | (thirdByte & 0x3F) << 0x6 | (fourthByte & 0x3F)
            if (tempCodePoint > 0xFFFF && tempCodePoint < 0x110000) {
              codePoint = tempCodePoint
            }
          }
      }
    }

    if (codePoint === null) {
      // we did not generate a valid codePoint so insert a
      // replacement char (U+FFFD) and advance only 1 byte
      codePoint = 0xFFFD
      bytesPerSequence = 1
    } else if (codePoint > 0xFFFF) {
      // encode to utf16 (surrogate pair dance)
      codePoint -= 0x10000
      res.push(codePoint >>> 10 & 0x3FF | 0xD800)
      codePoint = 0xDC00 | codePoint & 0x3FF
    }

    res.push(codePoint)
    i += bytesPerSequence
  }

  return decodeCodePointsArray(res)
}

// Based on http://stackoverflow.com/a/22747272/680742, the browser with
// the lowest limit is Chrome, with 0x10000 args.
// We go 1 magnitude less, for safety
var MAX_ARGUMENTS_LENGTH = 0x1000

function decodeCodePointsArray (codePoints) {
  var len = codePoints.length
  if (len <= MAX_ARGUMENTS_LENGTH) {
    return String.fromCharCode.apply(String, codePoints) // avoid extra slice()
  }

  // Decode in chunks to avoid "call stack size exceeded".
  var res = ''
  var i = 0
  while (i < len) {
    res += String.fromCharCode.apply(
      String,
      codePoints.slice(i, i += MAX_ARGUMENTS_LENGTH)
    )
  }
  return res
}

function asciiSlice (buf, start, end) {
  var ret = ''
  end = Math.min(buf.length, end)

  for (var i = start; i < end; ++i) {
    ret += String.fromCharCode(buf[i] & 0x7F)
  }
  return ret
}

function latin1Slice (buf, start, end) {
  var ret = ''
  end = Math.min(buf.length, end)

  for (var i = start; i < end; ++i) {
    ret += String.fromCharCode(buf[i])
  }
  return ret
}

function hexSlice (buf, start, end) {
  var len = buf.length

  if (!start || start < 0) start = 0
  if (!end || end < 0 || end > len) end = len

  var out = ''
  for (var i = start; i < end; ++i) {
    out += toHex(buf[i])
  }
  return out
}

function utf16leSlice (buf, start, end) {
  var bytes = buf.slice(start, end)
  var res = ''
  for (var i = 0; i < bytes.length; i += 2) {
    res += String.fromCharCode(bytes[i] + (bytes[i + 1] * 256))
  }
  return res
}

Buffer.prototype.slice = function slice (start, end) {
  var len = this.length
  start = ~~start
  end = end === undefined ? len : ~~end

  if (start < 0) {
    start += len
    if (start < 0) start = 0
  } else if (start > len) {
    start = len
  }

  if (end < 0) {
    end += len
    if (end < 0) end = 0
  } else if (end > len) {
    end = len
  }

  if (end < start) end = start

  var newBuf = this.subarray(start, end)
  // Return an augmented `Uint8Array` instance
  newBuf.__proto__ = Buffer.prototype
  return newBuf
}

/*
 * Need to make sure that buffer isn't trying to write out of bounds.
 */
function checkOffset (offset, ext, length) {
  if ((offset % 1) !== 0 || offset < 0) throw new RangeError('offset is not uint')
  if (offset + ext > length) throw new RangeError('Trying to access beyond buffer length')
}

Buffer.prototype.readUIntLE = function readUIntLE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) checkOffset(offset, byteLength, this.length)

  var val = this[offset]
  var mul = 1
  var i = 0
  while (++i < byteLength && (mul *= 0x100)) {
    val += this[offset + i] * mul
  }

  return val
}

Buffer.prototype.readUIntBE = function readUIntBE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) {
    checkOffset(offset, byteLength, this.length)
  }

  var val = this[offset + --byteLength]
  var mul = 1
  while (byteLength > 0 && (mul *= 0x100)) {
    val += this[offset + --byteLength] * mul
  }

  return val
}

Buffer.prototype.readUInt8 = function readUInt8 (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 1, this.length)
  return this[offset]
}

Buffer.prototype.readUInt16LE = function readUInt16LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  return this[offset] | (this[offset + 1] << 8)
}

Buffer.prototype.readUInt16BE = function readUInt16BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  return (this[offset] << 8) | this[offset + 1]
}

Buffer.prototype.readUInt32LE = function readUInt32LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return ((this[offset]) |
      (this[offset + 1] << 8) |
      (this[offset + 2] << 16)) +
      (this[offset + 3] * 0x1000000)
}

Buffer.prototype.readUInt32BE = function readUInt32BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return (this[offset] * 0x1000000) +
    ((this[offset + 1] << 16) |
    (this[offset + 2] << 8) |
    this[offset + 3])
}

Buffer.prototype.readIntLE = function readIntLE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) checkOffset(offset, byteLength, this.length)

  var val = this[offset]
  var mul = 1
  var i = 0
  while (++i < byteLength && (mul *= 0x100)) {
    val += this[offset + i] * mul
  }
  mul *= 0x80

  if (val >= mul) val -= Math.pow(2, 8 * byteLength)

  return val
}

Buffer.prototype.readIntBE = function readIntBE (offset, byteLength, noAssert) {
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) checkOffset(offset, byteLength, this.length)

  var i = byteLength
  var mul = 1
  var val = this[offset + --i]
  while (i > 0 && (mul *= 0x100)) {
    val += this[offset + --i] * mul
  }
  mul *= 0x80

  if (val >= mul) val -= Math.pow(2, 8 * byteLength)

  return val
}

Buffer.prototype.readInt8 = function readInt8 (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 1, this.length)
  if (!(this[offset] & 0x80)) return (this[offset])
  return ((0xff - this[offset] + 1) * -1)
}

Buffer.prototype.readInt16LE = function readInt16LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  var val = this[offset] | (this[offset + 1] << 8)
  return (val & 0x8000) ? val | 0xFFFF0000 : val
}

Buffer.prototype.readInt16BE = function readInt16BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 2, this.length)
  var val = this[offset + 1] | (this[offset] << 8)
  return (val & 0x8000) ? val | 0xFFFF0000 : val
}

Buffer.prototype.readInt32LE = function readInt32LE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return (this[offset]) |
    (this[offset + 1] << 8) |
    (this[offset + 2] << 16) |
    (this[offset + 3] << 24)
}

Buffer.prototype.readInt32BE = function readInt32BE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)

  return (this[offset] << 24) |
    (this[offset + 1] << 16) |
    (this[offset + 2] << 8) |
    (this[offset + 3])
}

Buffer.prototype.readFloatLE = function readFloatLE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)
  return ieee754.read(this, offset, true, 23, 4)
}

Buffer.prototype.readFloatBE = function readFloatBE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 4, this.length)
  return ieee754.read(this, offset, false, 23, 4)
}

Buffer.prototype.readDoubleLE = function readDoubleLE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 8, this.length)
  return ieee754.read(this, offset, true, 52, 8)
}

Buffer.prototype.readDoubleBE = function readDoubleBE (offset, noAssert) {
  offset = offset >>> 0
  if (!noAssert) checkOffset(offset, 8, this.length)
  return ieee754.read(this, offset, false, 52, 8)
}

function checkInt (buf, value, offset, ext, max, min) {
  if (!Buffer.isBuffer(buf)) throw new TypeError('"buffer" argument must be a Buffer instance')
  if (value > max || value < min) throw new RangeError('"value" argument is out of bounds')
  if (offset + ext > buf.length) throw new RangeError('Index out of range')
}

Buffer.prototype.writeUIntLE = function writeUIntLE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) {
    var maxBytes = Math.pow(2, 8 * byteLength) - 1
    checkInt(this, value, offset, byteLength, maxBytes, 0)
  }

  var mul = 1
  var i = 0
  this[offset] = value & 0xFF
  while (++i < byteLength && (mul *= 0x100)) {
    this[offset + i] = (value / mul) & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeUIntBE = function writeUIntBE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  byteLength = byteLength >>> 0
  if (!noAssert) {
    var maxBytes = Math.pow(2, 8 * byteLength) - 1
    checkInt(this, value, offset, byteLength, maxBytes, 0)
  }

  var i = byteLength - 1
  var mul = 1
  this[offset + i] = value & 0xFF
  while (--i >= 0 && (mul *= 0x100)) {
    this[offset + i] = (value / mul) & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeUInt8 = function writeUInt8 (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 1, 0xff, 0)
  this[offset] = (value & 0xff)
  return offset + 1
}

Buffer.prototype.writeUInt16LE = function writeUInt16LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0)
  this[offset] = (value & 0xff)
  this[offset + 1] = (value >>> 8)
  return offset + 2
}

Buffer.prototype.writeUInt16BE = function writeUInt16BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0)
  this[offset] = (value >>> 8)
  this[offset + 1] = (value & 0xff)
  return offset + 2
}

Buffer.prototype.writeUInt32LE = function writeUInt32LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0)
  this[offset + 3] = (value >>> 24)
  this[offset + 2] = (value >>> 16)
  this[offset + 1] = (value >>> 8)
  this[offset] = (value & 0xff)
  return offset + 4
}

Buffer.prototype.writeUInt32BE = function writeUInt32BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0)
  this[offset] = (value >>> 24)
  this[offset + 1] = (value >>> 16)
  this[offset + 2] = (value >>> 8)
  this[offset + 3] = (value & 0xff)
  return offset + 4
}

Buffer.prototype.writeIntLE = function writeIntLE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    var limit = Math.pow(2, (8 * byteLength) - 1)

    checkInt(this, value, offset, byteLength, limit - 1, -limit)
  }

  var i = 0
  var mul = 1
  var sub = 0
  this[offset] = value & 0xFF
  while (++i < byteLength && (mul *= 0x100)) {
    if (value < 0 && sub === 0 && this[offset + i - 1] !== 0) {
      sub = 1
    }
    this[offset + i] = ((value / mul) >> 0) - sub & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeIntBE = function writeIntBE (value, offset, byteLength, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    var limit = Math.pow(2, (8 * byteLength) - 1)

    checkInt(this, value, offset, byteLength, limit - 1, -limit)
  }

  var i = byteLength - 1
  var mul = 1
  var sub = 0
  this[offset + i] = value & 0xFF
  while (--i >= 0 && (mul *= 0x100)) {
    if (value < 0 && sub === 0 && this[offset + i + 1] !== 0) {
      sub = 1
    }
    this[offset + i] = ((value / mul) >> 0) - sub & 0xFF
  }

  return offset + byteLength
}

Buffer.prototype.writeInt8 = function writeInt8 (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 1, 0x7f, -0x80)
  if (value < 0) value = 0xff + value + 1
  this[offset] = (value & 0xff)
  return offset + 1
}

Buffer.prototype.writeInt16LE = function writeInt16LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000)
  this[offset] = (value & 0xff)
  this[offset + 1] = (value >>> 8)
  return offset + 2
}

Buffer.prototype.writeInt16BE = function writeInt16BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000)
  this[offset] = (value >>> 8)
  this[offset + 1] = (value & 0xff)
  return offset + 2
}

Buffer.prototype.writeInt32LE = function writeInt32LE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000)
  this[offset] = (value & 0xff)
  this[offset + 1] = (value >>> 8)
  this[offset + 2] = (value >>> 16)
  this[offset + 3] = (value >>> 24)
  return offset + 4
}

Buffer.prototype.writeInt32BE = function writeInt32BE (value, offset, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000)
  if (value < 0) value = 0xffffffff + value + 1
  this[offset] = (value >>> 24)
  this[offset + 1] = (value >>> 16)
  this[offset + 2] = (value >>> 8)
  this[offset + 3] = (value & 0xff)
  return offset + 4
}

function checkIEEE754 (buf, value, offset, ext, max, min) {
  if (offset + ext > buf.length) throw new RangeError('Index out of range')
  if (offset < 0) throw new RangeError('Index out of range')
}

function writeFloat (buf, value, offset, littleEndian, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    checkIEEE754(buf, value, offset, 4, 3.4028234663852886e+38, -3.4028234663852886e+38)
  }
  ieee754.write(buf, value, offset, littleEndian, 23, 4)
  return offset + 4
}

Buffer.prototype.writeFloatLE = function writeFloatLE (value, offset, noAssert) {
  return writeFloat(this, value, offset, true, noAssert)
}

Buffer.prototype.writeFloatBE = function writeFloatBE (value, offset, noAssert) {
  return writeFloat(this, value, offset, false, noAssert)
}

function writeDouble (buf, value, offset, littleEndian, noAssert) {
  value = +value
  offset = offset >>> 0
  if (!noAssert) {
    checkIEEE754(buf, value, offset, 8, 1.7976931348623157E+308, -1.7976931348623157E+308)
  }
  ieee754.write(buf, value, offset, littleEndian, 52, 8)
  return offset + 8
}

Buffer.prototype.writeDoubleLE = function writeDoubleLE (value, offset, noAssert) {
  return writeDouble(this, value, offset, true, noAssert)
}

Buffer.prototype.writeDoubleBE = function writeDoubleBE (value, offset, noAssert) {
  return writeDouble(this, value, offset, false, noAssert)
}

// copy(targetBuffer, targetStart=0, sourceStart=0, sourceEnd=buffer.length)
Buffer.prototype.copy = function copy (target, targetStart, start, end) {
  if (!start) start = 0
  if (!end && end !== 0) end = this.length
  if (targetStart >= target.length) targetStart = target.length
  if (!targetStart) targetStart = 0
  if (end > 0 && end < start) end = start

  // Copy 0 bytes; we're done
  if (end === start) return 0
  if (target.length === 0 || this.length === 0) return 0

  // Fatal error conditions
  if (targetStart < 0) {
    throw new RangeError('targetStart out of bounds')
  }
  if (start < 0 || start >= this.length) throw new RangeError('sourceStart out of bounds')
  if (end < 0) throw new RangeError('sourceEnd out of bounds')

  // Are we oob?
  if (end > this.length) end = this.length
  if (target.length - targetStart < end - start) {
    end = target.length - targetStart + start
  }

  var len = end - start
  var i

  if (this === target && start < targetStart && targetStart < end) {
    // descending copy from end
    for (i = len - 1; i >= 0; --i) {
      target[i + targetStart] = this[i + start]
    }
  } else if (len < 1000) {
    // ascending copy from start
    for (i = 0; i < len; ++i) {
      target[i + targetStart] = this[i + start]
    }
  } else {
    Uint8Array.prototype.set.call(
      target,
      this.subarray(start, start + len),
      targetStart
    )
  }

  return len
}

// Usage:
//    buffer.fill(number[, offset[, end]])
//    buffer.fill(buffer[, offset[, end]])
//    buffer.fill(string[, offset[, end]][, encoding])
Buffer.prototype.fill = function fill (val, start, end, encoding) {
  // Handle string cases:
  if (typeof val === 'string') {
    if (typeof start === 'string') {
      encoding = start
      start = 0
      end = this.length
    } else if (typeof end === 'string') {
      encoding = end
      end = this.length
    }
    if (val.length === 1) {
      var code = val.charCodeAt(0)
      if (code < 256) {
        val = code
      }
    }
    if (encoding !== undefined && typeof encoding !== 'string') {
      throw new TypeError('encoding must be a string')
    }
    if (typeof encoding === 'string' && !Buffer.isEncoding(encoding)) {
      throw new TypeError('Unknown encoding: ' + encoding)
    }
  } else if (typeof val === 'number') {
    val = val & 255
  }

  // Invalid ranges are not set to a default, so can range check early.
  if (start < 0 || this.length < start || this.length < end) {
    throw new RangeError('Out of range index')
  }

  if (end <= start) {
    return this
  }

  start = start >>> 0
  end = end === undefined ? this.length : end >>> 0

  if (!val) val = 0

  var i
  if (typeof val === 'number') {
    for (i = start; i < end; ++i) {
      this[i] = val
    }
  } else {
    var bytes = Buffer.isBuffer(val)
      ? val
      : new Buffer(val, encoding)
    var len = bytes.length
    for (i = 0; i < end - start; ++i) {
      this[i + start] = bytes[i % len]
    }
  }

  return this
}

// HELPER FUNCTIONS
// ================

var INVALID_BASE64_RE = /[^+/0-9A-Za-z-_]/g

function base64clean (str) {
  // Node strips out invalid characters like \n and \t from the string, base64-js does not
  str = str.trim().replace(INVALID_BASE64_RE, '')
  // Node converts strings with length < 2 to ''
  if (str.length < 2) return ''
  // Node allows for non-padded base64 strings (missing trailing ===), base64-js does not
  while (str.length % 4 !== 0) {
    str = str + '='
  }
  return str
}

function toHex (n) {
  if (n < 16) return '0' + n.toString(16)
  return n.toString(16)
}

function utf8ToBytes (string, units) {
  units = units || Infinity
  var codePoint
  var length = string.length
  var leadSurrogate = null
  var bytes = []

  for (var i = 0; i < length; ++i) {
    codePoint = string.charCodeAt(i)

    // is surrogate component
    if (codePoint > 0xD7FF && codePoint < 0xE000) {
      // last char was a lead
      if (!leadSurrogate) {
        // no lead yet
        if (codePoint > 0xDBFF) {
          // unexpected trail
          if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
          continue
        } else if (i + 1 === length) {
          // unpaired lead
          if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
          continue
        }

        // valid lead
        leadSurrogate = codePoint

        continue
      }

      // 2 leads in a row
      if (codePoint < 0xDC00) {
        if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
        leadSurrogate = codePoint
        continue
      }

      // valid surrogate pair
      codePoint = (leadSurrogate - 0xD800 << 10 | codePoint - 0xDC00) + 0x10000
    } else if (leadSurrogate) {
      // valid bmp char, but last char was a lead
      if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD)
    }

    leadSurrogate = null

    // encode utf8
    if (codePoint < 0x80) {
      if ((units -= 1) < 0) break
      bytes.push(codePoint)
    } else if (codePoint < 0x800) {
      if ((units -= 2) < 0) break
      bytes.push(
        codePoint >> 0x6 | 0xC0,
        codePoint & 0x3F | 0x80
      )
    } else if (codePoint < 0x10000) {
      if ((units -= 3) < 0) break
      bytes.push(
        codePoint >> 0xC | 0xE0,
        codePoint >> 0x6 & 0x3F | 0x80,
        codePoint & 0x3F | 0x80
      )
    } else if (codePoint < 0x110000) {
      if ((units -= 4) < 0) break
      bytes.push(
        codePoint >> 0x12 | 0xF0,
        codePoint >> 0xC & 0x3F | 0x80,
        codePoint >> 0x6 & 0x3F | 0x80,
        codePoint & 0x3F | 0x80
      )
    } else {
      throw new Error('Invalid code point')
    }
  }

  return bytes
}

function asciiToBytes (str) {
  var byteArray = []
  for (var i = 0; i < str.length; ++i) {
    // Node's code seems to be doing this and not & 0x7F..
    byteArray.push(str.charCodeAt(i) & 0xFF)
  }
  return byteArray
}

function utf16leToBytes (str, units) {
  var c, hi, lo
  var byteArray = []
  for (var i = 0; i < str.length; ++i) {
    if ((units -= 2) < 0) break

    c = str.charCodeAt(i)
    hi = c >> 8
    lo = c % 256
    byteArray.push(lo)
    byteArray.push(hi)
  }

  return byteArray
}

function base64ToBytes (str) {
  return base64.toByteArray(base64clean(str))
}

function blitBuffer (src, dst, offset, length) {
  for (var i = 0; i < length; ++i) {
    if ((i + offset >= dst.length) || (i >= src.length)) break
    dst[i + offset] = src[i]
  }
  return i
}

// Node 0.10 supports `ArrayBuffer` but lacks `ArrayBuffer.isView`
function isArrayBufferView (obj) {
  return (typeof ArrayBuffer.isView === 'function') && ArrayBuffer.isView(obj)
}

function numberIsNaN (obj) {
  return obj !== obj // eslint-disable-line no-self-compare
}

},{"base64-js":1,"ieee754":5}],4:[function(require,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

function EventEmitter() {
  this._events = this._events || {};
  this._maxListeners = this._maxListeners || undefined;
}
module.exports = EventEmitter;

// Backwards-compat with node 0.10.x
EventEmitter.EventEmitter = EventEmitter;

EventEmitter.prototype._events = undefined;
EventEmitter.prototype._maxListeners = undefined;

// By default EventEmitters will print a warning if more than 10 listeners are
// added to it. This is a useful default which helps finding memory leaks.
EventEmitter.defaultMaxListeners = 10;

// Obviously not all Emitters should be limited to 10. This function allows
// that to be increased. Set to zero for unlimited.
EventEmitter.prototype.setMaxListeners = function(n) {
  if (!isNumber(n) || n < 0 || isNaN(n))
    throw TypeError('n must be a positive number');
  this._maxListeners = n;
  return this;
};

EventEmitter.prototype.emit = function(type) {
  var er, handler, len, args, i, listeners;

  if (!this._events)
    this._events = {};

  // If there is no 'error' event listener then throw.
  if (type === 'error') {
    if (!this._events.error ||
        (isObject(this._events.error) && !this._events.error.length)) {
      er = arguments[1];
      if (er instanceof Error) {
        throw er; // Unhandled 'error' event
      } else {
        // At least give some kind of context to the user
        var err = new Error('Uncaught, unspecified "error" event. (' + er + ')');
        err.context = er;
        throw err;
      }
    }
  }

  handler = this._events[type];

  if (isUndefined(handler))
    return false;

  if (isFunction(handler)) {
    switch (arguments.length) {
      // fast cases
      case 1:
        handler.call(this);
        break;
      case 2:
        handler.call(this, arguments[1]);
        break;
      case 3:
        handler.call(this, arguments[1], arguments[2]);
        break;
      // slower
      default:
        args = Array.prototype.slice.call(arguments, 1);
        handler.apply(this, args);
    }
  } else if (isObject(handler)) {
    args = Array.prototype.slice.call(arguments, 1);
    listeners = handler.slice();
    len = listeners.length;
    for (i = 0; i < len; i++)
      listeners[i].apply(this, args);
  }

  return true;
};

EventEmitter.prototype.addListener = function(type, listener) {
  var m;

  if (!isFunction(listener))
    throw TypeError('listener must be a function');

  if (!this._events)
    this._events = {};

  // To avoid recursion in the case that type === "newListener"! Before
  // adding it to the listeners, first emit "newListener".
  if (this._events.newListener)
    this.emit('newListener', type,
              isFunction(listener.listener) ?
              listener.listener : listener);

  if (!this._events[type])
    // Optimize the case of one listener. Don't need the extra array object.
    this._events[type] = listener;
  else if (isObject(this._events[type]))
    // If we've already got an array, just append.
    this._events[type].push(listener);
  else
    // Adding the second element, need to change to array.
    this._events[type] = [this._events[type], listener];

  // Check for listener leak
  if (isObject(this._events[type]) && !this._events[type].warned) {
    if (!isUndefined(this._maxListeners)) {
      m = this._maxListeners;
    } else {
      m = EventEmitter.defaultMaxListeners;
    }

    if (m && m > 0 && this._events[type].length > m) {
      this._events[type].warned = true;
      console.error('(node) warning: possible EventEmitter memory ' +
                    'leak detected. %d listeners added. ' +
                    'Use emitter.setMaxListeners() to increase limit.',
                    this._events[type].length);
      if (typeof console.trace === 'function') {
        // not supported in IE 10
        console.trace();
      }
    }
  }

  return this;
};

EventEmitter.prototype.on = EventEmitter.prototype.addListener;

EventEmitter.prototype.once = function(type, listener) {
  if (!isFunction(listener))
    throw TypeError('listener must be a function');

  var fired = false;

  function g() {
    this.removeListener(type, g);

    if (!fired) {
      fired = true;
      listener.apply(this, arguments);
    }
  }

  g.listener = listener;
  this.on(type, g);

  return this;
};

// emits a 'removeListener' event iff the listener was removed
EventEmitter.prototype.removeListener = function(type, listener) {
  var list, position, length, i;

  if (!isFunction(listener))
    throw TypeError('listener must be a function');

  if (!this._events || !this._events[type])
    return this;

  list = this._events[type];
  length = list.length;
  position = -1;

  if (list === listener ||
      (isFunction(list.listener) && list.listener === listener)) {
    delete this._events[type];
    if (this._events.removeListener)
      this.emit('removeListener', type, listener);

  } else if (isObject(list)) {
    for (i = length; i-- > 0;) {
      if (list[i] === listener ||
          (list[i].listener && list[i].listener === listener)) {
        position = i;
        break;
      }
    }

    if (position < 0)
      return this;

    if (list.length === 1) {
      list.length = 0;
      delete this._events[type];
    } else {
      list.splice(position, 1);
    }

    if (this._events.removeListener)
      this.emit('removeListener', type, listener);
  }

  return this;
};

EventEmitter.prototype.removeAllListeners = function(type) {
  var key, listeners;

  if (!this._events)
    return this;

  // not listening for removeListener, no need to emit
  if (!this._events.removeListener) {
    if (arguments.length === 0)
      this._events = {};
    else if (this._events[type])
      delete this._events[type];
    return this;
  }

  // emit removeListener for all listeners on all events
  if (arguments.length === 0) {
    for (key in this._events) {
      if (key === 'removeListener') continue;
      this.removeAllListeners(key);
    }
    this.removeAllListeners('removeListener');
    this._events = {};
    return this;
  }

  listeners = this._events[type];

  if (isFunction(listeners)) {
    this.removeListener(type, listeners);
  } else if (listeners) {
    // LIFO order
    while (listeners.length)
      this.removeListener(type, listeners[listeners.length - 1]);
  }
  delete this._events[type];

  return this;
};

EventEmitter.prototype.listeners = function(type) {
  var ret;
  if (!this._events || !this._events[type])
    ret = [];
  else if (isFunction(this._events[type]))
    ret = [this._events[type]];
  else
    ret = this._events[type].slice();
  return ret;
};

EventEmitter.prototype.listenerCount = function(type) {
  if (this._events) {
    var evlistener = this._events[type];

    if (isFunction(evlistener))
      return 1;
    else if (evlistener)
      return evlistener.length;
  }
  return 0;
};

EventEmitter.listenerCount = function(emitter, type) {
  return emitter.listenerCount(type);
};

function isFunction(arg) {
  return typeof arg === 'function';
}

function isNumber(arg) {
  return typeof arg === 'number';
}

function isObject(arg) {
  return typeof arg === 'object' && arg !== null;
}

function isUndefined(arg) {
  return arg === void 0;
}

},{}],5:[function(require,module,exports){
exports.read = function (buffer, offset, isLE, mLen, nBytes) {
  var e, m
  var eLen = nBytes * 8 - mLen - 1
  var eMax = (1 << eLen) - 1
  var eBias = eMax >> 1
  var nBits = -7
  var i = isLE ? (nBytes - 1) : 0
  var d = isLE ? -1 : 1
  var s = buffer[offset + i]

  i += d

  e = s & ((1 << (-nBits)) - 1)
  s >>= (-nBits)
  nBits += eLen
  for (; nBits > 0; e = e * 256 + buffer[offset + i], i += d, nBits -= 8) {}

  m = e & ((1 << (-nBits)) - 1)
  e >>= (-nBits)
  nBits += mLen
  for (; nBits > 0; m = m * 256 + buffer[offset + i], i += d, nBits -= 8) {}

  if (e === 0) {
    e = 1 - eBias
  } else if (e === eMax) {
    return m ? NaN : ((s ? -1 : 1) * Infinity)
  } else {
    m = m + Math.pow(2, mLen)
    e = e - eBias
  }
  return (s ? -1 : 1) * m * Math.pow(2, e - mLen)
}

exports.write = function (buffer, value, offset, isLE, mLen, nBytes) {
  var e, m, c
  var eLen = nBytes * 8 - mLen - 1
  var eMax = (1 << eLen) - 1
  var eBias = eMax >> 1
  var rt = (mLen === 23 ? Math.pow(2, -24) - Math.pow(2, -77) : 0)
  var i = isLE ? 0 : (nBytes - 1)
  var d = isLE ? 1 : -1
  var s = value < 0 || (value === 0 && 1 / value < 0) ? 1 : 0

  value = Math.abs(value)

  if (isNaN(value) || value === Infinity) {
    m = isNaN(value) ? 1 : 0
    e = eMax
  } else {
    e = Math.floor(Math.log(value) / Math.LN2)
    if (value * (c = Math.pow(2, -e)) < 1) {
      e--
      c *= 2
    }
    if (e + eBias >= 1) {
      value += rt / c
    } else {
      value += rt * Math.pow(2, 1 - eBias)
    }
    if (value * c >= 2) {
      e++
      c /= 2
    }

    if (e + eBias >= eMax) {
      m = 0
      e = eMax
    } else if (e + eBias >= 1) {
      m = (value * c - 1) * Math.pow(2, mLen)
      e = e + eBias
    } else {
      m = value * Math.pow(2, eBias - 1) * Math.pow(2, mLen)
      e = 0
    }
  }

  for (; mLen >= 8; buffer[offset + i] = m & 0xff, i += d, m /= 256, mLen -= 8) {}

  e = (e << mLen) | m
  eLen += mLen
  for (; eLen > 0; buffer[offset + i] = e & 0xff, i += d, e /= 256, eLen -= 8) {}

  buffer[offset + i - d] |= s * 128
}

},{}],6:[function(require,module,exports){
/*!
 * Determine if an object is a Buffer
 *
 * @author   Feross Aboukhadijeh <feross@feross.org> <http://feross.org>
 * @license  MIT
 */

// The _isBuffer check is for Safari 5-7 support, because it's missing
// Object.prototype.constructor. Remove this eventually
module.exports = function (obj) {
  return obj != null && (isBuffer(obj) || isSlowBuffer(obj) || !!obj._isBuffer)
}

function isBuffer (obj) {
  return !!obj.constructor && typeof obj.constructor.isBuffer === 'function' && obj.constructor.isBuffer(obj)
}

// For Node v0.10 support. Remove this eventually.
function isSlowBuffer (obj) {
  return typeof obj.readFloatLE === 'function' && typeof obj.slice === 'function' && isBuffer(obj.slice(0, 0))
}

},{}],7:[function(require,module,exports){
// shim for using process in browser
var process = module.exports = {};

// cached from whatever global is present so that test runners that stub it
// don't break things.  But we need to wrap it in a try catch in case it is
// wrapped in strict mode code which doesn't define any globals.  It's inside a
// function because try/catches deoptimize in certain engines.

var cachedSetTimeout;
var cachedClearTimeout;

function defaultSetTimout() {
    throw new Error('setTimeout has not been defined');
}
function defaultClearTimeout () {
    throw new Error('clearTimeout has not been defined');
}
(function () {
    try {
        if (typeof setTimeout === 'function') {
            cachedSetTimeout = setTimeout;
        } else {
            cachedSetTimeout = defaultSetTimout;
        }
    } catch (e) {
        cachedSetTimeout = defaultSetTimout;
    }
    try {
        if (typeof clearTimeout === 'function') {
            cachedClearTimeout = clearTimeout;
        } else {
            cachedClearTimeout = defaultClearTimeout;
        }
    } catch (e) {
        cachedClearTimeout = defaultClearTimeout;
    }
} ())
function runTimeout(fun) {
    if (cachedSetTimeout === setTimeout) {
        //normal enviroments in sane situations
        return setTimeout(fun, 0);
    }
    // if setTimeout wasn't available but was latter defined
    if ((cachedSetTimeout === defaultSetTimout || !cachedSetTimeout) && setTimeout) {
        cachedSetTimeout = setTimeout;
        return setTimeout(fun, 0);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedSetTimeout(fun, 0);
    } catch(e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't trust the global object when called normally
            return cachedSetTimeout.call(null, fun, 0);
        } catch(e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error
            return cachedSetTimeout.call(this, fun, 0);
        }
    }


}
function runClearTimeout(marker) {
    if (cachedClearTimeout === clearTimeout) {
        //normal enviroments in sane situations
        return clearTimeout(marker);
    }
    // if clearTimeout wasn't available but was latter defined
    if ((cachedClearTimeout === defaultClearTimeout || !cachedClearTimeout) && clearTimeout) {
        cachedClearTimeout = clearTimeout;
        return clearTimeout(marker);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedClearTimeout(marker);
    } catch (e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't  trust the global object when called normally
            return cachedClearTimeout.call(null, marker);
        } catch (e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error.
            // Some versions of I.E. have different rules for clearTimeout vs setTimeout
            return cachedClearTimeout.call(this, marker);
        }
    }



}
var queue = [];
var draining = false;
var currentQueue;
var queueIndex = -1;

function cleanUpNextTick() {
    if (!draining || !currentQueue) {
        return;
    }
    draining = false;
    if (currentQueue.length) {
        queue = currentQueue.concat(queue);
    } else {
        queueIndex = -1;
    }
    if (queue.length) {
        drainQueue();
    }
}

function drainQueue() {
    if (draining) {
        return;
    }
    var timeout = runTimeout(cleanUpNextTick);
    draining = true;

    var len = queue.length;
    while(len) {
        currentQueue = queue;
        queue = [];
        while (++queueIndex < len) {
            if (currentQueue) {
                currentQueue[queueIndex].run();
            }
        }
        queueIndex = -1;
        len = queue.length;
    }
    currentQueue = null;
    draining = false;
    runClearTimeout(timeout);
}

process.nextTick = function (fun) {
    var args = new Array(arguments.length - 1);
    if (arguments.length > 1) {
        for (var i = 1; i < arguments.length; i++) {
            args[i - 1] = arguments[i];
        }
    }
    queue.push(new Item(fun, args));
    if (queue.length === 1 && !draining) {
        runTimeout(drainQueue);
    }
};

// v8 likes predictible objects
function Item(fun, array) {
    this.fun = fun;
    this.array = array;
}
Item.prototype.run = function () {
    this.fun.apply(null, this.array);
};
process.title = 'browser';
process.browser = true;
process.env = {};
process.argv = [];
process.version = ''; // empty string to avoid regexp issues
process.versions = {};

function noop() {}

process.on = noop;
process.addListener = noop;
process.once = noop;
process.off = noop;
process.removeListener = noop;
process.removeAllListeners = noop;
process.emit = noop;
process.prependListener = noop;
process.prependOnceListener = noop;

process.listeners = function (name) { return [] }

process.binding = function (name) {
    throw new Error('process.binding is not supported');
};

process.cwd = function () { return '/' };
process.chdir = function (dir) {
    throw new Error('process.chdir is not supported');
};
process.umask = function() { return 0; };

},{}],8:[function(require,module,exports){
var getUserMedia = require('getusermedia')

getUserMedia({ video: true, audio: false }, function (err, stream) {
  if (err) return console.error(err)

  var Peer = require('simple-peer')
  var peer = new Peer({
    initiator: location.hash === '#init',
    trickle: false,
    stream: stream
  })

  peer.on('signal', function (data) {
    document.getElementById('yourId').value = JSON.stringify(data)
  })

  document.getElementById('connect').addEventListener('click', function () {
    var otherId = JSON.parse(document.getElementById('otherId').value)
    peer.signal(otherId)
  })

  document.getElementById('send').addEventListener('click', function () {
    var yourMessage = document.getElementById('yourMessage').value
    peer.send(yourMessage)
  })

  peer.on('data', function (data) {
    document.getElementById('messages').textContent += data + '\n'
  })

  peer.on('stream', function (stream) {
    var video = document.getElementById('video')


    video.src = window.URL.createObjectURL(stream)
    video.play()
  })
})
},{"getusermedia":13,"simple-peer":30}],9:[function(require,module,exports){
(function (Buffer){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

// NOTE: These type checking functions intentionally don't use `instanceof`
// because it is fragile and can be easily faked with `Object.create()`.

function isArray(arg) {
  if (Array.isArray) {
    return Array.isArray(arg);
  }
  return objectToString(arg) === '[object Array]';
}
exports.isArray = isArray;

function isBoolean(arg) {
  return typeof arg === 'boolean';
}
exports.isBoolean = isBoolean;

function isNull(arg) {
  return arg === null;
}
exports.isNull = isNull;

function isNullOrUndefined(arg) {
  return arg == null;
}
exports.isNullOrUndefined = isNullOrUndefined;

function isNumber(arg) {
  return typeof arg === 'number';
}
exports.isNumber = isNumber;

function isString(arg) {
  return typeof arg === 'string';
}
exports.isString = isString;

function isSymbol(arg) {
  return typeof arg === 'symbol';
}
exports.isSymbol = isSymbol;

function isUndefined(arg) {
  return arg === void 0;
}
exports.isUndefined = isUndefined;

function isRegExp(re) {
  return objectToString(re) === '[object RegExp]';
}
exports.isRegExp = isRegExp;

function isObject(arg) {
  return typeof arg === 'object' && arg !== null;
}
exports.isObject = isObject;

function isDate(d) {
  return objectToString(d) === '[object Date]';
}
exports.isDate = isDate;

function isError(e) {
  return (objectToString(e) === '[object Error]' || e instanceof Error);
}
exports.isError = isError;

function isFunction(arg) {
  return typeof arg === 'function';
}
exports.isFunction = isFunction;

function isPrimitive(arg) {
  return arg === null ||
         typeof arg === 'boolean' ||
         typeof arg === 'number' ||
         typeof arg === 'string' ||
         typeof arg === 'symbol' ||  // ES6 symbol
         typeof arg === 'undefined';
}
exports.isPrimitive = isPrimitive;

exports.isBuffer = Buffer.isBuffer;

function objectToString(o) {
  return Object.prototype.toString.call(o);
}

}).call(this,{"isBuffer":require("../../../../../../../.nvm/versions/node/v7.7.4/lib/node_modules/browserify/node_modules/is-buffer/index.js")})
},{"../../../../../../../.nvm/versions/node/v7.7.4/lib/node_modules/browserify/node_modules/is-buffer/index.js":6}],10:[function(require,module,exports){
(function (process){
/**
 * This is the web browser implementation of `debug()`.
 *
 * Expose `debug()` as the module.
 */

exports = module.exports = require('./debug');
exports.log = log;
exports.formatArgs = formatArgs;
exports.save = save;
exports.load = load;
exports.useColors = useColors;
exports.storage = 'undefined' != typeof chrome
               && 'undefined' != typeof chrome.storage
                  ? chrome.storage.local
                  : localstorage();

/**
 * Colors.
 */

exports.colors = [
  'lightseagreen',
  'forestgreen',
  'goldenrod',
  'dodgerblue',
  'darkorchid',
  'crimson'
];

/**
 * Currently only WebKit-based Web Inspectors, Firefox >= v31,
 * and the Firebug extension (any Firefox version) are known
 * to support "%c" CSS customizations.
 *
 * TODO: add a `localStorage` variable to explicitly enable/disable colors
 */

function useColors() {
  // NB: In an Electron preload script, document will be defined but not fully
  // initialized. Since we know we're in Chrome, we'll just detect this case
  // explicitly
  if (typeof window !== 'undefined' && window.process && window.process.type === 'renderer') {
    return true;
  }

  // is webkit? http://stackoverflow.com/a/16459606/376773
  // document is undefined in react-native: https://github.com/facebook/react-native/pull/1632
  return (typeof document !== 'undefined' && document.documentElement && document.documentElement.style && document.documentElement.style.WebkitAppearance) ||
    // is firebug? http://stackoverflow.com/a/398120/376773
    (typeof window !== 'undefined' && window.console && (window.console.firebug || (window.console.exception && window.console.table))) ||
    // is firefox >= v31?
    // https://developer.mozilla.org/en-US/docs/Tools/Web_Console#Styling_messages
    (typeof navigator !== 'undefined' && navigator.userAgent && navigator.userAgent.toLowerCase().match(/firefox\/(\d+)/) && parseInt(RegExp.$1, 10) >= 31) ||
    // double check webkit in userAgent just in case we are in a worker
    (typeof navigator !== 'undefined' && navigator.userAgent && navigator.userAgent.toLowerCase().match(/applewebkit\/(\d+)/));
}

/**
 * Map %j to `JSON.stringify()`, since no Web Inspectors do that by default.
 */

exports.formatters.j = function(v) {
  try {
    return JSON.stringify(v);
  } catch (err) {
    return '[UnexpectedJSONParseError]: ' + err.message;
  }
};


/**
 * Colorize log arguments if enabled.
 *
 * @api public
 */

function formatArgs(args) {
  var useColors = this.useColors;

  args[0] = (useColors ? '%c' : '')
    + this.namespace
    + (useColors ? ' %c' : ' ')
    + args[0]
    + (useColors ? '%c ' : ' ')
    + '+' + exports.humanize(this.diff);

  if (!useColors) return;

  var c = 'color: ' + this.color;
  args.splice(1, 0, c, 'color: inherit')

  // the final "%c" is somewhat tricky, because there could be other
  // arguments passed either before or after the %c, so we need to
  // figure out the correct index to insert the CSS into
  var index = 0;
  var lastC = 0;
  args[0].replace(/%[a-zA-Z%]/g, function(match) {
    if ('%%' === match) return;
    index++;
    if ('%c' === match) {
      // we only are interested in the *last* %c
      // (the user may have provided their own)
      lastC = index;
    }
  });

  args.splice(lastC, 0, c);
}

/**
 * Invokes `console.log()` when available.
 * No-op when `console.log` is not a "function".
 *
 * @api public
 */

function log() {
  // this hackery is required for IE8/9, where
  // the `console.log` function doesn't have 'apply'
  return 'object' === typeof console
    && console.log
    && Function.prototype.apply.call(console.log, console, arguments);
}

/**
 * Save `namespaces`.
 *
 * @param {String} namespaces
 * @api private
 */

function save(namespaces) {
  try {
    if (null == namespaces) {
      exports.storage.removeItem('debug');
    } else {
      exports.storage.debug = namespaces;
    }
  } catch(e) {}
}

/**
 * Load `namespaces`.
 *
 * @return {String} returns the previously persisted debug modes
 * @api private
 */

function load() {
  var r;
  try {
    r = exports.storage.debug;
  } catch(e) {}

  // If debug isn't set in LS, and we're in Electron, try to load $DEBUG
  if (!r && typeof process !== 'undefined' && 'env' in process) {
    r = process.env.DEBUG;
  }

  return r;
}

/**
 * Enable namespaces listed in `localStorage.debug` initially.
 */

exports.enable(load());

/**
 * Localstorage attempts to return the localstorage.
 *
 * This is necessary because safari throws
 * when a user disables cookies/localstorage
 * and you attempt to access it.
 *
 * @return {LocalStorage}
 * @api private
 */

function localstorage() {
  try {
    return window.localStorage;
  } catch (e) {}
}

}).call(this,require('_process'))
},{"./debug":11,"_process":7}],11:[function(require,module,exports){

/**
 * This is the common logic for both the Node.js and web browser
 * implementations of `debug()`.
 *
 * Expose `debug()` as the module.
 */

exports = module.exports = createDebug.debug = createDebug['default'] = createDebug;
exports.coerce = coerce;
exports.disable = disable;
exports.enable = enable;
exports.enabled = enabled;
exports.humanize = require('ms');

/**
 * The currently active debug mode names, and names to skip.
 */

exports.names = [];
exports.skips = [];

/**
 * Map of special "%n" handling functions, for the debug "format" argument.
 *
 * Valid key names are a single, lower or upper-case letter, i.e. "n" and "N".
 */

exports.formatters = {};

/**
 * Previous log timestamp.
 */

var prevTime;

/**
 * Select a color.
 * @param {String} namespace
 * @return {Number}
 * @api private
 */

function selectColor(namespace) {
  var hash = 0, i;

  for (i in namespace) {
    hash  = ((hash << 5) - hash) + namespace.charCodeAt(i);
    hash |= 0; // Convert to 32bit integer
  }

  return exports.colors[Math.abs(hash) % exports.colors.length];
}

/**
 * Create a debugger with the given `namespace`.
 *
 * @param {String} namespace
 * @return {Function}
 * @api public
 */

function createDebug(namespace) {

  function debug() {
    // disabled?
    if (!debug.enabled) return;

    var self = debug;

    // set `diff` timestamp
    var curr = +new Date();
    var ms = curr - (prevTime || curr);
    self.diff = ms;
    self.prev = prevTime;
    self.curr = curr;
    prevTime = curr;

    // turn the `arguments` into a proper Array
    var args = new Array(arguments.length);
    for (var i = 0; i < args.length; i++) {
      args[i] = arguments[i];
    }

    args[0] = exports.coerce(args[0]);

    if ('string' !== typeof args[0]) {
      // anything else let's inspect with %O
      args.unshift('%O');
    }

    // apply any `formatters` transformations
    var index = 0;
    args[0] = args[0].replace(/%([a-zA-Z%])/g, function(match, format) {
      // if we encounter an escaped % then don't increase the array index
      if (match === '%%') return match;
      index++;
      var formatter = exports.formatters[format];
      if ('function' === typeof formatter) {
        var val = args[index];
        match = formatter.call(self, val);

        // now we need to remove `args[index]` since it's inlined in the `format`
        args.splice(index, 1);
        index--;
      }
      return match;
    });

    // apply env-specific formatting (colors, etc.)
    exports.formatArgs.call(self, args);

    var logFn = debug.log || exports.log || console.log.bind(console);
    logFn.apply(self, args);
  }

  debug.namespace = namespace;
  debug.enabled = exports.enabled(namespace);
  debug.useColors = exports.useColors();
  debug.color = selectColor(namespace);

  // env-specific initialization logic for debug instances
  if ('function' === typeof exports.init) {
    exports.init(debug);
  }

  return debug;
}

/**
 * Enables a debug mode by namespaces. This can include modes
 * separated by a colon and wildcards.
 *
 * @param {String} namespaces
 * @api public
 */

function enable(namespaces) {
  exports.save(namespaces);

  exports.names = [];
  exports.skips = [];

  var split = (typeof namespaces === 'string' ? namespaces : '').split(/[\s,]+/);
  var len = split.length;

  for (var i = 0; i < len; i++) {
    if (!split[i]) continue; // ignore empty strings
    namespaces = split[i].replace(/\*/g, '.*?');
    if (namespaces[0] === '-') {
      exports.skips.push(new RegExp('^' + namespaces.substr(1) + '$'));
    } else {
      exports.names.push(new RegExp('^' + namespaces + '$'));
    }
  }
}

/**
 * Disable debug output.
 *
 * @api public
 */

function disable() {
  exports.enable('');
}

/**
 * Returns true if the given mode name is enabled, false otherwise.
 *
 * @param {String} name
 * @return {Boolean}
 * @api public
 */

function enabled(name) {
  var i, len;
  for (i = 0, len = exports.skips.length; i < len; i++) {
    if (exports.skips[i].test(name)) {
      return false;
    }
  }
  for (i = 0, len = exports.names.length; i < len; i++) {
    if (exports.names[i].test(name)) {
      return true;
    }
  }
  return false;
}

/**
 * Coerce `val`.
 *
 * @param {Mixed} val
 * @return {Mixed}
 * @api private
 */

function coerce(val) {
  if (val instanceof Error) return val.stack || val.message;
  return val;
}

},{"ms":16}],12:[function(require,module,exports){
// originally pulled out of simple-peer

module.exports = function getBrowserRTC () {
  if (typeof window === 'undefined') return null
  var wrtc = {
    RTCPeerConnection: window.RTCPeerConnection || window.mozRTCPeerConnection ||
      window.webkitRTCPeerConnection,
    RTCSessionDescription: window.RTCSessionDescription ||
      window.mozRTCSessionDescription || window.webkitRTCSessionDescription,
    RTCIceCandidate: window.RTCIceCandidate || window.mozRTCIceCandidate ||
      window.webkitRTCIceCandidate
  }
  if (!wrtc.RTCPeerConnection) return null
  return wrtc
}

},{}],13:[function(require,module,exports){
// getUserMedia helper by @HenrikJoreteg used for navigator.getUserMedia shim
var adapter = require('webrtc-adapter');

module.exports = function (constraints, cb) {
    var error;
    var haveOpts = arguments.length === 2;
    var defaultOpts = {video: true, audio: true};

    var denied = 'PermissionDeniedError';
    var altDenied = 'PERMISSION_DENIED';
    var notSatisfied = 'ConstraintNotSatisfiedError';

    // make constraints optional
    if (!haveOpts) {
        cb = constraints;
        constraints = defaultOpts;
    }

    // treat lack of browser support like an error
    if (typeof navigator === 'undefined' || !navigator.getUserMedia) {
        // throw proper error per spec
        error = new Error('MediaStreamError');
        error.name = 'NotSupportedError';

        // keep all callbacks async
        return setTimeout(function () {
            cb(error);
        }, 0);
    }

    // normalize error handling when no media types are requested
    if (!constraints.audio && !constraints.video) {
        error = new Error('MediaStreamError');
        error.name = 'NoMediaRequestedError';

        // keep all callbacks async
        return setTimeout(function () {
            cb(error);
        }, 0);
    }

    navigator.mediaDevices.getUserMedia(constraints)
    .then(function (stream) {
        cb(null, stream);
    }).catch(function (err) {
        var error;
        // coerce into an error object since FF gives us a string
        // there are only two valid names according to the spec
        // we coerce all non-denied to "constraint not satisfied".
        if (typeof err === 'string') {
            error = new Error('MediaStreamError');
            if (err === denied || err === altDenied) {
                error.name = denied;
            } else {
                error.name = notSatisfied;
            }
        } else {
            // if we get an error object make sure '.name' property is set
            // according to spec: http://dev.w3.org/2011/webrtc/editor/getusermedia.html#navigatorusermediaerror-and-navigatorusermediaerrorcallback
            error = err;
            if (!error.name) {
                // this is likely chrome which
                // sets a property called "ERROR_DENIED" on the error object
                // if so we make sure to set a name
                if (error[denied]) {
                    err.name = denied;
                } else {
                    err.name = notSatisfied;
                }
            }
        }

        cb(error);
    });
};

},{"webrtc-adapter":34}],14:[function(require,module,exports){
if (typeof Object.create === 'function') {
  // implementation from standard node.js 'util' module
  module.exports = function inherits(ctor, superCtor) {
    ctor.super_ = superCtor
    ctor.prototype = Object.create(superCtor.prototype, {
      constructor: {
        value: ctor,
        enumerable: false,
        writable: true,
        configurable: true
      }
    });
  };
} else {
  // old school shim for old browsers
  module.exports = function inherits(ctor, superCtor) {
    ctor.super_ = superCtor
    var TempCtor = function () {}
    TempCtor.prototype = superCtor.prototype
    ctor.prototype = new TempCtor()
    ctor.prototype.constructor = ctor
  }
}

},{}],15:[function(require,module,exports){
var toString = {}.toString;

module.exports = Array.isArray || function (arr) {
  return toString.call(arr) == '[object Array]';
};

},{}],16:[function(require,module,exports){
/**
 * Helpers.
 */

var s = 1000;
var m = s * 60;
var h = m * 60;
var d = h * 24;
var y = d * 365.25;

/**
 * Parse or format the given `val`.
 *
 * Options:
 *
 *  - `long` verbose formatting [false]
 *
 * @param {String|Number} val
 * @param {Object} [options]
 * @throws {Error} throw an error if val is not a non-empty string or a number
 * @return {String|Number}
 * @api public
 */

module.exports = function(val, options) {
  options = options || {};
  var type = typeof val;
  if (type === 'string' && val.length > 0) {
    return parse(val);
  } else if (type === 'number' && isNaN(val) === false) {
    return options.long ? fmtLong(val) : fmtShort(val);
  }
  throw new Error(
    'val is not a non-empty string or a valid number. val=' +
      JSON.stringify(val)
  );
};

/**
 * Parse the given `str` and return milliseconds.
 *
 * @param {String} str
 * @return {Number}
 * @api private
 */

function parse(str) {
  str = String(str);
  if (str.length > 100) {
    return;
  }
  var match = /^((?:\d+)?\.?\d+) *(milliseconds?|msecs?|ms|seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|years?|yrs?|y)?$/i.exec(
    str
  );
  if (!match) {
    return;
  }
  var n = parseFloat(match[1]);
  var type = (match[2] || 'ms').toLowerCase();
  switch (type) {
    case 'years':
    case 'year':
    case 'yrs':
    case 'yr':
    case 'y':
      return n * y;
    case 'days':
    case 'day':
    case 'd':
      return n * d;
    case 'hours':
    case 'hour':
    case 'hrs':
    case 'hr':
    case 'h':
      return n * h;
    case 'minutes':
    case 'minute':
    case 'mins':
    case 'min':
    case 'm':
      return n * m;
    case 'seconds':
    case 'second':
    case 'secs':
    case 'sec':
    case 's':
      return n * s;
    case 'milliseconds':
    case 'millisecond':
    case 'msecs':
    case 'msec':
    case 'ms':
      return n;
    default:
      return undefined;
  }
}

/**
 * Short format for `ms`.
 *
 * @param {Number} ms
 * @return {String}
 * @api private
 */

function fmtShort(ms) {
  if (ms >= d) {
    return Math.round(ms / d) + 'd';
  }
  if (ms >= h) {
    return Math.round(ms / h) + 'h';
  }
  if (ms >= m) {
    return Math.round(ms / m) + 'm';
  }
  if (ms >= s) {
    return Math.round(ms / s) + 's';
  }
  return ms + 'ms';
}

/**
 * Long format for `ms`.
 *
 * @param {Number} ms
 * @return {String}
 * @api private
 */

function fmtLong(ms) {
  return plural(ms, d, 'day') ||
    plural(ms, h, 'hour') ||
    plural(ms, m, 'minute') ||
    plural(ms, s, 'second') ||
    ms + ' ms';
}

/**
 * Pluralization helper.
 */

function plural(ms, n, name) {
  if (ms < n) {
    return;
  }
  if (ms < n * 1.5) {
    return Math.floor(ms / n) + ' ' + name;
  }
  return Math.ceil(ms / n) + ' ' + name + 's';
}

},{}],17:[function(require,module,exports){
(function (process){
'use strict';

if (!process.version ||
    process.version.indexOf('v0.') === 0 ||
    process.version.indexOf('v1.') === 0 && process.version.indexOf('v1.8.') !== 0) {
  module.exports = nextTick;
} else {
  module.exports = process.nextTick;
}

function nextTick(fn, arg1, arg2, arg3) {
  if (typeof fn !== 'function') {
    throw new TypeError('"callback" argument must be a function');
  }
  var len = arguments.length;
  var args, i;
  switch (len) {
  case 0:
  case 1:
    return process.nextTick(fn);
  case 2:
    return process.nextTick(function afterTickOne() {
      fn.call(null, arg1);
    });
  case 3:
    return process.nextTick(function afterTickTwo() {
      fn.call(null, arg1, arg2);
    });
  case 4:
    return process.nextTick(function afterTickThree() {
      fn.call(null, arg1, arg2, arg3);
    });
  default:
    args = new Array(len - 1);
    i = 0;
    while (i < args.length) {
      args[i++] = arguments[i];
    }
    return process.nextTick(function afterTick() {
      fn.apply(null, args);
    });
  }
}

}).call(this,require('_process'))
},{"_process":7}],18:[function(require,module,exports){
(function (process,global){
'use strict'

function oldBrowser () {
  throw new Error('secure random number generation not supported by this browser\nuse chrome, FireFox or Internet Explorer 11')
}

var Buffer = require('safe-buffer').Buffer
var crypto = global.crypto || global.msCrypto

if (crypto && crypto.getRandomValues) {
  module.exports = randomBytes
} else {
  module.exports = oldBrowser
}

function randomBytes (size, cb) {
  // phantomjs needs to throw
  if (size > 65536) throw new Error('requested too many random bytes')
  // in case browserify  isn't using the Uint8Array version
  var rawBytes = new global.Uint8Array(size)

  // This will not work in older browsers.
  // See https://developer.mozilla.org/en-US/docs/Web/API/window.crypto.getRandomValues
  if (size > 0) {  // getRandomValues fails on IE if size == 0
    crypto.getRandomValues(rawBytes)
  }

  // XXX: phantomjs doesn't like a buffer being passed here
  var bytes = Buffer.from(rawBytes.buffer)

  if (typeof cb === 'function') {
    return process.nextTick(function () {
      cb(null, bytes)
    })
  }

  return bytes
}

}).call(this,require('_process'),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"_process":7,"safe-buffer":28}],19:[function(require,module,exports){
// a duplex stream is just a stream that is both readable and writable.
// Since JS doesn't have multiple prototypal inheritance, this class
// prototypally inherits from Readable, and then parasitically from
// Writable.

'use strict';

/*<replacement>*/

var objectKeys = Object.keys || function (obj) {
  var keys = [];
  for (var key in obj) {
    keys.push(key);
  }return keys;
};
/*</replacement>*/

module.exports = Duplex;

/*<replacement>*/
var processNextTick = require('process-nextick-args');
/*</replacement>*/

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

var Readable = require('./_stream_readable');
var Writable = require('./_stream_writable');

util.inherits(Duplex, Readable);

var keys = objectKeys(Writable.prototype);
for (var v = 0; v < keys.length; v++) {
  var method = keys[v];
  if (!Duplex.prototype[method]) Duplex.prototype[method] = Writable.prototype[method];
}

function Duplex(options) {
  if (!(this instanceof Duplex)) return new Duplex(options);

  Readable.call(this, options);
  Writable.call(this, options);

  if (options && options.readable === false) this.readable = false;

  if (options && options.writable === false) this.writable = false;

  this.allowHalfOpen = true;
  if (options && options.allowHalfOpen === false) this.allowHalfOpen = false;

  this.once('end', onend);
}

// the no-half-open enforcer
function onend() {
  // if we allow half-open state, or if the writable side ended,
  // then we're ok.
  if (this.allowHalfOpen || this._writableState.ended) return;

  // no more data can be written.
  // But allow more writes to happen in this tick.
  processNextTick(onEndNT, this);
}

function onEndNT(self) {
  self.end();
}

function forEach(xs, f) {
  for (var i = 0, l = xs.length; i < l; i++) {
    f(xs[i], i);
  }
}
},{"./_stream_readable":21,"./_stream_writable":23,"core-util-is":9,"inherits":14,"process-nextick-args":17}],20:[function(require,module,exports){
// a passthrough stream.
// basically just the most minimal sort of Transform stream.
// Every written chunk gets output as-is.

'use strict';

module.exports = PassThrough;

var Transform = require('./_stream_transform');

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

util.inherits(PassThrough, Transform);

function PassThrough(options) {
  if (!(this instanceof PassThrough)) return new PassThrough(options);

  Transform.call(this, options);
}

PassThrough.prototype._transform = function (chunk, encoding, cb) {
  cb(null, chunk);
};
},{"./_stream_transform":22,"core-util-is":9,"inherits":14}],21:[function(require,module,exports){
(function (process){
'use strict';

module.exports = Readable;

/*<replacement>*/
var processNextTick = require('process-nextick-args');
/*</replacement>*/

/*<replacement>*/
var isArray = require('isarray');
/*</replacement>*/

/*<replacement>*/
var Duplex;
/*</replacement>*/

Readable.ReadableState = ReadableState;

/*<replacement>*/
var EE = require('events').EventEmitter;

var EElistenerCount = function (emitter, type) {
  return emitter.listeners(type).length;
};
/*</replacement>*/

/*<replacement>*/
var Stream = require('./internal/streams/stream');
/*</replacement>*/

/*<replacement>*/
var Buffer = require('safe-buffer').Buffer;
/*</replacement>*/

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

/*<replacement>*/
var debugUtil = require('util');
var debug = void 0;
if (debugUtil && debugUtil.debuglog) {
  debug = debugUtil.debuglog('stream');
} else {
  debug = function () {};
}
/*</replacement>*/

var BufferList = require('./internal/streams/BufferList');
var StringDecoder;

util.inherits(Readable, Stream);

var kProxyEvents = ['error', 'close', 'destroy', 'pause', 'resume'];

function prependListener(emitter, event, fn) {
  // Sadly this is not cacheable as some libraries bundle their own
  // event emitter implementation with them.
  if (typeof emitter.prependListener === 'function') {
    return emitter.prependListener(event, fn);
  } else {
    // This is a hack to make sure that our error handler is attached before any
    // userland ones.  NEVER DO THIS. This is here only because this code needs
    // to continue to work with older versions of Node.js that do not include
    // the prependListener() method. The goal is to eventually remove this hack.
    if (!emitter._events || !emitter._events[event]) emitter.on(event, fn);else if (isArray(emitter._events[event])) emitter._events[event].unshift(fn);else emitter._events[event] = [fn, emitter._events[event]];
  }
}

function ReadableState(options, stream) {
  Duplex = Duplex || require('./_stream_duplex');

  options = options || {};

  // object stream flag. Used to make read(n) ignore n and to
  // make all the buffer merging and length checks go away
  this.objectMode = !!options.objectMode;

  if (stream instanceof Duplex) this.objectMode = this.objectMode || !!options.readableObjectMode;

  // the point at which it stops calling _read() to fill the buffer
  // Note: 0 is a valid value, means "don't call _read preemptively ever"
  var hwm = options.highWaterMark;
  var defaultHwm = this.objectMode ? 16 : 16 * 1024;
  this.highWaterMark = hwm || hwm === 0 ? hwm : defaultHwm;

  // cast to ints.
  this.highWaterMark = ~~this.highWaterMark;

  // A linked list is used to store data chunks instead of an array because the
  // linked list can remove elements from the beginning faster than
  // array.shift()
  this.buffer = new BufferList();
  this.length = 0;
  this.pipes = null;
  this.pipesCount = 0;
  this.flowing = null;
  this.ended = false;
  this.endEmitted = false;
  this.reading = false;

  // a flag to be able to tell if the onwrite cb is called immediately,
  // or on a later tick.  We set this to true at first, because any
  // actions that shouldn't happen until "later" should generally also
  // not happen before the first write call.
  this.sync = true;

  // whenever we return null, then we set a flag to say
  // that we're awaiting a 'readable' event emission.
  this.needReadable = false;
  this.emittedReadable = false;
  this.readableListening = false;
  this.resumeScheduled = false;

  // Crypto is kind of old and crusty.  Historically, its default string
  // encoding is 'binary' so we have to make this configurable.
  // Everything else in the universe uses 'utf8', though.
  this.defaultEncoding = options.defaultEncoding || 'utf8';

  // when piping, we only care about 'readable' events that happen
  // after read()ing all the bytes and not getting any pushback.
  this.ranOut = false;

  // the number of writers that are awaiting a drain event in .pipe()s
  this.awaitDrain = 0;

  // if true, a maybeReadMore has been scheduled
  this.readingMore = false;

  this.decoder = null;
  this.encoding = null;
  if (options.encoding) {
    if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder;
    this.decoder = new StringDecoder(options.encoding);
    this.encoding = options.encoding;
  }
}

function Readable(options) {
  Duplex = Duplex || require('./_stream_duplex');

  if (!(this instanceof Readable)) return new Readable(options);

  this._readableState = new ReadableState(options, this);

  // legacy
  this.readable = true;

  if (options && typeof options.read === 'function') this._read = options.read;

  Stream.call(this);
}

// Manually shove something into the read() buffer.
// This returns true if the highWaterMark has not been hit yet,
// similar to how Writable.write() returns true if you should
// write() some more.
Readable.prototype.push = function (chunk, encoding) {
  var state = this._readableState;

  if (!state.objectMode && typeof chunk === 'string') {
    encoding = encoding || state.defaultEncoding;
    if (encoding !== state.encoding) {
      chunk = Buffer.from(chunk, encoding);
      encoding = '';
    }
  }

  return readableAddChunk(this, state, chunk, encoding, false);
};

// Unshift should *always* be something directly out of read()
Readable.prototype.unshift = function (chunk) {
  var state = this._readableState;
  return readableAddChunk(this, state, chunk, '', true);
};

Readable.prototype.isPaused = function () {
  return this._readableState.flowing === false;
};

function readableAddChunk(stream, state, chunk, encoding, addToFront) {
  var er = chunkInvalid(state, chunk);
  if (er) {
    stream.emit('error', er);
  } else if (chunk === null) {
    state.reading = false;
    onEofChunk(stream, state);
  } else if (state.objectMode || chunk && chunk.length > 0) {
    if (state.ended && !addToFront) {
      var e = new Error('stream.push() after EOF');
      stream.emit('error', e);
    } else if (state.endEmitted && addToFront) {
      var _e = new Error('stream.unshift() after end event');
      stream.emit('error', _e);
    } else {
      var skipAdd;
      if (state.decoder && !addToFront && !encoding) {
        chunk = state.decoder.write(chunk);
        skipAdd = !state.objectMode && chunk.length === 0;
      }

      if (!addToFront) state.reading = false;

      // Don't add to the buffer if we've decoded to an empty string chunk and
      // we're not in object mode
      if (!skipAdd) {
        // if we want the data now, just emit it.
        if (state.flowing && state.length === 0 && !state.sync) {
          stream.emit('data', chunk);
          stream.read(0);
        } else {
          // update the buffer info.
          state.length += state.objectMode ? 1 : chunk.length;
          if (addToFront) state.buffer.unshift(chunk);else state.buffer.push(chunk);

          if (state.needReadable) emitReadable(stream);
        }
      }

      maybeReadMore(stream, state);
    }
  } else if (!addToFront) {
    state.reading = false;
  }

  return needMoreData(state);
}

// if it's past the high water mark, we can push in some more.
// Also, if we have no data yet, we can stand some
// more bytes.  This is to work around cases where hwm=0,
// such as the repl.  Also, if the push() triggered a
// readable event, and the user called read(largeNumber) such that
// needReadable was set, then we ought to push more, so that another
// 'readable' event will be triggered.
function needMoreData(state) {
  return !state.ended && (state.needReadable || state.length < state.highWaterMark || state.length === 0);
}

// backwards compatibility.
Readable.prototype.setEncoding = function (enc) {
  if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder;
  this._readableState.decoder = new StringDecoder(enc);
  this._readableState.encoding = enc;
  return this;
};

// Don't raise the hwm > 8MB
var MAX_HWM = 0x800000;
function computeNewHighWaterMark(n) {
  if (n >= MAX_HWM) {
    n = MAX_HWM;
  } else {
    // Get the next highest power of 2 to prevent increasing hwm excessively in
    // tiny amounts
    n--;
    n |= n >>> 1;
    n |= n >>> 2;
    n |= n >>> 4;
    n |= n >>> 8;
    n |= n >>> 16;
    n++;
  }
  return n;
}

// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function howMuchToRead(n, state) {
  if (n <= 0 || state.length === 0 && state.ended) return 0;
  if (state.objectMode) return 1;
  if (n !== n) {
    // Only flow one buffer at a time
    if (state.flowing && state.length) return state.buffer.head.data.length;else return state.length;
  }
  // If we're asking for more than the current hwm, then raise the hwm.
  if (n > state.highWaterMark) state.highWaterMark = computeNewHighWaterMark(n);
  if (n <= state.length) return n;
  // Don't have enough
  if (!state.ended) {
    state.needReadable = true;
    return 0;
  }
  return state.length;
}

// you can override either this method, or the async _read(n) below.
Readable.prototype.read = function (n) {
  debug('read', n);
  n = parseInt(n, 10);
  var state = this._readableState;
  var nOrig = n;

  if (n !== 0) state.emittedReadable = false;

  // if we're doing read(0) to trigger a readable event, but we
  // already have a bunch of data in the buffer, then just trigger
  // the 'readable' event and move on.
  if (n === 0 && state.needReadable && (state.length >= state.highWaterMark || state.ended)) {
    debug('read: emitReadable', state.length, state.ended);
    if (state.length === 0 && state.ended) endReadable(this);else emitReadable(this);
    return null;
  }

  n = howMuchToRead(n, state);

  // if we've ended, and we're now clear, then finish it up.
  if (n === 0 && state.ended) {
    if (state.length === 0) endReadable(this);
    return null;
  }

  // All the actual chunk generation logic needs to be
  // *below* the call to _read.  The reason is that in certain
  // synthetic stream cases, such as passthrough streams, _read
  // may be a completely synchronous operation which may change
  // the state of the read buffer, providing enough data when
  // before there was *not* enough.
  //
  // So, the steps are:
  // 1. Figure out what the state of things will be after we do
  // a read from the buffer.
  //
  // 2. If that resulting state will trigger a _read, then call _read.
  // Note that this may be asynchronous, or synchronous.  Yes, it is
  // deeply ugly to write APIs this way, but that still doesn't mean
  // that the Readable class should behave improperly, as streams are
  // designed to be sync/async agnostic.
  // Take note if the _read call is sync or async (ie, if the read call
  // has returned yet), so that we know whether or not it's safe to emit
  // 'readable' etc.
  //
  // 3. Actually pull the requested chunks out of the buffer and return.

  // if we need a readable event, then we need to do some reading.
  var doRead = state.needReadable;
  debug('need readable', doRead);

  // if we currently have less than the highWaterMark, then also read some
  if (state.length === 0 || state.length - n < state.highWaterMark) {
    doRead = true;
    debug('length less than watermark', doRead);
  }

  // however, if we've ended, then there's no point, and if we're already
  // reading, then it's unnecessary.
  if (state.ended || state.reading) {
    doRead = false;
    debug('reading or ended', doRead);
  } else if (doRead) {
    debug('do read');
    state.reading = true;
    state.sync = true;
    // if the length is currently zero, then we *need* a readable event.
    if (state.length === 0) state.needReadable = true;
    // call internal read method
    this._read(state.highWaterMark);
    state.sync = false;
    // If _read pushed data synchronously, then `reading` will be false,
    // and we need to re-evaluate how much data we can return to the user.
    if (!state.reading) n = howMuchToRead(nOrig, state);
  }

  var ret;
  if (n > 0) ret = fromList(n, state);else ret = null;

  if (ret === null) {
    state.needReadable = true;
    n = 0;
  } else {
    state.length -= n;
  }

  if (state.length === 0) {
    // If we have nothing in the buffer, then we want to know
    // as soon as we *do* get something into the buffer.
    if (!state.ended) state.needReadable = true;

    // If we tried to read() past the EOF, then emit end on the next tick.
    if (nOrig !== n && state.ended) endReadable(this);
  }

  if (ret !== null) this.emit('data', ret);

  return ret;
};

function chunkInvalid(state, chunk) {
  var er = null;
  if (!Buffer.isBuffer(chunk) && typeof chunk !== 'string' && chunk !== null && chunk !== undefined && !state.objectMode) {
    er = new TypeError('Invalid non-string/buffer chunk');
  }
  return er;
}

function onEofChunk(stream, state) {
  if (state.ended) return;
  if (state.decoder) {
    var chunk = state.decoder.end();
    if (chunk && chunk.length) {
      state.buffer.push(chunk);
      state.length += state.objectMode ? 1 : chunk.length;
    }
  }
  state.ended = true;

  // emit 'readable' now to make sure it gets picked up.
  emitReadable(stream);
}

// Don't emit readable right away in sync mode, because this can trigger
// another read() call => stack overflow.  This way, it might trigger
// a nextTick recursion warning, but that's not so bad.
function emitReadable(stream) {
  var state = stream._readableState;
  state.needReadable = false;
  if (!state.emittedReadable) {
    debug('emitReadable', state.flowing);
    state.emittedReadable = true;
    if (state.sync) processNextTick(emitReadable_, stream);else emitReadable_(stream);
  }
}

function emitReadable_(stream) {
  debug('emit readable');
  stream.emit('readable');
  flow(stream);
}

// at this point, the user has presumably seen the 'readable' event,
// and called read() to consume some data.  that may have triggered
// in turn another _read(n) call, in which case reading = true if
// it's in progress.
// However, if we're not ended, or reading, and the length < hwm,
// then go ahead and try to read some more preemptively.
function maybeReadMore(stream, state) {
  if (!state.readingMore) {
    state.readingMore = true;
    processNextTick(maybeReadMore_, stream, state);
  }
}

function maybeReadMore_(stream, state) {
  var len = state.length;
  while (!state.reading && !state.flowing && !state.ended && state.length < state.highWaterMark) {
    debug('maybeReadMore read 0');
    stream.read(0);
    if (len === state.length)
      // didn't get any data, stop spinning.
      break;else len = state.length;
  }
  state.readingMore = false;
}

// abstract method.  to be overridden in specific implementation classes.
// call cb(er, data) where data is <= n in length.
// for virtual (non-string, non-buffer) streams, "length" is somewhat
// arbitrary, and perhaps not very meaningful.
Readable.prototype._read = function (n) {
  this.emit('error', new Error('_read() is not implemented'));
};

Readable.prototype.pipe = function (dest, pipeOpts) {
  var src = this;
  var state = this._readableState;

  switch (state.pipesCount) {
    case 0:
      state.pipes = dest;
      break;
    case 1:
      state.pipes = [state.pipes, dest];
      break;
    default:
      state.pipes.push(dest);
      break;
  }
  state.pipesCount += 1;
  debug('pipe count=%d opts=%j', state.pipesCount, pipeOpts);

  var doEnd = (!pipeOpts || pipeOpts.end !== false) && dest !== process.stdout && dest !== process.stderr;

  var endFn = doEnd ? onend : unpipe;
  if (state.endEmitted) processNextTick(endFn);else src.once('end', endFn);

  dest.on('unpipe', onunpipe);
  function onunpipe(readable) {
    debug('onunpipe');
    if (readable === src) {
      cleanup();
    }
  }

  function onend() {
    debug('onend');
    dest.end();
  }

  // when the dest drains, it reduces the awaitDrain counter
  // on the source.  This would be more elegant with a .once()
  // handler in flow(), but adding and removing repeatedly is
  // too slow.
  var ondrain = pipeOnDrain(src);
  dest.on('drain', ondrain);

  var cleanedUp = false;
  function cleanup() {
    debug('cleanup');
    // cleanup event handlers once the pipe is broken
    dest.removeListener('close', onclose);
    dest.removeListener('finish', onfinish);
    dest.removeListener('drain', ondrain);
    dest.removeListener('error', onerror);
    dest.removeListener('unpipe', onunpipe);
    src.removeListener('end', onend);
    src.removeListener('end', unpipe);
    src.removeListener('data', ondata);

    cleanedUp = true;

    // if the reader is waiting for a drain event from this
    // specific writer, then it would cause it to never start
    // flowing again.
    // So, if this is awaiting a drain, then we just call it now.
    // If we don't know, then assume that we are waiting for one.
    if (state.awaitDrain && (!dest._writableState || dest._writableState.needDrain)) ondrain();
  }

  // If the user pushes more data while we're writing to dest then we'll end up
  // in ondata again. However, we only want to increase awaitDrain once because
  // dest will only emit one 'drain' event for the multiple writes.
  // => Introduce a guard on increasing awaitDrain.
  var increasedAwaitDrain = false;
  src.on('data', ondata);
  function ondata(chunk) {
    debug('ondata');
    increasedAwaitDrain = false;
    var ret = dest.write(chunk);
    if (false === ret && !increasedAwaitDrain) {
      // If the user unpiped during `dest.write()`, it is possible
      // to get stuck in a permanently paused state if that write
      // also returned false.
      // => Check whether `dest` is still a piping destination.
      if ((state.pipesCount === 1 && state.pipes === dest || state.pipesCount > 1 && indexOf(state.pipes, dest) !== -1) && !cleanedUp) {
        debug('false write response, pause', src._readableState.awaitDrain);
        src._readableState.awaitDrain++;
        increasedAwaitDrain = true;
      }
      src.pause();
    }
  }

  // if the dest has an error, then stop piping into it.
  // however, don't suppress the throwing behavior for this.
  function onerror(er) {
    debug('onerror', er);
    unpipe();
    dest.removeListener('error', onerror);
    if (EElistenerCount(dest, 'error') === 0) dest.emit('error', er);
  }

  // Make sure our error handler is attached before userland ones.
  prependListener(dest, 'error', onerror);

  // Both close and finish should trigger unpipe, but only once.
  function onclose() {
    dest.removeListener('finish', onfinish);
    unpipe();
  }
  dest.once('close', onclose);
  function onfinish() {
    debug('onfinish');
    dest.removeListener('close', onclose);
    unpipe();
  }
  dest.once('finish', onfinish);

  function unpipe() {
    debug('unpipe');
    src.unpipe(dest);
  }

  // tell the dest that it's being piped to
  dest.emit('pipe', src);

  // start the flow if it hasn't been started already.
  if (!state.flowing) {
    debug('pipe resume');
    src.resume();
  }

  return dest;
};

function pipeOnDrain(src) {
  return function () {
    var state = src._readableState;
    debug('pipeOnDrain', state.awaitDrain);
    if (state.awaitDrain) state.awaitDrain--;
    if (state.awaitDrain === 0 && EElistenerCount(src, 'data')) {
      state.flowing = true;
      flow(src);
    }
  };
}

Readable.prototype.unpipe = function (dest) {
  var state = this._readableState;

  // if we're not piping anywhere, then do nothing.
  if (state.pipesCount === 0) return this;

  // just one destination.  most common case.
  if (state.pipesCount === 1) {
    // passed in one, but it's not the right one.
    if (dest && dest !== state.pipes) return this;

    if (!dest) dest = state.pipes;

    // got a match.
    state.pipes = null;
    state.pipesCount = 0;
    state.flowing = false;
    if (dest) dest.emit('unpipe', this);
    return this;
  }

  // slow case. multiple pipe destinations.

  if (!dest) {
    // remove all.
    var dests = state.pipes;
    var len = state.pipesCount;
    state.pipes = null;
    state.pipesCount = 0;
    state.flowing = false;

    for (var i = 0; i < len; i++) {
      dests[i].emit('unpipe', this);
    }return this;
  }

  // try to find the right one.
  var index = indexOf(state.pipes, dest);
  if (index === -1) return this;

  state.pipes.splice(index, 1);
  state.pipesCount -= 1;
  if (state.pipesCount === 1) state.pipes = state.pipes[0];

  dest.emit('unpipe', this);

  return this;
};

// set up data events if they are asked for
// Ensure readable listeners eventually get something
Readable.prototype.on = function (ev, fn) {
  var res = Stream.prototype.on.call(this, ev, fn);

  if (ev === 'data') {
    // Start flowing on next tick if stream isn't explicitly paused
    if (this._readableState.flowing !== false) this.resume();
  } else if (ev === 'readable') {
    var state = this._readableState;
    if (!state.endEmitted && !state.readableListening) {
      state.readableListening = state.needReadable = true;
      state.emittedReadable = false;
      if (!state.reading) {
        processNextTick(nReadingNextTick, this);
      } else if (state.length) {
        emitReadable(this, state);
      }
    }
  }

  return res;
};
Readable.prototype.addListener = Readable.prototype.on;

function nReadingNextTick(self) {
  debug('readable nexttick read 0');
  self.read(0);
}

// pause() and resume() are remnants of the legacy readable stream API
// If the user uses them, then switch into old mode.
Readable.prototype.resume = function () {
  var state = this._readableState;
  if (!state.flowing) {
    debug('resume');
    state.flowing = true;
    resume(this, state);
  }
  return this;
};

function resume(stream, state) {
  if (!state.resumeScheduled) {
    state.resumeScheduled = true;
    processNextTick(resume_, stream, state);
  }
}

function resume_(stream, state) {
  if (!state.reading) {
    debug('resume read 0');
    stream.read(0);
  }

  state.resumeScheduled = false;
  state.awaitDrain = 0;
  stream.emit('resume');
  flow(stream);
  if (state.flowing && !state.reading) stream.read(0);
}

Readable.prototype.pause = function () {
  debug('call pause flowing=%j', this._readableState.flowing);
  if (false !== this._readableState.flowing) {
    debug('pause');
    this._readableState.flowing = false;
    this.emit('pause');
  }
  return this;
};

function flow(stream) {
  var state = stream._readableState;
  debug('flow', state.flowing);
  while (state.flowing && stream.read() !== null) {}
}

// wrap an old-style stream as the async data source.
// This is *not* part of the readable stream interface.
// It is an ugly unfortunate mess of history.
Readable.prototype.wrap = function (stream) {
  var state = this._readableState;
  var paused = false;

  var self = this;
  stream.on('end', function () {
    debug('wrapped end');
    if (state.decoder && !state.ended) {
      var chunk = state.decoder.end();
      if (chunk && chunk.length) self.push(chunk);
    }

    self.push(null);
  });

  stream.on('data', function (chunk) {
    debug('wrapped data');
    if (state.decoder) chunk = state.decoder.write(chunk);

    // don't skip over falsy values in objectMode
    if (state.objectMode && (chunk === null || chunk === undefined)) return;else if (!state.objectMode && (!chunk || !chunk.length)) return;

    var ret = self.push(chunk);
    if (!ret) {
      paused = true;
      stream.pause();
    }
  });

  // proxy all the other methods.
  // important when wrapping filters and duplexes.
  for (var i in stream) {
    if (this[i] === undefined && typeof stream[i] === 'function') {
      this[i] = function (method) {
        return function () {
          return stream[method].apply(stream, arguments);
        };
      }(i);
    }
  }

  // proxy certain important events.
  for (var n = 0; n < kProxyEvents.length; n++) {
    stream.on(kProxyEvents[n], self.emit.bind(self, kProxyEvents[n]));
  }

  // when we try to consume some more bytes, simply unpause the
  // underlying stream.
  self._read = function (n) {
    debug('wrapped _read', n);
    if (paused) {
      paused = false;
      stream.resume();
    }
  };

  return self;
};

// exposed for testing purposes only.
Readable._fromList = fromList;

// Pluck off n bytes from an array of buffers.
// Length is the combined lengths of all the buffers in the list.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function fromList(n, state) {
  // nothing buffered
  if (state.length === 0) return null;

  var ret;
  if (state.objectMode) ret = state.buffer.shift();else if (!n || n >= state.length) {
    // read it all, truncate the list
    if (state.decoder) ret = state.buffer.join('');else if (state.buffer.length === 1) ret = state.buffer.head.data;else ret = state.buffer.concat(state.length);
    state.buffer.clear();
  } else {
    // read part of list
    ret = fromListPartial(n, state.buffer, state.decoder);
  }

  return ret;
}

// Extracts only enough buffered data to satisfy the amount requested.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function fromListPartial(n, list, hasStrings) {
  var ret;
  if (n < list.head.data.length) {
    // slice is the same for buffers and strings
    ret = list.head.data.slice(0, n);
    list.head.data = list.head.data.slice(n);
  } else if (n === list.head.data.length) {
    // first chunk is a perfect match
    ret = list.shift();
  } else {
    // result spans more than one buffer
    ret = hasStrings ? copyFromBufferString(n, list) : copyFromBuffer(n, list);
  }
  return ret;
}

// Copies a specified amount of characters from the list of buffered data
// chunks.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function copyFromBufferString(n, list) {
  var p = list.head;
  var c = 1;
  var ret = p.data;
  n -= ret.length;
  while (p = p.next) {
    var str = p.data;
    var nb = n > str.length ? str.length : n;
    if (nb === str.length) ret += str;else ret += str.slice(0, n);
    n -= nb;
    if (n === 0) {
      if (nb === str.length) {
        ++c;
        if (p.next) list.head = p.next;else list.head = list.tail = null;
      } else {
        list.head = p;
        p.data = str.slice(nb);
      }
      break;
    }
    ++c;
  }
  list.length -= c;
  return ret;
}

// Copies a specified amount of bytes from the list of buffered data chunks.
// This function is designed to be inlinable, so please take care when making
// changes to the function body.
function copyFromBuffer(n, list) {
  var ret = Buffer.allocUnsafe(n);
  var p = list.head;
  var c = 1;
  p.data.copy(ret);
  n -= p.data.length;
  while (p = p.next) {
    var buf = p.data;
    var nb = n > buf.length ? buf.length : n;
    buf.copy(ret, ret.length - n, 0, nb);
    n -= nb;
    if (n === 0) {
      if (nb === buf.length) {
        ++c;
        if (p.next) list.head = p.next;else list.head = list.tail = null;
      } else {
        list.head = p;
        p.data = buf.slice(nb);
      }
      break;
    }
    ++c;
  }
  list.length -= c;
  return ret;
}

function endReadable(stream) {
  var state = stream._readableState;

  // If we get here before consuming all the bytes, then that is a
  // bug in node.  Should never happen.
  if (state.length > 0) throw new Error('"endReadable()" called on non-empty stream');

  if (!state.endEmitted) {
    state.ended = true;
    processNextTick(endReadableNT, state, stream);
  }
}

function endReadableNT(state, stream) {
  // Check that we didn't get one last unshift.
  if (!state.endEmitted && state.length === 0) {
    state.endEmitted = true;
    stream.readable = false;
    stream.emit('end');
  }
}

function forEach(xs, f) {
  for (var i = 0, l = xs.length; i < l; i++) {
    f(xs[i], i);
  }
}

function indexOf(xs, x) {
  for (var i = 0, l = xs.length; i < l; i++) {
    if (xs[i] === x) return i;
  }
  return -1;
}
}).call(this,require('_process'))
},{"./_stream_duplex":19,"./internal/streams/BufferList":24,"./internal/streams/stream":25,"_process":7,"core-util-is":9,"events":4,"inherits":14,"isarray":15,"process-nextick-args":17,"safe-buffer":26,"string_decoder/":31,"util":2}],22:[function(require,module,exports){
// a transform stream is a readable/writable stream where you do
// something with the data.  Sometimes it's called a "filter",
// but that's not a great name for it, since that implies a thing where
// some bits pass through, and others are simply ignored.  (That would
// be a valid example of a transform, of course.)
//
// While the output is causally related to the input, it's not a
// necessarily symmetric or synchronous transformation.  For example,
// a zlib stream might take multiple plain-text writes(), and then
// emit a single compressed chunk some time in the future.
//
// Here's how this works:
//
// The Transform stream has all the aspects of the readable and writable
// stream classes.  When you write(chunk), that calls _write(chunk,cb)
// internally, and returns false if there's a lot of pending writes
// buffered up.  When you call read(), that calls _read(n) until
// there's enough pending readable data buffered up.
//
// In a transform stream, the written data is placed in a buffer.  When
// _read(n) is called, it transforms the queued up data, calling the
// buffered _write cb's as it consumes chunks.  If consuming a single
// written chunk would result in multiple output chunks, then the first
// outputted bit calls the readcb, and subsequent chunks just go into
// the read buffer, and will cause it to emit 'readable' if necessary.
//
// This way, back-pressure is actually determined by the reading side,
// since _read has to be called to start processing a new chunk.  However,
// a pathological inflate type of transform can cause excessive buffering
// here.  For example, imagine a stream where every byte of input is
// interpreted as an integer from 0-255, and then results in that many
// bytes of output.  Writing the 4 bytes {ff,ff,ff,ff} would result in
// 1kb of data being output.  In this case, you could write a very small
// amount of input, and end up with a very large amount of output.  In
// such a pathological inflating mechanism, there'd be no way to tell
// the system to stop doing the transform.  A single 4MB write could
// cause the system to run out of memory.
//
// However, even in such a pathological case, only a single written chunk
// would be consumed, and then the rest would wait (un-transformed) until
// the results of the previous transformed chunk were consumed.

'use strict';

module.exports = Transform;

var Duplex = require('./_stream_duplex');

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

util.inherits(Transform, Duplex);

function TransformState(stream) {
  this.afterTransform = function (er, data) {
    return afterTransform(stream, er, data);
  };

  this.needTransform = false;
  this.transforming = false;
  this.writecb = null;
  this.writechunk = null;
  this.writeencoding = null;
}

function afterTransform(stream, er, data) {
  var ts = stream._transformState;
  ts.transforming = false;

  var cb = ts.writecb;

  if (!cb) return stream.emit('error', new Error('no writecb in Transform class'));

  ts.writechunk = null;
  ts.writecb = null;

  if (data !== null && data !== undefined) stream.push(data);

  cb(er);

  var rs = stream._readableState;
  rs.reading = false;
  if (rs.needReadable || rs.length < rs.highWaterMark) {
    stream._read(rs.highWaterMark);
  }
}

function Transform(options) {
  if (!(this instanceof Transform)) return new Transform(options);

  Duplex.call(this, options);

  this._transformState = new TransformState(this);

  var stream = this;

  // start out asking for a readable event once data is transformed.
  this._readableState.needReadable = true;

  // we have implemented the _read method, and done the other things
  // that Readable wants before the first _read call, so unset the
  // sync guard flag.
  this._readableState.sync = false;

  if (options) {
    if (typeof options.transform === 'function') this._transform = options.transform;

    if (typeof options.flush === 'function') this._flush = options.flush;
  }

  // When the writable side finishes, then flush out anything remaining.
  this.once('prefinish', function () {
    if (typeof this._flush === 'function') this._flush(function (er, data) {
      done(stream, er, data);
    });else done(stream);
  });
}

Transform.prototype.push = function (chunk, encoding) {
  this._transformState.needTransform = false;
  return Duplex.prototype.push.call(this, chunk, encoding);
};

// This is the part where you do stuff!
// override this function in implementation classes.
// 'chunk' is an input chunk.
//
// Call `push(newChunk)` to pass along transformed output
// to the readable side.  You may call 'push' zero or more times.
//
// Call `cb(err)` when you are done with this chunk.  If you pass
// an error, then that'll put the hurt on the whole operation.  If you
// never call cb(), then you'll never get another chunk.
Transform.prototype._transform = function (chunk, encoding, cb) {
  throw new Error('_transform() is not implemented');
};

Transform.prototype._write = function (chunk, encoding, cb) {
  var ts = this._transformState;
  ts.writecb = cb;
  ts.writechunk = chunk;
  ts.writeencoding = encoding;
  if (!ts.transforming) {
    var rs = this._readableState;
    if (ts.needTransform || rs.needReadable || rs.length < rs.highWaterMark) this._read(rs.highWaterMark);
  }
};

// Doesn't matter what the args are here.
// _transform does all the work.
// That we got here means that the readable side wants more data.
Transform.prototype._read = function (n) {
  var ts = this._transformState;

  if (ts.writechunk !== null && ts.writecb && !ts.transforming) {
    ts.transforming = true;
    this._transform(ts.writechunk, ts.writeencoding, ts.afterTransform);
  } else {
    // mark that we need a transform, so that any data that comes in
    // will get processed, now that we've asked for it.
    ts.needTransform = true;
  }
};

function done(stream, er, data) {
  if (er) return stream.emit('error', er);

  if (data !== null && data !== undefined) stream.push(data);

  // if there's nothing in the write buffer, then that means
  // that nothing more will ever be provided
  var ws = stream._writableState;
  var ts = stream._transformState;

  if (ws.length) throw new Error('Calling transform done when ws.length != 0');

  if (ts.transforming) throw new Error('Calling transform done when still transforming');

  return stream.push(null);
}
},{"./_stream_duplex":19,"core-util-is":9,"inherits":14}],23:[function(require,module,exports){
(function (process){
// A bit simpler than readable streams.
// Implement an async ._write(chunk, encoding, cb), and it'll handle all
// the drain event emission and buffering.

'use strict';

module.exports = Writable;

/*<replacement>*/
var processNextTick = require('process-nextick-args');
/*</replacement>*/

/*<replacement>*/
var asyncWrite = !process.browser && ['v0.10', 'v0.9.'].indexOf(process.version.slice(0, 5)) > -1 ? setImmediate : processNextTick;
/*</replacement>*/

/*<replacement>*/
var Duplex;
/*</replacement>*/

Writable.WritableState = WritableState;

/*<replacement>*/
var util = require('core-util-is');
util.inherits = require('inherits');
/*</replacement>*/

/*<replacement>*/
var internalUtil = {
  deprecate: require('util-deprecate')
};
/*</replacement>*/

/*<replacement>*/
var Stream = require('./internal/streams/stream');
/*</replacement>*/

/*<replacement>*/
var Buffer = require('safe-buffer').Buffer;
/*</replacement>*/

util.inherits(Writable, Stream);

function nop() {}

function WriteReq(chunk, encoding, cb) {
  this.chunk = chunk;
  this.encoding = encoding;
  this.callback = cb;
  this.next = null;
}

function WritableState(options, stream) {
  Duplex = Duplex || require('./_stream_duplex');

  options = options || {};

  // object stream flag to indicate whether or not this stream
  // contains buffers or objects.
  this.objectMode = !!options.objectMode;

  if (stream instanceof Duplex) this.objectMode = this.objectMode || !!options.writableObjectMode;

  // the point at which write() starts returning false
  // Note: 0 is a valid value, means that we always return false if
  // the entire buffer is not flushed immediately on write()
  var hwm = options.highWaterMark;
  var defaultHwm = this.objectMode ? 16 : 16 * 1024;
  this.highWaterMark = hwm || hwm === 0 ? hwm : defaultHwm;

  // cast to ints.
  this.highWaterMark = ~~this.highWaterMark;

  // drain event flag.
  this.needDrain = false;
  // at the start of calling end()
  this.ending = false;
  // when end() has been called, and returned
  this.ended = false;
  // when 'finish' is emitted
  this.finished = false;

  // should we decode strings into buffers before passing to _write?
  // this is here so that some node-core streams can optimize string
  // handling at a lower level.
  var noDecode = options.decodeStrings === false;
  this.decodeStrings = !noDecode;

  // Crypto is kind of old and crusty.  Historically, its default string
  // encoding is 'binary' so we have to make this configurable.
  // Everything else in the universe uses 'utf8', though.
  this.defaultEncoding = options.defaultEncoding || 'utf8';

  // not an actual buffer we keep track of, but a measurement
  // of how much we're waiting to get pushed to some underlying
  // socket or file.
  this.length = 0;

  // a flag to see when we're in the middle of a write.
  this.writing = false;

  // when true all writes will be buffered until .uncork() call
  this.corked = 0;

  // a flag to be able to tell if the onwrite cb is called immediately,
  // or on a later tick.  We set this to true at first, because any
  // actions that shouldn't happen until "later" should generally also
  // not happen before the first write call.
  this.sync = true;

  // a flag to know if we're processing previously buffered items, which
  // may call the _write() callback in the same tick, so that we don't
  // end up in an overlapped onwrite situation.
  this.bufferProcessing = false;

  // the callback that's passed to _write(chunk,cb)
  this.onwrite = function (er) {
    onwrite(stream, er);
  };

  // the callback that the user supplies to write(chunk,encoding,cb)
  this.writecb = null;

  // the amount that is being written when _write is called.
  this.writelen = 0;

  this.bufferedRequest = null;
  this.lastBufferedRequest = null;

  // number of pending user-supplied write callbacks
  // this must be 0 before 'finish' can be emitted
  this.pendingcb = 0;

  // emit prefinish if the only thing we're waiting for is _write cbs
  // This is relevant for synchronous Transform streams
  this.prefinished = false;

  // True if the error was already emitted and should not be thrown again
  this.errorEmitted = false;

  // count buffered requests
  this.bufferedRequestCount = 0;

  // allocate the first CorkedRequest, there is always
  // one allocated and free to use, and we maintain at most two
  this.corkedRequestsFree = new CorkedRequest(this);
}

WritableState.prototype.getBuffer = function getBuffer() {
  var current = this.bufferedRequest;
  var out = [];
  while (current) {
    out.push(current);
    current = current.next;
  }
  return out;
};

(function () {
  try {
    Object.defineProperty(WritableState.prototype, 'buffer', {
      get: internalUtil.deprecate(function () {
        return this.getBuffer();
      }, '_writableState.buffer is deprecated. Use _writableState.getBuffer ' + 'instead.')
    });
  } catch (_) {}
})();

// Test _writableState for inheritance to account for Duplex streams,
// whose prototype chain only points to Readable.
var realHasInstance;
if (typeof Symbol === 'function' && Symbol.hasInstance && typeof Function.prototype[Symbol.hasInstance] === 'function') {
  realHasInstance = Function.prototype[Symbol.hasInstance];
  Object.defineProperty(Writable, Symbol.hasInstance, {
    value: function (object) {
      if (realHasInstance.call(this, object)) return true;

      return object && object._writableState instanceof WritableState;
    }
  });
} else {
  realHasInstance = function (object) {
    return object instanceof this;
  };
}

function Writable(options) {
  Duplex = Duplex || require('./_stream_duplex');

  // Writable ctor is applied to Duplexes, too.
  // `realHasInstance` is necessary because using plain `instanceof`
  // would return false, as no `_writableState` property is attached.

  // Trying to use the custom `instanceof` for Writable here will also break the
  // Node.js LazyTransform implementation, which has a non-trivial getter for
  // `_writableState` that would lead to infinite recursion.
  if (!realHasInstance.call(Writable, this) && !(this instanceof Duplex)) {
    return new Writable(options);
  }

  this._writableState = new WritableState(options, this);

  // legacy.
  this.writable = true;

  if (options) {
    if (typeof options.write === 'function') this._write = options.write;

    if (typeof options.writev === 'function') this._writev = options.writev;
  }

  Stream.call(this);
}

// Otherwise people can pipe Writable streams, which is just wrong.
Writable.prototype.pipe = function () {
  this.emit('error', new Error('Cannot pipe, not readable'));
};

function writeAfterEnd(stream, cb) {
  var er = new Error('write after end');
  // TODO: defer error events consistently everywhere, not just the cb
  stream.emit('error', er);
  processNextTick(cb, er);
}

// Checks that a user-supplied chunk is valid, especially for the particular
// mode the stream is in. Currently this means that `null` is never accepted
// and undefined/non-string values are only allowed in object mode.
function validChunk(stream, state, chunk, cb) {
  var valid = true;
  var er = false;

  if (chunk === null) {
    er = new TypeError('May not write null values to stream');
  } else if (typeof chunk !== 'string' && chunk !== undefined && !state.objectMode) {
    er = new TypeError('Invalid non-string/buffer chunk');
  }
  if (er) {
    stream.emit('error', er);
    processNextTick(cb, er);
    valid = false;
  }
  return valid;
}

Writable.prototype.write = function (chunk, encoding, cb) {
  var state = this._writableState;
  var ret = false;
  var isBuf = Buffer.isBuffer(chunk);

  if (typeof encoding === 'function') {
    cb = encoding;
    encoding = null;
  }

  if (isBuf) encoding = 'buffer';else if (!encoding) encoding = state.defaultEncoding;

  if (typeof cb !== 'function') cb = nop;

  if (state.ended) writeAfterEnd(this, cb);else if (isBuf || validChunk(this, state, chunk, cb)) {
    state.pendingcb++;
    ret = writeOrBuffer(this, state, isBuf, chunk, encoding, cb);
  }

  return ret;
};

Writable.prototype.cork = function () {
  var state = this._writableState;

  state.corked++;
};

Writable.prototype.uncork = function () {
  var state = this._writableState;

  if (state.corked) {
    state.corked--;

    if (!state.writing && !state.corked && !state.finished && !state.bufferProcessing && state.bufferedRequest) clearBuffer(this, state);
  }
};

Writable.prototype.setDefaultEncoding = function setDefaultEncoding(encoding) {
  // node::ParseEncoding() requires lower case.
  if (typeof encoding === 'string') encoding = encoding.toLowerCase();
  if (!(['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', 'raw'].indexOf((encoding + '').toLowerCase()) > -1)) throw new TypeError('Unknown encoding: ' + encoding);
  this._writableState.defaultEncoding = encoding;
  return this;
};

function decodeChunk(state, chunk, encoding) {
  if (!state.objectMode && state.decodeStrings !== false && typeof chunk === 'string') {
    chunk = Buffer.from(chunk, encoding);
  }
  return chunk;
}

// if we're already writing something, then just put this
// in the queue, and wait our turn.  Otherwise, call _write
// If we return false, then we need a drain event, so set that flag.
function writeOrBuffer(stream, state, isBuf, chunk, encoding, cb) {
  if (!isBuf) {
    chunk = decodeChunk(state, chunk, encoding);
    if (Buffer.isBuffer(chunk)) encoding = 'buffer';
  }
  var len = state.objectMode ? 1 : chunk.length;

  state.length += len;

  var ret = state.length < state.highWaterMark;
  // we must ensure that previous needDrain will not be reset to false.
  if (!ret) state.needDrain = true;

  if (state.writing || state.corked) {
    var last = state.lastBufferedRequest;
    state.lastBufferedRequest = new WriteReq(chunk, encoding, cb);
    if (last) {
      last.next = state.lastBufferedRequest;
    } else {
      state.bufferedRequest = state.lastBufferedRequest;
    }
    state.bufferedRequestCount += 1;
  } else {
    doWrite(stream, state, false, len, chunk, encoding, cb);
  }

  return ret;
}

function doWrite(stream, state, writev, len, chunk, encoding, cb) {
  state.writelen = len;
  state.writecb = cb;
  state.writing = true;
  state.sync = true;
  if (writev) stream._writev(chunk, state.onwrite);else stream._write(chunk, encoding, state.onwrite);
  state.sync = false;
}

function onwriteError(stream, state, sync, er, cb) {
  --state.pendingcb;
  if (sync) processNextTick(cb, er);else cb(er);

  stream._writableState.errorEmitted = true;
  stream.emit('error', er);
}

function onwriteStateUpdate(state) {
  state.writing = false;
  state.writecb = null;
  state.length -= state.writelen;
  state.writelen = 0;
}

function onwrite(stream, er) {
  var state = stream._writableState;
  var sync = state.sync;
  var cb = state.writecb;

  onwriteStateUpdate(state);

  if (er) onwriteError(stream, state, sync, er, cb);else {
    // Check if we're actually ready to finish, but don't emit yet
    var finished = needFinish(state);

    if (!finished && !state.corked && !state.bufferProcessing && state.bufferedRequest) {
      clearBuffer(stream, state);
    }

    if (sync) {
      /*<replacement>*/
      asyncWrite(afterWrite, stream, state, finished, cb);
      /*</replacement>*/
    } else {
      afterWrite(stream, state, finished, cb);
    }
  }
}

function afterWrite(stream, state, finished, cb) {
  if (!finished) onwriteDrain(stream, state);
  state.pendingcb--;
  cb();
  finishMaybe(stream, state);
}

// Must force callback to be called on nextTick, so that we don't
// emit 'drain' before the write() consumer gets the 'false' return
// value, and has a chance to attach a 'drain' listener.
function onwriteDrain(stream, state) {
  if (state.length === 0 && state.needDrain) {
    state.needDrain = false;
    stream.emit('drain');
  }
}

// if there's something in the buffer waiting, then process it
function clearBuffer(stream, state) {
  state.bufferProcessing = true;
  var entry = state.bufferedRequest;

  if (stream._writev && entry && entry.next) {
    // Fast case, write everything using _writev()
    var l = state.bufferedRequestCount;
    var buffer = new Array(l);
    var holder = state.corkedRequestsFree;
    holder.entry = entry;

    var count = 0;
    while (entry) {
      buffer[count] = entry;
      entry = entry.next;
      count += 1;
    }

    doWrite(stream, state, true, state.length, buffer, '', holder.finish);

    // doWrite is almost always async, defer these to save a bit of time
    // as the hot path ends with doWrite
    state.pendingcb++;
    state.lastBufferedRequest = null;
    if (holder.next) {
      state.corkedRequestsFree = holder.next;
      holder.next = null;
    } else {
      state.corkedRequestsFree = new CorkedRequest(state);
    }
  } else {
    // Slow case, write chunks one-by-one
    while (entry) {
      var chunk = entry.chunk;
      var encoding = entry.encoding;
      var cb = entry.callback;
      var len = state.objectMode ? 1 : chunk.length;

      doWrite(stream, state, false, len, chunk, encoding, cb);
      entry = entry.next;
      // if we didn't call the onwrite immediately, then
      // it means that we need to wait until it does.
      // also, that means that the chunk and cb are currently
      // being processed, so move the buffer counter past them.
      if (state.writing) {
        break;
      }
    }

    if (entry === null) state.lastBufferedRequest = null;
  }

  state.bufferedRequestCount = 0;
  state.bufferedRequest = entry;
  state.bufferProcessing = false;
}

Writable.prototype._write = function (chunk, encoding, cb) {
  cb(new Error('_write() is not implemented'));
};

Writable.prototype._writev = null;

Writable.prototype.end = function (chunk, encoding, cb) {
  var state = this._writableState;

  if (typeof chunk === 'function') {
    cb = chunk;
    chunk = null;
    encoding = null;
  } else if (typeof encoding === 'function') {
    cb = encoding;
    encoding = null;
  }

  if (chunk !== null && chunk !== undefined) this.write(chunk, encoding);

  // .end() fully uncorks
  if (state.corked) {
    state.corked = 1;
    this.uncork();
  }

  // ignore unnecessary end() calls.
  if (!state.ending && !state.finished) endWritable(this, state, cb);
};

function needFinish(state) {
  return state.ending && state.length === 0 && state.bufferedRequest === null && !state.finished && !state.writing;
}

function prefinish(stream, state) {
  if (!state.prefinished) {
    state.prefinished = true;
    stream.emit('prefinish');
  }
}

function finishMaybe(stream, state) {
  var need = needFinish(state);
  if (need) {
    if (state.pendingcb === 0) {
      prefinish(stream, state);
      state.finished = true;
      stream.emit('finish');
    } else {
      prefinish(stream, state);
    }
  }
  return need;
}

function endWritable(stream, state, cb) {
  state.ending = true;
  finishMaybe(stream, state);
  if (cb) {
    if (state.finished) processNextTick(cb);else stream.once('finish', cb);
  }
  state.ended = true;
  stream.writable = false;
}

// It seems a linked list but it is not
// there will be only 2 of these for each stream
function CorkedRequest(state) {
  var _this = this;

  this.next = null;
  this.entry = null;
  this.finish = function (err) {
    var entry = _this.entry;
    _this.entry = null;
    while (entry) {
      var cb = entry.callback;
      state.pendingcb--;
      cb(err);
      entry = entry.next;
    }
    if (state.corkedRequestsFree) {
      state.corkedRequestsFree.next = _this;
    } else {
      state.corkedRequestsFree = _this;
    }
  };
}
}).call(this,require('_process'))
},{"./_stream_duplex":19,"./internal/streams/stream":25,"_process":7,"core-util-is":9,"inherits":14,"process-nextick-args":17,"safe-buffer":26,"util-deprecate":33}],24:[function(require,module,exports){
'use strict';

/*<replacement>*/

var Buffer = require('safe-buffer').Buffer;
/*</replacement>*/

module.exports = BufferList;

function BufferList() {
  this.head = null;
  this.tail = null;
  this.length = 0;
}

BufferList.prototype.push = function (v) {
  var entry = { data: v, next: null };
  if (this.length > 0) this.tail.next = entry;else this.head = entry;
  this.tail = entry;
  ++this.length;
};

BufferList.prototype.unshift = function (v) {
  var entry = { data: v, next: this.head };
  if (this.length === 0) this.tail = entry;
  this.head = entry;
  ++this.length;
};

BufferList.prototype.shift = function () {
  if (this.length === 0) return;
  var ret = this.head.data;
  if (this.length === 1) this.head = this.tail = null;else this.head = this.head.next;
  --this.length;
  return ret;
};

BufferList.prototype.clear = function () {
  this.head = this.tail = null;
  this.length = 0;
};

BufferList.prototype.join = function (s) {
  if (this.length === 0) return '';
  var p = this.head;
  var ret = '' + p.data;
  while (p = p.next) {
    ret += s + p.data;
  }return ret;
};

BufferList.prototype.concat = function (n) {
  if (this.length === 0) return Buffer.alloc(0);
  if (this.length === 1) return this.head.data;
  var ret = Buffer.allocUnsafe(n >>> 0);
  var p = this.head;
  var i = 0;
  while (p) {
    p.data.copy(ret, i);
    i += p.data.length;
    p = p.next;
  }
  return ret;
};
},{"safe-buffer":26}],25:[function(require,module,exports){
module.exports = require('events').EventEmitter;

},{"events":4}],26:[function(require,module,exports){
module.exports = require('buffer')

},{"buffer":3}],27:[function(require,module,exports){
exports = module.exports = require('./lib/_stream_readable.js');
exports.Stream = exports;
exports.Readable = exports;
exports.Writable = require('./lib/_stream_writable.js');
exports.Duplex = require('./lib/_stream_duplex.js');
exports.Transform = require('./lib/_stream_transform.js');
exports.PassThrough = require('./lib/_stream_passthrough.js');

},{"./lib/_stream_duplex.js":19,"./lib/_stream_passthrough.js":20,"./lib/_stream_readable.js":21,"./lib/_stream_transform.js":22,"./lib/_stream_writable.js":23}],28:[function(require,module,exports){
/* eslint-disable node/no-deprecated-api */
var buffer = require('buffer')
var Buffer = buffer.Buffer

if (Buffer.from && Buffer.alloc && Buffer.allocUnsafe && Buffer.allocUnsafeSlow) {
  module.exports = buffer
} else {
  // Copy properties from require('buffer')
  Object.keys(buffer).forEach(function (prop) {
    exports[prop] = buffer[prop]
  })
  exports.Buffer = SafeBuffer
}

function SafeBuffer (arg, encodingOrOffset, length) {
  return Buffer(arg, encodingOrOffset, length)
}

// Copy static methods from Buffer
Object.keys(Buffer).forEach(function (prop) {
  SafeBuffer[prop] = Buffer[prop]
})

SafeBuffer.from = function (arg, encodingOrOffset, length) {
  if (typeof arg === 'number') {
    throw new TypeError('Argument must not be a number')
  }
  return Buffer(arg, encodingOrOffset, length)
}

SafeBuffer.alloc = function (size, fill, encoding) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  var buf = Buffer(size)
  if (fill !== undefined) {
    if (typeof encoding === 'string') {
      buf.fill(fill, encoding)
    } else {
      buf.fill(fill)
    }
  } else {
    buf.fill(0)
  }
  return buf
}

SafeBuffer.allocUnsafe = function (size) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  return Buffer(size)
}

SafeBuffer.allocUnsafeSlow = function (size) {
  if (typeof size !== 'number') {
    throw new TypeError('Argument must be a number')
  }
  return buffer.SlowBuffer(size)
}

},{"buffer":3}],29:[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: parts[1],
    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);
  }
  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) {
      bandwidth = parseInt(bandwidth[0].substr(5), 10);
    }
    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 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(parts) {
    return parts.attribute === 'msid';
  });
  if (planB.length > 0) {
    parts = planB[0].value.split(' ');
    return {stream: parts[0], track: parts[1]};
  }
};

SDPUtils.writeSessionBoilerplate = function() {
  // FIXME: sess-id should be an NTP timestamp.
  return 'v=0\r\n' +
      'o=thisisadapterortc 8169639915646943137 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;

},{}],30:[function(require,module,exports){
(function (Buffer){
module.exports = Peer

var debug = require('debug')('simple-peer')
var getBrowserRTC = require('get-browser-rtc')
var inherits = require('inherits')
var randombytes = require('randombytes')
var stream = require('readable-stream')

var MAX_BUFFERED_AMOUNT = 64 * 1024

inherits(Peer, stream.Duplex)

/**
 * WebRTC peer connection. Same API as node core `net.Socket`, plus a few extra methods.
 * Duplex stream.
 * @param {Object} opts
 */
function Peer (opts) {
  var self = this
  if (!(self instanceof Peer)) return new Peer(opts)

  self._id = randombytes(4).toString('hex').slice(0, 7)
  self._debug('new peer %o', opts)

  opts = Object.assign({
    allowHalfOpen: false
  }, opts)

  stream.Duplex.call(self, opts)

  self.channelName = opts.initiator
    ? opts.channelName || randombytes(20).toString('hex')
    : null

  // Needed by _transformConstraints, so set this early
  self._isChromium = typeof window !== 'undefined' && !!window.webkitRTCPeerConnection

  self.initiator = opts.initiator || false
  self.channelConfig = opts.channelConfig || Peer.channelConfig
  self.config = opts.config || Peer.config
  self.constraints = self._transformConstraints(opts.constraints || Peer.constraints)
  self.offerConstraints = self._transformConstraints(opts.offerConstraints || {})
  self.answerConstraints = self._transformConstraints(opts.answerConstraints || {})
  self.reconnectTimer = opts.reconnectTimer || false
  self.sdpTransform = opts.sdpTransform || function (sdp) { return sdp }
  self.stream = opts.stream || false
  self.trickle = opts.trickle !== undefined ? opts.trickle : true

  self.destroyed = false
  self.connected = false

  self.remoteAddress = undefined
  self.remoteFamily = undefined
  self.remotePort = undefined
  self.localAddress = undefined
  self.localPort = undefined

  self._wrtc = (opts.wrtc && typeof opts.wrtc === 'object')
    ? opts.wrtc
    : getBrowserRTC()

  if (!self._wrtc) {
    if (typeof window === 'undefined') {
      throw new Error('No WebRTC support: Specify `opts.wrtc` option in this environment')
    } else {
      throw new Error('No WebRTC support: Not a supported browser')
    }
  }

  self._pcReady = false
  self._channelReady = false
  self._iceComplete = false // ice candidate trickle done (got null candidate)
  self._channel = null
  self._pendingCandidates = []
  self._previousStreams = []

  self._chunk = null
  self._cb = null
  self._interval = null
  self._reconnectTimeout = null

  self._pc = new (self._wrtc.RTCPeerConnection)(self.config, self.constraints)

  // We prefer feature detection whenever possible, but sometimes that's not
  // possible for certain implementations.
  self._isWrtc = Array.isArray(self._pc.RTCIceConnectionStates)
  self._isReactNativeWebrtc = typeof self._pc._peerConnectionId === 'number'

  self._pc.oniceconnectionstatechange = function () {
    self._onIceStateChange()
  }
  self._pc.onicegatheringstatechange = function () {
    self._onIceStateChange()
  }
  self._pc.onsignalingstatechange = function () {
    self._onSignalingStateChange()
  }
  self._pc.onicecandidate = function (event) {
    self._onIceCandidate(event)
  }

  // Other spec events, unused by this implementation:
  // - onconnectionstatechange
  // - onicecandidateerror
  // - onfingerprintfailure

  if (self.initiator) {
    var createdOffer = false
    self._pc.onnegotiationneeded = function () {
      if (!createdOffer) self._createOffer()
      createdOffer = true
    }

    self._setupData({
      channel: self._pc.createDataChannel(self.channelName, self.channelConfig)
    })
  } else {
    self._pc.ondatachannel = function (event) {
      self._setupData(event)
    }
  }

  if ('addTrack' in self._pc) {
    // WebRTC Spec, Firefox
    if (self.stream) {
      self.stream.getTracks().forEach(function (track) {
        self._pc.addTrack(track, self.stream)
      })
    }
    self._pc.ontrack = function (event) {
      self._onTrack(event)
    }
  } else {
    // Chrome, etc. This can be removed once all browsers support `ontrack`
    if (self.stream) self._pc.addStream(self.stream)
    self._pc.onaddstream = function (event) {
      self._onAddStream(event)
    }
  }

  // HACK: wrtc doesn't fire the 'negotionneeded' event
  if (self.initiator && self._isWrtc) {
    self._pc.onnegotiationneeded()
  }

  self._onFinishBound = function () {
    self._onFinish()
  }
  self.once('finish', self._onFinishBound)
}

Peer.WEBRTC_SUPPORT = !!getBrowserRTC()

/**
 * Expose config, constraints, and data channel config for overriding all Peer
 * instances. Otherwise, just set opts.config, opts.constraints, or opts.channelConfig
 * when constructing a Peer.
 */
Peer.config = {
  iceServers: [
    {
      urls: 'stun:stun.l.google.com:19302'
    },
    {
      urls: 'stun:global.stun.twilio.com:3478?transport=udp'
    }
  ]
}
Peer.constraints = {}
Peer.channelConfig = {}

Object.defineProperty(Peer.prototype, 'bufferSize', {
  get: function () {
    var self = this
    return (self._channel && self._channel.bufferedAmount) || 0
  }
})

Peer.prototype.address = function () {
  var self = this
  return { port: self.localPort, family: 'IPv4', address: self.localAddress }
}

Peer.prototype.signal = function (data) {
  var self = this
  if (self.destroyed) throw new Error('cannot signal after peer is destroyed')
  if (typeof data === 'string') {
    try {
      data = JSON.parse(data)
    } catch (err) {
      data = {}
    }
  }
  self._debug('signal()')

  if (data.candidate) {
    if (self._pc.remoteDescription) self._addIceCandidate(data.candidate)
    else self._pendingCandidates.push(data.candidate)
  }
  if (data.sdp) {
    self._pc.setRemoteDescription(new (self._wrtc.RTCSessionDescription)(data), function () {
      if (self.destroyed) return

      self._pendingCandidates.forEach(function (candidate) {
        self._addIceCandidate(candidate)
      })
      self._pendingCandidates = []

      if (self._pc.remoteDescription.type === 'offer') self._createAnswer()
    }, function (err) { self._destroy(err) })
  }
  if (!data.sdp && !data.candidate) {
    self._destroy(new Error('signal() called with invalid signal data'))
  }
}

Peer.prototype._addIceCandidate = function (candidate) {
  var self = this
  try {
    self._pc.addIceCandidate(
      new self._wrtc.RTCIceCandidate(candidate),
      noop,
      function (err) { self._destroy(err) }
    )
  } catch (err) {
    self._destroy(new Error('error adding candidate: ' + err.message))
  }
}

/**
 * Send text/binary data to the remote peer.
 * @param {TypedArrayView|ArrayBuffer|Buffer|string|Blob|Object} chunk
 */
Peer.prototype.send = function (chunk) {
  var self = this

  // HACK: `wrtc` module crashes on Node.js Buffer, so convert to Uint8Array
  // See: https://github.com/feross/simple-peer/issues/60
  if (self._isWrtc && Buffer.isBuffer(chunk)) {
    chunk = new Uint8Array(chunk)
  }

  self._channel.send(chunk)
}

Peer.prototype.destroy = function (onclose) {
  var self = this
  self._destroy(null, onclose)
}

Peer.prototype._destroy = function (err, onclose) {
  var self = this
  if (self.destroyed) return
  if (onclose) self.once('close', onclose)

  self._debug('destroy (error: %s)', err && (err.message || err))

  self.readable = self.writable = false

  if (!self._readableState.ended) self.push(null)
  if (!self._writableState.finished) self.end()

  self.destroyed = true
  self.connected = false
  self._pcReady = false
  self._channelReady = false
  self._previousStreams = null

  clearInterval(self._interval)
  clearTimeout(self._reconnectTimeout)
  self._interval = null
  self._reconnectTimeout = null
  self._chunk = null
  self._cb = null

  if (self._onFinishBound) self.removeListener('finish', self._onFinishBound)
  self._onFinishBound = null

  if (self._pc) {
    try {
      self._pc.close()
    } catch (err) {}

    self._pc.oniceconnectionstatechange = null
    self._pc.onicegatheringstatechange = null
    self._pc.onsignalingstatechange = null
    self._pc.onicecandidate = null
    if ('addTrack' in self._pc) {
      self._pc.ontrack = null
    } else {
      self._pc.onaddstream = null
    }
    self._pc.onnegotiationneeded = null
    self._pc.ondatachannel = null
  }

  if (self._channel) {
    try {
      self._channel.close()
    } catch (err) {}

    self._channel.onmessage = null
    self._channel.onopen = null
    self._channel.onclose = null
    self._channel.onerror = null
  }
  self._pc = null
  self._channel = null

  if (err) self.emit('error', err)
  self.emit('close')
}

Peer.prototype._setupData = function (event) {
  var self = this
  if (!event.channel) {
    // In some situations `pc.createDataChannel()` returns `undefined` (in wrtc),
    // which is invalid behavior. Handle it gracefully.
    // See: https://github.com/feross/simple-peer/issues/163
    return self._destroy(new Error('Data channel event is missing `channel` property'))
  }

  self._channel = event.channel
  self._channel.binaryType = 'arraybuffer'

  if (typeof self._channel.bufferedAmountLowThreshold === 'number') {
    self._channel.bufferedAmountLowThreshold = MAX_BUFFERED_AMOUNT
  }

  self.channelName = self._channel.label

  self._channel.onmessage = function (event) {
    self._onChannelMessage(event)
  }
  self._channel.onbufferedamountlow = function () {
    self._onChannelBufferedAmountLow()
  }
  self._channel.onopen = function () {
    self._onChannelOpen()
  }
  self._channel.onclose = function () {
    self._onChannelClose()
  }
  self._channel.onerror = function (err) {
    self._destroy(err)
  }
}

Peer.prototype._read = function () {}

Peer.prototype._write = function (chunk, encoding, cb) {
  var self = this
  if (self.destroyed) return cb(new Error('cannot write after peer is destroyed'))

  if (self.connected) {
    try {
      self.send(chunk)
    } catch (err) {
      return self._destroy(err)
    }
    if (self._channel.bufferedAmount > MAX_BUFFERED_AMOUNT) {
      self._debug('start backpressure: bufferedAmount %d', self._channel.bufferedAmount)
      self._cb = cb
    } else {
      cb(null)
    }
  } else {
    self._debug('write before connect')
    self._chunk = chunk
    self._cb = cb
  }
}

// When stream finishes writing, close socket. Half open connections are not
// supported.
Peer.prototype._onFinish = function () {
  var self = this
  if (self.destroyed) return

  if (self.connected) {
    destroySoon()
  } else {
    self.once('connect', destroySoon)
  }

  // Wait a bit before destroying so the socket flushes.
  // TODO: is there a more reliable way to accomplish this?
  function destroySoon () {
    setTimeout(function () {
      self._destroy()
    }, 1000)
  }
}

Peer.prototype._createOffer = function () {
  var self = this
  if (self.destroyed) return

  self._pc.createOffer(function (offer) {
    if (self.destroyed) return
    offer.sdp = self.sdpTransform(offer.sdp)
    self._pc.setLocalDescription(offer, onSuccess, onError)

    function onSuccess () {
      if (self.destroyed) return
      if (self.trickle || self._iceComplete) sendOffer()
      else self.once('_iceComplete', sendOffer) // wait for candidates
    }

    function onError (err) {
      self._destroy(err)
    }

    function sendOffer () {
      var signal = self._pc.localDescription || offer
      self._debug('signal')
      self.emit('signal', {
        type: signal.type,
        sdp: signal.sdp
      })
    }
  }, function (err) { self._destroy(err) }, self.offerConstraints)
}

Peer.prototype._createAnswer = function () {
  var self = this
  if (self.destroyed) return

  self._pc.createAnswer(function (answer) {
    if (self.destroyed) return
    answer.sdp = self.sdpTransform(answer.sdp)
    self._pc.setLocalDescription(answer, onSuccess, onError)

    function onSuccess () {
      if (self.destroyed) return
      if (self.trickle || self._iceComplete) sendAnswer()
      else self.once('_iceComplete', sendAnswer)
    }

    function onError (err) {
      self._destroy(err)
    }

    function sendAnswer () {
      var signal = self._pc.localDescription || answer
      self._debug('signal')
      self.emit('signal', {
        type: signal.type,
        sdp: signal.sdp
      })
    }
  }, function (err) { self._destroy(err) }, self.answerConstraints)
}

Peer.prototype._onIceStateChange = function () {
  var self = this
  if (self.destroyed) return
  var iceConnectionState = self._pc.iceConnectionState
  var iceGatheringState = self._pc.iceGatheringState

  self._debug(
    'iceStateChange (connection: %s) (gathering: %s)',
    iceConnectionState,
    iceGatheringState
  )
  self.emit('iceStateChange', iceConnectionState, iceGatheringState)

  if (iceConnectionState === 'connected' || iceConnectionState === 'completed') {
    clearTimeout(self._reconnectTimeout)
    self._pcReady = true
    self._maybeReady()
  }
  if (iceConnectionState === 'disconnected') {
    if (self.reconnectTimer) {
      // If user has set `opt.reconnectTimer`, allow time for ICE to attempt a reconnect
      clearTimeout(self._reconnectTimeout)
      self._reconnectTimeout = setTimeout(function () {
        self._destroy()
      }, self.reconnectTimer)
    } else {
      self._destroy()
    }
  }
  if (iceConnectionState === 'failed') {
    self._destroy(new Error('Ice connection failed.'))
  }
  if (iceConnectionState === 'closed') {
    self._destroy()
  }
}

Peer.prototype.getStats = function (cb) {
  var self = this

  // Promise-based getStats() (standard)
  if (self._pc.getStats.length === 0) {
    self._pc.getStats().then(function (res) {
      var reports = []
      res.forEach(function (report) {
        reports.push(report)
      })
      cb(null, reports)
    }, function (err) { cb(err) })

  // Two-parameter callback-based getStats() (deprecated, former standard)
  } else if (self._isReactNativeWebrtc) {
    self._pc.getStats(null, function (res) {
      var reports = []
      res.forEach(function (report) {
        reports.push(report)
      })
      cb(null, reports)
    }, function (err) { cb(err) })

  // Single-parameter callback-based getStats() (non-standard)
  } else if (self._pc.getStats.length > 0) {
    self._pc.getStats(function (res) {
      var reports = []
      res.result().forEach(function (result) {
        var report = {}
        result.names().forEach(function (name) {
          report[name] = result.stat(name)
        })
        report.id = result.id
        report.type = result.type
        report.timestamp = result.timestamp
        reports.push(report)
      })
      cb(null, reports)
    }, function (err) { cb(err) })

  // Unknown browser, skip getStats() since it's anyone's guess which style of
  // getStats() they implement.
  } else {
    cb(null, [])
  }
}

Peer.prototype._maybeReady = function () {
  var self = this
  self._debug('maybeReady pc %s channel %s', self._pcReady, self._channelReady)
  if (self.connected || self._connecting || !self._pcReady || !self._channelReady) return
  self._connecting = true

  self.getStats(function (err, items) {
    if (self.destroyed) return

    // Treat getStats error as non-fatal. It's not essential.
    if (err) items = []

    self._connecting = false
    self.connected = true

    var remoteCandidates = {}
    var localCandidates = {}
    var candidatePairs = {}

    items.forEach(function (item) {
      // TODO: Once all browsers support the hyphenated stats report types, remove
      // the non-hypenated ones
      if (item.type === 'remotecandidate' || item.type === 'remote-candidate') {
        remoteCandidates[item.id] = item
      }
      if (item.type === 'localcandidate' || item.type === 'local-candidate') {
        localCandidates[item.id] = item
      }
      if (item.type === 'candidatepair' || item.type === 'candidate-pair') {
        candidatePairs[item.id] = item
      }
    })

    items.forEach(function (item) {
      // Spec-compliant
      if (item.type === 'transport') {
        setSelectedCandidatePair(candidatePairs[item.selectedCandidatePairId])
      }

      // Old implementations
      if (
        (item.type === 'googCandidatePair' && item.googActiveConnection === 'true') ||
        ((item.type === 'candidatepair' || item.type === 'candidate-pair') && item.selected)
      ) {
        setSelectedCandidatePair(item)
      }
    })

    function setSelectedCandidatePair (selectedCandidatePair) {
      var local = localCandidates[selectedCandidatePair.localCandidateId]

      if (local && local.ip) {
        // Spec
        self.localAddress = local.ip
        self.localPort = Number(local.port)
      } else if (local && local.ipAddress) {
        // Firefox
        self.localAddress = local.ipAddress
        self.localPort = Number(local.portNumber)
      } else if (typeof selectedCandidatePair.googLocalAddress === 'string') {
        // TODO: remove this once Chrome 58 is released
        local = selectedCandidatePair.googLocalAddress.split(':')
        self.localAddress = local[0]
        self.localPort = Number(local[1])
      }

      var remote = remoteCandidates[selectedCandidatePair.remoteCandidateId]

      if (remote && remote.ip) {
        // Spec
        self.remoteAddress = remote.ip
        self.remotePort = Number(remote.port)
      } else if (remote && remote.ipAddress) {
        // Firefox
        self.remoteAddress = remote.ipAddress
        self.remotePort = Number(remote.portNumber)
      } else if (typeof selectedCandidatePair.googRemoteAddress === 'string') {
        // TODO: remove this once Chrome 58 is released
        remote = selectedCandidatePair.googRemoteAddress.split(':')
        self.remoteAddress = remote[0]
        self.remotePort = Number(remote[1])
      }
      self.remoteFamily = 'IPv4'

      self._debug(
        'connect local: %s:%s remote: %s:%s',
        self.localAddress, self.localPort, self.remoteAddress, self.remotePort
      )
    }

    if (self._chunk) {
      try {
        self.send(self._chunk)
      } catch (err) {
        return self._destroy(err)
      }
      self._chunk = null
      self._debug('sent chunk from "write before connect"')

      var cb = self._cb
      self._cb = null
      cb(null)
    }

    // If `bufferedAmountLowThreshold` and 'onbufferedamountlow' are unsupported,
    // fallback to using setInterval to implement backpressure.
    if (typeof self._channel.bufferedAmountLowThreshold !== 'number') {
      self._interval = setInterval(function () { self._onInterval() }, 150)
      if (self._interval.unref) self._interval.unref()
    }

    self._debug('connect')
    self.emit('connect')
  })
}

Peer.prototype._onInterval = function () {
  if (!this._cb || !this._channel || this._channel.bufferedAmount > MAX_BUFFERED_AMOUNT) {
    return
  }
  this._onChannelBufferedAmountLow()
}

Peer.prototype._onSignalingStateChange = function () {
  var self = this
  if (self.destroyed) return
  self._debug('signalingStateChange %s', self._pc.signalingState)
  self.emit('signalingStateChange', self._pc.signalingState)
}

Peer.prototype._onIceCandidate = function (event) {
  var self = this
  if (self.destroyed) return
  if (event.candidate && self.trickle) {
    self.emit('signal', {
      candidate: {
        candidate: event.candidate.candidate,
        sdpMLineIndex: event.candidate.sdpMLineIndex,
        sdpMid: event.candidate.sdpMid
      }
    })
  } else if (!event.candidate) {
    self._iceComplete = true
    self.emit('_iceComplete')
  }
}

Peer.prototype._onChannelMessage = function (event) {
  var self = this
  if (self.destroyed) return
  var data = event.data
  if (data instanceof ArrayBuffer) data = Buffer.from(data)
  self.push(data)
}

Peer.prototype._onChannelBufferedAmountLow = function () {
  var self = this
  if (self.destroyed || !self._cb) return
  self._debug('ending backpressure: bufferedAmount %d', self._channel.bufferedAmount)
  var cb = self._cb
  self._cb = null
  cb(null)
}

Peer.prototype._onChannelOpen = function () {
  var self = this
  if (self.connected || self.destroyed) return
  self._debug('on channel open')
  self._channelReady = true
  self._maybeReady()
}

Peer.prototype._onChannelClose = function () {
  var self = this
  if (self.destroyed) return
  self._debug('on channel close')
  self._destroy()
}

Peer.prototype._onAddStream = function (event) {
  var self = this
  if (self.destroyed) return
  self._debug('on add stream')
  self.emit('stream', event.stream)
}

Peer.prototype._onTrack = function (event) {
  var self = this
  if (self.destroyed) return
  self._debug('on track')
  var id = event.streams[0].id
  if (self._previousStreams.indexOf(id) !== -1) return // Only fire one 'stream' event, even though there may be multiple tracks per stream
  self._previousStreams.push(id)
  self.emit('stream', event.streams[0])
}

Peer.prototype._debug = function () {
  var self = this
  var args = [].slice.call(arguments)
  args[0] = '[' + self._id + '] ' + args[0]
  debug.apply(null, args)
}

// Transform constraints objects into the new format (unless Chromium)
// TODO: This can be removed when Chromium supports the new format
Peer.prototype._transformConstraints = function (constraints) {
  var self = this

  if (Object.keys(constraints).length === 0) {
    return constraints
  }

  if ((constraints.mandatory || constraints.optional) && !self._isChromium) {
    // convert to new format

    // Merge mandatory and optional objects, prioritizing mandatory
    var newConstraints = Object.assign({}, constraints.optional, constraints.mandatory)

    // fix casing
    if (newConstraints.OfferToReceiveVideo !== undefined) {
      newConstraints.offerToReceiveVideo = newConstraints.OfferToReceiveVideo
      delete newConstraints['OfferToReceiveVideo']
    }

    if (newConstraints.OfferToReceiveAudio !== undefined) {
      newConstraints.offerToReceiveAudio = newConstraints.OfferToReceiveAudio
      delete newConstraints['OfferToReceiveAudio']
    }

    return newConstraints
  } else if (!constraints.mandatory && !constraints.optional && self._isChromium) {
    // convert to old format

    // fix casing
    if (constraints.offerToReceiveVideo !== undefined) {
      constraints.OfferToReceiveVideo = constraints.offerToReceiveVideo
      delete constraints['offerToReceiveVideo']
    }

    if (constraints.offerToReceiveAudio !== undefined) {
      constraints.OfferToReceiveAudio = constraints.offerToReceiveAudio
      delete constraints['offerToReceiveAudio']
    }

    return {
      mandatory: constraints // NOTE: All constraints are upgraded to mandatory
    }
  }

  return constraints
}

function noop () {}

}).call(this,require("buffer").Buffer)
},{"buffer":3,"debug":10,"get-browser-rtc":12,"inherits":14,"randombytes":18,"readable-stream":27}],31:[function(require,module,exports){
'use strict';

var Buffer = require('safe-buffer').Buffer;

var isEncoding = Buffer.isEncoding || function (encoding) {
  encoding = '' + encoding;
  switch (encoding && encoding.toLowerCase()) {
    case 'hex':case 'utf8':case 'utf-8':case 'ascii':case 'binary':case 'base64':case 'ucs2':case 'ucs-2':case 'utf16le':case 'utf-16le':case 'raw':
      return true;
    default:
      return false;
  }
};

function _normalizeEncoding(enc) {
  if (!enc) return 'utf8';
  var retried;
  while (true) {
    switch (enc) {
      case 'utf8':
      case 'utf-8':
        return 'utf8';
      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return 'utf16le';
      case 'latin1':
      case 'binary':
        return 'latin1';
      case 'base64':
      case 'ascii':
      case 'hex':
        return enc;
      default:
        if (retried) return; // undefined
        enc = ('' + enc).toLowerCase();
        retried = true;
    }
  }
};

// Do not cache `Buffer.isEncoding` when checking encoding names as some
// modules monkey-patch it to support additional encodings
function normalizeEncoding(enc) {
  var nenc = _normalizeEncoding(enc);
  if (typeof nenc !== 'string' && (Buffer.isEncoding === isEncoding || !isEncoding(enc))) throw new Error('Unknown encoding: ' + enc);
  return nenc || enc;
}

// StringDecoder provides an interface for efficiently splitting a series of
// buffers into a series of JS strings without breaking apart multi-byte
// characters.
exports.StringDecoder = StringDecoder;
function StringDecoder(encoding) {
  this.encoding = normalizeEncoding(encoding);
  var nb;
  switch (this.encoding) {
    case 'utf16le':
      this.text = utf16Text;
      this.end = utf16End;
      nb = 4;
      break;
    case 'utf8':
      this.fillLast = utf8FillLast;
      nb = 4;
      break;
    case 'base64':
      this.text = base64Text;
      this.end = base64End;
      nb = 3;
      break;
    default:
      this.write = simpleWrite;
      this.end = simpleEnd;
      return;
  }
  this.lastNeed = 0;
  this.lastTotal = 0;
  this.lastChar = Buffer.allocUnsafe(nb);
}

StringDecoder.prototype.write = function (buf) {
  if (buf.length === 0) return '';
  var r;
  var i;
  if (this.lastNeed) {
    r = this.fillLast(buf);
    if (r === undefined) return '';
    i = this.lastNeed;
    this.lastNeed = 0;
  } else {
    i = 0;
  }
  if (i < buf.length) return r ? r + this.text(buf, i) : this.text(buf, i);
  return r || '';
};

StringDecoder.prototype.end = utf8End;

// Returns only complete characters in a Buffer
StringDecoder.prototype.text = utf8Text;

// Attempts to complete a partial non-UTF-8 character using bytes from a Buffer
StringDecoder.prototype.fillLast = function (buf) {
  if (this.lastNeed <= buf.length) {
    buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, this.lastNeed);
    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
  }
  buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, buf.length);
  this.lastNeed -= buf.length;
};

// Checks the type of a UTF-8 byte, whether it's ASCII, a leading byte, or a
// continuation byte.
function utf8CheckByte(byte) {
  if (byte <= 0x7F) return 0;else if (byte >> 5 === 0x06) return 2;else if (byte >> 4 === 0x0E) return 3;else if (byte >> 3 === 0x1E) return 4;
  return -1;
}

// Checks at most 3 bytes at the end of a Buffer in order to detect an
// incomplete multi-byte UTF-8 character. The total number of bytes (2, 3, or 4)
// needed to complete the UTF-8 character (if applicable) are returned.
function utf8CheckIncomplete(self, buf, i) {
  var j = buf.length - 1;
  if (j < i) return 0;
  var nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) self.lastNeed = nb - 1;
    return nb;
  }
  if (--j < i) return 0;
  nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) self.lastNeed = nb - 2;
    return nb;
  }
  if (--j < i) return 0;
  nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) {
      if (nb === 2) nb = 0;else self.lastNeed = nb - 3;
    }
    return nb;
  }
  return 0;
}

// Validates as many continuation bytes for a multi-byte UTF-8 character as
// needed or are available. If we see a non-continuation byte where we expect
// one, we "replace" the validated continuation bytes we've seen so far with
// UTF-8 replacement characters ('\ufffd'), to match v8's UTF-8 decoding
// behavior. The continuation byte check is included three times in the case
// where all of the continuation bytes for a character exist in the same buffer.
// It is also done this way as a slight performance increase instead of using a
// loop.
function utf8CheckExtraBytes(self, buf, p) {
  if ((buf[0] & 0xC0) !== 0x80) {
    self.lastNeed = 0;
    return '\ufffd'.repeat(p);
  }
  if (self.lastNeed > 1 && buf.length > 1) {
    if ((buf[1] & 0xC0) !== 0x80) {
      self.lastNeed = 1;
      return '\ufffd'.repeat(p + 1);
    }
    if (self.lastNeed > 2 && buf.length > 2) {
      if ((buf[2] & 0xC0) !== 0x80) {
        self.lastNeed = 2;
        return '\ufffd'.repeat(p + 2);
      }
    }
  }
}

// Attempts to complete a multi-byte UTF-8 character using bytes from a Buffer.
function utf8FillLast(buf) {
  var p = this.lastTotal - this.lastNeed;
  var r = utf8CheckExtraBytes(this, buf, p);
  if (r !== undefined) return r;
  if (this.lastNeed <= buf.length) {
    buf.copy(this.lastChar, p, 0, this.lastNeed);
    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
  }
  buf.copy(this.lastChar, p, 0, buf.length);
  this.lastNeed -= buf.length;
}

// Returns all complete UTF-8 characters in a Buffer. If the Buffer ended on a
// partial character, the character's bytes are buffered until the required
// number of bytes are available.
function utf8Text(buf, i) {
  var total = utf8CheckIncomplete(this, buf, i);
  if (!this.lastNeed) return buf.toString('utf8', i);
  this.lastTotal = total;
  var end = buf.length - (total - this.lastNeed);
  buf.copy(this.lastChar, 0, end);
  return buf.toString('utf8', i, end);
}

// For UTF-8, a replacement character for each buffered byte of a (partial)
// character needs to be added to the output.
function utf8End(buf) {
  var r = buf && buf.length ? this.write(buf) : '';
  if (this.lastNeed) return r + '\ufffd'.repeat(this.lastTotal - this.lastNeed);
  return r;
}

// UTF-16LE typically needs two bytes per character, but even if we have an even
// number of bytes available, we need to check if we end on a leading/high
// surrogate. In that case, we need to wait for the next two bytes in order to
// decode the last character properly.
function utf16Text(buf, i) {
  if ((buf.length - i) % 2 === 0) {
    var r = buf.toString('utf16le', i);
    if (r) {
      var c = r.charCodeAt(r.length - 1);
      if (c >= 0xD800 && c <= 0xDBFF) {
        this.lastNeed = 2;
        this.lastTotal = 4;
        this.lastChar[0] = buf[buf.length - 2];
        this.lastChar[1] = buf[buf.length - 1];
        return r.slice(0, -1);
      }
    }
    return r;
  }
  this.lastNeed = 1;
  this.lastTotal = 2;
  this.lastChar[0] = buf[buf.length - 1];
  return buf.toString('utf16le', i, buf.length - 1);
}

// For UTF-16LE we do not explicitly append special replacement characters if we
// end on a partial character, we simply let v8 handle that.
function utf16End(buf) {
  var r = buf && buf.length ? this.write(buf) : '';
  if (this.lastNeed) {
    var end = this.lastTotal - this.lastNeed;
    return r + this.lastChar.toString('utf16le', 0, end);
  }
  return r;
}

function base64Text(buf, i) {
  var n = (buf.length - i) % 3;
  if (n === 0) return buf.toString('base64', i);
  this.lastNeed = 3 - n;
  this.lastTotal = 3;
  if (n === 1) {
    this.lastChar[0] = buf[buf.length - 1];
  } else {
    this.lastChar[0] = buf[buf.length - 2];
    this.lastChar[1] = buf[buf.length - 1];
  }
  return buf.toString('base64', i, buf.length - n);
}

function base64End(buf) {
  var r = buf && buf.length ? this.write(buf) : '';
  if (this.lastNeed) return r + this.lastChar.toString('base64', 0, 3 - this.lastNeed);
  return r;
}

// Pass bytes on through for single-byte encodings (e.g. ascii, latin1, hex)
function simpleWrite(buf) {
  return buf.toString(this.encoding);
}

function simpleEnd(buf) {
  return buf && buf.length ? this.write(buf) : '';
}
},{"safe-buffer":32}],32:[function(require,module,exports){
arguments[4][26][0].apply(exports,arguments)
},{"buffer":3,"dup":26}],33:[function(require,module,exports){
(function (global){

/**
 * Module exports.
 */

module.exports = deprecate;

/**
 * Mark that a method should not be used.
 * Returns a modified function which warns once by default.
 *
 * If `localStorage.noDeprecation = true` is set, then it is a no-op.
 *
 * If `localStorage.throwDeprecation = true` is set, then deprecated functions
 * will throw an Error when invoked.
 *
 * If `localStorage.traceDeprecation = true` is set, then deprecated functions
 * will invoke `console.trace()` instead of `console.error()`.
 *
 * @param {Function} fn - the function to deprecate
 * @param {String} msg - the string to print to the console when `fn` is invoked
 * @returns {Function} a new "deprecated" version of `fn`
 * @api public
 */

function deprecate (fn, msg) {
  if (config('noDeprecation')) {
    return fn;
  }

  var warned = false;
  function deprecated() {
    if (!warned) {
      if (config('throwDeprecation')) {
        throw new Error(msg);
      } else if (config('traceDeprecation')) {
        console.trace(msg);
      } else {
        console.warn(msg);
      }
      warned = true;
    }
    return fn.apply(this, arguments);
  }

  return deprecated;
}

/**
 * Checks `localStorage` for boolean values for the given `name`.
 *
 * @param {String} name
 * @returns {Boolean}
 * @api private
 */

function config (name) {
  // accessing global.localStorage can trigger a DOMException in sandboxed iframes
  try {
    if (!global.localStorage) return false;
  } catch (_) {
    return false;
  }
  var val = global.localStorage[name];
  if (null == val) return false;
  return String(val).toLowerCase() === 'true';
}

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],34:[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.
(function() {
  // Utils.
  var logging = require('./utils').log;
  var browserDetails = require('./utils').browserDetails;
  // Export to the adapter global object visible in the browser.
  module.exports.browserDetails = browserDetails;
  module.exports.extractVersion = require('./utils').extractVersion;
  module.exports.disableLog = require('./utils').disableLog;

  // 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 'opera': // fallthrough as it uses chrome shims
    case 'chrome':
      if (!chromeShim || !chromeShim.shimPeerConnection) {
        logging('Chrome shim is not included in this adapter release.');
        return;
      }
      logging('adapter.js shimming chrome.');
      // Export to the adapter global object visible in the browser.
      module.exports.browserShim = chromeShim;

      chromeShim.shimGetUserMedia();
      chromeShim.shimMediaStream();
      chromeShim.shimSourceObject();
      chromeShim.shimPeerConnection();
      chromeShim.shimOnTrack();
      break;
    case 'firefox':
      if (!firefoxShim || !firefoxShim.shimPeerConnection) {
        logging('Firefox shim is not included in this adapter release.');
        return;
      }
      logging('adapter.js shimming firefox.');
      // Export to the adapter global object visible in the browser.
      module.exports.browserShim = firefoxShim;

      firefoxShim.shimGetUserMedia();
      firefoxShim.shimSourceObject();
      firefoxShim.shimPeerConnection();
      firefoxShim.shimOnTrack();
      break;
    case 'edge':
      if (!edgeShim || !edgeShim.shimPeerConnection) {
        logging('MS edge shim is not included in this adapter release.');
        return;
      }
      logging('adapter.js shimming edge.');
      // Export to the adapter global object visible in the browser.
      module.exports.browserShim = edgeShim;

      edgeShim.shimGetUserMedia();
      edgeShim.shimPeerConnection();
      break;
    case 'safari':
      if (!safariShim) {
        logging('Safari shim is not included in this adapter release.');
        return;
      }
      logging('adapter.js shimming safari.');
      // Export to the adapter global object visible in the browser.
      module.exports.browserShim = safariShim;

      safariShim.shimGetUserMedia();
      break;
    default:
      logging('Unsupported browser!');
  }
})();

},{"./chrome/chrome_shim":35,"./edge/edge_shim":37,"./firefox/firefox_shim":39,"./safari/safari_shim":41,"./utils":42}],35:[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 logging = require('../utils.js').log;
var browserDetails = require('../utils.js').browserDetails;

var chromeShim = {
  shimMediaStream: function() {
    window.MediaStream = window.MediaStream || window.webkitMediaStream;
  },

  shimOnTrack: function() {
    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 event = new Event('track');
              event.track = te.track;
              event.receiver = {track: te.track};
              event.streams = [e.stream];
              self.dispatchEvent(event);
            });
            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() {
    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;
            }
            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() {
    // The RTCPeerConnection object.
    window.RTCPeerConnection = function(pcConfig, pcConstraints) {
      // Translate iceTransportPolicy to iceTransports,
      // see https://code.google.com/p/webrtc/issues/detail?id=4869
      logging('PeerConnection');
      if (pcConfig && pcConfig.iceTransportPolicy) {
        pcConfig.iceTransports = pcConfig.iceTransportPolicy;
      }

      var pc = new webkitRTCPeerConnection(pcConfig, pcConstraints);
      var origGetStats = pc.getStats.bind(pc);
      pc.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(selector, successCallback);
        }

        var fixChromeStats_ = function(response) {
          var standardReport = {};
          var reports = response.result();
          reports.forEach(function(report) {
            var standardStats = {
              id: report.id,
              timestamp: report.timestamp,
              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, legacyStats) {
          var map = new Map(Object.keys(stats).map(function(key) {
            return[key, stats[key]];
          }));
          legacyStats = legacyStats || stats;
          Object.keys(legacyStats).forEach(function(key) {
            map[key] = legacyStats[key];
          });
          return map;
        };

        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) {
          if (args.length === 1 && typeof selector === 'object') {
            origGetStats.apply(self, [
              function(response) {
                resolve(makeMapStats(fixChromeStats_(response)));
              }, reject]);
          } else {
            // Preserve legacy chrome stats only on legacy access of stats obj
            origGetStats.apply(self, [
              function(response) {
                resolve(makeMapStats(fixChromeStats_(response),
                    response.result()));
              }, reject]);
          }
        }).then(successCallback, errorCallback);
      };

      return pc;
    };
    window.RTCPeerConnection.prototype = webkitRTCPeerConnection.prototype;

    // wrap static methods. Currently just generateCertificate.
    if (webkitRTCPeerConnection.generateCertificate) {
      Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
        get: function() {
          return webkitRTCPeerConnection.generateCertificate;
        }
      });
    }

    ['createOffer', 'createAnswer'].forEach(function(method) {
      var nativeMethod = webkitRTCPeerConnection.prototype[method];
      webkitRTCPeerConnection.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);
      };
    });

    // add promise support -- natively available in Chrome 51
    if (browserDetails.version < 51) {
      ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
          .forEach(function(method) {
            var nativeMethod = webkitRTCPeerConnection.prototype[method];
            webkitRTCPeerConnection.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]);
                }
              });
            };
          });
    }

    // shim implicit creation of RTCSessionDescription/RTCIceCandidate
    ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
        .forEach(function(method) {
          var nativeMethod = webkitRTCPeerConnection.prototype[method];
          webkitRTCPeerConnection.prototype[method] = function() {
            arguments[0] = new ((method === 'addIceCandidate') ?
                RTCIceCandidate : RTCSessionDescription)(arguments[0]);
            return nativeMethod.apply(this, arguments);
          };
        });

    // support for addIceCandidate(null or undefined)
    var nativeAddIceCandidate =
        RTCPeerConnection.prototype.addIceCandidate;
    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,
  shimSourceObject: chromeShim.shimSourceObject,
  shimPeerConnection: chromeShim.shimPeerConnection,
  shimGetUserMedia: require('./getusermedia')
};

},{"../utils.js":42,"./getusermedia":36}],36:[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 logging = require('../utils.js').log;

// Expose public methods.
module.exports = function() {
  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 && constraints.audio) {
      constraints.audio = constraintsToChrome_(constraints.audio);
    }
    if (constraints && typeof constraints.video === 'object') {
      // Shim facingMode for mobile, where it defaults to "user".
      var face = constraints.video.facingMode;
      face = face && ((typeof face === 'object') ? face : {ideal: face});

      if ((face && (face.exact === 'user' || face.exact === 'environment' ||
                    face.ideal === 'user' || face.ideal === 'environment')) &&
          !(navigator.mediaDevices.getSupportedConstraints &&
            navigator.mediaDevices.getSupportedConstraints().facingMode)) {
        delete constraints.video.facingMode;
        if (face.exact === 'environment' || face.ideal === 'environment') {
          // Look for "back" in label, or use last cam (typically back cam).
          return navigator.mediaDevices.enumerateDevices()
          .then(function(devices) {
            devices = devices.filter(function(d) {
              return d.kind === 'videoinput';
            });
            var back = devices.find(function(d) {
              return d.label.toLowerCase().indexOf('back') !== -1;
            }) || (devices.length && devices[devices.length - 1]);
            if (back) {
              constraints.video.deviceId = face.exact ? {exact: back.deviceId} :
                                                        {ideal: back.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',
        ConstraintNotSatisfiedError: 'OverconstrainedError'
      }[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 MediaStreamTrack.getSources(function(devices) {
            resolve(devices.map(function(device) {
              return {label: device.label,
                      kind: kinds[device.kind],
                      deviceId: device.id,
                      groupId: ''};
            }));
          });
        });
      }
    };
  }

  // 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":42}],37:[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 SDPUtils = require('sdp');
var browserDetails = require('../utils').browserDetails;

var edgeShim = {
  shimPeerConnection: function() {
    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.
      var origMSTEnabled = Object.getOwnPropertyDescriptor(
          MediaStreamTrack.prototype, 'enabled');
      Object.defineProperty(MediaStreamTrack.prototype, 'enabled', {
        set: function(value) {
          origMSTEnabled.set.call(this, value);
          var ev = new Event('enabled');
          ev.enabled = value;
          this.dispatchEvent(ev);
        }
      });
    }

    window.RTCPeerConnection = function(config) {
      var self = this;

      var _eventTarget = document.createDocumentFragment();
      ['addEventListener', 'removeEventListener', 'dispatchEvent']
          .forEach(function(method) {
            self[method] = _eventTarget[method].bind(_eventTarget);
          });

      this.onicecandidate = null;
      this.onaddstream = null;
      this.ontrack = null;
      this.onremovestream = null;
      this.onsignalingstatechange = null;
      this.oniceconnectionstatechange = null;
      this.onnegotiationneeded = null;
      this.ondatachannel = null;

      this.localStreams = [];
      this.remoteStreams = [];
      this.getLocalStreams = function() {
        return self.localStreams;
      };
      this.getRemoteStreams = function() {
        return self.remoteStreams;
      };

      this.localDescription = new RTCSessionDescription({
        type: '',
        sdp: ''
      });
      this.remoteDescription = new 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;
          case 'none':
            // FIXME: remove once implementation and spec have added this.
            throw new TypeError('iceTransportPolicy "none" not supported');
          default:
            // don't set iceTransportPolicy.
            break;
        }
      }
      this.usingBundle = config && config.bundlePolicy === 'max-bundle';

      if (config && config.iceServers) {
        // Edge does not like
        // 1) stun:
        // 2) turn: that does not have all of turn:host:port?transport=udp
        // 3) turn: with ipv6 addresses
        var iceServers = JSON.parse(JSON.stringify(config.iceServers));
        this.iceOptions.iceServers = iceServers.filter(function(server) {
          if (server && server.urls) {
            var urls = server.urls;
            if (typeof urls === 'string') {
              urls = [urls];
            }
            urls = urls.filter(function(url) {
              return (url.indexOf('turn:') === 0 &&
                  url.indexOf('transport=udp') !== -1 &&
                  url.indexOf('turn:[') === -1) ||
                  (url.indexOf('stun:') === 0 &&
                    browserDetails.version >= 14393);
            })[0];
            return !!urls;
          }
          return false;
        });
      }
      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 = [];
    };

    window.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 if (event.candidate.candidate.indexOf('typ endOfCandidates')
            === -1) {
          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.iceGatheringState = 'complete';
          }
        }
      });
      this._localIceCandidatesBuffer = [];
    };

    window.RTCPeerConnection.prototype.getConfiguration = function() {
      return this._config;
    };

    window.RTCPeerConnection.prototype.addStream = function(stream) {
      // Clone is necessary for local demos mostly, attaching directly
      // to two different senders does not work (build 10547).
      var clonedStream = stream.clone();
      stream.getTracks().forEach(function(track, idx) {
        var clonedTrack = clonedStream.getTracks()[idx];
        track.addEventListener('enabled', function(event) {
          clonedTrack.enabled = event.enabled;
        });
      });
      this.localStreams.push(clonedStream);
      this._maybeFireNegotiationNeeded();
    };

    window.RTCPeerConnection.prototype.removeStream = function(stream) {
      var idx = this.localStreams.indexOf(stream);
      if (idx > -1) {
        this.localStreams.splice(idx, 1);
        this._maybeFireNegotiationNeeded();
      }
    };

    window.RTCPeerConnection.prototype.getSenders = function() {
      return this.transceivers.filter(function(transceiver) {
        return !!transceiver.rtpSender;
      })
      .map(function(transceiver) {
        return transceiver.rtpSender;
      });
    };

    window.RTCPeerConnection.prototype.getReceivers = function() {
      return this.transceivers.filter(function(transceiver) {
        return !!transceiver.rtpReceiver;
      })
      .map(function(transceiver) {
        return transceiver.rtpReceiver;
      });
    };

    // Determines the intersection of local and remote capabilities.
    window.RTCPeerConnection.prototype._getCommonCapabilities =
        function(localCapabilities, remoteCapabilities) {
          var commonCapabilities = {
            codecs: [],
            headerExtensions: [],
            fecMechanisms: []
          };
          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) {
                // 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;
        };

    // Create ICE gatherer, ICE transport and DTLS transport.
    window.RTCPeerConnection.prototype._createIceAndDtlsTransports =
        function(mid, sdpMLineIndex) {
          var self = this;
          var iceGatherer = new RTCIceGatherer(self.iceOptions);
          var iceTransport = new RTCIceTransport(iceGatherer);
          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 RTCIceCandidateComplete‥
            if (end) {
              // polyfill since RTCIceGatherer.state is not implemented in
              // Edge 10547 yet.
              if (iceGatherer.state === undefined) {
                iceGatherer.state = 'completed';
              }

              // Emit a candidate with type endOfCandidates to make the samples
              // work. Edge requires addIceCandidate with this empty candidate
              // to start checking. The real solution is to signal
              // end-of-candidates to the other side when getting the null
              // candidate but some apps (like the samples) don't do that.
              event.candidate.candidate =
                  'candidate:1 1 udp 1 0.0.0.0 9 typ endOfCandidates';
            } else {
              // RTCIceCandidate doesn't have a component, needs to be added
              cand.component = iceTransport.component === 'RTCP' ? 2 : 1;
              event.candidate.candidate = SDPUtils.writeCandidate(cand);
            }

            // update local description.
            var sections = SDPUtils.splitSections(self.localDescription.sdp);
            if (event.candidate.candidate.indexOf('typ endOfCandidates')
                === -1) {
              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 complete = self.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':
                self._localIceCandidatesBuffer.push(event);
                if (end && complete) {
                  self._localIceCandidatesBuffer.push(
                      new Event('icecandidate'));
                }
                break;
              case 'gathering':
                self._emitBufferedCandidates();
                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';
                }
                break;
              case 'complete':
                // should not happen... currently!
                break;
              default: // no-op.
                break;
            }
          };
          iceTransport.onicestatechange = function() {
            self._updateConnectionState();
          };

          var dtlsTransport = new RTCDtlsTransport(iceTransport);
          dtlsTransport.ondtlsstatechange = function() {
            self._updateConnectionState();
          };
          dtlsTransport.onerror = function() {
            // onerror does not set state to failed by itself.
            dtlsTransport.state = 'failed';
            self._updateConnectionState();
          };

          return {
            iceGatherer: iceGatherer,
            iceTransport: iceTransport,
            dtlsTransport: dtlsTransport
          };
        };

    // Start the RTP Sender and Receiver for a transceiver.
    window.RTCPeerConnection.prototype._transceive = function(transceiver,
        send, recv) {
      var params = this._getCommonCapabilities(transceiver.localCapabilities,
          transceiver.remoteCapabilities);
      if (send && transceiver.rtpSender) {
        params.encodings = transceiver.sendEncodingParameters;
        params.rtcp = {
          cname: SDPUtils.localCName
        };
        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) {
          transceiver.recvEncodingParameters.forEach(function(p) {
            delete p.rtx;
          });
        }
        params.encodings = transceiver.recvEncodingParameters;
        params.rtcp = {
          cname: transceiver.cname
        };
        if (transceiver.sendEncodingParameters.length) {
          params.rtcp.ssrc = transceiver.sendEncodingParameters[0].ssrc;
        }
        transceiver.rtpReceiver.receive(params);
      }
    };

    window.RTCPeerConnection.prototype.setLocalDescription =
        function(description) {
          var self = this;
          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 = mediaSection.split('\n', 1)[0]
                  .split(' ', 2)[1] === '0';

              if (!rejected && !transceiver.isDatachannel) {
                var remoteIceParameters = SDPUtils.getIceParameters(
                    mediaSection, sessionpart);
                if (isIceLite) {
                  var cands = SDPUtils.matchPrefix(mediaSection, 'a=candidate:')
                  .map(function(cand) {
                    return SDPUtils.parseCandidate(cand);
                  })
                  .filter(function(cand) {
                    return cand.component === '1';
                  });
                  // ice-lite only includes host candidates in the SDP so we can
                  // use setRemoteCandidates (which implies an
                  // RTCIceCandidateComplete)
                  if (cands.length) {
                    iceTransport.setRemoteCandidates(cands);
                  }
                }
                var 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 = self._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._emitBufferedCandidates();
            }, 0);
          }
          var p = Promise.resolve();
          p.then(function() {
            if (!hasCallback) {
              if (self.iceGatheringState === 'new') {
                self.iceGatheringState = 'gathering';
              }
              // Usually candidates will be emitted earlier.
              window.setTimeout(self._emitBufferedCandidates.bind(self), 500);
            }
          });
          return p;
        };

    window.RTCPeerConnection.prototype.setRemoteDescription =
        function(description) {
          var self = this;
          var stream = new MediaStream();
          var receiverList = [];
          var sections = SDPUtils.splitSections(description.sdp);
          var sessionpart = sections.shift();
          var isIceLite = SDPUtils.matchPrefix(sessionpart,
              'a=ice-lite').length > 0;
          this.usingBundle = SDPUtils.matchPrefix(sessionpart,
              'a=group:BUNDLE ').length > 0;
          sections.forEach(function(mediaSection, sdpMLineIndex) {
            var lines = SDPUtils.splitLines(mediaSection);
            var mline = lines[0].substr(2).split(' ');
            var kind = mline[0];
            var rejected = mline[1] === '0';
            var direction = SDPUtils.getDirection(mediaSection, sessionpart);

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

            // Reject datachannels which are not implemented yet.
            if (kind === 'application' && mline[2] === 'DTLS/SCTP') {
              self.transceivers[sdpMLineIndex] = {
                mid: mid,
                isDatachannel: true
              };
              return;
            }

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

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

            var cname;
            // Gets the first SSRC. Note that with RTX there might be multiple
            // SSRCs.
            var remoteSsrc = SDPUtils.matchPrefix(mediaSection, 'a=ssrc:')
                .map(function(line) {
                  return SDPUtils.parseSsrcMedia(line);
                })
                .filter(function(obj) {
                  return obj.attribute === 'cname';
                })[0];
            if (remoteSsrc) {
              cname = remoteSsrc.value;
            }

            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';
                });
            if (description.type === 'offer' && !rejected) {
              var transports = self.usingBundle && sdpMLineIndex > 0 ? {
                iceGatherer: self.transceivers[0].iceGatherer,
                iceTransport: self.transceivers[0].iceTransport,
                dtlsTransport: self.transceivers[0].dtlsTransport
              } : self._createIceAndDtlsTransports(mid, sdpMLineIndex);

              if (isComplete) {
                transports.iceTransport.setRemoteCandidates(cands);
              }

              localCapabilities = RTCRtpReceiver.getCapabilities(kind);

              // filter RTX until additional stuff needed for RTX is implemented
              // in adapter.js
              localCapabilities.codecs = localCapabilities.codecs.filter(
                  function(codec) {
                    return codec.name !== 'rtx';
                  });

              sendEncodingParameters = [{
                ssrc: (2 * sdpMLineIndex + 2) * 1001
              }];

              rtpReceiver = new RTCRtpReceiver(transports.dtlsTransport, kind);

              track = rtpReceiver.track;
              receiverList.push([track, rtpReceiver]);
              // FIXME: not correct when there are multiple streams but that is
              // not currently supported in this shim.
              stream.addTrack(track);

              // FIXME: look at direction.
              if (self.localStreams.length > 0 &&
                  self.localStreams[0].getTracks().length >= sdpMLineIndex) {
                var localTrack;
                if (kind === 'audio') {
                  localTrack = self.localStreams[0].getAudioTracks()[0];
                } else if (kind === 'video') {
                  localTrack = self.localStreams[0].getVideoTracks()[0];
                }
                if (localTrack) {
                  rtpSender = new RTCRtpSender(localTrack,
                      transports.dtlsTransport);
                }
              }

              self.transceivers[sdpMLineIndex] = {
                iceGatherer: transports.iceGatherer,
                iceTransport: transports.iceTransport,
                dtlsTransport: transports.dtlsTransport,
                localCapabilities: localCapabilities,
                remoteCapabilities: remoteCapabilities,
                rtpSender: rtpSender,
                rtpReceiver: rtpReceiver,
                kind: kind,
                mid: mid,
                cname: cname,
                sendEncodingParameters: sendEncodingParameters,
                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;
              rtpSender = transceiver.rtpSender;
              rtpReceiver = transceiver.rtpReceiver;
              sendEncodingParameters = transceiver.sendEncodingParameters;
              localCapabilities = transceiver.localCapabilities;

              self.transceivers[sdpMLineIndex].recvEncodingParameters =
                  recvEncodingParameters;
              self.transceivers[sdpMLineIndex].remoteCapabilities =
                  remoteCapabilities;
              self.transceivers[sdpMLineIndex].cname = cname;

              if ((isIceLite || isComplete) && cands.length) {
                iceTransport.setRemoteCandidates(cands);
              }
              if (!self.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;
                receiverList.push([track, rtpReceiver]);
                stream.addTrack(track);
              } 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 +
                  '"');
          }
          if (stream.getTracks().length) {
            self.remoteStreams.push(stream);
            window.setTimeout(function() {
              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];
                var trackEvent = new Event('track');
                trackEvent.track = track;
                trackEvent.receiver = receiver;
                trackEvent.streams = [stream];
                self.dispatchEvent(event);
                if (self.ontrack !== null) {
                  window.setTimeout(function() {
                    self.ontrack(trackEvent);
                  }, 0);
                }
              });
            }, 0);
          }
          if (arguments.length > 1 && typeof arguments[1] === 'function') {
            window.setTimeout(arguments[1], 0);
          }
          return Promise.resolve();
        };

    window.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.
    window.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.
    window.RTCPeerConnection.prototype._maybeFireNegotiationNeeded =
        function() {
          // Fire away (for now).
          var event = new Event('negotiationneeded');
          this.dispatchEvent(event);
          if (this.onnegotiationneeded !== null) {
            this.onnegotiationneeded(event);
          }
        };

    // Update the connection state.
    window.RTCPeerConnection.prototype._updateConnectionState = function() {
      var self = this;
      var newState;
      var states = {
        'new': 0,
        closed: 0,
        connecting: 0,
        checking: 0,
        connected: 0,
        completed: 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);
        }
      }
    };

    window.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 tracks = [];
      var numAudioTracks = 0;
      var numVideoTracks = 0;
      // Default to sendrecv.
      if (this.localStreams.length) {
        numAudioTracks = this.localStreams[0].getAudioTracks().length;
        numVideoTracks = this.localStreams[0].getVideoTracks().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) {
          numAudioTracks = offerOptions.offerToReceiveAudio;
        }
        if (offerOptions.offerToReceiveVideo !== undefined) {
          numVideoTracks = offerOptions.offerToReceiveVideo;
        }
      }
      if (this.localStreams.length) {
        // Push local streams.
        this.localStreams[0].getTracks().forEach(function(track) {
          tracks.push({
            kind: track.kind,
            track: track,
            wantReceive: track.kind === 'audio' ?
                numAudioTracks > 0 : numVideoTracks > 0
          });
          if (track.kind === 'audio') {
            numAudioTracks--;
          } else if (track.kind === 'video') {
            numVideoTracks--;
          }
        });
      }
      // Create M-lines for recvonly streams.
      while (numAudioTracks > 0 || numVideoTracks > 0) {
        if (numAudioTracks > 0) {
          tracks.push({
            kind: 'audio',
            wantReceive: true
          });
          numAudioTracks--;
        }
        if (numVideoTracks > 0) {
          tracks.push({
            kind: 'video',
            wantReceive: true
          });
          numVideoTracks--;
        }
      }

      var sdp = SDPUtils.writeSessionBoilerplate();
      var transceivers = [];
      tracks.forEach(function(mline, sdpMLineIndex) {
        // For each track, create an ice gatherer, ice transport,
        // dtls transport, potentially rtpsender and rtpreceiver.
        var track = mline.track;
        var kind = mline.kind;
        var mid = SDPUtils.generateIdentifier();

        var transports = self.usingBundle && sdpMLineIndex > 0 ? {
          iceGatherer: transceivers[0].iceGatherer,
          iceTransport: transceivers[0].iceTransport,
          dtlsTransport: transceivers[0].dtlsTransport
        } : self._createIceAndDtlsTransports(mid, sdpMLineIndex);

        var localCapabilities = RTCRtpSender.getCapabilities(kind);
        // filter RTX until additional stuff needed for RTX is implemented
        // in adapter.js
        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';
          }
        });

        var rtpSender;
        var rtpReceiver;

        // generate an ssrc now, to be used later in rtpSender.send
        var sendEncodingParameters = [{
          ssrc: (2 * sdpMLineIndex + 1) * 1001
        }];
        if (track) {
          rtpSender = new RTCRtpSender(track, transports.dtlsTransport);
        }

        if (mline.wantReceive) {
          rtpReceiver = new RTCRtpReceiver(transports.dtlsTransport, kind);
        }

        transceivers[sdpMLineIndex] = {
          iceGatherer: transports.iceGatherer,
          iceTransport: transports.iceTransport,
          dtlsTransport: transports.dtlsTransport,
          localCapabilities: localCapabilities,
          remoteCapabilities: null,
          rtpSender: rtpSender,
          rtpReceiver: rtpReceiver,
          kind: kind,
          mid: mid,
          sendEncodingParameters: sendEncodingParameters,
          recvEncodingParameters: null
        };
      });
      if (this.usingBundle) {
        sdp += 'a=group:BUNDLE ' + transceivers.map(function(t) {
          return t.mid;
        }).join(' ') + '\r\n';
      }
      tracks.forEach(function(mline, sdpMLineIndex) {
        var transceiver = transceivers[sdpMLineIndex];
        sdp += SDPUtils.writeMediaSection(transceiver,
            transceiver.localCapabilities, 'offer', self.localStreams[0]);
      });

      this._pendingOffer = transceivers;
      var desc = new RTCSessionDescription({
        type: 'offer',
        sdp: sdp
      });
      if (arguments.length && typeof arguments[0] === 'function') {
        window.setTimeout(arguments[0], 0, desc);
      }
      return Promise.resolve(desc);
    };

    window.RTCPeerConnection.prototype.createAnswer = function() {
      var self = this;

      var sdp = SDPUtils.writeSessionBoilerplate();
      if (this.usingBundle) {
        sdp += 'a=group:BUNDLE ' + this.transceivers.map(function(t) {
          return t.mid;
        }).join(' ') + '\r\n';
      }
      this.transceivers.forEach(function(transceiver) {
        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;
        }
        // Calculate intersection of capabilities.
        var commonCapabilities = self._getCommonCapabilities(
            transceiver.localCapabilities,
            transceiver.remoteCapabilities);

        sdp += SDPUtils.writeMediaSection(transceiver, commonCapabilities,
            'answer', self.localStreams[0]);
      });

      var desc = new RTCSessionDescription({
        type: 'answer',
        sdp: sdp
      });
      if (arguments.length && typeof arguments[0] === 'function') {
        window.setTimeout(arguments[0], 0, desc);
      }
      return Promise.resolve(desc);
    };

    window.RTCPeerConnection.prototype.addIceCandidate = function(candidate) {
      if (!candidate) {
        this.transceivers.forEach(function(transceiver) {
          transceiver.iceTransport.addRemoteCandidate({});
        });
      } 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;
          }
          // Ignore RTCP candidates, we assume RTCP-MUX.
          if (cand.component !== '1') {
            return;
          }
          // A dirty hack to make samples work.
          if (cand.type === 'endOfCandidates') {
            cand = {};
          }
          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();
    };

    window.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];
      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) {
              results.set(id, result[id]);
              results[id] = result[id];
            });
          });
          if (cb) {
            window.setTimeout(cb, 0, results);
          }
          resolve(results);
        });
      });
    };
  }
};

// Expose public methods.
module.exports = {
  shimPeerConnection: edgeShim.shimPeerConnection,
  shimGetUserMedia: require('./getusermedia')
};

},{"../utils":42,"./getusermedia":38,"sdp":29}],38:[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() {
  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));
    });
  };
};

},{}],39:[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 browserDetails = require('../utils').browserDetails;

var firefoxShim = {
  shimOnTrack: function() {
    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() {
    // 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() {
    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 mozRTCPeerConnection(pcConfig, pcConstraints);
      };
      window.RTCPeerConnection.prototype = mozRTCPeerConnection.prototype;

      // wrap static methods. Currently just generateCertificate.
      if (mozRTCPeerConnection.generateCertificate) {
        Object.defineProperty(window.RTCPeerConnection, 'generateCertificate', {
          get: function() {
            return mozRTCPeerConnection.generateCertificate;
          }
        });
      }

      window.RTCSessionDescription = mozRTCSessionDescription;
      window.RTCIceCandidate = mozRTCIceCandidate;
    }

    // shim away need for obsolete RTCIceCandidate/RTCSessionDescription.
    ['setLocalDescription', 'setRemoteDescription', 'addIceCandidate']
        .forEach(function(method) {
          var nativeMethod = RTCPeerConnection.prototype[method];
          RTCPeerConnection.prototype[method] = function() {
            arguments[0] = new ((method === 'addIceCandidate') ?
                RTCIceCandidate : RTCSessionDescription)(arguments[0]);
            return nativeMethod.apply(this, arguments);
          };
        });

    // support for addIceCandidate(null or undefined)
    var nativeAddIceCandidate =
        RTCPeerConnection.prototype.addIceCandidate;
    RTCPeerConnection.prototype.addIceCandidate = function() {
      if (!arguments[0]) {
        if (arguments[1]) {
          arguments[1].apply(null);
        }
        return Promise.resolve();
      }
      return nativeAddIceCandidate.apply(this, arguments);
    };

    if (browserDetails.version < 48) {
      // 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 nativeGetStats = RTCPeerConnection.prototype.getStats;
      RTCPeerConnection.prototype.getStats = function(selector, onSucc, onErr) {
        return nativeGetStats.apply(this, [selector || null])
          .then(function(stats) {
            return makeMapStats(stats);
          })
          .then(onSucc, onErr);
      };
    }
  }
};

// Expose public methods.
module.exports = {
  shimOnTrack: firefoxShim.shimOnTrack,
  shimSourceObject: firefoxShim.shimSourceObject,
  shimPeerConnection: firefoxShim.shimPeerConnection,
  shimGetUserMedia: require('./getusermedia')
};

},{"../utils":42,"./getusermedia":40}],40:[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 logging = require('../utils').log;
var browserDetails = require('../utils').browserDetails;

// Expose public methods.
module.exports = function() {
  var shimError_ = function(e) {
    return {
      name: {
        SecurityError: 'NotAllowedError',
        PermissionDeniedError: '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));
      });
    };
  }
  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":42}],41:[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 safariShim = {
  // TODO: DrAlex, should be here, double check against LayoutTests
  // shimOnTrack: function() { },

  // TODO: once the back-end for the mac port is done, add.
  // TODO: check for webkitGTK+
  // shimPeerConnection: function() { },

  shimGetUserMedia: function() {
    navigator.getUserMedia = navigator.webkitGetUserMedia;
  }
};

// Expose public methods.
module.exports = {
  shimGetUserMedia: safariShim.shimGetUserMedia
  // TODO
  // shimOnTrack: safariShim.shimOnTrack,
  // shimPeerConnection: safariShim.shimPeerConnection
};

},{}],42:[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;

// 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';
  },

  log: function() {
    if (typeof window === 'object') {
      if (logDisabled_) {
        return;
      }
      if (typeof console !== 'undefined' && typeof console.log === 'function') {
        console.log.apply(console, arguments);
      }
    }
  },

  /**
   * 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() {
    // 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\/([0-9]+)\./, 1);

    // all webkit-based browsers
    } 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)\/([0-9]+)\./, 2);

      // Safari or unknown webkit-based
      // for the time being Safari has support for MediaStreams but not webRTC
      } else {
        // Safari UA substrings of interest for reference:
        // - webkit version:           AppleWebKit/602.1.25 (also used in Op,Cr)
        // - safari UI version:        Version/9.0.3 (unique to Safari)
        // - safari UI webkit version: Safari/601.4.4 (also used in Op,Cr)
        //
        // if the webkit version and safari UI webkit versions are equals,
        // ... this is a stable version.
        //
        // only the internal webkit version is important today to know if
        // media streams are supported
        //
        if (navigator.userAgent.match(/Version\/(\d+).(\d+)/)) {
          result.browser = 'safari';
          result.version = this.extractVersion(navigator.userAgent,
            /AppleWebKit\/([0-9]+)\./, 1);

        // unknown webkit-based browser
        } else {
          result.browser = 'Unsupported webkit-based browser ' +
              'with GUM support but no WebRTC support.';
          return result;
        }
      }

    // Edge.
    } else if (navigator.mediaDevices &&
        navigator.userAgent.match(/Edge\/(\d+).(\d+)$/)) {
      result.browser = 'edge';
      result.version = this.extractVersion(navigator.userAgent,
          /Edge\/(\d+).(\d+)$/, 2);

    // Default fallthrough: not supported.
    } else {
      result.browser = 'Not a supported browser.';
      return result;
    }

    return result;
  }
};

// Export.
module.exports = {
  log: utils.log,
  disableLog: utils.disableLog,
  browserDetails: utils.detectBrowser(),
  extractVersion: utils.extractVersion
};

},{}]},{},[8]);