/*  Prototype JavaScript framework,  version 1.6.0.2
 *  (c) 2005-2008 Sam Stephenson
 *
 *  Prototype is freely distributable under the terms of an MIT-style license.
 *  For details,  see the Prototype web site: http://www.prototypejs.org/
 *
 *--------------------------------------------------------------------------*/

var Prototype = {
  Version: '1.6.0.2', 

  Browser: {
    IE:     !!(window.attachEvent && !window.opera), 
    Opera:  !!window.opera, 
    WebKit: navigator.userAgent.indexOf('AppleWebKit/index.html') > -1, 
    Gecko:  navigator.userAgent.indexOf('Gecko') > -1 && navigator.userAgent.indexOf('KHTML') == -1, 
    MobileSafari: !!navigator.userAgent.match(/Apple.*Mobile.*Safari/)
  }, 

  BrowserFeatures: {
    XPath: !!document.evaluate, 
    ElementExtensions: !!window.HTMLElement, 
    SpecificElementExtensions:
      document.createElement('div').__proto__ &&
      document.createElement('div').__proto__ !==
        document.createElement('form').__proto__
  }, 

  ScriptFragment: '<script[^>]*>([\\S\\s]*?)<\/script>', 
  JSONFilter: /^\/\*-secure-([\s\S]*)\*\/\s*$/, 

  emptyFunction: function() { }, 
  K: function(x) { return x }
};

if (Prototype.Browser.MobileSafari)
  Prototype.BrowserFeatures.SpecificElementExtensions = false;


/* Based on Alex Arnell's inheritance implementation. */
var Class = {
  create: function() {
    var parent = null,  properties = $A(arguments);
    if (Object.isFunction(properties[0]))
      parent = properties.shift();

    function klass() {
      this.initialize.apply(this,  arguments);
    }

    Object.extend(klass,  Class.Methods);
    klass.superclass = parent;
    klass.subclasses = [];

    if (parent) {
      var subclass = function() { };
      subclass.prototype = parent.prototype;
      klass.prototype = new subclass;
      parent.subclasses.push(klass);
    }

    for (var i = 0; i < properties.length; i++)
      klass.addMethods(properties[i]);

    if (!klass.prototype.initialize)
      klass.prototype.initialize = Prototype.emptyFunction;

    klass.prototype.constructor = klass;

    return klass;
  }
};

Class.Methods = {
  addMethods: function(source) {
    var ancestor   = this.superclass && this.superclass.prototype;
    var properties = Object.keys(source);

    if (!Object.keys({ toString: true }).length)
      properties.push("toString",  "valueOf");

    for (var i = 0,  length = properties.length; i < length; i++) {
      var property = properties[i],  value = source[property];
      if (ancestor && Object.isFunction(value) &&
          value.argumentNames().first() == "$super") {
        var method = value,  value = Object.extend((function(m) {
          return function() { return ancestor[m].apply(this,  arguments) };
        })(property).wrap(method),  {
          valueOf:  function() { return method }, 
          toString: function() { return method.toString() }
        });
      }
      this.prototype[property] = value;
    }

    return this;
  }
};

var Abstract = { };

Object.extend = function(destination,  source) {
  for (var property in source)
    destination[property] = source[property];
  return destination;
};

Object.extend(Object,  {
  inspect: function(object) {
    try {
      if (Object.isUndefined(object)) return 'undefined';
      if (object === null) return 'null';
      return object.inspect ? object.inspect() : String(object);
    } catch (e) {
      if (e instanceof RangeError) return '...';
      throw e;
    }
  }, 

  toJSON: function(object) {
    var type = typeof object;
    switch (type) {
      case 'undefined':
      case 'function':
      case 'unknown': return;
      case 'boolean': return object.toString();
    }

    if (object === null) return 'null';
    if (object.toJSON) return object.toJSON();
    if (Object.isElement(object)) return;

    var results = [];
    for (var property in object) {
      var value = Object.toJSON(object[property]);
      if (!Object.isUndefined(value))
        results.push(property.toJSON() + ': ' + value);
    }

    return '{' + results.join(',  ') + '}';
  }, 

  toQueryString: function(object) {
    return $H(object).toQueryString();
  }, 

  toHTML: function(object) {
    return object && object.toHTML ? object.toHTML() : String.interpret(object);
  }, 

  keys: function(object) {
    var keys = [];
    for (var property in object)
      keys.push(property);
    return keys;
  }, 

  values: function(object) {
    var values = [];
    for (var property in object)
      values.push(object[property]);
    return values;
  }, 

  clone: function(object) {
    return Object.extend({ },  object);
  }, 

  isElement: function(object) {
    return object && object.nodeType == 1;
  }, 

  isArray: function(object) {
    return object != null && typeof object == "object" &&
      'splice' in object && 'join' in object;
  }, 

  isHash: function(object) {
    return object instanceof Hash;
  }, 

  isFunction: function(object) {
    return typeof object == "function";
  }, 

  isString: function(object) {
    return typeof object == "string";
  }, 

  isNumber: function(object) {
    return typeof object == "number";
  }, 

  isUndefined: function(object) {
    return typeof object == "undefined";
  }
});

Object.extend(Function.prototype,  {
  argumentNames: function() {
    var names = this.toString().match(/^[\s\(]*function[^(]*\((.*?)\)/)[1].split(", ").invoke("strip");
    return names.length == 1 && !names[0] ? [] : names;
  }, 

  bind: function() {
    if (arguments.length < 2 && Object.isUndefined(arguments[0])) return this;
    var __method = this,  args = $A(arguments),  object = args.shift();
    return function() {
      return __method.apply(object,  args.concat($A(arguments)));
    }
  }, 

  bindAsEventListener: function() {
    var __method = this,  args = $A(arguments),  object = args.shift();
    return function(event) {
      return __method.apply(object,  [event || window.event].concat(args));
    }
  }, 

  curry: function() {
    if (!arguments.length) return this;
    var __method = this,  args = $A(arguments);
    return function() {
      return __method.apply(this,  args.concat($A(arguments)));
    }
  }, 

  delay: function() {
    var __method = this,  args = $A(arguments),  timeout = args.shift() * 1000;
    return window.setTimeout(function() {
      return __method.apply(__method,  args);
    },  timeout);
  }, 

  wrap: function(wrapper) {
    var __method = this;
    return function() {
      return wrapper.apply(this,  [__method.bind(this)].concat($A(arguments)));
    }
  }, 

  methodize: function() {
    if (this._methodized) return this._methodized;
    var __method = this;
    return this._methodized = function() {
      return __method.apply(null,  [this].concat($A(arguments)));
    };
  }
});

Function.prototype.defer = Function.prototype.delay.curry(0.01);

Date.prototype.toJSON = function() {
  return '"' + this.getUTCFullYear() + '-' +
    (this.getUTCMonth() + 1).toPaddedString(2) + '-' +
    this.getUTCDate().toPaddedString(2) + 'T' +
    this.getUTCHours().toPaddedString(2) + ':' +
    this.getUTCMinutes().toPaddedString(2) + ':' +
    this.getUTCSeconds().toPaddedString(2) + 'Z"';
};

var Try = {
  these: function() {
    var returnValue;

    for (var i = 0,  length = arguments.length; i < length; i++) {
      var lambda = arguments[i];
      try {
        returnValue = lambda();
        break;
      } catch (e) { }
    }

    return returnValue;
  }
};

RegExp.prototype.match = RegExp.prototype.test;

RegExp.escape = function(str) {
  return String(str).replace(/([.*+?^=!:${}()|[\]\/\\])/g,  '\\$1');
};

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

var PeriodicalExecuter = Class.create({
  initialize: function(callback,  frequency) {
    this.callback = callback;
    this.frequency = frequency;
    this.currentlyExecuting = false;

    this.registerCallback();
  }, 

  registerCallback: function() {
    this.timer = setInterval(this.onTimerEvent.bind(this),  this.frequency * 1000);
  }, 

  execute: function() {
    this.callback(this);
  }, 

  stop: function() {
    if (!this.timer) return;
    clearInterval(this.timer);
    this.timer = null;
  }, 

  onTimerEvent: function() {
    if (!this.currentlyExecuting) {
      try {
        this.currentlyExecuting = true;
        this.execute();
      } finally {
        this.currentlyExecuting = false;
      }
    }
  }
});
Object.extend(String,  {
  interpret: function(value) {
    return value == null ? '' : String(value);
  }, 
  specialChar: {
    '\b': '\\b', 
    '\t': '\\t', 
    '\n': '\\n', 
    '\f': '\\f', 
    '\r': '\\r', 
    '\\': '\\\\'
  }
});

Object.extend(String.prototype,  {
  gsub: function(pattern,  replacement) {
    var result = '',  source = this,  match;
    replacement = arguments.callee.prepareReplacement(replacement);

    while (source.length > 0) {
      if (match = source.match(pattern)) {
        result += source.slice(0,  match.index);
        result += String.interpret(replacement(match));
        source  = source.slice(match.index + match[0].length);
      } else {
        result += source,  source = '';
      }
    }
    return result;
  }, 

  sub: function(pattern,  replacement,  count) {
    replacement = this.gsub.prepareReplacement(replacement);
    count = Object.isUndefined(count) ? 1 : count;

    return this.gsub(pattern,  function(match) {
      if (--count < 0) return match[0];
      return replacement(match);
    });
  }, 

  scan: function(pattern,  iterator) {
    this.gsub(pattern,  iterator);
    return String(this);
  }, 

  truncate: function(length,  truncation) {
    length = length || 30;
    truncation = Object.isUndefined(truncation) ? '...' : truncation;
    return this.length > length ?
      this.slice(0,  length - truncation.length) + truncation : String(this);
  }, 

  strip: function() {
    return this.replace(/^\s+/,  '').replace(/\s+$/,  '');
  }, 

  stripTags: function() {
    return this.replace(/<\/?[^>]+>/gi,  '');
  }, 

  stripScripts: function() {
    return this.replace(new RegExp(Prototype.ScriptFragment,  'img'),  '');
  }, 

  extractScripts: function() {
    var matchAll = new RegExp(Prototype.ScriptFragment,  'img');
    var matchOne = new RegExp(Prototype.ScriptFragment,  'im');
    return (this.match(matchAll) || []).map(function(scriptTag) {
      return (scriptTag.match(matchOne) || ['',  ''])[1];
    });
  }, 

  evalScripts: function() {
    return this.extractScripts().map(function(script) { return eval(script) });
  }, 

  escapeHTML: function() {
    var self = arguments.callee;
    self.text.data = this;
    return self.div.innerHTML;
  }, 

  unescapeHTML: function() {
    var div = new Element('div');
    div.innerHTML = this.stripTags();
    return div.childNodes[0] ? (div.childNodes.length > 1 ?
      $A(div.childNodes).inject('',  function(memo,  node) { return memo+node.nodeValue }) :
      div.childNodes[0].nodeValue) : '';
  }, 

  toQueryParams: function(separator) {
    var match = this.strip().match(/([^?#]*)(#.*)?$/);
    if (!match) return { };

    return match[1].split(separator || '&').inject({ },  function(hash,  pair) {
      if ((pair = pair.split('='))[0]) {
        var key = decodeURIComponent(pair.shift());
        var value = pair.length > 1 ? pair.join('=') : pair[0];
        if (value != undefined) value = decodeURIComponent(value);

        if (key in hash) {
          if (!Object.isArray(hash[key])) hash[key] = [hash[key]];
          hash[key].push(value);
        }
        else hash[key] = value;
      }
      return hash;
    });
  }, 

  toArray: function() {
    return this.split('');
  }, 

  succ: function() {
    return this.slice(0,  this.length - 1) +
      String.fromCharCode(this.charCodeAt(this.length - 1) + 1);
  }, 

  times: function(count) {
    return count < 1 ? '' : new Array(count + 1).join(this);
  }, 

  camelize: function() {
    var parts = this.split('-'),  len = parts.length;
    if (len == 1) return parts[0];

    var camelized = this.charAt(0) == '-'
      ? parts[0].charAt(0).toUpperCase() + parts[0].substring(1)
      : parts[0];

    for (var i = 1; i < len; i++)
      camelized += parts[i].charAt(0).toUpperCase() + parts[i].substring(1);

    return camelized;
  }, 

  capitalize: function() {
    return this.charAt(0).toUpperCase() + this.substring(1).toLowerCase();
  }, 

  underscore: function() {
    return this.gsub(/::/,  '/').gsub(/([A-Z]+)([A-Z][a-z])/, '#{1}_#{2}').gsub(/([a-z\d])([A-Z])/, '#{1}_#{2}').gsub(/-/, '_').toLowerCase();
  }, 

  dasherize: function() {
    return this.gsub(/_/, '-');
  }, 

  inspect: function(useDoubleQuotes) {
    var escapedString = this.gsub(/[\x00-\x1f\\]/,  function(match) {
      var character = String.specialChar[match[0]];
      return character ? character : '\\u00' + match[0].charCodeAt().toPaddedString(2,  16);
    });
    if (useDoubleQuotes) return '"' + escapedString.replace(/"/g,  '\\"') + '"';
    return "'" + escapedString.replace(/'/g,  '\\\'') + "'";
  }, 

  toJSON: function() {
    return this.inspect(true);
  }, 

  unfilterJSON: function(filter) {
    return this.sub(filter || Prototype.JSONFilter,  '#{1}');
  }, 

  isJSON: function() {
    var str = this;
    if (str.blank()) return false;
    str = this.replace(/\\./g,  '@').replace(/"[^"\\\n\r]*"/g,  '');
    return (/^[, :{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/).test(str);
  }, 

  evalJSON: function(sanitize) {
    var json = this.unfilterJSON();
    try {
      if (!sanitize || json.isJSON()) return eval('(' + json + ')');
    } catch (e) { }
    throw new SyntaxError('Badly formed JSON string: ' + this.inspect());
  }, 

  include: function(pattern) {
    return this.indexOf(pattern) > -1;
  }, 

  startsWith: function(pattern) {
    return this.indexOf(pattern) === 0;
  }, 

  endsWith: function(pattern) {
    var d = this.length - pattern.length;
    return d >= 0 && this.lastIndexOf(pattern) === d;
  }, 

  empty: function() {
    return this == '';
  }, 

  blank: function() {
    return /^\s*$/.test(this);
  }, 

  interpolate: function(object,  pattern) {
    return new Template(this,  pattern).evaluate(object);
  }
});

if (Prototype.Browser.WebKit || Prototype.Browser.IE) Object.extend(String.prototype,  {
  escapeHTML: function() {
    return this.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
  }, 
  unescapeHTML: function() {
    return this.replace(/&amp;/g, '&').replace(/&lt;/g, '<').replace(/&gt;/g, '>');
  }
});

String.prototype.gsub.prepareReplacement = function(replacement) {
  if (Object.isFunction(replacement)) return replacement;
  var template = new Template(replacement);
  return function(match) { return template.evaluate(match) };
};

String.prototype.parseQuery = String.prototype.toQueryParams;

Object.extend(String.prototype.escapeHTML,  {
  div:  document.createElement('div'), 
  text: document.createTextNode('')
});

with (String.prototype.escapeHTML) div.appendChild(text);

var Template = Class.create({
  initialize: function(template,  pattern) {
    this.template = template.toString();
    this.pattern = pattern || Template.Pattern;
  }, 

  evaluate: function(object) {
    if (Object.isFunction(object.toTemplateReplacements))
      object = object.toTemplateReplacements();

    return this.template.gsub(this.pattern,  function(match) {
      if (object == null) return '';

      var before = match[1] || '';
      if (before == '\\') return match[2];

      var ctx = object,  expr = match[3];
      var pattern = /^([^.[]+|\[((?:.*?[^\\])?)\])(\.|\[|$)/;
      match = pattern.exec(expr);
      if (match == null) return before;

      while (match != null) {
        var comp = match[1].startsWith('[') ? match[2].gsub('\\\\]',  ']') : match[1];
        ctx = ctx[comp];
        if (null == ctx || '' == match[3]) break;
        expr = expr.substring('[' == match[3] ? match[1].length : match[0].length);
        match = pattern.exec(expr);
      }

      return before + String.interpret(ctx);
    });
  }
});
Template.Pattern = /(^|.|\r|\n)(#\{(.*?)\})/;

var $break = { };

var Enumerable = {
  each: function(iterator,  context) {
    var index = 0;
    iterator = iterator.bind(context);
    try {
      this._each(function(value) {
        iterator(value,  index++);
      });
    } catch (e) {
      if (e != $break) throw e;
    }
    return this;
  }, 

  eachSlice: function(number,  iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var index = -number,  slices = [],  array = this.toArray();
    while ((index += number) < array.length)
      slices.push(array.slice(index,  index+number));
    return slices.collect(iterator,  context);
  }, 

  all: function(iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var result = true;
    this.each(function(value,  index) {
      result = result && !!iterator(value,  index);
      if (!result) throw $break;
    });
    return result;
  }, 

  any: function(iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var result = false;
    this.each(function(value,  index) {
      if (result = !!iterator(value,  index))
        throw $break;
    });
    return result;
  }, 

  collect: function(iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var results = [];
    this.each(function(value,  index) {
      results.push(iterator(value,  index));
    });
    return results;
  }, 

  detect: function(iterator,  context) {
    iterator = iterator.bind(context);
    var result;
    this.each(function(value,  index) {
      if (iterator(value,  index)) {
        result = value;
        throw $break;
      }
    });
    return result;
  }, 

  findAll: function(iterator,  context) {
    iterator = iterator.bind(context);
    var results = [];
    this.each(function(value,  index) {
      if (iterator(value,  index))
        results.push(value);
    });
    return results;
  }, 

  grep: function(filter,  iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var results = [];

    if (Object.isString(filter))
      filter = new RegExp(filter);

    this.each(function(value,  index) {
      if (filter.match(value))
        results.push(iterator(value,  index));
    });
    return results;
  }, 

  include: function(object) {
    if (Object.isFunction(this.indexOf))
      if (this.indexOf(object) != -1) return true;

    var found = false;
    this.each(function(value) {
      if (value == object) {
        found = true;
        throw $break;
      }
    });
    return found;
  }, 

  inGroupsOf: function(number,  fillWith) {
    fillWith = Object.isUndefined(fillWith) ? null : fillWith;
    return this.eachSlice(number,  function(slice) {
      while(slice.length < number) slice.push(fillWith);
      return slice;
    });
  }, 

  inject: function(memo,  iterator,  context) {
    iterator = iterator.bind(context);
    this.each(function(value,  index) {
      memo = iterator(memo,  value,  index);
    });
    return memo;
  }, 

  invoke: function(method) {
    var args = $A(arguments).slice(1);
    return this.map(function(value) {
      return value[method].apply(value,  args);
    });
  }, 

  max: function(iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var result;
    this.each(function(value,  index) {
      value = iterator(value,  index);
      if (result == null || value >= result)
        result = value;
    });
    return result;
  }, 

  min: function(iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var result;
    this.each(function(value,  index) {
      value = iterator(value,  index);
      if (result == null || value < result)
        result = value;
    });
    return result;
  }, 

  partition: function(iterator,  context) {
    iterator = iterator ? iterator.bind(context) : Prototype.K;
    var trues = [],  falses = [];
    this.each(function(value,  index) {
      (iterator(value,  index) ?
        trues : falses).push(value);
    });
    return [trues,  falses];
  }, 

  pluck: function(property) {
    var results = [];
    this.each(function(value) {
      results.push(value[property]);
    });
    return results;
  }, 

  reject: function(iterator,  context) {
    iterator = iterator.bind(context);
    var results = [];
    this.each(function(value,  index) {
      if (!iterator(value,  index))
        results.push(value);
    });
    return results;
  }, 

  sortBy: function(iterator,  context) {
    iterator = iterator.bind(context);
    return this.map(function(value,  index) {
      return {value: value,  criteria: iterator(value,  index)};
    }).sort(function(left,  right) {
      var a = left.criteria,  b = right.criteria;
      return a < b ? -1 : a > b ? 1 : 0;
    }).pluck('value');
  }, 

  toArray: function() {
    return this.map();
  }, 

  zip: function() {
    var iterator = Prototype.K,  args = $A(arguments);
    if (Object.isFunction(args.last()))
      iterator = args.pop();

    var collections = [this].concat(args).map($A);
    return this.map(function(value,  index) {
      return iterator(collections.pluck(index));
    });
  }, 

  size: function() {
    return this.toArray().length;
  }, 

  inspect: function() {
    return '#<Enumerable:' + this.toArray().inspect() + '>';
  }
};

Object.extend(Enumerable,  {
  map:     Enumerable.collect, 
  find:    Enumerable.detect, 
  select:  Enumerable.findAll, 
  filter:  Enumerable.findAll, 
  member:  Enumerable.include, 
  entries: Enumerable.toArray, 
  every:   Enumerable.all, 
  some:    Enumerable.any
});
function $A(iterable) {
  if (!iterable) return [];
  if (iterable.toArray) return iterable.toArray();
  var length = iterable.length || 0,  results = new Array(length);
  while (length--) results[length] = iterable[length];
  return results;
}

if (Prototype.Browser.WebKit) {
  $A = function(iterable) {
    if (!iterable) return [];
    if (!(Object.isFunction(iterable) && iterable == '[object NodeList]') &&
        iterable.toArray) return iterable.toArray();
    var length = iterable.length || 0,  results = new Array(length);
    while (length--) results[length] = iterable[length];
    return results;
  };
}

Array.from = $A;

Object.extend(Array.prototype,  Enumerable);

if (!Array.prototype._reverse) Array.prototype._reverse = Array.prototype.reverse;

Object.extend(Array.prototype,  {
  _each: function(iterator) {
    for (var i = 0,  length = this.length; i < length; i++)
      iterator(this[i]);
  }, 

  clear: function() {
    this.length = 0;
    return this;
  }, 

  first: function() {
    return this[0];
  }, 

  last: function() {
    return this[this.length - 1];
  }, 

  compact: function() {
    return this.select(function(value) {
      return value != null;
    });
  }, 

  flatten: function() {
    return this.inject([],  function(array,  value) {
      return array.concat(Object.isArray(value) ?
        value.flatten() : [value]);
    });
  }, 

  without: function() {
    var values = $A(arguments);
    return this.select(function(value) {
      return !values.include(value);
    });
  }, 

  reverse: function(inline) {
    return (inline !== false ? this : this.toArray())._reverse();
  }, 

  reduce: function() {
    return this.length > 1 ? this : this[0];
  }, 

  uniq: function(sorted) {
    return this.inject([],  function(array,  value,  index) {
      if (0 == index || (sorted ? array.last() != value : !array.include(value)))
        array.push(value);
      return array;
    });
  }, 

  intersect: function(array) {
    return this.uniq().findAll(function(item) {
      return array.detect(function(value) { return item === value });
    });
  }, 

  clone: function() {
    return [].concat(this);
  }, 

  size: function() {
    return this.length;
  }, 

  inspect: function() {
    return '[' + this.map(Object.inspect).join(',  ') + ']';
  }, 

  toJSON: function() {
    var results = [];
    this.each(function(object) {
      var value = Object.toJSON(object);
      if (!Object.isUndefined(value)) results.push(value);
    });
    return '[' + results.join(',  ') + ']';
  }
});

// use native browser JS 1.6 implementation if available
if (Object.isFunction(Array.prototype.forEach))
  Array.prototype._each = Array.prototype.forEach;

if (!Array.prototype.indexOf) Array.prototype.indexOf = function(item,  i) {
  i || (i = 0);
  var length = this.length;
  if (i < 0) i = length + i;
  for (; i < length; i++)
    if (this[i] === item) return i;
  return -1;
};

if (!Array.prototype.lastIndexOf) Array.prototype.lastIndexOf = function(item,  i) {
  i = isNaN(i) ? this.length : (i < 0 ? this.length + i : i) + 1;
  var n = this.slice(0,  i).reverse().indexOf(item);
  return (n < 0) ? n : i - n - 1;
};

Array.prototype.toArray = Array.prototype.clone;

function $w(string) {
  if (!Object.isString(string)) return [];
  string = string.strip();
  return string ? string.split(/\s+/) : [];
}

if (Prototype.Browser.Opera){
  Array.prototype.concat = function() {
    var array = [];
    for (var i = 0,  length = this.length; i < length; i++) array.push(this[i]);
    for (var i = 0,  length = arguments.length; i < length; i++) {
      if (Object.isArray(arguments[i])) {
        for (var j = 0,  arrayLength = arguments[i].length; j < arrayLength; j++)
          array.push(arguments[i][j]);
      } else {
        array.push(arguments[i]);
      }
    }
    return array;
  };
}
Object.extend(Number.prototype,  {
  toColorPart: function() {
    return this.toPaddedString(2,  16);
  }, 

  succ: function() {
    return this + 1;
  }, 

  times: function(iterator) {
    $R(0,  this,  true).each(iterator);
    return this;
  }, 

  toPaddedString: function(length,  radix) {
    var string = this.toString(radix || 10);
    return '0'.times(length - string.length) + string;
  }, 

  toJSON: function() {
    return isFinite(this) ? this.toString() : 'null';
  }
});

$w('abs round ceil floor').each(function(method){
  Number.prototype[method] = Math[method].methodize();
});
function $H(object) {
  return new Hash(object);
};

var Hash = Class.create(Enumerable,  (function() {

  function toQueryPair(key,  value) {
    if (Object.isUndefined(value)) return key;
    return key + '=' + encodeURIComponent(String.interpret(value));
  }

  return {
    initialize: function(object) {
      this._object = Object.isHash(object) ? object.toObject() : Object.clone(object);
    }, 

    _each: function(iterator) {
      for (var key in this._object) {
        var value = this._object[key],  pair = [key,  value];
        pair.key = key;
        pair.value = value;
        iterator(pair);
      }
    }, 

    set: function(key,  value) {
      return this._object[key] = value;
    }, 

    get: function(key) {
      return this._object[key];
    }, 

    unset: function(key) {
      var value = this._object[key];
      delete this._object[key];
      return value;
    }, 

    toObject: function() {
      return Object.clone(this._object);
    }, 

    keys: function() {
      return this.pluck('key');
    }, 

    values: function() {
      return this.pluck('value');
    }, 

    index: function(value) {
      var match = this.detect(function(pair) {
        return pair.value === value;
      });
      return match && match.key;
    }, 

    merge: function(object) {
      return this.clone().update(object);
    }, 

    update: function(object) {
      return new Hash(object).inject(this,  function(result,  pair) {
        result.set(pair.key,  pair.value);
        return result;
      });
    }, 

    toQueryString: function() {
      return this.map(function(pair) {
        var key = encodeURIComponent(pair.key),  values = pair.value;

        if (values && typeof values == 'object') {
          if (Object.isArray(values))
            return values.map(toQueryPair.curry(key)).join('&');
        }
        return toQueryPair(key,  values);
      }).join('&');
    }, 

    inspect: function() {
      return '#<Hash:{' + this.map(function(pair) {
        return pair.map(Object.inspect).join(': ');
      }).join(',  ') + '}>';
    }, 

    toJSON: function() {
      return Object.toJSON(this.toObject());
    }, 

    clone: function() {
      return new Hash(this);
    }
  }
})());

Hash.prototype.toTemplateReplacements = Hash.prototype.toObject;
Hash.from = $H;
var ObjectRange = Class.create(Enumerable,  {
  initialize: function(start,  end,  exclusive) {
    this.start = start;
    this.end = end;
    this.exclusive = exclusive;
  }, 

  _each: function(iterator) {
    var value = this.start;
    while (this.include(value)) {
      iterator(value);
      value = value.succ();
    }
  }, 

  include: function(value) {
    if (value < this.start)
      return false;
    if (this.exclusive)
      return value < this.end;
    return value <= this.end;
  }
});

var $R = function(start,  end,  exclusive) {
  return new ObjectRange(start,  end,  exclusive);
};

var Ajax = {
  getTransport: function() {
    return Try.these(
      function() {return new XMLHttpRequest()}, 
      function() {return new ActiveXObject('Msxml2.XMLHTTP')}, 
      function() {return new ActiveXObject('Microsoft.XMLHTTP')}
    ) || false;
  }, 

  activeRequestCount: 0
};

Ajax.Responders = {
  responders: [], 

  _each: function(iterator) {
    this.responders._each(iterator);
  }, 

  register: function(responder) {
    if (!this.include(responder))
      this.responders.push(responder);
  }, 

  unregister: function(responder) {
    this.responders = this.responders.without(responder);
  }, 

  dispatch: function(callback,  request,  transport,  json) {
    this.each(function(responder) {
      if (Object.isFunction(responder[callback])) {
        try {
          responder[callback].apply(responder,  [request,  transport,  json]);
        } catch (e) { }
      }
    });
  }
};

Object.extend(Ajax.Responders,  Enumerable);

Ajax.Responders.register({
  onCreate:   function() { Ajax.activeRequestCount++ }, 
  onComplete: function() { Ajax.activeRequestCount-- }
});

Ajax.Base = Class.create({
  initialize: function(options) {
    this.options = {
      method:       'post', 
      asynchronous: true, 
      contentType:  'application/x-www-form-urlencoded', 
      encoding:     'UTF-8', 
      parameters:   '', 
      evalJSON:     true, 
      evalJS:       true
    };
    Object.extend(this.options,  options || { });

    this.options.method = this.options.method.toLowerCase();

    if (Object.isString(this.options.parameters))
      this.options.parameters = this.options.parameters.toQueryParams();
    else if (Object.isHash(this.options.parameters))
      this.options.parameters = this.options.parameters.toObject();
  }
});

Ajax.Request = Class.create(Ajax.Base,  {
  _complete: false, 

  initialize: function($super,  url,  options) {
    $super(options);
    this.transport = Ajax.getTransport();
    this.request(url);
  }, 

  request: function(url) {
    this.url = url;
    this.method = this.options.method;
    var params = Object.clone(this.options.parameters);

    if (!['get',  'post'].include(this.method)) {
      // simulate other verbs over post
      params['_method'] = this.method;
      this.method = 'post';
    }

    this.parameters = params;

    if (params = Object.toQueryString(params)) {
      // when GET,  append parameters to URL
      if (this.method == 'get')
        this.url += (this.url.include('?') ? '&' : '?') + params;
      else if (/Konqueror|Safari|KHTML/.test(navigator.userAgent))
        params += '&_=';
    }

    try {
      var response = new Ajax.Response(this);
      if (this.options.onCreate) this.options.onCreate(response);
      Ajax.Responders.dispatch('onCreate',  this,  response);

      this.transport.open(this.method.toUpperCase(),  this.url, 
        this.options.asynchronous);

      if (this.options.asynchronous) this.respondToReadyState.bind(this).defer(1);

      this.transport.onreadystatechange = this.onStateChange.bind(this);
      this.setRequestHeaders();

      this.body = this.method == 'post' ? (this.options.postBody || params) : null;
      this.transport.send(this.body);

      /* Force Firefox to handle ready state 4 for synchronous requests */
      if (!this.options.asynchronous && this.transport.overrideMimeType)
        this.onStateChange();

    }
    catch (e) {
      this.dispatchException(e);
    }
  }, 

  onStateChange: function() {
    var readyState = this.transport.readyState;
    if (readyState > 1 && !((readyState == 4) && this._complete))
      this.respondToReadyState(this.transport.readyState);
  }, 

  setRequestHeaders: function() {
    var headers = {
      'X-Requested-With': 'XMLHttpRequest', 
      'X-Prototype-Version': Prototype.Version, 
      'Accept': 'text/javascript,  text/html,  application/xml,  text/xml,  */*'
    };

    if (this.method == 'post') {
      headers['Content-type'] = this.options.contentType +
        (this.options.encoding ? '; charset=' + this.options.encoding : '');

      /* Force "Connection: close" for older Mozilla browsers to work
       * around a bug where XMLHttpRequest sends an incorrect
       * Content-length header. See Mozilla Bugzilla #246651.
       */
      if (this.transport.overrideMimeType &&
          (navigator.userAgent.match(/Gecko\/(\d{4})/) || [0, 2005])[1] < 2005)
            headers['Connection'] = 'close';
    }

    // user-defined headers
    if (typeof this.options.requestHeaders == 'object') {
      var extras = this.options.requestHeaders;

      if (Object.isFunction(extras.push))
        for (var i = 0,  length = extras.length; i < length; i += 2)
          headers[extras[i]] = extras[i+1];
      else
        $H(extras).each(function(pair) { headers[pair.key] = pair.value });
    }

    for (var name in headers)
      this.transport.setRequestHeader(name,  headers[name]);
  }, 

  success: function() {
    var status = this.getStatus();
    return !status || (status >= 200 && status < 300);
  }, 

  getStatus: function() {
    try {
      return this.transport.status || 0;
    } catch (e) { return 0 }
  }, 

  respondToReadyState: function(readyState) {
    var state = Ajax.Request.Events[readyState],  response = new Ajax.Response(this);

    if (state == 'Complete') {
      try {
        this._complete = true;
        (this.options['on' + response.status]
         || this.options['on' + (this.success() ? 'Success' : 'Failure')]
         || Prototype.emptyFunction)(response,  response.headerJSON);
      } catch (e) {
        this.dispatchException(e);
      }

      var contentType = response.getHeader('Content-type');
      if (this.options.evalJS == 'force'
          || (this.options.evalJS && this.isSameOrigin() && contentType
          && contentType.match(/^\s*(text|application)\/(x-)?(java|ecma)script(;.*)?\s*$/i)))
        this.evalResponse();
    }

    try {
      (this.options['on' + state] || Prototype.emptyFunction)(response,  response.headerJSON);
      Ajax.Responders.dispatch('on' + state,  this,  response,  response.headerJSON);
    } catch (e) {
      this.dispatchException(e);
    }

    if (state == 'Complete') {
      // avoid memory leak in MSIE: clean up
      this.transport.onreadystatechange = Prototype.emptyFunction;
    }
  }, 

  isSameOrigin: function() {
    var m = this.url.match(/^\s*https?:\/\/[^\/]*/);
    return !m || (m[0] == '#{protocol}//#{domain}#{port}'.interpolate({
      protocol: location.protocol, 
      domain: document.domain, 
      port: location.port ? ':' + location.port : ''
    }));
  }, 

  getHeader: function(name) {
    try {
      return this.transport.getResponseHeader(name) || null;
    } catch (e) { return null }
  }, 

  evalResponse: function() {
    try {
      return eval((this.transport.responseText || '').unfilterJSON());
    } catch (e) {
      this.dispatchException(e);
    }
  }, 

  dispatchException: function(exception) {
    (this.options.onException || Prototype.emptyFunction)(this,  exception);
    Ajax.Responders.dispatch('onException',  this,  exception);
  }
});

Ajax.Request.Events =
  ['Uninitialized',  'Loading',  'Loaded',  'Informējoša brošūra',  'Complete'];

Ajax.Response = Class.create({
  initialize: function(request){
    this.request = request;
    var transport  = this.transport  = request.transport, 
        readyState = this.readyState = transport.readyState;

    if((readyState > 2 && !Prototype.Browser.IE) || readyState == 4) {
      this.status       = this.getStatus();
      this.statusText   = this.getStatusText();
      this.responseText = String.interpret(transport.responseText);
      this.headerJSON   = this._getHeaderJSON();
    }

    if(readyState == 4) {
      var xml = transport.responseXML;
      this.responseXML  = Object.isUndefined(xml) ? null : xml;
      this.responseJSON = this._getResponseJSON();
    }
  }, 

  status:      0, 
  statusText: '', 

  getStatus: Ajax.Request.prototype.getStatus, 

  getStatusText: function() {
    try {
      return this.transport.statusText || '';
    } catch (e) { return '' }
  }, 

  getHeader: Ajax.Request.prototype.getHeader, 

  getAllHeaders: function() {
    try {
      return this.getAllResponseHeaders();
    } catch (e) { return null }
  }, 

  getResponseHeader: function(name) {
    return this.transport.getResponseHeader(name);
  }, 

  getAllResponseHeaders: function() {
    return this.transport.getAllResponseHeaders();
  }, 

  _getHeaderJSON: function() {
    var json = this.getHeader('X-JSON');
    if (!json) return null;
    json = decodeURIComponent(escape(json));
    try {
      return json.evalJSON(this.request.options.sanitizeJSON ||
        !this.request.isSameOrigin());
    } catch (e) {
      this.request.dispatchException(e);
    }
  }, 

  _getResponseJSON: function() {
    var options = this.request.options;
    if (!options.evalJSON || (options.evalJSON != 'force' &&
      !(this.getHeader('Content-type') || '').include('application/json')) ||
        this.responseText.blank())
          return null;
    try {
      return this.responseText.evalJSON(options.sanitizeJSON ||
        !this.request.isSameOrigin());
    } catch (e) {
      this.request.dispatchException(e);
    }
  }
});

Ajax.Updater = Class.create(Ajax.Request,  {
  initialize: function($super,  container,  url,  options) {
    this.container = {
      success: (container.success || container), 
      failure: (container.failure || (container.success ? null : container))
    };

    options = Object.clone(options);
    var onComplete = options.onComplete;
    options.onComplete = (function(response,  json) {
      this.updateContent(response.responseText);
      if (Object.isFunction(onComplete)) onComplete(response,  json);
    }).bind(this);

    $super(url,  options);
  }, 

  updateContent: function(responseText) {
    var receiver = this.container[this.success() ? 'success' : 'failure'], 
        options = this.options;

    if (!options.evalScripts) responseText = responseText.stripScripts();

    if (receiver = $(receiver)) {
      if (options.insertion) {
        if (Object.isString(options.insertion)) {
          var insertion = { }; insertion[options.insertion] = responseText;
          receiver.insert(insertion);
        }
        else options.insertion(receiver,  responseText);
      }
      else receiver.update(responseText);
    }
  }
});

Ajax.PeriodicalUpdater = Class.create(Ajax.Base,  {
  initialize: function($super,  container,  url,  options) {
    $super(options);
    this.onComplete = this.options.onComplete;

    this.frequency = (this.options.frequency || 2);
    this.decay = (this.options.decay || 1);

    this.updater = { };
    this.container = container;
    this.url = url;

    this.start();
  }, 

  start: function() {
    this.options.onComplete = this.updateComplete.bind(this);
    this.onTimerEvent();
  }, 

  stop: function() {
    this.updater.options.onComplete = undefined;
    clearTimeout(this.timer);
    (this.onComplete || Prototype.emptyFunction).apply(this,  arguments);
  }, 

  updateComplete: function(response) {
    if (this.options.decay) {
      this.decay = (response.responseText == this.lastText ?
        this.decay * this.options.decay : 1);

      this.lastText = response.responseText;
    }
    this.timer = this.onTimerEvent.bind(this).delay(this.decay * this.frequency);
  }, 

  onTimerEvent: function() {
    this.updater = new Ajax.Updater(this.container,  this.url,  this.options);
  }
});
function $(element) {
  if (arguments.length > 1) {
    for (var i = 0,  elements = [],  length = arguments.length; i < length; i++)
      elements.push($(arguments[i]));
    return elements;
  }
  if (Object.isString(element))
    element = document.getElementById(element);
  return Element.extend(element);
}

if (Prototype.BrowserFeatures.XPath) {
  document._getElementsByXPath = function(expression,  parentElement) {
    var results = [];
    var query = document.evaluate(expression,  $(parentElement) || document, 
      null,  XPathResult.ORDERED_NODE_SNAPSHOT_TYPE,  null);
    for (var i = 0,  length = query.snapshotLength; i < length; i++)
      results.push(Element.extend(query.snapshotItem(i)));
    return results;
  };
}

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

if (!window.Node) var Node = { };

if (!Node.ELEMENT_NODE) {
  // DOM level 2 ECMAScript Language Binding
  Object.extend(Node,  {
    ELEMENT_NODE: 1, 
    ATTRIBUTE_NODE: 2, 
    TEXT_NODE: 3, 
    CDATA_SECTION_NODE: 4, 
    ENTITY_REFERENCE_NODE: 5, 
    ENTITY_NODE: 6, 
    PROCESSING_INSTRUCTION_NODE: 7, 
    COMMENT_NODE: 8, 
    DOCUMENT_NODE: 9, 
    DOCUMENT_TYPE_NODE: 10, 
    DOCUMENT_FRAGMENT_NODE: 11, 
    NOTATION_NODE: 12
  });
}

(function() {
  var element = this.Element;
  this.Element = function(tagName,  attributes) {
    attributes = attributes || { };
    tagName = tagName.toLowerCase();
    var cache = Element.cache;
    if (Prototype.Browser.IE && attributes.name) {
      tagName = '<' + tagName + ' name="' + attributes.name + '">';
      delete attributes.name;
      return Element.writeAttribute(document.createElement(tagName),  attributes);
    }
    if (!cache[tagName]) cache[tagName] = Element.extend(document.createElement(tagName));
    return Element.writeAttribute(cache[tagName].cloneNode(false),  attributes);
  };
  Object.extend(this.Element,  element || { });
}).call(window);

Element.cache = { };

Element.Methods = {
  visible: function(element) {
    return $(element).style.display != 'none';
  }, 

  toggle: function(element) {
    element = $(element);
    Element[Element.visible(element) ? 'hide' : 'show'](element);
    return element;
  }, 

  hide: function(element) {
    $(element).style.display = 'none';
    return element;
  }, 

  show: function(element) {
    $(element).style.display = '';
    return element;
  }, 

  remove: function(element) {
    element = $(element);
    element.parentNode.removeChild(element);
    return element;
  }, 

  update: function(element,  content) {
    element = $(element);
    if (content && content.toElement) content = content.toElement();
    if (Object.isElement(content)) return element.update().insert(content);
    content = Object.toHTML(content);
    element.innerHTML = content.stripScripts();
    content.evalScripts.bind(content).defer();
    return element;
  }, 

  replace: function(element,  content) {
    element = $(element);
    if (content && content.toElement) content = content.toElement();
    else if (!Object.isElement(content)) {
      content = Object.toHTML(content);
      var range = element.ownerDocument.createRange();
      range.selectNode(element);
      content.evalScripts.bind(content).defer();
      content = range.createContextualFragment(content.stripScripts());
    }
    element.parentNode.replaceChild(content,  element);
    return element;
  }, 

  insert: function(element,  insertions) {
    element = $(element);

    if (Object.isString(insertions) || Object.isNumber(insertions) ||
        Object.isElement(insertions) || (insertions && (insertions.toElement || insertions.toHTML)))
          insertions = {bottom:insertions};

    var content,  insert,  tagName,  childNodes;

    for (var position in insertions) {
      content  = insertions[position];
      position = position.toLowerCase();
      insert = Element._insertionTranslations[position];

      if (content && content.toElement) content = content.toElement();
      if (Object.isElement(content)) {
        insert(element,  content);
        continue;
      }

      content = Object.toHTML(content);

      tagName = ((position == 'before' || position == 'after')
        ? element.parentNode : element).tagName.toUpperCase();

      childNodes = Element._getContentFromAnonymousElement(tagName,  content.stripScripts());

      if (position == 'top' || position == 'after') childNodes.reverse();
      childNodes.each(insert.curry(element));

      content.evalScripts.bind(content).defer();
    }

    return element;
  }, 

  wrap: function(element,  wrapper,  attributes) {
    element = $(element);
    if (Object.isElement(wrapper))
      $(wrapper).writeAttribute(attributes || { });
    else if (Object.isString(wrapper)) wrapper = new Element(wrapper,  attributes);
    else wrapper = new Element('div',  wrapper);
    if (element.parentNode)
      element.parentNode.replaceChild(wrapper,  element);
    wrapper.appendChild(element);
    return wrapper;
  }, 

  inspect: function(element) {
    element = $(element);
    var result = '<' + element.tagName.toLowerCase();
    $H({'id': 'id',  'className': 'class'}).each(function(pair) {
      var property = pair.first(),  attribute = pair.last();
      var value = (element[property] || '').toString();
      if (value) result += ' ' + attribute + '=' + value.inspect(true);
    });
    return result + '>';
  }, 

  recursivelyCollect: function(element,  property) {
    element = $(element);
    var elements = [];
    while (element = element[property])
      if (element.nodeType == 1)
        elements.push(Element.extend(element));
    return elements;
  }, 

  ancestors: function(element) {
    return $(element).recursivelyCollect('parentNode');
  }, 

  descendants: function(element) {
    return $(element).select("*");
  }, 

  firstDescendant: function(element) {
    element = $(element).firstChild;
    while (element && element.nodeType != 1) element = element.nextSibling;
    return $(element);
  }, 

  immediateDescendants: function(element) {
    if (!(element = $(element).firstChild)) return [];
    while (element && element.nodeType != 1) element = element.nextSibling;
    if (element) return [element].concat($(element).nextSiblings());
    return [];
  }, 

  previousSiblings: function(element) {
    return $(element).recursivelyCollect('previousSibling');
  }, 

  nextSiblings: function(element) {
    return $(element).recursivelyCollect('nextSibling');
  }, 

  siblings: function(element) {
    element = $(element);
    return element.previousSiblings().reverse().concat(element.nextSiblings());
  }, 

  match: function(element,  selector) {
    if (Object.isString(selector))
      selector = new Selector(selector);
    return selector.match($(element));
  }, 

  up: function(element,  expression,  index) {
    element = $(element);
    if (arguments.length == 1) return $(element.parentNode);
    var ancestors = element.ancestors();
    return Object.isNumber(expression) ? ancestors[expression] :
      Selector.findElement(ancestors,  expression,  index);
  }, 

  down: function(element,  expression,  index) {
    element = $(element);
    if (arguments.length == 1) return element.firstDescendant();
    return Object.isNumber(expression) ? element.descendants()[expression] :
      element.select(expression)[index || 0];
  }, 

  previous: function(element,  expression,  index) {
    element = $(element);
    if (arguments.length == 1) return $(Selector.handlers.previousElementSibling(element));
    var previousSiblings = element.previousSiblings();
    return Object.isNumber(expression) ? previousSiblings[expression] :
      Selector.findElement(previousSiblings,  expression,  index);
  }, 

  next: function(element,  expression,  index) {
    element = $(element);
    if (arguments.length == 1) return $(Selector.handlers.nextElementSibling(element));
    var nextSiblings = element.nextSiblings();
    return Object.isNumber(expression) ? nextSiblings[expression] :
      Selector.findElement(nextSiblings,  expression,  index);
  }, 

  select: function() {
    var args = $A(arguments),  element = $(args.shift());
    return Selector.findChildElements(element,  args);
  }, 

  adjacent: function() {
    var args = $A(arguments),  element = $(args.shift());
    return Selector.findChildElements(element.parentNode,  args).without(element);
  }, 

  identify: function(element) {
    element = $(element);
    var id = element.readAttribute('id'),  self = arguments.callee;
    if (id) return id;
    do { id = 'anonymous_element_' + self.counter++ } while ($(id));
    element.writeAttribute('id',  id);
    return id;
  }, 

  readAttribute: function(element,  name) {
    element = $(element);
    if (Prototype.Browser.IE) {
      var t = Element._attributeTranslations.read;
      if (t.values[name]) return t.values[name](element,  name);
      if (t.names[name]) name = t.names[name];
      if (name.include(':')) {
        return (!element.attributes || !element.attributes[name]) ? null :
         element.attributes[name].value;
      }
    }
    return element.getAttribute(name);
  }, 

  writeAttribute: function(element,  name,  value) {
    element = $(element);
    var attributes = { },  t = Element._attributeTranslations.write;

    if (typeof name == 'object') attributes = name;
    else attributes[name] = Object.isUndefined(value) ? true : value;

    for (var attr in attributes) {
      name = t.names[attr] || attr;
      value = attributes[attr];
      if (t.values[attr]) name = t.values[attr](element,  value);
      if (value === false || value === null)
        element.removeAttribute(name);
      else if (value === true)
        element.setAttribute(name,  name);
      else element.setAttribute(name,  value);
    }
    return element;
  }, 

  getHeight: function(element) {
    return $(element).getDimensions().height;
  }, 

  getWidth: function(element) {
    return $(element).getDimensions().width;
  }, 

  classNames: function(element) {
    return new Element.ClassNames(element);
  }, 

  hasClassName: function(element,  className) {
    if (!(element = $(element))) return;
    var elementClassName = element.className;
    return (elementClassName.length > 0 && (elementClassName == className ||
      new RegExp("(^|\\s)" + className + "(\\s|$)").test(elementClassName)));
  }, 

  addClassName: function(element,  className) {
    if (!(element = $(element))) return;
    if (!element.hasClassName(className))
      element.className += (element.className ? ' ' : '') + className;
    return element;
  }, 

  removeClassName: function(element,  className) {
    if (!(element = $(element))) return;
    element.className = element.className.replace(
      new RegExp("(^|\\s+)" + className + "(\\s+|$)"),  ' ').strip();
    return element;
  }, 

  toggleClassName: function(element,  className) {
    if (!(element = $(element))) return;
    return element[element.hasClassName(className) ?
      'removeClassName' : 'addClassName'](className);
  }, 

  // removes whitespace-only text node children
  cleanWhitespace: function(element) {
    element = $(element);
    var node = element.firstChild;
    while (node) {
      var nextNode = node.nextSibling;
      if (node.nodeType == 3 && !/\S/.test(node.nodeValue))
        element.removeChild(node);
      node = nextNode;
    }
    return element;
  }, 

  empty: function(element) {
    return $(element).innerHTML.blank();
  }, 

  descendantOf: function(element,  ancestor) {
    element = $(element),  ancestor = $(ancestor);
    var originalAncestor = ancestor;

    if (element.compareDocumentPosition)
      return (element.compareDocumentPosition(ancestor) & 8) === 8;

    if (element.sourceIndex && !Prototype.Browser.Opera) {
      var e = element.sourceIndex,  a = ancestor.sourceIndex, 
       nextAncestor = ancestor.nextSibling;
      if (!nextAncestor) {
        do { ancestor = ancestor.parentNode; }
        while (!(nextAncestor = ancestor.nextSibling) && ancestor.parentNode);
      }
      if (nextAncestor && nextAncestor.sourceIndex)
       return (e > a && e < nextAncestor.sourceIndex);
    }

    while (element = element.parentNode)
      if (element == originalAncestor) return true;
    return false;
  }, 

  scrollTo: function(element) {
    element = $(element);
    var pos = element.cumulativeOffset();
    window.scrollTo(pos[0],  pos[1]);
    return element;
  }, 

  getStyle: function(element,  style) {
    element = $(element);
    style = style == 'float' ? 'cssFloat' : style.camelize();
    var value = element.style[style];
    if (!value) {
      var css = document.defaultView.getComputedStyle(element,  null);
      value = css ? css[style] : null;
    }
    if (style == 'opacity') return value ? parseFloat(value) : 1.0;
    return value == 'auto' ? null : value;
  }, 

  getOpacity: function(element) {
    return $(element).getStyle('opacity');
  }, 

  setStyle: function(element,  styles) {
    element = $(element);
    var elementStyle = element.style,  match;
    if (Object.isString(styles)) {
      element.style.cssText += ';' + styles;
      return styles.include('opacity') ?
        element.setOpacity(styles.match(/opacity:\s*(\d?\.?\d*)/)[1]) : element;
    }
    for (var property in styles)
      if (property == 'opacity') element.setOpacity(styles[property]);
      else
        elementStyle[(property == 'float' || property == 'cssFloat') ?
          (Object.isUndefined(elementStyle.styleFloat) ? 'cssFloat' : 'styleFloat') :
            property] = styles[property];

    return element;
  }, 

  setOpacity: function(element,  value) {
    element = $(element);
    element.style.opacity = (value == 1 || value === '') ? '' :
      (value < 0.00001) ? 0 : value;
    return element;
  }, 

  getDimensions: function(element) {
    element = $(element);
    var display = $(element).getStyle('display');
    if (display != 'none' && display != null) // Safari bug
      return {width: element.offsetWidth,  height: element.offsetHeight};

    // All *Width and *Height properties give 0 on elements with display none, 
    // so enable the element temporarily
    var els = element.style;
    var originalVisibility = els.visibility;
    var originalPosition = els.position;
    var originalDisplay = els.display;
    els.visibility = 'hidden';
    els.position = 'absolute';
    els.display = 'block';
    var originalWidth = element.clientWidth;
    var originalHeight = element.clientHeight;
    els.display = originalDisplay;
    els.position = originalPosition;
    els.visibility = originalVisibility;
    return {width: originalWidth,  height: originalHeight};
  }, 

  makePositioned: function(element) {
    element = $(element);
    var pos = Element.getStyle(element,  'position');
    if (pos == 'static' || !pos) {
      element._madePositioned = true;
      element.style.position = 'relative';
      // Opera returns the offset relative to the positioning context,  when an
      // element is position relative but top and left have not been defined
      if (window.opera) {
        element.style.top = 0;
        element.style.left = 0;
      }
    }
    return element;
  }, 

  undoPositioned: function(element) {
    element = $(element);
    if (element._madePositioned) {
      element._madePositioned = undefined;
      element.style.position =
        element.style.top =
        element.style.left =
        element.style.bottom =
        element.style.right = '';
    }
    return element;
  }, 

  makeClipping: function(element) {
    element = $(element);
    if (element._overflow) return element;
    element._overflow = Element.getStyle(element,  'overflow') || 'auto';
    if (element._overflow !== 'hidden')
      element.style.overflow = 'hidden';
    return element;
  }, 

  undoClipping: function(element) {
    element = $(element);
    if (!element._overflow) return element;
    element.style.overflow = element._overflow == 'auto' ? '' : element._overflow;
    element._overflow = null;
    return element;
  }, 

  cumulativeOffset: function(element) {
    var valueT = 0,  valueL = 0;
    do {
      valueT += element.offsetTop  || 0;
      valueL += element.offsetLeft || 0;
      element = element.offsetParent;
    } while (element);
    return Element._returnOffset(valueL,  valueT);
  }, 

  positionedOffset: function(element) {
    var valueT = 0,  valueL = 0;
    do {
      valueT += element.offsetTop  || 0;
      valueL += element.offsetLeft || 0;
      element = element.offsetParent;
      if (element) {
        if (element.tagName == 'BODY') break;
        var p = Element.getStyle(element,  'position');
        if (p !== 'static') break;
      }
    } while (element);
    return Element._returnOffset(valueL,  valueT);
  }, 

  absolutize: function(element) {
    element = $(element);
    if (element.getStyle('position') == 'absolute') return;
    // Position.prepare(); // To be done manually by Scripty when it needs it.

    var offsets = element.positionedOffset();
    var top     = offsets[1];
    var left    = offsets[0];
    var width   = element.clientWidth;
    var height  = element.clientHeight;

    element._originalLeft   = left - parseFloat(element.style.left  || 0);
    element._originalTop    = top  - parseFloat(element.style.top || 0);
    element._originalWidth  = element.style.width;
    element._originalHeight = element.style.height;

    element.style.position = 'absolute';
    element.style.top    = top + 'px';
    element.style.left   = left + 'px';
    element.style.width  = width + 'px';
    element.style.height = height + 'px';
    return element;
  }, 

  relativize: function(element) {
    element = $(element);
    if (element.getStyle('position') == 'relative') return;
    // Position.prepare(); // To be done manually by Scripty when it needs it.

    element.style.position = 'relative';
    var top  = parseFloat(element.style.top  || 0) - (element._originalTop || 0);
    var left = parseFloat(element.style.left || 0) - (element._originalLeft || 0);

    element.style.top    = top + 'px';
    element.style.left   = left + 'px';
    element.style.height = element._originalHeight;
    element.style.width  = element._originalWidth;
    return element;
  }, 

  cumulativeScrollOffset: function(element) {
    var valueT = 0,  valueL = 0;
    do {
      valueT += element.scrollTop  || 0;
      valueL += element.scrollLeft || 0;
      element = element.parentNode;
    } while (element);
    return Element._returnOffset(valueL,  valueT);
  }, 

  getOffsetParent: function(element) {
    if (element.offsetParent) return $(element.offsetParent);
    if (element == document.body) return $(element);

    while ((element = element.parentNode) && element != document.body)
      if (Element.getStyle(element,  'position') != 'static')
        return $(element);

    return $(document.body);
  }, 

  viewportOffset: function(forElement) {
    var valueT = 0,  valueL = 0;

    var element = forElement;
    do {
      valueT += element.offsetTop  || 0;
      valueL += element.offsetLeft || 0;

      // Safari fix
      if (element.offsetParent == document.body &&
        Element.getStyle(element,  'position') == 'absolute') break;

    } while (element = element.offsetParent);

    element = forElement;
    do {
      if (!Prototype.Browser.Opera || element.tagName == 'BODY') {
        valueT -= element.scrollTop  || 0;
        valueL -= element.scrollLeft || 0;
      }
    } while (element = element.parentNode);

    return Element._returnOffset(valueL,  valueT);
  }, 

  clonePosition: function(element,  source) {
    var options = Object.extend({
      setLeft:    true, 
      setTop:     true, 
      setWidth:   true, 
      setHeight:  true, 
      offsetTop:  0, 
      offsetLeft: 0
    },  arguments[2] || { });

    // find page position of source
    source = $(source);
    var p = source.viewportOffset();

    // find coordinate system to use
    element = $(element);
    var delta = [0,  0];
    var parent = null;
    // delta [0, 0] will do fine with position: fixed elements, 
    // position:absolute needs offsetParent deltas
    if (Element.getStyle(element,  'position') == 'absolute') {
      parent = element.getOffsetParent();
      delta = parent.viewportOffset();
    }

    // correct by body offsets (fixes Safari)
    if (parent == document.body) {
      delta[0] -= document.body.offsetLeft;
      delta[1] -= document.body.offsetTop;
    }

    // set position
    if (options.setLeft)   element.style.left  = (p[0] - delta[0] + options.offsetLeft) + 'px';
    if (options.setTop)    element.style.top   = (p[1] - delta[1] + options.offsetTop) + 'px';
    if (options.setWidth)  element.style.width = source.offsetWidth + 'px';
    if (options.setHeight) element.style.height = source.offsetHeight + 'px';
    return element;
  }
};

Element.Methods.identify.counter = 1;

Object.extend(Element.Methods,  {
  getElementsBySelector: Element.Methods.select, 
  childElements: Element.Methods.immediateDescendants
});

Element._attributeTranslations = {
  write: {
    names: {
      className: 'class', 
      htmlFor:   'for'
    }, 
    values: { }
  }
};

if (Prototype.Browser.Opera) {
  Element.Methods.getStyle = Element.Methods.getStyle.wrap(
    function(proceed,  element,  style) {
      switch (style) {
        case 'left': case 'top': case 'right': case 'bottom':
          if (proceed(element,  'position') === 'static') return null;
        case 'height': case 'width':
          // returns '0px' for hidden elements; we want it to return null
          if (!Element.visible(element)) return null;

          // returns the border-box dimensions rather than the content-box
          // dimensions,  so we subtract padding and borders from the value
          var dim = parseInt(proceed(element,  style),  10);

          if (dim !== element['offset' + style.capitalize()])
            return dim + 'px';

          var properties;
          if (style === 'height') {
            properties = ['border-top-width',  'padding-top', 
             'padding-bottom',  'border-bottom-width'];
          }
          else {
            properties = ['border-left-width',  'padding-left', 
             'padding-right',  'border-right-width'];
          }
          return properties.inject(dim,  function(memo,  property) {
            var val = proceed(element,  property);
            return val === null ? memo : memo - parseInt(val,  10);
          }) + 'px';
        default: return proceed(element,  style);
      }
    }
  );

  Element.Methods.readAttribute = Element.Methods.readAttribute.wrap(
    function(proceed,  element,  attribute) {
      if (attribute === 'title') return element.title;
      return proceed(element,  attribute);
    }
  );
}

else if (Prototype.Browser.IE) {
  // IE doesn't report offsets correctly for static elements,  so we change them
  // to "relative" to get the values,  then change them back.
  Element.Methods.getOffsetParent = Element.Methods.getOffsetParent.wrap(
    function(proceed,  element) {
      element = $(element);
      var position = element.getStyle('position');
      if (position !== 'static') return proceed(element);
      element.setStyle({ position: 'relative' });
      var value = proceed(element);
      element.setStyle({ position: position });
      return value;
    }
  );

  $w('positionedOffset viewportOffset').each(function(method) {
    Element.Methods[method] = Element.Methods[method].wrap(
      function(proceed,  element) {
        element = $(element);
        var position = element.getStyle('position');
        if (position !== 'static') return proceed(element);
        // Trigger hasLayout on the offset parent so that IE6 reports
        // accurate offsetTop and offsetLeft values for position: fixed.
        var offsetParent = element.getOffsetParent();
        if (offsetParent && offsetParent.getStyle('position') === 'fixed')
          offsetParent.setStyle({ zoom: 1 });
        element.setStyle({ position: 'relative' });
        var value = proceed(element);
        element.setStyle({ position: position });
        return value;
      }
    );
  });

  Element.Methods.getStyle = function(element,  style) {
    element = $(element);
    style = (style == 'float' || style == 'cssFloat') ? 'styleFloat' : style.camelize();
    var value = element.style[style];
    if (!value && element.currentStyle) value = element.currentStyle[style];

    if (style == 'opacity') {
      if (value = (element.getStyle('filter') || '').match(/alpha\(opacity=(.*)\)/))
        if (value[1]) return parseFloat(value[1]) / 100;
      return 1.0;
    }

    if (value == 'auto') {
      if ((style == 'width' || style == 'height') && (element.getStyle('display') != 'none'))
        return element['offset' + style.capitalize()] + 'px';
      return null;
    }
    return value;
  };

  Element.Methods.setOpacity = function(element,  value) {
    function stripAlpha(filter){
      return filter.replace(/alpha\([^\)]*\)/gi, '');
    }
    element = $(element);
    var currentStyle = element.currentStyle;
    if ((currentStyle && !currentStyle.hasLayout) ||
      (!currentStyle && element.style.zoom == 'normal'))
        element.style.zoom = 1;

    var filter = element.getStyle('filter'),  style = element.style;
    if (value == 1 || value === '') {
      (filter = stripAlpha(filter)) ?
        style.filter = filter : style.removeAttribute('filter');
      return element;
    } else if (value < 0.00001) value = 0;
    style.filter = stripAlpha(filter) +
      'alpha(opacity=' + (value * 100) + ')';
    return element;
  };

  Element._attributeTranslations = {
    read: {
      names: {
        'class': 'className', 
        'for':   'htmlFor'
      }, 
      values: {
        _getAttr: function(element,  attribute) {
          return element.getAttribute(attribute,  2);
        }, 
        _getAttrNode: function(element,  attribute) {
          var node = element.getAttributeNode(attribute);
          return node ? node.value : "";
        }, 
        _getEv: function(element,  attribute) {
          attribute = element.getAttribute(attribute);
          return attribute ? attribute.toString().slice(23,  -2) : null;
        }, 
        _flag: function(element,  attribute) {
          return $(element).hasAttribute(attribute) ? attribute : null;
        }, 
        style: function(element) {
          return element.style.cssText.toLowerCase();
        }, 
        title: function(element) {
          return element.title;
        }
      }
    }
  };

  Element._attributeTranslations.write = {
    names: Object.extend({
      cellpadding: 'cellPadding', 
      cellspacing: 'cellSpacing'
    },  Element._attributeTranslations.read.names), 
    values: {
      checked: function(element,  value) {
        element.checked = !!value;
      }, 

      style: function(element,  value) {
        element.style.cssText = value ? value : '';
      }
    }
  };

  Element._attributeTranslations.has = {};

  $w('colSpan rowSpan vAlign dateTime accessKey tabIndex ' +
      'encType maxLength readOnly longDesc').each(function(attr) {
    Element._attributeTranslations.write.names[attr.toLowerCase()] = attr;
    Element._attributeTranslations.has[attr.toLowerCase()] = attr;
  });

  (function(v) {
    Object.extend(v,  {
      href:        v._getAttr, 
      src:         v._getAttr, 
      type:        v._getAttr, 
      action:      v._getAttrNode, 
      disabled:    v._flag, 
      checked:     v._flag, 
      readonly:    v._flag, 
      multiple:    v._flag, 
      onload:      v._getEv, 
      onunload:    v._getEv, 
      onclick:     v._getEv, 
      ondblclick:  v._getEv, 
      onmousedown: v._getEv, 
      onmouseup:   v._getEv, 
      onmouseover: v._getEv, 
      onmousemove: v._getEv, 
      onmouseout:  v._getEv, 
      onfocus:     v._getEv, 
      onblur:      v._getEv, 
      onkeypress:  v._getEv, 
      onkeydown:   v._getEv, 
      onkeyup:     v._getEv, 
      onsubmit:    v._getEv, 
      onreset:     v._getEv, 
      onselect:    v._getEv, 
      onchange:    v._getEv
    });
  })(Element._attributeTranslations.read.values);
}

else if (Prototype.Browser.Gecko && /rv:1\.8\.0/.test(navigator.userAgent)) {
  Element.Methods.setOpacity = function(element,  value) {
    element = $(element);
    element.style.opacity = (value == 1) ? 0.999999 :
      (value === '') ? '' : (value < 0.00001) ? 0 : value;
    return element;
  };
}

else if (Prototype.Browser.WebKit) {
  Element.Methods.setOpacity = function(element,  value) {
    element = $(element);
    element.style.opacity = (value == 1 || value === '') ? '' :
      (value < 0.00001) ? 0 : value;

    if (value == 1)
      if(element.tagName == 'IMG' && element.width) {
        element.width++; element.width--;
      } else try {
        var n = document.createTextNode(' ');
        element.appendChild(n);
        element.removeChild(n);
      } catch (e) { }

    return element;
  };

  // Safari returns margins on body which is incorrect if the child is absolutely
  // positioned.  For performance reasons,  redefine Element#cumulativeOffset for
  // KHTML/WebKit only.
  Element.Methods.cumulativeOffset = function(element) {
    var valueT = 0,  valueL = 0;
    do {
      valueT += element.offsetTop  || 0;
      valueL += element.offsetLeft || 0;
      if (element.offsetParent == document.body)
        if (Element.getStyle(element,  'position') == 'absolute') break;

      element = element.offsetParent;
    } while (element);

    return Element._returnOffset(valueL,  valueT);
  };
}

if (Prototype.Browser.IE || Prototype.Browser.Opera) {
  // IE and Opera are missing .innerHTML support for TABLE-related and SELECT elements
  Element.Methods.update = function(element,  content) {
    element = $(element);

    if (content && content.toElement) content = content.toElement();
    if (Object.isElement(content)) return element.update().insert(content);

    content = Object.toHTML(content);
    var tagName = element.tagName.toUpperCase();

    if (tagName in Element._insertionTranslations.tags) {
      $A(element.childNodes).each(function(node) { element.removeChild(node) });
      Element._getContentFromAnonymousElement(tagName,  content.stripScripts())
        .each(function(node) { element.appendChild(node) });
    }
    else element.innerHTML = content.stripScripts();

    content.evalScripts.bind(content).defer();
    return element;
  };
}

if ('outerHTML' in document.createElement('div')) {
  Element.Methods.replace = function(element,  content) {
    element = $(element);

    if (content && content.toElement) content = content.toElement();
    if (Object.isElement(content)) {
      element.parentNode.replaceChild(content,  element);
      return element;
    }

    content = Object.toHTML(content);
    var parent = element.parentNode,  tagName = parent.tagName.toUpperCase();

    if (Element._insertionTranslations.tags[tagName]) {
      var nextSibling = element.next();
      var fragments = Element._getContentFromAnonymousElement(tagName,  content.stripScripts());
      parent.removeChild(element);
      if (nextSibling)
        fragments.each(function(node) { parent.insertBefore(node,  nextSibling) });
      else
        fragments.each(function(node) { parent.appendChild(node) });
    }
    else element.outerHTML = content.stripScripts();

    content.evalScripts.bind(content).defer();
    return element;
  };
}

Element._returnOffset = function(l,  t) {
  var result = [l,  t];
  result.left = l;
  result.top = t;
  return result;
};

Element._getContentFromAnonymousElement = function(tagName,  html) {
  var div = new Element('div'),  t = Element._insertionTranslations.tags[tagName];
  if (t) {
    div.innerHTML = t[0] + html + t[1];
    t[2].times(function() { div = div.firstChild });
  } else div.innerHTML = html;
  return $A(div.childNodes);
};

Element._insertionTranslations = {
  before: function(element,  node) {
    element.parentNode.insertBefore(node,  element);
  }, 
  top: function(element,  node) {
    element.insertBefore(node,  element.firstChild);
  }, 
  bottom: function(element,  node) {
    element.appendChild(node);
  }, 
  after: function(element,  node) {
    element.parentNode.insertBefore(node,  element.nextSibling);
  }, 
  tags: {
    TABLE:  ['<table>',                 '</table>',                    1], 
    TBODY:  ['<table><tbody>',          '</tbody></table>',            2], 
    TR:     ['<table><tbody><tr>',      '</tr></tbody></table>',       3], 
    TD:     ['<table><tbody><tr><td>',  '</td></tr></tbody></table>',  4], 
    SELECT: ['<select>',                '</select>',                   1]
  }
};

(function() {
  Object.extend(this.tags,  {
    THEAD: this.tags.TBODY, 
    TFOOT: this.tags.TBODY, 
    TH:    this.tags.TD
  });
}).call(Element._insertionTranslations);

Element.Methods.Simulated = {
  hasAttribute: function(element,  attribute) {
    attribute = Element._attributeTranslations.has[attribute] || attribute;
    var node = $(element).getAttributeNode(attribute);
    return node && node.specified;
  }
};

Element.Methods.ByTag = { };

Object.extend(Element,  Element.Methods);

if (!Prototype.BrowserFeatures.ElementExtensions &&
    document.createElement('div').__proto__) {
  window.HTMLElement = { };
  window.HTMLElement.prototype = document.createElement('div').__proto__;
  Prototype.BrowserFeatures.ElementExtensions = true;
}

Element.extend = (function() {
  if (Prototype.BrowserFeatures.SpecificElementExtensions)
    return Prototype.K;

  var Methods = { },  ByTag = Element.Methods.ByTag;

  var extend = Object.extend(function(element) {
    if (!element || element._extendedByPrototype ||
        element.nodeType != 1 || element == window) return element;

    var methods = Object.clone(Methods), 
      tagName = element.tagName,  property,  value;

    // extend methods for specific tags
    if (ByTag[tagName]) Object.extend(methods,  ByTag[tagName]);

    for (property in methods) {
      value = methods[property];
      if (Object.isFunction(value) && !(property in element))
        element[property] = value.methodize();
    }

    element._extendedByPrototype = Prototype.emptyFunction;
    return element;

  },  {
    refresh: function() {
      // extend methods for all tags (Safari doesn't need this)
      if (!Prototype.BrowserFeatures.ElementExtensions) {
        Object.extend(Methods,  Element.Methods);
        Object.extend(Methods,  Element.Methods.Simulated);
      }
    }
  });

  extend.refresh();
  return extend;
})();

Element.hasAttribute = function(element,  attribute) {
  if (element.hasAttribute) return element.hasAttribute(attribute);
  return Element.Methods.Simulated.hasAttribute(element,  attribute);
};

Element.addMethods = function(methods) {
  var F = Prototype.BrowserFeatures,  T = Element.Methods.ByTag;

  if (!methods) {
    Object.extend(Form,  Form.Methods);
    Object.extend(Form.Element,  Form.Element.Methods);
    Object.extend(Element.Methods.ByTag,  {
      "FORM":     Object.clone(Form.Methods), 
      "INPUT":    Object.clone(Form.Element.Methods), 
      "SELECT":   Object.clone(Form.Element.Methods), 
      "TEXTAREA": Object.clone(Form.Element.Methods)
    });
  }

  if (arguments.length == 2) {
    var tagName = methods;
    methods = arguments[1];
  }

  if (!tagName) Object.extend(Element.Methods,  methods || { });
  else {
    if (Object.isArray(tagName)) tagName.each(extend);
    else extend(tagName);
  }

  function extend(tagName) {
    tagName = tagName.toUpperCase();
    if (!Element.Methods.ByTag[tagName])
      Element.Methods.ByTag[tagName] = { };
    Object.extend(Element.Methods.ByTag[tagName],  methods);
  }

  function copy(methods,  destination,  onlyIfAbsent) {
    onlyIfAbsent = onlyIfAbsent || false;
    for (var property in methods) {
      var value = methods[property];
      if (!Object.isFunction(value)) continue;
      if (!onlyIfAbsent || !(property in destination))
        destination[property] = value.methodize();
    }
  }

  function findDOMClass(tagName) {
    var klass;
    var trans = {
      "OPTGROUP": "OptGroup",  "TEXTAREA": "TextArea",  "P": "Paragraph", 
      "FIELDSET": "FieldSet",  "UL": "UList",  "OL": "OList",  "DL": "DList", 
      "DIR": "Directory",  "H1": "Heading",  "H2": "Heading",  "H3": "Heading", 
      "H4": "Heading",  "H5": "Heading",  "H6": "Heading",  "Q": "Quote", 
      "INS": "Mod",  "DEL": "Mod",  "A": "Anchor",  "IMG": "Image",  "CAPTION":
      "TableCaption",  "COL": "TableCol",  "COLGROUP": "TableCol",  "THEAD":
      "TableSection",  "TFOOT": "TableSection",  "TBODY": "TableSection",  "TR":
      "TableRow",  "TH": "TableCell",  "TD": "TableCell",  "FRAMESET":
      "FrameSet",  "IFRAME": "IFrame"
    };
    if (trans[tagName]) klass = 'HTML' + trans[tagName] + 'Element';
    if (window[klass]) return window[klass];
    klass = 'HTML' + tagName + 'Element';
    if (window[klass]) return window[klass];
    klass = 'HTML' + tagName.capitalize() + 'Element';
    if (window[klass]) return window[klass];

    window[klass] = { };
    window[klass].prototype = document.createElement(tagName).__proto__;
    return window[klass];
  }

  if (F.ElementExtensions) {
    copy(Element.Methods,  HTMLElement.prototype);
    copy(Element.Methods.Simulated,  HTMLElement.prototype,  true);
  }

  if (F.SpecificElementExtensions) {
    for (var tag in Element.Methods.ByTag) {
      var klass = findDOMClass(tag);
      if (Object.isUndefined(klass)) continue;
      copy(T[tag],  klass.prototype);
    }
  }

  Object.extend(Element,  Element.Methods);
  delete Element.ByTag;

  if (Element.extend.refresh) Element.extend.refresh();
  Element.cache = { };
};

document.viewport = {
  getDimensions: function() {
    var dimensions = { };
    var B = Prototype.Browser;
    $w('width height').each(function(d) {
      var D = d.capitalize();
      dimensions[d] = (B.WebKit && !document.evaluate) ? self['inner' + D] :
        (B.Opera) ? document.body['client' + D] : document.documentElement['client' + D];
    });
    return dimensions;
  }, 

  getWidth: function() {
    return this.getDimensions().width;
  }, 

  getHeight: function() {
    return this.getDimensions().height;
  }, 

  getScrollOffsets: function() {
    return Element._returnOffset(
      window.pageXOffset || document.documentElement.scrollLeft || document.body.scrollLeft, 
      window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop);
  }
};
/* Portions of the Selector class are derived from Jack Slocum’s DomQuery, 
 * part of YUI-Ext version 0.40,  distributed under the terms of an MIT-style
 * license.  Please see http://www.yui-ext.com/ for more information. */

var Selector = Class.create({
  initialize: function(expression) {
    this.expression = expression.strip();
    this.compileMatcher();
  }, 

  shouldUseXPath: function() {
    if (!Prototype.BrowserFeatures.XPath) return false;

    var e = this.expression;

    // Safari 3 chokes on :*-of-type and :empty
    if (Prototype.Browser.WebKit &&
     (e.include("-of-type") || e.include(":empty")))
      return false;

    // XPath can't do namespaced attributes,  nor can it read
    // the "checked" property from DOM nodes
    if ((/(\[[\w-]*?:|:checked)/).test(this.expression))
      return false;

    return true;
  }, 

  compileMatcher: function() {
    if (this.shouldUseXPath())
      return this.compileXPathMatcher();

    var e = this.expression,  ps = Selector.patterns,  h = Selector.handlers, 
        c = Selector.criteria,  le,  p,  m;

    if (Selector._cache[e]) {
      this.matcher = Selector._cache[e];
      return;
    }

    this.matcher = ["this.matcher = function(root) {", 
                    "var r = root,  h = Selector.handlers,  c = false,  n;"];

    while (e && le != e && (/\S/).test(e)) {
      le = e;
      for (var i in ps) {
        p = ps[i];
        if (m = e.match(p)) {
          this.matcher.push(Object.isFunction(c[i]) ? c[i](m) :
    	      new Template(c[i]).evaluate(m));
          e = e.replace(m[0],  '');
          break;
        }
      }
    }

    this.matcher.push("return h.unique(n);\n}");
    eval(this.matcher.join('\n'));
    Selector._cache[this.expression] = this.matcher;
  }, 

  compileXPathMatcher: function() {
    var e = this.expression,  ps = Selector.patterns, 
        x = Selector.xpath,  le,  m;

    if (Selector._cache[e]) {
      this.xpath = Selector._cache[e]; return;
    }

    this.matcher = ['.//*'];
    while (e && le != e && (/\S/).test(e)) {
      le = e;
      for (var i in ps) {
        if (m = e.match(ps[i])) {
          this.matcher.push(Object.isFunction(x[i]) ? x[i](m) :
            new Template(x[i]).evaluate(m));
          e = e.replace(m[0],  '');
          break;
        }
      }
    }

    this.xpath = this.matcher.join('');
    Selector._cache[this.expression] = this.xpath;
  }, 

  findElements: function(root) {
    root = root || document;
    if (this.xpath) return document._getElementsByXPath(this.xpath,  root);
    return this.matcher(root);
  }, 

  match: function(element) {
    this.tokens = [];

    var e = this.expression,  ps = Selector.patterns,  as = Selector.assertions;
    var le,  p,  m;

    while (e && le !== e && (/\S/).test(e)) {
      le = e;
      for (var i in ps) {
        p = ps[i];
        if (m = e.match(p)) {
          // use the Selector.assertions methods unless the selector
          // is too complex.
          if (as[i]) {
            this.tokens.push([i,  Object.clone(m)]);
            e = e.replace(m[0],  '');
          } else {
            // reluctantly do a document-wide search
            // and look for a match in the array
            return this.findElements(document).include(element);
          }
        }
      }
    }

    var match = true,  name,  matches;
    for (var i = 0,  token; token = this.tokens[i]; i++) {
      name = token[0],  matches = token[1];
      if (!Selector.assertions[name](element,  matches)) {
        match = false; break;
      }
    }

    return match;
  }, 

  toString: function() {
    return this.expression;
  }, 

  inspect: function() {
    return "#<Selector:" + this.expression.inspect() + ">";
  }
});

Object.extend(Selector,  {
  _cache: { }, 

  xpath: {
    descendant:   "//*", 
    child:        "/*", 
    adjacent:     "/following-sibling::*[1]", 
    laterSibling: '/following-sibling::*', 
    tagName:      function(m) {
      if (m[1] == '*') return '';
      return "[local-name()='" + m[1].toLowerCase() +
             "' or local-name()='" + m[1].toUpperCase() + "']";
    }, 
    className:    "[contains(concat(' ',  @class,  ' '),  ' #{1} ')]", 
    id:           "[@id='#{1}']", 
    attrPresence: function(m) {
      m[1] = m[1].toLowerCase();
      return new Template("[@#{1}]").evaluate(m);
    }, 
    attr: function(m) {
      m[1] = m[1].toLowerCase();
      m[3] = m[5] || m[6];
      return new Template(Selector.xpath.operators[m[2]]).evaluate(m);
    }, 
    pseudo: function(m) {
      var h = Selector.xpath.pseudos[m[1]];
      if (!h) return '';
      if (Object.isFunction(h)) return h(m);
      return new Template(Selector.xpath.pseudos[m[1]]).evaluate(m);
    }, 
    operators: {
      '=':  "[@#{1}='#{3}']", 
      '!=': "[@#{1}!='#{3}']", 
      '^=': "[starts-with(@#{1},  '#{3}')]", 
      '$=': "[substring(@#{1},  (string-length(@#{1}) - string-length('#{3}') + 1))='#{3}']", 
      '*=': "[contains(@#{1},  '#{3}')]", 
      '~=': "[contains(concat(' ',  @#{1},  ' '),  ' #{3} ')]", 
      '|=': "[contains(concat('-',  @#{1},  '-'),  '-#{3}-')]"
    }, 
    pseudos: {
      'first-child': '[not(preceding-sibling::*)]', 
      'last-child':  '[not(following-sibling::*)]', 
      'only-child':  '[not(preceding-sibling::* or following-sibling::*)]', 
      'empty':       "[count(*) = 0 and (count(text()) = 0 or translate(text(),  ' \t\r\n',  '') = '')]", 
      'checked':     "[@checked]", 
      'disabled':    "[@disabled]", 
      'enabled':     "[not(@disabled)]", 
      'not': function(m) {
        var e = m[6],  p = Selector.patterns, 
            x = Selector.xpath,  le,  v;

        var exclusion = [];
        while (e && le != e && (/\S/).test(e)) {
          le = e;
          for (var i in p) {
            if (m = e.match(p[i])) {
              v = Object.isFunction(x[i]) ? x[i](m) : new Template(x[i]).evaluate(m);
              exclusion.push("(" + v.substring(1,  v.length - 1) + ")");
              e = e.replace(m[0],  '');
              break;
            }
          }
        }
        return "[not(" + exclusion.join(" and ") + ")]";
      }, 
      'nth-child':      function(m) {
        return Selector.xpath.pseudos.nth("(count(./preceding-sibling::*) + 1) ",  m);
      }, 
      'nth-last-child': function(m) {
        return Selector.xpath.pseudos.nth("(count(./following-sibling::*) + 1) ",  m);
      }, 
      'nth-of-type':    function(m) {
        return Selector.xpath.pseudos.nth("position() ",  m);
      }, 
      'nth-last-of-type': function(m) {
        return Selector.xpath.pseudos.nth("(last() + 1 - position()) ",  m);
      }, 
      'first-of-type':  function(m) {
        m[6] = "1"; return Selector.xpath.pseudos['nth-of-type'](m);
      }, 
      'last-of-type':   function(m) {
        m[6] = "1"; return Selector.xpath.pseudos['nth-last-of-type'](m);
      }, 
      'only-of-type':   function(m) {
        var p = Selector.xpath.pseudos; return p['first-of-type'](m) + p['last-of-type'](m);
      }, 
      nth: function(fragment,  m) {
        var mm,  formula = m[6],  predicate;
        if (formula == 'even') formula = '2n+0';
        if (formula == 'odd')  formula = '2n+1';
        if (mm = formula.match(/^(\d+)$/)) // digit only
          return '[' + fragment + "= " + mm[1] + ']';
        if (mm = formula.match(/^(-?\d*)?n(([+-])(\d+))?/)) { // an+b
          if (mm[1] == "-") mm[1] = -1;
          var a = mm[1] ? Number(mm[1]) : 1;
          var b = mm[2] ? Number(mm[2]) : 0;
          predicate = "[((#{fragment} - #{b}) mod #{a} = 0) and " +
          "((#{fragment} - #{b}) div #{a} >= 0)]";
          return new Template(predicate).evaluate({
            fragment: fragment,  a: a,  b: b });
        }
      }
    }
  }, 

  criteria: {
    tagName:      'n = h.tagName(n,  r,  "#{1}",  c);      c = false;', 
    className:    'n = h.className(n,  r,  "#{1}",  c);    c = false;', 
    id:           'n = h.id(n,  r,  "#{1}",  c);           c = false;', 
    attrPresence: 'n = h.attrPresence(n,  r,  "#{1}",  c); c = false;', 
    attr: function(m) {
      m[3] = (m[5] || m[6]);
      return new Template('n = h.attr(n,  r,  "#{1}",  "#{3}",  "#{2}",  c); c = false;').evaluate(m);
    }, 
    pseudo: function(m) {
      if (m[6]) m[6] = m[6].replace(/"/g,  '\\"');
      return new Template('n = h.pseudo(n,  "#{1}",  "#{6}",  r,  c); c = false;').evaluate(m);
    }, 
    descendant:   'c = "descendant";', 
    child:        'c = "child";', 
    adjacent:     'c = "adjacent";', 
    laterSibling: 'c = "laterSibling";'
  }, 

  patterns: {
    // combinators must be listed first
    // (and descendant needs to be last combinator)
    laterSibling: /^\s*~\s*/, 
    child:        /^\s*>\s*/, 
    adjacent:     /^\s*\+\s*/, 
    descendant:   /^\s/, 

    // selectors follow
    tagName:      /^\s*(\*|[\w\-]+)(\b|$)?/, 
    id:           /^#([\w\-\*]+)(\b|$)/, 
    className:    /^\.([\w\-\*]+)(\b|$)/, 
    pseudo:
/^:((first|last|nth|nth-last|only)(-child|-of-type)|empty|checked|(en|dis)abled|not)(\((.*?)\))?(\b|$|(?=\s|[:+~>]))/, 
    attrPresence: /^\[([\w]+)\]/, 
    attr:         /\[((?:[\w-]*:)?[\w-]+)\s*(?:([!^$*~|]?=)\s*((['"])([^\4]*?)\4|([^'"][^\]]*?)))?\]/
  }, 

  // for Selector.match and Element#match
  assertions: {
    tagName: function(element,  matches) {
      return matches[1].toUpperCase() == element.tagName.toUpperCase();
    }, 

    className: function(element,  matches) {
      return Element.hasClassName(element,  matches[1]);
    }, 

    id: function(element,  matches) {
      return element.id === matches[1];
    }, 

    attrPresence: function(element,  matches) {
      return Element.hasAttribute(element,  matches[1]);
    }, 

    attr: function(element,  matches) {
      var nodeValue = Element.readAttribute(element,  matches[1]);
      return nodeValue && Selector.operators[matches[2]](nodeValue,  matches[5] || matches[6]);
    }
  }, 

  handlers: {
    // UTILITY FUNCTIONS
    // joins two collections
    concat: function(a,  b) {
      for (var i = 0,  node; node = b[i]; i++)
        a.push(node);
      return a;
    }, 

    // marks an array of nodes for counting
    mark: function(nodes) {
      var _true = Prototype.emptyFunction;
      for (var i = 0,  node; node = nodes[i]; i++)
        node._countedByPrototype = _true;
      return nodes;
    }, 

    unmark: function(nodes) {
      for (var i = 0,  node; node = nodes[i]; i++)
        node._countedByPrototype = undefined;
      return nodes;
    }, 

    // mark each child node with its position (for nth calls)
    // "ofType" flag indicates whether we're indexing for nth-of-type
    // rather than nth-child
    index: function(parentNode,  reverse,  ofType) {
      parentNode._countedByPrototype = Prototype.emptyFunction;
      if (reverse) {
        for (var nodes = parentNode.childNodes,  i = nodes.length - 1,  j = 1; i >= 0; i--) {
          var node = nodes[i];
          if (node.nodeType == 1 && (!ofType || node._countedByPrototype)) node.nodeIndex = j++;
        }
      } else {
        for (var i = 0,  j = 1,  nodes = parentNode.childNodes; node = nodes[i]; i++)
          if (node.nodeType == 1 && (!ofType || node._countedByPrototype)) node.nodeIndex = j++;
      }
    }, 

    // filters out duplicates and extends all nodes
    unique: function(nodes) {
      if (nodes.length == 0) return nodes;
      var results = [],  n;
      for (var i = 0,  l = nodes.length; i < l; i++)
        if (!(n = nodes[i])._countedByPrototype) {
          n._countedByPrototype = Prototype.emptyFunction;
          results.push(Element.extend(n));
        }
      return Selector.handlers.unmark(results);
    }, 

    // COMBINATOR FUNCTIONS
    descendant: function(nodes) {
      var h = Selector.handlers;
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        h.concat(results,  node.getElementsByTagName('*'));
      return results;
    }, 

    child: function(nodes) {
      var h = Selector.handlers;
      for (var i = 0,  results = [],  node; node = nodes[i]; i++) {
        for (var j = 0,  child; child = node.childNodes[j]; j++)
          if (child.nodeType == 1 && child.tagName != '!') results.push(child);
      }
      return results;
    }, 

    adjacent: function(nodes) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++) {
        var next = this.nextElementSibling(node);
        if (next) results.push(next);
      }
      return results;
    }, 

    laterSibling: function(nodes) {
      var h = Selector.handlers;
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        h.concat(results,  Element.nextSiblings(node));
      return results;
    }, 

    nextElementSibling: function(node) {
      while (node = node.nextSibling)
	      if (node.nodeType == 1) return node;
      return null;
    }, 

    previousElementSibling: function(node) {
      while (node = node.previousSibling)
        if (node.nodeType == 1) return node;
      return null;
    }, 

    // TOKEN FUNCTIONS
    tagName: function(nodes,  root,  tagName,  combinator) {
      var uTagName = tagName.toUpperCase();
      var results = [],  h = Selector.handlers;
      if (nodes) {
        if (combinator) {
          // fastlane for ordinary descendant combinators
          if (combinator == "descendant") {
            for (var i = 0,  node; node = nodes[i]; i++)
              h.concat(results,  node.getElementsByTagName(tagName));
            return results;
          } else nodes = this[combinator](nodes);
          if (tagName == "*") return nodes;
        }
        for (var i = 0,  node; node = nodes[i]; i++)
          if (node.tagName.toUpperCase() === uTagName) results.push(node);
        return results;
      } else return root.getElementsByTagName(tagName);
    }, 

    id: function(nodes,  root,  id,  combinator) {
      var targetNode = $(id),  h = Selector.handlers;
      if (!targetNode) return [];
      if (!nodes && root == document) return [targetNode];
      if (nodes) {
        if (combinator) {
          if (combinator == 'child') {
            for (var i = 0,  node; node = nodes[i]; i++)
              if (targetNode.parentNode == node) return [targetNode];
          } else if (combinator == 'descendant') {
            for (var i = 0,  node; node = nodes[i]; i++)
              if (Element.descendantOf(targetNode,  node)) return [targetNode];
          } else if (combinator == 'adjacent') {
            for (var i = 0,  node; node = nodes[i]; i++)
              if (Selector.handlers.previousElementSibling(targetNode) == node)
                return [targetNode];
          } else nodes = h[combinator](nodes);
        }
        for (var i = 0,  node; node = nodes[i]; i++)
          if (node == targetNode) return [targetNode];
        return [];
      }
      return (targetNode && Element.descendantOf(targetNode,  root)) ? [targetNode] : [];
    }, 

    className: function(nodes,  root,  className,  combinator) {
      if (nodes && combinator) nodes = this[combinator](nodes);
      return Selector.handlers.byClassName(nodes,  root,  className);
    }, 

    byClassName: function(nodes,  root,  className) {
      if (!nodes) nodes = Selector.handlers.descendant([root]);
      var needle = ' ' + className + ' ';
      for (var i = 0,  results = [],  node,  nodeClassName; node = nodes[i]; i++) {
        nodeClassName = node.className;
        if (nodeClassName.length == 0) continue;
        if (nodeClassName == className || (' ' + nodeClassName + ' ').include(needle))
          results.push(node);
      }
      return results;
    }, 

    attrPresence: function(nodes,  root,  attr,  combinator) {
      if (!nodes) nodes = root.getElementsByTagName("*");
      if (nodes && combinator) nodes = this[combinator](nodes);
      var results = [];
      for (var i = 0,  node; node = nodes[i]; i++)
        if (Element.hasAttribute(node,  attr)) results.push(node);
      return results;
    }, 

    attr: function(nodes,  root,  attr,  value,  operator,  combinator) {
      if (!nodes) nodes = root.getElementsByTagName("*");
      if (nodes && combinator) nodes = this[combinator](nodes);
      var handler = Selector.operators[operator],  results = [];
      for (var i = 0,  node; node = nodes[i]; i++) {
        var nodeValue = Element.readAttribute(node,  attr);
        if (nodeValue === null) continue;
        if (handler(nodeValue,  value)) results.push(node);
      }
      return results;
    }, 

    pseudo: function(nodes,  name,  value,  root,  combinator) {
      if (nodes && combinator) nodes = this[combinator](nodes);
      if (!nodes) nodes = root.getElementsByTagName("*");
      return Selector.pseudos[name](nodes,  value,  root);
    }
  }, 

  pseudos: {
    'first-child': function(nodes,  value,  root) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++) {
        if (Selector.handlers.previousElementSibling(node)) continue;
          results.push(node);
      }
      return results;
    }, 
    'last-child': function(nodes,  value,  root) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++) {
        if (Selector.handlers.nextElementSibling(node)) continue;
          results.push(node);
      }
      return results;
    }, 
    'only-child': function(nodes,  value,  root) {
      var h = Selector.handlers;
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        if (!h.previousElementSibling(node) && !h.nextElementSibling(node))
          results.push(node);
      return results;
    }, 
    'nth-child':        function(nodes,  formula,  root) {
      return Selector.pseudos.nth(nodes,  formula,  root);
    }, 
    'nth-last-child':   function(nodes,  formula,  root) {
      return Selector.pseudos.nth(nodes,  formula,  root,  true);
    }, 
    'nth-of-type':      function(nodes,  formula,  root) {
      return Selector.pseudos.nth(nodes,  formula,  root,  false,  true);
    }, 
    'nth-last-of-type': function(nodes,  formula,  root) {
      return Selector.pseudos.nth(nodes,  formula,  root,  true,  true);
    }, 
    'first-of-type':    function(nodes,  formula,  root) {
      return Selector.pseudos.nth(nodes,  "1",  root,  false,  true);
    }, 
    'last-of-type':     function(nodes,  formula,  root) {
      return Selector.pseudos.nth(nodes,  "1",  root,  true,  true);
    }, 
    'only-of-type':     function(nodes,  formula,  root) {
      var p = Selector.pseudos;
      return p['last-of-type'](p['first-of-type'](nodes,  formula,  root),  formula,  root);
    }, 

    // handles the an+b logic
    getIndices: function(a,  b,  total) {
      if (a == 0) return b > 0 ? [b] : [];
      return $R(1,  total).inject([],  function(memo,  i) {
        if (0 == (i - b) % a && (i - b) / a >= 0) memo.push(i);
        return memo;
      });
    }, 

    // handles nth(-last)-child,  nth(-last)-of-type,  and (first|last)-of-type
    nth: function(nodes,  formula,  root,  reverse,  ofType) {
      if (nodes.length == 0) return [];
      if (formula == 'even') formula = '2n+0';
      if (formula == 'odd')  formula = '2n+1';
      var h = Selector.handlers,  results = [],  indexed = [],  m;
      h.mark(nodes);
      for (var i = 0,  node; node = nodes[i]; i++) {
        if (!node.parentNode._countedByPrototype) {
          h.index(node.parentNode,  reverse,  ofType);
          indexed.push(node.parentNode);
        }
      }
      if (formula.match(/^\d+$/)) { // just a number
        formula = Number(formula);
        for (var i = 0,  node; node = nodes[i]; i++)
          if (node.nodeIndex == formula) results.push(node);
      } else if (m = formula.match(/^(-?\d*)?n(([+-])(\d+))?/)) { // an+b
        if (m[1] == "-") m[1] = -1;
        var a = m[1] ? Number(m[1]) : 1;
        var b = m[2] ? Number(m[2]) : 0;
        var indices = Selector.pseudos.getIndices(a,  b,  nodes.length);
        for (var i = 0,  node,  l = indices.length; node = nodes[i]; i++) {
          for (var j = 0; j < l; j++)
            if (node.nodeIndex == indices[j]) results.push(node);
        }
      }
      h.unmark(nodes);
      h.unmark(indexed);
      return results;
    }, 

    'empty': function(nodes,  value,  root) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++) {
        // IE treats comments as element nodes
        if (node.tagName == '!' || (node.firstChild && !node.innerHTML.match(/^\s*$/))) continue;
        results.push(node);
      }
      return results;
    }, 

    'not': function(nodes,  selector,  root) {
      var h = Selector.handlers,  selectorType,  m;
      var exclusions = new Selector(selector).findElements(root);
      h.mark(exclusions);
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        if (!node._countedByPrototype) results.push(node);
      h.unmark(exclusions);
      return results;
    }, 

    'enabled': function(nodes,  value,  root) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        if (!node.disabled) results.push(node);
      return results;
    }, 

    'disabled': function(nodes,  value,  root) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        if (node.disabled) results.push(node);
      return results;
    }, 

    'checked': function(nodes,  value,  root) {
      for (var i = 0,  results = [],  node; node = nodes[i]; i++)
        if (node.checked) results.push(node);
      return results;
    }
  }, 

  operators: {
    '=':  function(nv,  v) { return nv == v; }, 
    '!=': function(nv,  v) { return nv != v; }, 
    '^=': function(nv,  v) { return nv.startsWith(v); }, 
    '$=': function(nv,  v) { return nv.endsWith(v); }, 
    '*=': function(nv,  v) { return nv.include(v); }, 
    '~=': function(nv,  v) { return (' ' + nv + ' ').include(' ' + v + ' '); }, 
    '|=': function(nv,  v) { return ('-' + nv.toUpperCase() + '-').include('-' + v.toUpperCase() + '-'); }
  }, 

  split: function(expression) {
    var expressions = [];
    expression.scan(/(([\w#:.~>+()\s-]+|\*|\[.*?\])+)\s*(, |$)/,  function(m) {
      expressions.push(m[1].strip());
    });
    return expressions;
  }, 

  matchElements: function(elements,  expression) {
    var matches = $$(expression),  h = Selector.handlers;
    h.mark(matches);
    for (var i = 0,  results = [],  element; element = elements[i]; i++)
      if (element._countedByPrototype) results.push(element);
    h.unmark(matches);
    return results;
  }, 

  findElement: function(elements,  expression,  index) {
    if (Object.isNumber(expression)) {
      index = expression; expression = false;
    }
    return Selector.matchElements(elements,  expression || '*')[index || 0];
  }, 

  findChildElements: function(element,  expressions) {
    expressions = Selector.split(expressions.join(', '));
    var results = [],  h = Selector.handlers;
    for (var i = 0,  l = expressions.length,  selector; i < l; i++) {
      selector = new Selector(expressions[i].strip());
      h.concat(results,  selector.findElements(element));
    }
    return (l > 1) ? h.unique(results) : results;
  }
});

if (Prototype.Browser.IE) {
  Object.extend(Selector.handlers,  {
    // IE returns comment nodes on getElementsByTagName("*").
    // Filter them out.
    concat: function(a,  b) {
      for (var i = 0,  node; node = b[i]; i++)
        if (node.tagName !== "!") a.push(node);
      return a;
    }, 

    // IE improperly serializes _countedByPrototype in (inner|outer)HTML.
    unmark: function(nodes) {
      for (var i = 0,  node; node = nodes[i]; i++)
        node.removeAttribute('_countedByPrototype');
      return nodes;
    }
  });
}

function $$() {
  return Selector.findChildElements(document,  $A(arguments));
}
var Form = {
  reset: function(form) {
    $(form).reset();
    return form;
  }, 

  serializeElements: function(elements,  options) {
    if (typeof options != 'object') options = { hash: !!options };
    else if (Object.isUndefined(options.hash)) options.hash = true;
    var key,  value,  submitted = false,  submit = options.submit;

    var data = elements.inject({ },  function(result,  element) {
      if (!element.disabled && element.name) {
        key = element.name; value = $(element).getValue();
        if (value != null && (element.type != 'submit' || (!submitted &&
            submit !== false && (!submit || key == submit) && (submitted = true)))) {
          if (key in result) {
            // a key is already present; construct an array of values
            if (!Object.isArray(result[key])) result[key] = [result[key]];
            result[key].push(value);
          }
          else result[key] = value;
        }
      }
      return result;
    });

    return options.hash ? data : Object.toQueryString(data);
  }
};

Form.Methods = {
  serialize: function(form,  options) {
    return Form.serializeElements(Form.getElements(form),  options);
  }, 

  getElements: function(form) {
    return $A($(form).getElementsByTagName('*')).inject([], 
      function(elements,  child) {
        if (Form.Element.Serializers[child.tagName.toLowerCase()])
          elements.push(Element.extend(child));
        return elements;
      }
    );
  }, 

  getInputs: function(form,  typeName,  name) {
    form = $(form);
    var inputs = form.getElementsByTagName('input');

    if (!typeName && !name) return $A(inputs).map(Element.extend);

    for (var i = 0,  matchingInputs = [],  length = inputs.length; i < length; i++) {
      var input = inputs[i];
      if ((typeName && input.type != typeName) || (name && input.name != name))
        continue;
      matchingInputs.push(Element.extend(input));
    }

    return matchingInputs;
  }, 

  disable: function(form) {
    form = $(form);
    Form.getElements(form).invoke('disable');
    return form;
  }, 

  enable: function(form) {
    form = $(form);
    Form.getElements(form).invoke('enable');
    return form;
  }, 

  findFirstElement: function(form) {
    var elements = $(form).getElements().findAll(function(element) {
      return 'hidden' != element.type && !element.disabled;
    });
    var firstByIndex = elements.findAll(function(element) {
      return element.hasAttribute('tabIndex') && element.tabIndex >= 0;
    }).sortBy(function(element) { return element.tabIndex }).first();

    return firstByIndex ? firstByIndex : elements.find(function(element) {
      return ['input',  'select',  'textarea'].include(element.tagName.toLowerCase());
    });
  }, 

  focusFirstElement: function(form) {
    form = $(form);
    form.findFirstElement().activate();
    return form;
  }, 

  request: function(form,  options) {
    form = $(form),  options = Object.clone(options || { });

    var params = options.parameters,  action = form.readAttribute('action') || '';
    if (action.blank()) action = window.location.href;
    options.parameters = form.serialize(true);

    if (params) {
      if (Object.isString(params)) params = params.toQueryParams();
      Object.extend(options.parameters,  params);
    }

    if (form.hasAttribute('method') && !options.method)
      options.method = form.method;

    return new Ajax.Request(action,  options);
  }
};

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

Form.Element = {
  focus: function(element) {
    $(element).focus();
    return element;
  }, 

  select: function(element) {
    $(element).select();
    return element;
  }
};

Form.Element.Methods = {
  serialize: function(element) {
    element = $(element);
    if (!element.disabled && element.name) {
      var value = element.getValue();
      if (value != undefined) {
        var pair = { };
        pair[element.name] = value;
        return Object.toQueryString(pair);
      }
    }
    return '';
  }, 

  getValue: function(element) {
    element = $(element);
    var method = element.tagName.toLowerCase();
    return Form.Element.Serializers[method](element);
  }, 

  setValue: function(element,  value) {
    element = $(element);
    var method = element.tagName.toLowerCase();
    Form.Element.Serializers[method](element,  value);
    return element;
  }, 

  clear: function(element) {
    $(element).value = '';
    return element;
  }, 

  present: function(element) {
    return $(element).value != '';
  }, 

  activate: function(element) {
    element = $(element);
    try {
      element.focus();
      if (element.select && (element.tagName.toLowerCase() != 'input' ||
          !['button',  'reset',  'submit'].include(element.type)))
        element.select();
    } catch (e) { }
    return element;
  }, 

  disable: function(element) {
    element = $(element);
    element.blur();
    element.disabled = true;
    return element;
  }, 

  enable: function(element) {
    element = $(element);
    element.disabled = false;
    return element;
  }
};

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

var Field = Form.Element;
var $F = Form.Element.Methods.getValue;

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

Form.Element.Serializers = {
  input: function(element,  value) {
    switch (element.type.toLowerCase()) {
      case 'checkbox':
      case 'radio':
        return Form.Element.Serializers.inputSelector(element,  value);
      default:
        return Form.Element.Serializers.textarea(element,  value);
    }
  }, 

  inputSelector: function(element,  value) {
    if (Object.isUndefined(value)) return element.checked ? element.value : null;
    else element.checked = !!value;
  }, 

  textarea: function(element,  value) {
    if (Object.isUndefined(value)) return element.value;
    else element.value = value;
  }, 

  select: function(element,  index) {
    if (Object.isUndefined(index))
      return this[element.type == 'select-one' ?
        'selectOne' : 'selectMany'](element);
    else {
      var opt,  value,  single = !Object.isArray(index);
      for (var i = 0,  length = element.length; i < length; i++) {
        opt = element.options[i];
        value = this.optionValue(opt);
        if (single) {
          if (value == index) {
            opt.selected = true;
            return;
          }
        }
        else opt.selected = index.include(value);
      }
    }
  }, 

  selectOne: function(element) {
    var index = element.selectedIndex;
    return index >= 0 ? this.optionValue(element.options[index]) : null;
  }, 

  selectMany: function(element) {
    var values,  length = element.length;
    if (!length) return null;

    for (var i = 0,  values = []; i < length; i++) {
      var opt = element.options[i];
      if (opt.selected) values.push(this.optionValue(opt));
    }
    return values;
  }, 

  optionValue: function(opt) {
    // extend element because hasAttribute may not be native
    return Element.extend(opt).hasAttribute('value') ? opt.value : opt.text;
  }
};

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

Abstract.TimedObserver = Class.create(PeriodicalExecuter,  {
  initialize: function($super,  element,  frequency,  callback) {
    $super(callback,  frequency);
    this.element   = $(element);
    this.lastValue = this.getValue();
  }, 

  execute: function() {
    var value = this.getValue();
    if (Object.isString(this.lastValue) && Object.isString(value) ?
        this.lastValue != value : String(this.lastValue) != String(value)) {
      this.callback(this.element,  value);
      this.lastValue = value;
    }
  }
});

Form.Element.Observer = Class.create(Abstract.TimedObserver,  {
  getValue: function() {
    return Form.Element.getValue(this.element);
  }
});

Form.Observer = Class.create(Abstract.TimedObserver,  {
  getValue: function() {
    return Form.serialize(this.element);
  }
});

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

Abstract.EventObserver = Class.create({
  initialize: function(element,  callback) {
    this.element  = $(element);
    this.callback = callback;

    this.lastValue = this.getValue();
    if (this.element.tagName.toLowerCase() == 'form')
      this.registerFormCallbacks();
    else
      this.registerCallback(this.element);
  }, 

  onElementEvent: function() {
    var value = this.getValue();
    if (this.lastValue != value) {
      this.callback(this.element,  value);
      this.lastValue = value;
    }
  }, 

  registerFormCallbacks: function() {
    Form.getElements(this.element).each(this.registerCallback,  this);
  }, 

  registerCallback: function(element) {
    if (element.type) {
      switch (element.type.toLowerCase()) {
        case 'checkbox':
        case 'radio':
          Event.observe(element,  'click',  this.onElementEvent.bind(this));
          break;
        default:
          Event.observe(element,  'change',  this.onElementEvent.bind(this));
          break;
      }
    }
  }
});

Form.Element.EventObserver = Class.create(Abstract.EventObserver,  {
  getValue: function() {
    return Form.Element.getValue(this.element);
  }
});

Form.EventObserver = Class.create(Abstract.EventObserver,  {
  getValue: function() {
    return Form.serialize(this.element);
  }
});
if (!window.Event) var Event = { };

Object.extend(Event,  {
  KEY_BACKSPACE: 8, 
  KEY_TAB:       9, 
  KEY_RETURN:   13, 
  KEY_ESC:      27, 
  KEY_LEFT:     37, 
  KEY_UP:       38, 
  KEY_RIGHT:    39, 
  KEY_DOWN:     40, 
  KEY_DELETE:   46, 
  KEY_HOME:     36, 
  KEY_END:      35, 
  KEY_PAGEUP:   33, 
  KEY_PAGEDOWN: 34, 
  KEY_INSERT:   45, 

  cache: { }, 

  relatedTarget: function(event) {
    var element;
    switch(event.type) {
      case 'mouseover': element = event.fromElement; break;
      case 'mouseout':  element = event.toElement;   break;
      default: return null;
    }
    return Element.extend(element);
  }
});

Event.Methods = (function() {
  var isButton;

  if (Prototype.Browser.IE) {
    var buttonMap = { 0: 1,  1: 4,  2: 2 };
    isButton = function(event,  code) {
      return event.button == buttonMap[code];
    };

  } else if (Prototype.Browser.WebKit) {
    isButton = function(event,  code) {
      switch (code) {
        case 0: return event.which == 1 && !event.metaKey;
        case 1: return event.which == 1 && event.metaKey;
        default: return false;
      }
    };

  } else {
    isButton = function(event,  code) {
      return event.which ? (event.which === code + 1) : (event.button === code);
    };
  }

  return {
    isLeftClick:   function(event) { return isButton(event,  0) }, 
    isMiddleClick: function(event) { return isButton(event,  1) }, 
    isRightClick:  function(event) { return isButton(event,  2) }, 

    element: function(event) {
      var node = Event.extend(event).target;
      return Element.extend(node.nodeType == Node.TEXT_NODE ? node.parentNode : node);
    }, 

    findElement: function(event,  expression) {
      var element = Event.element(event);
      if (!expression) return element;
      var elements = [element].concat(element.ancestors());
      return Selector.findElement(elements,  expression,  0);
    }, 

    pointer: function(event) {
      return {
        x: event.pageX || (event.clientX +
          (document.documentElement.scrollLeft || document.body.scrollLeft)), 
        y: event.pageY || (event.clientY +
          (document.documentElement.scrollTop || document.body.scrollTop))
      };
    }, 

    pointerX: function(event) { return Event.pointer(event).x }, 
    pointerY: function(event) { return Event.pointer(event).y }, 

    stop: function(event) {
      Event.extend(event);
      event.preventDefault();
      event.stopPropagation();
      event.stopped = true;
    }
  };
})();

Event.extend = (function() {
  var methods = Object.keys(Event.Methods).inject({ },  function(m,  name) {
    m[name] = Event.Methods[name].methodize();
    return m;
  });

  if (Prototype.Browser.IE) {
    Object.extend(methods,  {
      stopPropagation: function() { this.cancelBubble = true }, 
      preventDefault:  function() { this.returnValue = false }, 
      inspect: function() { return "[object Event]" }
    });

    return function(event) {
      if (!event) return false;
      if (event._extendedByPrototype) return event;

      event._extendedByPrototype = Prototype.emptyFunction;
      var pointer = Event.pointer(event);
      Object.extend(event,  {
        target: event.srcElement, 
        relatedTarget: Event.relatedTarget(event), 
        pageX:  pointer.x, 
        pageY:  pointer.y
      });
      return Object.extend(event,  methods);
    };

  } else {
    Event.prototype = Event.prototype || document.createEvent("HTMLEvents").__proto__;
    Object.extend(Event.prototype,  methods);
    return Prototype.K;
  }
})();

Object.extend(Event,  (function() {
  var cache = Event.cache;

  function getEventID(element) {
    if (element._prototypeEventID) return element._prototypeEventID[0];
    arguments.callee.id = arguments.callee.id || 1;
    return element._prototypeEventID = [++arguments.callee.id];
  }

  function getDOMEventName(eventName) {
    if (eventName && eventName.include(':')) return "dataavailable";
    return eventName;
  }

  function getCacheForID(id) {
    return cache[id] = cache[id] || { };
  }

  function getWrappersForEventName(id,  eventName) {
    var c = getCacheForID(id);
    return c[eventName] = c[eventName] || [];
  }

  function createWrapper(element,  eventName,  handler) {
    var id = getEventID(element);
    var c = getWrappersForEventName(id,  eventName);
    if (c.pluck("handler").include(handler)) return false;

    var wrapper = function(event) {
      if (!Event || !Event.extend ||
        (event.eventName && event.eventName != eventName))
          return false;

      Event.extend(event);
      handler.call(element,  event);
    };

    wrapper.handler = handler;
    c.push(wrapper);
    return wrapper;
  }

  function findWrapper(id,  eventName,  handler) {
    var c = getWrappersForEventName(id,  eventName);
    return c.find(function(wrapper) { return wrapper.handler == handler });
  }

  function destroyWrapper(id,  eventName,  handler) {
    var c = getCacheForID(id);
    if (!c[eventName]) return false;
    c[eventName] = c[eventName].without(findWrapper(id,  eventName,  handler));
  }

  function destroyCache() {
    for (var id in cache)
      for (var eventName in cache[id])
        cache[id][eventName] = null;
  }

  if (window.attachEvent) {
    window.attachEvent("onunload",  destroyCache);
  }

  return {
    observe: function(element,  eventName,  handler) {
      element = $(element);
      var name = getDOMEventName(eventName);

      var wrapper = createWrapper(element,  eventName,  handler);
      if (!wrapper) return element;

      if (element.addEventListener) {
        element.addEventListener(name,  wrapper,  false);
      } else {
        element.attachEvent("on" + name,  wrapper);
      }

      return element;
    }, 

    stopObserving: function(element,  eventName,  handler) {
      element = $(element);
      var id = getEventID(element),  name = getDOMEventName(eventName);

      if (!handler && eventName) {
        getWrappersForEventName(id,  eventName).each(function(wrapper) {
          element.stopObserving(eventName,  wrapper.handler);
        });
        return element;

      } else if (!eventName) {
        Object.keys(getCacheForID(id)).each(function(eventName) {
          element.stopObserving(eventName);
        });
        return element;
      }

      var wrapper = findWrapper(id,  eventName,  handler);
      if (!wrapper) return element;

      if (element.removeEventListener) {
        element.removeEventListener(name,  wrapper,  false);
      } else {
        element.detachEvent("on" + name,  wrapper);
      }

      destroyWrapper(id,  eventName,  handler);

      return element;
    }, 

    fire: function(element,  eventName,  memo) {
      element = $(element);
      if (element == document && document.createEvent && !element.dispatchEvent)
        element = document.documentElement;

      var event;
      if (document.createEvent) {
        event = document.createEvent("HTMLEvents");
        event.initEvent("dataavailable",  true,  true);
      } else {
        event = document.createEventObject();
        event.eventType = "ondataavailable";
      }

      event.eventName = eventName;
      event.memo = memo || { };

      if (document.createEvent) {
        element.dispatchEvent(event);
      } else {
        element.fireEvent(event.eventType,  event);
      }

      return Event.extend(event);
    }
  };
})());

Object.extend(Event,  Event.Methods);

Element.addMethods({
  fire:          Event.fire, 
  observe:       Event.observe, 
  stopObserving: Event.stopObserving
});

Object.extend(document,  {
  fire:          Element.Methods.fire.methodize(), 
  observe:       Element.Methods.observe.methodize(), 
  stopObserving: Element.Methods.stopObserving.methodize(), 
  loaded:        false
});

(function() {
  /* Support for the DOMContentLoaded event is based on work by Dan Webb, 
     Matthias Miller,  Dean Edwards and John Resig. */

  var timer;

  function fireContentLoadedEvent() {
    if (document.loaded) return;
    if (timer) window.clearInterval(timer);
    document.fire("dom:loaded");
    document.loaded = true;
  }

  if (document.addEventListener) {
    if (Prototype.Browser.WebKit) {
      timer = window.setInterval(function() {
        if (/loaded|complete/.test(document.readyState))
          fireContentLoadedEvent();
      },  0);

      Event.observe(window,  "load",  fireContentLoadedEvent);

    } else {
      document.addEventListener("DOMContentLoaded", 
        fireContentLoadedEvent,  false);
    }

  } else {
    document.write("<script id=__onDOMContentLoaded defer src=//:><\/script>");
    $("__onDOMContentLoaded").onreadystatechange = function() {
      if (this.readyState == "complete") {
        this.onreadystatechange = null;
        fireContentLoadedEvent();
      }
    };
  }
})();
/*------------------------------- DEPRECATED -------------------------------*/

Hash.toQueryString = Object.toQueryString;

var Toggle = { display: Element.toggle };

Element.Methods.childOf = Element.Methods.descendantOf;

var Insertion = {
  Before: function(element,  content) {
    return Element.insert(element,  {before:content});
  }, 

  Top: function(element,  content) {
    return Element.insert(element,  {top:content});
  }, 

  Bottom: function(element,  content) {
    return Element.insert(element,  {bottom:content});
  }, 

  After: function(element,  content) {
    return Element.insert(element,  {after:content});
  }
};

var $continue = new Error('"throw $continue" is deprecated,  use "return" instead');

// This should be moved to script.aculo.us; notice the deprecated methods
// further below,  that map to the newer Element methods.
var Position = {
  // set to true if needed,  warning: firefox performance problems
  // NOT neeeded for page scrolling,  only if draggable contained in
  // scrollable elements
  includeScrollOffsets: false, 

  // must be called before calling withinIncludingScrolloffset,  every time the
  // page is scrolled
  prepare: function() {
    this.deltaX =  window.pageXOffset
                || document.documentElement.scrollLeft
                || document.body.scrollLeft
                || 0;
    this.deltaY =  window.pageYOffset
                || document.documentElement.scrollTop
                || document.body.scrollTop
                || 0;
  }, 

  // caches x/y coordinate pair to use with overlap
  within: function(element,  x,  y) {
    if (this.includeScrollOffsets)
      return this.withinIncludingScrolloffsets(element,  x,  y);
    this.xcomp = x;
    this.ycomp = y;
    this.offset = Element.cumulativeOffset(element);

    return (y >= this.offset[1] &&
            y <  this.offset[1] + element.offsetHeight &&
            x >= this.offset[0] &&
            x <  this.offset[0] + element.offsetWidth);
  }, 

  withinIncludingScrolloffsets: function(element,  x,  y) {
    var offsetcache = Element.cumulativeScrollOffset(element);

    this.xcomp = x + offsetcache[0] - this.deltaX;
    this.ycomp = y + offsetcache[1] - this.deltaY;
    this.offset = Element.cumulativeOffset(element);

    return (this.ycomp >= this.offset[1] &&
            this.ycomp <  this.offset[1] + element.offsetHeight &&
            this.xcomp >= this.offset[0] &&
            this.xcomp <  this.offset[0] + element.offsetWidth);
  }, 

  // within must be called directly before
  overlap: function(mode,  element) {
    if (!mode) return 0;
    if (mode == 'vertical')
      return ((this.offset[1] + element.offsetHeight) - this.ycomp) /
        element.offsetHeight;
    if (mode == 'horizontal')
      return ((this.offset[0] + element.offsetWidth) - this.xcomp) /
        element.offsetWidth;
  }, 

  // Deprecation layer -- use newer Element methods now (1.5.2).

  cumulativeOffset: Element.Methods.cumulativeOffset, 

  positionedOffset: Element.Methods.positionedOffset, 

  absolutize: function(element) {
    Position.prepare();
    return Element.absolutize(element);
  }, 

  relativize: function(element) {
    Position.prepare();
    return Element.relativize(element);
  }, 

  realOffset: Element.Methods.cumulativeScrollOffset, 

  offsetParent: Element.Methods.getOffsetParent, 

  page: Element.Methods.viewportOffset, 

  clone: function(source,  target,  options) {
    options = options || { };
    return Element.clonePosition(target,  source,  options);
  }
};

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

if (!document.getElementsByClassName) document.getElementsByClassName = function(instanceMethods){
  function iter(name) {
    return name.blank() ? null : "[contains(concat(' ',  @class,  ' '),  ' " + name + " ')]";
  }

  instanceMethods.getElementsByClassName = Prototype.BrowserFeatures.XPath ?
  function(element,  className) {
    className = className.toString().strip();
    var cond = /\s/.test(className) ? $w(className).map(iter).join('') : iter(className);
    return cond ? document._getElementsByXPath('.//*' + cond,  element) : [];
  } : function(element,  className) {
    className = className.toString().strip();
    var elements = [],  classNames = (/\s/.test(className) ? $w(className) : null);
    if (!classNames && !className) return elements;

    var nodes = $(element).getElementsByTagName('*');
    className = ' ' + className + ' ';

    for (var i = 0,  child,  cn; child = nodes[i]; i++) {
      if (child.className && (cn = ' ' + child.className + ' ') && (cn.include(className) ||
          (classNames && classNames.all(function(name) {
            return !name.toString().blank() && cn.include(' ' + name + ' ');
          }))))
        elements.push(Element.extend(child));
    }
    return elements;
  };

  return function(className,  parentElement) {
    return $(parentElement || document.body).getElementsByClassName(className);
  };
}(Element.Methods);

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

Element.ClassNames = Class.create();
Element.ClassNames.prototype = {
  initialize: function(element) {
    this.element = $(element);
  }, 

  _each: function(iterator) {
    this.element.className.split(/\s+/).select(function(name) {
      return name.length > 0;
    })._each(iterator);
  }, 

  set: function(className) {
    this.element.className = className;
  }, 

  add: function(classNameToAdd) {
    if (this.include(classNameToAdd)) return;
    this.set($A(this).concat(classNameToAdd).join(' '));
  }, 

  remove: function(classNameToRemove) {
    if (!this.include(classNameToRemove)) return;
    this.set($A(this).without(classNameToRemove).join(' '));
  }, 

  toString: function() {
    return $A(this).join(' ');
  }
};

Object.extend(Element.ClassNames.prototype,  Enumerable);

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

Element.addMethods();