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

jQuery.fn.carousel = function(previous, next, prevCallBack, nextCallBack, position){
	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;
		
		if (position != undefined) {
			firstElementOnViewPort = position;
		}
		
		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){
			if (!isAnimating) {
				if (firstElementOnViewPort == 1) {
					jQuery(sliderList).css('left', "-" + numElmts * sizeFirstElmnt + "px");
					firstElementOnViewPort = numElmts;
				}
				else {
					firstElementOnViewPort--;
					slideshow_position = firstElementOnViewPort;
				}
				
				jQuery(sliderList).animate({
					left: "+=" + increment,
					y: 0,
					queue: true
				}, "swing", function(){isAnimating = false;});
				isAnimating = true;
				prevCallBack();
			}
			
		});
		
		jQuery(next).click(function(event){
			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;
				nextCallBack();
			}
		});
		
		$('.slideshow-indicator .item').click(function() {
			clearInterval(loop);
			loop = null;
			if (counter != ($(this).data('position')-1)) {
				$(sliderList).css('left', "-" + ($(this).data('position') * sizeFirstElmnt) + "px");			
				firstElementOnViewPort = $(this).data('position')+1;
				counter = $(this).data('position')-1;
				$('.first-item').trigger('click');
				$('.slideshow-indicator .item').attr('class', 'item');
				$('#item_' + ($(this).data('position')-1)).attr('class', 'item current');
				//
				setTimeout(function() {
					if (loop == null) {
						loop = setInterval(
							function() {
								$('.last-item').trigger('click');
								$('.slideshow-indicator .item').attr('class', 'item');
								if ($('#item_' + (counter+1)).length > 0) {
									counter++;
								} else {
									counter = 0;
								}
								$('#item_' + counter).attr('class', 'item current');
							},
						speed);
					}
				}, speed);
			}
		});
	}
};