//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={

	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=jQuery('<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.$rightnavbutton=jQuery('<img src="'+config.defaultbuttons.rightnav[0]+'">').css({zIndex:50, position:'absolute', left:config.offsets.left+config.$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.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'})

			})

		}

		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

		})

	}

}