// Copyright (c) 2007 Ganeshji Marwaha (gmarwaha.com)
// Dual licensed under the MIT and GPL licenses:
// http://www.opensource.org/licenses/mit-license.php
// http://www.gnu.org/licenses/gpl.html
(function($) {
    $.fn.jCarouselLite = function(o) {
        o = $.extend({
            btnNext: ".next",
            btnPrev: ".prev",
            btnGo: null,
            mouseWheel: false,
            auto: null,
            speed: 600,
            easing: null,
            vertical: false,
            circular: false,
            visible: 3,
            start: 0,
            scroll: 3,
            beforeStart: null,
            afterEnd: null
        }, o || {});
        return this.each(function() {
            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+1).clone())
                .append(tLi.slice(0,v).clone());
                o.start += v;
            }
            var li = $("li", ul), itemLength = li.size(), curr = o.start;
            if (/MSIE (\d+\.\d+);/.test(navigator.userAgent)){
                var ieversion=new Number(RegExp.$1)
            }
            div.css("visibility", "visible");
            li.css({
                overflow: "hidden",
                float: o.vertical ? "none" : "left"
                });
            ul.css({
                margin: "0",
                padding: "0",
                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);
            var ulSize = liSize * itemLength;
            var divSize = liSize * v;
            li.css({
                width: li.width(),
                height: li.height()
                });
            ul.css(sizeCss, ulSize+"px").css(animCss, -(curr*liSize));
            div.css(sizeCss, divSize+"px");
            if(!o.circular) {
                $(o.btnPrev + ',' + o.btnNext).removeClass("disabled");
                if (o.btnPrev && curr == 0){
                    $(o.btnPrev).addClass("disabled");
                }
                if (o.btnNext && curr >= itemLength-v){
                    $(o.btnNext).addClass("disabled");
                }
                if (ieversion<=6)
                    if (o.btnNext && curr >= itemLength-v-1){
                        $(o.btnNext).addClass("disabled");
                    }
            }
            if(o.btnPrev)
                $(o.btnPrev).click(function() {
                    prev = curr-o.scroll;
                    if (!o.circular && prev < 0){
                        prev = 0;
                    }
                    return go(prev);
                });
            if(o.btnNext)
                $(o.btnNext).click(function() {
                    next = curr+o.scroll;
                    if (!o.circular && next > itemLength-v-1){
                        if (ieversion<=6)
                            next = itemLength-v-1;
                        else
                            next = itemLength-v;
                    }
                    return go(next);
                });
            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);
                });
            if(o.auto)
                setInterval(function() {
                    go(curr+o.scroll);
                }, o.auto+o.speed);
            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(to<=o.start-v-1) {
                            ul.css(animCss, -((itemLength-(v*2))*liSize)+"px");
                            curr = to==o.start-v-1 ? itemLength-(v*2)-1 : itemLength-(v*2)-o.scroll;
                        } else if(to>=itemLength-v+1) {
                            ul.css(animCss, -( (v) * liSize ) + "px" );
                            curr = to==itemLength-v+1 ? v+1 : v+o.scroll;
                        } else curr = to;
                    } else {
                        if(to<0 || to>itemLength-v) return;
                        else curr = to;
                    }
                    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;
                        }
                        );
                    if(!o.circular) {
                        $(o.btnPrev + ',' + o.btnNext).removeClass("disabled");
                        if (o.btnPrev && curr == 0){
                            $(o.btnPrev).addClass("disabled");
                        }
                        if (o.btnNext && curr >= itemLength-v){
                            $(o.btnNext).addClass("disabled");
                        }
                        if (ieversion<=6)
                            if (o.btnNext && curr >= itemLength-v-1){
                                $(o.btnNext).addClass("disabled");
                            }
                    }
                }
                return false;
            };
        });
    };
    function css(el, prop) {
        return parseInt($.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');
    };
})($);