platform.js

/*!
 * Platform.js v1.0.0 <http://mths.be/platform>
 * Copyright 2010-2012 John-David Dalton <http://allyoucanleet.com/>
 * Available under MIT license <http://mths.be/mit>
 */
;(function(window) {
  'use strict';

  /** Backup possible window/global object */
  var oldWin = window;

  /** Detect free variable `exports` */
  var freeExports = typeof exports == 'object' && exports;

  /** Detect free variable `global` */
  var freeGlobal = typeof global == 'object' && global &&
    (global == global.global ? (window = global) : global);

  /** Opera regexp */
  var reOpera = /Opera/;

  /** Used to resolve a value's internal [[Class]] */
  var toString = {}.toString;

  /** Detect Java environment */
  var java = /Java/.test(getClassOf(window.java)) && window.java;

  /** A character to represent alpha */
  var alpha = java ? 'a' : '\u03b1';

  /** A character to represent beta */
  var beta = java ? 'b' : '\u03b2';

  /** Browser document object */
  var doc = window.document || {};

  /** Used to check for own properties of an object */
  var hasOwnProperty = {}.hasOwnProperty;

  /** Browser navigator object */
  var nav = window.navigator || {};

  /**
   * Detect Opera browser
   * http://www.howtocreate.co.uk/operaStuff/operaObject.html
   * http://dev.opera.com/articles/view/opera-mini-web-content-authoring-guidelines/#operamini
   */
  var opera = window.operamini || window.opera;

  /** Opera [[Class]] */
  var operaClass = reOpera.test(operaClass = getClassOf(opera)) ? operaClass : (opera = null);

  /** Possible global object */
  var thisBinding = this;

  /** Browser user agent string */
  var userAgent = nav.userAgent || '';

  /*--------------------------------------------------------------------------*/

  /**
   * Capitalizes a string value.
   *
   * @private
   * @param {String} string The string to capitalize.
   * @returns {String} The capitalized string.
   */
  function capitalize(string) {
    string = String(string);
    return string.charAt(0).toUpperCase() + string.slice(1);
  }

  /**
   * An iteration utility for arrays and objects.
   *
   * @private
   * @param {Array|Object} object The object to iterate over.
   * @param {Function} callback The function called per iteration.
   */
  function each(object, callback) {
    var index = -1,
        length = object.length;

    if (length == length >>> 0) {
      while (++index < length) {
        callback(object[index], index, object);
      }
    } else {
      forOwn(object, callback);
    }
  }

  /**
   * Trim and conditionally capitalize string values.
   *
   * @private
   * @param {String} string The string to format.
   * @returns {String} The formatted string.
   */
  function format(string) {
    string = trim(string);
    return /^(?:webOS|i(?:OS|P))/.test(string)
      ? string
      : capitalize(string);
  }

  /**
   * Iterates over an object's own properties, executing the `callback` for each.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {Function} callback The function executed per own property.
   */
  function forOwn(object, callback) {
    for (var key in object) {
      hasKey(object, key) && callback(object[key], key, object);
    }
  }

  /**
   * Gets the internal [[Class]] of a value.
   *
   * @private
   * @param {Mixed} value The value.
   * @returns {String} The [[Class]].
   */
  function getClassOf(value) {
    return value == null
      ? capitalize(value)
      : toString.call(value).slice(8, -1);
  }

  /**
   * Checks if an object has the specified key as a direct property.
   *
   * @private
   * @param {Object} object The object to check.
   * @param {String} key The key to check for.
   * @returns {Boolean} Returns `true` if key is a direct property, else `false`.
   */
  function hasKey() {
    // lazy define for others (not as accurate)
    hasKey = function(object, key) {
      var parent = object != null && (object.constructor || Object).prototype;
      return !!parent && key in Object(object) && !(key in parent && object[key] === parent[key]);
    };
    // for modern browsers
    if (getClassOf(hasOwnProperty) == 'Function') {
      hasKey = function(object, key) {
        return object != null && hasOwnProperty.call(object, key);
      };
    }
    // for Safari 2
    else if ({}.__proto__ == Object.prototype) {
      hasKey = function(object, key) {
        var result = false;
        if (object != null) {
          object = Object(object);
          object.__proto__ = [object.__proto__, object.__proto__ = null, result = key in object][0];
        }
        return result;
      };
    }
    return hasKey.apply(this, arguments);
  }

  /**
   * Host objects can return type values that are different from their actual
   * data type. The objects we are concerned with usually return non-primitive
   * types of object, function, or unknown.
   *
   * @private
   * @param {Mixed} object The owner of the property.
   * @param {String} property The property to check.
   * @returns {Boolean} Returns `true` if the property value is a non-primitive, else `false`.
   */
  function isHostType(object, property) {
    var type = object != null ? typeof object[property] : 'number';
    return !/^(?:boolean|number|string|undefined)$/.test(type) &&
      (type == 'object' ? !!object[property] : true);
  }

  /**
   * Prepares a string for use in a RegExp constructor by making hyphens and
   * spaces optional.
   *
   * @private
   * @param {String} string The string to qualify.
   * @returns {String} The qualified string.
   */
  function qualify(string) {
    return String(string).replace(/([ -])(?!$)/g, '$1?');
  }

  /**
   * A bare-bones` Array#reduce` like utility function.
   *
   * @private
   * @param {Array} array The array to iterate over.
   * @param {Function} callback The function called per iteration.
   * @param {Mixed} accumulator Initial value of the accumulator.
   * @returns {Mixed} The accumulator.
   */
  function reduce(array, callback) {
    var accumulator = null;
    each(array, function(value, index) {
      accumulator = callback(accumulator, value, index, array);
    });
    return accumulator;
  }

  /**
   * Removes leading and trailing whitespace from a string.
   *
   * @private
   * @param {String} string The string to trim.
   * @returns {String} The trimmed string.
   */
  function trim(string) {
    return String(string).replace(/^ +| +$/g, '');
  }

  /*--------------------------------------------------------------------------*/

  /**
   * Creates a new platform object.
   *
   * @memberOf platform
   * @param {String} [ua = navigator.userAgent] The user agent string.
   * @returns {Object} A platform object.
   */
  function parse(ua) {

    ua || (ua = userAgent);

    /** Temporary variable used over the script's lifetime */
    var data;

    /** The CPU architecture */
    var arch = ua;

    /** Platform description array */
    var description = [];

    /** Platform alpha/beta indicator */
    var prerelease = null;

    /** A flag to indicate that environment features should be used to resolve the platform */
    var useFeatures = ua == userAgent;

    /** The browser/environment version */
    var version = useFeatures && opera && typeof opera.version == 'function' && opera.version();

    /* Detectable layout engines (order is important) */
    var layout = getLayout([
      { 'label': 'WebKit', 'pattern': 'AppleWebKit' },
      'iCab',
      'Presto',
      'NetFront',
      'Tasman',
      'Trident',
      'KHTML',
      'Gecko'
    ]);

    /* Detectable browser names (order is important) */
    var name = getName([
      'Adobe AIR',
      'Arora',
      'Avant Browser',
      'Camino',
      'Epiphany',
      'Fennec',
      'Flock',
      'Galeon',
      'GreenBrowser',
      'iCab',
      'Iceweasel',
      'Iron',
      'K-Meleon',
      'Konqueror',
      'Lunascape',
      'Maxthon',
      'Midori',
      'Nook Browser',
      'PhantomJS',
      'Raven',
      'Rekonq',
      'RockMelt',
      'SeaMonkey',
      { 'label': 'Silk', 'pattern': '(?:Cloud9|Silk-Accelerated)' },
      'Sleipnir',
      'SlimBrowser',
      'Sunrise',
      'Swiftfox',
      'WebPositive',
      'Opera Mini',
      'Opera',
      'Chrome',
      { 'label': 'Chrome Mobile', 'pattern': '(?:CriOS|CrMo)' },
      { 'label': 'Firefox', 'pattern': '(?:Firefox|Minefield)' },
      { 'label': 'IE', 'pattern': 'MSIE' },
      'Safari'
    ]);

    /* Detectable products (order is important) */
    var product = getProduct([
      'BlackBerry',
      { 'label': 'Galaxy S', 'pattern': 'GT-I9000' },
      { 'label': 'Galaxy S2', 'pattern': 'GT-I9100' },
      'Google TV',
      'iPad',
      'iPod',
      'iPhone',
      'Kindle',
      { 'label': 'Kindle Fire', 'pattern': '(?:Cloud9|Silk-Accelerated)' },
      'Nook',
      'PlayBook',
      'PlayStation Vita',
      'TouchPad',
      'Transformer',
      'Xoom'
    ]);

    /* Detectable manufacturers */
    var manufacturer = getManufacturer({
      'Apple': { 'iPad': 1, 'iPhone': 1, 'iPod': 1 },
      'Amazon': { 'Kindle': 1, 'Kindle Fire': 1 },
      'Asus': { 'Transformer': 1 },
      'Barnes & Noble': { 'Nook': 1 },
      'BlackBerry': { 'PlayBook': 1 },
      'Google': { 'Google TV': 1 },
      'HP': { 'TouchPad': 1 },
      'LG': { },
      'Motorola': { 'Xoom': 1 },
      'Nokia': { },
      'Samsung': { 'Galaxy S': 1, 'Galaxy S2': 1 },
      'Sony': { 'PlayStation Vita': 1 }
    });

    /* Detectable OSes (order is important) */
    var os = getOS([
      'Android',
      'CentOS',
      'Debian',
      'Fedora',
      'FreeBSD',
      'Gentoo',
      'Haiku',
      'Kubuntu',
      'Linux Mint',
      'Red Hat',
      'SuSE',
      'Ubuntu',
      'Xubuntu',
      'Cygwin',
      'Symbian OS',
      'hpwOS',
      'webOS ',
      'webOS',
      'Tablet OS',
      'Linux',
      'Mac OS X',
      'Macintosh',
      'Mac',
      'Windows 98;',
      'Windows '
    ]);

    /*------------------------------------------------------------------------*/

    /**
     * Picks the layout engine from an array of guesses.
     *
     * @private
     * @param {Array} guesses An array of guesses.
     * @returns {String|Null} The detected layout engine.
     */
    function getLayout(guesses) {
      return reduce(guesses, function(result, guess) {
        return result || RegExp('\\b' + (
          guess.pattern || qualify(guess)
        ) + '\\b', 'i').exec(ua) && (guess.label || guess);
      });
    }

    /**
     * Picks the manufacturer from an array of guesses.
     *
     * @private
     * @param {Array} guesses An array of guesses.
     * @returns {String|Null} The detected manufacturer.
     */
    function getManufacturer(guesses) {
      return reduce(guesses, function(result, value, key) {
        // lookup the manufacturer by product or scan the UA for the manufacturer
        return result || (
          value[product] ||
          value[0/*Opera 9.25 fix*/, /^[a-z]+(?: +[a-z]+\b)*/i.exec(product)] ||
          RegExp('\\b' + (key.pattern || qualify(key)) + '(?:\\b|\\w*\\d)', 'i').exec(ua)
        ) && (key.label || key);
      });
    }

    /**
     * Picks the browser name from an array of guesses.
     *
     * @private
     * @param {Array} guesses An array of guesses.
     * @returns {String|Null} The detected browser name.
     */
    function getName(guesses) {
      return reduce(guesses, function(result, guess) {
        return result || RegExp('\\b' + (
          guess.pattern || qualify(guess)
        ) + '\\b', 'i').exec(ua) && (guess.label || guess);
      });
    }

    /**
     * Picks the OS name from an array of guesses.
     *
     * @private
     * @param {Array} guesses An array of guesses.
     * @returns {String|Null} The detected OS name.
     */
    function getOS(guesses) {
      return reduce(guesses, function(result, guess) {
        var pattern = guess.pattern || qualify(guess);
        if (!result && (result =
            RegExp('\\b' + pattern + '(?:/[\\d.]+|[ \\w.]*)', 'i').exec(ua))) {
          // platform tokens defined at
          // http://msdn.microsoft.com/en-us/library/ms537503(VS.85).aspx
          // http://web.archive.org/web/20081122053950/http://msdn.microsoft.com/en-us/library/ms537503(VS.85).aspx
          data = {
            '6.2':  '8',
            '6.1':  'Server 2008 R2 / 7',
            '6.0':  'Server 2008 / Vista',
            '5.2':  'Server 2003 / XP 64-bit',
            '5.1':  'XP',
            '5.01': '2000 SP1',
            '5.0':  '2000',
            '4.0':  'NT',
            '4.90': 'ME'
          };
          // detect Windows version from platform tokens
          if (/^Win/i.test(result) &&
              (data = data[0/*Opera 9.25 fix*/, /[\d.]+$/.exec(result)])) {
            result = 'Windows ' + data;
          }
          // correct character case and cleanup
          result = format(String(result)
            .replace(RegExp(pattern, 'i'), guess.label || guess)
            .replace(/ ce$/i, ' CE')
            .replace(/hpw/i, 'web')
            .replace(/Macintosh/, 'Mac OS')
            .replace(/_PowerPC/i, ' OS')
            .replace(/(OS X) [^ \d]+/i, '$1')
            .replace(/\/(\d)/, ' $1')
            .replace(/_/g, '.')
            .replace(/(?: BePC|[ .]*fc[ \d.]+)$/i, '')
            .replace(/x86\.64/gi, 'x86_64')
            .split(' on ')[0]);
        }
        return result;
      });
    }

    /**
     * Picks the product name from an array of guesses.
     *
     * @private
     * @param {Array} guesses An array of guesses.
     * @returns {String|Null} The detected product name.
     */
    function getProduct(guesses) {
      return reduce(guesses, function(result, guess) {
        var pattern = guess.pattern || qualify(guess);
        if (!result && (result =
              RegExp('\\b' + pattern + ' *\\d+[.\\w_]*', 'i').exec(ua) ||
              RegExp('\\b' + pattern + '(?:; *(?:[a-z]+[_-])?[a-z]+\\d+|[^ ();-]*)', 'i').exec(ua)
            )) {
          // split by forward slash and append product version if needed
          if ((result = String(guess.label || result).split('/'))[1] && !/[\d.]+/.test(result[0])) {
            result[0] += ' ' + result[1];
          }
          // correct character case and cleanup
          guess = guess.label || guess;
          result = format(result[0]
            .replace(RegExp(pattern, 'i'), guess)
            .replace(RegExp('; *(?:' + guess + '[_-])?', 'i'), ' ')
            .replace(RegExp('(' + guess + ')(\\w)', 'i'), '$1 $2'));
        }
        return result;
      });
    }

    /**
     * Resolves the version using an array of UA patterns.
     *
     * @private
     * @param {Array} patterns An array of UA patterns.
     * @returns {String|Null} The detected version.
     */
    function getVersion(patterns) {
      return reduce(patterns, function(result, pattern) {
        return result || (RegExp(pattern +
          '(?:-[\\d.]+/|(?: for [\\w-]+)?[ /-])([\\d.]+[^ ();/_-]*)', 'i').exec(ua) || 0)[1] || null;
      });
    }

    /*------------------------------------------------------------------------*/

    /**
     * Returns `platform.description` when the platform object is coerced to a string.
     *
     * @name toString
     * @memberOf platform
     * @returns {String} Returns `platform.description` if available, else an empty string.
     */
    function toStringPlatform() {
      return this.description || '';
    }

    /*------------------------------------------------------------------------*/

    // convert layout to an array so we can add extra details
    layout && (layout = [layout]);

    // detect product names that contain their manufacturer's name
    if (manufacturer && !product) {
      product = getProduct([manufacturer]);
    }
    // clean up Google TV
    if ((data = /Google TV/.exec(product))) {
      product = data[0];
    }
    // detect simulators
    if (/\bSimulator\b/i.test(ua)) {
      product = (product ? product + ' ' : '') + 'Simulator';
    }
    // detect iOS
    if (/^iP/.test(product)) {
      name || (name = 'Safari');
      os = 'iOS' + ((data = / OS ([\d_]+)/i.exec(ua))
        ? ' ' + data[1].replace(/_/g, '.')
        : '');
    }
    // detect Kubuntu
    else if (name == 'Konqueror' && !/buntu/i.test(os)) {
      os = 'Kubuntu';
    }
    // detect Android browsers
    else if (manufacturer && manufacturer != 'Google' &&
        /Chrome|Vita/.test(name + ';' + product)) {
      name = 'Android Browser';
      os = /Android/.test(os) ? os : 'Android';
    }
    // detect false positives for Firefox/Safari
    else if (!name || (data = !/\bMinefield\b/i.test(ua) && /Firefox|Safari/.exec(name))) {
      // escape the `/` for Firefox 1
      if (name && !product && /[\/,]|^[^(]+?\)/.test(ua.slice(ua.indexOf(data + '/') + 8))) {
        // clear name of false positives
        name = null;
      }
      // reassign a generic name
      if ((data = product || manufacturer || os) &&
          (product || manufacturer || /Android|Symbian OS|Tablet OS|webOS/.test(os))) {
        name = /[a-z]+(?: Hat)?/i.exec(/Android/.test(os) ? os : data) + ' Browser';
      }
    }
    // detect non-Opera versions (order is important)
    if (!version) {
      version = getVersion([
        '(?:Cloud9|CriOS|CrMo|Opera ?Mini|Raven|Silk(?!/[\\d.]+$))',
        'Version',
        qualify(name),
        '(?:Firefox|Minefield|NetFront)'
      ]);
    }
    // detect stubborn layout engines
    if (layout == 'iCab' && parseFloat(version) > 3) {
      layout = ['WebKit'];
    } else if (data =
        /Opera/.test(name) && 'Presto' ||
        /\b(?:Midori|Nook|Safari)\b/i.test(ua) && 'WebKit' ||
        !layout && /\bMSIE\b/i.test(ua) && (/^Mac/.test(os) ? 'Tasman' : 'Trident')) {
      layout = [data];
    }
    // leverage environment features
    if (useFeatures) {
      // detect server-side environments
      // Rhino has a global function while others have a global object
      if (isHostType(window, 'global')) {
        if (java) {
          data = java.lang.System;
          arch = data.getProperty('os.arch');
          os = os || data.getProperty('os.name') + ' ' + data.getProperty('os.version');
        }
        if (typeof exports == 'object' && exports) {
          // if `thisBinding` is the [ModuleScope]
          if (thisBinding == oldWin && typeof system == 'object' && (data = [system])[0]) {
            os || (os = data[0].os || null);
            try {
              data[1] = require('ringo/engine').version;
              version = data[1].join('.');
              name = 'RingoJS';
            } catch(e) {
              if (data[0].global == freeGlobal) {
                name = 'Narwhal';
              }
            }
          } else if (typeof process == 'object' && (data = process)) {
            name = 'Node.js';
            arch = data.arch;
            os = data.platform;
            version = /[\d.]+/.exec(data.version)[0];
          }
        } else if (getClassOf(window.environment) == 'Environment') {
          name = 'Rhino';
        }
      }
      // detect Adobe AIR
      else if (getClassOf(data = window.runtime) == 'ScriptBridgingProxyObject') {
        name = 'Adobe AIR';
        os = data.flash.system.Capabilities.os;
      }
      // detect PhantomJS
      else if (getClassOf(data = window.phantom) == 'RuntimeObject') {
        name = 'PhantomJS';
        version = (data = data.version || null) && (data.major + '.' + data.minor + '.' + data.patch);
      }
      // detect IE compatibility modes
      else if (typeof doc.documentMode == 'number' && (data = /\bTrident\/(\d+)/i.exec(ua))) {
        // we're in compatibility mode when the Trident version + 4 doesn't
        // equal the document mode
        version = [version, doc.documentMode];
        if ((data = +data[1] + 4) != version[1]) {
          description.push('IE ' + version[1] + ' mode');
          layout[1] = '';
          version[1] = data;
        }
        version = name == 'IE' ? String(version[1].toFixed(1)) : version[0];
      }
      os = os && format(os);
    }
    // detect prerelease phases
    if (version && (data =
        /(?:[ab]|dp|pre|[ab]\d+pre)(?:\d+\+?)?$/i.exec(version) ||
        /(?:alpha|beta)(?: ?\d)?/i.exec(ua + ';' + (useFeatures && nav.appMinorVersion)) ||
        /\bMinefield\b/i.test(ua) && 'a')) {
      prerelease = /b/i.test(data) ? 'beta' : 'alpha';
      version = version.replace(RegExp(data + '\\+?$'), '') +
        (prerelease == 'beta' ? beta : alpha) + (/\d+\+?/.exec(data) || '');
    }
    // rename code name "Fennec"
    if (name == 'Fennec') {
      name = 'Firefox Mobile';
    }
    // obscure Maxthon's unreliable version
    else if (name == 'Maxthon' && version) {
      version = version.replace(/\.[\d.]+/, '.x');
    }
    // detect Silk desktop/accelerated modes
    else if (name == 'Silk') {
      if (!/Mobi/i.test(ua)) {
        os = 'Android';
        description.unshift('desktop mode');
      }
      if (/Accelerated *= *true/i.test(ua)) {
        description.unshift('accelerated');
      }
    }
    // detect Windows Phone desktop mode
    else if (name == 'IE' && (data = (/; *(?:XBLWP|ZuneWP)(\d+)/i.exec(ua) || 0)[1])) {
      name += ' Mobile';
      os = 'Windows Phone OS ' + data + '.x';
      description.unshift('desktop mode');
    }
    // add mobile postfix
    else if ((name == 'IE' || name && !product && !/Browser|Mobi/.test(name)) &&
        (os == 'Windows CE' || /Mobi/i.test(ua))) {
      name += ' Mobile';
    }
    // detect IE platform preview
    else if (name == 'IE' && useFeatures && typeof external == 'object' && !external) {
      description.unshift('platform preview');
    }
    // detect BlackBerry OS version
    // http://docs.blackberry.com/en/developers/deliverables/18169/HTTP_headers_sent_by_BB_Browser_1234911_11.jsp
    else if (/BlackBerry/.test(product) && (data =
        (RegExp(product.replace(/ +/g, ' *') + '/([.\\d]+)', 'i').exec(ua) || 0)[1] ||
        version)) {
      os = 'Device Software ' + data;
      version = null;
    }
    // detect Opera identifying/masking itself as another browser
    // http://www.opera.com/support/kb/view/843/
    else if (this != forOwn && (
          (useFeatures && opera) ||
          (/Opera/.test(name) && /\b(?:MSIE|Firefox)\b/i.test(ua)) ||
          (name == 'Firefox' && /OS X (?:\d+\.){2,}/.test(os)) ||
          (name == 'IE' && (
            (os && !/^Win/.test(os) && version > 5.5) ||
            /Windows XP/.test(os) && version > 8 ||
            version == 8 && !/Trident/.test(ua)
          ))
        ) && !reOpera.test(data = parse.call(forOwn, ua.replace(reOpera, '') + ';')) && data.name) {

      // when "indentifying", the UA contains both Opera and the other browser's name
      data = 'ing as ' + data.name + ((data = data.version) ? ' ' + data : '');
      if (reOpera.test(name)) {
        if (/IE/.test(data) && os == 'Mac OS') {
          os = null;
        }
        data = 'identify' + data;
      }
      // when "masking", the UA contains only the other browser's name
      else {
        data = 'mask' + data;
        if (operaClass) {
          name = format(operaClass.replace(/([a-z])([A-Z])/g, '$1 $2'));
        } else {
          name = 'Opera';
        }
        if (/IE/.test(data)) {
          os = null;
        }
        if (!useFeatures) {
          version = null;
        }
      }
      layout = ['Presto'];
      description.push(data);
    }
    // detect WebKit Nightly and approximate Chrome/Safari versions
    if ((data = (/\bAppleWebKit\/([\d.]+\+?)/i.exec(ua) || 0)[1])) {
      // correct build for numeric comparison
      // (e.g. "532.5" becomes "532.05")
      data = [parseFloat(data.replace(/\.(\d)$/, '.0$1')), data];
      // nightly builds are postfixed with a `+`
      if (name == 'Safari' && data[1].slice(-1) == '+') {
        name = 'WebKit Nightly';
        prerelease = 'alpha';
        version = data[1].slice(0, -1);
      }
      // clear incorrect browser versions
      else if (version == data[1] ||
          version == (/\bSafari\/([\d.]+\+?)/i.exec(ua) || 0)[1]) {
        version = null;
      }
      // use the full Chrome version when available
      data = [data[0], (/\bChrome\/([\d.]+)/i.exec(ua) || 0)[1]];

      // detect JavaScriptCore
      // http://stackoverflow.com/questions/6768474/how-can-i-detect-which-javascript-engine-v8-or-jsc-is-used-at-runtime-in-androi
      if (!useFeatures || (/internal|\n/i.test(toString.toString()) && !data[1])) {
        layout[1] = 'like Safari';
        data = (data = data[0], data < 400 ? 1 : data < 500 ? 2 : data < 526 ? 3 : data < 533 ? 4 : data < 534 ? '4+' : data < 535 ? 5 : '5');
      } else {
        layout[1] = 'like Chrome';
        data = data[1] || (data = data[0], data < 530 ? 1 : data < 532 ? 2 : data < 532.05 ? 3 : data < 533 ? 4 : data < 534.03 ? 5 : data < 534.07 ? 6 : data < 534.10 ? 7 : data < 534.13 ? 8 : data < 534.16 ? 9 : data < 534.24 ? 10 : data < 534.30 ? 11 : data < 535.01 ? 12 : data < 535.02 ? '13+' : data < 535.07 ? 15 : data < 535.11 ? 16 : data < 535.19 ? 17 : data < 536.05 ? 18 : data < 536.10 ? 19 : data < 537.01 ? 20 : '21');
      }
      // add the postfix of ".x" or "+" for approximate versions
      layout[1] += ' ' + (data += typeof data == 'number' ? '.x' : /[.+]/.test(data) ? '' : '+');
      // obscure version for some Safari 1-2 releases
      if (name == 'Safari' && (!version || parseInt(version) > 45)) {
        version = data;
      }
    }
    // detect Opera desktop modes
    if (name == 'Opera' &&  (data = /(?:zbov|zvav)$/.exec(os))) {
      name += ' ';
      description.unshift('desktop mode');
      if (data == 'zvav') {
        name += 'Mini';
        version = null;
      } else {
        name += 'Mobile';
      }
    }
    // detect Chrome desktop mode
    else if (name == 'Safari' && /Chrome/.exec(layout[1])) {
      description.unshift('desktop mode');
      name = 'Chrome Mobile';
      version = null;

      if (/Mac OS X/.test(os)) {
        manufacturer = 'Apple';
        os = 'iOS 4.3+';
      } else {
        os = null;
      }
    }
    // strip incorrect OS versions
    if (version && version.indexOf(data = /[\d.]+$/.exec(os)) == 0 &&
        ua.indexOf('/' + data + '-') > -1) {
      os = trim(os.replace(data, ''));
    }
    // add layout engine
    if (layout && !/Avant|Nook/.test(name) && (
        /Browser|Lunascape|Maxthon/.test(name) ||
        /^(?:Adobe|Arora|Midori|Phantom|Rekonq|Rock|Sleipnir|Web)/.test(name) && layout[1])) {
      // don't add layout details to description if they are falsey
      (data = layout[layout.length - 1]) && description.push(data);
    }
    // combine contextual information
    if (description.length) {
      description = ['(' + description.join('; ') + ')'];
    }
    // append manufacturer
    if (manufacturer && product && product.indexOf(manufacturer) < 0) {
      description.push('on ' + manufacturer);
    }
    // append product
    if (product) {
      description.push((/^on /.test(description[description.length -1]) ? '' : 'on ') + product);
    }
    // parse OS into an object
    if (os) {
      data = / ([\d.+]+)$/.exec(os);
      os = {
        'architecture': 32,
        'family': data ? os.replace(data[0], '') : os,
        'version': data ? data[1] : null,
        'toString': function() {
          var version = this.version;
          return this.family + (version ? ' ' + version : '') + (this.architecture == 64 ? ' 64-bit' : '');
        }
      };
    }
    // add browser/OS architecture
    if ((data = / (?:AMD|IA|Win|WOW|x86_|x)64\b/i.exec(arch)) && !/\bi686\b/i.test(arch)) {
      if (os) {
        os.architecture = 64;
        os.family = os.family.replace(data, '');
      }
      if (name && (/WOW64/i.test(ua) ||
          (useFeatures && /\w(?:86|32)$/.test(nav.cpuClass || nav.platform)))) {
        description.unshift('32-bit');
      }
    }

    ua || (ua = null);

    /*------------------------------------------------------------------------*/

    /**
     * The platform object.
     *
     * @name platform
     * @type Object
     */
    return {

      /**
       * The browser/environment version.
       *
       * @memberOf platform
       * @type String|Null
       */
      'version': name && version && (description.unshift(version), version),

      /**
       * The name of the browser/environment.
       *
       * @memberOf platform
       * @type String|Null
       */
      'name': name && (description.unshift(name), name),

      /**
       * The name of the operating system.
       *
       * @memberOf platform
       * @type Object
       */
      'os': os
        ? (name &&
            !(os == String(os).split(' ')[0] && (os == name.split(' ')[0] || product)) &&
              description.push(product ? '(' + os + ')' : 'on ' + os), os)
        : {

          /**
           * The CPU architecture the OS is built for.
           *
           * @memberOf platform.os
           * @type String|Null
           */
          'architecture': null,

          /**
           * The family of the OS.
           *
           * @memberOf platform.os
           * @type String|Null
           */
          'family': null,

          /**
           * The version of the OS.
           *
           * @memberOf platform.os
           * @type String|Null
           */
          'version': null,

          /**
           * Returns the OS string.
           *
           * @memberOf platform.os
           * @returns {String} The OS string.
           */
          'toString': function() { return 'null'; }
        },

      /**
       * The platform description.
       *
       * @memberOf platform
       * @type String|Null
       */
      'description': description.length ? description.join(' ') : ua,

      /**
       * The name of the browser layout engine.
       *
       * @memberOf platform
       * @type String|Null
       */
      'layout': layout && layout[0],

      /**
       * The name of the product's manufacturer.
       *
       * @memberOf platform
       * @type String|Null
       */
      'manufacturer': manufacturer,

      /**
       * The alpha/beta release indicator.
       *
       * @memberOf platform
       * @type String|Null
       */
      'prerelease': prerelease,

      /**
       * The name of the product hosting the browser.
       *
       * @memberOf platform
       * @type String|Null
       */
      'product': product,

      /**
       * The browser's user agent string.
       *
       * @memberOf platform
       * @type String|Null
       */
      'ua': ua,

      // parses a user agent string into a platform object
      'parse': parse,

      // returns the platform description
      'toString': toStringPlatform
    };
  }

  /*--------------------------------------------------------------------------*/

  // expose platform
  // some AMD build optimizers, like r.js, check for specific condition patterns like the following:
  if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) {
    // define as an anonymous module so, through path mapping, it can be aliased
    define(function() {
      return parse();
    });
  }
  // check for `exports` after `define` in case a build optimizer adds an `exports` object
  else if (freeExports) {
    // in Narwhal, Node.js, or RingoJS
    forOwn(parse(), function(value, key) {
      freeExports[key] = value;
    });
  }
  // in a browser or Rhino
  else {
    // use square bracket notation so Closure Compiler won't munge `platform`
    // http://code.google.com/closure/compiler/docs/api-tutorial3.html#export
    window['platform'] = parse();
  }
}(this));