terom@27: // script.aculo.us dragdrop.js v1.8.0, Tue Nov 06 15:01:40 +0300 2007
terom@27: 
terom@27: // Copyright (c) 2005-2007 Thomas Fuchs (http://script.aculo.us, http://mir.aculo.us)
terom@27: //           (c) 2005-2007 Sammi Williams (http://www.oriontransfer.co.nz, sammi@oriontransfer.co.nz)
terom@27: // 
terom@27: // script.aculo.us is freely distributable under the terms of an MIT-style license.
terom@27: // For details, see the script.aculo.us web site: http://script.aculo.us/
terom@27: 
terom@27: if(Object.isUndefined(Effect))
terom@27:   throw("dragdrop.js requires including script.aculo.us' effects.js library");
terom@27: 
terom@27: var Droppables = {
terom@27:   drops: [],
terom@27: 
terom@27:   remove: function(element) {
terom@27:     this.drops = this.drops.reject(function(d) { return d.element==$(element) });
terom@27:   },
terom@27: 
terom@27:   add: function(element) {
terom@27:     element = $(element);
terom@27:     var options = Object.extend({
terom@27:       greedy:     true,
terom@27:       hoverclass: null,
terom@27:       tree:       false
terom@27:     }, arguments[1] || { });
terom@27: 
terom@27:     // cache containers
terom@27:     if(options.containment) {
terom@27:       options._containers = [];
terom@27:       var containment = options.containment;
terom@27:       if(Object.isArray(containment)) {
terom@27:         containment.each( function(c) { options._containers.push($(c)) });
terom@27:       } else {
terom@27:         options._containers.push($(containment));
terom@27:       }
terom@27:     }
terom@27:     
terom@27:     if(options.accept) options.accept = [options.accept].flatten();
terom@27: 
terom@27:     Element.makePositioned(element); // fix IE
terom@27:     options.element = element;
terom@27: 
terom@27:     this.drops.push(options);
terom@27:   },
terom@27:   
terom@27:   findDeepestChild: function(drops) {
terom@27:     deepest = drops[0];
terom@27:       
terom@27:     for (i = 1; i < drops.length; ++i)
terom@27:       if (Element.isParent(drops[i].element, deepest.element))
terom@27:         deepest = drops[i];
terom@27:     
terom@27:     return deepest;
terom@27:   },
terom@27: 
terom@27:   isContained: function(element, drop) {
terom@27:     var containmentNode;
terom@27:     if(drop.tree) {
terom@27:       containmentNode = element.treeNode; 
terom@27:     } else {
terom@27:       containmentNode = element.parentNode;
terom@27:     }
terom@27:     return drop._containers.detect(function(c) { return containmentNode == c });
terom@27:   },
terom@27:   
terom@27:   isAffected: function(point, element, drop) {
terom@27:     return (
terom@27:       (drop.element!=element) &&
terom@27:       ((!drop._containers) ||
terom@27:         this.isContained(element, drop)) &&
terom@27:       ((!drop.accept) ||
terom@27:         (Element.classNames(element).detect( 
terom@27:           function(v) { return drop.accept.include(v) } ) )) &&
terom@27:       Position.within(drop.element, point[0], point[1]) );
terom@27:   },
terom@27: 
terom@27:   deactivate: function(drop) {
terom@27:     if(drop.hoverclass)
terom@27:       Element.removeClassName(drop.element, drop.hoverclass);
terom@27:     this.last_active = null;
terom@27:   },
terom@27: 
terom@27:   activate: function(drop) {
terom@27:     if(drop.hoverclass)
terom@27:       Element.addClassName(drop.element, drop.hoverclass);
terom@27:     this.last_active = drop;
terom@27:   },
terom@27: 
terom@27:   show: function(point, element) {
terom@27:     if(!this.drops.length) return;
terom@27:     var drop, affected = [];
terom@27:     
terom@27:     this.drops.each( function(drop) {
terom@27:       if(Droppables.isAffected(point, element, drop))
terom@27:         affected.push(drop);
terom@27:     });
terom@27:         
terom@27:     if(affected.length>0)
terom@27:       drop = Droppables.findDeepestChild(affected);
terom@27: 
terom@27:     if(this.last_active && this.last_active != drop) this.deactivate(this.last_active);
terom@27:     if (drop) {
terom@27:       Position.within(drop.element, point[0], point[1]);
terom@27:       if(drop.onHover)
terom@27:         drop.onHover(element, drop.element, Position.overlap(drop.overlap, drop.element));
terom@27:       
terom@27:       if (drop != this.last_active) Droppables.activate(drop);
terom@27:     }
terom@27:   },
terom@27: 
terom@27:   fire: function(event, element) {
terom@27:     if(!this.last_active) return;
terom@27:     Position.prepare();
terom@27: 
terom@27:     if (this.isAffected([Event.pointerX(event), Event.pointerY(event)], element, this.last_active))
terom@27:       if (this.last_active.onDrop) {
terom@27:         this.last_active.onDrop(element, this.last_active.element, event); 
terom@27:         return true; 
terom@27:       }
terom@27:   },
terom@27: 
terom@27:   reset: function() {
terom@27:     if(this.last_active)
terom@27:       this.deactivate(this.last_active);
terom@27:   }
terom@27: }
terom@27: 
terom@27: var Draggables = {
terom@27:   drags: [],
terom@27:   observers: [],
terom@27:   
terom@27:   register: function(draggable) {
terom@27:     if(this.drags.length == 0) {
terom@27:       this.eventMouseUp   = this.endDrag.bindAsEventListener(this);
terom@27:       this.eventMouseMove = this.updateDrag.bindAsEventListener(this);
terom@27:       this.eventKeypress  = this.keyPress.bindAsEventListener(this);
terom@27:       
terom@27:       Event.observe(document, "mouseup", this.eventMouseUp);
terom@27:       Event.observe(document, "mousemove", this.eventMouseMove);
terom@27:       Event.observe(document, "keypress", this.eventKeypress);
terom@27:     }
terom@27:     this.drags.push(draggable);
terom@27:   },
terom@27:   
terom@27:   unregister: function(draggable) {
terom@27:     this.drags = this.drags.reject(function(d) { return d==draggable });
terom@27:     if(this.drags.length == 0) {
terom@27:       Event.stopObserving(document, "mouseup", this.eventMouseUp);
terom@27:       Event.stopObserving(document, "mousemove", this.eventMouseMove);
terom@27:       Event.stopObserving(document, "keypress", this.eventKeypress);
terom@27:     }
terom@27:   },
terom@27:   
terom@27:   activate: function(draggable) {
terom@27:     if(draggable.options.delay) { 
terom@27:       this._timeout = setTimeout(function() { 
terom@27:         Draggables._timeout = null; 
terom@27:         window.focus(); 
terom@27:         Draggables.activeDraggable = draggable; 
terom@27:       }.bind(this), draggable.options.delay); 
terom@27:     } else {
terom@27:       window.focus(); // allows keypress events if window isn't currently focused, fails for Safari
terom@27:       this.activeDraggable = draggable;
terom@27:     }
terom@27:   },
terom@27:   
terom@27:   deactivate: function() {
terom@27:     this.activeDraggable = null;
terom@27:   },
terom@27:   
terom@27:   updateDrag: function(event) {
terom@27:     if(!this.activeDraggable) return;
terom@27:     var pointer = [Event.pointerX(event), Event.pointerY(event)];
terom@27:     // Mozilla-based browsers fire successive mousemove events with
terom@27:     // the same coordinates, prevent needless redrawing (moz bug?)
terom@27:     if(this._lastPointer && (this._lastPointer.inspect() == pointer.inspect())) return;
terom@27:     this._lastPointer = pointer;
terom@27:     
terom@27:     this.activeDraggable.updateDrag(event, pointer);
terom@27:   },
terom@27:   
terom@27:   endDrag: function(event) {
terom@27:     if(this._timeout) { 
terom@27:       clearTimeout(this._timeout); 
terom@27:       this._timeout = null; 
terom@27:     }
terom@27:     if(!this.activeDraggable) return;
terom@27:     this._lastPointer = null;
terom@27:     this.activeDraggable.endDrag(event);
terom@27:     this.activeDraggable = null;
terom@27:   },
terom@27:   
terom@27:   keyPress: function(event) {
terom@27:     if(this.activeDraggable)
terom@27:       this.activeDraggable.keyPress(event);
terom@27:   },
terom@27:   
terom@27:   addObserver: function(observer) {
terom@27:     this.observers.push(observer);
terom@27:     this._cacheObserverCallbacks();
terom@27:   },
terom@27:   
terom@27:   removeObserver: function(element) {  // element instead of observer fixes mem leaks
terom@27:     this.observers = this.observers.reject( function(o) { return o.element==element });
terom@27:     this._cacheObserverCallbacks();
terom@27:   },
terom@27:   
terom@27:   notify: function(eventName, draggable, event) {  // 'onStart', 'onEnd', 'onDrag'
terom@27:     if(this[eventName+'Count'] > 0)
terom@27:       this.observers.each( function(o) {
terom@27:         if(o[eventName]) o[eventName](eventName, draggable, event);
terom@27:       });
terom@27:     if(draggable.options[eventName]) draggable.options[eventName](draggable, event);
terom@27:   },
terom@27:   
terom@27:   _cacheObserverCallbacks: function() {
terom@27:     ['onStart','onEnd','onDrag'].each( function(eventName) {
terom@27:       Draggables[eventName+'Count'] = Draggables.observers.select(
terom@27:         function(o) { return o[eventName]; }
terom@27:       ).length;
terom@27:     });
terom@27:   }
terom@27: }
terom@27: 
terom@27: /*--------------------------------------------------------------------------*/
terom@27: 
terom@27: var Draggable = Class.create({
terom@27:   initialize: function(element) {
terom@27:     var defaults = {
terom@27:       handle: false,
terom@27:       reverteffect: function(element, top_offset, left_offset) {
terom@27:         var dur = Math.sqrt(Math.abs(top_offset^2)+Math.abs(left_offset^2))*0.02;
terom@27:         new Effect.Move(element, { x: -left_offset, y: -top_offset, duration: dur,
terom@27:           queue: {scope:'_draggable', position:'end'}
terom@27:         });
terom@27:       },
terom@27:       endeffect: function(element) {
terom@27:         var toOpacity = Object.isNumber(element._opacity) ? element._opacity : 1.0;
terom@27:         new Effect.Opacity(element, {duration:0.2, from:0.7, to:toOpacity, 
terom@27:           queue: {scope:'_draggable', position:'end'},
terom@27:           afterFinish: function(){ 
terom@27:             Draggable._dragging[element] = false 
terom@27:           }
terom@27:         }); 
terom@27:       },
terom@27:       zindex: 1000,
terom@27:       revert: false,
terom@27:       quiet: false,
terom@27:       scroll: false,
terom@27:       scrollSensitivity: 20,
terom@27:       scrollSpeed: 15,
terom@27:       snap: false,  // false, or xy or [x,y] or function(x,y){ return [x,y] }
terom@27:       delay: 0
terom@27:     };
terom@27:     
terom@27:     if(!arguments[1] || Object.isUndefined(arguments[1].endeffect))
terom@27:       Object.extend(defaults, {
terom@27:         starteffect: function(element) {
terom@27:           element._opacity = Element.getOpacity(element);
terom@27:           Draggable._dragging[element] = true;
terom@27:           new Effect.Opacity(element, {duration:0.2, from:element._opacity, to:0.7}); 
terom@27:         }
terom@27:       });
terom@27:     
terom@27:     var options = Object.extend(defaults, arguments[1] || { });
terom@27: 
terom@27:     this.element = $(element);
terom@27:     
terom@27:     if(options.handle && Object.isString(options.handle))
terom@27:       this.handle = this.element.down('.'+options.handle, 0);
terom@27:     
terom@27:     if(!this.handle) this.handle = $(options.handle);
terom@27:     if(!this.handle) this.handle = this.element;
terom@27:     
terom@27:     if(options.scroll && !options.scroll.scrollTo && !options.scroll.outerHTML) {
terom@27:       options.scroll = $(options.scroll);
terom@27:       this._isScrollChild = Element.childOf(this.element, options.scroll);
terom@27:     }
terom@27: 
terom@27:     Element.makePositioned(this.element); // fix IE    
terom@27: 
terom@27:     this.options  = options;
terom@27:     this.dragging = false;   
terom@27: 
terom@27:     this.eventMouseDown = this.initDrag.bindAsEventListener(this);
terom@27:     Event.observe(this.handle, "mousedown", this.eventMouseDown);
terom@27:     
terom@27:     Draggables.register(this);
terom@27:   },
terom@27:   
terom@27:   destroy: function() {
terom@27:     Event.stopObserving(this.handle, "mousedown", this.eventMouseDown);
terom@27:     Draggables.unregister(this);
terom@27:   },
terom@27:   
terom@27:   currentDelta: function() {
terom@27:     return([
terom@27:       parseInt(Element.getStyle(this.element,'left') || '0'),
terom@27:       parseInt(Element.getStyle(this.element,'top') || '0')]);
terom@27:   },
terom@27:   
terom@27:   initDrag: function(event) {
terom@27:     if(!Object.isUndefined(Draggable._dragging[this.element]) &&
terom@27:       Draggable._dragging[this.element]) return;
terom@27:     if(Event.isLeftClick(event)) {    
terom@27:       // abort on form elements, fixes a Firefox issue
terom@27:       var src = Event.element(event);
terom@27:       if((tag_name = src.tagName.toUpperCase()) && (
terom@27:         tag_name=='INPUT' ||
terom@27:         tag_name=='SELECT' ||
terom@27:         tag_name=='OPTION' ||
terom@27:         tag_name=='BUTTON' ||
terom@27:         tag_name=='TEXTAREA')) return;
terom@27:         
terom@27:       var pointer = [Event.pointerX(event), Event.pointerY(event)];
terom@27:       var pos     = Position.cumulativeOffset(this.element);
terom@27:       this.offset = [0,1].map( function(i) { return (pointer[i] - pos[i]) });
terom@27:       
terom@27:       Draggables.activate(this);
terom@27:       Event.stop(event);
terom@27:     }
terom@27:   },
terom@27:   
terom@27:   startDrag: function(event) {
terom@27:     this.dragging = true;
terom@27:     if(!this.delta)
terom@27:       this.delta = this.currentDelta();
terom@27:     
terom@27:     if(this.options.zindex) {
terom@27:       this.originalZ = parseInt(Element.getStyle(this.element,'z-index') || 0);
terom@27:       this.element.style.zIndex = this.options.zindex;
terom@27:     }
terom@27:     
terom@27:     if(this.options.ghosting) {
terom@27:       this._clone = this.element.cloneNode(true);
terom@27:       this.element._originallyAbsolute = (this.element.getStyle('position') == 'absolute');
terom@27:       if (!this.element._originallyAbsolute)
terom@27:         Position.absolutize(this.element);
terom@27:       this.element.parentNode.insertBefore(this._clone, this.element);
terom@27:     }
terom@27:     
terom@27:     if(this.options.scroll) {
terom@27:       if (this.options.scroll == window) {
terom@27:         var where = this._getWindowScroll(this.options.scroll);
terom@27:         this.originalScrollLeft = where.left;
terom@27:         this.originalScrollTop = where.top;
terom@27:       } else {
terom@27:         this.originalScrollLeft = this.options.scroll.scrollLeft;
terom@27:         this.originalScrollTop = this.options.scroll.scrollTop;
terom@27:       }
terom@27:     }
terom@27:     
terom@27:     Draggables.notify('onStart', this, event);
terom@27:         
terom@27:     if(this.options.starteffect) this.options.starteffect(this.element);
terom@27:   },
terom@27:   
terom@27:   updateDrag: function(event, pointer) {
terom@27:     if(!this.dragging) this.startDrag(event);
terom@27:     
terom@27:     if(!this.options.quiet){
terom@27:       Position.prepare();
terom@27:       Droppables.show(pointer, this.element);
terom@27:     }
terom@27:     
terom@27:     Draggables.notify('onDrag', this, event);
terom@27:     
terom@27:     this.draw(pointer);
terom@27:     if(this.options.change) this.options.change(this);
terom@27:     
terom@27:     if(this.options.scroll) {
terom@27:       this.stopScrolling();
terom@27:       
terom@27:       var p;
terom@27:       if (this.options.scroll == window) {
terom@27:         with(this._getWindowScroll(this.options.scroll)) { p = [ left, top, left+width, top+height ]; }
terom@27:       } else {
terom@27:         p = Position.page(this.options.scroll);
terom@27:         p[0] += this.options.scroll.scrollLeft + Position.deltaX;
terom@27:         p[1] += this.options.scroll.scrollTop + Position.deltaY;
terom@27:         p.push(p[0]+this.options.scroll.offsetWidth);
terom@27:         p.push(p[1]+this.options.scroll.offsetHeight);
terom@27:       }
terom@27:       var speed = [0,0];
terom@27:       if(pointer[0] < (p[0]+this.options.scrollSensitivity)) speed[0] = pointer[0]-(p[0]+this.options.scrollSensitivity);
terom@27:       if(pointer[1] < (p[1]+this.options.scrollSensitivity)) speed[1] = pointer[1]-(p[1]+this.options.scrollSensitivity);
terom@27:       if(pointer[0] > (p[2]-this.options.scrollSensitivity)) speed[0] = pointer[0]-(p[2]-this.options.scrollSensitivity);
terom@27:       if(pointer[1] > (p[3]-this.options.scrollSensitivity)) speed[1] = pointer[1]-(p[3]-this.options.scrollSensitivity);
terom@27:       this.startScrolling(speed);
terom@27:     }
terom@27:     
terom@27:     // fix AppleWebKit rendering
terom@27:     if(Prototype.Browser.WebKit) window.scrollBy(0,0);
terom@27:     
terom@27:     Event.stop(event);
terom@27:   },
terom@27:   
terom@27:   finishDrag: function(event, success) {
terom@27:     this.dragging = false;
terom@27:     
terom@27:     if(this.options.quiet){
terom@27:       Position.prepare();
terom@27:       var pointer = [Event.pointerX(event), Event.pointerY(event)];
terom@27:       Droppables.show(pointer, this.element);
terom@27:     }
terom@27: 
terom@27:     if(this.options.ghosting) {
terom@27:       if (!this.element._originallyAbsolute)
terom@27:         Position.relativize(this.element);
terom@27:       delete this.element._originallyAbsolute;
terom@27:       Element.remove(this._clone);
terom@27:       this._clone = null;
terom@27:     }
terom@27: 
terom@27:     var dropped = false; 
terom@27:     if(success) { 
terom@27:       dropped = Droppables.fire(event, this.element); 
terom@27:       if (!dropped) dropped = false; 
terom@27:     }
terom@27:     if(dropped && this.options.onDropped) this.options.onDropped(this.element);
terom@27:     Draggables.notify('onEnd', this, event);
terom@27: 
terom@27:     var revert = this.options.revert;
terom@27:     if(revert && Object.isFunction(revert)) revert = revert(this.element);
terom@27:     
terom@27:     var d = this.currentDelta();
terom@27:     if(revert && this.options.reverteffect) {
terom@27:       if (dropped == 0 || revert != 'failure')
terom@27:         this.options.reverteffect(this.element,
terom@27:           d[1]-this.delta[1], d[0]-this.delta[0]);
terom@27:     } else {
terom@27:       this.delta = d;
terom@27:     }
terom@27: 
terom@27:     if(this.options.zindex)
terom@27:       this.element.style.zIndex = this.originalZ;
terom@27: 
terom@27:     if(this.options.endeffect) 
terom@27:       this.options.endeffect(this.element);
terom@27:       
terom@27:     Draggables.deactivate(this);
terom@27:     Droppables.reset();
terom@27:   },
terom@27:   
terom@27:   keyPress: function(event) {
terom@27:     if(event.keyCode!=Event.KEY_ESC) return;
terom@27:     this.finishDrag(event, false);
terom@27:     Event.stop(event);
terom@27:   },
terom@27:   
terom@27:   endDrag: function(event) {
terom@27:     if(!this.dragging) return;
terom@27:     this.stopScrolling();
terom@27:     this.finishDrag(event, true);
terom@27:     Event.stop(event);
terom@27:   },
terom@27:   
terom@27:   draw: function(point) {
terom@27:     var pos = Position.cumulativeOffset(this.element);
terom@27:     if(this.options.ghosting) {
terom@27:       var r   = Position.realOffset(this.element);
terom@27:       pos[0] += r[0] - Position.deltaX; pos[1] += r[1] - Position.deltaY;
terom@27:     }
terom@27:     
terom@27:     var d = this.currentDelta();
terom@27:     pos[0] -= d[0]; pos[1] -= d[1];
terom@27:     
terom@27:     if(this.options.scroll && (this.options.scroll != window && this._isScrollChild)) {
terom@27:       pos[0] -= this.options.scroll.scrollLeft-this.originalScrollLeft;
terom@27:       pos[1] -= this.options.scroll.scrollTop-this.originalScrollTop;
terom@27:     }
terom@27:     
terom@27:     var p = [0,1].map(function(i){ 
terom@27:       return (point[i]-pos[i]-this.offset[i]) 
terom@27:     }.bind(this));
terom@27:     
terom@27:     if(this.options.snap) {
terom@27:       if(Object.isFunction(this.options.snap)) {
terom@27:         p = this.options.snap(p[0],p[1],this);
terom@27:       } else {
terom@27:       if(Object.isArray(this.options.snap)) {
terom@27:         p = p.map( function(v, i) {
terom@27:           return (v/this.options.snap[i]).round()*this.options.snap[i] }.bind(this))
terom@27:       } else {
terom@27:         p = p.map( function(v) {
terom@27:           return (v/this.options.snap).round()*this.options.snap }.bind(this))
terom@27:       }
terom@27:     }}
terom@27:     
terom@27:     var style = this.element.style;
terom@27:     if((!this.options.constraint) || (this.options.constraint=='horizontal'))
terom@27:       style.left = p[0] + "px";
terom@27:     if((!this.options.constraint) || (this.options.constraint=='vertical'))
terom@27:       style.top  = p[1] + "px";
terom@27:     
terom@27:     if(style.visibility=="hidden") style.visibility = ""; // fix gecko rendering
terom@27:   },
terom@27:   
terom@27:   stopScrolling: function() {
terom@27:     if(this.scrollInterval) {
terom@27:       clearInterval(this.scrollInterval);
terom@27:       this.scrollInterval = null;
terom@27:       Draggables._lastScrollPointer = null;
terom@27:     }
terom@27:   },
terom@27:   
terom@27:   startScrolling: function(speed) {
terom@27:     if(!(speed[0] || speed[1])) return;
terom@27:     this.scrollSpeed = [speed[0]*this.options.scrollSpeed,speed[1]*this.options.scrollSpeed];
terom@27:     this.lastScrolled = new Date();
terom@27:     this.scrollInterval = setInterval(this.scroll.bind(this), 10);
terom@27:   },
terom@27:   
terom@27:   scroll: function() {
terom@27:     var current = new Date();
terom@27:     var delta = current - this.lastScrolled;
terom@27:     this.lastScrolled = current;
terom@27:     if(this.options.scroll == window) {
terom@27:       with (this._getWindowScroll(this.options.scroll)) {
terom@27:         if (this.scrollSpeed[0] || this.scrollSpeed[1]) {
terom@27:           var d = delta / 1000;
terom@27:           this.options.scroll.scrollTo( left + d*this.scrollSpeed[0], top + d*this.scrollSpeed[1] );
terom@27:         }
terom@27:       }
terom@27:     } else {
terom@27:       this.options.scroll.scrollLeft += this.scrollSpeed[0] * delta / 1000;
terom@27:       this.options.scroll.scrollTop  += this.scrollSpeed[1] * delta / 1000;
terom@27:     }
terom@27:     
terom@27:     Position.prepare();
terom@27:     Droppables.show(Draggables._lastPointer, this.element);
terom@27:     Draggables.notify('onDrag', this);
terom@27:     if (this._isScrollChild) {
terom@27:       Draggables._lastScrollPointer = Draggables._lastScrollPointer || $A(Draggables._lastPointer);
terom@27:       Draggables._lastScrollPointer[0] += this.scrollSpeed[0] * delta / 1000;
terom@27:       Draggables._lastScrollPointer[1] += this.scrollSpeed[1] * delta / 1000;
terom@27:       if (Draggables._lastScrollPointer[0] < 0)
terom@27:         Draggables._lastScrollPointer[0] = 0;
terom@27:       if (Draggables._lastScrollPointer[1] < 0)
terom@27:         Draggables._lastScrollPointer[1] = 0;
terom@27:       this.draw(Draggables._lastScrollPointer);
terom@27:     }
terom@27:     
terom@27:     if(this.options.change) this.options.change(this);
terom@27:   },
terom@27:   
terom@27:   _getWindowScroll: function(w) {
terom@27:     var T, L, W, H;
terom@27:     with (w.document) {
terom@27:       if (w.document.documentElement && documentElement.scrollTop) {
terom@27:         T = documentElement.scrollTop;
terom@27:         L = documentElement.scrollLeft;
terom@27:       } else if (w.document.body) {
terom@27:         T = body.scrollTop;
terom@27:         L = body.scrollLeft;
terom@27:       }
terom@27:       if (w.innerWidth) {
terom@27:         W = w.innerWidth;
terom@27:         H = w.innerHeight;
terom@27:       } else if (w.document.documentElement && documentElement.clientWidth) {
terom@27:         W = documentElement.clientWidth;
terom@27:         H = documentElement.clientHeight;
terom@27:       } else {
terom@27:         W = body.offsetWidth;
terom@27:         H = body.offsetHeight
terom@27:       }
terom@27:     }
terom@27:     return { top: T, left: L, width: W, height: H };
terom@27:   }
terom@27: });
terom@27: 
terom@27: Draggable._dragging = { };
terom@27: 
terom@27: /*--------------------------------------------------------------------------*/
terom@27: 
terom@27: var SortableObserver = Class.create({
terom@27:   initialize: function(element, observer) {
terom@27:     this.element   = $(element);
terom@27:     this.observer  = observer;
terom@27:     this.lastValue = Sortable.serialize(this.element);
terom@27:   },
terom@27:   
terom@27:   onStart: function() {
terom@27:     this.lastValue = Sortable.serialize(this.element);
terom@27:   },
terom@27:   
terom@27:   onEnd: function() {
terom@27:     Sortable.unmark();
terom@27:     if(this.lastValue != Sortable.serialize(this.element))
terom@27:       this.observer(this.element)
terom@27:   }
terom@27: });
terom@27: 
terom@27: var Sortable = {
terom@27:   SERIALIZE_RULE: /^[^_\-](?:[A-Za-z0-9\-\_]*)[_](.*)$/,
terom@27:   
terom@27:   sortables: { },
terom@27:   
terom@27:   _findRootElement: function(element) {
terom@27:     while (element.tagName.toUpperCase() != "BODY") {  
terom@27:       if(element.id && Sortable.sortables[element.id]) return element;
terom@27:       element = element.parentNode;
terom@27:     }
terom@27:   },
terom@27: 
terom@27:   options: function(element) {
terom@27:     element = Sortable._findRootElement($(element));
terom@27:     if(!element) return;
terom@27:     return Sortable.sortables[element.id];
terom@27:   },
terom@27:   
terom@27:   destroy: function(element){
terom@27:     var s = Sortable.options(element);
terom@27:     
terom@27:     if(s) {
terom@27:       Draggables.removeObserver(s.element);
terom@27:       s.droppables.each(function(d){ Droppables.remove(d) });
terom@27:       s.draggables.invoke('destroy');
terom@27:       
terom@27:       delete Sortable.sortables[s.element.id];
terom@27:     }
terom@27:   },
terom@27: 
terom@27:   create: function(element) {
terom@27:     element = $(element);
terom@27:     var options = Object.extend({ 
terom@27:       element:     element,
terom@27:       tag:         'li',       // assumes li children, override with tag: 'tagname'
terom@27:       dropOnEmpty: false,
terom@27:       tree:        false,
terom@27:       treeTag:     'ul',
terom@27:       overlap:     'vertical', // one of 'vertical', 'horizontal'
terom@27:       constraint:  'vertical', // one of 'vertical', 'horizontal', false
terom@27:       containment: element,    // also takes array of elements (or id's); or false
terom@27:       handle:      false,      // or a CSS class
terom@27:       only:        false,
terom@27:       delay:       0,
terom@27:       hoverclass:  null,
terom@27:       ghosting:    false,
terom@27:       quiet:       false, 
terom@27:       scroll:      false,
terom@27:       scrollSensitivity: 20,
terom@27:       scrollSpeed: 15,
terom@27:       format:      this.SERIALIZE_RULE,
terom@27:       
terom@27:       // these take arrays of elements or ids and can be 
terom@27:       // used for better initialization performance
terom@27:       elements:    false,
terom@27:       handles:     false,
terom@27:       
terom@27:       onChange:    Prototype.emptyFunction,
terom@27:       onUpdate:    Prototype.emptyFunction
terom@27:     }, arguments[1] || { });
terom@27: 
terom@27:     // clear any old sortable with same element
terom@27:     this.destroy(element);
terom@27: 
terom@27:     // build options for the draggables
terom@27:     var options_for_draggable = {
terom@27:       revert:      true,
terom@27:       quiet:       options.quiet,
terom@27:       scroll:      options.scroll,
terom@27:       scrollSpeed: options.scrollSpeed,
terom@27:       scrollSensitivity: options.scrollSensitivity,
terom@27:       delay:       options.delay,
terom@27:       ghosting:    options.ghosting,
terom@27:       constraint:  options.constraint,
terom@27:       handle:      options.handle };
terom@27: 
terom@27:     if(options.starteffect)
terom@27:       options_for_draggable.starteffect = options.starteffect;
terom@27: 
terom@27:     if(options.reverteffect)
terom@27:       options_for_draggable.reverteffect = options.reverteffect;
terom@27:     else
terom@27:       if(options.ghosting) options_for_draggable.reverteffect = function(element) {
terom@27:         element.style.top  = 0;
terom@27:         element.style.left = 0;
terom@27:       };
terom@27: 
terom@27:     if(options.endeffect)
terom@27:       options_for_draggable.endeffect = options.endeffect;
terom@27: 
terom@27:     if(options.zindex)
terom@27:       options_for_draggable.zindex = options.zindex;
terom@27: 
terom@27:     // build options for the droppables  
terom@27:     var options_for_droppable = {
terom@27:       overlap:     options.overlap,
terom@27:       containment: options.containment,
terom@27:       tree:        options.tree,
terom@27:       hoverclass:  options.hoverclass,
terom@27:       onHover:     Sortable.onHover
terom@27:     }
terom@27:     
terom@27:     var options_for_tree = {
terom@27:       onHover:      Sortable.onEmptyHover,
terom@27:       overlap:      options.overlap,
terom@27:       containment:  options.containment,
terom@27:       hoverclass:   options.hoverclass
terom@27:     }
terom@27: 
terom@27:     // fix for gecko engine
terom@27:     Element.cleanWhitespace(element); 
terom@27: 
terom@27:     options.draggables = [];
terom@27:     options.droppables = [];
terom@27: 
terom@27:     // drop on empty handling
terom@27:     if(options.dropOnEmpty || options.tree) {
terom@27:       Droppables.add(element, options_for_tree);
terom@27:       options.droppables.push(element);
terom@27:     }
terom@27: 
terom@27:     (options.elements || this.findElements(element, options) || []).each( function(e,i) {
terom@27:       var handle = options.handles ? $(options.handles[i]) :
terom@27:         (options.handle ? $(e).select('.' + options.handle)[0] : e); 
terom@27:       options.draggables.push(
terom@27:         new Draggable(e, Object.extend(options_for_draggable, { handle: handle })));
terom@27:       Droppables.add(e, options_for_droppable);
terom@27:       if(options.tree) e.treeNode = element;
terom@27:       options.droppables.push(e);      
terom@27:     });
terom@27:     
terom@27:     if(options.tree) {
terom@27:       (Sortable.findTreeElements(element, options) || []).each( function(e) {
terom@27:         Droppables.add(e, options_for_tree);
terom@27:         e.treeNode = element;
terom@27:         options.droppables.push(e);
terom@27:       });
terom@27:     }
terom@27: 
terom@27:     // keep reference
terom@27:     this.sortables[element.id] = options;
terom@27: 
terom@27:     // for onupdate
terom@27:     Draggables.addObserver(new SortableObserver(element, options.onUpdate));
terom@27: 
terom@27:   },
terom@27: 
terom@27:   // return all suitable-for-sortable elements in a guaranteed order
terom@27:   findElements: function(element, options) {
terom@27:     return Element.findChildren(
terom@27:       element, options.only, options.tree ? true : false, options.tag);
terom@27:   },
terom@27:   
terom@27:   findTreeElements: function(element, options) {
terom@27:     return Element.findChildren(
terom@27:       element, options.only, options.tree ? true : false, options.treeTag);
terom@27:   },
terom@27: 
terom@27:   onHover: function(element, dropon, overlap) {
terom@27:     if(Element.isParent(dropon, element)) return;
terom@27: 
terom@27:     if(overlap > .33 && overlap < .66 && Sortable.options(dropon).tree) {
terom@27:       return;
terom@27:     } else if(overlap>0.5) {
terom@27:       Sortable.mark(dropon, 'before');
terom@27:       if(dropon.previousSibling != element) {
terom@27:         var oldParentNode = element.parentNode;
terom@27:         element.style.visibility = "hidden"; // fix gecko rendering
terom@27:         dropon.parentNode.insertBefore(element, dropon);
terom@27:         if(dropon.parentNode!=oldParentNode) 
terom@27:           Sortable.options(oldParentNode).onChange(element);
terom@27:         Sortable.options(dropon.parentNode).onChange(element);
terom@27:       }
terom@27:     } else {
terom@27:       Sortable.mark(dropon, 'after');
terom@27:       var nextElement = dropon.nextSibling || null;
terom@27:       if(nextElement != element) {
terom@27:         var oldParentNode = element.parentNode;
terom@27:         element.style.visibility = "hidden"; // fix gecko rendering
terom@27:         dropon.parentNode.insertBefore(element, nextElement);
terom@27:         if(dropon.parentNode!=oldParentNode) 
terom@27:           Sortable.options(oldParentNode).onChange(element);
terom@27:         Sortable.options(dropon.parentNode).onChange(element);
terom@27:       }
terom@27:     }
terom@27:   },
terom@27:   
terom@27:   onEmptyHover: function(element, dropon, overlap) {
terom@27:     var oldParentNode = element.parentNode;
terom@27:     var droponOptions = Sortable.options(dropon);
terom@27:         
terom@27:     if(!Element.isParent(dropon, element)) {
terom@27:       var index;
terom@27:       
terom@27:       var children = Sortable.findElements(dropon, {tag: droponOptions.tag, only: droponOptions.only});
terom@27:       var child = null;
terom@27:             
terom@27:       if(children) {
terom@27:         var offset = Element.offsetSize(dropon, droponOptions.overlap) * (1.0 - overlap);
terom@27:         
terom@27:         for (index = 0; index < children.length; index += 1) {
terom@27:           if (offset - Element.offsetSize (children[index], droponOptions.overlap) >= 0) {
terom@27:             offset -= Element.offsetSize (children[index], droponOptions.overlap);
terom@27:           } else if (offset - (Element.offsetSize (children[index], droponOptions.overlap) / 2) >= 0) {
terom@27:             child = index + 1 < children.length ? children[index + 1] : null;
terom@27:             break;
terom@27:           } else {
terom@27:             child = children[index];
terom@27:             break;
terom@27:           }
terom@27:         }
terom@27:       }
terom@27:       
terom@27:       dropon.insertBefore(element, child);
terom@27:       
terom@27:       Sortable.options(oldParentNode).onChange(element);
terom@27:       droponOptions.onChange(element);
terom@27:     }
terom@27:   },
terom@27: 
terom@27:   unmark: function() {
terom@27:     if(Sortable._marker) Sortable._marker.hide();
terom@27:   },
terom@27: 
terom@27:   mark: function(dropon, position) {
terom@27:     // mark on ghosting only
terom@27:     var sortable = Sortable.options(dropon.parentNode);
terom@27:     if(sortable && !sortable.ghosting) return; 
terom@27: 
terom@27:     if(!Sortable._marker) {
terom@27:       Sortable._marker = 
terom@27:         ($('dropmarker') || Element.extend(document.createElement('DIV'))).
terom@27:           hide().addClassName('dropmarker').setStyle({position:'absolute'});
terom@27:       document.getElementsByTagName("body").item(0).appendChild(Sortable._marker);
terom@27:     }    
terom@27:     var offsets = Position.cumulativeOffset(dropon);
terom@27:     Sortable._marker.setStyle({left: offsets[0]+'px', top: offsets[1] + 'px'});
terom@27:     
terom@27:     if(position=='after')
terom@27:       if(sortable.overlap == 'horizontal') 
terom@27:         Sortable._marker.setStyle({left: (offsets[0]+dropon.clientWidth) + 'px'});
terom@27:       else
terom@27:         Sortable._marker.setStyle({top: (offsets[1]+dropon.clientHeight) + 'px'});
terom@27:     
terom@27:     Sortable._marker.show();
terom@27:   },
terom@27:   
terom@27:   _tree: function(element, options, parent) {
terom@27:     var children = Sortable.findElements(element, options) || [];
terom@27:   
terom@27:     for (var i = 0; i < children.length; ++i) {
terom@27:       var match = children[i].id.match(options.format);
terom@27: 
terom@27:       if (!match) continue;
terom@27:       
terom@27:       var child = {
terom@27:         id: encodeURIComponent(match ? match[1] : null),
terom@27:         element: element,
terom@27:         parent: parent,
terom@27:         children: [],
terom@27:         position: parent.children.length,
terom@27:         container: $(children[i]).down(options.treeTag)
terom@27:       }
terom@27:       
terom@27:       /* Get the element containing the children and recurse over it */
terom@27:       if (child.container)
terom@27:         this._tree(child.container, options, child)
terom@27:       
terom@27:       parent.children.push (child);
terom@27:     }
terom@27: 
terom@27:     return parent; 
terom@27:   },
terom@27: 
terom@27:   tree: function(element) {
terom@27:     element = $(element);
terom@27:     var sortableOptions = this.options(element);
terom@27:     var options = Object.extend({
terom@27:       tag: sortableOptions.tag,
terom@27:       treeTag: sortableOptions.treeTag,
terom@27:       only: sortableOptions.only,
terom@27:       name: element.id,
terom@27:       format: sortableOptions.format
terom@27:     }, arguments[1] || { });
terom@27:     
terom@27:     var root = {
terom@27:       id: null,
terom@27:       parent: null,
terom@27:       children: [],
terom@27:       container: element,
terom@27:       position: 0
terom@27:     }
terom@27:     
terom@27:     return Sortable._tree(element, options, root);
terom@27:   },
terom@27: 
terom@27:   /* Construct a [i] index for a particular node */
terom@27:   _constructIndex: function(node) {
terom@27:     var index = '';
terom@27:     do {
terom@27:       if (node.id) index = '[' + node.position + ']' + index;
terom@27:     } while ((node = node.parent) != null);
terom@27:     return index;
terom@27:   },
terom@27: 
terom@27:   sequence: function(element) {
terom@27:     element = $(element);
terom@27:     var options = Object.extend(this.options(element), arguments[1] || { });
terom@27:     
terom@27:     return $(this.findElements(element, options) || []).map( function(item) {
terom@27:       return item.id.match(options.format) ? item.id.match(options.format)[1] : '';
terom@27:     });
terom@27:   },
terom@27: 
terom@27:   setSequence: function(element, new_sequence) {
terom@27:     element = $(element);
terom@27:     var options = Object.extend(this.options(element), arguments[2] || { });
terom@27:     
terom@27:     var nodeMap = { };
terom@27:     this.findElements(element, options).each( function(n) {
terom@27:         if (n.id.match(options.format))
terom@27:             nodeMap[n.id.match(options.format)[1]] = [n, n.parentNode];
terom@27:         n.parentNode.removeChild(n);
terom@27:     });
terom@27:    
terom@27:     new_sequence.each(function(ident) {
terom@27:       var n = nodeMap[ident];
terom@27:       if (n) {
terom@27:         n[1].appendChild(n[0]);
terom@27:         delete nodeMap[ident];
terom@27:       }
terom@27:     });
terom@27:   },
terom@27:   
terom@27:   serialize: function(element) {
terom@27:     element = $(element);
terom@27:     var options = Object.extend(Sortable.options(element), arguments[1] || { });
terom@27:     var name = encodeURIComponent(
terom@27:       (arguments[1] && arguments[1].name) ? arguments[1].name : element.id);
terom@27:     
terom@27:     if (options.tree) {
terom@27:       return Sortable.tree(element, arguments[1]).children.map( function (item) {
terom@27:         return [name + Sortable._constructIndex(item) + "[id]=" + 
terom@27:                 encodeURIComponent(item.id)].concat(item.children.map(arguments.callee));
terom@27:       }).flatten().join('&');
terom@27:     } else {
terom@27:       return Sortable.sequence(element, arguments[1]).map( function(item) {
terom@27:         return name + "[]=" + encodeURIComponent(item);
terom@27:       }).join('&');
terom@27:     }
terom@27:   }
terom@27: }
terom@27: 
terom@27: // Returns true if child is contained within element
terom@27: Element.isParent = function(child, element) {
terom@27:   if (!child.parentNode || child == element) return false;
terom@27:   if (child.parentNode == element) return true;
terom@27:   return Element.isParent(child.parentNode, element);
terom@27: }
terom@27: 
terom@27: Element.findChildren = function(element, only, recursive, tagName) {   
terom@27:   if(!element.hasChildNodes()) return null;
terom@27:   tagName = tagName.toUpperCase();
terom@27:   if(only) only = [only].flatten();
terom@27:   var elements = [];
terom@27:   $A(element.childNodes).each( function(e) {
terom@27:     if(e.tagName && e.tagName.toUpperCase()==tagName &&
terom@27:       (!only || (Element.classNames(e).detect(function(v) { return only.include(v) }))))
terom@27:         elements.push(e);
terom@27:     if(recursive) {
terom@27:       var grandchildren = Element.findChildren(e, only, recursive, tagName);
terom@27:       if(grandchildren) elements.push(grandchildren);
terom@27:     }
terom@27:   });
terom@27: 
terom@27:   return (elements.length>0 ? elements.flatten() : []);
terom@27: }
terom@27: 
terom@27: Element.offsetSize = function (element, type) {
terom@27:   return element['offset' + ((type=='vertical' || type=='height') ? 'Height' : 'Width')];
terom@27: }