var Builder = {
    NODEMAP: {
        AREA: 'map',
        CAPTION: 'table',
        COL: 'table',
        COLGROUP: 'table',
        LEGEND: 'fieldset',
        OPTGROUP: 'select',
        OPTION: 'select',
        PARAM: 'object',
        TBODY: 'table',
        TD: 'table',
        TFOOT: 'table',
        TH: 'table',
        THEAD: 'table',
        TR: 'table'
    },
    // note: For Firefox < 1.5, OPTION and OPTGROUP tags are currently broken,
    //       due to a Firefox bug
    node: function(elementName) {
        elementName = elementName.toUpperCase();

        // try innerHTML approach
        var parentTag = this.NODEMAP[elementName] || 'div';
        var parentElement = document.createElement(parentTag);
        try { // prevent IE "feature": http://dev.rubyonrails.org/ticket/2707
            parentElement.innerHTML = "<" + elementName + "></" + elementName + ">";
        } catch (e) { }
        var element = parentElement.firstChild || null;

        // see if browser added wrapping tags
        if (element && (element.tagName.toUpperCase() != elementName))
            element = element.getElementsByTagName(elementName)[0];

        // fallback to createElement approach
        if (!element) element = document.createElement(elementName);

        // abort if nothing could be created
        if (!element) return;

        // attributes (or text)
        if (arguments[1])
            if (this._isStringOrNumber(arguments[1]) ||
        (arguments[1] instanceof Array) ||
        arguments[1].tagName) {
            this._children(element, arguments[1]);
        } else {
            var attrs = this._attributes(arguments[1]);
            if (attrs.length) {
                try { // prevent IE "feature": http://dev.rubyonrails.org/ticket/2707
                    parentElement.innerHTML = "<" + elementName + " " +
                attrs + "></" + elementName + ">";
                } catch (e) { }
                element = parentElement.firstChild || null;
                // workaround firefox 1.0.X bug
                if (!element) {
                    element = document.createElement(elementName);
                    for (attr in arguments[1])
                        element[attr == 'class' ? 'className' : attr] = arguments[1][attr];
                }
                if (element.tagName.toUpperCase() != elementName)
                    element = parentElement.getElementsByTagName(elementName)[0];
            }
        }

        // text, or array of children
        if (arguments[2])
            this._children(element, arguments[2]);

        return element;
    },
    _text: function(text) {
        return document.createTextNode(text);
    },

    ATTR_MAP: {
        'className': 'class',
        'htmlFor': 'for'
    },

    _attributes: function(attributes) {
        var attrs = [];
        for (attribute in attributes)
            attrs.push((attribute in this.ATTR_MAP ? this.ATTR_MAP[attribute] : attribute) +
          '="' + attributes[attribute].toString().escapeHTML().gsub(/"/, '&quot;') + '"');
        return attrs.join(" ");
    },
    _children: function(element, children) {
        if (children.tagName) {
            element.appendChild(children);
            return;
        }
        if (typeof children == 'object') { // array can hold nodes and text
            children.flatten().each(function(e) {
                if (typeof e == 'object')
                    element.appendChild(e)
                else
                    if (Builder._isStringOrNumber(e))
                    element.appendChild(Builder._text(e));
            });
        } else
            if (Builder._isStringOrNumber(children))
            element.appendChild(Builder._text(children));
    },
    _isStringOrNumber: function(param) {
        return (typeof param == 'string' || typeof param == 'number');
    },
    build: function(html) {
        var element = this.node('div');
        $(element).update(html.strip());
        return element.down();
    },
    dump: function(scope) {
        if (typeof scope != 'object' && typeof scope != 'function') scope = window; //global scope 

        var tags = ("A ABBR ACRONYM ADDRESS APPLET AREA B BASE BASEFONT BDO BIG BLOCKQUOTE BODY " +
      "BR BUTTON CAPTION CENTER CITE CODE COL COLGROUP DD DEL DFN DIR DIV DL DT EM FIELDSET " +
      "FONT FORM FRAME FRAMESET H1 H2 H3 H4 H5 H6 HEAD HR HTML I IFRAME IMG INPUT INS ISINDEX " +
      "KBD LABEL LEGEND LI LINK MAP MENU META NOFRAMES NOSCRIPT OBJECT OL OPTGROUP OPTION P " +
      "PARAM PRE Q S SAMP SCRIPT SELECT SMALL SPAN STRIKE STRONG STYLE SUB SUP TABLE TBODY TD " +
      "TEXTAREA TFOOT TH THEAD TITLE TR TT U UL VAR").split(/\s+/);

        tags.each(function(tag) {
            scope[tag] = function() {
                return Builder.node.apply(Builder, [tag].concat($A(arguments)));
            }
        });
    }
}
String.prototype.parseColor = function() {
    var color = '#';
    if (this.slice(0, 4) == 'rgb(') {
        var cols = this.slice(4, this.length - 1).split(',');
        var i = 0; do { color += parseInt(cols[i]).toColorPart() } while (++i < 3);
    } else {
        if (this.slice(0, 1) == '#') {
            if (this.length == 4) for (var i = 1; i < 4; i++) color += (this.charAt(i) + this.charAt(i)).toLowerCase();
            if (this.length == 7) color = this.toLowerCase();
        }
    }
    return (color.length == 7 ? color : (arguments[0] || this));
};

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

Element.collectTextNodes = function(element) {
    return $A($(element).childNodes).collect(function(node) {
        return (node.nodeType == 3 ? node.nodeValue :
      (node.hasChildNodes() ? Element.collectTextNodes(node) : ''));
    }).flatten().join('');
};

Element.collectTextNodesIgnoreClass = function(element, className) {
    return $A($(element).childNodes).collect(function(node) {
        return (node.nodeType == 3 ? node.nodeValue :
      ((node.hasChildNodes() && !Element.hasClassName(node, className)) ?
        Element.collectTextNodesIgnoreClass(node, className) : ''));
    }).flatten().join('');
};

Element.setContentZoom = function(element, percent) {
    element = $(element);
    element.setStyle({ fontSize: (percent / 100) + 'em' });
    if (Prototype.Browser.WebKit) window.scrollBy(0, 0);
    return element;
};

Element.getInlineOpacity = function(element) {
    return $(element).style.opacity || '';
};

Element.forceRerendering = function(element) {
    try {
        element = $(element);
        var n = document.createTextNode(' ');
        element.appendChild(n);
        element.removeChild(n);
    } catch (e) { }
};

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

var Effect = {
    _elementDoesNotExistError: {
        name: 'ElementDoesNotExistError',
        message: 'The specified DOM element does not exist, but is required for this effect to operate'
    },
    Transitions: {
        linear: Prototype.K,
        sinoidal: function(pos) {
            return (-Math.cos(pos * Math.PI) / 2) + 0.5;
        },
        reverse: function(pos) {
            return 1 - pos;
        },
        flicker: function(pos) {
            var pos = ((-Math.cos(pos * Math.PI) / 4) + 0.75) + Math.random() / 4;
            return pos > 1 ? 1 : pos;
        },
        wobble: function(pos) {
            return (-Math.cos(pos * Math.PI * (9 * pos)) / 2) + 0.5;
        },
        pulse: function(pos, pulses) {
            pulses = pulses || 5;
            return (
        ((pos % (1 / pulses)) * pulses).round() == 0 ?
              ((pos * pulses * 2) - (pos * pulses * 2).floor()) :
          1 - ((pos * pulses * 2) - (pos * pulses * 2).floor())
        );
        },
        spring: function(pos) {
            return 1 - (Math.cos(pos * 4.5 * Math.PI) * Math.exp(-pos * 6));
        },
        none: function(pos) {
            return 0;
        },
        full: function(pos) {
            return 1;
        }
    },
    DefaultOptions: {
        duration: 1.0,   // seconds
        fps: 100,   // 100= assume 66fps max.
        sync: false, // true for combining
        from: 0.0,
        to: 1.0,
        delay: 0.0,
        queue: 'parallel'
    },
    tagifyText: function(element) {
        var tagifyStyle = 'position:relative';
        if (Prototype.Browser.IE) tagifyStyle += ';zoom:1';

        element = $(element);
        $A(element.childNodes).each(function(child) {
            if (child.nodeType == 3) {
                child.nodeValue.toArray().each(function(character) {
                    element.insertBefore(
            new Element('span', { style: tagifyStyle }).update(
              character == ' ' ? String.fromCharCode(160) : character),
              child);
                });
                Element.remove(child);
            }
        });
    },
    multiple: function(element, effect) {
        var elements;
        if (((typeof element == 'object') ||
        Object.isFunction(element)) &&
       (element.length))
            elements = element;
        else
            elements = $(element).childNodes;

        var options = Object.extend({
            speed: 0.1,
            delay: 0.0
        }, arguments[2] || {});
        var masterDelay = options.delay;

        $A(elements).each(function(element, index) {
            new effect(element, Object.extend(options, { delay: index * options.speed + masterDelay }));
        });
    },
    PAIRS: {
        'slide': ['SlideDown', 'SlideUp'],
        'blind': ['BlindDown', 'BlindUp'],
        'appear': ['Appear', 'Fade']
    },
    toggle: function(element, effect) {
        element = $(element);
        effect = (effect || 'appear').toLowerCase();
        var options = Object.extend({
            queue: { position: 'end', scope: (element.id || 'global'), limit: 1 }
        }, arguments[2] || {});
        Effect[element.visible() ?
      Effect.PAIRS[effect][1] : Effect.PAIRS[effect][0]](element, options);
    }
};

Effect.DefaultOptions.transition = Effect.Transitions.sinoidal;

/* ------------- core effects ------------- */

Effect.ScopedQueue = Class.create(Enumerable, {
    initialize: function() {
        this.effects = [];
        this.interval = null;
    },
    _each: function(iterator) {
        this.effects._each(iterator);
    },
    add: function(effect) {
        var timestamp = new Date().getTime();

        var position = Object.isString(effect.options.queue) ?
      effect.options.queue : effect.options.queue.position;

        switch (position) {
            case 'front':
                // move unstarted effects after this effect  
                this.effects.findAll(function(e) { return e.state == 'idle' }).each(function(e) {
                    e.startOn += effect.finishOn;
                    e.finishOn += effect.finishOn;
                });
                break;
            case 'with-last':
                timestamp = this.effects.pluck('startOn').max() || timestamp;
                break;
            case 'end':
                // start effect after last queued effect has finished
                timestamp = this.effects.pluck('finishOn').max() || timestamp;
                break;
        }

        effect.startOn += timestamp;
        effect.finishOn += timestamp;

        if (!effect.options.queue.limit || (this.effects.length < effect.options.queue.limit))
            this.effects.push(effect);

        if (!this.interval)
            this.interval = setInterval(this.loop.bind(this), 15);
    },
    remove: function(effect) {
        this.effects = this.effects.reject(function(e) { return e == effect });
        if (this.effects.length == 0) {
            clearInterval(this.interval);
            this.interval = null;
        }
    },
    loop: function() {
        var timePos = new Date().getTime();
        for (var i = 0, len = this.effects.length; i < len; i++)
            this.effects[i] && this.effects[i].loop(timePos);
    }
});

Effect.Queues = {
    instances: $H(),
    get: function(queueName) {
        if (!Object.isString(queueName)) return queueName;

        return this.instances.get(queueName) ||
      this.instances.set(queueName, new Effect.ScopedQueue());
    }
};
Effect.Queue = Effect.Queues.get('global');

Effect.Base = Class.create({
    position: null,
    start: function(options) {
        function codeForEvent(options, eventName) {
            return (
        (options[eventName + 'Internal'] ? 'this.options.' + eventName + 'Internal(this);' : '') +
        (options[eventName] ? 'this.options.' + eventName + '(this);' : '')
      );
        }
        if (options && options.transition === false) options.transition = Effect.Transitions.linear;
        this.options = Object.extend(Object.extend({}, Effect.DefaultOptions), options || {});
        this.currentFrame = 0;
        this.state = 'idle';
        this.startOn = this.options.delay * 1000;
        this.finishOn = this.startOn + (this.options.duration * 1000);
        this.fromToDelta = this.options.to - this.options.from;
        this.totalTime = this.finishOn - this.startOn;
        this.totalFrames = this.options.fps * this.options.duration;

        eval('this.render = function(pos){ ' +
      'if (this.state=="idle"){this.state="running";' +
      codeForEvent(this.options, 'beforeSetup') +
      (this.setup ? 'this.setup();' : '') +
      codeForEvent(this.options, 'afterSetup') +
      '};if (this.state=="running"){' +
      'pos=this.options.transition(pos)*' + this.fromToDelta + '+' + this.options.from + ';' +
      'this.position=pos;' +
      codeForEvent(this.options, 'beforeUpdate') +
      (this.update ? 'this.update(pos);' : '') +
      codeForEvent(this.options, 'afterUpdate') +
      '}}');

        this.event('beforeStart');
        if (!this.options.sync)
            Effect.Queues.get(Object.isString(this.options.queue) ?
        'global' : this.options.queue.scope).add(this);
    },
    loop: function(timePos) {
        if (timePos >= this.startOn) {
            if (timePos >= this.finishOn) {
                this.render(1.0);
                this.cancel();
                this.event('beforeFinish');
                if (this.finish) this.finish();
                this.event('afterFinish');
                return;
            }
            var pos = (timePos - this.startOn) / this.totalTime,
          frame = (pos * this.totalFrames).round();
            if (frame > this.currentFrame) {
                this.render(pos);
                this.currentFrame = frame;
            }
        }
    },
    cancel: function() {
        if (!this.options.sync)
            Effect.Queues.get(Object.isString(this.options.queue) ?
        'global' : this.options.queue.scope).remove(this);
        this.state = 'finished';
    },
    event: function(eventName) {
        if (this.options[eventName + 'Internal']) this.options[eventName + 'Internal'](this);
        if (this.options[eventName]) this.options[eventName](this);
    },
    inspect: function() {
        var data = $H();
        for (property in this)
            if (!Object.isFunction(this[property])) data.set(property, this[property]);
        return '#<Effect:' + data.inspect() + ',options:' + $H(this.options).inspect() + '>';
    }
});

Effect.Parallel = Class.create(Effect.Base, {
    initialize: function(effects) {
        this.effects = effects || [];
        this.start(arguments[1]);
    },
    update: function(position) {
        this.effects.invoke('render', position);
    },
    finish: function(position) {
        this.effects.each(function(effect) {
            effect.render(1.0);
            effect.cancel();
            effect.event('beforeFinish');
            if (effect.finish) effect.finish(position);
            effect.event('afterFinish');
        });
    }
});

Effect.Tween = Class.create(Effect.Base, {
    initialize: function(object, from, to) {
        object = Object.isString(object) ? $(object) : object;
        var args = $A(arguments), method = args.last(),
      options = args.length == 5 ? args[3] : null;
        this.method = Object.isFunction(method) ? method.bind(object) :
      Object.isFunction(object[method]) ? object[method].bind(object) :
      function(value) { object[method] = value };
        this.start(Object.extend({ from: from, to: to }, options || {}));
    },
    update: function(position) {
        this.method(position);
    }
});

Effect.Event = Class.create(Effect.Base, {
    initialize: function() {
        this.start(Object.extend({ duration: 0 }, arguments[0] || {}));
    },
    update: Prototype.emptyFunction
});

Effect.Opacity = Class.create(Effect.Base, {
    initialize: function(element) {
        this.element = $(element);
        if (!this.element) throw (Effect._elementDoesNotExistError);
        // make this work on IE on elements without 'layout'
        if (Prototype.Browser.IE && (!this.element.currentStyle.hasLayout))
            this.element.setStyle({ zoom: 1 });
        var options = Object.extend({
            from: this.element.getOpacity() || 0.0,
            to: 1.0
        }, arguments[1] || {});
        this.start(options);
    },
    update: function(position) {
        this.element.setOpacity(position);
    }
});

Effect.Move = Class.create(Effect.Base, {
    initialize: function(element) {
        this.element = $(element);
        if (!this.element) throw (Effect._elementDoesNotExistError);
        var options = Object.extend({
            x: 0,
            y: 0,
            mode: 'relative'
        }, arguments[1] || {});
        this.start(options);
    },
    setup: function() {
        this.element.makePositioned();
        this.originalLeft = parseFloat(this.element.getStyle('left') || '0');
        this.originalTop = parseFloat(this.element.getStyle('top') || '0');
        if (this.options.mode == 'absolute') {
            this.options.x = this.options.x - this.originalLeft;
            this.options.y = this.options.y - this.originalTop;
        }
    },
    update: function(position) {
        this.element.setStyle({
            left: (this.options.x * position + this.originalLeft).round() + 'px',
            top: (this.options.y * position + this.originalTop).round() + 'px'
        });
    }
});

// for backwards compatibility
Effect.MoveBy = function(element, toTop, toLeft) {
    return new Effect.Move(element,
    Object.extend({ x: toLeft, y: toTop }, arguments[3] || {}));
};

Effect.Scale = Class.create(Effect.Base, {
    initialize: function(element, percent) {
        this.element = $(element);
        if (!this.element) throw (Effect._elementDoesNotExistError);
        var options = Object.extend({
            scaleX: true,
            scaleY: true,
            scaleContent: true,
            scaleFromCenter: false,
            scaleMode: 'box',        // 'box' or 'contents' or { } with provided values
            scaleFrom: 100.0,
            scaleTo: percent
        }, arguments[2] || {});
        this.start(options);
    },
    setup: function() {
        this.restoreAfterFinish = this.options.restoreAfterFinish || false;
        this.elementPositioning = this.element.getStyle('position');

        this.originalStyle = {};
        ['top', 'left', 'width', 'height', 'fontSize'].each(function(k) {
            this.originalStyle[k] = this.element.style[k];
        } .bind(this));

        this.originalTop = this.element.offsetTop;
        this.originalLeft = this.element.offsetLeft;

        var fontSize = this.element.getStyle('font-size') || '100%';
        ['em', 'px', '%', 'pt'].each(function(fontSizeType) {
            if (fontSize.indexOf(fontSizeType) > 0) {
                this.fontSize = parseFloat(fontSize);
                this.fontSizeType = fontSizeType;
            }
        } .bind(this));

        this.factor = (this.options.scaleTo - this.options.scaleFrom) / 100;

        this.dims = null;
        if (this.options.scaleMode == 'box')
            this.dims = [this.element.offsetHeight, this.element.offsetWidth];
        if (/^content/.test(this.options.scaleMode))
            this.dims = [this.element.scrollHeight, this.element.scrollWidth];
        if (!this.dims)
            this.dims = [this.options.scaleMode.originalHeight,
                   this.options.scaleMode.originalWidth];
    },
    update: function(position) {
        var currentScale = (this.options.scaleFrom / 100.0) + (this.factor * position);
        if (this.options.scaleContent && this.fontSize)
            this.element.setStyle({ fontSize: this.fontSize * currentScale + this.fontSizeType });
        this.setDimensions(this.dims[0] * currentScale, this.dims[1] * currentScale);
    },
    finish: function(position) {
        if (this.restoreAfterFinish) this.element.setStyle(this.originalStyle);
    },
    setDimensions: function(height, width) {
        var d = {};
        if (this.options.scaleX) d.width = width.round() + 'px';
        if (this.options.scaleY) d.height = height.round() + 'px';
        if (this.options.scaleFromCenter) {
            var topd = (height - this.dims[0]) / 2;
            var leftd = (width - this.dims[1]) / 2;
            if (this.elementPositioning == 'absolute') {
                if (this.options.scaleY) d.top = this.originalTop - topd + 'px';
                if (this.options.scaleX) d.left = this.originalLeft - leftd + 'px';
            } else {
                if (this.options.scaleY) d.top = -topd + 'px';
                if (this.options.scaleX) d.left = -leftd + 'px';
            }
        }
        this.element.setStyle(d);
    }
});

Effect.Highlight = Class.create(Effect.Base, {
    initialize: function(element) {
        this.element = $(element);
        if (!this.element) throw (Effect._elementDoesNotExistError);
        var options = Object.extend({ startcolor: '#ffff99' }, arguments[1] || {});
        this.start(options);
    },
    setup: function() {
        // Prevent executing on elements not in the layout flow
        if (this.element.getStyle('display') == 'none') { this.cancel(); return; }
        // Disable background image during the effect
        this.oldStyle = {};
        if (!this.options.keepBackgroundImage) {
            this.oldStyle.backgroundImage = this.element.getStyle('background-image');
            this.element.setStyle({ backgroundImage: 'none' });
        }
        if (!this.options.endcolor)
            this.options.endcolor = this.element.getStyle('background-color').parseColor('#ffffff');
        if (!this.options.restorecolor)
            this.options.restorecolor = this.element.getStyle('background-color');
        // init color calculations
        this._base = $R(0, 2).map(function(i) { return parseInt(this.options.startcolor.slice(i * 2 + 1, i * 2 + 3), 16) } .bind(this));
        this._delta = $R(0, 2).map(function(i) { return parseInt(this.options.endcolor.slice(i * 2 + 1, i * 2 + 3), 16) - this._base[i] } .bind(this));
    },
    update: function(position) {
        this.element.setStyle({ backgroundColor: $R(0, 2).inject('#', function(m, v, i) {
            return m + ((this._base[i] + (this._delta[i] * position)).round().toColorPart());
        } .bind(this))
        });
    },
    finish: function() {
        this.element.setStyle(Object.extend(this.oldStyle, {
            backgroundColor: this.options.restorecolor
        }));
    }
});

Effect.ScrollTo = function(element) {
    var options = arguments[1] || {},
    scrollOffsets = document.viewport.getScrollOffsets(),
    elementOffsets = $(element).cumulativeOffset(),
    max = (window.height || document.body.scrollHeight) - document.viewport.getHeight();

    if (options.offset) elementOffsets[1] += options.offset;

    return new Effect.Tween(null,
    scrollOffsets.top,
    elementOffsets[1] > max ? max : elementOffsets[1],
    options,
    function(p) { scrollTo(scrollOffsets.left, p.round()) }
  );
};

/* ------------- combination effects ------------- */

Effect.Fade = function(element) {
    element = $(element);
    var oldOpacity = element.getInlineOpacity();
    var options = Object.extend({
        from: element.getOpacity() || 1.0,
        to: 0.0,
        afterFinishInternal: function(effect) {
            if (effect.options.to != 0) return;
            effect.element.hide().setStyle({ opacity: oldOpacity });
        }
    }, arguments[1] || {});
    return new Effect.Opacity(element, options);
};

Effect.Appear = function(element) {
    element = $(element);
    var options = Object.extend({
        from: (element.getStyle('display') == 'none' ? 0.0 : element.getOpacity() || 0.0),
        to: 1.0,
        // force Safari to render floated elements properly
        afterFinishInternal: function(effect) {
            effect.element.forceRerendering();
        },
        beforeSetup: function(effect) {
            effect.element.setOpacity(effect.options.from).show();
        } 
    }, arguments[1] || {});
    return new Effect.Opacity(element, options);
};

Effect.Puff = function(element) {
    element = $(element);
    var oldStyle = {
        opacity: element.getInlineOpacity(),
        position: element.getStyle('position'),
        top: element.style.top,
        left: element.style.left,
        width: element.style.width,
        height: element.style.height
    };
    return new Effect.Parallel(
   [new Effect.Scale(element, 200,
      { sync: true, scaleFromCenter: true, scaleContent: true, restoreAfterFinish: true }),
     new Effect.Opacity(element, { sync: true, to: 0.0 })],
     Object.extend({ duration: 1.0,
         beforeSetupInternal: function(effect) {
             Position.absolutize(effect.effects[0].element)
         },
         afterFinishInternal: function(effect) {
             effect.effects[0].element.hide().setStyle(oldStyle);
         }
     }, arguments[1] || {})
   );
};

Effect.BlindUp = function(element) {
    element = $(element);
    element.makeClipping();
    return new Effect.Scale(element, 0,
    Object.extend({ scaleContent: false,
        scaleX: false,
        restoreAfterFinish: true,
        afterFinishInternal: function(effect) {
            effect.element.hide().undoClipping();
        }
    }, arguments[1] || {})
  );
};

Effect.BlindDown = function(element) {
    element = $(element);
    var elementDimensions = element.getDimensions();
    return new Effect.Scale(element, 100, Object.extend({
        scaleContent: false,
        scaleX: false,
        scaleFrom: 0,
        scaleMode: { originalHeight: elementDimensions.height, originalWidth: elementDimensions.width },
        restoreAfterFinish: true,
        afterSetup: function(effect) {
            effect.element.makeClipping().setStyle({ height: '0px' }).show();
        },
        afterFinishInternal: function(effect) {
            effect.element.undoClipping();
        }
    }, arguments[1] || {}));
};

Effect.SwitchOff = function(element) {
    element = $(element);
    var oldOpacity = element.getInlineOpacity();
    return new Effect.Appear(element, Object.extend({
        duration: 0.4,
        from: 0,
        transition: Effect.Transitions.flicker,
        afterFinishInternal: function(effect) {
            new Effect.Scale(effect.element, 1, {
                duration: 0.3, scaleFromCenter: true,
                scaleX: false, scaleContent: false, restoreAfterFinish: true,
                beforeSetup: function(effect) {
                    effect.element.makePositioned().makeClipping();
                },
                afterFinishInternal: function(effect) {
                    effect.element.hide().undoClipping().undoPositioned().setStyle({ opacity: oldOpacity });
                }
            })
        }
    }, arguments[1] || {}));
};

Effect.DropOut = function(element) {
    element = $(element);
    var oldStyle = {
        top: element.getStyle('top'),
        left: element.getStyle('left'),
        opacity: element.getInlineOpacity()
    };
    return new Effect.Parallel(
    [new Effect.Move(element, { x: 0, y: 100, sync: true }),
      new Effect.Opacity(element, { sync: true, to: 0.0 })],
    Object.extend(
      { duration: 0.5,
          beforeSetup: function(effect) {
              effect.effects[0].element.makePositioned();
          },
          afterFinishInternal: function(effect) {
              effect.effects[0].element.hide().undoPositioned().setStyle(oldStyle);
          }
      }, arguments[1] || {}));
};

Effect.Shake = function(element) {
    element = $(element);
    var options = Object.extend({
        distance: 20,
        duration: 0.5
    }, arguments[1] || {});
    var distance = parseFloat(options.distance);
    var split = parseFloat(options.duration) / 10.0;
    var oldStyle = {
        top: element.getStyle('top'),
        left: element.getStyle('left')
    };
    return new Effect.Move(element,
      { x: distance, y: 0, duration: split, afterFinishInternal: function(effect) {
          new Effect.Move(effect.element,
      { x: -distance * 2, y: 0, duration: split * 2, afterFinishInternal: function(effect) {
          new Effect.Move(effect.element,
      { x: distance * 2, y: 0, duration: split * 2, afterFinishInternal: function(effect) {
          new Effect.Move(effect.element,
      { x: -distance * 2, y: 0, duration: split * 2, afterFinishInternal: function(effect) {
          new Effect.Move(effect.element,
      { x: distance * 2, y: 0, duration: split * 2, afterFinishInternal: function(effect) {
          new Effect.Move(effect.element,
      { x: -distance, y: 0, duration: split, afterFinishInternal: function(effect) {
          effect.element.undoPositioned().setStyle(oldStyle);
      } 
      })
      } 
      })
      } 
      })
      } 
      })
      } 
      })
      } 
      });
};

Effect.SlideDown = function(element) {
    element = $(element).cleanWhitespace();
    // SlideDown need to have the content of the element wrapped in a container element with fixed height!
    var oldInnerBottom = element.down().getStyle('bottom');
    var elementDimensions = element.getDimensions();
    return new Effect.Scale(element, 100, Object.extend({
        scaleContent: false,
        scaleX: false,
        scaleFrom: window.opera ? 0 : 1,
        scaleMode: { originalHeight: elementDimensions.height, originalWidth: elementDimensions.width },
        restoreAfterFinish: true,
        afterSetup: function(effect) {
            effect.element.makePositioned();
            effect.element.down().makePositioned();
            if (window.opera) effect.element.setStyle({ top: '' });
            effect.element.makeClipping().setStyle({ height: '0px' }).show();
        },
        afterUpdateInternal: function(effect) {
            effect.element.down().setStyle({ bottom:
        (effect.dims[0] - effect.element.clientHeight) + 'px'
            });
        },
        afterFinishInternal: function(effect) {
            effect.element.undoClipping().undoPositioned();
            effect.element.down().undoPositioned().setStyle({ bottom: oldInnerBottom });
        }
    }, arguments[1] || {})
  );
};

Effect.SlideUp = function(element) {
    element = $(element).cleanWhitespace();
    var oldInnerBottom = element.down().getStyle('bottom');
    var elementDimensions = element.getDimensions();
    return new Effect.Scale(element, window.opera ? 0 : 1,
   Object.extend({ scaleContent: false,
       scaleX: false,
       scaleMode: 'box',
       scaleFrom: 100,
       scaleMode: { originalHeight: elementDimensions.height, originalWidth: elementDimensions.width },
       restoreAfterFinish: true,
       afterSetup: function(effect) {
           effect.element.makePositioned();
           effect.element.down().makePositioned();
           if (window.opera) effect.element.setStyle({ top: '' });
           effect.element.makeClipping().show();
       },
       afterUpdateInternal: function(effect) {
           effect.element.down().setStyle({ bottom:
        (effect.dims[0] - effect.element.clientHeight) + 'px'
           });
       },
       afterFinishInternal: function(effect) {
           effect.element.hide().undoClipping().undoPositioned();
           effect.element.down().undoPositioned().setStyle({ bottom: oldInnerBottom });
       }
   }, arguments[1] || {})
  );
};

// Bug in opera makes the TD containing this element expand for a instance after finish 
Effect.Squish = function(element) {
    return new Effect.Scale(element, window.opera ? 1 : 0, {
        restoreAfterFinish: true,
        beforeSetup: function(effect) {
            effect.element.makeClipping();
        },
        afterFinishInternal: function(effect) {
            effect.element.hide().undoClipping();
        }
    });
};

Effect.Grow = function(element) {
    element = $(element);
    var options = Object.extend({
        direction: 'center',
        moveTransition: Effect.Transitions.sinoidal,
        scaleTransition: Effect.Transitions.sinoidal,
        opacityTransition: Effect.Transitions.full
    }, arguments[1] || {});
    var oldStyle = {
        top: element.style.top,
        left: element.style.left,
        height: element.style.height,
        width: element.style.width,
        opacity: element.getInlineOpacity()
    };

    var dims = element.getDimensions();
    var initialMoveX, initialMoveY;
    var moveX, moveY;

    switch (options.direction) {
        case 'top-left':
            initialMoveX = initialMoveY = moveX = moveY = 0;
            break;
        case 'top-right':
            initialMoveX = dims.width;
            initialMoveY = moveY = 0;
            moveX = -dims.width;
            break;
        case 'bottom-left':
            initialMoveX = moveX = 0;
            initialMoveY = dims.height;
            moveY = -dims.height;
            break;
        case 'bottom-right':
            initialMoveX = dims.width;
            initialMoveY = dims.height;
            moveX = -dims.width;
            moveY = -dims.height;
            break;
        case 'center':
            initialMoveX = dims.width / 2;
            initialMoveY = dims.height / 2;
            moveX = -dims.width / 2;
            moveY = -dims.height / 2;
            break;
    }

    return new Effect.Move(element, {
        x: initialMoveX,
        y: initialMoveY,
        duration: 0.01,
        beforeSetup: function(effect) {
            effect.element.hide().makeClipping().makePositioned();
        },
        afterFinishInternal: function(effect) {
            new Effect.Parallel(
        [new Effect.Opacity(effect.element, { sync: true, to: 1.0, from: 0.0, transition: options.opacityTransition }),
          new Effect.Move(effect.element, { x: moveX, y: moveY, sync: true, transition: options.moveTransition }),
          new Effect.Scale(effect.element, 100, {
              scaleMode: { originalHeight: dims.height, originalWidth: dims.width },
              sync: true, scaleFrom: window.opera ? 1 : 0, transition: options.scaleTransition, restoreAfterFinish: true
          })
        ], Object.extend({
            beforeSetup: function(effect) {
                effect.effects[0].element.setStyle({ height: '0px' }).show();
            },
            afterFinishInternal: function(effect) {
                effect.effects[0].element.undoClipping().undoPositioned().setStyle(oldStyle);
            }
        }, options)
      )
        }
    });
};

Effect.Shrink = function(element) {
    element = $(element);
    var options = Object.extend({
        direction: 'center',
        moveTransition: Effect.Transitions.sinoidal,
        scaleTransition: Effect.Transitions.sinoidal,
        opacityTransition: Effect.Transitions.none
    }, arguments[1] || {});
    var oldStyle = {
        top: element.style.top,
        left: element.style.left,
        height: element.style.height,
        width: element.style.width,
        opacity: element.getInlineOpacity()
    };

    var dims = element.getDimensions();
    var moveX, moveY;

    switch (options.direction) {
        case 'top-left':
            moveX = moveY = 0;
            break;
        case 'top-right':
            moveX = dims.width;
            moveY = 0;
            break;
        case 'bottom-left':
            moveX = 0;
            moveY = dims.height;
            break;
        case 'bottom-right':
            moveX = dims.width;
            moveY = dims.height;
            break;
        case 'center':
            moveX = dims.width / 2;
            moveY = dims.height / 2;
            break;
    }

    return new Effect.Parallel(
    [new Effect.Opacity(element, { sync: true, to: 0.0, from: 1.0, transition: options.opacityTransition }),
      new Effect.Scale(element, window.opera ? 1 : 0, { sync: true, transition: options.scaleTransition, restoreAfterFinish: true }),
      new Effect.Move(element, { x: moveX, y: moveY, sync: true, transition: options.moveTransition })
    ], Object.extend({
        beforeStartInternal: function(effect) {
            effect.effects[0].element.makePositioned().makeClipping();
        },
        afterFinishInternal: function(effect) {
            effect.effects[0].element.hide().undoClipping().undoPositioned().setStyle(oldStyle);
        }
    }, options)
  );
};

Effect.Pulsate = function(element) {
    element = $(element);
    var options = arguments[1] || {};
    var oldOpacity = element.getInlineOpacity();
    var transition = options.transition || Effect.Transitions.sinoidal;
    var reverser = function(pos) { return transition(1 - Effect.Transitions.pulse(pos, options.pulses)) };
    reverser.bind(transition);
    return new Effect.Opacity(element,
    Object.extend(Object.extend({ duration: 2.0, from: 0,
        afterFinishInternal: function(effect) { effect.element.setStyle({ opacity: oldOpacity }); }
    }, options), { transition: reverser }));
};

Effect.Fold = function(element) {
    element = $(element);
    var oldStyle = {
        top: element.style.top,
        left: element.style.left,
        width: element.style.width,
        height: element.style.height
    };
    element.makeClipping();
    return new Effect.Scale(element, 5, Object.extend({
        scaleContent: false,
        scaleX: false,
        afterFinishInternal: function(effect) {
            new Effect.Scale(element, 1, {
                scaleContent: false,
                scaleY: false,
                afterFinishInternal: function(effect) {
                    effect.element.hide().undoClipping().setStyle(oldStyle);
                } 
            });
        } 
    }, arguments[1] || {}));
};

Effect.Morph = Class.create(Effect.Base, {
    initialize: function(element) {
        this.element = $(element);
        if (!this.element) throw (Effect._elementDoesNotExistError);
        var options = Object.extend({
            style: {}
        }, arguments[1] || {});

        if (!Object.isString(options.style)) this.style = $H(options.style);
        else {
            if (options.style.include(':'))
                this.style = options.style.parseStyle();
            else {
                this.element.addClassName(options.style);
                this.style = $H(this.element.getStyles());
                this.element.removeClassName(options.style);
                var css = this.element.getStyles();
                this.style = this.style.reject(function(style) {
                    return style.value == css[style.key];
                });
                options.afterFinishInternal = function(effect) {
                    effect.element.addClassName(effect.options.style);
                    effect.transforms.each(function(transform) {
                        effect.element.style[transform.style] = '';
                    });
                }
            }
        }
        this.start(options);
    },

    setup: function() {
        function parseColor(color) {
            if (!color || ['rgba(0, 0, 0, 0)', 'transparent'].include(color)) color = '#ffffff';
            color = color.parseColor();
            return $R(0, 2).map(function(i) {
                return parseInt(color.slice(i * 2 + 1, i * 2 + 3), 16)
            });
        }
        this.transforms = this.style.map(function(pair) {
            var property = pair[0], value = pair[1], unit = null;

            if (value.parseColor('#zzzzzz') != '#zzzzzz') {
                value = value.parseColor();
                unit = 'color';
            } else if (property == 'opacity') {
                value = parseFloat(value);
                if (Prototype.Browser.IE && (!this.element.currentStyle.hasLayout))
                    this.element.setStyle({ zoom: 1 });
            } else if (Element.CSS_LENGTH.test(value)) {
                var components = value.match(/^([\+\-]?[0-9\.]+)(.*)$/);
                value = parseFloat(components[1]);
                unit = (components.length == 3) ? components[2] : null;
            }

            var originalValue = this.element.getStyle(property);
            return {
                style: property.camelize(),
                originalValue: unit == 'color' ? parseColor(originalValue) : parseFloat(originalValue || 0),
                targetValue: unit == 'color' ? parseColor(value) : value,
                unit: unit
            };
        } .bind(this)).reject(function(transform) {
            return (
        (transform.originalValue == transform.targetValue) ||
        (
          transform.unit != 'color' &&
          (isNaN(transform.originalValue) || isNaN(transform.targetValue))
        )
      )
        });
    },
    update: function(position) {
        var style = {}, transform, i = this.transforms.length;
        while (i--)
            style[(transform = this.transforms[i]).style] =
        transform.unit == 'color' ? '#' +
          (Math.round(transform.originalValue[0] +
            (transform.targetValue[0] - transform.originalValue[0]) * position)).toColorPart() +
          (Math.round(transform.originalValue[1] +
            (transform.targetValue[1] - transform.originalValue[1]) * position)).toColorPart() +
          (Math.round(transform.originalValue[2] +
            (transform.targetValue[2] - transform.originalValue[2]) * position)).toColorPart() :
        (transform.originalValue +
          (transform.targetValue - transform.originalValue) * position).toFixed(3) +
            (transform.unit === null ? '' : transform.unit);
        this.element.setStyle(style, true);
    }
});

Effect.Transform = Class.create({
    initialize: function(tracks) {
        this.tracks = [];
        this.options = arguments[1] || {};
        this.addTracks(tracks);
    },
    addTracks: function(tracks) {
        tracks.each(function(track) {
            track = $H(track);
            var data = track.values().first();
            this.tracks.push($H({
                ids: track.keys().first(),
                effect: Effect.Morph,
                options: { style: data }
            }));
        } .bind(this));
        return this;
    },
    play: function() {
        return new Effect.Parallel(
      this.tracks.map(function(track) {
          var ids = track.get('ids'), effect = track.get('effect'), options = track.get('options');
          var elements = [$(ids) || $$(ids)].flatten();
          return elements.map(function(e) { return new effect(e, Object.extend({ sync: true }, options)) });
      }).flatten(),
      this.options
    );
    }
});

Element.CSS_PROPERTIES = $w(
  'backgroundColor backgroundPosition borderBottomColor borderBottomStyle ' +
  'borderBottomWidth borderLeftColor borderLeftStyle borderLeftWidth ' +
  'borderRightColor borderRightStyle borderRightWidth borderSpacing ' +
  'borderTopColor borderTopStyle borderTopWidth bottom clip color ' +
  'fontSize fontWeight height left letterSpacing lineHeight ' +
  'marginBottom marginLeft marginRight marginTop markerOffset maxHeight ' +
  'maxWidth minHeight minWidth opacity outlineColor outlineOffset ' +
  'outlineWidth paddingBottom paddingLeft paddingRight paddingTop ' +
  'right textIndent top width wordSpacing zIndex');

Element.CSS_LENGTH = /^(([\+\-]?[0-9\.]+)(em|ex|px|in|cm|mm|pt|pc|\%))|0$/;

String.__parseStyleElement = document.createElement('div');
String.prototype.parseStyle = function() {
    var style, styleRules = $H();
    if (Prototype.Browser.WebKit)
        style = new Element('div', { style: this }).style;
    else {
        String.__parseStyleElement.innerHTML = '<div style="' + this + '"></div>';
        style = String.__parseStyleElement.childNodes[0].style;
    }

    Element.CSS_PROPERTIES.each(function(property) {
        if (style[property]) styleRules.set(property, style[property]);
    });

    if (Prototype.Browser.IE && this.include('opacity'))
        styleRules.set('opacity', this.match(/opacity:\s*((?:0|1)?(?:\.\d*)?)/)[1]);

    return styleRules;
};

if (document.defaultView && document.defaultView.getComputedStyle) {
    Element.getStyles = function(element) {
        var css = document.defaultView.getComputedStyle($(element), null);
        return Element.CSS_PROPERTIES.inject({}, function(styles, property) {
            styles[property] = css[property];
            return styles;
        });
    };
} else {
    Element.getStyles = function(element) {
        element = $(element);
        var css = element.currentStyle, styles;
        styles = Element.CSS_PROPERTIES.inject({}, function(results, property) {
            results[property] = css[property];
            return results;
        });
        if (!styles.opacity) styles.opacity = element.getOpacity();
        return styles;
    };
};

Effect.Methods = {
    morph: function(element, style) {
        element = $(element);
        new Effect.Morph(element, Object.extend({ style: style }, arguments[2] || {}));
        return element;
    },
    visualEffect: function(element, effect, options) {
        element = $(element)
        var s = effect.dasherize().camelize(), klass = s.charAt(0).toUpperCase() + s.substring(1);
        new Effect[klass](element, options);
        return element;
    },
    highlight: function(element, options) {
        element = $(element);
        new Effect.Highlight(element, options);
        return element;
    }
};

$w('fade appear grow shrink fold blindUp blindDown slideUp slideDown ' +
  'pulsate shake puff squish switchOff dropOut').each(
  function(effect) {
      Effect.Methods[effect] = function(element, options) {
          element = $(element);
          Effect[effect.charAt(0).toUpperCase() + effect.substring(1)](element, options);
          return element;
      }
  }
);

$w('getInlineOpacity forceRerendering setContentZoom collectTextNodes collectTextNodesIgnoreClass getStyles').each(
  function(f) { Effect.Methods[f] = Element[f]; }
);

Element.addMethods(Effect.Methods);
if (typeof Effect == 'undefined')
    throw ("dragdrop.js requires including script.aculo.us' effects.js library");

var Droppables = {
    drops: [],

    remove: function(element) {
        this.drops = this.drops.reject(function(d) { return d.element == $(element) });
    },

    add: function(element) {
        element = $(element);
        var options = Object.extend({
            greedy: true,
            hoverclass: null,
            tree: false
        }, arguments[1] || {});

        // cache containers
        if (options.containment) {
            options._containers = [];
            var containment = options.containment;
            if ((typeof containment == 'object') &&
        (containment.constructor == Array)) {
                containment.each(function(c) { options._containers.push($(c)) });
            } else {
                options._containers.push($(containment));
            }
        }

        if (options.accept) options.accept = [options.accept].flatten();

        Element.makePositioned(element); // fix IE
        options.element = element;

        this.drops.push(options);
    },

    findDeepestChild: function(drops) {
        deepest = drops[0];

        for (i = 1; i < drops.length; ++i)
            if (Element.isParent(drops[i].element, deepest.element))
            deepest = drops[i];

        return deepest;
    },

    isContained: function(element, drop) {
        var containmentNode;
        if (drop.tree) {
            containmentNode = element.treeNode;
        } else {
            containmentNode = element.parentNode;
        }
        return drop._containers.detect(function(c) { return containmentNode == c });
    },

    isAffected: function(point, element, drop) {
        return (
      (drop.element != element) &&
      ((!drop._containers) ||
        this.isContained(element, drop)) &&
      ((!drop.accept) ||
        (Element.classNames(element).detect(
          function(v) { return drop.accept.include(v) }))) &&
      Position.within(drop.element, point[0], point[1]));
    },

    deactivate: function(drop) {
        if (drop.hoverclass)
            Element.removeClassName(drop.element, drop.hoverclass);
        this.last_active = null;
    },

    activate: function(drop) {
        if (drop.hoverclass)
            Element.addClassName(drop.element, drop.hoverclass);
        this.last_active = drop;
    },

    show: function(point, element) {
        if (!this.drops.length) return;
        var affected = [];

        if (this.last_active) this.deactivate(this.last_active);
        this.drops.each(function(drop) {
            if (Droppables.isAffected(point, element, drop))
                affected.push(drop);
        });

        if (affected.length > 0) {
            drop = Droppables.findDeepestChild(affected);
            Position.within(drop.element, point[0], point[1]);
            if (drop.onHover)
                drop.onHover(element, drop.element, Position.overlap(drop.overlap, drop.element));

            Droppables.activate(drop);
        }
    },

    fire: function(event, element) {
        if (!this.last_active) return;
        Position.prepare();

        if (this.isAffected([Event.pointerX(event), Event.pointerY(event)], element, this.last_active))
            if (this.last_active.onDrop)
            this.last_active.onDrop(element, this.last_active.element, event);
    },

    reset: function() {
        if (this.last_active)
            this.deactivate(this.last_active);
    }
}

var Draggables = {
    drags: [],
    observers: [],

    register: function(draggable) {
        if (this.drags.length == 0) {
            this.eventMouseUp = this.endDrag.bindAsEventListener(this);
            this.eventMouseMove = this.updateDrag.bindAsEventListener(this);
            this.eventKeypress = this.keyPress.bindAsEventListener(this);

            Event.observe(document, "mouseup", this.eventMouseUp);
            Event.observe(document, "mousemove", this.eventMouseMove);
            Event.observe(document, "keypress", this.eventKeypress);
        }
        this.drags.push(draggable);
    },

    unregister: function(draggable) {
        this.drags = this.drags.reject(function(d) { return d == draggable });
        if (this.drags.length == 0) {
            Event.stopObserving(document, "mouseup", this.eventMouseUp);
            Event.stopObserving(document, "mousemove", this.eventMouseMove);
            Event.stopObserving(document, "keypress", this.eventKeypress);
        }
    },

    activate: function(draggable) {
        if (draggable.options.delay) {
            this._timeout = setTimeout(function() {
                Draggables._timeout = null;
                window.focus();
                Draggables.activeDraggable = draggable;
            } .bind(this), draggable.options.delay);
        } else {
            window.focus(); // allows keypress events if window isn't currently focused, fails for Safari
            this.activeDraggable = draggable;
        }
    },

    deactivate: function() {
        this.activeDraggable = null;
    },

    updateDrag: function(event) {
        if (!this.activeDraggable) return;
        var pointer = [Event.pointerX(event), Event.pointerY(event)];
        // Mozilla-based browsers fire successive mousemove events with
        // the same coordinates, prevent needless redrawing (moz bug?)
        if (this._lastPointer && (this._lastPointer.inspect() == pointer.inspect())) return;
        this._lastPointer = pointer;

        this.activeDraggable.updateDrag(event, pointer);
    },

    endDrag: function(event) {
        if (this._timeout) {
            clearTimeout(this._timeout);
            this._timeout = null;
        }
        if (!this.activeDraggable) return;
        this._lastPointer = null;
        this.activeDraggable.endDrag(event);
        this.activeDraggable = null;
    },

    keyPress: function(event) {
        if (this.activeDraggable)
            this.activeDraggable.keyPress(event);
    },

    addObserver: function(observer) {
        this.observers.push(observer);
        this._cacheObserverCallbacks();
    },

    removeObserver: function(element) {  // element instead of observer fixes mem leaks
        this.observers = this.observers.reject(function(o) { return o.element == element });
        this._cacheObserverCallbacks();
    },

    notify: function(eventName, draggable, event) {  // 'onStart', 'onEnd', 'onDrag'
        if (this[eventName + 'Count'] > 0)
            this.observers.each(function(o) {
                if (o[eventName]) o[eventName](eventName, draggable, event);
            });
        if (draggable.options[eventName]) draggable.options[eventName](draggable, event);
    },

    _cacheObserverCallbacks: function() {
        ['onStart', 'onEnd', 'onDrag'].each(function(eventName) {
            Draggables[eventName + 'Count'] = Draggables.observers.select(
        function(o) { return o[eventName]; }
      ).length;
        });
    }
}

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

var Draggable = Class.create();
Draggable._dragging = {};

Draggable.prototype = {
    initialize: function(element) {
        var defaults = {
            handle: false,
            reverteffect: function(element, top_offset, left_offset) {
                var dur = Math.sqrt(Math.abs(top_offset ^ 2) + Math.abs(left_offset ^ 2)) * 0.02;
                new Effect.Move(element, { x: -left_offset, y: -top_offset, duration: dur,
                    queue: { scope: '_draggable', position: 'end' }
                });
            },
            endeffect: function(element) {
                var toOpacity = typeof element._opacity == 'number' ? element._opacity : 1.0;
                new Effect.Opacity(element, { duration: 0.2, from: 0.7, to: toOpacity,
                    queue: { scope: '_draggable', position: 'end' },
                    afterFinish: function() {
                        Draggable._dragging[element] = false
                    }
                });
            },
            zindex: 1000,
            revert: false,
            scroll: false,
            scrollSensitivity: 20,
            scrollSpeed: 15,
            snap: false,  // false, or xy or [x,y] or function(x,y){ return [x,y] }
            delay: 0
        };

        if (!arguments[1] || typeof arguments[1].endeffect == 'undefined')
            Object.extend(defaults, {
                starteffect: function(element) {
                    element._opacity = Element.getOpacity(element);
                    Draggable._dragging[element] = true;
                    new Effect.Opacity(element, { duration: 0.2, from: element._opacity, to: 0.7 });
                }
            });

        var options = Object.extend(defaults, arguments[1] || {});

        this.element = $(element);

        if (options.handle && (typeof options.handle == 'string'))
            this.handle = this.element.down('.' + options.handle, 0);

        if (!this.handle) this.handle = $(options.handle);
        if (!this.handle) this.handle = this.element;

        if (options.scroll && !options.scroll.scrollTo && !options.scroll.outerHTML) {
            options.scroll = $(options.scroll);
            this._isScrollChild = Element.childOf(this.element, options.scroll);
        }

        Element.makePositioned(this.element); // fix IE    

        this.delta = this.currentDelta();
        this.options = options;
        this.dragging = false;

        this.eventMouseDown = this.initDrag.bindAsEventListener(this);
        Event.observe(this.handle, "mousedown", this.eventMouseDown);

        Draggables.register(this);
    },

    destroy: function() {
        Event.stopObserving(this.handle, "mousedown", this.eventMouseDown);
        Draggables.unregister(this);
    },

    currentDelta: function() {
        return ([
      parseInt(Element.getStyle(this.element, 'left') || '0'),
      parseInt(Element.getStyle(this.element, 'top') || '0')]);
    },

    initDrag: function(event) {
        if (typeof Draggable._dragging[this.element] != 'undefined' &&
      Draggable._dragging[this.element]) return;
        if (Event.isLeftClick(event)) {
            // abort on form elements, fixes a Firefox issue
            var src = Event.element(event);
            if ((tag_name = src.tagName.toUpperCase()) && (
        tag_name == 'INPUT' ||
        tag_name == 'SELECT' ||
        tag_name == 'OPTION' ||
        tag_name == 'BUTTON' ||
        tag_name == 'TEXTAREA')) return;

            var pointer = [Event.pointerX(event), Event.pointerY(event)];
            var pos = Position.cumulativeOffset(this.element);
            this.offset = [0, 1].map(function(i) { return (pointer[i] - pos[i]) });

            Draggables.activate(this);
            Event.stop(event);
        }
    },

    startDrag: function(event) {
        this.dragging = true;

        if (this.options.zindex) {
            this.originalZ = parseInt(Element.getStyle(this.element, 'z-index') || 0);
            this.element.style.zIndex = this.options.zindex;
        }

        if (this.options.ghosting) {
            this._clone = this.element.cloneNode(true);
            Position.absolutize(this.element);
            this.element.parentNode.insertBefore(this._clone, this.element);
        }

        if (this.options.scroll) {
            if (this.options.scroll == window) {
                var where = this._getWindowScroll(this.options.scroll);
                this.originalScrollLeft = where.left;
                this.originalScrollTop = where.top;
            } else {
                this.originalScrollLeft = this.options.scroll.scrollLeft;
                this.originalScrollTop = this.options.scroll.scrollTop;
            }
        }

        Draggables.notify('onStart', this, event);

        if (this.options.starteffect) this.options.starteffect(this.element);
    },

    updateDrag: function(event, pointer) {
        if (!this.dragging) this.startDrag(event);
        Position.prepare();
        Droppables.show(pointer, this.element);
        Draggables.notify('onDrag', this, event);

        this.draw(pointer);
        if (this.options.change) this.options.change(this);

        if (this.options.scroll) {
            this.stopScrolling();

            var p;
            if (this.options.scroll == window) {
                with (this._getWindowScroll(this.options.scroll)) { p = [left, top, left + width, top + height]; }
            } else {
                p = Position.page(this.options.scroll);
                p[0] += this.options.scroll.scrollLeft + Position.deltaX;
                p[1] += this.options.scroll.scrollTop + Position.deltaY;
                p.push(p[0] + this.options.scroll.offsetWidth);
                p.push(p[1] + this.options.scroll.offsetHeight);
            }
            var speed = [0, 0];
            if (pointer[0] < (p[0] + this.options.scrollSensitivity)) speed[0] = pointer[0] - (p[0] + this.options.scrollSensitivity);
            if (pointer[1] < (p[1] + this.options.scrollSensitivity)) speed[1] = pointer[1] - (p[1] + this.options.scrollSensitivity);
            if (pointer[0] > (p[2] - this.options.scrollSensitivity)) speed[0] = pointer[0] - (p[2] - this.options.scrollSensitivity);
            if (pointer[1] > (p[3] - this.options.scrollSensitivity)) speed[1] = pointer[1] - (p[3] - this.options.scrollSensitivity);
            this.startScrolling(speed);
        }

        // fix AppleWebKit rendering
        if (navigator.appVersion.indexOf('AppleWebKit') > 0) window.scrollBy(0, 0);

        Event.stop(event);
    },

    finishDrag: function(event, success) {
        this.dragging = false;

        if (this.options.ghosting) {
            Position.relativize(this.element);
            Element.remove(this._clone);
            this._clone = null;
        }

        if (success) Droppables.fire(event, this.element);
        Draggables.notify('onEnd', this, event);

        var revert = this.options.revert;
        if (revert && typeof revert == 'function') revert = revert(this.element);

        var d = this.currentDelta();
        if (revert && this.options.reverteffect) {
            this.options.reverteffect(this.element,
        d[1] - this.delta[1], d[0] - this.delta[0]);
        } else {
            this.delta = d;
        }

        if (this.options.zindex)
            this.element.style.zIndex = this.originalZ;

        if (this.options.endeffect)
            this.options.endeffect(this.element);

        Draggables.deactivate(this);
        Droppables.reset();
    },

    keyPress: function(event) {
        if (event.keyCode != Event.KEY_ESC) return;
        this.finishDrag(event, false);
        Event.stop(event);
    },

    endDrag: function(event) {
        if (!this.dragging) return;
        this.stopScrolling();
        this.finishDrag(event, true);
        Event.stop(event);
    },

    draw: function(point) {
        var pos = Position.cumulativeOffset(this.element);
        if (this.options.ghosting) {
            var r = Position.realOffset(this.element);
            pos[0] += r[0] - Position.deltaX; pos[1] += r[1] - Position.deltaY;
        }

        var d = this.currentDelta();
        pos[0] -= d[0]; pos[1] -= d[1];

        if (this.options.scroll && (this.options.scroll != window && this._isScrollChild)) {
            pos[0] -= this.options.scroll.scrollLeft - this.originalScrollLeft;
            pos[1] -= this.options.scroll.scrollTop - this.originalScrollTop;
        }

        var p = [0, 1].map(function(i) {
            return (point[i] - pos[i] - this.offset[i])
        } .bind(this));

        if (this.options.snap) {
            if (typeof this.options.snap == 'function') {
                p = this.options.snap(p[0], p[1], this);
            } else {
                if (this.options.snap instanceof Array) {
                    p = p.map(function(v, i) {
                        return Math.round(v / this.options.snap[i]) * this.options.snap[i]
                    } .bind(this))
                } else {
                    p = p.map(function(v) {
                        return Math.round(v / this.options.snap) * this.options.snap
                    } .bind(this))
                }
            } 
        }

        var style = this.element.style;
        if ((!this.options.constraint) || (this.options.constraint == 'horizontal'))
            style.left = p[0] + "px";
        if ((!this.options.constraint) || (this.options.constraint == 'vertical'))
            style.top = p[1] + "px";

        if (style.visibility == "hidden") style.visibility = ""; // fix gecko rendering
    },

    stopScrolling: function() {
        if (this.scrollInterval) {
            clearInterval(this.scrollInterval);
            this.scrollInterval = null;
            Draggables._lastScrollPointer = null;
        }
    },

    startScrolling: function(speed) {
        if (!(speed[0] || speed[1])) return;
        this.scrollSpeed = [speed[0] * this.options.scrollSpeed, speed[1] * this.options.scrollSpeed];
        this.lastScrolled = new Date();
        this.scrollInterval = setInterval(this.scroll.bind(this), 10);
    },

    scroll: function() {
        var current = new Date();
        var delta = current - this.lastScrolled;
        this.lastScrolled = current;
        if (this.options.scroll == window) {
            with (this._getWindowScroll(this.options.scroll)) {
                if (this.scrollSpeed[0] || this.scrollSpeed[1]) {
                    var d = delta / 1000;
                    this.options.scroll.scrollTo(left + d * this.scrollSpeed[0], top + d * this.scrollSpeed[1]);
                }
            }
        } else {
            this.options.scroll.scrollLeft += this.scrollSpeed[0] * delta / 1000;
            this.options.scroll.scrollTop += this.scrollSpeed[1] * delta / 1000;
        }

        Position.prepare();
        Droppables.show(Draggables._lastPointer, this.element);
        Draggables.notify('onDrag', this);
        if (this._isScrollChild) {
            Draggables._lastScrollPointer = Draggables._lastScrollPointer || $A(Draggables._lastPointer);
            Draggables._lastScrollPointer[0] += this.scrollSpeed[0] * delta / 1000;
            Draggables._lastScrollPointer[1] += this.scrollSpeed[1] * delta / 1000;
            if (Draggables._lastScrollPointer[0] < 0)
                Draggables._lastScrollPointer[0] = 0;
            if (Draggables._lastScrollPointer[1] < 0)
                Draggables._lastScrollPointer[1] = 0;
            this.draw(Draggables._lastScrollPointer);
        }

        if (this.options.change) this.options.change(this);
    },

    _getWindowScroll: function(w) {
        var T, L, W, H;
        with (w.document) {
            if (w.document.documentElement && documentElement.scrollTop) {
                T = documentElement.scrollTop;
                L = documentElement.scrollLeft;
            } else if (w.document.body) {
                T = body.scrollTop;
                L = body.scrollLeft;
            }
            if (w.innerWidth) {
                W = w.innerWidth;
                H = w.innerHeight;
            } else if (w.document.documentElement && documentElement.clientWidth) {
                W = documentElement.clientWidth;
                H = documentElement.clientHeight;
            } else {
                W = body.offsetWidth;
                H = body.offsetHeight
            }
        }
        return { top: T, left: L, width: W, height: H };
    }
}

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

var SortableObserver = Class.create();
SortableObserver.prototype = {
    initialize: function(element, observer) {
        this.element = $(element);
        this.observer = observer;
        this.lastValue = Sortable.serialize(this.element);
    },

    onStart: function() {
        this.lastValue = Sortable.serialize(this.element);
    },

    onEnd: function() {
        Sortable.unmark();
        if (this.lastValue != Sortable.serialize(this.element))
            this.observer(this.element)
    }
}

var Sortable = {
    SERIALIZE_RULE: /^[^_\-](?:[A-Za-z0-9\-\_]*)[_](.*)$/,

    sortables: {},

    _findRootElement: function(element) {
        while (element.tagName.toUpperCase() != "BODY") {
            if (element.id && Sortable.sortables[element.id]) return element;
            element = element.parentNode;
        }
    },

    options: function(element) {
        element = Sortable._findRootElement($(element));
        if (!element) return;
        return Sortable.sortables[element.id];
    },

    destroy: function(element) {
        var s = Sortable.options(element);

        if (s) {
            Draggables.removeObserver(s.element);
            s.droppables.each(function(d) { Droppables.remove(d) });
            s.draggables.invoke('destroy');

            delete Sortable.sortables[s.element.id];
        }
    },

    create: function(element) {
        element = $(element);
        var options = Object.extend({
            element: element,
            tag: 'li',       // assumes li children, override with tag: 'tagname'
            dropOnEmpty: false,
            tree: false,
            treeTag: 'ul',
            overlap: 'vertical', // one of 'vertical', 'horizontal'
            constraint: 'vertical', // one of 'vertical', 'horizontal', false
            containment: element,    // also takes array of elements (or id's); or false
            handle: false,      // or a CSS class
            only: false,
            delay: 0,
            hoverclass: null,
            ghosting: false,
            scroll: false,
            scrollSensitivity: 20,
            scrollSpeed: 15,
            format: this.SERIALIZE_RULE,
            onChange: Prototype.emptyFunction,
            onUpdate: Prototype.emptyFunction
        }, arguments[1] || {});

        // clear any old sortable with same element
        this.destroy(element);

        // build options for the draggables
        var options_for_draggable = {
            revert: true,
            scroll: options.scroll,
            scrollSpeed: options.scrollSpeed,
            scrollSensitivity: options.scrollSensitivity,
            delay: options.delay,
            ghosting: options.ghosting,
            constraint: options.constraint,
            handle: options.handle
        };

        if (options.starteffect)
            options_for_draggable.starteffect = options.starteffect;

        if (options.reverteffect)
            options_for_draggable.reverteffect = options.reverteffect;
        else
            if (options.ghosting) options_for_draggable.reverteffect = function(element) {
                element.style.top = 0;
                element.style.left = 0;
            };

        if (options.endeffect)
            options_for_draggable.endeffect = options.endeffect;

        if (options.zindex)
            options_for_draggable.zindex = options.zindex;

        // build options for the droppables  
        var options_for_droppable = {
            overlap: options.overlap,
            containment: options.containment,
            tree: options.tree,
            hoverclass: options.hoverclass,
            onHover: Sortable.onHover
        }

        var options_for_tree = {
            onHover: Sortable.onEmptyHover,
            overlap: options.overlap,
            containment: options.containment,
            hoverclass: options.hoverclass
        }

        // fix for gecko engine
        Element.cleanWhitespace(element);

        options.draggables = [];
        options.droppables = [];

        // drop on empty handling
        if (options.dropOnEmpty || options.tree) {
            Droppables.add(element, options_for_tree);
            options.droppables.push(element);
        }

        (this.findElements(element, options) || []).each(function(e) {
            // handles are per-draggable
            var handle = options.handle ?
        $(e).down('.' + options.handle, 0) : e;
            options.draggables.push(
        new Draggable(e, Object.extend(options_for_draggable, { handle: handle })));
            Droppables.add(e, options_for_droppable);
            if (options.tree) e.treeNode = element;
            options.droppables.push(e);
        });

        if (options.tree) {
            (Sortable.findTreeElements(element, options) || []).each(function(e) {
                Droppables.add(e, options_for_tree);
                e.treeNode = element;
                options.droppables.push(e);
            });
        }

        // keep reference
        this.sortables[element.id] = options;

        // for onupdate
        Draggables.addObserver(new SortableObserver(element, options.onUpdate));

    },

    // return all suitable-for-sortable elements in a guaranteed order
    findElements: function(element, options) {
        return Element.findChildren(
      element, options.only, options.tree ? true : false, options.tag);
    },

    findTreeElements: function(element, options) {
        return Element.findChildren(
      element, options.only, options.tree ? true : false, options.treeTag);
    },

    onHover: function(element, dropon, overlap) {
        if (Element.isParent(dropon, element)) return;

        if (overlap > .33 && overlap < .66 && Sortable.options(dropon).tree) {
            return;
        } else if (overlap > 0.5) {
            Sortable.mark(dropon, 'before');
            if (dropon.previousSibling != element) {
                var oldParentNode = element.parentNode;
                element.style.visibility = "hidden"; // fix gecko rendering
                dropon.parentNode.insertBefore(element, dropon);
                if (dropon.parentNode != oldParentNode)
                    Sortable.options(oldParentNode).onChange(element);
                Sortable.options(dropon.parentNode).onChange(element);
            }
        } else {
            Sortable.mark(dropon, 'after');
            var nextElement = dropon.nextSibling || null;
            if (nextElement != element) {
                var oldParentNode = element.parentNode;
                element.style.visibility = "hidden"; // fix gecko rendering
                dropon.parentNode.insertBefore(element, nextElement);
                if (dropon.parentNode != oldParentNode)
                    Sortable.options(oldParentNode).onChange(element);
                Sortable.options(dropon.parentNode).onChange(element);
            }
        }
    },

    onEmptyHover: function(element, dropon, overlap) {
        var oldParentNode = element.parentNode;
        var droponOptions = Sortable.options(dropon);

        if (!Element.isParent(dropon, element)) {
            var index;

            var children = Sortable.findElements(dropon, { tag: droponOptions.tag, only: droponOptions.only });
            var child = null;

            if (children) {
                var offset = Element.offsetSize(dropon, droponOptions.overlap) * (1.0 - overlap);

                for (index = 0; index < children.length; index += 1) {
                    if (offset - Element.offsetSize(children[index], droponOptions.overlap) >= 0) {
                        offset -= Element.offsetSize(children[index], droponOptions.overlap);
                    } else if (offset - (Element.offsetSize(children[index], droponOptions.overlap) / 2) >= 0) {
                        child = index + 1 < children.length ? children[index + 1] : null;
                        break;
                    } else {
                        child = children[index];
                        break;
                    }
                }
            }

            dropon.insertBefore(element, child);

            Sortable.options(oldParentNode).onChange(element);
            droponOptions.onChange(element);
        }
    },

    unmark: function() {
        if (Sortable._marker) Sortable._marker.hide();
    },

    mark: function(dropon, position) {
        // mark on ghosting only
        var sortable = Sortable.options(dropon.parentNode);
        if (sortable && !sortable.ghosting) return;

        if (!Sortable._marker) {
            Sortable._marker =
        ($('dropmarker') || Element.extend(document.createElement('DIV'))).
          hide().addClassName('dropmarker').setStyle({ position: 'absolute' });
            document.getElementsByTagName("body").item(0).appendChild(Sortable._marker);
        }
        var offsets = Position.cumulativeOffset(dropon);
        Sortable._marker.setStyle({ left: offsets[0] + 'px', top: offsets[1] + 'px' });

        if (position == 'after')
            if (sortable.overlap == 'horizontal')
            Sortable._marker.setStyle({ left: (offsets[0] + dropon.clientWidth) + 'px' });
        else
            Sortable._marker.setStyle({ top: (offsets[1] + dropon.clientHeight) + 'px' });

        Sortable._marker.show();
    },

    _tree: function(element, options, parent) {
        var children = Sortable.findElements(element, options) || [];

        for (var i = 0; i < children.length; ++i) {
            var match = children[i].id.match(options.format);

            if (!match) continue;

            var child = {
                id: encodeURIComponent(match ? match[1] : null),
                element: element,
                parent: parent,
                children: [],
                position: parent.children.length,
                container: $(children[i]).down(options.treeTag)
            }

            /* Get the element containing the children and recurse over it */
            if (child.container)
                this._tree(child.container, options, child)

            parent.children.push(child);
        }

        return parent;
    },

    tree: function(element) {
        element = $(element);
        var sortableOptions = this.options(element);
        var options = Object.extend({
            tag: sortableOptions.tag,
            treeTag: sortableOptions.treeTag,
            only: sortableOptions.only,
            name: element.id,
            format: sortableOptions.format
        }, arguments[1] || {});

        var root = {
            id: null,
            parent: null,
            children: [],
            container: element,
            position: 0
        }

        return Sortable._tree(element, options, root);
    },

    /* Construct a [i] index for a particular node */
    _constructIndex: function(node) {
        var index = '';
        do {
            if (node.id) index = '[' + node.position + ']' + index;
        } while ((node = node.parent) != null);
        return index;
    },

    sequence: function(element) {
        element = $(element);
        var options = Object.extend(this.options(element), arguments[1] || {});

        return $(this.findElements(element, options) || []).map(function(item) {
            return item.id.match(options.format) ? item.id.match(options.format)[1] : '';
        });
    },

    setSequence: function(element, new_sequence) {
        element = $(element);
        var options = Object.extend(this.options(element), arguments[2] || {});

        var nodeMap = {};
        this.findElements(element, options).each(function(n) {
            if (n.id.match(options.format))
                nodeMap[n.id.match(options.format)[1]] = [n, n.parentNode];
            n.parentNode.removeChild(n);
        });

        new_sequence.each(function(ident) {
            var n = nodeMap[ident];
            if (n) {
                n[1].appendChild(n[0]);
                delete nodeMap[ident];
            }
        });
    },

    serialize: function(element) {
        element = $(element);
        var options = Object.extend(Sortable.options(element), arguments[1] || {});
        var name = encodeURIComponent(
      (arguments[1] && arguments[1].name) ? arguments[1].name : element.id);

        if (options.tree) {
            return Sortable.tree(element, arguments[1]).children.map(function(item) {
                return [name + Sortable._constructIndex(item) + "[id]=" +
                encodeURIComponent(item.id)].concat(item.children.map(arguments.callee));
            }).flatten().join('&');
        } else {
            return Sortable.sequence(element, arguments[1]).map(function(item) {
                return name + "[]=" + encodeURIComponent(item);
            }).join('&');
        }
    }
};

// Returns true if child is contained within element
Element.isParent = function(child, element) {
    if (!child.parentNode || child == element) return false;
    if (child.parentNode == element) return true;
    return Element.isParent(child.parentNode, element);
};

Element.findChildren = function(element, only, recursive, tagName) {
    if (!element.hasChildNodes()) return null;
    tagName = tagName.toUpperCase();
    if (only) only = [only].flatten();
    var elements = [];
    $A(element.childNodes).each(function(e) {
        if (e.tagName && e.tagName.toUpperCase() == tagName &&
      (!only || (Element.classNames(e).detect(function(v) { return only.include(v) }))))
            elements.push(e);
        if (recursive) {
            var grandchildren = Element.findChildren(e, only, recursive, tagName);
            if (grandchildren) elements.push(grandchildren);
        }
    });

    return (elements.length > 0 ? elements.flatten() : []);
};

Element.offsetSize = function(element, type) {
    return element['offset' + ((type == 'vertical' || type == 'height') ? 'Height' : 'Width')];
};