/*  Prototype JavaScript framework, version 1.6.0.1
 *  (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: '1.6.0.1',

   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,
      MobileSafari: !!navigator.userAgent.match(/Apple.*Mobile.*Safari/)
   },

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

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

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

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


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

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

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

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

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

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

      klass.prototype.constructor = klass;

      return klass;
   }
};

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

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

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

      return this;
   }
};

var Abstract = { };

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

Object.extend(Object,{
   inspect: function(object) {
      try {
         if(Object.isUndefined(object)) return 'undefined';
         if(object === null) return 'null';
         return object.inspect ? object.inspect() : 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.isElement(object)) return;

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

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

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

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

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

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

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

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

   isArray: function(object) {
      return object && object.constructor === Array;
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      return returnValue;
   }
};

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

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

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

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

      this.registerCallback();
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      return camelized;
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

var $break = { };

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Array.from = $A;

Object.extend(Array.prototype,Enumerable);

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   activeRequestCount: 0
};

Ajax.Responders = {
   responders: [],

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

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

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

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

Object.extend(Ajax.Responders,Enumerable);

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

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

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

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

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

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

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

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

      this.parameters = params;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   status:      0,
   statusText: '',

   getStatus: Ajax.Request.prototype.getStatus,

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

   getHeader: Ajax.Request.prototype.getHeader,

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

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

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

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

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

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

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

      $super(url,options);
   },

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

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

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

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

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

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

      this.start();
   },

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

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

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

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

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

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

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

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

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

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

Element.cache = { };

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

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

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

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

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

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

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

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

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

      var content, insert, tagName, childNodes;

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

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

         content = Object.toHTML(content);

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

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

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

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

      return element;
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      return element;
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      return $(document.body);
   },

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

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

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

      } while(element = element.offsetParent);

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

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

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

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

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

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

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

Element.Methods.identify.counter = 1;

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

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

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

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

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

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

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

else if(Prototype.Browser.IE) {
   $w('positionedOffset getOffsetParent viewportOffset').each(function(method) {
      Element.Methods[method] = Element.Methods[method].wrap(
              function(proceed,element) {
                 element = $(element);
                 var position = element.getStyle('position');
                 if(position != 'static') return proceed(element);
                 element.setStyle({ position: 'relative' });
                 var value = proceed(element);
                 element.setStyle({ position: position });
                 return value;
              }
              );
   });

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

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

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

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

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

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

   Element._attributeTranslations.write = {
      names: Object.clone(Element._attributeTranslations.read.names),
      values: {
         checked: function(element,value) {
            element.checked = !!value;
         },

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

   Element._attributeTranslations.has = {};

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

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

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

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

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

      return element;
   };

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Element.Methods.ByTag = { };

Object.extend(Element,Element.Methods);

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

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

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

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

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

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

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

      element._extendedByPrototype = Prototype.emptyFunction;
      return element;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      var e = this.expression;

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

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

      return true;
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      return match;
   },

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

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

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

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

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

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

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

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

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

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

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

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

      attr: function(element,matches) {
         var nodeValue = Element.readAttribute(element,matches[1]);
         return Selector.operators[matches[2]](nodeValue,matches[3]);
      }
   },

   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--) {
               var 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,node.getElementsByTagName('*'));
         return results;
      },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      return matchingInputs;
   },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   cache: { },

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   function getEventID(element) {
      if(element._eventID) return element._eventID;
      arguments.callee.id = arguments.callee.id || 1;
      return element._eventID = ++arguments.callee.id;
   }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

         return element;
      },

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

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

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

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

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

         destroyWrapper(id,eventName,handler);

         return element;
      },

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

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

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

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

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

Object.extend(Event,Event.Methods);

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

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

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

   var timer;

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

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

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

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

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

Hash.toQueryString = Object.toQueryString;

var Toggle = { display: Element.toggle };

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   cumulativeOffset: Element.Methods.cumulativeOffset,

   positionedOffset: Element.Methods.positionedOffset,

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

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

   realOffset: Element.Methods.cumulativeScrollOffset,

   offsetParent: Element.Methods.getOffsetParent,

   page: Element.Methods.viewportOffset,

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Element.addMethods();