/**
2 * jCarouselLite - jQuery plugin to navigate images/any content in a carousel style widget.
3 * @requires jQuery v1.2 or above
4 *
5 * http://gmarwaha.com/jquery/jcarousellite/
6 *
7 * Copyright (c) 2007 Ganeshji Marwaha (gmarwaha.com)
8 * Dual licensed under the MIT and GPL licenses:
9 * http://www.opensource.org/licenses/mit-license.php
10 * http://www.gnu.org/licenses/gpl.html
11 *
12 * Version: 1.0.1
13 * Note: Requires jquery 1.2 or above from version 1.0.1
14 */ 

(function($) { // Compliant with jquery.noConflict()
$.fn.jCarouselLite = function(o) {
	o = $.extend({
		btnPrev: null,
		btnNext: null,
		btnGo: null,
		mouseWheel: false,
		auto: null,
		hoverPause: false,
		speed: 200,
		easing: null,
		vertical: false,
		circular: true,
		visible: 3,
		start: 0,
		scroll: 1,
		beforeStart: null,
		afterEnd: null
	}, o || {});

	return this.each(function() { // Returns the element collection. Chainable.

		var running = false, animCss=o.vertical?"top":"left", sizeCss=o.vertical?"height":"width";
		var div = $(this), ul = $("ul", div), tLi = $("li", ul), tl = tLi.size(), v = o.visible;

		if(o.circular) {
			ul.prepend(tLi.slice(tl-v+1).clone())
				.append(tLi.slice(0,o.scroll).clone());
			o.start += v-1;
		}

		var li = $("li", ul), itemLength = li.size(), curr = o.start;
		div.css("visibility", "visible");

		li.css({overflow: "hidden", float: o.vertical ? "none" : "left"});
		ul.css({position: "relative", "list-style-type": "none", "z-index": "1"});
		div.css({overflow: "hidden", position: "relative", "z-index": "2", left: "0px"});

		var liSize = o.vertical ? height(li) : width(li); // Full li size(incl margin)-Used for animation
		var ulSize = liSize * itemLength; // size of full ul(total length, not just for the visible items)
		var divSize = liSize * v; // size of entire div(total length for just the visible items)

		li.css({width: li.width(), height: li.height()});
		ul.css(sizeCss, ulSize+"px").css(animCss, -(curr*liSize));

		div.css(sizeCss, divSize+"px"); // Width of the DIV. length of visible images
		
		if(o.btnPrev) {
			$(o.btnPrev).click(function() {
				return go(curr-o.scroll);
			});
			if(o.hoverPause) {
				$(o.btnPrev).hover(function(){stopAuto();}, function(){startAuto();});
			}
		} 
		
		if(o.btnNext) {
			$(o.btnNext).click(function() {
				return go(curr+o.scroll);
			});
			if(o.hoverPause) {
				$(o.btnNext).hover(function(){stopAuto();}, function(){startAuto();});
			}
		}

		if(o.btnGo)
			$.each(o.btnGo, function(i, val) {
				$(val).click(function() {
					return go(o.circular ? o.visible+i : i);
				});
			});

		if(o.mouseWheel && div.mousewheel)
			div.mousewheel(function(e, d) {
				return d>0 ? go(curr-o.scroll) : go(curr+o.scroll);
			});

		var autoInterval;

		function startAuto() {
			stopAuto();
			autoInterval = setInterval(function() {
					go(curr+o.scroll);
				}, o.auto+o.speed);
		};

		function stopAuto() {
			clearInterval(autoInterval);
		};

		if(o.auto) {
			if(o.hoverPause) {
				div.hover(function(){stopAuto();}, function(){startAuto();});
			}
			startAuto(); 
		};

		function vis() {
			return li.slice(curr).slice(0,v);
		};

		function go(to) {
			if(!running) {
				
				if(o.beforeStart)
					o.beforeStart.call(this, vis());
				
				if(o.circular) { 	/*If circular we are in first or last, then goto the other end*/
					if(to<0) { 		/* If before range, then go around*/
						ul.css(animCss, -( (curr + tl) * liSize)+"px");
						curr = to + tl;
					} else if(to>itemLength-v) { // If beyond range, then come around
						ul.css(animCss, -( (curr - tl) * liSize ) + "px" );
						curr = to - tl;
					} else curr = to;
				} else { /* If non-circular and to points to first or last, we just return.*/
					if(to<0 || to>itemLength-v) return;
					else curr = to;
				} /* If neither overrides it, the curr will still be "to" and we can proceed.*/

				running = true;

				ul.animate(
					animCss == "left" ? { left: -(curr*liSize) } : { top: -(curr*liSize) } , o.speed, o.easing,
					function() {
						if(o.afterEnd)
							o.afterEnd.call(this, vis());
						running = false;
					}
				);
				// Disable buttons when the carousel reaches the last/first, and enable when not
				if(!o.circular) {
					$(o.btnPrev + "," + o.btnNext).removeClass("disabled");
					$( (curr-o.scroll<0 && o.btnPrev)
						||
						(curr+o.scroll > itemLength-v && o.btnNext)
						||
						[]
					).addClass("disabled");
				}

			}
			return false;
		};
	});
};

function css(el, prop) {
	return parseInt($.css(el[0], prop)) || 0;
};
function width(el) {
	return el[0].offsetWidth + css(el, 'marginLeft') + css(el, 'marginRight');
};
function height(el) {
	return el[0].offsetHeight + css(el, 'marginTop') + css(el, 'marginBottom');
};
})(jQuery);