if(typeof(DM) == "undefined") { DM={}; }
DM.gallery = {

	// the current page
	p: 0,

	// number of pages
	np: 0,

	// the current image
	i: 0,

	// number of images
	ni: 0,

	// number of images per page
	ipp: 0,

	// width of slider area
	w: 580,

	// width of a single thumbnail
	t: 110,

	// image data
	imagedata: new Array(),

	// prepare for use
	init: function() {
		this.ni = $("#gallery-thumbs ul li").size() -1;
		this.np = Math.ceil( ((this.t * this.ni)  / this.w) ) -1;
		this.ipp = Math.ceil( this.w / this.t );

		// loop all thumbnails
		c = 0;
		$("#gallery-thumbs ul li").each(function(){
			// store all image data
			a = $(this).find("a");
			$(this).data("counter",c).attr("id","thumb"+c);
			DM.gallery.imagedata.push( {image: a.attr("href"),
										caption: a.attr("title"),
										page: DM.gallery.getPage(c),
										download: a.attr("href").replace('_medium.','.')}  )

			// remove the anchor tags
			$(this).html(a.html());

			c ++;
		})

		// navigation buttons
		this.setPageNav();
		this.setImgNav();

		// load the first image
		$("#gallery-image-main").attr("src",this.imagedata[0].image);
		$("#gallery-caption").text(this.imagedata[0].caption);
		$("#gallery-thumbs ul li#thumb0").addClass("current");
		this.showDownload(this.imagedata[0].download);
	},

	getPage: function(imageNum) {
		return Math.ceil( (imageNum+1) / this.ipp) - 1;
	},

	// advance image back and forth
	imgNav: function(dir) {

		// requested image
		r = this.i + dir;

		// prevent out of range
		if(r < 0 || r > this.ni) {
			return;
		}

		// load the image
		this.imgLoad(r)

	},

	// load an image into the main area
	imgLoad: function(ref) {
		// swap image
		$("#gallery-image-main").fadeOut(200,function(){
			$("#gallery-image-main").attr( {src:DM.gallery.imagedata[ref].image} ).fadeIn();
		})

		// swap caption
		$("#gallery-caption").fadeOut(200,function(){
			$("#gallery-caption").text( DM.gallery.imagedata[ref].caption ).fadeIn();
		})

		// log image
		this.i = ref;

		// ensure we're on the correct page
		myPage = this.imagedata[ref].page;
		if(myPage != this.p) {
			this.jumpto(myPage);
		}

		// highlight thumbnail
		$("#gallery-thumbs ul li").removeClass("current");
		$("#gallery-thumbs ul li#thumb"+ref).addClass("current");

		// set download
		this.showDownload(this.imagedata[ref].download);

		this.setImgNav();
	},

	// animate one page up or down
	animate:function(dir){

		// requested page
		r = this.p + dir;

		// prevent out of range
		if(r < 0 || r > this.np) {
			return;
		}

		// confirm next page
		this.p = r;

		// animate element to new position
		$("#gallery-thumbs ul").animate( {left:(this.p * this.w) * -1+"px"}, 1000, 'swing' );

		this.setPageNav();
	},

	// go directly to a given page
	jumpto:function(page) {

		// reset current page
		this.p = page;

		// jump element into view
		$("#gallery-thumbs ul").animate( {left:(this.p * this.w) * -1+"px"}, 1000, 'swing' );

		this.setPageNav();
	},

	// set appropriate state for page navigation buttons
	setPageNav: function() {

		// next page button
		if(this.np == 0 || this.p == this.np) {
			$("#gallery-np").removeClass("gallery-activepnav");
		} else {
			$("#gallery-np").addClass("gallery-activepnav");
		}

		// previous page button
		if(this.np == 0 || this.p == 0) {
			$("#gallery-pp").removeClass("gallery-activepnav");
		} else {
			$("#gallery-pp").addClass("gallery-activepnav");
		}
	},

	// set appropriate state for image navigation buttons
	setImgNav: function() {

		// next image button
		if(this.ni < 2 || this.i == this.ni) {
			$("#gallery-ni").removeClass("gallery-activeinav");
		} else {
			$("#gallery-ni").addClass("gallery-activeinav");
		}

		// previous image button
		if(this.ni < 2 || this.i == 0) {
			$("#gallery-pi").removeClass("gallery-activeinav");
		} else {
			$("#gallery-pi").addClass("gallery-activeinav");
		}
	},

	showDownload: function(d) {
		$("#gallery-download").html('<a href="'+d+'" target="_blank">Download</a>')
	}

};

$(function(){
	DM.gallery.init();

	// event handlers

		// page navigation
		$("#gallery-np.gallery-activepnav").live("click",function(){	DM.gallery.animate(1) })
		$("#gallery-pp.gallery-activepnav").live("click",function(){	DM.gallery.animate(-1) })

		// thubnail clicks
		$("#gallery-thumbs ul li").click(function(){ DM.gallery.imgLoad($(this).data("counter")) }).hover(
			function(){$(this).addClass("over")},
			function(){$(this).removeClass("over")}
		)

		// image navigation
		$("#gallery-ni.gallery-activeinav").live("click",function(){	DM.gallery.imgNav(1) })
		$("#gallery-pi.gallery-activeinav").live("click",function(){	DM.gallery.imgNav(-1) })

});