/*
* fingerprintJS 0.3 - Fast browser fingerprint library
* https://github.com/Valve/fingerprintjs
* Copyright (c) 2013 Valentin Vasilyev (iamvalentin@gmail.com)
* Licensed under the MIT (http://www.opensource.org/licenses/mit-license.php) license.
*/
/*jslint browser: true, indent: 2 */
(function(scope) {
  'use strict';

  var Fingerprint = function(hasher){
    var nativeForEach = Array.prototype.forEach;
    var nativeMap = Array.prototype.map;
    this.each = function(obj, iterator, context) {
      if(obj === null) return;
      if(nativeForEach && obj.forEach === nativeForEach) {
        obj.forEach(iterator, context);
      } else if (obj.length === +obj.length) {
        for (var i = 0, l = obj.length; i < l; i++) {
          if (iterator.call(context, obj[i], i, obj) === {}) return;
        }
      } else {
        for (var key in obj) {
          if (obj.hasOwnProperty(key)) {
            if (iterator.call(context, obj[key], key, obj) === {}) return;
          }
        }
      }
    };
    this.map = function(obj, iterator, context) {
      var results = [];
      if (obj == null) return results;
      if (nativeMap && obj.map === nativeMap) return obj.map(iterator, context);
      this.each(obj, function(value, index, list) {
        results[results.length] = iterator.call(context, value, index, list);
      });
      return results;
    };

    if(hasher){
      this.hasher = hasher;
    }
  }

  Fingerprint.prototype = {

    get: function(){
      var keys = [];
      keys.push(navigator.userAgent);
      keys.push(navigator.language);
      keys.push(screen.colorDepth);
      keys.push(new Date().getTimezoneOffset());
      keys.push(!!window.sessionStorage);
      keys.push(!!window.localStorage);
      var pluginsString = this.map(navigator.plugins, function(p){
        var mimeTypes = this.map(p, function(mt){
          return [mt.type, mt.suffixes].join('~');
        }).join(',');
        return [p.name, p.description, mimeTypes].join('::');
      }, this).join(';');
      keys.push(pluginsString);
      if(this.hasher){
        return this.hasher(keys.join('###'), 31);
      } else {
        return this.murmurhash3_32_gc(keys.join('###'), 31);
      }
    },

    /**
     * JS Implementation of MurmurHash3 (r136) (as of May 20, 2011)
     * 
     * @author <a href="mailto:gary.court@gmail.com">Gary Court</a>
     * @see http://github.com/garycourt/murmurhash-js
     * @author <a href="mailto:aappleby@gmail.com">Austin Appleby</a>
     * @see http://sites.google.com/site/murmurhash/
     * 
     * @param {string} key ASCII only
     * @param {number} seed Positive integer only
     * @return {number} 32-bit positive integer hash 
     */

    murmurhash3_32_gc: function(key, seed) {
      var remainder, bytes, h1, h1b, c1, c1b, c2, c2b, k1, i;
      
      remainder = key.length & 3; // key.length % 4
      bytes = key.length - remainder;
      h1 = seed;
      c1 = 0xcc9e2d51;
      c2 = 0x1b873593;
      i = 0;
      
      while (i < bytes) {
          k1 = 
            ((key.charCodeAt(i) & 0xff)) |
            ((key.charCodeAt(++i) & 0xff) << 8) |
            ((key.charCodeAt(++i) & 0xff) << 16) |
            ((key.charCodeAt(++i) & 0xff) << 24);
        ++i;
        
        k1 = ((((k1 & 0xffff) * c1) + ((((k1 >>> 16) * c1) & 0xffff) << 16))) & 0xffffffff;
        k1 = (k1 << 15) | (k1 >>> 17);
        k1 = ((((k1 & 0xffff) * c2) + ((((k1 >>> 16) * c2) & 0xffff) << 16))) & 0xffffffff;

        h1 ^= k1;
            h1 = (h1 << 13) | (h1 >>> 19);
        h1b = ((((h1 & 0xffff) * 5) + ((((h1 >>> 16) * 5) & 0xffff) << 16))) & 0xffffffff;
        h1 = (((h1b & 0xffff) + 0x6b64) + ((((h1b >>> 16) + 0xe654) & 0xffff) << 16));
      }
      
      k1 = 0;
      
      switch (remainder) {
        case 3: k1 ^= (key.charCodeAt(i + 2) & 0xff) << 16;
        case 2: k1 ^= (key.charCodeAt(i + 1) & 0xff) << 8;
        case 1: k1 ^= (key.charCodeAt(i) & 0xff);
        
        k1 = (((k1 & 0xffff) * c1) + ((((k1 >>> 16) * c1) & 0xffff) << 16)) & 0xffffffff;
        k1 = (k1 << 15) | (k1 >>> 17);
        k1 = (((k1 & 0xffff) * c2) + ((((k1 >>> 16) * c2) & 0xffff) << 16)) & 0xffffffff;
        h1 ^= k1;
      }
      
      h1 ^= key.length;

      h1 ^= h1 >>> 16;
      h1 = (((h1 & 0xffff) * 0x85ebca6b) + ((((h1 >>> 16) * 0x85ebca6b) & 0xffff) << 16)) & 0xffffffff;
      h1 ^= h1 >>> 13;
      h1 = ((((h1 & 0xffff) * 0xc2b2ae35) + ((((h1 >>> 16) * 0xc2b2ae35) & 0xffff) << 16))) & 0xffffffff;
      h1 ^= h1 >>> 16;

      return h1 >>> 0;
    }
  }

  scope.Fingerprint = Fingerprint;
})(window);
