/*
 * jQuery SmoothDivScroll 1.0
 *
 * Copyright (c) 2010 Thomas Kahn
 * Licensed under the GPL license.
 *
 * http://www.maaki.com/thomas/SmoothDivScroll/
 *
 * Depends:
 * jquery.ui.widget.js
 *
 */
(function($) {

	$.widget("thomaskahn.smoothDivScroll", {
		// Default options
		options: {
			scrollingHotSpotLeft: "div.scrollingHotSpotLeft", 
			scrollingHotSpotRight: "div.scrollingHotSpotRight", 
			scrollableArea : "div.scrollableArea",
			scrollWrapper: "div.scrollWrapper", 
			hiddenOnStart: false, 
			ajaxContentURL: "",
			countOnlyClass: "",
			scrollStep: 15,
			scrollInterval: 10,
			mouseDownSpeedBooster: 3, 
			autoScroll: "", 
			autoScrollDirection: "right", 
			autoScrollStep: 5,
			autoScrollInterval: 10,
			visibleHotSpots: "",
			hotSpotsVisibleTime: 5, 
			startAtElementId: ""
		},
		_create: function() {
		
			// Set variables
			var self = this, o = this.options, el = this.element;
			
			el.data("scrollWrapper", el.find(o.scrollWrapper));
			el.data("scrollingHotSpotRight", el.find(o.scrollingHotSpotRight));
			el.data("scrollingHotSpotLeft", el.find(o.scrollingHotSpotLeft));
			el.data("scrollableArea", el.find(o.scrollableArea));
			el.data("speedBooster", 1);
			el.data("motherElementOffset", el.offset().left);
			el.data("scrollXPos", 0);
			el.data("hotSpotWidth", el.find(o.scrollingHotSpotLeft).width());
			el.data("scrollableAreaWidth", 0);
			el.data("startingPosition", 0);
			el.data("rightScrollInterval", null);
			el.data("leftScrollInterval", null);
			el.data("autoScrollInterval", null);
			el.data("hideHotSpotBackgroundsInterval", null);
			el.data("previousScrollLeft", 0);
			el.data("pingPongDirection", "right");
			el.data("getNextElementWidth", true);
			el.data("swapAt", null);
			el.data("startAtElementHasNotPassed", true);
			el.data("swappedElement", null);
			el.data("originalElements", el.data("scrollableArea").children(o.countOnlyClass));
			el.data("visible",true);

			self.recalculateScrollableArea();

			// Set the starting position of the scrollable area. 
			// If no startAtElementId is set, the starting position
			// will be the default value (zero)
			el.data("scrollWrapper").scrollLeft(el.data("startingPosition"));

			// If the user wants to have visible hotspots, here is where it's taken care of
			if(o.autoScroll !== "always") {
				switch(o.visibleHotSpots)
				{
					case "always":
						self.showHotSpotBackgrounds();
						break;
					case "onstart":
						self.showHotSpotBackgrounds();
						el.data("hideHotSpotBackgroundsInterval", setTimeout(function(){
							self.hideHotSpotBackgrounds("slow");
						},(o.hotSpotsVisibleTime * 1000)));
						break;
					default:
						break;
				}
			}
			/*****************************************
			 SET UP EVENTS FOR SCROLLING RIGHT
			*****************************************/
			// Check the mouse X position and calculate the relative X position inside the right hotspot
			el.data("scrollingHotSpotRight").bind("mousemove", function(e){
				var x = e.pageX - (this.offsetLeft + el.data("motherElementOffset"));
				el.data("scrollXPos", Math.round((x/el.data("hotSpotWidth")) * o.scrollStep));
				if(el.data("scrollXPos") === Infinity) { 
					el.data("scrollXPos", 0);
				}
			});	

			// mouseover right hotspot - scrolling
			el.data("scrollingHotSpotRight").bind("mouseover", function(){	
				
				// Clear autoscrolling, if it should only run on start
				if((o.autoScroll === "onstart" && el.data("autoScrollInterval") !== null)) 
				{
					clearInterval(el.data("autoScrollInterval"));
					el.data("autoScrollInterval", null);
					self._trigger("autoScrollIntervalStopped");
				}

				// Start the scrolling interval
				el.data("rightScrollInterval", setInterval(function(){
				
					if(el.data("scrollXPos") > 0)
					{
						el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() + (el.data("scrollXPos") * el.data("speedBooster")));
						
						self._showHideHotSpots();
					}
	
				}, o.scrollInterval));
				
				// Callback
				self._trigger("mouseOverRightHotSpot");
				
			});
			
			// mouseout right hotspot
			el.data("scrollingHotSpotRight").bind("mouseout", function(){
				clearInterval(el.data("rightScrollInterval"));
				el.data("scrollXPos", 0);
			});
			
			// mousedown right hotspot (add scrolling speed booster)
			el.data("scrollingHotSpotRight").bind("mousedown", function(){
				el.data("speedBooster", o.mouseDownSpeedBooster);
			});
			
			// mouseup anywhere (stop boosting the scrolling speed)
			$("body").bind("mouseup", function(){
				el.data("speedBooster", 1);
			});
		
			/*****************************************
			 SET UP EVENTS FOR SCROLLING LEFT
			*****************************************/
			// Check the mouse X position and calculate the relative X position inside the left hotspot
			el.data("scrollingHotSpotLeft").bind("mousemove", function(e){
				var x = el.data("scrollingHotSpotLeft").innerWidth() - (e.pageX - el.data("motherElementOffset"));
				el.data("scrollXPos", Math.round((x/el.data("hotSpotWidth")) * o.scrollStep));
				if(el.data("scrollXPos") === Infinity) { 
					el.data("scrollXPos", 0);
				}
				
			});

			// mouseover left hotspot
			el.data("scrollingHotSpotLeft").bind("mouseover", function(){
				
				// Clear autoscrolling, if it should only run on start

				if((o.autoScroll === "onstart" && el.data("autoScrollInterval") !== null)) 
				{
					clearInterval(el.data("autoScrollInterval"));
					el.data("autoScrollInterval", null);
					self._trigger("autoScrollIntervalStopped");
				}
				
				el.data("leftScrollInterval", setInterval(function(){
					if(el.data("scrollXPos") > 0) {
						el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() - (el.data("scrollXPos")*el.data("speedBooster")));
						
						self._showHideHotSpots();
					}
					
				}, o.scrollInterval));
				
				// Callback
				self._trigger("mouseOverLeftHotSpot");
			});
			
			// mouseout left hotspot
			el.data("scrollingHotSpotLeft").bind("mouseout", function(){
				clearInterval(el.data("leftScrollInterval"));
				el.data("scrollXPos", 0);
			});

			// mousedown left hotspot (add scrolling speed booster)
			el.data("scrollingHotSpotLeft").bind("mousedown", function(){
				el.data("speedBooster", o.mouseDownSpeedBooster);
			});
			
			/*****************************************
			 SET UP EVENT FOR RESIZING THE BROWSER WINDOW
			*****************************************/
			$(window).bind("resize", function(){
				// If the scrollable area is not hidden on start, show/hide the hotspots
				if(!(o.hiddenOnStart)) { 
					self._showHideHotSpots();
				}
				
				self._trigger("windowResized");
			});
			
			/*****************************************
			 AUTOSCROLLING
			*****************************************/
			// If the user has set the option autoScroll, the scollable area will
			// start scrolling automatically
			if(o.autoScroll !== "" && !(o.hiddenOnStart)) {
				self.startAutoScroll();
			}
			
			// Should it be hidden on start?
			if(o.hiddenOnStart) { 
				self.hide();
			}
	
		},
		/**********************************************************
		 Hotspot functions
		**********************************************************/
		showHotSpotBackgrounds: function(fadeSpeed)
		{
			// Alter the CSS (SmoothDivScroll.css) if you want to customize
			// the look'n'feel of the visible hotspots
			var self = this, el = this.element;
			
			// Fade in the hotspot backgrounds
			if(fadeSpeed !== undefined)
			{	
				// Before the fade-in starts, we need to make sure the opacity
				// is zero
				el.data("scrollingHotSpotLeft").css("opacity","0.0");
				el.data("scrollingHotSpotRight").css("opacity","0.0");
				
				el.data("scrollingHotSpotLeft").addClass("scrollingHotSpotLeftVisible");
				el.data("scrollingHotSpotRight").addClass("scrollingHotSpotRightVisible");
				
				// Fade in the left hotspot
				el.data("scrollingHotSpotLeft").fadeTo(fadeSpeed, 0.35);

				// Fade in the right hotspot
				el.data("scrollingHotSpotRight").fadeTo(fadeSpeed, 0.35);
			}
			// Don't fade, just show them
			else
			{
				// The left hotspot
				el.data("scrollingHotSpotLeft").addClass("scrollingHotSpotLeftVisible");
				el.data("scrollingHotSpotLeft").removeAttr("style");
				
				// The right hotspot
				el.data("scrollingHotSpotRight").addClass("scrollingHotSpotRightVisible");
				el.data("scrollingHotSpotRight").removeAttr("style");
			}
			self._showHideHotSpots();
		},
		hideHotSpotBackgrounds: function(fadeSpeed)
		{
			var el = this.element;
			
			// Fade out the hotspot backgrounds
			if(fadeSpeed !== undefined)
			{	
				// Fade out the left hotspot
				el.data("scrollingHotSpotLeft").fadeTo(fadeSpeed, 0.0, function(){
					el.data("scrollingHotSpotLeft").removeClass("scrollingHotSpotLeftVisible");
				});

				// Fade out the right hotspot
				el.data("scrollingHotSpotRight").fadeTo(fadeSpeed, 0.0,function(){
					el.data("scrollingHotSpotRight").removeClass("scrollingHotSpotRightVisible");
				});
			}
			// Don't fade, just hide them
			else
			{
				el.data("scrollingHotSpotLeft").removeClass("scrollingHotSpotLeftVisible");
				el.data("scrollingHotSpotLeft").removeAttr("style");
				
				el.data("scrollingHotSpotRight").removeClass("scrollingHotSpotRightVisible");
				el.data("scrollingHotSpotRight").removeAttr("style");
			}
			
		},
		// Function for showing and hiding hotspots depending on the
		// offset of the scrolling
		_showHideHotSpots: function()
		{
			var self = this, el = this.element, o = this.options;
			
			// If autoscrolling is set to always, there should be no hotspots
			if(o.autoScroll !== "always")
			{
				// If the scrollable area is shorter than the scroll wrapper, both hotspots
				// should be hidden
				if(el.data("scrollableAreaWidth") <= (el.data("scrollWrapper").innerWidth()))
				{
					el.data("scrollingHotSpotLeft").hide();
					el.data("scrollingHotSpotRight").hide();
				}
				// When you can't scroll further left the left scroll hotspot should be hidden
				// and the right hotspot visible.
				else if (el.data("scrollWrapper").scrollLeft() === 0)
				{
					el.data("scrollingHotSpotLeft").hide();
					el.data("scrollingHotSpotRight").show();
					// Callback
					self._trigger("scrollLeftLimitReached");
					// Clear interval
					clearInterval(el.data("leftScrollInterval"));
					el.data("leftScrollInterval", null);
				}
				// When you can't scroll further right
				// the right scroll hotspot should be hidden
				// and the left hotspot visible
				else if (el.data("scrollableAreaWidth") <= (el.data("scrollWrapper").innerWidth() + el.data("scrollWrapper").scrollLeft()))
				{
					el.data("scrollingHotSpotLeft").show();
					el.data("scrollingHotSpotRight").hide();
					// Callback
					self._trigger("scrollRightLimitReached");
					// Clear interval
					clearInterval(el.data("rightScrollInterval"));
					el.data("rightScrollInterval", null);
				}
				// If you are somewhere in the middle of your
				// scrolling, both hotspots should be visible
				else
				{
					el.data("scrollingHotSpotLeft").show();
					el.data("scrollingHotSpotRight").show();
				}
			}
			else
			{
				el.data("scrollingHotSpotLeft").hide();
				el.data("scrollingHotSpotRight").hide();
			}
		},
		/**********************************************************
		 Moving to a certain element
		**********************************************************/
		moveToElement: function(moveTo, elementNumber) {
			var self = this, el = this.element, o = this.options, tempScrollableAreaWidth = 0, foundStartAtElement = false;
			
			switch(moveTo)
			{
				case "first":
					el.data("scrollXPos", 0);
					self._trigger("movedToFirstElement");
					break;
				case "start":
					// Check to see where the start-at element is at the moment.
					// This can vary if endlessloop is used for autoscroll since it
					// swaps elements around.
					
					el.data("scrollableArea").children(o.countOnlyClass).each(function() {
						
						if( (o.startAtElementId.length !== 0) && (($(this).attr("id")) === o.startAtElementId) ) 
						{
							el.data("startingPosition", tempScrollableAreaWidth);
							foundStartAtElement = true;
						}
						tempScrollableAreaWidth = tempScrollableAreaWidth + $(this).outerWidth(true);
					});
					
					el.data("scrollXPos", el.data("startingPosition"));
					self._trigger("movedToStartElement");
					break;
				case "last":
					el.data("scrollXPos", el.data("scrollableAreaWidth"));
					self._trigger("movedToLastElement");
					break;
				case "number":
					if(!(isNaN(elementNumber))) {
						// Get the total width of all preceding elements					
						el.data("scrollableArea").children(o.countOnlyClass).each(function(index) {
							if(index === (elementNumber-1)) 
							{
								el.data("scrollXPos", tempScrollableAreaWidth);
							}
							tempScrollableAreaWidth = tempScrollableAreaWidth + $(this).outerWidth(true);
						});
					}
					self._trigger("movedToElementNumber", null, {"elementNumber": elementNumber});
					break;
				default:
					break;
			}
			
			el.data("scrollWrapper").scrollLeft(el.data("scrollXPos"));
			self._showHideHotSpots();
		},
		/**********************************************************
		 Adding or replacing content
		**********************************************************/
		addContent: function(ajaxContentURL, addWhere)
		{
			var self = this, el = this.element;

			$.get(ajaxContentURL, function(data){
				// Add the loaded content first or last in the scrollable area
				if(addWhere === "first") {
					el.data("scrollableArea").children(":first").before(data);
				}
				else {
					el.data("scrollableArea").children(":last").after(data);
				}
				
				// Recalculate the total width of the elements inside the scrollable area
				self.recalculateScrollableArea();
				
				// Determine which hotspots to show
				self._showHideHotSpots();
			});
		},
		replaceContent: function(ajaxContentURL)
		{
			var self = this, el = this.element;
			
			el.data("scrollableArea").load(ajaxContentURL, function(){
				// Recalculate the total width of the elements inside the scrollable area
				self.recalculateScrollableArea();
				self.moveToElement("first");
				self._showHideHotSpots();
				el.data("startingPosition", 0);
			});
		},
		/**********************************************************
		 Recalculate the scrollable area
		**********************************************************/
		recalculateScrollableArea: function() {
			
			var tempScrollableAreaWidth = 0, foundStartAtElement = false, o = this.options, el = this.element;

			// Add up the total width of all the items inside the scrollable area
			el.data("scrollableArea").children(o.countOnlyClass).each(function() {
				// Check to see if the current element in the loop is the one where the scrolling should start
				if( (o.startAtElementId.length !== 0) && (($(this).attr("id")) === o.startAtElementId) ) 
				{
					el.data("startingPosition", tempScrollableAreaWidth);
					foundStartAtElement = true;
				}
				tempScrollableAreaWidth = tempScrollableAreaWidth + $(this).outerWidth(true);
			});

			// If the element with the ID specified by startAtElementId
			// is not found, reset it
			if (!(foundStartAtElement)) {
				el.data("startAtElementId", "");
			}
		
			// Set the width of the scrollable area
			el.data("scrollableAreaWidth", tempScrollableAreaWidth);
			el.data("scrollableArea").width(el.data("scrollableAreaWidth"));
		},
		/**********************************************************
		 Stopping, starting and doing the autoscrolling
		**********************************************************/
		stopAutoScroll: function() {
			var self = this, el = this.element;
			
			clearInterval(el.data("autoScrollInterval"));
			el.data("autoScrollInterval", null);
			
			// Check to see which hotspots should be active
			// in the position where the scroller has stopped
			self._showHideHotSpots();
					
			self._trigger("autoScrollStopped");
			
		},
		startAutoScroll: function() {
			var self = this, el = this.element, o = this.options;
			
			self._showHideHotSpots();
			
			// Stop any running interval
			clearInterval(el.data("autoScrollInterval"));
			el.data("autoScrollInterval", null);
			
			// Callback
			self._trigger("autoScrollStarted");
			
			// Start interval
			el.data("autoScrollInterval", setInterval(function(){
				
				// If the scroller is not visible or
				// if the scrollable area is shorter than the scroll wrapper
				// any running autoscroll interval should stop.
				if(!(el.data("visible")) || (el.data("scrollableAreaWidth") <= (el.data("scrollWrapper").innerWidth())))
				{				
					// Stop any running interval
					clearInterval(el.data("autoScrollInterval"));
					el.data("autoScrollInterval", null);
				}
				
				// Store the old scrollLeft value to see if the scrolling has reached the end
				el.data("previousScrollLeft", el.data("scrollWrapper").scrollLeft());
				
				switch(o.autoScrollDirection)
				{
				case "right":
					el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() + o.autoScrollStep);
					if(el.data("previousScrollLeft") === el.data("scrollWrapper").scrollLeft())
					{
						self._trigger("autoScrollRightLimitReached");
						clearInterval(el.data("autoScrollInterval"));
						el.data("autoScrollInterval", null);
						self._trigger("autoScrollIntervalStopped");
					}
					break;

				case "left":
					el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() - o.autoScrollStep);
					if(el.data("previousScrollLeft") === el.data("scrollWrapper").scrollLeft())
					{
						self._trigger("autoScrollLeftLimitReached");
						clearInterval(el.data("autoScrollInterval"));
						el.data("autoScrollInterval", null);
						self._trigger("autoScrollIntervalStopped");
					}
					break;
					
				case "backandforth":
					
					
					if(el.data("pingPongDirection") === "right") { 
						el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() + (o.autoScrollStep));
					}
					else {
						el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() - (o.autoScrollStep));
					}
					
					// If the scrollLeft hasnt't changed it means that the scrolling has reached
					// the end and the direction should be switched
					if(el.data("previousScrollLeft") === el.data("scrollWrapper").scrollLeft())
					{
						if(el.data("pingPongDirection") === "right") 
						{
							el.data("pingPongDirection", "left");
							self._trigger("autoScrollRightLimitReached");
						}
						else 
						{
							el.data("pingPongDirection", "right");
							self._trigger("autoScrollLeftLimitReached");
						}
					}
					break;

				case "endlessloopright":
					// Get the width of the first element. When it has scrolled out of view,
					// the element swapping should be executed. A true/false variable is used
					// as a flag variable so the swapAt value doesn't have to be recalculated
					// in each loop.

					if(el.data("getNextElementWidth"))
					{
						if((o.startAtElementId !== "") && (el.data("startAtElementHasNotPassed"))) {
							el.data("swapAt", $("#" + o.startAtElementId).outerWidth(true));
							el.data("startAtElementHasNotPassed", false);
						}
						else {
							el.data("swapAt", el.data("scrollableArea").children(":first").outerWidth(true));
						}
						
						el.data("getNextElementWidth", false);
					}
		
					// Do the autoscrolling
					el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() + o.autoScrollStep);

					// Check to see if the swap should be done
					if(el.data("swapAt") <= el.data("scrollWrapper").scrollLeft())
					{ 
						el.data("swappedElement", el.data("scrollableArea").children(":first").detach());
						el.data("scrollableArea").append(el.data("swappedElement"));
						el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() - el.data("swappedElement").outerWidth(true));
						el.data("getNextElementWidth", true);
					}
					break;
				case "endlessloopleft":
					// Get the width of the first element. When it has scrolled out of view,
					// the element swapping should be executed. A true/false variable is used
					// as a flag variable so the swapAt value doesn't have to be recalculated
					// in each loop.

					if(el.data("getNextElementWidth"))
					{
						if((o.startAtElementId !== "") && (el.data("startAtElementHasNotPassed"))) {
							el.data("swapAt", $("#" + o.startAtElementId).outerWidth(true));
							el.data("startAtElementHasNotPassed", false);
						}
						else {
							el.data("swapAt", el.data("scrollableArea").children(":first").outerWidth(true));
						}
		
						el.data("getNextElementWidth", false);
					}
		
					// Do the autoscrolling
					el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() - o.autoScrollStep);
					
					// Check to see if the swap should be done
					if(el.data("scrollWrapper").scrollLeft() === 0)
					{ 
						el.data("swappedElement", el.data("scrollableArea").children(":last").detach());
						el.data("scrollableArea").prepend(el.data("swappedElement"));
						el.data("scrollWrapper").scrollLeft(el.data("scrollWrapper").scrollLeft() + el.data("swappedElement").outerWidth(true));
						el.data("getNextElementWidth", true);
					}
					break;
				default:
					break;
					
				}
			}, o.autoScrollInterval));
		
		},
		restoreOriginalElements: function() {
			var self = this, el = this.element;
			
			// Restore the original content of the scrollable area
			el.data("scrollableArea").html(el.data("originalElements"));
			self.recalculateScrollableArea();
			self.moveToElement("first");
		},
		show: function(){
			var el = this.element;
			el.data("visible", true);
			el.show();
		},
		hide: function(){
			var el = this.element;
			el.data("visible", false);
			el.hide();
		},
		destroy: function() {
			var el = this.element;
			
			// Clear all running intervals
			clearInterval(el.data("autoScrollInterval"));
			clearInterval(el.data("rightScrollInterval"));
			clearInterval(el.data("leftScrollInterval"));
			clearInterval(el.data("hideHotSpotBackgroundsInterval"));
			
			// Remove all element specific events
			el.data("scrollingHotSpotRight").unbind("mouseover");
			el.data("scrollingHotSpotRight").unbind("mouseout");
			el.data("scrollingHotSpotRight").unbind("mousedown");
			
			el.data("scrollingHotSpotLeft").unbind("mouseover");
			el.data("scrollingHotSpotLeft").unbind("mouseout");	
			el.data("scrollingHotSpotLeft").unbind("mousedown");

			// Restore the original content of the scrollable area
			el.data("scrollableArea").html(el.data("originalElements"));
			// Remove the width of the scrollable area
			el.data("scrollableArea").removeAttr("style");
			el.data("scrollingHotSpotRight").removeAttr("style");
			el.data("scrollingHotSpotLeft").removeAttr("style");

			el.data("scrollWrapper").scrollLeft(0);
			el.data("scrollingHotSpotLeft").removeClass("scrollingHotSpotLeftVisible");
			el.data("scrollingHotSpotRight").removeClass("scrollingHotSpotRightVisible"); 
			el.data("scrollingHotSpotRight").hide();
			el.data("scrollingHotSpotLeft").hide();
			
			// Call the base destroy function
			$.Widget.prototype.destroy.apply(this, arguments);
			
		}
	});
})(jQuery);