/**
 * @author Stéphane Roucheray
 * @extends jquery
 */


jQuery.fn.carousel = function(previous, next, options){
        var sliderList = jQuery(this).children()[0];

        if (sliderList) {
                var increment = jQuery(sliderList).children().outerWidth("true"),
                elmnts = jQuery(sliderList).children(),
                numElmts = elmnts.length,
                sizeFirstElmnt = increment,
                shownInViewport = Math.round(jQuery(this).width() / sizeFirstElmnt),
                firstElementOnViewPort = 1,
                isAnimating = false;

                for (i = 0; i < shownInViewport; i++) {
                        jQuery(sliderList).css('width',(numElmts+shownInViewport)*increment + increment + "px");
                        jQuery(sliderList).append(jQuery(elmnts[i]).clone());
                }

                jQuery(previous).click(function(event){
                        event.preventDefault();
                        if (!isAnimating) {
                                if (firstElementOnViewPort == 1) {
                                        jQuery(sliderList).css('left', "-" + numElmts * sizeFirstElmnt + "px");
                                        firstElementOnViewPort = numElmts;
                                }
                                else {
                                        firstElementOnViewPort--;
                                }

                                jQuery(sliderList).animate({
                                        left: "+=" + increment,
                                        y: 0,
                                        queue: true
                                }, "swing", function(){isAnimating = false;});
                                isAnimating = true;
                        }

                });

                jQuery(next).click(function(event){
                        event.preventDefault();
                        if (!isAnimating) {
                                if (firstElementOnViewPort > numElmts) {
                                        firstElementOnViewPort = 2;
                                        jQuery(sliderList).css('left', "0px");
                                }
                                else {
                                        firstElementOnViewPort++;
                                }
                                jQuery(sliderList).animate({
                                        left: "-=" + increment,
                                        y: 0,
                                        queue: true
                                }, "swing", function(){isAnimating = false;});
                                isAnimating = true;
                        }
                });
        }
};