var stepcarousel={
	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)
	},

	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.$leftnavbutton=$('<div class="leftlb1 '+config.defaultbuttons.leftnav[1]+'"><img src="'+config.defaultbuttons.leftnav[0]+'" width="10" height="24"></div>').css({"cursor":"pointer"}).appendto(config.$gallery)
    config.$rightnavbutton=$('<div class="rightlb1 '+config.defaultbuttons.rightnav[1]+'"><img src="'+config.defaultbuttons.rightnav[0]+'" width="10" height="24"></div>').css({"cursor":"pointer"}).appendto(config.$gallery)
		
		config.$leftnavbutton.bind('click', function(){ //assign nav button event handlers
			clearinterval(config.steptimer)
			stepcarousel.stepby(config.galleryid, -config.defaultbuttons.moveby)
			config.steptimer=setinterval(function(){stepcarousel.stepby(config.galleryid, config.defaultbuttons.moveby)}, config.autostep.pause)
							
		})
		config.$rightnavbutton.bind('click', function(){ //assign nav button event handlers
			clearinterval(config.steptimer)
			stepcarousel.stepby(config.galleryid, config.defaultbuttons.moveby)
			config.steptimer=setinterval(function(){stepcarousel.stepby(config.galleryid, config.defaultbuttons.moveby)}, config.autostep.pause)
					
		})
		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)
	},


	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)
			
		}
		if (config.autostep && config.autostep.enable){ //enable auto stepping of carousel?		
			//var $carouselparts=config.$gallery.add(typeof $navbuttons!="undefined"? $navbuttons : null)
      var $carouselparts=config.$gallery.children(".qyrylblist").eq(0)		
			$carouselparts.bind('click', function(){
				clearinterval(config.steptimer)
			})
			$carouselparts.hover(function(){ //onmouseover
				clearinterval(config.steptimer)
			}, function(){ //onmouseout	
			    clearinterval(config.steptimer)
					config.steptimer=setinterval(function(){stepcarousel.stepby(config.galleryid, config.defaultbuttons.moveby)}, config.autostep.pause) //automatically rotate carousel viewer
			})
			config.steptimer=setinterval(function(){stepcarousel.stepby(config.galleryid, config.defaultbuttons.moveby)}, config.autostep.pause) //automatically rotate carousel viewer
		} //end enable auto stepping check
		this.statusreport(config.galleryid)
		config.oninit()
		config.onslideaction(this)
	},

	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)
	},


	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
		}
	},
  execute:function(config){
  	
  	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]), $('#'+config.statusvars[2])]
		config.currentpanel=0
		stepcarousel.configholder[config.galleryid]=config //store config parameter as a variable
		stepcarousel.alignpanels($, config) //align panels and initialize gallery
		
    
  	},
	setup:function(configs){
		//disable step gallery scrollbars asap dynamically (enabled for sake of users with js disabled)
		
		
		jquery(document).ready(function($){
			
		    for(var i=0;i<configs.length;i++){
		    		stepcarousel.execute(configs[i])
		    		//console.log(config.$leftnavbutton)
		    		
		    	}			
			
		}) //end document.ready
		jquery(window).bind('unload', function(){ //clean up
		for(var i=0;i<configs.length;i++){
			var config = configs[i]
			if (config.panelbehavior.persist){
				stepcarousel.setcookie(window[config.galleryid+"persist"], config.currentpanel)
			}
			jquery.each(config, function(ai, oi){
				oi=null
			})
		config=null
		}
		})
	}
}