//Step Carousel Viewer: By Dynamic Drive, at http://www.dynamicdrive.com
//** Created: March 19th, 08'
//** Aug 16th, 08'- Updated to v 1.4:
	//1) Adds ability to set speed/duration of panel animation (in milliseconds)
	//2) Adds persistence support, so the last viewed panel is recalled when viewer returns within same browser session
	//3) Adds ability to specify whether panels should stop at the very last and first panel, or wrap around and start all over again
	//4) Adds option to specify two navigational image links positioned to the left and right of the Carousel Viewer to move the panels back and forth

//** Aug 27th, 08'- Nav buttons (if enabled) also repositions themselves now if window is resized

//** Sept 23rd, 08'- Updated to v 1.6:
	//1) Carousel now stops at the very last visible panel, instead of the last panel itself. In other words, no more white space at the end.
	//2) Adds ability for Carousel to auto rotate dictated by the new parameter: autostep: {enable:true, moveby:1, pause:3000}
	//2i) During Auto Rotate, Carousel pauses onMouseover, resumes onMouseout. Clicking Carousel halts auto rotate.

//** Oct 22nd, 08'- Updated to v 1.6.1, which fixes functions stepBy() and stepTo() not stopping auto stepping of Carousel when called.

var stepcarousel = {};
(function($) {
	stepcarousel = {
		ajaxloadingmsg: '<div style="margin: 1em; font-weight: bold"><img src="ajaxloadr.gif" style="vertical-align: middle" /> Fetching Content. Please wait...</div>', //customize HTML to show while fetching Ajax content
		defaultbuttonsfade: 0.4, //Fade degree for disabled nav buttons (0=completely transparent, 1=completely opaque)
		configholder: {},
	
		getCSSValue:function(val){ //Returns either 0 (if val contains 'auto') or val as an integer
			return (val=="auto")? 0 : parseInt(val)
		},
	
		getremotepanels:function($, config){ //function to fetch external page containing the panel DIVs
			config.$belt.html(this.ajaxloadingmsg)
			$.ajax({
				url: config.contenttype[1], //path to external content
				async: true,
				error:function(ajaxrequest){
					config.$belt.html('Error fetching content.<br />Server Response: '+ajaxrequest.responseText)
				},
				success:function(content){
					config.$belt.html(content)
					config.$panels=config.$gallery.find('.'+config.panelclass)
					stepcarousel.alignpanels($, config)
				}
			})
		},
	
		getoffset:function(what, offsettype){
			return (what.offsetParent)? what[offsettype]+this.getoffset(what.offsetParent, offsettype) : what[offsettype]
		},
	
		getCookie:function(Name){ 
			var re=new RegExp(Name+"=[^;]+", "i"); //construct RE to search for target name/value pair
			if (document.cookie.match(re)) //if cookie found
				return document.cookie.match(re)[0].split("=")[1] //return its value
			return null
		},
	
		setCookie:function(name, value){
			document.cookie = name+"="+value
		},
	
		fadebuttons:function(config, currentpanel){
			config.$leftnavbutton.fadeTo('fast', currentpanel==0? this.defaultbuttonsfade : 1)
			config.$rightnavbutton.fadeTo('fast', currentpanel==config.lastvisiblepanel? this.defaultbuttonsfade : 1)
		},
	
		addnavbuttons:function(config, currentpanel){
			// config.$leftnavbutton=$('<img src="'+config.defaultbuttons.leftnav[0]+'">').css({zIndex:50, position:'absolute', left:config.offsets.left+config.defaultbuttons.leftnav[1]+'px', top:config.offsets.top+config.defaultbuttons.leftnav[2]+'px', cursor:'hand', cursor:'pointer'}).attr({title:'Back '+config.defaultbuttons.moveby+' panels'}).appendTo('body')
			// config.$rightnavbutton=$('<img src="'+config.defaultbuttons.rightnav[0]+'">').css({zIndex:50, position:'absolute', left:config.offsets.left+config.$gallery.get(0).offsetWidth+config.defaultbuttons.rightnav[1]+'px', top:config.offsets.top+config.defaultbuttons.rightnav[2]+'px', cursor:'hand', cursor:'pointer'}).attr({title:'Forward '+config.defaultbuttons.moveby+' panels'}).appendTo('body')
			config.$leftnavbutton=$('<img src="'+config.defaultbuttons.leftnav[0]+'">').css({zIndex:50, position:'relative', right:'-20px', cursor:'hand', cursor:'pointer'}).attr({title:'Back '+config.defaultbuttons.moveby+' panels'}).appendTo('#mygallery_prev')
			config.$rightnavbutton=$('<img src="'+config.defaultbuttons.rightnav[0]+'">').css({zIndex:50, position:'relative', left:'-20px', cursor:'hand', cursor:'pointer'}).attr({title:'Forward '+config.defaultbuttons.moveby+' panels'}).appendTo('#mygallery_next')
			config.$leftnavbutton.bind('click', function(){ //assign nav button event handlers
				stepcarousel.stepBy(config.galleryid, -config.defaultbuttons.moveby)
			})
			config.$rightnavbutton.bind('click', function(){ //assign nav button event handlers
				stepcarousel.stepBy(config.galleryid, config.defaultbuttons.moveby)
			})
			if (config.panelbehavior.wraparound==false){ //if carousel viewer should stop at first or last panel (instead of wrap back or forth)
				this.fadebuttons(config, currentpanel)
			}
			return config.$leftnavbutton.add(config.$rightnavbutton)
		},
	
		stopautostep:function(config){
			clearTimeout(config.steptimer)
			clearTimeout(config.resumeautostep)
		},
	
		alignpanels:function($, config){
			var paneloffset=0
			config.paneloffsets=[paneloffset] //array to store upper left offset of each panel (1st element=0)
			config.panelwidths=[] //array to store widths of each panel
			config.$panels.each(function(index){ //loop through panels
				var $currentpanel=$(this)
				$currentpanel.css({float: 'none', position: 'absolute', left: paneloffset+'px'}) //position panel
				$currentpanel.bind('click', function(e){return config.onpanelclick(e.target)}) //bind onpanelclick() to onclick event
				paneloffset+=stepcarousel.getCSSValue($currentpanel.css('marginRight')) + parseInt($currentpanel.get(0).offsetWidth || $currentpanel.css('width')) //calculate next panel offset
				config.paneloffsets.push(paneloffset) //remember this offset
				config.panelwidths.push(paneloffset-config.paneloffsets[config.paneloffsets.length-2]) //remember panel width
			})
			config.paneloffsets.pop() //delete last offset (redundant)
			var addpanelwidths=0
			var lastpanelindex=config.$panels.length-1
			config.lastvisiblepanel=lastpanelindex
			for (var i=config.$panels.length-1; i>=0; i--){
				addpanelwidths+=(i==lastpanelindex? config.panelwidths[lastpanelindex] : config.paneloffsets[i+1]-config.paneloffsets[i])
				if (config.gallerywidth>addpanelwidths){
					config.lastvisiblepanel=i //calculate index of panel that when in 1st position reveals the very last panel all at once based on gallery width
				}
			}
			config.$belt.css({width: paneloffset+'px'}) //Set Belt DIV to total panels' widths
			config.currentpanel=(config.panelbehavior.persist)? parseInt(this.getCookie(window[config.galleryid+"persist"])) : 0 //determine 1st panel to show by default
			config.currentpanel=(typeof config.currentpanel=="number" && config.currentpanel<config.$panels.length)? config.currentpanel : 0
			if (config.currentpanel!=0){
				var endpoint=config.paneloffsets[config.currentpanel]+(config.currentpanel==0? 0 : config.beltoffset)
				config.$belt.css({left: -endpoint+'px'})
			}
			if (config.defaultbuttons.enable==true){ //if enable default back/forth nav buttons
				var $navbuttons=this.addnavbuttons(config, config.currentpanel)
				$(window).bind("load resize", function(){ //refresh position of nav buttons when page loads/resizes, in case offsets weren't available document.oncontentload
					config.offsets={left:stepcarousel.getoffset(config.$gallery.get(0), "offsetLeft"), top:stepcarousel.getoffset(config.$gallery.get(0), "offsetTop")}
					// config.$leftnavbutton.css({left:config.offsets.left+config.defaultbuttons.leftnav[1]+'px', top:config.offsets.top+config.defaultbuttons.leftnav[2]+'px'})
					// config.$rightnavbutton.css({left:config.offsets.left+config.$gallery.get(0).offsetWidth+config.defaultbuttons.rightnav[1]+'px', top:config.offsets.top+config.defaultbuttons.rightnav[2]+'px'})
					config.$leftnavbutton.css({right:'-20px'})
					config.$rightnavbutton.css({left:'-20px'})
				})
			}
			if (config.autostep && config.autostep.enable){ //enable auto stepping of Carousel?		
				var $carouselparts=config.$gallery.add(typeof $navbuttons!="undefined"? $navbuttons : null)
				$carouselparts.bind('click', function(){
					stepcarousel.stopautostep(config)
					config.autostep.status="stopped"
				})
				$carouselparts.hover(function(){ //onMouseover
					stepcarousel.stopautostep(config)
					config.autostep.hoverstate="over"
				}, function(){ //onMouseout
					if (config.steptimer && config.autostep.hoverstate=="over" && config.autostep.status!="stopped"){
						config.resumeautostep=setTimeout(function(){
							stepcarousel.autorotate(config.galleryid)
							config.autostep.hoverstate="out"
						}, 500)
					}
				})
				config.steptimer=setTimeout(function(){stepcarousel.autorotate(config.galleryid)}, config.autostep.pause) //automatically rotate Carousel Viewer
			} //end enable auto stepping check
			this.statusreport(config.galleryid)
			config.oninit()
			config.onslideaction(this)
		},
	
		stepTo:function(galleryid, pindex){ /*User entered pindex starts at 1 for intuitiveness. Internally pindex still starts at 0 */
			var config=stepcarousel.configholder[galleryid]
			if (typeof config=="undefined"){
				alert("There's an error with your set up of Carousel Viewer \""+galleryid+ "\"!")
				return
			}
			stepcarousel.stopautostep(config)
			var pindex=Math.min(pindex-1, config.paneloffsets.length-1)
			var endpoint=config.paneloffsets[pindex]+(pindex==0? 0 : config.beltoffset)
			if (config.panelbehavior.wraparound==false && config.defaultbuttons.enable==true){ //if carousel viewer should stop at first or last panel (instead of wrap back or forth)
				this.fadebuttons(config, pindex)
			}
			config.$belt.animate({left: -endpoint+'px'}, config.panelbehavior.speed, function(){config.onslideaction(this)})
			config.currentpanel=pindex
			this.statusreport(galleryid)
		},
	
		stepBy:function(galleryid, steps){ //isauto if defined indicates stepBy() is being called automatically
			var config=stepcarousel.configholder[galleryid]
			if (typeof config=="undefined"){
				alert("There's an error with your set up of Carousel Viewer \""+galleryid+ "\"!")
				return
			}
			stepcarousel.stopautostep(config)
			var direction=(steps>0)? 'forward' : 'back' //If "steps" is negative, that means backwards
			var pindex=config.currentpanel+steps //index of panel to stop at
			if (config.panelbehavior.wraparound==false){ //if carousel viewer should stop at first or last panel (instead of wrap back or forth)
				pindex=(direction=="back" && pindex<=0)? 0 : (direction=="forward")? Math.min(pindex, config.lastvisiblepanel) : pindex
				if (config.defaultbuttons.enable==true){ //if default nav buttons are enabled, fade them in and out depending on if at start or end of carousel
					stepcarousel.fadebuttons(config, pindex)
				}	
			}
			else{ //else, for normal stepBy behavior
				if (pindex>config.lastvisiblepanel && direction=="forward"){
					//if destination pindex is greater than last visible panel, yet we're currently not at the end of the carousel yet
					pindex=(config.currentpanel<config.lastvisiblepanel)? config.lastvisiblepanel : 0
				}
				else if (pindex<0 && direction=="back"){
					//if destination pindex is less than 0, yet we're currently not at the beginning of the carousel yet
					pindex=(config.currentpanel>0)? 0 : config.lastvisiblepanel /*wrap around left*/
				}
			}
			var endpoint=config.paneloffsets[pindex]+(pindex==0? 0 : config.beltoffset) //left distance for Belt DIV to travel to
			if (pindex==0 && direction=='forward' || config.currentpanel==0 && direction=='back' && config.panelbehavior.wraparound==true){ //decide whether to apply "push pull" effect
				config.$belt.animate({left: -config.paneloffsets[config.currentpanel]-(direction=='forward'? 100 : -30)+'px'}, 'normal', function(){
					config.$belt.animate({left: -endpoint+'px'}, config.panelbehavior.speed, function(){config.onslideaction(this)})
				})
			}
			else
				config.$belt.animate({left: -endpoint+'px'}, config.panelbehavior.speed, function(){config.onslideaction(this)})
			config.currentpanel=pindex
			this.statusreport(galleryid)
		},
	
		autorotate:function(galleryid){
			var config=stepcarousel.configholder[galleryid]
			if (config.$gallery.attr('_ismouseover')!="yes"){
				this.stepBy(galleryid, config.autostep.moveby)
			}
			config.steptimer=setTimeout(function(){stepcarousel.autorotate(galleryid)}, config.autostep.pause)
		},
	
		statusreport:function(galleryid){
			var config=stepcarousel.configholder[galleryid]
			var startpoint=config.currentpanel //index of first visible panel 
			var visiblewidth=0
			for (var endpoint=startpoint; endpoint<config.paneloffsets.length; endpoint++){ //index (endpoint) of last visible panel
				visiblewidth+=config.panelwidths[endpoint]
				if (visiblewidth>config.gallerywidth){
					break
				}
			}
			startpoint+=1 //format startpoint for user friendiness
			endpoint=(endpoint+1==startpoint)? startpoint : endpoint //If only one image visible on the screen and partially hidden, set endpoint to startpoint
			var valuearray=[startpoint, endpoint, config.panelwidths.length]
			for (var i=0; i<config.statusvars.length; i++){
				window[config.statusvars[i]]=valuearray[i] //Define variable (with user specified name) and set to one of the status values
				config.$statusobjs[i].text(valuearray[i]+" ") //Populate element on page with ID="user specified name" with one of the status values
			}
		},
	
		setup:function(config){
			//Disable Step Gallery scrollbars ASAP dynamically (enabled for sake of users with JS disabled)
			document.write('<style type="text/css">\n#'+config.galleryid+'{overflow: hidden;}\n</style>')
			jQuery(document).ready(function($){
				config.$gallery=$('#'+config.galleryid)
				config.gallerywidth=config.$gallery.width()
				config.offsets={left:stepcarousel.getoffset(config.$gallery.get(0), "offsetLeft"), top:stepcarousel.getoffset(config.$gallery.get(0), "offsetTop")}
				config.$belt=config.$gallery.find('.'+config.beltclass) //Find Belt DIV that contains all the panels
				config.$panels=config.$gallery.find('.'+config.panelclass) //Find Panel DIVs that each contain a slide
				config.panelbehavior.wraparound=(config.autostep && config.autostep.enable)? true : config.panelbehavior.wraparound //if auto step enabled, set "wraparound" to true
				config.onpanelclick=(typeof config.onpanelclick=="undefined")? function(target){} : config.onpanelclick //attach custom "onpanelclick" event handler
				config.onslideaction=(typeof config.onslide=="undefined")? function(){} : function(beltobj){$(beltobj).stop(); config.onslide()} //attach custom "onslide" event handler
				config.oninit=(typeof config.oninit=="undefined")? function(){} : config.oninit //attach custom "oninit" event handler
				config.beltoffset=stepcarousel.getCSSValue(config.$belt.css('marginLeft')) //Find length of Belt DIV's left margin
				config.statusvars=config.statusvars || []  //get variable names that will hold "start", "end", and "total" slides info
				config.$statusobjs=[$('#'+config.statusvars[0]), $('#'+config.statusvars[1]), $('#'+config.statusvars[2])]
				config.currentpanel=0
				stepcarousel.configholder[config.galleryid]=config //store config parameter as a variable
				if (config.contenttype[0]=="ajax" && typeof config.contenttype[1]!="undefined") //fetch ajax content?
					stepcarousel.getremotepanels($, config)
				else
					stepcarousel.alignpanels($, config) //align panels and initialize gallery
			}) //end document.ready
			jQuery(window).bind('unload', function(){ //clean up
				if (config.panelbehavior.persist){
					stepcarousel.setCookie(window[config.galleryid+"persist"], config.currentpanel)
				}
				jQuery.each(config, function(ai, oi){
					oi=null
				})
				config=null
			})
		}
	}
})(jQuery)