text: /*!
   * ws: a node.js websocket client
   * Copyright(c) 2011 Einar Otto Stangvik <einaros@gmail.com>
   * MIT Licensed
   */
  
  var events = require('events')
    , util = require('util')
    , EventEmitter = events.EventEmitter;
  
  /**
   * Hixie Sender implementation
   */
  
  function Sender(socket) {
    this.socket = socket;
    this.continuationFrame = false;
    this.isClosed = false;
  }
  
  module.exports = Sender;
  
  /**
   * Inherits from EventEmitter.
   */
  
  util.inherits(Sender, events.EventEmitter);
  
  /**
   * Frames and writes data.
   *
   * @api public
   */
  
  Sender.prototype.send = function(data, options, cb) {
    if (this.isClosed) return;
    if (options && options.binary) {
      this.error('hixie websockets do not support binary');
      return;
    }
  
    var isString = typeof data == 'string'
      , length = isString ? Buffer.byteLength(data) : data.length
      , writeStartMarker = this.continuationFrame == false
      , writeEndMarker = !options || !(typeof options.fin != 'undefined' && !options.fin)
      , buffer = new Buffer((writeStartMarker ? 1 : 0) + length + (writeEndMarker ? 1 : 0))
      , offset = writeStartMarker ? 1 : 0;
  
    if (writeStartMarker) buffer.write('\x00', 'binary');
  
    if (isString) buffer.write(data, offset, 'utf8');
    else data.copy(buffer, offset, 0);
  
    if (writeEndMarker) {
      buffer.write('\xff', offset + length, 'binary');
      this.continuationFrame = false;
    }
    else this.continuationFrame = true;
  
    try {
      return this.socket.write(buffer, 'binary', cb);
    } catch (e) {
      this.error(e.toString());
    }
  }
  
  /**
   * Sends a close instruction to the remote party.
   *
   * @api public
   */
  
  Sender.prototype.close = function(code, data, mask, cb) {
    if (this.isClosed) return;
    this.isClosed = true;
    try {
      if (this.continuationFrame) this.socket.write(new Buffer([0xff], 'binary'));
      return this.socket.write(new Buffer([0xff, 0x00]), 'binary', cb);
    } catch (e) {
      this.error(e.toString());
    }
  }
  
  /**
   * Sends a ping message to the remote party. Not available for hixie.
   *
   * @api public
   */
  
  Sender.prototype.ping = function(data, options) {}
  
  /**
   * Sends a pong message to the remote party. Not available for hixie.
   *
   * @api public
   */
  
  Sender.prototype.pong = function(data, options) {}
  
  /**
   * Handles an error
   *
   * @api private
   */
  
  Sender.prototype.error = function (reason) {
    this.emit('error', reason);
    return this;
  }
  