/* 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/') > -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', 'Interactive', '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();