$(function(){
	$('div.block').slideshow();
});

//create jQuery plugin
$.fn.slideshow = function(options){return new slideshow(this, options);}

//constructor
function slideshow(obj, options){this.init(obj,options)}

//prototype
slideshow.prototype = {
	init:function(obj, options) {
		this.options = $.extend({
			slides:'ul.gallery >li',
			nextBtn:'a.next',
			prevBtn:'a.prev',
			pagingHolder:'ul.switcher',
			pagingTag:'li',
			createPaging:false,
			autoPlay:true,
			dynamicLoad:false,
			imgAttr:'alt',
			effect:'fade',//fade, slideX, slideY,
			startSlide:false,
			switchTime:5000,
			animSpeed:1000
		},options);
		
		this.mainHolder = $(obj);
		this.slides = $(this.options.slides,this.mainHolder);		
		this.nextBtn = $(this.options.nextBtn,this.mainHolder);
		this.prevBtn = $(this.options.prevBtn,this.mainHolder);
		this.dynamicLoad = this.options.dynamicLoad;
		this.imgAttr = this.options.imgAttr;
		this.animSpeed = this.options.animSpeed;
		this.switchTime = this.options.switchTime;
		this.effect = this.options.effect;
		this.autoPlay = this.options.autoPlay;
		this.previous = -1;
		this.loadingFrame = 1;
		this.busy = false;
		this.direction = 1;
		this.timer;
		this.pagingArray = new Array;
		this.loadArray = new Array;
		this.preloader = new Array;
		this.slidesParent = this.slides.eq(0).parent();
		this.slideW = this.slidesParent.width();
		this.slideH = this.slidesParent.height();
		
		(function(){
			if (this.options.startSlide) this.current = this.options.startSlide
			else {
				var active = -1;
				for(var i = 0; i< this.slides.length-1; i++) {
					if (this.slides.eq(i).hasClass('active')) {
						active = i;
						break;						
					}
				}
				if (active != -1) this.current = active;
				else this.current = 0;
			}
		}).apply(this);
		
		this.initPaging();
		this.setStyles();
		this.bindEvents();
		this.showSlide();
	},
	
	initPaging:function(){
		var obj = this;
		this.pagingHolder = $(this.options.pagingHolder,this.mainHolder);
		
		if (this.options.createPaging) {
			this.pagingHolder.each(function(i){
				var _this = $(this);
				_this.empty();
				var list = $('<ul>');
				for (var i = 0; i < obj.slides.length; i++) $('<li><a href="#">' + (i + 1) + '</a></li>').appendTo(list);
				_this.append(list);
			});
		}
		
		this.paging = $(this.options.pagingTag, this.pagingHolder);
		var ratio = Math.ceil(this.paging.length / this.slides.length);
		for (var i = 0; i < ratio; i++) {
			this.pagingArray.push(this.paging.slice(i*this.slides.length, (i*this.slides.length)+this.slides.length));
		}
	},
	
	setStyles:function(){
		//loader
		if (this.dynamicLoad) {
			this.loader = $('<div class="loader">');
			this.loaderDiv = $('<div>').appendTo(this.loader)
			this.loader.append(this.loaderDiv).appendTo(this.slidesParent);
		}
		
		//slides
		if (this.effect == 'fade') {
			this.slides.css({display:'none'});
			this.slides.eq(this.current).css({display:'block'});
		} else if (this.effect == 'slideX'){
			this.slides.css({display: 'none',left:-this.slideW});
			this.slides.eq(this.current).css({display:'block',left:0});
		} else if (this.effect == 'slideY'){
			this.slides.css({display:'none',top:-this.slideH});
			this.slides.eq(this.current).css({display:'block',top:0});
		}
	},
	
	bindEvents:function(){
		var obj = this;
		this.nextBtn.bind('click',function(){
			if (!obj.busy) obj.nextSlide();
			return false;
		});
		
		this.prevBtn.bind('click',function(){
			if (!obj.busy) obj.prevSlide();
			return false;
		});
		
		for (var i = 0; i < this.pagingArray.length; i++) {
			this.pagingArray[i].each(function(i){
				$(this).bind('click',function(){
					if (i != obj.current && !obj.busy) {
						obj.previous = obj.current;
						obj.current = i;
						if (obj.previous > i) obj.direction = -1
						else obj.direction = 1;
						obj.showSlide();
					}
					return false;
				});
			});
		}
		
		if (this.dynamicLoad) this.loader.bind('click',function(){
			obj.abortLoading();
		});
	},
	
	nextSlide:function(){
		this.previous = this.current;
		if (this.current < this.slides.length-1) this.current++
		else this.current = 0;
		this.direction = 1;
		this.showSlide();
	},
	
	prevSlide:function(){
		this.previous = this.current;
		if (this.current > 0) this.current--
		else this.current = this.slides.length-1;
		this.direction = -1;
		this.showSlide();
	},
	
	showSlide:function(){
		var obj = this;
		
		if (this.previous == this.current) return; 
		
		var _current = this.current;
		this.busy = true;
		clearTimeout(this.timer);
		
		if (typeof this.loadArray[_current] != 'undefined' || !this.dynamicLoad) {
			//slide already loaded
			this.switchSlide();
		
		} else {
			//slide not loaded
			this.showLoading();
			var images = $(this.dynamicLoad,this.slides.eq(this.current));
			if (images.length) {
				var counter = 0;
				images.each(function(){
					var preloader = new Image;
					obj.preloader.push(preloader);
					var img = $(this);
					preloader.onload = function(){
						counter++;
						checkImages();
					}
					preloader.onerror = function(){
						//ignore errors
						counter++;
						checkImages();
					}
					preloader.src = img.attr(obj.imgAttr);
				});
				
				function checkImages(){
					if (counter == images.length) {
						images.each(function(){
							var img = $(this);
							img.attr('src',img.attr(obj.imgAttr));
						});
						successLoad();
					}
				}
				
			} else successLoad();
		}
		
		function successLoad(){
			obj.loadArray[_current] = 1;
			obj.hideLoading();
			obj.switchSlide();
		}
	},
	
	switchSlide:function(){
		var obj = this;
		
		if (this.previous != -1) {
			var nextSlide = this.slides.eq(this.current);
			var prevSlide = this.slides.eq(this.previous);
			
			if (this.effect == 'fade') {
				nextSlide.css({display:'block',opacity:0}).animate({opacity:1},this.animSpeed,function(){
					$(this).css({opacity:'auto'});
				});
				prevSlide.animate({opacity:0},this.animSpeed,callback);
			} else if (this.effect == 'slideX'){
				nextSlide.css({display:'block',left:this.slideW*this.direction}).animate({left:0},this.animSpeed);
				prevSlide.animate({left:-this.slideW*this.direction},this.animSpeed+10,callback);
			} else if (this.effect == 'slideY'){
				nextSlide.css({display:'block',top:this.slideH*this.direction}).animate({top:0},this.animSpeed);
				prevSlide.animate({top:-this.slideH*this.direction},this.animSpeed+10,callback);
			}
		} else {
			if (this.autoPlay) this.startAutoPlay();
			this.busy = false;
		}
		
		this.refreshStatus();
		
		function callback(){
			prevSlide.css({display:'none'});
			if (obj.autoPlay) obj.startAutoPlay();
			obj.busy = false;
		}
	},
	
	refreshStatus:function(){
		for (var i = 0; i < this.pagingArray.length;i++) {
			this.pagingArray[i].eq(this.previous).removeClass('active');
			this.pagingArray[i].eq(this.current).addClass('active');
		}
		this.slides.eq(this.previous).removeClass('active');
		this.slides.eq(this.current).addClass('active');
	},
	
	showLoading:function(){
		var obj = this;
		this.loader.show();
		clearInterval(this.loadingTimer);
		obj.loadingTimer = setInterval(animateLoading, 66);
		
		function animateLoading(){
			obj.loaderDiv.css('top', obj.loadingFrame * -40);
			obj.loadingFrame = (obj.loadingFrame + 1) % 12;
		}
	},
	
	hideLoading:function(){
		this.loader.hide();
		clearInterval(this.loadingTimer);
	},
	
	abortLoading:function(){
		this.busy = false;
		this.hideLoading();
		this.current = this.previous;
		for (var i = 0; i < this.preloader.length; i++) {
			this.preloader[i].onload = null;
			this.preloader[i].onerror = null;
		}
		if (this.autoPlay) this.startAutoPlay();
	},
	
	startAutoPlay:function(){
		var obj = this;
		clearTimeout(obj.timer);
		obj.timer = setTimeout(function(){
			obj.nextSlide();
		},obj.switchTime);
	}
}