/*
 * jQuery UI Sortable @VERSION
 *
 * Copyright (c) 2008 AUTHORS.txt (http://ui.jquery.com/about)
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 *
 * http://docs.jquery.com/UI/Sortables
 *
 * Depends:
 *	ui.core.js
 */
(function($) {

$.widget("ui.sortable", $.extend({}, $.ui.mouse, {
	_init: function() {

		var o = this.options;
		this.containerCache = {};
		this.element.addClass("ui-sortable");

		//Get the items
		this.refresh();

		//Let's determine if the items are floating
		this.floating = this.items.length ? (/left|right/).test(this.items[0].item.css('float')) : false;

		//Let's determine the parent's offset
		this.offset = this.element.offset();

		//Initialize mouse events for interaction
		this._mouseInit();

	},

	destroy: function() {
		this.element
			.removeClass("ui-sortable ui-sortable-disabled")
			.removeData("sortable")
			.unbind(".sortable");
		this._mouseDestroy();

		for ( var i = this.items.length - 1; i >= 0; i-- )
			this.items[i].item.removeData("sortable-item");
	},

	_mouseCapture: function(event, overrideHandle) {

		if (this.reverting) {
			return false;
		}

		if(this.options.disabled || this.options.type == 'static') return false;

		//We have to refresh the items data once first
		this._refreshItems(event);

		//Find out if the clicked node (or one of its parents) is a actual item in this.items
		var currentItem = null, self = this, nodes = $(event.target).parents().each(function() {
			if($.data(this, 'sortable-item') == self) {
				currentItem = $(this);
				return false;
			}
		});
		if($.data(event.target, 'sortable-item') == self) currentItem = $(event.target);

		if(!currentItem) return false;
		if(this.options.handle && !overrideHandle) {
			var validHandle = false;

			$(this.options.handle, currentItem).find("*").andSelf().each(function() { if(this == event.target) validHandle = true; });
			if(!validHandle) return false;
		}

		this.currentItem = currentItem;
		this._removeCurrentsFromItems();
		return true;

	},

	_mouseStart: function(event, overrideHandle, noActivation) {

		var o = this.options;
		this.currentContainer = this;

		//We only need to call refreshPositions, because the refreshItems call has been moved to mouseCapture
		this.refreshPositions();

		//Create and append the visible helper
		this.helper = this.createHelper(event);

		/*
		 * - Position generation -
		 * This block generates everything position related - it's the core of draggables.
		 */

		this.margins = {																				//Cache the margins
			left: (parseInt(this.currentItem.css("marginLeft"),10) || 0),
			top: (parseInt(this.currentItem.css("marginTop"),10) || 0)
		};

		this.offset = this.currentItem.offset();														//The element's absolute position on the page
		this.offset = {																					//Substract the margins from the element's absolute offset
			top: this.offset.top - this.margins.top,
			left: this.offset.left - this.margins.left
		};

		this.offset.click = {																			//Where the click happened, relative to the element
			left: event.pageX - this.offset.left,
			top: event.pageY - this.offset.top
		};

		this.offsetParent = this.helper.offsetParent();													//Get the offsetParent and cache its position
		var po = this.offsetParent.offset();

		this.offsetParentBorders = {
			top: (parseInt(this.offsetParent.css("borderTopWidth"),10) || 0),
			left: (parseInt(this.offsetParent.css("borderLeftWidth"),10) || 0)
		};

		this.offset.parent = {																			//Store its position plus border
			top: po.top + this.offsetParentBorders.top,
			left: po.left + this.offsetParentBorders.left
		};

		this.originalPosition = this._generatePosition(event);				//Generate the original position
		this.domPosition = { prev: this.currentItem.prev()[0], parent: this.currentItem.parent()[0] };  //Cache the former DOM position

		//If o.placeholder is used, create a new element at the given position with the class
		this.helperProportions = { width: this.helper.outerWidth(), height: this.helper.outerHeight() };//Cache the helper size

		if(o.helper == "original") {
			this._storedCSS = { position: this.currentItem.css("position"), top: this.currentItem.css("top"), left: this.currentItem.css("left"), clear: this.currentItem.css("clear") };
		} else {
			this.currentItem.hide(); //Hide the original, won't cause anything bad this way
		}

		//Position it absolutely and add a helper class
		this.helper
			.css({ position: 'absolute', clear: 'both' })
			.addClass('ui-sortable-helper');

		//Create the placeholder
		this._createPlaceholder();

		//Call plugins and callbacks
		this._propagate("start", event);

		//Recache the helper size
		if(!this._preserveHelperProportions)
			this.helperProportions = { width: this.helper.outerWidth(), height: this.helper.outerHeight() };

		if(o.cursorAt) {
			if(o.cursorAt.left != undefined) this.offset.click.left = o.cursorAt.left;
			if(o.cursorAt.right != undefined) this.offset.click.left = this.helperProportions.width - o.cursorAt.right;
			if(o.cursorAt.top != undefined) this.offset.click.top = o.cursorAt.top;
			if(o.cursorAt.bottom != undefined) this.offset.click.top = this.helperProportions.height - o.cursorAt.bottom;
		}

		/*
		 * - Position constraining -
		 * Here we prepare position constraining like grid and containment.
		 */

		if(o.containment) {
			if(o.containment == 'parent') o.containment = this.helper[0].parentNode;
			if(o.containment == 'document' || o.containment == 'window') this.containment = [
				0 - this.offset.parent.left,
				0 - this.offset.parent.top,
				$(o.containment == 'document' ? document : window).width() - this.offset.parent.left - this.helperProportions.width - this.margins.left - (parseInt(this.element.css("marginRight"),10) || 0),
				($(o.containment == 'document' ? document : window).height() || document.body.parentNode.scrollHeight) - this.offset.parent.top - this.helperProportions.height - this.margins.top - (parseInt(this.element.css("marginBottom"),10) || 0)
			];

			if(!(/^(document|window|parent)$/).test(o.containment)) {
				var ce = $(o.containment)[0];
				var co = $(o.containment).offset();
				var over = ($(ce).css("overflow") != 'hidden');

				this.containment = [
					co.left + (parseInt($(ce).css("borderLeftWidth"),10) || 0) - this.offset.parent.left,
					co.top + (parseInt($(ce).css("borderTopWidth"),10) || 0) - this.offset.parent.top,
					co.left+(over ? Math.max(ce.scrollWidth,ce.offsetWidth) : ce.offsetWidth) - (parseInt($(ce).css("borderLeftWidth"),10) || 0) - this.offset.parent.left - this.helperProportions.width - this.margins.left - (parseInt(this.currentItem.css("marginRight"),10) || 0),
					co.top+(over ? Math.max(ce.scrollHeight,ce.offsetHeight) : ce.offsetHeight) - (parseInt($(ce).css("borderTopWidth"),10) || 0) - this.offset.parent.top - this.helperProportions.height - this.margins.top - (parseInt(this.currentItem.css("marginBottom"),10) || 0)
				];
			}
		}

		//Post 'activate' events to possible containers
		if(!noActivation) {
			 for (var i = this.containers.length - 1; i >= 0; i--) { this.containers[i]._propagate("activate", event, this); }
		}

		//Prepare possible droppables
		if($.ui.ddmanager)
			$.ui.ddmanager.current = this;

		if ($.ui.ddmanager && !o.dropBehaviour)
			$.ui.ddmanager.prepareOffsets(this, event);

		this.dragging = true;

		this._mouseDrag(event); //Execute the drag once - this causes the helper not to be visible before getting its correct position
		return true;

	},

	_mouseDrag: function(event) {
		//Compute the helpers position
		this.position = this._generatePosition(event);
		this.positionAbs = this._convertPositionTo("absolute");

		if (!this.lastPositionAbs) {
			this.lastPositionAbs = this.positionAbs;
		}

		//Call the internal plugins
		$.ui.plugin.call(this, "sort", [event, this._ui()]);

		//Regenerate the absolute position used for position checks
		this.positionAbs = this._convertPositionTo("absolute");

		//Set the helper's position
		if (this.helper) {
			this.helper[0].style.left = this.position.left+'px';
			this.helper[0].style.top = this.position.top+'px';
		}
		//Rearrange
		for (var i = this.items.length - 1; i >= 0; i--) {

			var item = this.items[i], intersection = this._intersectsWithPointer(item);

			if (!intersection) continue;

			var itemChecked = this.items[i].item[0];

			if(itemChecked != this.currentItem[0] //cannot intersect with itself
				&&	this.placeholder[intersection == 1 ? "next" : "prev"]()[0] != itemChecked //no useless actions that have been done before
				&&	!$.ui.contains(this.placeholder[0], itemChecked) //no action if the item moved is the parent of the item checked
				&& (this.options.type == 'semi-dynamic' ? !$.ui.contains(this.element[0], itemChecked) : true)
			) {

				this.direction = intersection == 1 ? "down" : "up";

				if (this.options.tolerance == "pointer") {
					this.options.sortIndicator.call(this, event, item);
				}
				else if (this.options.tolerance == "guess" && this._intersectsGuess(item)) {
					this.options.sortIndicator.call(this, event, item);
				}

				this._propagate("change", event); //Call plugins and callbacks
				break;
			}
		}

		//Post events to containers
		this._contactContainers(event);

		//Interconnect with droppables
		if($.ui.ddmanager) $.ui.ddmanager.drag(this, event);

		//Call callbacks
		this.element.triggerHandler("sort", [event, this._ui()], this.options["sort"]);

		this.lastPositionAbs = this.positionAbs;

		return false;

	},

	_mouseStop: function(event, noPropagation) {

		if(!event) return;

		//If we are using droppables, inform the manager about the drop
		if ($.ui.ddmanager && !this.options.dropBehaviour)
			$.ui.ddmanager.drop(this, event);

		if(this.options.revert) {
			var self = this;
			var cur = self.placeholder.offset();

			self.reverting = true;

			$(this.helper).animate({
				left: cur.left - this.offset.parent.left - self.margins.left + (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollLeft),
				top: cur.top - this.offset.parent.top - self.margins.top + (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollTop)
			}, parseInt(this.options.revert, 10) || 500, function() {
				self._clear(event);
			});
		} else {
			this._clear(event, noPropagation);
		}

		return false;

	},

	cancel: function() {

		if(this.dragging) {

			this._mouseUp();

			if(this.options.helper == "original")
				this.currentItem.css(this._storedCSS).removeClass("ui-sortable-helper");
			else
				this.currentItem.show();

			//Post deactivating events to containers
			for (var i = this.containers.length - 1; i >= 0; i--){
				this.containers[i]._propagate("deactivate", null, this);
				if(this.containers[i].containerCache.over) {
					this.containers[i]._propagate("out", null, this);
					this.containers[i].containerCache.over = 0;
				}
			}

		}

		//$(this.placeholder[0]).remove(); would have been the jQuery way - unfortunately, it unbinds ALL events from the original node!
		if(this.placeholder[0].parentNode) this.placeholder[0].parentNode.removeChild(this.placeholder[0]);
		if(this.options.helper != "original" && this.helper && this.helper[0].parentNode) this.helper.remove();

		$.extend(this, {
			helper: null,
			dragging: false,
			reverting: false,
			_noFinalSort: null
		});

		if(this.domPosition.prev) {
			$(this.domPosition.prev).after(this.currentItem);
		} else {
			$(this.domPosition.parent).prepend(this.currentItem);
		}

		return true;

	},

	serialize: function(o) {

		var items = this._getItemsAsjQuery(o && o.connected);
		var str = []; o = o || {};

		$(items).each(function() {
			var res = ($(o.item || this).attr(o.attribute || 'id') || '').match(o.expression || (/(.+)[-=_](.+)/));
			if(res) str.push((o.key || res[1]+'[]')+'='+(o.key && o.expression ? res[1] : res[2]));
		});

		return str.join('&');

	},

	toArray: function(o) {

		var items = this._getItemsAsjQuery(o && o.connected);
		var ret = []; o = o || {};

		items.each(function() { ret.push($(o.item || this).attr(o.attribute || 'id') || ''); });
		return ret;

	},

	/* Be careful with the following core functions */
	_intersectsWith: function(item) {
		var x1 = this.positionAbs.left, x2 = x1 + this.helperProportions.width,
		y1 = this.positionAbs.top, y2 = y1 + this.helperProportions.height;
		var l = item.left, r = l + item.width,
		t = item.top, b = t + item.height;

		var dyClick = this.offset.click.top, dxClick = this.offset.click.left;
		var isOverElement = (y1 + dyClick) > t && (y1 + dyClick) < b && (x1 + dxClick) > l && (x1 + dxClick) < r;

		if(this.options.tolerance == "pointer" || this.options.forcePointerForContainers || (this.options.tolerance == "guess" && this.helperProportions[this.floating ? 'width' : 'height'] > item[this.floating ? 'width' : 'height'])) {
			return isOverElement;
		} else {

			return (l < x1 + (this.helperProportions.width / 2) // Right Half
				&& x2 - (this.helperProportions.width / 2) < r // Left Half
				&& t < y1 + (this.helperProportions.height / 2) // Bottom Half
				&& y2 - (this.helperProportions.height / 2) < b ); // Top Half

		}
	},

	_intersectsWithPointer: function(item) {
		var dyClick = this.offset.click.top, dxClick = this.offset.click.left;
		var helperTop = this.positionAbs.top, helperLeft = this.positionAbs.left;
		var itemHeight = item.height, itemWidth = item.width;
		var itemTop = item.top, itemLeft = item.left;

		if (this.cancelIntersection) {
			return false;
		}

		var isOverElementHeight = $.ui.isOverAxis(helperTop + dyClick, itemTop, itemHeight);
		var isOverElementWidth = $.ui.isOverAxis(helperLeft + dxClick, itemLeft, itemWidth);
		var isOverElement = isOverElementHeight && isOverElementWidth;
		var verticalDirection = this._getDragVerticalDirection();
		var horizontalDirection = this._getDragHorizontalDirection();

		if (!isOverElement) return false;

		if (this.floating) {

			if (!horizontalDirection) {
				return verticalDirection == "down" ? 2 : 1;
			}

			return horizontalDirection == "right" ? 2 : 1;
		}
		else {

			if (!verticalDirection) {
				return false;
			}

			return verticalDirection == "down" ? 2 : 1;
		}

		return false;
	},

	_intersectsGuess: function(item) {
		var dyClick = this.offset.click.top, dxClick = this.offset.click.left;
		var helperTop = this.positionAbs.top, helperLeft = this.positionAbs.left;
		var itemHeight = item.height, itemWidth = item.width;
		var itemTop = item.top, itemLeft = item.left;

		var isOverBottomHalf = $.ui.isOverAxis(helperTop + dyClick, itemTop + (itemHeight/2), itemHeight);
		var isOverTopHalf = !isOverBottomHalf;
		var isOverRightHalf = $.ui.isOverAxis(helperLeft + dxClick, itemLeft + (itemWidth/2), itemWidth);
		var isOverLeftHalf = !isOverRightHalf;
		var verticalDirection = this._getDragVerticalDirection();
		var horizontalDirection = this._getDragHorizontalDirection();

		var verticalIntersection = function() {
			if (!verticalDirection) {
				return false;
			}
			if (verticalDirection == "down" && isOverBottomHalf ||
				verticalDirection == "up" && isOverTopHalf) {
				return true;
			}
		};

		var horizontalIntersection = function() {
			if (!horizontalDirection) {
				return verticalIntersection();
			}
			if (horizontalDirection == "left" && isOverLeftHalf ||
				horizontalDirection == "right" && isOverRightHalf) {
				return true;
			}
		};

		if (this.floating) {
			return horizontalIntersection();
		}
		else {
			return verticalIntersection();
		}

		return false;
	},

	_getDragVerticalDirection: function() {
		var helperTop = this.positionAbs.top;
		var lastTop = this.lastPositionAbs.top;
		var delta = helperTop - lastTop;

		if (delta == 0) {
			return false;
		}

		var direction = delta > 0 ? "down" : "up";
		return direction;
	},

	_getDragHorizontalDirection: function() {
		var helperLeft = this.positionAbs.left;
		var lastLeft = this.lastPositionAbs.left;
		var delta = helperLeft - lastLeft;

		if (delta == 0) {
			return false;
		}

		var direction = delta > 0 ? "right" : "left";
		return direction;
	},

	refresh: function(event) {
		this._refreshItems(event);
		this.refreshPositions();
	},

	_getItemsAsjQuery: function(connected) {

		var self = this;
		var items = [];
		var queries = [];

		if(this.options.connectWith && connected) {
			for (var i = this.options.connectWith.length - 1; i >= 0; i--){
				var cur = $(this.options.connectWith[i]);
				for (var j = cur.length - 1; j >= 0; j--){
					var inst = $.data(cur[j], 'sortable');
					if(inst && inst != this && !inst.options.disabled) {
						queries.push([$.isFunction(inst.options.items) ? inst.options.items.call(inst.element) : $(inst.options.items, inst.element).not(".ui-sortable-helper"), inst]);
					}
				};
			};
		}

		queries.push([$.isFunction(this.options.items) ? this.options.items.call(this.element, null, { options: this.options, item: this.currentItem }) : $(this.options.items, this.element).not(".ui-sortable-helper"), this]);

		for (var i = queries.length - 1; i >= 0; i--){
			queries[i][0].each(function() {
				items.push(this);
			});
		};

		return $(items);

	},

	_removeCurrentsFromItems: function() {

		var list = this.currentItem.find(":data(sortable-item)");

		for (var i=0; i < this.items.length; i++) {

			for (var j=0; j < list.length; j++) {
				if(list[j] == this.items[i].item[0])
					this.items.splice(i,1);
			};

		};

	},

	_refreshItems: function(event) {

		this.items = [];
		this.containers = [this];
		var items = this.items;
		var self = this;
		var queries = [[$.isFunction(this.options.items) ? this.options.items.call(this.element[0], event, { item: this.currentItem }) : $(this.options.items, this.element), this]];

		if(this.options.connectWith) {
			for (var i = this.options.connectWith.length - 1; i >= 0; i--){
				var cur = $(this.options.connectWith[i]);
				for (var j = cur.length - 1; j >= 0; j--){
					var inst = $.data(cur[j], 'sortable');
					if(inst && inst != this && !inst.options.disabled) {
						queries.push([$.isFunction(inst.options.items) ? inst.options.items.call(inst.element[0], event, { item: this.currentItem }) : $(inst.options.items, inst.element), inst]);
						this.containers.push(inst);
					}
				};
			};
		}

		for (var i = queries.length - 1; i >= 0; i--) {
			var targetData = queries[i][1];
			var _queries = queries[i][0];

			for (var j=0, queriesLength = _queries.length; j < queriesLength; j++) {
				var item = $(_queries[j]);

				item.data('sortable-item', targetData); // Data for target checking (mouse manager)

				items.push({
					item: item,
					instance: targetData,
					width: 0, height: 0,
					left: 0, top: 0
				});
			};
		};

	},

	refreshPositions: function(fast) {

		//This has to be redone because due to the item being moved out/into the offsetParent, the offsetParent's position will change
		if(this.offsetParent) {
			var po = this.offsetParent.offset();
			this.offset.parent = { top: po.top + this.offsetParentBorders.top, left: po.left + this.offsetParentBorders.left };
		}

		for (var i = this.items.length - 1; i >= 0; i--){
			var item = this.items[i];

			//We ignore calculating positions of all connected containers when we're not over them
			if(item.instance != this.currentContainer && this.currentContainer && item.item[0] != this.currentItem[0])
				continue;

			var t = this.options.toleranceElement ? $(this.options.toleranceElement, item.item) : item.item;

			if (!fast) {
				if (this.options.accurate) {
					item.width = t.width();
					item.height = t.height();
				}
				else {
					item.width = t[0].offsetWidth;
					item.height = t[0].offsetHeight;
				}
			}

			var p = t.offset();
			item.left = p.left;
			item.top = p.top;
		};

		if(this.options.custom && this.options.custom.refreshContainers) {
			this.options.custom.refreshContainers.call(this);
		} else {
			for (var i = this.containers.length - 1; i >= 0; i--){
				var p = this.containers[i].element.offset();
				this.containers[i].containerCache.left = p.left;
				this.containers[i].containerCache.top = p.top;
				this.containers[i].containerCache.width	= this.containers[i].element.outerWidth();
				this.containers[i].containerCache.height = this.containers[i].element.outerHeight();
			};
		}

	},

	_createPlaceholder: function(that) {

		var self = that || this, o = self.options;

		if(!o.placeholder || o.placeholder.constructor == String) {
			var className = o.placeholder;
			o.placeholder = {
				element: function() {

					var el = $(document.createElement(self.currentItem[0].nodeName))
						.addClass(className || self.currentItem[0].className+" ui-sortable-placeholder")
						.removeClass('ui-sortable-helper')[0];

					if(!className) {
						el.style.visibility = "hidden";
						document.body.appendChild(el);
						el.innerHTML = self.currentItem[0].innerHTML.replace(/name\=\"[^\"\']+\"/g, ''); //Name attributes are removed, otherwice causes elements to be unchecked
						document.body.removeChild(el);
					};

					return el;
				},
				update: function(container, p) {
					if(className && !o.forcePlaceholderSize) return;
					if(!p.height()) { p.height(self.currentItem.innerHeight() - parseInt(self.currentItem.css('paddingTop')||0, 10) - parseInt(self.currentItem.css('paddingBottom')||0, 10)); };
					if(!p.width()) { p.width(self.currentItem.innerWidth() - parseInt(self.currentItem.css('paddingLeft')||0, 10) - parseInt(self.currentItem.css('paddingRight')||0, 10)); };
				}
			};
		}

		//Create the placeholder
		self.placeholder = $(o.placeholder.element.call(self.element, self.currentItem));

		//Append it after the actual current item
		self.currentItem.after(self.placeholder);

		//Update the size of the placeholder (TODO: Logic to fuzzy, see line 316/317)
		o.placeholder.update(self, self.placeholder);

	},

	_contactContainers: function(event) {
		for (var i = this.containers.length - 1; i >= 0; i--){

			if(this._intersectsWith(this.containers[i].containerCache)) {
				if(!this.containers[i].containerCache.over) {

					if(this.currentContainer != this.containers[i]) {

						//When entering a new container, we will find the item with the least distance and append our item near it
						var dist = 10000; var itemWithLeastDistance = null; var base = this.positionAbs[this.containers[i].floating ? 'left' : 'top'];
						for (var j = this.items.length - 1; j >= 0; j--) {
							if(!$.ui.contains(this.containers[i].element[0], this.items[j].item[0])) continue;
							var cur = this.items[j][this.containers[i].floating ? 'left' : 'top'];
							if(Math.abs(cur - base) < dist) {
								dist = Math.abs(cur - base); itemWithLeastDistance = this.items[j];
							}
						}

						if(!itemWithLeastDistance && !this.options.dropOnEmpty) //Check if dropOnEmpty is enabled
							continue;

						this.currentContainer = this.containers[i];
						itemWithLeastDistance ? this.options.sortIndicator.call(this, event, itemWithLeastDistance, null, true) : this.options.sortIndicator.call(this, event, null, this.containers[i].element, true);
						this._propagate("change", event); //Call plugins and callbacks
						this.containers[i]._propagate("change", event, this); //Call plugins and callbacks

						//Update the placeholder
						this.options.placeholder.update(this.currentContainer, this.placeholder);

					}

					this.containers[i]._propagate("over", event, this);
					this.containers[i].containerCache.over = 1;
				}
			} else {
				if(this.containers[i].containerCache.over) {
					this.containers[i]._propagate("out", event, this);
					this.containers[i].containerCache.over = 0;
				}
			}

		};
	},

	createHelper: function(event) {

		var o = this.options;
		var helper = typeof o.helper == 'function' ? $(o.helper.apply(this.element[0], [event, this.currentItem])) : (o.helper == "original" ? this.currentItem :  this.currentItem.clone());

		if (!helper.parents('body').length)
			$(o.appendTo != 'parent' ? o.appendTo : this.currentItem[0].parentNode)[0].appendChild(helper[0]); //Add the helper to the DOM if that didn't happen already

		return helper;

	},

	_convertPositionTo: function(d, pos) {
		if(!pos) pos = this.position;
		var mod = d == "absolute" ? 1 : -1;
		return {
			top: (
				pos.top																	// the calculated relative position
				+ this.offset.parent.top * mod											// The offsetParent's offset without borders (offset + border)
				- (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollTop) * mod	// The offsetParent's scroll position
				+ this.margins.top * mod												//Add the margin (you don't want the margin counting in intersection methods)
			),
			left: (
				pos.left																// the calculated relative position
				+ this.offset.parent.left * mod											// The offsetParent's offset without borders (offset + border)
				- (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollLeft) * mod	// The offsetParent's scroll position
				+ this.margins.left * mod												//Add the margin (you don't want the margin counting in intersection methods)
			)
		};
	},

	_generatePosition: function(event) {

		var o = this.options;
		var position = {
			top: (
				event.pageY																	// The absolute mouse position
				- this.offset.click.top													// Click offset (relative to the element)
				- this.offset.parent.top												// The offsetParent's offset without borders (offset + border)
				+ (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollTop)	// The offsetParent's scroll position, not if the element is fixed
			),
			left: (
				event.pageX																	// The absolute mouse position
				- this.offset.click.left												// Click offset (relative to the element)
				- this.offset.parent.left												// The offsetParent's offset without borders (offset + border)
				+ (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollLeft)	// The offsetParent's scroll position, not if the element is fixed
			)
		};

		if(!this.originalPosition) return position;										//If we are not dragging yet, we won't check for options

		/*
		 * - Position constraining -
		 * Constrain the position to a mix of grid, containment.
		 */
		if(this.containment) {
			if(position.left < this.containment[0]) position.left = this.containment[0];
			if(position.top < this.containment[1]) position.top = this.containment[1];
			if(position.left > this.containment[2]) position.left = this.containment[2];
			if(position.top > this.containment[3]) position.top = this.containment[3];
		}

		if(o.grid) {
			var top = this.originalPosition.top + Math.round((position.top - this.originalPosition.top) / o.grid[1]) * o.grid[1];
			position.top = this.containment ? (!(top < this.containment[1] || top > this.containment[3]) ? top : (!(top < this.containment[1]) ? top - o.grid[1] : top + o.grid[1])) : top;

			var left = this.originalPosition.left + Math.round((position.left - this.originalPosition.left) / o.grid[0]) * o.grid[0];
			position.left = this.containment ? (!(left < this.containment[0] || left > this.containment[2]) ? left : (!(left < this.containment[0]) ? left - o.grid[0] : left + o.grid[0])) : left;
		}

		return position;
	},

	_rearrange: function(event, i, a, hardRefresh) {

		a ? a[0].appendChild(this.placeholder[0]) : i.item[0].parentNode.insertBefore(this.placeholder[0], (this.direction == 'down' ? i.item[0] : i.item[0].nextSibling));

		//Various things done here to improve the performance:
		// 1. we create a setTimeout, that calls refreshPositions
		// 2. on the instance, we have a counter variable, that get's higher after every append
		// 3. on the local scope, we copy the counter variable, and check in the timeout, if it's still the same
		// 4. this lets only the last addition to the timeout stack through
		this.counter = this.counter ? ++this.counter : 1;
		var self = this, counter = this.counter;

		window.setTimeout(function() {
			if(counter == self.counter) self.refreshPositions(!hardRefresh); //Precompute after each DOM insertion, NOT on mousemove
		},0);

	},

	_clear: function(event, noPropagation) {

		this.reverting = false;

		//We first have to update the dom position of the actual currentItem
		if(!this._noFinalSort) this.placeholder.before(this.currentItem);
		this._noFinalSort = null;

		if(this.options.helper == "original")
			this.currentItem.css(this._storedCSS).removeClass("ui-sortable-helper");
		else
			this.currentItem.show();

		if(this.domPosition.prev != this.currentItem.prev().not(".ui-sortable-helper")[0] || this.domPosition.parent != this.currentItem.parent()[0]) this._propagate("update", event, null, noPropagation); //Trigger update callback if the DOM position has changed
		if(!$.ui.contains(this.element[0], this.currentItem[0])) { //Node was moved out of the current element
			this._propagate("remove", event, null, noPropagation);
			for (var i = this.containers.length - 1; i >= 0; i--){
				if($.ui.contains(this.containers[i].element[0], this.currentItem[0])) {
					this.containers[i]._propagate("update", event, this, noPropagation);
					this.containers[i]._propagate("receive", event, this, noPropagation);
				}
			};
		};

		//Post events to containers
		for (var i = this.containers.length - 1; i >= 0; i--){
			this.containers[i]._propagate("deactivate", event, this, noPropagation);
			if(this.containers[i].containerCache.over) {
				this.containers[i]._propagate("out", event, this);
				this.containers[i].containerCache.over = 0;
			}
		}

		this.dragging = false;
		if(this.cancelHelperRemoval) {
			this._propagate("beforeStop", event, null, noPropagation);
			this._propagate("stop", event, null, noPropagation);
			return false;
		}

		this._propagate("beforeStop", event, null, noPropagation);

		//$(this.placeholder[0]).remove(); would have been the jQuery way - unfortunately, it unbinds ALL events from the original node!
		this.placeholder[0].parentNode.removeChild(this.placeholder[0]);

		if(this.options.helper != "original") this.helper.remove(); this.helper = null;
		this._propagate("stop", event, null, noPropagation);

		return true;

	},

	_propagate: function(n, event, inst, noPropagation) {
		$.ui.plugin.call(this, n, [event, this._ui(inst)]);
		var dontCancel = !noPropagation ? this.element.triggerHandler(n == "sort" ? n : "sort"+n, [event, this._ui(inst)], this.options[n]) : true;
		if(dontCancel === false) this.cancel();
	},

	plugins: {},

	_ui: function(inst) {
		var self = inst || this;
		return {
			helper: self.helper,
			placeholder: self.placeholder || $([]),
			position: self.position,
			absolutePosition: self.positionAbs,
			item: self.currentItem,
			sender: inst ? inst.element : null
		};
	}

}));

$.extend($.ui.sortable, {
	getter: "serialize toArray",
	version: "@VERSION",
	defaults: {
		accurate: false,
		appendTo: "parent",
		cancel: ":input",
		delay: 0,
		distance: 1,
		dropOnEmpty: true,
		forcePlaceholderSize: false,
		helper: "original",
		items: '> *',
		scope: "default",
		scroll: true,
		scrollSensitivity: 20,
		scrollSpeed: 20,
		sortIndicator: $.ui.sortable.prototype._rearrange,
		tolerance: "guess",
		zIndex: 1000
	}
});

/*
 * Sortable Extensions
 */

$.ui.plugin.add("sortable", "axis", {
	sort: function(event, ui) {
		var i = $(this).data('sortable'), o = i.options;
		if(o.axis == "y") i.position.left = i.originalPosition.left;
		if(o.axis == "x") i.position.top = i.originalPosition.top;
	}
});

$.ui.plugin.add("sortable", "cursor", {
	start: function(event, ui) {
		var t = $('body'), i = $(this).data('sortable');
		if (t.css("cursor")) i.options._cursor = t.css("cursor");
		t.css("cursor", i.options.cursor);
	},
	beforeStop: function(event, ui) {
		var i = $(this).data('sortable');
		if (i.options._cursor) $('body').css("cursor", i.options._cursor);
	}
});

$.ui.plugin.add("sortable", "opacity", {
	start: function(event, ui) {
		var t = ui.helper, i = $(this).data('sortable');
		if(t.css("opacity")) i.options._opacity = t.css("opacity");
		t.css('opacity', i.options.opacity);
	},
	beforeStop: function(event, ui) {
		var i = $(this).data('sortable');
		if(i.options._opacity) $(ui.helper).css('opacity', i.options._opacity);
	}
});

$.ui.plugin.add("sortable", "scroll", {
	start: function(event, ui) {
		var i = $(this).data('sortable'), o = i.options;

		i.overflowY = function(el) {
			do { if(/auto|scroll/.test(el.css('overflow')) || (/auto|scroll/).test(el.css('overflow-y'))) return el; el = el.parent(); } while (el[0].parentNode);
			return $(document);
		}(i.currentItem);
		i.overflowX = function(el) {
			do { if(/auto|scroll/.test(el.css('overflow')) || (/auto|scroll/).test(el.css('overflow-x'))) return el; el = el.parent(); } while (el[0].parentNode);
			return $(document);
		}(i.currentItem);

		if(i.overflowY[0] != document && i.overflowY[0].tagName != 'HTML') i.overflowYOffset = i.overflowY.offset();
		if(i.overflowX[0] != document && i.overflowX[0].tagName != 'HTML') i.overflowXOffset = i.overflowX.offset();

	},
	sort: function(event, ui) {

		var i = $(this).data('sortable'), o = i.options;

		if(i.overflowY[0] != document && i.overflowY[0].tagName != 'HTML') {
			if((i.overflowYOffset.top + i.overflowY[0].offsetHeight) - event.pageY < o.scrollSensitivity)
				i.overflowY[0].scrollTop = i.overflowY[0].scrollTop + o.scrollSpeed;
			if(event.pageY - i.overflowYOffset.top < o.scrollSensitivity)
				i.overflowY[0].scrollTop = i.overflowY[0].scrollTop - o.scrollSpeed;
		} else {
			if(event.pageY - $(document).scrollTop() < o.scrollSensitivity)
				$(document).scrollTop($(document).scrollTop() - o.scrollSpeed);
			if($(window).height() - (event.pageY - $(document).scrollTop()) < o.scrollSensitivity)
				$(document).scrollTop($(document).scrollTop() + o.scrollSpeed);
		}

		if(i.overflowX[0] != document && i.overflowX[0].tagName != 'HTML') {
			if((i.overflowXOffset.left + i.overflowX[0].offsetWidth) - event.pageX < o.scrollSensitivity)
				i.overflowX[0].scrollLeft = i.overflowX[0].scrollLeft + o.scrollSpeed;
			if(event.pageX - i.overflowXOffset.left < o.scrollSensitivity)
				i.overflowX[0].scrollLeft = i.overflowX[0].scrollLeft - o.scrollSpeed;
		} else {
			if(event.pageX - $(document).scrollLeft() < o.scrollSensitivity)
				$(document).scrollLeft($(document).scrollLeft() - o.scrollSpeed);
			if($(window).width() - (event.pageX - $(document).scrollLeft()) < o.scrollSensitivity)
				$(document).scrollLeft($(document).scrollLeft() + o.scrollSpeed);
		}

	}
});

$.ui.plugin.add("sortable", "zIndex", {
	start: function(event, ui) {
		var t = ui.helper, i = $(this).data('sortable');
		if(t.css("zIndex")) i.options._zIndex = t.css("zIndex");
		t.css('zIndex', i.options.zIndex);
	},
	beforeStop: function(event, ui) {
		var i = $(this).data('sortable');
		if(i.options._zIndex) $(ui.helper).css('zIndex', i.options._zIndex);
	}
});

})(jQuery);