/**
 * jCarouselLite - jQuery plugin to navigate images/any content in a carousel style widget.
 * @requires jQuery v1.2 or above
 *
 * http://gmarwaha.com/jquery/jcarousellite/
 *
 * 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
 *
 * Version: 1.0.1
 * Note: Requires jquery 1.2 or above from version 1.0.1
 */

/*
 * modified july 2010, wesley bliss
 * www.protocuturecomplex.net
 *
 */

(function($) { // Compliant with jquery.noConflict()
    
    $.fn.jCarouselLite = function( o ) {
        
        o = $.extend({
            btnPrev: null,
            btnNext: null,
            btnGo: null,
            mouseWheel: false,
            auto: null,
            
            speed: 200,
            easing: null,
            
            vertical: false,
            circular: true,
            visible: 3,
            start: 0,
            scroll: 1,
            
            beforeStart: null,
            afterEnd: null,
            
            /* allow multi-line scrolling! */
            rows: 1
            
        },
        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 + 1).clone() ).append( tLi.slice(0, v).clone() );
                o.start += v;
            }
            
            //var li = $('li', ul),
            //    itemLength = ( li.size() / o.rows ), /* modified for rows */
            //    curr = o.start;
            var li = $('li', ul);
            
            // DEBUG
            /*try {
                console.log(
                    "jCarouselLite : DEBUG\n\t" +
                    'li.length = ' + li.length + "\n\t" +
                    'itemLength = ( ' + li.length + '/' + o.rows + ')'
                );
            } catch( e ) {}
            */
            
            var itemLength = ( li.length / o.rows ), /* modified for rows */
                curr = o.start;
            
            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); // full LI size, including 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)
            
            // DEBUG
            /*try {
                console.log(
                    "\t" + 'ulSize = ' + ulSize + "\n\t" +
                    'liSize = ' + liSize + "\n\t" +
                    'o.rows = ' + o.rows + "\n\t" +
                    'itemLength = ' + itemLength + "\n"
                );
            } catch( e ) {}
            */
            
            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(e) {
                e.preventDefault();
                $(this).blur();
                //trace('jCarousel - goin up');
                return go(curr - o.scroll,true);
            });
            
            if (o.btnNext) $(o.btnNext).click(function(e) {
                e.preventDefault();
                //trace('jCarousel - goin down');
                trace( 'curr = ' + curr + ', o.scroll = ' + o.scroll );
                $(this).blur();
                return go(curr + o.scroll);
            });
            
            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) {
                
                var isprev = false;
                if ( arguments.length == 2 ) {
                    isprev = ( arguments[1] ? true : false );
                }
                
                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 <= o.start - v - 1) { // If first, then goto last
                            ul.css(animCss, -((itemLength - (v * 2)) * liSize) + "px");
                            // If "scroll" > 1, then the "to" might not be equal to the condition; it can be lesser depending on the number of elements.
                            curr = to == o.start - v - 1 ? itemLength - (v * 2) - 1 : itemLength - (v * 2) - o.scroll;
                        } else if (to >= itemLength - v + 1) { // If last, then goto first
                            ul.css(animCss, -((v) * liSize) + "px");
                            // If "scroll" > 1, then the "to" might not be equal to the condition; it can be greater depending on the number of elements.
                            curr = to == itemLength - v + 1 ? v + 1 : v + o.scroll;
                        } else curr = to;
                    } else { // If non-circular and to points to first or last, we just return.
                        //trace('if ' + to + ' < 0 || ' + to + ' > (' + itemLength + ' - ' + v + ')' );
                        //if (to < 0 || to > itemLength - v) return;
                        //else curr = to;
                        if ( (to < 0) || (to > (itemLength - v)) ) {
                            if ( to < 0 ) {
                                to = 0;
                                curr = 0;
                            }
                            else {
                                // for next
                                while ( to > 0 ) {
                                    if ( to < (itemLength - v) ) {
                                        curr = to;
                                        break;
                                    }
                                    to--;
                                }
                            }
                            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;
                    //trace(-( isprev ? 0 : (((curr <= 0) ? 1 /* min rows to animate */ : curr) * liSize) ) + 'px');
                    ul.animate(animCss == "left" ? {
                        left: -(curr * liSize) + 'px'
                    }: {
                        top: -( isprev ? 0 : (((curr <= 0) ? 1 /* min rows to animate */ : curr) * liSize) ) + 'px'
                    },
                    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);