/*!
* jQuery jCarousellite Plugin v1.6.1
*
* Date: Sat Nov 19 23:55:07 2011 EST
* Requires: jQuery v1.4+
*
* Copyright 2007 Ganeshji Marwaha (gmarwaha.com)
* Modifications/enhancements by Karl Swedberg
* Dual licensed under the MIT and GPL licenses (just like jQuery):
* http://www.opensource.org/licenses/mit-license.php
* http://www.gnu.org/licenses/gpl.html
*
* jQuery plugin to navigate images/any content in a carousel style widget.
*
*/

(function($) {

    $.jCarouselLite = {
        version: '1.6.1',
        curr: 0
    };

    $.fn.jCarouselLite = function(options) {
        var o = $.extend({}, $.fn.jCarouselLite.defaults, options);

        this.each(function() {

            var sizes = {},
            running = false,
            animCss = o.vertical ? "top": "left",
            aniProps = {},
            sizeProp = o.vertical ? "height": "width",
            self = this,
            div = $(this),
            ul = div.find('ul').eq(0),
            tLi = ul.children('li'),
            tl = tLi.length,
            v = o.visible,
            start = Math.min(o.start, tl - 1);
            direction = 1;

            div.data('dirjc', direction);

            if (o.circular) {
                ul.prepend(tLi.slice(tl-v-1+1).clone(true))
                .append(tLi.slice(0,v).clone(true));
                start += v;
            }
            var li = ul.children('li'),
            itemLength = li.length,
            curr = start;

            $.jCarouselLite.curr = curr;

            div.css("visibility", "visible");

            if (o.autoCSS) {
                li.css({
                    overflow: o.vertical ? 'hidden' : 'visible', 
                    'float': o.vertical ? 'none' : 'left'
                    });
                ul.css({
                    margin: '0', 
                    padding: '0', 
                    position: 'relative', 
                    listStyleType: 'none', 
                    zIndex: 1
                });
                div.css({
                    visibility: 'visible', 
                    overflow: 'hidden', 
                    position: 'relative', 
                    zIndex: 2, 
                    left: '0px'
                });
            }

            // Full li size(incl margin)-Used for animation
            var liSize = o.vertical ? height(li) : width(li);

            // size of full ul(total length, not just for the visible items)
            var ulSize = liSize * itemLength;

            // size of entire div(total length for just the visible items)
            var divSize = liSize * v;

            if (o.autoCSS) {
                sizes[sizeProp] = divSize + 'px';
                div.css(sizes);
                li.css({
                    width: li.width(), 
                    height: li.height()
                    });
            }

            sizes[sizeProp] = ulSize + 'px';
            sizes[animCss] = -(curr*liSize);
            ul.css(sizes);

            // set up timed advancer
            var advanceCounter = 0,
            autoStop = iterations(tl,o),
            autoScrollBy = typeof o.auto == 'number' ? o.auto : o.scroll;

            var advancer = function() {
                self.setAutoAdvance = setTimeout(function() {

                    if (!autoStop || autoStop > advanceCounter) {
                        direction = div.data('dirjc');
                        go( curr + (direction * autoScrollBy) );
                        advanceCounter++;
                        advancer();
                    }
                }, o.timeout + o.speed);
            };

            // bind click handlers to prev and next buttons, if set
            $.each([ 'btnPrev', 'btnNext' ], function(index, btn) {
                if ( o[btn] ) {
                    o['$' + btn] = $.isFunction( o[btn] ) ? o[btn].call( div[0] ) : $( o[btn] );

                    o['$' + btn].bind('click.jc', function() {
                        var step = index === 0 ? curr-o.scroll : curr+o.scroll;
                        if (o.directional) {
                            // set direction of subsequent scrolls to:
                            // 1 if "btnNext" clicked
                            // -1 if "btnPrev" clicked
                            div.data( 'dirjc', ((index) ? 1 : -1) );
                        }
                        return go( step );
                    });
                }
            });

            if (!o.circular) {
                if (o.btnPrev && start === 0) {
                    o.$btnPrev.addClass(o.btnDisabledClass);
                }

                if ( o.btnNext && start + o.visible >= itemLength ) {
                    o.$btnNext.addClass(o.btnDisabledClass);
                }
            }

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

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

            if (o.pause && o.auto) {
                div.bind('mouseenter.jc', function() {
                    div.trigger('pauseCarousel.jc');
                }).bind('mouseleave.jc', function() {
                    div.trigger('resumeCarousel.jc');
                });
            }

            if (o.auto) {
                advancer();
            }

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

            $.jCarouselLite.vis = vis;

            function go(to) {
                if (running) {
                    return false;
                }
                var direction = to > curr;
                if (o.beforeStart) {
                    o.beforeStart.call(this, vis(), direction);
                }
                // If circular we are in first or last, then goto the other end
                if (o.circular) {
                    // If first, then goto last
                    if (to <= start - v - 1) {
                        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 == 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;
                    }

                // If non-circular and to points beyond first or last, we change to first or last.
                } else {
                    // Disable buttons when the carousel reaches the last/first, and enable when not
                    o.$btnPrev.toggleClass(o.btnDisabledClass, o.btnPrev && to <= 0);
                    o.$btnNext.toggleClass(o.btnDisabledClass, o.btnNext && to > itemLength - v);

                    if (to < 0) {
                        curr = 0;
                    } else if (to > itemLength - v) {
                        curr = itemLength - v;
                    } else {
                        curr = to;
                    }
                }
                $.jCarouselLite.curr = curr;
                running = true;
                aniProps[animCss] = -(curr * liSize);

                ul.animate(aniProps, o.speed, o.easing, function() {
                    if (o.afterEnd) {
                        o.afterEnd.call(this, vis(), direction);
                    }
                    running = false;
                });
                return false;
            } // end go function

            // bind custom events so they can be triggered by user
            div
            .bind('go.jc', function(e, to) {
                if (typeof to == 'undefined') {
                    to = '+=1';
                }

                var todir = typeof to == 'string' && /(\+=|-=)(\d+)/.exec(to);

                if ( todir ) {
                    to = todir[1] == '-=' ? curr - todir[2] * 1 : curr + todir[2] * 1;
                } else {
                    to += start;
                }
                go(to);
            })
            .bind('startCarousel.jc', function(event) {
                clearTimeout(self.setAutoAdvance);
                self.setAutoAdvance = undefined;
                div.trigger('go', '+=' + o.scroll);
                advancer();
                div.removeData('pausedjc').removeData('stoppedjc');
            })
            .bind('resumeCarousel.jc', function(event, forceRun) {
                if (self.setAutoAdvance) {
                    return;
                }
                clearTimeout(self.setAutoAdvance);
                self.setAutoAdvance = undefined;

                var stopped = div.data('stoppedjc');
                if ( forceRun || !stopped ) {
                    advancer();
                    div.removeData('pausedjc');
                    if (stopped) {
                        div.removeData('stoppedjc');
                    }
                }
            })

            .bind('pauseCarousel.jc', function(event) {
                clearTimeout(self.setAutoAdvance);
                self.setAutoAdvance = undefined;
                div.data('pausedjc', true);
            })
            .bind('stopCarousel.jc', function(event) {
                clearTimeout(self.setAutoAdvance);
                self.setAutoAdvance = undefined;

                div.data('stoppedjc', true);
            })

            .bind('endCarousel.jc', function() {
                if (self.setAutoAdvance) {
                    clearTimeout(self.setAutoAdvance);
                    self.setAutoAdvance = undefined;
                }
                if (o.btnPrev) {
                    o[$btnPrev].addClass(o.btnDisabledClass).unbind('.jc');
                }
                if (o.btnNext) {
                    o[$btnNext].addClass(o.btnDisabledClass).unbind('.jc');
                }
                if (o.btnGo) {
                    $.each(o.btnGo, function(i, val) {
                        $(val).unbind('.jc');
                    });
                }
                $.each(['pausedjc', 'stoppedjc', 'dirjc'], function(i, d) {
                    div.removeData(d);
                });
                div.unbind('.jc');
            });
        });

        return this;
    };
    $.fn.jCarouselLite.defaults = {
        autoCSS: true,
        btnPrev: null,
        btnNext: null,
        btnDisabledClass: 'disabled',
        btnGo: null,
        mouseWheel: false,

        speed: 200,
        easing: null,

        // milliseconds between scrolls
        timeout: 4000,

        // true to enable auto scrolling; number to auto-scroll by different number at a time than that of scroll option
        auto: false,

        // true to enable changing direction of auto scrolling when user clicks prev or next button
        directional: false,

        // number of times before autoscrolling will stop. (if circular is false, won't iterate more than number of items)
        autoStop: false,

        // pause scrolling on hover
        pause: true,

        vertical: false,

        // continue scrolling when reach the last item
        circular: true,

        // the number to be visible at a given time.
        visible: 3,

        // index of item to show initially in the first posiition
        start: 0,

        // number of items to scroll at a time
        scroll: 1,

        // function to be called before each transition starts
        beforeStart: null,

        // function to be called after each transition ends
        afterEnd: null
    };

    function css(el, prop) {
        return parseInt($.css(el[0], prop), 10) || 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');
    }
    function iterations(itemLength, options) {
        return options.autoStop && (options.circular ? options.autoStop : Math.min(itemLength, options.autoStop));
    }
})(jQuery);