//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.$leftnavbutton=$('<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.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
        var clip_elements = config.panelbehavior.clip_elements;
        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
				var animate = true;

				if((direction == 'forward') && (clip_elements > 1)){
				 // forward and tail - 1 && clip_elements = 2.
         if((pindex + 1) >  config.lastvisiblepanel){
						// 1. Set currentpanel = last element;
						// 2. Set pindex = first element;
						// 3. Recalculate new end point.
						config.currentpanel = pindex;
						pindex = 0;
						endpoint = config.paneloffsets[pindex] + (pindex == 0 ? 0 : config.beltoffset);
         }
        }else if((direction == 'back') && (clip_elements > 1)){
					// back & current panel is head.
					if(config.currentpanel == 0){
						// 1. Set pindex = tail - 1;
						// 2. Recalculate new end point.
						pindex -= 1;
						endpoint = config.paneloffsets[pindex] + (pindex == 0 ? 0 : config.beltoffset);
					}
				}

				if(animate){
	        if (pindex == 0 && direction == 'forward' || config.currentpanel == 0 && direction == 'back' && config.panelbehavior.wraparound == true) { 
				if(clip_elements > 1){
	            	config.$belt.animate({ left: -config.paneloffsets[(config.currentpanel > 0 ? config.currentpanel - 1 : config.currentpanel)] - (direction == 'forward' ? 50 : -30) + 'px' }, 'normal', function() {
	                	config.$belt.animate({ left: -endpoint + 'px' }, config.panelbehavior.speed, function() { config.onslideaction(this) })
	            	});								
				}else {
	            	config.$belt.animate({ left: -config.paneloffsets[config.currentpanel] - (direction == 'forward' ? 50 : -30) + 'px' }, 'normal', function() {
	                	config.$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++) {
					try { 
						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
					}catch(e){ /* supress warnings if a none existant element, different behavior in browsers. */ }
        }
    },

    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 trues
            config.panelbehavior.clip_elements = (typeof(config.panelbehavior.clip_elements) == "undefined" ? 1 : config.panelbehavior.clip_elements);
            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.$statusobjs = [];
						try {
							config.$statusobjs = [$('#' + config.statusvars[0]), $('#' + config.statusvars[1]), $('#' + config.statusvars[2])];
						}catch(e){}
            config.currentpanel = 0;
            stepcarousel.configholder[config.galleryid] = config //store config parameter as a variable
            if (config.contenttype[0] == "ajax" && typeof config.contenttype[1] != "undefined") //fetch ajax content?
                stepcarousel.getremotepanels($, 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
        })
    }
}