/*
 * jQuery UI Nested Sortable 1.2.1
 *
 * Copyright 2010, Manuele J Sarfatti
 *
 * http://mjsarfatti.com/sandbox/nestedSortable
 *
 * Depends:
 *	 jquery.ui.core.js 1.8+
 *	 jquery.ui.widget.js 1.8+
 *	 jquery.ui.sortable.js 1.8+
 */
(function($) {

	$.widget("ui.nestedSortable", $.extend({}, $.ui.sortable.prototype, {

		options: {
			tabSize: 20,
			disableNesting: 'ui-nestedSortable-no-nesting',
			errorClass: 'ui-nestedSortable-error',
			listType: 'ul'
		},

		_create: function(){
			this.element.data('sortable', this.element.data('sortableTree'));
			return $.ui.sortable.prototype._create.apply(this, arguments);
		},

		_mouseDrag: function(event) {

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

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

			//Do scrolling
			if(this.options.scroll) {
				var o = this.options, scrolled = false;
				if(this.scrollParent[0] != document && this.scrollParent[0].tagName != 'HTML') {

					if((this.overflowOffset.top + this.scrollParent[0].offsetHeight) - event.pageY < o.scrollSensitivity)
						this.scrollParent[0].scrollTop = scrolled = this.scrollParent[0].scrollTop + o.scrollSpeed;
					else if(event.pageY - this.overflowOffset.top < o.scrollSensitivity)
						this.scrollParent[0].scrollTop = scrolled = this.scrollParent[0].scrollTop - o.scrollSpeed;

					if((this.overflowOffset.left + this.scrollParent[0].offsetWidth) - event.pageX < o.scrollSensitivity)
						this.scrollParent[0].scrollLeft = scrolled = this.scrollParent[0].scrollLeft + o.scrollSpeed;
					else if(event.pageX - this.overflowOffset.left < o.scrollSensitivity)
						this.scrollParent[0].scrollLeft = scrolled = this.scrollParent[0].scrollLeft - o.scrollSpeed;

				} else {

					if(event.pageY - $(document).scrollTop() < o.scrollSensitivity)
						scrolled = $(document).scrollTop($(document).scrollTop() - o.scrollSpeed);
					else if($(window).height() - (event.pageY - $(document).scrollTop()) < o.scrollSensitivity)
						scrolled = $(document).scrollTop($(document).scrollTop() + o.scrollSpeed);

					if(event.pageX - $(document).scrollLeft() < o.scrollSensitivity)
						scrolled = $(document).scrollLeft($(document).scrollLeft() - o.scrollSpeed);
					else if($(window).width() - (event.pageX - $(document).scrollLeft()) < o.scrollSensitivity)
						scrolled = $(document).scrollLeft($(document).scrollLeft() + o.scrollSpeed);

				}

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

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

			//Set the helper position
			if(!this.options.axis || this.options.axis != "y") this.helper[0].style.left = this.position.left+'px';
			if(!this.options.axis || this.options.axis != "x") this.helper[0].style.top = this.position.top+'px';

			//Rearrange
			for (var i = this.items.length - 1; i >= 0; i--) {

				//Cache variables and intersection, continue if no intersection
				var item = this.items[i], itemElement = item.item[0], intersection = this._intersectsWithPointer(item);
				if (!intersection) continue;

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

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

					if (this.options.tolerance == "pointer" || this._intersectsWithSides(item)) {
						this._rearrange(event, item);
					} else {
						break;
					}

					// Clear emtpy ul's/ol's
					this._clearEmpty(itemElement);

					this._trigger("change", event, this._uiHash());
					break;
				}
			}

			// Get the real previous item
			itemBefore = this.placeholder[0].previousSibling;
			while (itemBefore != null) {
				if (itemBefore.nodeType == 1 && itemBefore != this.currentItem[0]) {
					break;
				} else {
					itemBefore = itemBefore.previousSibling;
				}
			}

			parentItem = this.placeholder[0].parentNode.parentNode;
			newList = document.createElement(o.listType);

			// Make/delete nested ul's/ol's
			if (parentItem != null && parentItem.nodeName == 'LI' && this.positionAbs.left < $(parentItem).offset().left) {
				$(parentItem).after(this.placeholder[0]);
				this._clearEmpty(parentItem);
			} else if (itemBefore != null && itemBefore.nodeName == 'LI' && this.positionAbs.left > $(itemBefore).offset().left + this.options.tabSize) {
				if (!($(itemBefore).hasClass(this.options.disableNesting))) {
					if ($(this.placeholder[0]).hasClass(this.options.errorClass)) {
						$(this.placeholder[0]).css('marginLeft', 0).removeClass(this.options.errorClass);
					}
					if (itemBefore.children[1] == null) {
						itemBefore.appendChild(newList);
					}
					itemBefore.children[1].appendChild(this.placeholder[0]);
				} else {
					$(this.placeholder[0]).addClass(this.options.errorClass).css('marginLeft', this.options.tabSize);
				}
			} else if (itemBefore != null) {
				if ($(this.placeholder[0]).hasClass(this.options.errorClass)) {
					$(this.placeholder[0]).css('marginLeft', 0).removeClass(this.options.errorClass);
				}
				$(itemBefore).after(this.placeholder[0]);
			} else {
				if ($(this.placeholder[0]).hasClass(this.options.errorClass)) {
					$(this.placeholder[0]).css('marginLeft', 0).removeClass(this.options.errorClass);
				}
			}

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

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

			//Call callbacks
			this._trigger('sort', event, this._uiHash());

			this.lastPositionAbs = this.positionAbs;
			return false;

		},

		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 || (/(.+)[-=_](.+)/));
				var pid = ($(o.item || this).parent(o.listType).parent('li').attr(o.attribute || 'id') || '').match(o.expression || (/(.+)[-=_](.+)/));
				if(res) str.push((o.key || res[1]+'['+(o.key && o.expression ? res[1] : res[2])+']')+'='+(pid ? (o.key && o.expression ? pid[1] : pid[2]) : 'root'));
			});

			if(!str.length && o.key) {
				str.push(o.key + '=');
			}

			return str.join('&');

		},

		toArray: function(o) {

			o = o || {};
			var sDepth = o.startDepthCount || 0;
			var ret = [];
			var left = 2;

			ret.push({"item_id": 'root', "parent_id": 'none', "depth": sDepth, "left": '1', "right": ($('li', this.element).length + 1) * 2});

			$(this.element).children('li').each(function() {
				left = _recursiveArray($(this), sDepth + 1, left);
			});

			return ret;

			function _recursiveArray(item, depth, left) {

				right = left + 1;

				if ($(item).children(o.listType).children('li').length > 0) {
					depth ++;
					$(item).children(o.listType).children('li').each(function() {
						right = _recursiveArray($(this), depth, right);
					});
					depth --;
				}

				id = $(item).attr('id').match(o.expression || (/(.+)[-=_](.+)/));

				if (depth === sDepth + 1) pid = 'root';
				else {
					parentItem = $(item).parent(o.listType).parent('li').attr('id').match(o.expression || (/(.+)[-=_](.+)/));
					pid = parentItem[2];
				}

				ret.push({"item_id": id[2], "parent_id": pid, "depth": depth, "left": left, "right": right});

				return left = right + 1;
			}

		},

		_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";

						return el;
					},
					update: function(container, p) {

						// 1. If a className is set as 'placeholder option, we don't force sizes - the class is responsible for that
						// 2. The option 'forcePlaceholderSize can be enabled to force it even if a class name is specified
						if(className && !o.forcePlaceholderSize) return;

						//If the element doesn't have an actual height by itself (without styles coming from a stylesheet), it receives the inline height from the dragged item
						if(!p.height() || p.css('height') == 'auto') { p.height(self.currentItem.height()); };
						if(!p.width()) { p.width(self.currentItem.width()); };
					}
				};
			}

			//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);

		},

		_clear: function(event, noPropagation) {

			$.ui.sortable.prototype._clear.apply(this, arguments);

			// Clean last empty ul/ol
			for (var i = this.items.length - 1; i >= 0; i--) {
				var item = this.items[i].item[0];
				this._clearEmpty(item);
			}
			return true;

		},

		_clearEmpty: function(item) {

			if (item.children[1] && item.children[1].children.length == 0) {
				item.removeChild(item.children[1]);
			}

		}

	}));

	$.ui.nestedSortable.prototype.options = $.extend({}, $.ui.sortable.prototype.options, $.ui.nestedSortable.prototype.options);

})(jQuery);