/node_modules/socket.io/node_modules/socket.io-client/socket.io.js

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!function(e){if("object"==typeof exports&&"undefined"!=typeof module)module.exports=e();else if("function"==typeof define&&define.amd)define([],e);else{var f;"undefined"!=typeof window?f=window:"undefined"!=typeof global?f=global:"undefined"!=typeof self&&(f=self),f.io=e()}}(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);throw new Error("Cannot find module '"+o+"'")}var f=n[o]={exports:{}};t[o][0].call(f.exports,function(e){var n=t[o][1][e];return s(n?n:e)},f,f.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(_dereq_,module,exports){

module.exports = _dereq_('./lib/');

},{"./lib/":2}],2:[function(_dereq_,module,exports){

/**
 * Module dependencies.
 */

var url = _dereq_('./url');
var parser = _dereq_('socket.io-parser');
var Manager = _dereq_('./manager');
var debug = _dereq_('debug')('socket.io-client');

/**
 * Module exports.
 */

module.exports = exports = lookup;

/**
 * Managers cache.
 */

var cache = exports.managers = {};

/**
 * Looks up an existing `Manager` for multiplexing.
 * If the user summons:
 *
 *   `io('http://localhost/a');`
 *   `io('http://localhost/b');`
 *
 * We reuse the existing instance based on same scheme/port/host,
 * and we initialize sockets for each namespace.
 *
 * @api public
 */

function lookup(uri, opts) {
  if (typeof uri == 'object') {
    opts = uri;
    uri = undefined;
  }

  opts = opts || {};

  var parsed = url(uri);
  var source = parsed.source;
  var id = parsed.id;
  var io;

  if (opts.forceNew || opts['force new connection'] || false === opts.multiplex) {
    debug('ignoring socket cache for %s', source);
    io = Manager(source, opts);
  } else {
    if (!cache[id]) {
      debug('new io instance for %s', source);
      cache[id] = Manager(source, opts);
    }
    io = cache[id];
  }

  return io.socket(parsed.path);
}

/**
 * Protocol version.
 *
 * @api public
 */

exports.protocol = parser.protocol;

/**
 * `connect`.
 *
 * @param {String} uri
 * @api public
 */

exports.connect = lookup;

/**
 * Expose constructors for standalone build.
 *
 * @api public
 */

exports.Manager = _dereq_('./manager');
exports.Socket = _dereq_('./socket');

},{"./manager":3,"./socket":5,"./url":6,"debug":9,"socket.io-parser":40}],3:[function(_dereq_,module,exports){

/**
 * Module dependencies.
 */

var url = _dereq_('./url');
var eio = _dereq_('engine.io-client');
var Socket = _dereq_('./socket');
var Emitter = _dereq_('component-emitter');
var parser = _dereq_('socket.io-parser');
var on = _dereq_('./on');
var bind = _dereq_('component-bind');
var object = _dereq_('object-component');
var debug = _dereq_('debug')('socket.io-client:manager');
var indexOf = _dereq_('indexof');

/**
 * Module exports
 */

module.exports = Manager;

/**
 * `Manager` constructor.
 *
 * @param {String} engine instance or engine uri/opts
 * @param {Object} options
 * @api public
 */

function Manager(uri, opts){
  if (!(this instanceof Manager)) return new Manager(uri, opts);
  if (uri && ('object' == typeof uri)) {
    opts = uri;
    uri = undefined;
  }
  opts = opts || {};

  opts.path = opts.path || '/socket.io';
  this.nsps = {};
  this.subs = [];
  this.opts = opts;
  this.reconnection(opts.reconnection !== false);
  this.reconnectionAttempts(opts.reconnectionAttempts || Infinity);
  this.reconnectionDelay(opts.reconnectionDelay || 1000);
  this.reconnectionDelayMax(opts.reconnectionDelayMax || 5000);
  this.timeout(null == opts.timeout ? 20000 : opts.timeout);
  this.readyState = 'closed';
  this.uri = uri;
  this.connected = [];
  this.attempts = 0;
  this.encoding = false;
  this.packetBuffer = [];
  this.encoder = new parser.Encoder();
  this.decoder = new parser.Decoder();
  this.autoConnect = opts.autoConnect !== false;
  if (this.autoConnect) this.open();
}

/**
 * Propagate given event to sockets and emit on `this`
 *
 * @api private
 */

Manager.prototype.emitAll = function() {
  this.emit.apply(this, arguments);
  for (var nsp in this.nsps) {
    this.nsps[nsp].emit.apply(this.nsps[nsp], arguments);
  }
};

/**
 * Mix in `Emitter`.
 */

Emitter(Manager.prototype);

/**
 * Sets the `reconnection` config.
 *
 * @param {Boolean} true/false if it should automatically reconnect
 * @return {Manager} self or value
 * @api public
 */

Manager.prototype.reconnection = function(v){
  if (!arguments.length) return this._reconnection;
  this._reconnection = !!v;
  return this;
};

/**
 * Sets the reconnection attempts config.
 *
 * @param {Number} max reconnection attempts before giving up
 * @return {Manager} self or value
 * @api public
 */

Manager.prototype.reconnectionAttempts = function(v){
  if (!arguments.length) return this._reconnectionAttempts;
  this._reconnectionAttempts = v;
  return this;
};

/**
 * Sets the delay between reconnections.
 *
 * @param {Number} delay
 * @return {Manager} self or value
 * @api public
 */

Manager.prototype.reconnectionDelay = function(v){
  if (!arguments.length) return this._reconnectionDelay;
  this._reconnectionDelay = v;
  return this;
};

/**
 * Sets the maximum delay between reconnections.
 *
 * @param {Number} delay
 * @return {Manager} self or value
 * @api public
 */

Manager.prototype.reconnectionDelayMax = function(v){
  if (!arguments.length) return this._reconnectionDelayMax;
  this._reconnectionDelayMax = v;
  return this;
};

/**
 * Sets the connection timeout. `false` to disable
 *
 * @return {Manager} self or value
 * @api public
 */

Manager.prototype.timeout = function(v){
  if (!arguments.length) return this._timeout;
  this._timeout = v;
  return this;
};

/**
 * Starts trying to reconnect if reconnection is enabled and we have not
 * started reconnecting yet
 *
 * @api private
 */

Manager.prototype.maybeReconnectOnOpen = function() {
  // Only try to reconnect if it's the first time we're connecting
  if (!this.openReconnect && !this.reconnecting && this._reconnection && this.attempts === 0) {
    // keeps reconnection from firing twice for the same reconnection loop
    this.openReconnect = true;
    this.reconnect();
  }
};


/**
 * Sets the current transport `socket`.
 *
 * @param {Function} optional, callback
 * @return {Manager} self
 * @api public
 */

Manager.prototype.open =
Manager.prototype.connect = function(fn){
  debug('readyState %s', this.readyState);
  if (~this.readyState.indexOf('open')) return this;

  debug('opening %s', this.uri);
  this.engine = eio(this.uri, this.opts);
  var socket = this.engine;
  var self = this;
  this.readyState = 'opening';
  this.skipReconnect = false;

  // emit `open`
  var openSub = on(socket, 'open', function() {
    self.onopen();
    fn && fn();
  });

  // emit `connect_error`
  var errorSub = on(socket, 'error', function(data){
    debug('connect_error');
    self.cleanup();
    self.readyState = 'closed';
    self.emitAll('connect_error', data);
    if (fn) {
      var err = new Error('Connection error');
      err.data = data;
      fn(err);
    }

    self.maybeReconnectOnOpen();
  });

  // emit `connect_timeout`
  if (false !== this._timeout) {
    var timeout = this._timeout;
    debug('connect attempt will timeout after %d', timeout);

    // set timer
    var timer = setTimeout(function(){
      debug('connect attempt timed out after %d', timeout);
      openSub.destroy();
      socket.close();
      socket.emit('error', 'timeout');
      self.emitAll('connect_timeout', timeout);
    }, timeout);

    this.subs.push({
      destroy: function(){
        clearTimeout(timer);
      }
    });
  }

  this.subs.push(openSub);
  this.subs.push(errorSub);

  return this;
};

/**
 * Called upon transport open.
 *
 * @api private
 */

Manager.prototype.onopen = function(){
  debug('open');

  // clear old subs
  this.cleanup();

  // mark as open
  this.readyState = 'open';
  this.emit('open');

  // add new subs
  var socket = this.engine;
  this.subs.push(on(socket, 'data', bind(this, 'ondata')));
  this.subs.push(on(this.decoder, 'decoded', bind(this, 'ondecoded')));
  this.subs.push(on(socket, 'error', bind(this, 'onerror')));
  this.subs.push(on(socket, 'close', bind(this, 'onclose')));
};

/**
 * Called with data.
 *
 * @api private
 */

Manager.prototype.ondata = function(data){
  this.decoder.add(data);
};

/**
 * Called when parser fully decodes a packet.
 *
 * @api private
 */

Manager.prototype.ondecoded = function(packet) {
  this.emit('packet', packet);
};

/**
 * Called upon socket error.
 *
 * @api private
 */

Manager.prototype.onerror = function(err){
  debug('error', err);
  this.emitAll('error', err);
};

/**
 * Creates a new socket for the given `nsp`.
 *
 * @return {Socket}
 * @api public
 */

Manager.prototype.socket = function(nsp){
  var socket = this.nsps[nsp];
  if (!socket) {
    socket = new Socket(this, nsp);
    this.nsps[nsp] = socket;
    var self = this;
    socket.on('connect', function(){
      if (!~indexOf(self.connected, socket)) {
        self.connected.push(socket);
      }
    });
  }
  return socket;
};

/**
 * Called upon a socket close.
 *
 * @param {Socket} socket
 */

Manager.prototype.destroy = function(socket){
  var index = indexOf(this.connected, socket);
  if (~index) this.connected.splice(index, 1);
  if (this.connected.length) return;

  this.close();
};

/**
 * Writes a packet.
 *
 * @param {Object} packet
 * @api private
 */

Manager.prototype.packet = function(packet){
  debug('writing packet %j', packet);
  var self = this;

  if (!self.encoding) {
    // encode, then write to engine with result
    self.encoding = true;
    this.encoder.encode(packet, function(encodedPackets) {
      for (var i = 0; i < encodedPackets.length; i++) {
        self.engine.write(encodedPackets[i]);
      }
      self.encoding = false;
      self.processPacketQueue();
    });
  } else { // add packet to the queue
    self.packetBuffer.push(packet);
  }
};

/**
 * If packet buffer is non-empty, begins encoding the
 * next packet in line.
 *
 * @api private
 */

Manager.prototype.processPacketQueue = function() {
  if (this.packetBuffer.length > 0 && !this.encoding) {
    var pack = this.packetBuffer.shift();
    this.packet(pack);
  }
};

/**
 * Clean up transport subscriptions and packet buffer.
 *
 * @api private
 */

Manager.prototype.cleanup = function(){
  var sub;
  while (sub = this.subs.shift()) sub.destroy();

  this.packetBuffer = [];
  this.encoding = false;

  this.decoder.destroy();
};

/**
 * Close the current socket.
 *
 * @api private
 */

Manager.prototype.close =
Manager.prototype.disconnect = function(){
  this.skipReconnect = true;
  this.readyState = 'closed';
  this.engine && this.engine.close();
};

/**
 * Called upon engine close.
 *
 * @api private
 */

Manager.prototype.onclose = function(reason){
  debug('close');
  this.cleanup();
  this.readyState = 'closed';
  this.emit('close', reason);
  if (this._reconnection && !this.skipReconnect) {
    this.reconnect();
  }
};

/**
 * Attempt a reconnection.
 *
 * @api private
 */

Manager.prototype.reconnect = function(){
  if (this.reconnecting || this.skipReconnect) return this;

  var self = this;
  this.attempts++;

  if (this.attempts > this._reconnectionAttempts) {
    debug('reconnect failed');
    this.emitAll('reconnect_failed');
    this.reconnecting = false;
  } else {
    var delay = this.attempts * this.reconnectionDelay();
    delay = Math.min(delay, this.reconnectionDelayMax());
    debug('will wait %dms before reconnect attempt', delay);

    this.reconnecting = true;
    var timer = setTimeout(function(){
      if (self.skipReconnect) return;

      debug('attempting reconnect');
      self.emitAll('reconnect_attempt', self.attempts);
      self.emitAll('reconnecting', self.attempts);

      // check again for the case socket closed in above events
      if (self.skipReconnect) return;

      self.open(function(err){
        if (err) {
          debug('reconnect attempt error');
          self.reconnecting = false;
          self.reconnect();
          self.emitAll('reconnect_error', err.data);
        } else {
          debug('reconnect success');
          self.onreconnect();
        }
      });
    }, delay);

    this.subs.push({
      destroy: function(){
        clearTimeout(timer);
      }
    });
  }
};

/**
 * Called upon successful reconnect.
 *
 * @api private
 */

Manager.prototype.onreconnect = function(){
  var attempt = this.attempts;
  this.attempts = 0;
  this.reconnecting = false;
  this.emitAll('reconnect', attempt);
};

},{"./on":4,"./socket":5,"./url":6,"component-bind":7,"component-emitter":8,"debug":9,"engine.io-client":10,"indexof":36,"object-component":37,"socket.io-parser":40}],4:[function(_dereq_,module,exports){

/**
 * Module exports.
 */

module.exports = on;

/**
 * Helper for subscriptions.
 *
 * @param {Object|EventEmitter} obj with `Emitter` mixin or `EventEmitter`
 * @param {String} event name
 * @param {Function} callback
 * @api public
 */

function on(obj, ev, fn) {
  obj.on(ev, fn);
  return {
    destroy: function(){
      obj.removeListener(ev, fn);
    }
  };
}

},{}],5:[function(_dereq_,module,exports){

/**
 * Module dependencies.
 */

var parser = _dereq_('socket.io-parser');
var Emitter = _dereq_('component-emitter');
var toArray = _dereq_('to-array');
var on = _dereq_('./on');
var bind = _dereq_('component-bind');
var debug = _dereq_('debug')('socket.io-client:socket');
var hasBin = _dereq_('has-binary');

/**
 * Module exports.
 */

module.exports = exports = Socket;

/**
 * Internal events (blacklisted).
 * These events can't be emitted by the user.
 *
 * @api private
 */

var events = {
  connect: 1,
  connect_error: 1,
  connect_timeout: 1,
  disconnect: 1,
  error: 1,
  reconnect: 1,
  reconnect_attempt: 1,
  reconnect_failed: 1,
  reconnect_error: 1,
  reconnecting: 1
};

/**
 * Shortcut to `Emitter#emit`.
 */

var emit = Emitter.prototype.emit;

/**
 * `Socket` constructor.
 *
 * @api public
 */

function Socket(io, nsp){
  this.io = io;
  this.nsp = nsp;
  this.json = this; // compat
  this.ids = 0;
  this.acks = {};
  if (this.io.autoConnect) this.open();
  this.receiveBuffer = [];
  this.sendBuffer = [];
  this.connected = false;
  this.disconnected = true;
}

/**
 * Mix in `Emitter`.
 */

Emitter(Socket.prototype);

/**
 * Subscribe to open, close and packet events
 *
 * @api private
 */

Socket.prototype.subEvents = function() {
  if (this.subs) return;

  var io = this.io;
  this.subs = [
    on(io, 'open', bind(this, 'onopen')),
    on(io, 'packet', bind(this, 'onpacket')),
    on(io, 'close', bind(this, 'onclose'))
  ];
};

/**
 * "Opens" the socket.
 *
 * @api public
 */

Socket.prototype.open =
Socket.prototype.connect = function(){
  if (this.connected) return this;

  this.subEvents();
  this.io.open(); // ensure open
  if ('open' == this.io.readyState) this.onopen();
  return this;
};

/**
 * Sends a `message` event.
 *
 * @return {Socket} self
 * @api public
 */

Socket.prototype.send = function(){
  var args = toArray(arguments);
  args.unshift('message');
  this.emit.apply(this, args);
  return this;
};

/**
 * Override `emit`.
 * If the event is in `events`, it's emitted normally.
 *
 * @param {String} event name
 * @return {Socket} self
 * @api public
 */

Socket.prototype.emit = function(ev){
  if (events.hasOwnProperty(ev)) {
    emit.apply(this, arguments);
    return this;
  }

  var args = toArray(arguments);
  var parserType = parser.EVENT; // default
  if (hasBin(args)) { parserType = parser.BINARY_EVENT; } // binary
  var packet = { type: parserType, data: args };

  // event ack callback
  if ('function' == typeof args[args.length - 1]) {
    debug('emitting packet with ack id %d', this.ids);
    this.acks[this.ids] = args.pop();
    packet.id = this.ids++;
  }

  if (this.connected) {
    this.packet(packet);
  } else {
    this.sendBuffer.push(packet);
  }

  return this;
};

/**
 * Sends a packet.
 *
 * @param {Object} packet
 * @api private
 */

Socket.prototype.packet = function(packet){
  packet.nsp = this.nsp;
  this.io.packet(packet);
};

/**
 * Called upon engine `open`.
 *
 * @api private
 */

Socket.prototype.onopen = function(){
  debug('transport is open - connecting');

  // write connect packet if necessary
  if ('/' != this.nsp) {
    this.packet({ type: parser.CONNECT });
  }
};

/**
 * Called upon engine `close`.
 *
 * @param {String} reason
 * @api private
 */

Socket.prototype.onclose = function(reason){
  debug('close (%s)', reason);
  this.connected = false;
  this.disconnected = true;
  this.emit('disconnect', reason);
};

/**
 * Called with socket packet.
 *
 * @param {Object} packet
 * @api private
 */

Socket.prototype.onpacket = function(packet){
  if (packet.nsp != this.nsp) return;

  switch (packet.type) {
    case parser.CONNECT:
      this.onconnect();
      break;

    case parser.EVENT:
      this.onevent(packet);
      break;

    case parser.BINARY_EVENT:
      this.onevent(packet);
      break;

    case parser.ACK:
      this.onack(packet);
      break;

    case parser.BINARY_ACK:
      this.onack(packet);
      break;

    case parser.DISCONNECT:
      this.ondisconnect();
      break;

    case parser.ERROR:
      this.emit('error', packet.data);
      break;
  }
};

/**
 * Called upon a server event.
 *
 * @param {Object} packet
 * @api private
 */

Socket.prototype.onevent = function(packet){
  var args = packet.data || [];
  debug('emitting event %j', args);

  if (null != packet.id) {
    debug('attaching ack callback to event');
    args.push(this.ack(packet.id));
  }

  if (this.connected) {
    emit.apply(this, args);
  } else {
    this.receiveBuffer.push(args);
  }
};

/**
 * Produces an ack callback to emit with an event.
 *
 * @api private
 */

Socket.prototype.ack = function(id){
  var self = this;
  var sent = false;
  return function(){
    // prevent double callbacks
    if (sent) return;
    sent = true;
    var args = toArray(arguments);
    debug('sending ack %j', args);

    var type = hasBin(args) ? parser.BINARY_ACK : parser.ACK;
    self.packet({
      type: type,
      id: id,
      data: args
    });
  };
};

/**
 * Called upon a server acknowlegement.
 *
 * @param {Object} packet
 * @api private
 */

Socket.prototype.onack = function(packet){
  debug('calling ack %s with %j', packet.id, packet.data);
  var fn = this.acks[packet.id];
  fn.apply(this, packet.data);
  delete this.acks[packet.id];
};

/**
 * Called upon server connect.
 *
 * @api private
 */

Socket.prototype.onconnect = function(){
  this.connected = true;
  this.disconnected = false;
  this.emit('connect');
  this.emitBuffered();
};

/**
 * Emit buffered events (received and emitted).
 *
 * @api private
 */

Socket.prototype.emitBuffered = function(){
  var i;
  for (i = 0; i < this.receiveBuffer.length; i++) {
    emit.apply(this, this.receiveBuffer[i]);
  }
  this.receiveBuffer = [];

  for (i = 0; i < this.sendBuffer.length; i++) {
    this.packet(this.sendBuffer[i]);
  }
  this.sendBuffer = [];
};

/**
 * Called upon server disconnect.
 *
 * @api private
 */

Socket.prototype.ondisconnect = function(){
  debug('server disconnect (%s)', this.nsp);
  this.destroy();
  this.onclose('io server disconnect');
};

/**
 * Called upon forced client/server side disconnections,
 * this method ensures the manager stops tracking us and
 * that reconnections don't get triggered for this.
 *
 * @api private.
 */

Socket.prototype.destroy = function(){
  if (this.subs) {
    // clean subscriptions to avoid reconnections
    for (var i = 0; i < this.subs.length; i++) {
      this.subs[i].destroy();
    }
    this.subs = null;
  }

  this.io.destroy(this);
};

/**
 * Disconnects the socket manually.
 *
 * @return {Socket} self
 * @api public
 */

Socket.prototype.close =
Socket.prototype.disconnect = function(){
  if (this.connected) {
    debug('performing disconnect (%s)', this.nsp);
    this.packet({ type: parser.DISCONNECT });
  }

  // remove socket from pool
  this.destroy();

  if (this.connected) {
    // fire events
    this.onclose('io client disconnect');
  }
  return this;
};

},{"./on":4,"component-bind":7,"component-emitter":8,"debug":9,"has-binary":32,"socket.io-parser":40,"to-array":44}],6:[function(_dereq_,module,exports){
(function (global){

/**
 * Module dependencies.
 */

var parseuri = _dereq_('parseuri');
var debug = _dereq_('debug')('socket.io-client:url');

/**
 * Module exports.
 */

module.exports = url;

/**
 * URL parser.
 *
 * @param {String} url
 * @param {Object} An object meant to mimic window.location.
 *                 Defaults to window.location.
 * @api public
 */

function url(uri, loc){
  var obj = uri;

  // default to window.location
  var loc = loc || global.location;
  if (null == uri) uri = loc.protocol + '//' + loc.hostname;

  // relative path support
  if ('string' == typeof uri) {
    if ('/' == uri.charAt(0)) {
      if ('/' == uri.charAt(1)) {
        uri = loc.protocol + uri;
      } else {
        uri = loc.hostname + uri;
      }
    }

    if (!/^(https?|wss?):\/\//.test(uri)) {
      debug('protocol-less url %s', uri);
      if ('undefined' != typeof loc) {
        uri = loc.protocol + '//' + uri;
      } else {
        uri = 'https://' + uri;
      }
    }

    // parse
    debug('parse %s', uri);
    obj = parseuri(uri);
  }

  // make sure we treat `localhost:80` and `localhost` equally
  if (!obj.port) {
    if (/^(http|ws)$/.test(obj.protocol)) {
      obj.port = '80';
    }
    else if (/^(http|ws)s$/.test(obj.protocol)) {
      obj.port = '443';
    }
  }

  obj.path = obj.path || '/';

  // define unique id
  obj.id = obj.protocol + '://' + obj.host + ':' + obj.port;
  // define href
  obj.href = obj.protocol + '://' + obj.host + (loc && loc.port == obj.port ? '' : (':' + obj.port));

  return obj;
}

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"debug":9,"parseuri":38}],7:[function(_dereq_,module,exports){
/**
 * Slice reference.
 */

var slice = [].slice;

/**
 * Bind `obj` to `fn`.
 *
 * @param {Object} obj
 * @param {Function|String} fn or string
 * @return {Function}
 * @api public
 */

module.exports = function(obj, fn){
  if ('string' == typeof fn) fn = obj[fn];
  if ('function' != typeof fn) throw new Error('bind() requires a function');
  var args = slice.call(arguments, 2);
  return function(){
    return fn.apply(obj, args.concat(slice.call(arguments)));
  }
};

},{}],8:[function(_dereq_,module,exports){

/**
 * Expose `Emitter`.
 */

module.exports = Emitter;

/**
 * Initialize a new `Emitter`.
 *
 * @api public
 */

function Emitter(obj) {
  if (obj) return mixin(obj);
};

/**
 * Mixin the emitter properties.
 *
 * @param {Object} obj
 * @return {Object}
 * @api private
 */

function mixin(obj) {
  for (var key in Emitter.prototype) {
    obj[key] = Emitter.prototype[key];
  }
  return obj;
}

/**
 * Listen on the given `event` with `fn`.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.on =
Emitter.prototype.addEventListener = function(event, fn){
  this._callbacks = this._callbacks || {};
  (this._callbacks[event] = this._callbacks[event] || [])
    .push(fn);
  return this;
};

/**
 * Adds an `event` listener that will be invoked a single
 * time then automatically removed.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.once = function(event, fn){
  var self = this;
  this._callbacks = this._callbacks || {};

  function on() {
    self.off(event, on);
    fn.apply(this, arguments);
  }

  on.fn = fn;
  this.on(event, on);
  return this;
};

/**
 * Remove the given callback for `event` or all
 * registered callbacks.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.off =
Emitter.prototype.removeListener =
Emitter.prototype.removeAllListeners =
Emitter.prototype.removeEventListener = function(event, fn){
  this._callbacks = this._callbacks || {};

  // all
  if (0 == arguments.length) {
    this._callbacks = {};
    return this;
  }

  // specific event
  var callbacks = this._callbacks[event];
  if (!callbacks) return this;

  // remove all handlers
  if (1 == arguments.length) {
    delete this._callbacks[event];
    return this;
  }

  // remove specific handler
  var cb;
  for (var i = 0; i < callbacks.length; i++) {
    cb = callbacks[i];
    if (cb === fn || cb.fn === fn) {
      callbacks.splice(i, 1);
      break;
    }
  }
  return this;
};

/**
 * Emit `event` with the given args.
 *
 * @param {String} event
 * @param {Mixed} ...
 * @return {Emitter}
 */

Emitter.prototype.emit = function(event){
  this._callbacks = this._callbacks || {};
  var args = [].slice.call(arguments, 1)
    , callbacks = this._callbacks[event];

  if (callbacks) {
    callbacks = callbacks.slice(0);
    for (var i = 0, len = callbacks.length; i < len; ++i) {
      callbacks[i].apply(this, args);
    }
  }

  return this;
};

/**
 * Return array of callbacks for `event`.
 *
 * @param {String} event
 * @return {Array}
 * @api public
 */

Emitter.prototype.listeners = function(event){
  this._callbacks = this._callbacks || {};
  return this._callbacks[event] || [];
};

/**
 * Check if this emitter has `event` handlers.
 *
 * @param {String} event
 * @return {Boolean}
 * @api public
 */

Emitter.prototype.hasListeners = function(event){
  return !! this.listeners(event).length;
};

},{}],9:[function(_dereq_,module,exports){

/**
 * Expose `debug()` as the module.
 */

module.exports = debug;

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

function debug(name) {
  if (!debug.enabled(name)) return function(){};

  return function(fmt){
    fmt = coerce(fmt);

    var curr = new Date;
    var ms = curr - (debug[name] || curr);
    debug[name] = curr;

    fmt = name
      + ' '
      + fmt
      + ' +' + debug.humanize(ms);

    // This hackery is required for IE8
    // where `console.log` doesn't have 'apply'
    window.console
      && console.log
      && Function.prototype.apply.call(console.log, console, arguments);
  }
}

/**
 * The currently active debug mode names.
 */

debug.names = [];
debug.skips = [];

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

debug.enable = function(name) {
  try {
    localStorage.debug = name;
  } catch(e){}

  var split = (name || '').split(/[\s,]+/)
    , len = split.length;

  for (var i = 0; i < len; i++) {
    name = split[i].replace('*', '.*?');
    if (name[0] === '-') {
      debug.skips.push(new RegExp('^' + name.substr(1) + '$'));
    }
    else {
      debug.names.push(new RegExp('^' + name + '$'));
    }
  }
};

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

debug.disable = function(){
  debug.enable('');
};

/**
 * Humanize the given `ms`.
 *
 * @param {Number} m
 * @return {String}
 * @api private
 */

debug.humanize = function(ms) {
  var sec = 1000
    , min = 60 * 1000
    , hour = 60 * min;

  if (ms >= hour) return (ms / hour).toFixed(1) + 'h';
  if (ms >= min) return (ms / min).toFixed(1) + 'm';
  if (ms >= sec) return (ms / sec | 0) + 's';
  return ms + 'ms';
};

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

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

/**
 * Coerce `val`.
 */

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

// persist

try {
  if (window.localStorage) debug.enable(localStorage.debug);
} catch(e){}

},{}],10:[function(_dereq_,module,exports){

module.exports =  _dereq_('./lib/');

},{"./lib/":11}],11:[function(_dereq_,module,exports){

module.exports = _dereq_('./socket');

/**
 * Exports parser
 *
 * @api public
 *
 */
module.exports.parser = _dereq_('engine.io-parser');

},{"./socket":12,"engine.io-parser":21}],12:[function(_dereq_,module,exports){
(function (global){
/**
 * Module dependencies.
 */

var transports = _dereq_('./transports');
var Emitter = _dereq_('component-emitter');
var debug = _dereq_('debug')('engine.io-client:socket');
var index = _dereq_('indexof');
var parser = _dereq_('engine.io-parser');
var parseuri = _dereq_('parseuri');
var parsejson = _dereq_('parsejson');
var parseqs = _dereq_('parseqs');

/**
 * Module exports.
 */

module.exports = Socket;

/**
 * Noop function.
 *
 * @api private
 */

function noop(){}

/**
 * Socket constructor.
 *
 * @param {String|Object} uri or options
 * @param {Object} options
 * @api public
 */

function Socket(uri, opts){
  if (!(this instanceof Socket)) return new Socket(uri, opts);

  opts = opts || {};

  if (uri && 'object' == typeof uri) {
    opts = uri;
    uri = null;
  }

  if (uri) {
    uri = parseuri(uri);
    opts.host = uri.host;
    opts.secure = uri.protocol == 'https' || uri.protocol == 'wss';
    opts.port = uri.port;
    if (uri.query) opts.query = uri.query;
  }

  this.secure = null != opts.secure ? opts.secure :
    (global.location && 'https:' == location.protocol);

  if (opts.host) {
    var pieces = opts.host.split(':');
    opts.hostname = pieces.shift();
    if (pieces.length) opts.port = pieces.pop();
  }

  this.agent = opts.agent || false;
  this.hostname = opts.hostname ||
    (global.location ? location.hostname : 'localhost');
  this.port = opts.port || (global.location && location.port ?
       location.port :
       (this.secure ? 443 : 80));
  this.query = opts.query || {};
  if ('string' == typeof this.query) this.query = parseqs.decode(this.query);
  this.upgrade = false !== opts.upgrade;
  this.path = (opts.path || '/engine.io').replace(/\/$/, '') + '/';
  this.forceJSONP = !!opts.forceJSONP;
  this.jsonp = false !== opts.jsonp;
  this.forceBase64 = !!opts.forceBase64;
  this.enablesXDR = !!opts.enablesXDR;
  this.timestampParam = opts.timestampParam || 't';
  this.timestampRequests = opts.timestampRequests;
  this.transports = opts.transports || ['polling', 'websocket'];
  this.readyState = '';
  this.writeBuffer = [];
  this.callbackBuffer = [];
  this.policyPort = opts.policyPort || 843;
  this.rememberUpgrade = opts.rememberUpgrade || false;
  this.open();
  this.binaryType = null;
  this.onlyBinaryUpgrades = opts.onlyBinaryUpgrades;
}

Socket.priorWebsocketSuccess = false;

/**
 * Mix in `Emitter`.
 */

Emitter(Socket.prototype);

/**
 * Protocol version.
 *
 * @api public
 */

Socket.protocol = parser.protocol; // this is an int

/**
 * Expose deps for legacy compatibility
 * and standalone browser access.
 */

Socket.Socket = Socket;
Socket.Transport = _dereq_('./transport');
Socket.transports = _dereq_('./transports');
Socket.parser = _dereq_('engine.io-parser');

/**
 * Creates transport of the given type.
 *
 * @param {String} transport name
 * @return {Transport}
 * @api private
 */

Socket.prototype.createTransport = function (name) {
  debug('creating transport "%s"', name);
  var query = clone(this.query);

  // append engine.io protocol identifier
  query.EIO = parser.protocol;

  // transport name
  query.transport = name;

  // session id if we already have one
  if (this.id) query.sid = this.id;

  var transport = new transports[name]({
    agent: this.agent,
    hostname: this.hostname,
    port: this.port,
    secure: this.secure,
    path: this.path,
    query: query,
    forceJSONP: this.forceJSONP,
    jsonp: this.jsonp,
    forceBase64: this.forceBase64,
    enablesXDR: this.enablesXDR,
    timestampRequests: this.timestampRequests,
    timestampParam: this.timestampParam,
    policyPort: this.policyPort,
    socket: this
  });

  return transport;
};

function clone (obj) {
  var o = {};
  for (var i in obj) {
    if (obj.hasOwnProperty(i)) {
      o[i] = obj[i];
    }
  }
  return o;
}

/**
 * Initializes transport to use and starts probe.
 *
 * @api private
 */
Socket.prototype.open = function () {
  var transport;
  if (this.rememberUpgrade && Socket.priorWebsocketSuccess && this.transports.indexOf('websocket') != -1) {
    transport = 'websocket';
  } else if (0 == this.transports.length) {
    // Emit error on next tick so it can be listened to
    var self = this;
    setTimeout(function() {
      self.emit('error', 'No transports available');
    }, 0);
    return;
  } else {
    transport = this.transports[0];
  }
  this.readyState = 'opening';

  // Retry with the next transport if the transport is disabled (jsonp: false)
  var transport;
  try {
    transport = this.createTransport(transport);
  } catch (e) {
    this.transports.shift();
    this.open();
    return;
  }

  transport.open();
  this.setTransport(transport);
};

/**
 * Sets the current transport. Disables the existing one (if any).
 *
 * @api private
 */

Socket.prototype.setTransport = function(transport){
  debug('setting transport %s', transport.name);
  var self = this;

  if (this.transport) {
    debug('clearing existing transport %s', this.transport.name);
    this.transport.removeAllListeners();
  }

  // set up transport
  this.transport = transport;

  // set up transport listeners
  transport
  .on('drain', function(){
    self.onDrain();
  })
  .on('packet', function(packet){
    self.onPacket(packet);
  })
  .on('error', function(e){
    self.onError(e);
  })
  .on('close', function(){
    self.onClose('transport close');
  });
};

/**
 * Probes a transport.
 *
 * @param {String} transport name
 * @api private
 */

Socket.prototype.probe = function (name) {
  debug('probing transport "%s"', name);
  var transport = this.createTransport(name, { probe: 1 })
    , failed = false
    , self = this;

  Socket.priorWebsocketSuccess = false;

  function onTransportOpen(){
    if (self.onlyBinaryUpgrades) {
      var upgradeLosesBinary = !this.supportsBinary && self.transport.supportsBinary;
      failed = failed || upgradeLosesBinary;
    }
    if (failed) return;

    debug('probe transport "%s" opened', name);
    transport.send([{ type: 'ping', data: 'probe' }]);
    transport.once('packet', function (msg) {
      if (failed) return;
      if ('pong' == msg.type && 'probe' == msg.data) {
        debug('probe transport "%s" pong', name);
        self.upgrading = true;
        self.emit('upgrading', transport);
        if (!transport) return;
        Socket.priorWebsocketSuccess = 'websocket' == transport.name;

        debug('pausing current transport "%s"', self.transport.name);
        self.transport.pause(function () {
          if (failed) return;
          if ('closed' == self.readyState) return;
          debug('changing transport and sending upgrade packet');

          cleanup();

          self.setTransport(transport);
          transport.send([{ type: 'upgrade' }]);
          self.emit('upgrade', transport);
          transport = null;
          self.upgrading = false;
          self.flush();
        });
      } else {
        debug('probe transport "%s" failed', name);
        var err = new Error('probe error');
        err.transport = transport.name;
        self.emit('upgradeError', err);
      }
    });
  }

  function freezeTransport() {
    if (failed) return;

    // Any callback called by transport should be ignored since now
    failed = true;

    cleanup();

    transport.close();
    transport = null;
  }

  //Handle any error that happens while probing
  function onerror(err) {
    var error = new Error('probe error: ' + err);
    error.transport = transport.name;

    freezeTransport();

    debug('probe transport "%s" failed because of error: %s', name, err);

    self.emit('upgradeError', error);
  }

  function onTransportClose(){
    onerror("transport closed");
  }

  //When the socket is closed while we're probing
  function onclose(){
    onerror("socket closed");
  }

  //When the socket is upgraded while we're probing
  function onupgrade(to){
    if (transport && to.name != transport.name) {
      debug('"%s" works - aborting "%s"', to.name, transport.name);
      freezeTransport();
    }
  }

  //Remove all listeners on the transport and on self
  function cleanup(){
    transport.removeListener('open', onTransportOpen);
    transport.removeListener('error', onerror);
    transport.removeListener('close', onTransportClose);
    self.removeListener('close', onclose);
    self.removeListener('upgrading', onupgrade);
  }

  transport.once('open', onTransportOpen);
  transport.once('error', onerror);
  transport.once('close', onTransportClose);

  this.once('close', onclose);
  this.once('upgrading', onupgrade);

  transport.open();

};

/**
 * Called when connection is deemed open.
 *
 * @api public
 */

Socket.prototype.onOpen = function () {
  debug('socket open');
  this.readyState = 'open';
  Socket.priorWebsocketSuccess = 'websocket' == this.transport.name;
  this.emit('open');
  this.flush();

  // we check for `readyState` in case an `open`
  // listener already closed the socket
  if ('open' == this.readyState && this.upgrade && this.transport.pause) {
    debug('starting upgrade probes');
    for (var i = 0, l = this.upgrades.length; i < l; i++) {
      this.probe(this.upgrades[i]);
    }
  }
};

/**
 * Handles a packet.
 *
 * @api private
 */

Socket.prototype.onPacket = function (packet) {
  if ('opening' == this.readyState || 'open' == this.readyState) {
    debug('socket receive: type "%s", data "%s"', packet.type, packet.data);

    this.emit('packet', packet);

    // Socket is live - any packet counts
    this.emit('heartbeat');

    switch (packet.type) {
      case 'open':
        this.onHandshake(parsejson(packet.data));
        break;

      case 'pong':
        this.setPing();
        break;

      case 'error':
        var err = new Error('server error');
        err.code = packet.data;
        this.emit('error', err);
        break;

      case 'message':
        this.emit('data', packet.data);
        this.emit('message', packet.data);
        break;
    }
  } else {
    debug('packet received with socket readyState "%s"', this.readyState);
  }
};

/**
 * Called upon handshake completion.
 *
 * @param {Object} handshake obj
 * @api private
 */

Socket.prototype.onHandshake = function (data) {
  this.emit('handshake', data);
  this.id = data.sid;
  this.transport.query.sid = data.sid;
  this.upgrades = this.filterUpgrades(data.upgrades);
  this.pingInterval = data.pingInterval;
  this.pingTimeout = data.pingTimeout;
  this.onOpen();
  // In case open handler closes socket
  if  ('closed' == this.readyState) return;
  this.setPing();

  // Prolong liveness of socket on heartbeat
  this.removeListener('heartbeat', this.onHeartbeat);
  this.on('heartbeat', this.onHeartbeat);
};

/**
 * Resets ping timeout.
 *
 * @api private
 */

Socket.prototype.onHeartbeat = function (timeout) {
  clearTimeout(this.pingTimeoutTimer);
  var self = this;
  self.pingTimeoutTimer = setTimeout(function () {
    if ('closed' == self.readyState) return;
    self.onClose('ping timeout');
  }, timeout || (self.pingInterval + self.pingTimeout));
};

/**
 * Pings server every `this.pingInterval` and expects response
 * within `this.pingTimeout` or closes connection.
 *
 * @api private
 */

Socket.prototype.setPing = function () {
  var self = this;
  clearTimeout(self.pingIntervalTimer);
  self.pingIntervalTimer = setTimeout(function () {
    debug('writing ping packet - expecting pong within %sms', self.pingTimeout);
    self.ping();
    self.onHeartbeat(self.pingTimeout);
  }, self.pingInterval);
};

/**
* Sends a ping packet.
*
* @api public
*/

Socket.prototype.ping = function () {
  this.sendPacket('ping');
};

/**
 * Called on `drain` event
 *
 * @api private
 */

Socket.prototype.onDrain = function() {
  for (var i = 0; i < this.prevBufferLen; i++) {
    if (this.callbackBuffer[i]) {
      this.callbackBuffer[i]();
    }
  }

  this.writeBuffer.splice(0, this.prevBufferLen);
  this.callbackBuffer.splice(0, this.prevBufferLen);

  // setting prevBufferLen = 0 is very important
  // for example, when upgrading, upgrade packet is sent over,
  // and a nonzero prevBufferLen could cause problems on `drain`
  this.prevBufferLen = 0;

  if (this.writeBuffer.length == 0) {
    this.emit('drain');
  } else {
    this.flush();
  }
};

/**
 * Flush write buffers.
 *
 * @api private
 */

Socket.prototype.flush = function () {
  if ('closed' != this.readyState && this.transport.writable &&
    !this.upgrading && this.writeBuffer.length) {
    debug('flushing %d packets in socket', this.writeBuffer.length);
    this.transport.send(this.writeBuffer);
    // keep track of current length of writeBuffer
    // splice writeBuffer and callbackBuffer on `drain`
    this.prevBufferLen = this.writeBuffer.length;
    this.emit('flush');
  }
};

/**
 * Sends a message.
 *
 * @param {String} message.
 * @param {Function} callback function.
 * @return {Socket} for chaining.
 * @api public
 */

Socket.prototype.write =
Socket.prototype.send = function (msg, fn) {
  this.sendPacket('message', msg, fn);
  return this;
};

/**
 * Sends a packet.
 *
 * @param {String} packet type.
 * @param {String} data.
 * @param {Function} callback function.
 * @api private
 */

Socket.prototype.sendPacket = function (type, data, fn) {
  if ('closing' == this.readyState || 'closed' == this.readyState) {
    return;
  }

  var packet = { type: type, data: data };
  this.emit('packetCreate', packet);
  this.writeBuffer.push(packet);
  this.callbackBuffer.push(fn);
  this.flush();
};

/**
 * Closes the connection.
 *
 * @api private
 */

Socket.prototype.close = function () {
  if ('opening' == this.readyState || 'open' == this.readyState) {
    this.readyState = 'closing';

    var self = this;

    function close() {
      self.onClose('forced close');
      debug('socket closing - telling transport to close');
      self.transport.close();
    }

    function cleanupAndClose() {
      self.removeListener('upgrade', cleanupAndClose);
      self.removeListener('upgradeError', cleanupAndClose);
      close();
    }

    function waitForUpgrade() {
      // wait for upgrade to finish since we can't send packets while pausing a transport
      self.once('upgrade', cleanupAndClose);
      self.once('upgradeError', cleanupAndClose);
    }

    if (this.writeBuffer.length) {
      this.once('drain', function() {
        if (this.upgrading) {
          waitForUpgrade();
        } else {
          close();
        }
      });
    } else if (this.upgrading) {
      waitForUpgrade();
    } else {
      close();
    }
  }

  return this;
};

/**
 * Called upon transport error
 *
 * @api private
 */

Socket.prototype.onError = function (err) {
  debug('socket error %j', err);
  Socket.priorWebsocketSuccess = false;
  this.emit('error', err);
  this.onClose('transport error', err);
};

/**
 * Called upon transport close.
 *
 * @api private
 */

Socket.prototype.onClose = function (reason, desc) {
  if ('opening' == this.readyState || 'open' == this.readyState || 'closing' == this.readyState) {
    debug('socket close with reason: "%s"', reason);
    var self = this;

    // clear timers
    clearTimeout(this.pingIntervalTimer);
    clearTimeout(this.pingTimeoutTimer);

    // clean buffers in next tick, so developers can still
    // grab the buffers on `close` event
    setTimeout(function() {
      self.writeBuffer = [];
      self.callbackBuffer = [];
      self.prevBufferLen = 0;
    }, 0);

    // stop event from firing again for transport
    this.transport.removeAllListeners('close');

    // ensure transport won't stay open
    this.transport.close();

    // ignore further transport communication
    this.transport.removeAllListeners();

    // set ready state
    this.readyState = 'closed';

    // clear session id
    this.id = null;

    // emit close event
    this.emit('close', reason, desc);
  }
};

/**
 * Filters upgrades, returning only those matching client transports.
 *
 * @param {Array} server upgrades
 * @api private
 *
 */

Socket.prototype.filterUpgrades = function (upgrades) {
  var filteredUpgrades = [];
  for (var i = 0, j = upgrades.length; i<j; i++) {
    if (~index(this.transports, upgrades[i])) filteredUpgrades.push(upgrades[i]);
  }
  return filteredUpgrades;
};

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"./transport":13,"./transports":14,"component-emitter":8,"debug":9,"engine.io-parser":21,"indexof":36,"parsejson":28,"parseqs":29,"parseuri":30}],13:[function(_dereq_,module,exports){
/**
 * Module dependencies.
 */

var parser = _dereq_('engine.io-parser');
var Emitter = _dereq_('component-emitter');

/**
 * Module exports.
 */

module.exports = Transport;

/**
 * Transport abstract constructor.
 *
 * @param {Object} options.
 * @api private
 */

function Transport (opts) {
  this.path = opts.path;
  this.hostname = opts.hostname;
  this.port = opts.port;
  this.secure = opts.secure;
  this.query = opts.query;
  this.timestampParam = opts.timestampParam;
  this.timestampRequests = opts.timestampRequests;
  this.readyState = '';
  this.agent = opts.agent || false;
  this.socket = opts.socket;
  this.enablesXDR = opts.enablesXDR;
}

/**
 * Mix in `Emitter`.
 */

Emitter(Transport.prototype);

/**
 * A counter used to prevent collisions in the timestamps used
 * for cache busting.
 */

Transport.timestamps = 0;

/**
 * Emits an error.
 *
 * @param {String} str
 * @return {Transport} for chaining
 * @api public
 */

Transport.prototype.onError = function (msg, desc) {
  var err = new Error(msg);
  err.type = 'TransportError';
  err.description = desc;
  this.emit('error', err);
  return this;
};

/**
 * Opens the transport.
 *
 * @api public
 */

Transport.prototype.open = function () {
  if ('closed' == this.readyState || '' == this.readyState) {
    this.readyState = 'opening';
    this.doOpen();
  }

  return this;
};

/**
 * Closes the transport.
 *
 * @api private
 */

Transport.prototype.close = function () {
  if ('opening' == this.readyState || 'open' == this.readyState) {
    this.doClose();
    this.onClose();
  }

  return this;
};

/**
 * Sends multiple packets.
 *
 * @param {Array} packets
 * @api private
 */

Transport.prototype.send = function(packets){
  if ('open' == this.readyState) {
    this.write(packets);
  } else {
    throw new Error('Transport not open');
  }
};

/**
 * Called upon open
 *
 * @api private
 */

Transport.prototype.onOpen = function () {
  this.readyState = 'open';
  this.writable = true;
  this.emit('open');
};

/**
 * Called with data.
 *
 * @param {String} data
 * @api private
 */

Transport.prototype.onData = function(data){
  var packet = parser.decodePacket(data, this.socket.binaryType);
  this.onPacket(packet);
};

/**
 * Called with a decoded packet.
 */

Transport.prototype.onPacket = function (packet) {
  this.emit('packet', packet);
};

/**
 * Called upon close.
 *
 * @api private
 */

Transport.prototype.onClose = function () {
  this.readyState = 'closed';
  this.emit('close');
};

},{"component-emitter":8,"engine.io-parser":21}],14:[function(_dereq_,module,exports){
(function (global){
/**
 * Module dependencies
 */

var XMLHttpRequest = _dereq_('xmlhttprequest');
var XHR = _dereq_('./polling-xhr');
var JSONP = _dereq_('./polling-jsonp');
var websocket = _dereq_('./websocket');

/**
 * Export transports.
 */

exports.polling = polling;
exports.websocket = websocket;

/**
 * Polling transport polymorphic constructor.
 * Decides on xhr vs jsonp based on feature detection.
 *
 * @api private
 */

function polling(opts){
  var xhr;
  var xd = false;
  var xs = false;
  var jsonp = false !== opts.jsonp;

  if (global.location) {
    var isSSL = 'https:' == location.protocol;
    var port = location.port;

    // some user agents have empty `location.port`
    if (!port) {
      port = isSSL ? 443 : 80;
    }

    xd = opts.hostname != location.hostname || port != opts.port;
    xs = opts.secure != isSSL;
  }

  opts.xdomain = xd;
  opts.xscheme = xs;
  xhr = new XMLHttpRequest(opts);

  if ('open' in xhr && !opts.forceJSONP) {
    return new XHR(opts);
  } else {
    if (!jsonp) throw new Error('JSONP disabled');
    return new JSONP(opts);
  }
}

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"./polling-jsonp":15,"./polling-xhr":16,"./websocket":18,"xmlhttprequest":19}],15:[function(_dereq_,module,exports){
(function (global){

/**
 * Module requirements.
 */

var Polling = _dereq_('./polling');
var inherit = _dereq_('component-inherit');

/**
 * Module exports.
 */

module.exports = JSONPPolling;

/**
 * Cached regular expressions.
 */

var rNewline = /\n/g;
var rEscapedNewline = /\\n/g;

/**
 * Global JSONP callbacks.
 */

var callbacks;

/**
 * Callbacks count.
 */

var index = 0;

/**
 * Noop.
 */

function empty () { }

/**
 * JSONP Polling constructor.
 *
 * @param {Object} opts.
 * @api public
 */

function JSONPPolling (opts) {
  Polling.call(this, opts);

  this.query = this.query || {};

  // define global callbacks array if not present
  // we do this here (lazily) to avoid unneeded global pollution
  if (!callbacks) {
    // we need to consider multiple engines in the same page
    if (!global.___eio) global.___eio = [];
    callbacks = global.___eio;
  }

  // callback identifier
  this.index = callbacks.length;

  // add callback to jsonp global
  var self = this;
  callbacks.push(function (msg) {
    self.onData(msg);
  });

  // append t…