/*  Prototype JavaScript framework, version 1.5.1_rc2
  *  (c) 2005-2007 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: '1.5.1_rc2',
   Version: '1.5.1',
 
   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
   },
   BrowserFeatures: {
     XPath: !!document.evaluate,
     ElementExtensions: !!window.HTMLElement,
     SpecificElementExtensions:
       (document.createElement('div').__proto__ !==
        document.createElement('form').__proto__)
   },
 
   ScriptFragment: '(?:<script.*?>)((\n|\r|.)*?)(?:<\/script>)',
   emptyFunction: function() {},
   K: function(x) { return x }
 }
 
 var Class = {
   create: function() {
     return function() {
       this.initialize.apply(this, arguments);
     }
   }
 }
 
 var Abstract = new Object();
 
 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 === undefined) return 'undefined';
       if (object === null) return 'null';
       return object.inspect ? object.inspect() : object.toString();
     } 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.ownerDocument === document) return;
     var results = [];
     for (var property in object) {
       var value = Object.toJSON(object[property]);
       if (value !== undefined)
         results.push(property.toJSON() + ':' + value);
     }
     return '{' + results.join(',') + '}';
   },
 
   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);
   }
 });
 
 Function.prototype.bind = function() {
   var __method = this, args = $A(arguments), object = args.shift();
   return function() {
     return __method.apply(object, args.concat($A(arguments)));
   }
 }
 
 Function.prototype.bindAsEventListener = function(object) {
   var __method = this, args = $A(arguments), object = args.shift();
   return function(event) {
     return __method.apply(object, [( event || window.event)].concat(args).concat($A(arguments)));
   }
 }
 
 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';
   }
 });
 
 Date.prototype.toJSON = function() {
   return '"' + this.getFullYear() + '-' +
     (this.getMonth() + 1).toPaddedString(2) + '-' +
     this.getDate().toPaddedString(2) + 'T' +
     this.getHours().toPaddedString(2) + ':' +
     this.getMinutes().toPaddedString(2) + ':' +
     this.getSeconds().toPaddedString(2) + '"';
 };
 
 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;
   }
 }
 
 /*--------------------------------------------------------------------------*/
 
 var PeriodicalExecuter = Class.create();
 PeriodicalExecuter.prototype = {
   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);
   },
 
   stop: function() {
     if (!this.timer) return;
     clearInterval(this.timer);
     this.timer = null;
   },
 
   onTimerEvent: function() {
     if (!this.currentlyExecuting) {
       try {
         this.currentlyExecuting = true;
         this.callback(this);
       } 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 = count === undefined ? 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 this;
   },
 
   truncate: function(length, truncation) {
     length = length || 30;
     truncation = truncation === undefined ? '...' : truncation;
     return this.length > length ?
       this.slice(0, length - truncation.length) + truncation : 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 = document.createElement('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 name = decodeURIComponent(pair[0]);
         var value = pair[1] ? decodeURIComponent(pair[1]) : undefined;
 
         if (hash[name] !== undefined) {
           if (hash[name].constructor != Array)
             hash[name] = [hash[name]];
           if (value) hash[name].push(value);
         }
         else hash[name] = 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) {
     var result = '';
     for (var i = 0; i < count; i++) result += this;
     return result;
   },
 
   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);
   },
 
   evalJSON: function(sanitize) {
     try {
       if (!sanitize || (/^("(\\.|[^"\\\n\r])*?"|[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t])+?$/.test(this)))
         return eval('(' + this + ')');
     } catch (e) {}
     throw new SyntaxError('Badly formated JSON string: ' + this.inspect());
   },
 
   include: function(pattern) {
     return this.indexOf(pattern) > -1;
   },
 
   startsWith: function(pattern) {
     return this.indexOf(pattern) == 0;
   },
 
   endsWith: function(pattern) {
     return this.lastIndexOf(pattern) == (this.length - pattern.length);
   },
 
   empty: function() {
     return this == '';
   },
 
   blank: function() {
     return /^\s*$/.test(this);
   }
 });
 
 String.prototype.gsub.prepareReplacement = function(replacement) {
   if (typeof replacement == 'function') 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();
 Template.Pattern = /(^|.|\r|\n)(#\{(.*?)\})/;
 Template.prototype = {
   initialize: function(template, pattern) {
     this.template = template.toString();
     this.pattern  = pattern || Template.Pattern;
   },
 
   evaluate: function(object) {
     return this.template.gsub(this.pattern, function(match) {
       var before = match[1];
       if (before == '\\') return match[2];
       return before + String.interpret(object[match[3]]);
     });
   }
 }
 
 var $break    = new Object();
 var $continue = new Object();
 
 var Enumerable = {
   each: function(iterator) {
     var index = 0;
     try {
       this._each(function(value) {
         iterator(value, index++);
       });
     } catch (e) {
       if (e != $break) throw e;
     }
     return this;
   },
 
   eachSlice: function(number, iterator) {
     var index = -number, slices = [], array = this.toArray();
     while ((index += number) < array.length)
       slices.push(array.slice(index, index+number));
     return slices.map(iterator);
   },
 
   all: function(iterator) {
     var result = true;
     this.each(function(value, index) {
       result = result && !!(iterator || Prototype.K)(value, index);
       if (!result) throw $break;
     });
     return result;
   },
 
   any: function(iterator) {
     var result = false;
     this.each(function(value, index) {
       if (result = !!(iterator || Prototype.K)(value, index))
         throw $break;
     });
     return result;
   },
 
   collect: function(iterator) {
     var results = [];
     this.each(function(value, index) {
       results.push((iterator || Prototype.K)(value, index));
     });
     return results;
   },
 
   detect: function(iterator) {
     var result;
     this.each(function(value, index) {
       if (iterator(value, index)) {
         result = value;
         throw $break;
       }
     });
     return result;
   },
 
   findAll: function(iterator) {
     var results = [];
     this.each(function(value, index) {
       if (iterator(value, index))
         results.push(value);
     });
     return results;
   },
 
   grep: function(pattern, iterator) {
     var results = [];
     this.each(function(value, index) {
       var stringValue = value.toString();
       if (stringValue.match(pattern))
         results.push((iterator || Prototype.K)(value, index));
     })
     return results;
   },
 
   include: function(object) {
     var found = false;
     this.each(function(value) {
       if (value == object) {
         found = true;
         throw $break;
       }
     });
     return found;
   },
 
   inGroupsOf: function(number, fillWith) {
     fillWith = fillWith === undefined ? null : fillWith;
     return this.eachSlice(number, function(slice) {
       while(slice.length < number) slice.push(fillWith);
       return slice;
     });
   },
 
   inject: function(memo, iterator) {
     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) {
     var result;
     this.each(function(value, index) {
       value = (iterator || Prototype.K)(value, index);
       if (result == undefined || value >= result)
         result = value;
     });
     return result;
   },
 
   min: function(iterator) {
     var result;
     this.each(function(value, index) {
       value = (iterator || Prototype.K)(value, index);
       if (result == undefined || value < result)
         result = value;
     });
     return result;
   },
 
   partition: function(iterator) {
     var trues = [], falses = [];
     this.each(function(value, index) {
       ((iterator || Prototype.K)(value, index) ?
         trues : falses).push(value);
     });
     return [trues, falses];
   },
 
   pluck: function(property) {
     var results = [];
     this.each(function(value, index) {
       results.push(value[property]);
     });
     return results;
   },
 
   reject: function(iterator) {
     var results = [];
     this.each(function(value, index) {
       if (!iterator(value, index))
         results.push(value);
     });
     return results;
   },
 
   sortBy: function(iterator) {
     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 (typeof args.last() == 'function')
       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,
   member:  Enumerable.include,
   entries: Enumerable.toArray
 });
 var $A = Array.from = function(iterable) {
   if (!iterable) return [];
   if (iterable.toArray) {
     return iterable.toArray();
   } else {
     var results = [];
     for (var i = 0, length = iterable.length; i < length; i++)
       results.push(iterable[i]);
     return results;
   }
 }
 
 if (Prototype.Browser.WebKit) {
   $A = Array.from = function(iterable) {
     if (!iterable) return [];
     if (!(typeof iterable == 'function' && iterable == '[object NodeList]') &&
       iterable.toArray) {
       return iterable.toArray();
     } else {
       var results = [];
       for (var i = 0, length = iterable.length; i < length; i++)
         results.push(iterable[i]);
       return results;
     }
   }
 }
 
 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(value && value.constructor == Array ?
         value.flatten() : [value]);
     });
   },
 
   without: function() {
     var values = $A(arguments);
     return this.select(function(value) {
       return !values.include(value);
     });
   },
 
   indexOf: function(object) {
     for (var i = 0, length = this.length; i < length; i++)
       if (this[i] == object) return i;
     return -1;
   },
 
   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;
     });
   },
 
   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 (value !== undefined) results.push(value);
     });
     return '[' + results.join(',') + ']';
   }
 });
 
 Array.prototype.toArray = Array.prototype.clone;
 
 function $w(string) {
   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 (arguments[i].constructor == Array) {
         for (var j = 0, arrayLength = arguments[i].length; j < arrayLength; j++)
           array.push(arguments[i][j]);
       } else {
         array.push(arguments[i]);
       }
     }
     return array;
   }
 }
 var Hash = function(object) {
   if (object instanceof Hash) this.merge(object);
   else Object.extend(this, object || {});
 };
 
 Object.extend(Hash, {
   toQueryString: function(obj) {
     var parts = [];
     parts.add = arguments.callee.addPair;
 
     this.prototype._each.call(obj, function(pair) {
       if (!pair.key) return;
       var value = pair.value;
 
       if (value && typeof value == 'object') {
         if (value.constructor == Array) value.each(function(value) {
           parts.add(pair.key, value);
         });
         return;
       }
       parts.add(pair.key, value);
     });
 
     return parts.join('&');
   },
 
   toJSON: function(object) {
     var results = [];
     this.prototype._each.call(object, function(pair) {
       var value = Object.toJSON(pair.value);
       if (value !== undefined) results.push(pair.key.toJSON() + ':' + value);
     });
     return '{' + results.join(',') + '}';
   }
 });
 
 Hash.toQueryString.addPair = function(key, value, prefix) {
   if (value == null) return;
   key = encodeURIComponent(key);
   this.push(key + '=' + (value == null ? '' : encodeURIComponent(value)));
 }
 
 Object.extend(Hash.prototype, Enumerable);
 Object.extend(Hash.prototype, {
   _each: function(iterator) {
     for (var key in this) {
       var value = this[key];
       if (value && value == Hash.prototype[key]) continue;
 
       var pair = [key, value];
       pair.key = key;
       pair.value = value;
       iterator(pair);
     }
   },
 
   keys: function() {
     return this.pluck('key');
   },
 
   values: function() {
     return this.pluck('value');
   },
 
   merge: function(hash) {
     return $H(hash).inject(this, function(mergedHash, pair) {
       mergedHash[pair.key] = pair.value;
       return mergedHash;
     });
   },
 
   remove: function() {
     var result;
     for(var i = 0, length = arguments.length; i < length; i++) {
       var value = this[arguments[i]];
       if (value !== undefined){
         if (result === undefined) result = value;
         else {
           if (result.constructor != Array) result = [result];
           result.push(value)
         }
       }
       delete this[arguments[i]];
     }
     return result;
   },
 
   toQueryString: function() {
     return Hash.toQueryString(this);
   },
 
   inspect: function() {
     return '#<Hash:{' + this.map(function(pair) {
       return pair.map(Object.inspect).join(': ');
     }).join(', ') + '}>';
   },
 
   toJSON: function() {
     return Hash.toJSON(this);
   }
 });
 
 function $H(object) {
   if (object instanceof Hash) return object;
   return new Hash(object);
 };
 
 // Safari iterates over shadowed properties
 if (function() {
   var i = 0, Test = function(value) { this.key = value };
   Test.prototype.key = 'foo';
   for (var property in new Test('bar')) i++;
   return i > 1;
 }()) Hash.prototype._each = function(iterator) {
   var cache = [];
   for (var key in this) {
     var value = this[key];
     if ((value && value == Hash.prototype[key]) || cache.include(key)) continue;
     cache.push(key);
     var pair = [key, value];
     pair.key = key;
     pair.value = value;
     iterator(pair);
   }
 };
 ObjectRange = Class.create();
 Object.extend(ObjectRange.prototype, Enumerable);
 Object.extend(ObjectRange.prototype, {
   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 (typeof responder[callback] == 'function') {
         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 = function() {};
 Ajax.Base.prototype = {
   setOptions: function(options) {
     this.options = {
       method:       'post',
       asynchronous: true,
       contentType:  'application/x-www-form-urlencoded',
       encoding:     'UTF-8',
       parameters:   ''
     }
     Object.extend(this.options, options || {});
 
     this.options.method = this.options.method.toLowerCase();
     if (typeof this.options.parameters == 'string')
       this.options.parameters = this.options.parameters.toQueryParams();
   }
 }
 
 Ajax.Request = Class.create();
 Ajax.Request.Events =
   ['Uninitialized', 'Loading', 'Loaded', 'Interactive', 'Complete'];
 
 Ajax.Request.prototype = Object.extend(new Ajax.Base(), {
   _complete: false,
 
   initialize: function(url, options) {
     this.transport = Ajax.getTransport();
     this.setOptions(options);
     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 = Hash.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 {
       Ajax.Responders.dispatch('onCreate', this, this.transport);
 
       this.transport.open(this.method.toUpperCase(), this.url,
         this.options.asynchronous);
 
       if (this.options.asynchronous)
         setTimeout(function() { this.respondToReadyState(1) }.bind(this), 10);
 
       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 (typeof extras.push == 'function')
         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() {
     return !this.transport.status
         || (this.transport.status >= 200 && this.transport.status < 300);
   },
 
   respondToReadyState: function(readyState) {
     var state = Ajax.Request.Events[readyState];
     var transport = this.transport, json = this.evalJSON();
 
     if (state == 'Complete') {
       try {
         this._complete = true;
         (this.options['on' + this.transport.status]
          || this.options['on' + (this.success() ? 'Success' : 'Failure')]
          || Prototype.emptyFunction)(transport, json);
       } catch (e) {
         this.dispatchException(e);
       }
 
       if ((this.getHeader('Content-type') || 'text/javascript').strip().
         match(/^(text|application)\/(x-)?(java|ecma)script(;.*)?$/i))
           this.evalResponse();
     }
 
     try {
       (this.options['on' + state] || Prototype.emptyFunction)(transport, json);
       Ajax.Responders.dispatch('on' + state, this, transport, json);
     } catch (e) {
       this.dispatchException(e);
     }
 
     if (state == 'Complete') {
       // avoid memory leak in MSIE: clean up
       this.transport.onreadystatechange = Prototype.emptyFunction;
     }
   },
 
   getHeader: function(name) {
     try {
       return this.transport.getResponseHeader(name);
     } catch (e) { return null }
   },
 
   evalJSON: function() {
     try {
       var json = this.getHeader('X-JSON');
       return json ? eval('(' + json + ')') : null;
     } catch (e) { return null }
   },
 
   evalResponse: function() {
     try {
       return eval(this.transport.responseText);
     } catch (e) {
       this.dispatchException(e);
     }
   },
 
   dispatchException: function(exception) {
     (this.options.onException || Prototype.emptyFunction)(this, exception);
     Ajax.Responders.dispatch('onException', this, exception);
   }
 });
 
 Ajax.Updater = Class.create();
 
 Object.extend(Object.extend(Ajax.Updater.prototype, Ajax.Request.prototype), {
   initialize: function(container, url, options) {
     this.container = {
       success: (container.success || container),
       failure: (container.failure || (container.success ? null : container))
     }
 
     this.transport = Ajax.getTransport();
     this.setOptions(options);
 
     var onComplete = this.options.onComplete || Prototype.emptyFunction;
     this.options.onComplete = (function(transport, param) {
       this.updateContent();
       onComplete(transport, param);
     }).bind(this);
 
     this.request(url);
   },
 
   updateContent: function() {
     var receiver = this.container[this.success() ? 'success' : 'failure'];
     var response = this.transport.responseText;
 
     if (!this.options.evalScripts) response = response.stripScripts();
 
     if (receiver = $(receiver)) {
       if (this.options.insertion)
         new this.options.insertion(receiver, response);
       else
         receiver.update(response);
     }
 
     if (this.success()) {
       if (this.onComplete)
         setTimeout(this.onComplete.bind(this), 10);
     }
   }
 });
 
 Ajax.PeriodicalUpdater = Class.create();
 Ajax.PeriodicalUpdater.prototype = Object.extend(new Ajax.Base(), {
   initialize: function(container, url, options) {
     this.setOptions(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(request) {
     if (this.options.decay) {
       this.decay = (request.responseText == this.lastText ?
         this.decay * this.options.decay : 1);
 
       this.lastText = request.responseText;
     }
     this.timer = setTimeout(this.onTimerEvent.bind(this),
       this.decay * this.frequency * 1000);
   },
 
   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 (typeof element == 'string')
     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(query.snapshotItem(i));
     return results;
   };
 
   document.getElementsByClassName = function(className, parentElement) {
     var q = ".//*[contains(concat(' ', @class, ' '), ' " + className + " ')]";
     return document._getElementsByXPath(q, parentElement);
   }
 
 } else document.getElementsByClassName = function(className, parentElement) {
   var children = ($(parentElement) || document.body).getElementsByTagName('*');
   var elements = [], child;
   for (var i = 0, length = children.length; i < length; i++) {
     child = children[i];
     if (Element.hasClassName(child, className))
       elements.push(Element.extend(child));
   }
   return elements;
 };
 
 /*--------------------------------------------------------------------------*/
 
 if (!window.Element) var Element = {};
 
 Element.extend = function(element) {
   var F = Prototype.BrowserFeatures;
   if (!element || !element.tagName || element.nodeType == 3 ||
    element._extended || F.SpecificElementExtensions || element == window)
     return element;
 
   var methods = {}, tagName = element.tagName, cache = Element.extend.cache,
    T = Element.Methods.ByTag;
 
   // extend methods for all tags (Safari doesn't need this)
   if (!F.ElementExtensions) {
     Object.extend(methods, Element.Methods),
     Object.extend(methods, Element.Methods.Simulated);
   }
 
   // extend methods for specific tags
   if (T[tagName]) Object.extend(methods, T[tagName]);
 
   for (var property in methods) {
     var value = methods[property];
     if (typeof value == 'function' && !(property in element))
       element[property] = cache.findOrStore(value);
   }
 
   element._extended = Prototype.emptyFunction;
   return element;
 };
 
 Element.extend.cache = {
   findOrStore: function(value) {
     return this[value] = this[value] || function() {
       return value.apply(null, [this].concat($A(arguments)));
     }
   }
 };
 
 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, html) {
     html = typeof html == 'undefined' ? '' : html.toString();
     $(element).innerHTML = html.stripScripts();
     setTimeout(function() {html.evalScripts()}, 10);
     return element;
   },
 
   replace: function(element, html) {
     element = $(element);
     html = typeof html == 'undefined' ? '' : html.toString();
     if (element.outerHTML) {
       element.outerHTML = html.stripScripts();
     } else {
       var range = element.ownerDocument.createRange();
       range.selectNodeContents(element);
       element.parentNode.replaceChild(
         range.createContextualFragment(html.stripScripts()), element);
     }
     setTimeout(function() {html.evalScripts()}, 10);
     return element;
   },
 
   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 $A($(element).getElementsByTagName('*')).each(Element.extend);
   },
 
   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 (typeof selector == 'string')
       selector = new Selector(selector);
     return selector.match($(element));
   },
 
   up: function(element, expression, index) {
     var ancestors = $(element).ancestors();
     return expression ? Selector.findElement(ancestors, expression, index) :
       ancestors[index || 0];
   },
 
   down: function(element, expression, index) {
     var descendants = $(element).descendants();
     return expression ? Selector.findElement(descendants, expression, index) :
       descendants[index || 0];
   },
 
   previous: function(element, expression, index) {
     var previousSiblings = $(element).previousSiblings();
     return expression ? Selector.findElement(previousSiblings, expression, index) :
       previousSiblings[index || 0];
   },
 
   next: function(element, expression, index) {
     var nextSiblings = $(element).nextSiblings();
     return expression ? Selector.findElement(nextSiblings, expression, index) :
       nextSiblings[index || 0];
   },
 
   getElementsBySelector: function() {
     var args = $A(arguments), element = $(args.shift());
     return Selector.findChildElements(element, args);
   },
 
   getElementsByClassName: function(element, className) {
     return document.getElementsByClassName(className, element);
   },
 
   readAttribute: function(element, name) {
     element = $(element);
     if (Prototype.Browser.IE) {
       if (!element.attributes) return null;
       var t = Element._attributeTranslations;
       if (t.values[name]) return t.values[name](element, name);
       if (t.names[name])  name = t.names[name];
       var attribute = element.attributes[name];
       return attribute ? attribute.nodeValue : null;
     }
     return element.getAttribute(name);
   },
 
   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 = $(element))) return;
     var elementClassName = element.className;
     if (elementClassName.length == 0) return false;
     if (elementClassName == className ||
         elementClassName.match(new RegExp("(^|\\s)" + className + "(\\s|$)")))
       return true;
     return false;
   },
 
   addClassName: function(element, className) {
     if (!(element = $(element))) return;
     Element.classNames(element).add(className);
     return element;
   },
 
   removeClassName: function(element, className) {
     if (!(element = $(element))) return;
     Element.classNames(element).remove(className);
     return element;
   },
 
   toggleClassName: function(element, className) {
     if (!(element = $(element))) return;
     Element.classNames(element)[element.hasClassName(className) ? 'remove' : 'add'](className);
     return element;
   },
 
   observe: function() {
     Event.observe.apply(Event, arguments);
     return $A(arguments).first();
   },
 
   stopObserving: function() {
     Event.stopObserving.apply(Event, arguments);
     return $A(arguments).first();
   },
 
   // 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);
     while (element = element.parentNode)
       if (element == ancestor) return true;
     return false;
   },
 
   scrollTo: function(element) {
     element = $(element);
     var pos = Position.cumulativeOffset(element);
     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, camelized) {
     element = $(element);
     var elementStyle = element.style;
 
     for (var property in styles)
       if (property == 'opacity') element.setOpacity(styles[property])
       else
         elementStyle[(property == 'float' || property == 'cssFloat') ?
           (elementStyle.styleFloat === undefined ? 'cssFloat' : 'styleFloat') :
           (camelized ? property : property.camelize())] = 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.style.overflow || 'auto';
     if ((Element.getStyle(element, 'overflow') || 'visible') != '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;
   }
 };
 
 Object.extend(Element.Methods, {childOf: Element.Methods.descendantOf});
 
 if (Prototype.Browser.Opera) {
   Element.Methods._getStyle = Element.Methods.getStyle;
   Element.Methods.getStyle = function(element, style) {
     switch(style) {
       case 'left':
       case 'top':
       case 'right':
       case 'bottom':
         if (Element._getStyle(element, 'position') == 'static') return null;
       default: return Element._getStyle(element, style);
     }
   };
 }
 else if (Prototype.Browser.IE) {
   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) {
     element = $(element);
     var filter = element.getStyle('filter'), style = element.style;
     if (value == 1 || value === '') {
       style.filter = filter.replace(/alpha\([^\)]*\)/gi,'');
       return element;
     } else if (value < 0.00001) value = 0;
     style.filter = filter.replace(/alpha\([^\)]*\)/gi, '') +
       'alpha(opacity=' + (value * 100) + ')';
     return element;
   };
 
   // IE is missing .innerHTML support for TABLE-related elements
   Element.Methods.update = function(element, html) {
     element = $(element);
     html = typeof html == 'undefined' ? '' : html.toString();
     var tagName = element.tagName.toUpperCase();
     if (['THEAD','TBODY','TR','TD'].include(tagName)) {
       var div = document.createElement('div');
       switch (tagName) {
         case 'THEAD':
         case 'TBODY':
           div.innerHTML = '<table><tbody>' +  html.stripScripts() + '</tbody></table>';
           depth = 2;
           break;
         case 'TR':
           div.innerHTML = '<table><tbody><tr>' +  html.stripScripts() + '</tr></tbody></table>';
           depth = 3;
           break;
         case 'TD':
           div.innerHTML = '<table><tbody><tr><td>' +  html.stripScripts() + '</td></tr></tbody></table>';
           depth = 4;
       }
       $A(element.childNodes).each(function(node) { element.removeChild(node) });
       depth.times(function() { div = div.firstChild });
       $A(div.childNodes).each(function(node) { element.appendChild(node) });
     } else {
       element.innerHTML = html.stripScripts();
     }
     setTimeout(function() { html.evalScripts() }, 10);
     return element;
   }
 }
 else if (Prototype.Browser.Gecko) {
   Element.Methods.setOpacity = function(element, value) {
     element = $(element);
     element.style.opacity = (value == 1) ? 0.999999 :
       (value === '') ? '' : (value < 0.00001) ? 0 : value;
     return element;
   };
 }
 
 Element._attributeTranslations = {
   names: {
     colspan:   "colSpan",
     rowspan:   "rowSpan",
     valign:    "vAlign",
     datetime:  "dateTime",
     accesskey: "accessKey",
     tabindex:  "tabIndex",
     enctype:   "encType",
     maxlength: "maxLength",
     readonly:  "readOnly",
     longdesc:  "longDesc"
   },
   values: {
     _getAttr: function(element, attribute) {
       return element.getAttribute(attribute, 2);
     },
     _flag: function(element, attribute) {
       return $(element).hasAttribute(attribute) ? attribute : null;
     },
     style: function(element) {
       return element.style.cssText.toLowerCase();
     },
     title: function(element) {
       var node = element.getAttributeNode('title');
       return node.specified ? node.nodeValue : null;
     }
   }
 };
 
 (function() {
   Object.extend(this, {
     href: this._getAttr,
     src:  this._getAttr,
     disabled: this._flag,
     checked:  this._flag,
     readonly: this._flag,
     multiple: this._flag
   });
 }).call(Element._attributeTranslations.values);
 
 Element.Methods.Simulated = {
   hasAttribute: function(element, attribute) {
     var t = Element._attributeTranslations, node;
     attribute = t.names[attribute] || attribute;
     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.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 (arguments.length == 2) {
     var tagName = methods;
     methods = arguments[1];
   }
 
   if (!tagName) Object.extend(Element.Methods, methods || {});
   else {
     if (tagName.constructor == Array) 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;
     var cache = Element.extend.cache;
     for (var property in methods) {
       var value = methods[property];
       if (!onlyIfAbsent || !(property in destination))
         destination[property] = cache.findOrStore(value);
     }
   }
 
   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 (typeof klass == "undefined") continue;
       copy(T[tag], klass.prototype);
     }
   }
 };
 
 var Toggle = { display: Element.toggle };
 
 /*--------------------------------------------------------------------------*/
 
 Abstract.Insertion = function(adjacency) {
   this.adjacency = adjacency;
 }
 
 Abstract.Insertion.prototype = {
   initialize: function(element, content) {
     this.element = $(element);
     this.content = content.stripScripts();
 
     if (this.adjacency && this.element.insertAdjacentHTML) {
       try {
         this.element.insertAdjacentHTML(this.adjacency, this.content);
       } catch (e) {
         var tagName = this.element.tagName.toUpperCase();
         if (['TBODY', 'TR'].include(tagName)) {
           this.insertContent(this.contentFromAnonymousTable());
         } else {
           throw e;
         }
       }
     } else {
       this.range = this.element.ownerDocument.createRange();
       if (this.initializeRange) this.initializeRange();
       this.insertContent([this.range.createContextualFragment(this.content)]);
     }
 
     setTimeout(function() {content.evalScripts()}, 10);
   },
 
   contentFromAnonymousTable: function() {
     var div = document.createElement('div');
     div.innerHTML = '<table><tbody>' + this.content + '</tbody></table>';
     return $A(div.childNodes[0].childNodes[0].childNodes);
   }
 }
 
 var Insertion = new Object();
 
 Insertion.Before = Class.create();
 Insertion.Before.prototype = Object.extend(new Abstract.Insertion('beforeBegin'), {
   initializeRange: function() {
     this.range.setStartBefore(this.element);
   },
 
   insertContent: function(fragments) {
     fragments.each((function(fragment) {
       this.element.parentNode.insertBefore(fragment, this.element);
     }).bind(this));
   }
 });
 
 Insertion.Top = Class.create();
 Insertion.Top.prototype = Object.extend(new Abstract.Insertion('afterBegin'), {
   initializeRange: function() {
     this.range.selectNodeContents(this.element);
     this.range.collapse(true);
   },
 
   insertContent: function(fragments) {
     fragments.reverse(false).each((function(fragment) {
       this.element.insertBefore(fragment, this.element.firstChild);
     }).bind(this));
   }
 });
 
 Insertion.Bottom = Class.create();
 Insertion.Bottom.prototype = Object.extend(new Abstract.Insertion('beforeEnd'), {
   initializeRange: function() {
     this.range.selectNodeContents(this.element);
     this.range.collapse(this.element);
   },
 
   insertContent: function(fragments) {
     fragments.each((function(fragment) {
       this.element.appendChild(fragment);
     }).bind(this));
   }
 });
 
 Insertion.After = Class.create();
 Insertion.After.prototype = Object.extend(new Abstract.Insertion('afterEnd'), {
   initializeRange: function() {
     this.range.setStartAfter(this.element);
   },
 
   insertContent: function(fragments) {
     fragments.each((function(fragment) {
       this.element.parentNode.insertBefore(fragment,
         this.element.nextSibling);
     }).bind(this));
   }
 });
 
 /*--------------------------------------------------------------------------*/
 
 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);
 /* 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();
 
 Selector.prototype = {
   initialize: function(expression) {
     this.expression = expression.strip();
     this.compileMatcher();
   },
 
   compileMatcher: function() {
     // Selectors with namespaced attributes can't use the XPath version
     if (Prototype.BrowserFeatures.XPath && !(/\[[\w-]*?:/).test(this.expression))
       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(typeof c[i] == 'function' ? 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, p, 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(typeof x[i] == 'function' ? 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) {
     return this.findElements(document).include(element);
   },
 
   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: "[@#{1}]",
     attr: function(m) {
       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 (typeof h === 'function') 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) {
         if (!m[6]) return '';
         var p = Selector.patterns, x = Selector.xpath;
         for (var i in p) {
           if (mm = m[6].match(p[i])) {
             var ss = typeof x[i] == 'function' ? x[i](mm) : new Template(x[i]).evaluate(mm);
             m[6] = ss.substring(1, ss.length - 1);
             break;
           }
         }
         return "[not(" + m[6] + ")]";
       },
       '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(predicate, m) {
         var mm, formula = m[6];
         if (formula == 'even') formula = '2n+0';
         if (formula == 'odd')  formula = '2n+1';
         if (mm = formula.match(/^(\d+)$/)) // digit only
           predicate += "= " + mm[1];
         if (mm = formula.match(/^(\d+)?n(\+(\d+))?/)) { // an+b
           var a = mm[1] ? Number(mm[1]) : 1;
           var b = mm[3] ? Number(mm[3]) : 0;
           predicate += "mod " + a + " = " + b;
         }
         return "[" + predicate + "]";
       }
     }
   },
 
   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 = false;',
     attr: function(m) {
       m[3] = m[5] || m[6];
       return new Template('n = h.attr(n, r, "#{1}", "#{3}", "#{2}"); c = false;').evaluate(m);
     },
     pseudo:       'n = h.pseudo(n, "#{1}", "#{6}", r, c); c = false;',
     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|$)/,
     attrPresence: /^\[([\w]+)\]/,
     attr:         /\[((?:[\w-]*:)?[\w-]+)\s*(?:([!^$*~|]?=)\s*((['"])([^\]]*?)\4|([^'"][^\]]*?)))?\]/
   },
 
   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) {
       for (var i = 0, node; node = nodes[i]; i++)
         node._counted = true;
       return nodes;
     },
 
     unmark: function(nodes) {
       for (var i = 0, node; node = nodes[i]; i++)
         node._counted = 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._counted = true;
       if (reverse) {
         for (var nodes = parentNode.childNodes, i = nodes.length - 1, j = 1; i >= 0; i--) {
           node = nodes[i];
           if (node.nodeType == 1 && (!ofType || node._counted)) node.nodeIndex = j++;
         }
       } else {
         for (var i = 0, j = 1, nodes = parentNode.childNodes; node = nodes[i]; i++)
           if (node.nodeType == 1 && (!ofType || node._counted)) 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])._counted) {
           n._counted = true;
           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, Element.descendants(node));
       return results;
     },
 
     child: function(nodes) {
       var h = Selector.handlers;
       for (var i = 0, results = [], node; node = nodes[i]; i++)
         h.concat(results, Element.immediateDescendants(node));
       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) {
       tagName = 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() == tagName) results.push(node);
         return results;
       } else return root.getElementsByTagName(tagName);
     },
 
     id: function(nodes, root, id, combinator) {
       var targetNode = $(id), h = Selector.handlers;
       if (!nodes && root == document) return targetNode ? [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) {
       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) {
       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 (combinator) nodes = this[combinator](nodes);
       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 nth(-last)-child, nth(-last)-of-type, and (first|last)-of-type
     nth: function(nodes, formula, root, reverse, ofType) {
       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._counted) {
           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
         var a = m[1] ? Number(m[1]) : 1;
         var b = m[3] ? Number(m[3]) : 0;
         for (var i = 0, node; node = nodes[i]; i++)
           if (node.nodeIndex % a == b) 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, exclusions = $A(nodes), selectorType, m;
       for (var i in Selector.patterns) {
         if (m = selector.match(Selector.patterns[i])) {
           selectorType = i; break;
         }
       }
       switch(selectorType) {
         case 'className': case 'tagName': case 'id': // fallthroughs
         case 'attrPresence': exclusions = h[selectorType](exclusions, root, m[1], false); break;
         case 'attr': m[3] = m[5] || m[6]; exclusions = h.attr(exclusions, root, m[1], m[3], m[2]); break;
         case 'pseudo': exclusions = h.pseudo(exclusions, m[1], m[6], root, false); break;
         // only 'simple selectors' (one token) allowed in a :not clause
         default: throw 'Illegal selector in :not clause.';
       }
       h.mark(exclusions);
       for (var i = 0, results = [], node; node = nodes[i]; i++)
         if (!node._counted) 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() + '-'); }
   },
 
   matchElements: function(elements, expression) {
     var matches = new Selector(expression).findElements(), h = Selector.handlers;
     h.mark(matches);
     for (var i = 0, results = [], element; element = elements[i]; i++)
       if (element._counted) results.push(element);
     h.unmark(matches);
     return results;
   },
 
   findElement: function(elements, expression, index) {
     if (typeof expression == 'number') {
       index = expression; expression = false;
     }
     return Selector.matchElements(elements, expression || '*')[index || 0];
   },
 
   findChildElements: function(element, expressions) {
     var exprs = expressions.join(','), expressions = [];
     exprs.scan(/(([\w#:.~>+()\s-]+|\*|\[.*?\])+)\s*(,|$)/, function(m) {
       expressions.push(m[1].strip());
     });
     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;
   }
 });
 
 function $$() {
   return Selector.findChildElements(document, $A(arguments));
 }
 var Form = {
   reset: function(form) {
     $(form).reset();
     return form;
   },
 
   serializeElements: function(elements, getHash) {
     var data = elements.inject({}, function(result, element) {
       if (!element.disabled && element.name) {
         var key = element.name, value = $(element).getValue();
         if (value != null) {
             if (key in result) {
             if (result[key].constructor != Array) result[key] = [result[key]];
             result[key].push(value);
           }
           else result[key] = value;
         }
       }
       return result;
     });
 
     return getHash ? data : Hash.toQueryString(data);
   }
 };
 
 Form.Methods = {
   serialize: function(form, getHash) {
     return Form.serializeElements(Form.getElements(form), getHash);
   },
 
   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().each(function(element) {
       element.blur();
       element.disabled = 'true';
     });
     return form;
   },
 
   enable: function(form) {
     form = $(form);
     form.getElements().each(function(element) {
       element.disabled = '';
     });
     return form;
   },
 
   findFirstElement: function(form) {
     return $(form).getElements().find(function(element) {
       return element.type != 'hidden' && !element.disabled &&
         ['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;
     options.parameters = form.serialize(true);
 
     if (params) {
       if (typeof params == 'string') params = params.toQueryParams();
       Object.extend(options.parameters, params);
     }
 
     if (form.hasAttribute('method') && !options.method)
       options.method = form.method;
 
     return new Ajax.Request(form.action, options);
   }
 }
 
 Object.extend(Form, Form.Methods);
 
 /*--------------------------------------------------------------------------*/
 
 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 Hash.toQueryString(pair);
       }
     }
     return '';
   },
 
   getValue: function(element) {
     element = $(element);
     var method = element.tagName.toLowerCase();
     return Form.Element.Serializers[method](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;
   }
 }
 
 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)
 });
 
 /*--------------------------------------------------------------------------*/
 
 var Field = Form.Element;
 var $F = Form.Element.getValue;
 
 /*--------------------------------------------------------------------------*/
 
 Form.Element.Serializers = {
   input: function(element) {
     switch (element.type.toLowerCase()) {
       case 'checkbox':
       case 'radio':
         return Form.Element.Serializers.inputSelector(element);
       default:
         return Form.Element.Serializers.textarea(element);
     }
   },
 
   inputSelector: function(element) {
     return element.checked ? element.value : null;
   },
 
   textarea: function(element) {
     return element.value;
   },
 
   select: function(element) {
     return this[element.type == 'select-one' ?
       'selectOne' : 'selectMany'](element);
   },
 
   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 = function() {}
 Abstract.TimedObserver.prototype = {
   initialize: function(element, frequency, callback) {
     this.frequency = frequency;
     this.element   = $(element);
     this.callback  = callback;
 
     this.lastValue = this.getValue();
     this.registerCallback();
   },
 
   registerCallback: function() {
     setInterval(this.onTimerEvent.bind(this), this.frequency * 1000);
   },
 
   onTimerEvent: function() {
     var value = this.getValue();
     var changed = ('string' == typeof this.lastValue && 'string' == typeof value
       ? this.lastValue != value : String(this.lastValue) != String(value));
     if (changed) {
       this.callback(this.element, value);
       this.lastValue = value;
     }
   }
 }
 
 Form.Element.Observer = Class.create();
 Form.Element.Observer.prototype = Object.extend(new Abstract.TimedObserver(), {
   getValue: function() {
     return Form.Element.getValue(this.element);
   }
 });
 
 Form.Observer = Class.create();
 Form.Observer.prototype = Object.extend(new Abstract.TimedObserver(), {
   getValue: function() {
     return Form.serialize(this.element);
   }
 });
 
 /*--------------------------------------------------------------------------*/
 
 Abstract.EventObserver = function() {}
 Abstract.EventObserver.prototype = {
   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.bind(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();
 Form.Element.EventObserver.prototype = Object.extend(new Abstract.EventObserver(), {
   getValue: function() {
     return Form.Element.getValue(this.element);
   }
 });
 
 Form.EventObserver = Class.create();
 Form.EventObserver.prototype = Object.extend(new Abstract.EventObserver(), {
   getValue: function() {
     return Form.serialize(this.element);
   }
 });
 if (!window.Event) {
   var Event = new Object();
 }
 
 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,
 
   element: function(event) {
     return event.target || event.srcElement;
   },
 
   isLeftClick: function(event) {
     return (((event.which) && (event.which == 1)) ||
             ((event.button) && (event.button == 1)));
   },
 
   pointerX: function(event) {
     return event.pageX || (event.clientX +
       (document.documentElement.scrollLeft || document.body.scrollLeft));
   },
 
   pointerY: function(event) {
     return event.pageY || (event.clientY +
       (document.documentElement.scrollTop || document.body.scrollTop));
   },
 
   stop: function(event) {
     if (event.preventDefault) {
       event.preventDefault();
       event.stopPropagation();
     } else {
       event.returnValue = false;
       event.cancelBubble = true;
     }
   },
 
   // find the first node with the given tagName, starting from the
   // node the event was triggered on; traverses the DOM upwards
   findElement: function(event, tagName) {
     var element = Event.element(event);
     while (element.parentNode && (!element.tagName ||
         (element.tagName.toUpperCase() != tagName.toUpperCase())))
       element = element.parentNode;
     return element;
   },
 
   observers: false,
 
   _observeAndCache: function(element, name, observer, useCapture) {
     if (!this.observers) this.observers = [];
     if (element.addEventListener) {
       this.observers.push([element, name, observer, useCapture]);
       element.addEventListener(name, observer, useCapture);
     } else if (element.attachEvent) {
       this.observers.push([element, name, observer, useCapture]);
       element.attachEvent('on' + name, observer);
     }
   },
 
   unloadCache: function() {
     if (!Event.observers) return;
     for (var i = 0, length = Event.observers.length; i < length; i++) {
       Event.stopObserving.apply(this, Event.observers[i]);
       Event.observers[i][0] = null;
     }
     Event.observers = false;
   },
 
   observe: function(element, name, observer, useCapture) {
     element = $(element);
     useCapture = useCapture || false;
 
     if (name == 'keypress' &&
       (Prototype.Browser.WebKit || element.attachEvent))
       name = 'keydown';
 
     Event._observeAndCache(element, name, observer, useCapture);
   },
 
   stopObserving: function(element, name, observer, useCapture) {
     element = $(element);
     useCapture = useCapture || false;
 
     if (name == 'keypress' &&
         (Prototype.Browser.WebKit || element.attachEvent))
       name = 'keydown';
 
     if (element.removeEventListener) {
       element.removeEventListener(name, observer, useCapture);
     } else if (element.detachEvent) {
       try {
         element.detachEvent('on' + name, observer);
       } catch (e) {}
     }
   }
 });
 
 /* prevent memory leaks in IE */
 if (Prototype.Browser.IE)
   Event.observe(window, 'unload', Event.unloadCache, false);
 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;
   },
 
   realOffset: function(element) {
     var valueT = 0, valueL = 0;
     do {
       valueT += element.scrollTop  || 0;
       valueL += element.scrollLeft || 0;
       element = element.parentNode;
     } while (element);
     return [valueL, valueT];
   },
 
   cumulativeOffset: function(element) {
     var valueT = 0, valueL = 0;
     do {
       valueT += element.offsetTop  || 0;
       valueL += element.offsetLeft || 0;
       element = element.offsetParent;
     } while (element);
     return [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 == 'relative' || p == 'absolute') break;
       }
     } while (element);
     return [valueL, valueT];
   },
 
   offsetParent: 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;
   },
 
   // 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 = this.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 = this.realOffset(element);
 
     this.xcomp = x + offsetcache[0] - this.deltaX;
     this.ycomp = y + offsetcache[1] - this.deltaY;
     this.offset = this.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;
   },
 
   page: 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)
         if (Element.getStyle(element,'position')=='absolute') break;
 
     } while (element = element.offsetParent);
 
     element = forElement;
     do {
       if (!window.opera || element.tagName=='BODY') {
         valueT -= element.scrollTop  || 0;
         valueL -= element.scrollLeft || 0;
       }
     } while (element = element.parentNode);
 
     return [valueL, valueT];
   },
 
   clone: function(source, target) {
     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 = Position.page(source);
 
     // find coordinate system to use
     target = $(target);
     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(target,'position') == 'absolute') {
       parent = Position.offsetParent(target);
       delta = Position.page(parent);
     }
 
     // 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)   target.style.left  = (p[0] - delta[0] + options.offsetLeft) + 'px';
     if(options.setTop)    target.style.top   = (p[1] - delta[1] + options.offsetTop) + 'px';
     if(options.setWidth)  target.style.width = source.offsetWidth + 'px';
     if(options.setHeight) target.style.height = source.offsetHeight + 'px';
   },
 
   absolutize: function(element) {
     element = $(element);
     if (element.style.position == 'absolute') return;
     Position.prepare();
 
     var offsets = Position.positionedOffset(element);
     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';
   },
 
   relativize: function(element) {
     element = $(element);
     if (element.style.position == 'relative') return;
     Position.prepare();
 
     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;
   }
 }
 
 // Safari returns margins on body which is incorrect if the child is absolutely
 // positioned.  For performance reasons, redefine Position.cumulativeOffset for
 // KHTML/WebKit only.
 if (Prototype.Browser.WebKit) {
   Position.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 [valueL, valueT];
   }
 }
 
 Element.addMethods();