/*
 * jQuery UI Swappable 0.9.5
 *
 * Copyright (c) 2010 Vadim Kiryukhin
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 *
 * Based on jquery.ui.sortable.js
 *
 * Depends:
 *		jquery.ui.core.js
 *		jquery.ui.mouse.js
 *		jquery.ui.widget.js
 *  	jquery.ui.sortable.js
 *
 * Usage:
 *
 *		Option's specific:
 *
 *		1. Always set option "cursorAt: {top: -nnn}" as a Negative Integer.
 *		2. Always set option "items" with items' class name, not element or filter.
 *
 *		Example:
 *			
 *			<ul id="foo">
 *				<li class="bar"><li>
 *				<li class="bar"><li>
 *				<li class="bar"><li>
 *			</ul>
 *			
 *			$("#foo").swappable({
 *				items:'.bar', // Mandatory option, class only.
 *				cursorAt: {top:-20}, // MUST be set to negative. Default doesn't work!
 *			});
 */
	 
	 
(function($) {

$.widget("ui.swappable", $.ui.sortable, {

	_mouseStart: function(event, overrideHandle, noActivation) {

		var o = this.options, self = this;
		o.helper = "original",

		this.currentContainer = this;

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

		//Cache the helper size
		this._cacheHelperProportions();

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

		//Cache the margins of the original element
		this._cacheMargins();

		//Get the next scrolling parent
		this.scrollParent = this.helper.scrollParent();

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

		// Only after we got the offset, we can change the helper's position to absolute
		// TODO: Still need to figure out a way to make relative sorting possible
		this.helper.css("position", "absolute");
		this.cssPosition = this.helper.css("position");

		$.extend(this.offset, {
			click: { //Where the click happened, relative to the element
				left: event.pageX - this.offset.left,
				top: event.pageY - this.offset.top
			},
			parent: this._getParentOffset(),
			relative: this._getRelativeOffset() //This is a relative to absolute position minus the actual position calculation - only used for relative positioned helper
		});

		//Generate the original position
		this.originalPosition = this._generatePosition(event);
		this.originalPageX = event.pageX;
		this.originalPageY = event.pageY;

		//Adjust the mouse offset relative to the helper if 'cursorAt' is supplied
		(o.cursorAt && this._adjustOffsetFromHelper(o.cursorAt));

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

		//If the helper is not the original, hide the original so it's not playing any role during the drag, won't cause anything bad this way
		if(this.helper[0] != this.currentItem[0]) {
			this.currentItem.hide();
		}

		//Create the placeholder
		this._createPlaceholder();

		//Set a containment if given in the options
		if(o.containment)
			this._setContainment();

		if(o.cursor) { // cursor option
			if ($('body').css("cursor")) this._storedCursor = $('body').css("cursor");
			$('body').css("cursor", o.cursor);
		}

		if(o.opacity) { // opacity option
			if (this.helper.css("opacity")) this._storedOpacity = this.helper.css("opacity");
			this.helper.css("opacity", o.opacity);
		}

		if(o.zIndex) { // zIndex option
			if (this.helper.css("zIndex")) this._storedZIndex = this.helper.css("zIndex");
			this.helper.css("zIndex", o.zIndex);
		}

		//Prepare scrolling
		if(this.scrollParent[0] != document && this.scrollParent[0].tagName != 'HTML')
			this.overflowOffset = this.scrollParent.offset();

		//Call callbacks
		this._trigger("start", event, this._uiHash());

		//Recache the helper size
		if(!this._preserveHelperProportions)
			this._cacheHelperProportions();


		//Post 'activate' events to possible containers
		if(!noActivation) {
			 for (var i = this.containers.length - 1; i >= 0; i--) { this.containers[i]._trigger("activate", event, self._uiHash(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.helper.addClass("ui-sortable-helper");
		this._mouseDrag(event); //Execute the drag once - this causes the helper not to be visible before getting its correct position
		return true;

	},
	_mouseStop: function(event, noPropagation) {

		if(!event) return;
		
		var o = this.options;
		var target = event.target;
		
		var itemPassive = $(target).closest(o.items);
		var itemActive = this.currentItem.closest(o.items);
		var itemPlaceholder = $(itemActive).next();
		
		$(itemPassive).after(itemActive);
		$(itemPlaceholder).after(itemPassive);
		
		//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;

	},
	
	_clear: function(event, noPropagation) {

		this.reverting = false;
		// We delay all events that have to be triggered to after the point where the placeholder has been removed and
		// everything else normalized again
		var delayedTriggers = [], self = this;

		this._noFinalSort = null;

		if(this.helper[0] == this.currentItem[0]) {
			
			for(var i in this._storedCSS) {
				if(this._storedCSS[i] == 'auto' || this._storedCSS[i] == 'static') this._storedCSS[i] = '';
			}
			this.currentItem.css(this._storedCSS).removeClass("ui-sortable-helper");
		} else {
			this.currentItem.show();
		}

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

		//Post events to containers
		for (var i = this.containers.length - 1; i >= 0; i--){
			if(!noPropagation) delayedTriggers.push((function(c) { return function(event) { c._trigger("deactivate", event, this._uiHash(this)); };  }).call(this, this.containers[i]));
			if(this.containers[i].containerCache.over) {
				delayedTriggers.push((function(c) { return function(event) { c._trigger("out", event, this._uiHash(this)); };  }).call(this, this.containers[i]));
				this.containers[i].containerCache.over = 0;
			}
		}

		//Do what was originally in plugins
		if(this._storedCursor) $('body').css("cursor", this._storedCursor); //Reset cursor
		if(this._storedOpacity) this.helper.css("opacity", this._storedOpacity); //Reset opacity
		if(this._storedZIndex) this.helper.css("zIndex", this._storedZIndex == 'auto' ? '' : this._storedZIndex); //Reset z-index

		this.dragging = false;
		if(this.cancelHelperRemoval) {
			if(!noPropagation) {
				this._trigger("beforeStop", event, this._uiHash());
				for (var i=0; i < delayedTriggers.length; i++) { delayedTriggers[i].call(this, event); }; //Trigger all delayed events
				this._trigger("stop", event, this._uiHash());
			}
			return false;
		}

		if(!noPropagation) this._trigger("beforeStop", event, this._uiHash());

		//$(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.helper[0] != this.currentItem[0]) this.helper.remove(); this.helper = null;

		if(!noPropagation) {
			for (var i=0; i < delayedTriggers.length; i++) { delayedTriggers[i].call(this, event); }; //Trigger all delayed events
			this._trigger("stop", event, this._uiHash());
		}

		this.fromOutside = false;
		return true;

	}
	
});

$.extend($.ui.swappable, {
	version: "0.9.5"
});

})(jQuery);