text: /*!
   * ws: a node.js websocket client
   * Copyright(c) 2011 Einar Otto Stangvik <einaros@gmail.com>
   * MIT Licensed
   */
  
  'use strict';
  
  const EventEmitter = require('events');
  const crypto = require('crypto');
  const Ultron = require('ultron');
  const https = require('https');
  const http = require('http');
  const url = require('url');
  
  const PerMessageDeflate = require('./permessage-deflate');
  const EventTarget = require('./event-target');
  const extension = require('./extension');
  const constants = require('./constants');
  const Receiver = require('./receiver');
  const Sender = require('./sender');
  
  const readyStates = ['CONNECTING', 'OPEN', 'CLOSING', 'CLOSED'];
  const protocolVersions = [8, 13];
  const closeTimeout = 30 * 1000; // Allow 30 seconds to terminate the connection cleanly.
  
  /**
   * Class representing a WebSocket.
   *
   * @extends EventEmitter
   */
  class WebSocket extends EventEmitter {
    /**
     * Create a new `WebSocket`.
     *
     * @param {String} address The URL to which to connect
     * @param {(String|String[])} protocols The subprotocols
     * @param {Object} options Connection options
     */
    constructor (address, protocols, options) {
      super();
  
      this.readyState = WebSocket.CONNECTING;
      this.protocol = '';
  
      this._binaryType = constants.BINARY_TYPES[0];
      this._finalize = this.finalize.bind(this);
      this._closeFrameReceived = false;
      this._closeFrameSent = false;
      this._closeMessage = '';
      this._closeTimer = null;
      this._finalized = false;
      this._closeCode = 1006;
      this._extensions = {};
      this._isServer = true;
      this._receiver = null;
      this._sender = null;
      this._socket = null;
      this._ultron = null;
  
      if (address !== null) {
        if (!protocols) {
          protocols = [];
        } else if (typeof protocols === 'string') {
          protocols = [protocols];
        } else if (!Array.isArray(protocols)) {
          options = protocols;
          protocols = [];
        }
  
        initAsClient.call(this, address, protocols, options);
      }
    }
  
    get CONNECTING () { return WebSocket.CONNECTING; }
    get CLOSING () { return WebSocket.CLOSING; }
    get CLOSED () { return WebSocket.CLOSED; }
    get OPEN () { return WebSocket.OPEN; }
  
    /**
     * This deviates from the WHATWG interface since ws doesn't support the required
     * default "blob" type (instead we define a custom "nodebuffer" type).
     *
     * @type {String}
     */
    get binaryType () {
      return this._binaryType;
    }
  
    set binaryType (type) {
      if (constants.BINARY_TYPES.indexOf(type) < 0) return;
  
      this._binaryType = type;
  
      //
      // Allow to change `binaryType` on the fly.
      //
      if (this._receiver) this._receiver._binaryType = type;
    }
  
    /**
     * @type {Number}
     */
    get bufferedAmount () {
      var amount = 0;
  
      if (this._socket) {
        amount = this._socket.bufferSize + this._sender._bufferedBytes;
      }
      return amount;
    }
  
    /**
     * @type {String}
     */
    get extensions () {
      return Object.keys(this._extensions).join();
    }
  
    /**
     * Set up the socket and the internal resources.
     *
     * @param {net.Socket} socket The network socket between the server and client
     * @param {Buffer} head The first packet of the upgraded stream
     * @param {Number} maxPayload The maximum allowed message size
     * @private
     */
    setSocket (socket, head, maxPayload) {
      socket.setTimeout(0);
      socket.setNoDelay();
  
      this._receiver = new Receiver(this._extensions, maxPayload, this.binaryType);
      this._sender = new Sender(socket, this._extensions);
      this._ultron = new Ultron(socket);
      this._socket = socket;
  
      this._ultron.on('close', this._finalize);
      this._ultron.on('error', this._finalize);
      this._ultron.on('end', this._finalize);
  
      if (head.length > 0) socket.unshift(head);
  
      this._ultron.on('data', (data) => this._receiver.add(data));
  
      this._receiver.onmessage = (data) => this.emit('message', data);
      this._receiver.onping = (data) => {
        this.pong(data, !this._isServer, constants.NOOP);
        this.emit('ping', data);
      };
      this._receiver.onpong = (data) => this.emit('pong', data);
      this._receiver.onclose = (code, reason) => {
        this._closeFrameReceived = true;
        this._closeMessage = reason;
        this._closeCode = code;
  
        if (this._finalized) return;
  
        if (code === 1005) this.close();
        else this.close(code, reason);
      };
      this._receiver.onerror = (error, code) => {
        this._closeMessage = '';
        this._closeCode = code;
  
        //
        // Ensure that the error is emitted even if `WebSocket#finalize()` has
        // already been called.
        //
        this.readyState = WebSocket.CLOSING;
        this.emit('error', error);
        this.finalize(true);
      };
  
      this.readyState = WebSocket.OPEN;
      this.emit('open');
    }
  
    /**
     * Clean up and release internal resources.
     *
     * @param {(Boolean|Error)} error Indicates whether or not an error occurred
     * @private
     */
    finalize (error) {
      if (this._finalized) return;
  
      this.readyState = WebSocket.CLOSING;
      this._finalized = true;
  
      if (typeof error === 'object') this.emit('error', error);
      if (!this._socket) return this.emitClose();
  
      clearTimeout(this._closeTimer);
      this._closeTimer = null;
  
      this._ultron.destroy();
      this._ultron = null;
  
      this._socket.on('error', constants.NOOP);
  
      if (!error) this._socket.end();
      else this._socket.destroy();
  
      this._socket = null;
      this._sender = null;
  
      this._receiver.cleanup(() => this.emitClose());
      this._receiver = null;
    }
  
    /**
     * Emit the `close` event.
     *
     * @private
     */
    emitClose () {
      this.readyState = WebSocket.CLOSED;
  
      this.emit('close', this._closeCode, this._closeMessage);
  
      if (this._extensions[PerMessageDeflate.extensionName]) {
        this._extensions[PerMessageDeflate.extensionName].cleanup();
      }
  
      this.removeAllListeners();
    }
  
    /**
     * Start a closing handshake.
     *
     *            +----------+     +-----------+   +----------+
     *     + - - -|ws.close()|---->|close frame|-->|ws.close()|- - - -
     *            +----------+     +-----------+   +----------+       |
     *     |      +----------+     +-----------+         |
     *            |ws.close()|<----|close frame|<--------+            |
     *            +----------+     +-----------+         |
     *  CLOSING         |              +---+             |         CLOSING
     *                  |          +---|fin|<------------+
     *     |            |          |   +---+                          |
     *                  |          |   +---+      +-------------+
     *     |            +----------+-->|fin|----->|ws.finalize()| - - +
     *                             |   +---+      +-------------+
     *     |     +-------------+   |
     *      - - -|ws.finalize()|<--+
     *           +-------------+
     *
     * @param {Number} code Status code explaining why the connection is closing
     * @param {String} data A string explaining why the connection is closing
     * @public
     */
    close (code, data) {
      if (this.readyState === WebSocket.CLOSED) return;
      if (this.readyState === WebSocket.CONNECTING) {
        this._req.abort();
        this.finalize(
          new Error('WebSocket was closed before the connection was established')
        );
        return;
      }
  
      if (this.readyState === WebSocket.CLOSING) {
        if (this._closeFrameSent && this._closeFrameReceived) this._socket.end();
        return;
      }
  
      this.readyState = WebSocket.CLOSING;
      this._sender.close(code, data, !this._isServer, (err) => {
        //
        // This error is handled by the `'error'` listener on the socket. We only
        // want to know if the close frame has been sent here.
        //
        if (err) return;
  
        this._closeFrameSent = true;
  
        if (!this._finalized) {
          if (this._closeFrameReceived) this._socket.end();
  
          //
          // Ensure that the connection is cleaned up even when the closing
          // handshake fails.
          //
          this._closeTimer = setTimeout(this._finalize, closeTimeout, true);
        }
      });
    }
  
    /**
     * Send a ping.
     *
     * @param {*} data The data to send
     * @param {Boolean} mask Indicates whether or not to mask `data`
     * @param {Function} cb Callback which is executed when the ping is sent
     * @public
     */
    ping (data, mask, cb) {
      if (typeof data === 'function') {
        cb = data;
        data = mask = undefined;
      } else if (typeof mask === 'function') {
        cb = mask;
        mask = undefined;
      }
  
      if (this.readyState !== WebSocket.OPEN) {
        const err = new Error(
          `WebSocket is not open: readyState ${this.readyState} ` +
            `(${readyStates[this.readyState]})`
        );
  
        if (cb) return cb(err);
        throw err;
      }
  
      if (typeof data === 'number') data = data.toString();
      if (mask === undefined) mask = !this._isServer;
      this._sender.ping(data || constants.EMPTY_BUFFER, mask, cb);
    }
  
    /**
     * Send a pong.
     *
     * @param {*} data The data to send
     * @param {Boolean} mask Indicates whether or not to mask `data`
     * @param {Function} cb Callback which is executed when the pong is sent
     * @public
     */
    pong (data, mask, cb) {
      if (typeof data === 'function') {
        cb = data;
        data = mask = undefined;
      } else if (typeof mask === 'function') {
        cb = mask;
        mask = undefined;
      }
  
      if (this.readyState !== WebSocket.OPEN) {
        const err = new Error(
          `WebSocket is not open: readyState ${this.readyState} ` +
            `(${readyStates[this.readyState]})`
        );
  
        if (cb) return cb(err);
        throw err;
      }
  
      if (typeof data === 'number') data = data.toString();
      if (mask === undefined) mask = !this._isServer;
      this._sender.pong(data || constants.EMPTY_BUFFER, mask, cb);
    }
  
    /**
     * Send a data message.
     *
     * @param {*} data The message to send
     * @param {Object} options Options object
     * @param {Boolean} options.compress Specifies whether or not to compress `data`
     * @param {Boolean} options.binary Specifies whether `data` is binary or text
     * @param {Boolean} options.fin Specifies whether the fragment is the last one
     * @param {Boolean} options.mask Specifies whether or not to mask `data`
     * @param {Function} cb Callback which is executed when data is written out
     * @public
     */
    send (data, options, cb) {
      if (typeof options === 'function') {
        cb = options;
        options = {};
      }
  
      if (this.readyState !== WebSocket.OPEN) {
        const err = new Error(
          `WebSocket is not open: readyState ${this.readyState} ` +
            `(${readyStates[this.readyState]})`
        );
  
        if (cb) return cb(err);
        throw err;
      }
  
      if (typeof data === 'number') data = data.toString();
  
      const opts = Object.assign({
        binary: typeof data !== 'string',
        mask: !this._isServer,
        compress: true,
        fin: true
      }, options);
  
      if (!this._extensions[PerMessageDeflate.extensionName]) {
        opts.compress = false;
      }
  
      this._sender.send(data || constants.EMPTY_BUFFER, opts, cb);
    }
  
    /**
     * Forcibly close the connection.
     *
     * @public
     */
    terminate () {
      if (this.readyState === WebSocket.CLOSED) return;
      if (this.readyState === WebSocket.CONNECTING) {
        this._req.abort();
        this.finalize(
          new Error('WebSocket was closed before the connection was established')
        );
        return;
      }
  
      this.finalize(true);
    }
  }
  
  readyStates.forEach((readyState, i) => {
    WebSocket[readyStates[i]] = i;
  });
  
  //
  // Add the `onopen`, `onerror`, `onclose`, and `onmessage` attributes.
  // See https://html.spec.whatwg.org/multipage/comms.html#the-websocket-interface
  //
  ['open', 'error', 'close', 'message'].forEach((method) => {
    Object.defineProperty(WebSocket.prototype, `on${method}`, {
      /**
       * Return the listener of the event.
       *
       * @return {(Function|undefined)} The event listener or `undefined`
       * @public
       */
      get () {
        const listeners = this.listeners(method);
        for (var i = 0; i < listeners.length; i++) {
          if (listeners[i]._listener) return listeners[i]._listener;
        }
      },
      /**
       * Add a listener for the event.
       *
       * @param {Function} listener The listener to add
       * @public
       */
      set (listener) {
        const listeners = this.listeners(method);
        for (var i = 0; i < listeners.length; i++) {
          //
          // Remove only the listeners added via `addEventListener`.
          //
          if (listeners[i]._listener) this.removeListener(method, listeners[i]);
        }
        this.addEventListener(method, listener);
      }
    });
  });
  
  WebSocket.prototype.addEventListener = EventTarget.addEventListener;
  WebSocket.prototype.removeEventListener = EventTarget.removeEventListener;
  
  module.exports = WebSocket;
  
  /**
   * Initialize a WebSocket client.
   *
   * @param {String} address The URL to which to connect
   * @param {String[]} protocols The list of subprotocols
   * @param {Object} options Connection options
   * @param {String} options.protocol Value of the `Sec-WebSocket-Protocol` header
   * @param {(Boolean|Object)} options.perMessageDeflate Enable/disable permessage-deflate
   * @param {Number} options.handshakeTimeout Timeout in milliseconds for the handshake request
   * @param {String} options.localAddress Local interface to bind for network connections
   * @param {Number} options.protocolVersion Value of the `Sec-WebSocket-Version` header
   * @param {Object} options.headers An object containing request headers
   * @param {String} options.origin Value of the `Origin` or `Sec-WebSocket-Origin` header
   * @param {http.Agent} options.agent Use the specified Agent
   * @param {String} options.host Value of the `Host` header
   * @param {Number} options.family IP address family to use during hostname lookup (4 or 6).
   * @param {Function} options.checkServerIdentity A function to validate the server hostname
   * @param {Boolean} options.rejectUnauthorized Verify or not the server certificate
   * @param {String} options.passphrase The passphrase for the private key or pfx
   * @param {String} options.ciphers The ciphers to use or exclude
   * @param {String} options.ecdhCurve The curves for ECDH key agreement to use or exclude
   * @param {(String|String[]|Buffer|Buffer[])} options.cert The certificate key
   * @param {(String|String[]|Buffer|Buffer[])} options.key The private key
   * @param {(String|Buffer)} options.pfx The private key, certificate, and CA certs
   * @param {(String|String[]|Buffer|Buffer[])} options.ca Trusted certificates
   * @private
   */
  function initAsClient (address, protocols, options) {
    options = Object.assign({
      protocolVersion: protocolVersions[1],
      protocol: protocols.join(','),
      perMessageDeflate: true,
      handshakeTimeout: null,
      localAddress: null,
      headers: null,
      family: null,
      origin: null,
      agent: null,
      host: null,
  
      //
      // SSL options.
      //
      checkServerIdentity: null,
      rejectUnauthorized: null,
      passphrase: null,
      ciphers: null,
      ecdhCurve: null,
      cert: null,
      key: null,
      pfx: null,
      ca: null
    }, options);
  
    if (protocolVersions.indexOf(options.protocolVersion) === -1) {
      throw new RangeError(
        `Unsupported protocol version: ${options.protocolVersion} ` +
          `(supported versions: ${protocolVersions.join(', ')})`
      );
    }
  
    this._isServer = false;
    this.url = address;
  
    const serverUrl = url.parse(address);
    const isUnixSocket = serverUrl.protocol === 'ws+unix:';
  
    if (!serverUrl.host && (!isUnixSocket || !serverUrl.path)) {
      throw new Error(`Invalid URL: ${address}`);
    }
  
    const isSecure = serverUrl.protocol === 'wss:' || serverUrl.protocol === 'https:';
    const key = crypto.randomBytes(16).toString('base64');
    const httpObj = isSecure ? https : http;
    var perMessageDeflate;
  
    const requestOptions = {
      port: serverUrl.port || (isSecure ? 443 : 80),
      host: serverUrl.hostname,
      path: '/',
      headers: {
        'Sec-WebSocket-Version': options.protocolVersion,
        'Sec-WebSocket-Key': key,
        'Connection': 'Upgrade',
        'Upgrade': 'websocket'
      }
    };
  
    if (options.headers) Object.assign(requestOptions.headers, options.headers);
    if (options.perMessageDeflate) {
      perMessageDeflate = new PerMessageDeflate(
        options.perMessageDeflate !== true ? options.perMessageDeflate : {},
        false
      );
      requestOptions.headers['Sec-WebSocket-Extensions'] = extension.format({
        [PerMessageDeflate.extensionName]: perMessageDeflate.offer()
      });
    }
    if (options.protocol) {
      requestOptions.headers['Sec-WebSocket-Protocol'] = options.protocol;
    }
    if (options.origin) {
      if (options.protocolVersion < 13) {
        requestOptions.headers['Sec-WebSocket-Origin'] = options.origin;
      } else {
        requestOptions.headers.Origin = options.origin;
      }
    }
    if (options.host) requestOptions.headers.Host = options.host;
    if (serverUrl.auth) requestOptions.auth = serverUrl.auth;
  
    if (options.localAddress) requestOptions.localAddress = options.localAddress;
    if (options.family) requestOptions.family = options.family;
  
    if (isUnixSocket) {
      const parts = serverUrl.path.split(':');
  
      requestOptions.socketPath = parts[0];
      requestOptions.path = parts[1];
    } else if (serverUrl.path) {
      //
      // Make sure that path starts with `/`.
      //
      if (serverUrl.path.charAt(0) !== '/') {
        requestOptions.path = `/${serverUrl.path}`;
      } else {
        requestOptions.path = serverUrl.path;
      }
    }
  
    var agent = options.agent;
  
    //
    // A custom agent is required for these options.
    //
    if (
      options.rejectUnauthorized != null ||
      options.checkServerIdentity ||
      options.passphrase ||
      options.ciphers ||
      options.ecdhCurve ||
      options.cert ||
      options.key ||
      options.pfx ||
      options.ca
    ) {
      if (options.passphrase) requestOptions.passphrase = options.passphrase;
      if (options.ciphers) requestOptions.ciphers = options.ciphers;
      if (options.ecdhCurve) requestOptions.ecdhCurve = options.ecdhCurve;
      if (options.cert) requestOptions.cert = options.cert;
      if (options.key) requestOptions.key = options.key;
      if (options.pfx) requestOptions.pfx = options.pfx;
      if (options.ca) requestOptions.ca = options.ca;
      if (options.checkServerIdentity) {
        requestOptions.checkServerIdentity = options.checkServerIdentity;
      }
      if (options.rejectUnauthorized != null) {
        requestOptions.rejectUnauthorized = options.rejectUnauthorized;
      }
  
      if (!agent) agent = new httpObj.Agent(requestOptions);
    }
  
    if (agent) requestOptions.agent = agent;
  
    this._req = httpObj.get(requestOptions);
  
    if (options.handshakeTimeout) {
      this._req.setTimeout(options.handshakeTimeout, () => {
        this._req.abort();
        this.finalize(new Error('Opening handshake has timed out'));
      });
    }
  
    this._req.on('error', (error) => {
      if (this._req.aborted) return;
  
      this._req = null;
      this.finalize(error);
    });
  
    this._req.on('response', (res) => {
      if (!this.emit('unexpected-response', this._req, res)) {
        this._req.abort();
        this.finalize(new Error(`Unexpected server response: ${res.statusCode}`));
      }
    });
  
    this._req.on('upgrade', (res, socket, head) => {
      this.emit('upgrade', res);
  
      //
      // The user may have closed the connection from a listener of the `upgrade`
      // event.
      //
      if (this.readyState !== WebSocket.CONNECTING) return;
  
      this._req = null;
  
      const digest = crypto.createHash('sha1')
        .update(key + constants.GUID, 'binary')
        .digest('base64');
  
      if (res.headers['sec-websocket-accept'] !== digest) {
        socket.destroy();
        return this.finalize(new Error('Invalid Sec-WebSocket-Accept header'));
      }
  
      const serverProt = res.headers['sec-websocket-protocol'];
      const protList = (options.protocol || '').split(/, */);
      var protError;
  
      if (!options.protocol && serverProt) {
        protError = 'Server sent a subprotocol but none was requested';
      } else if (options.protocol && !serverProt) {
        protError = 'Server sent no subprotocol';
      } else if (serverProt && protList.indexOf(serverProt) === -1) {
        protError = 'Server sent an invalid subprotocol';
      }
  
      if (protError) {
        socket.destroy();
        return this.finalize(new Error(protError));
      }
  
      if (serverProt) this.protocol = serverProt;
  
      if (perMessageDeflate) {
        try {
          const extensions = extension.parse(
            res.headers['sec-websocket-extensions']
          );
  
          if (extensions[PerMessageDeflate.extensionName]) {
            perMessageDeflate.accept(
              extensions[PerMessageDeflate.extensionName]
            );
            this._extensions[PerMessageDeflate.extensionName] = perMessageDeflate;
          }
        } catch (err) {
          socket.destroy();
          this.finalize(new Error('Invalid Sec-WebSocket-Extensions header'));
          return;
        }
      }
  
      this.setSocket(socket, head, 0);
    });
  }
  