;(function($){

	var carousel = function(poster){
		var self = this;
		//保存单个旋转木马对象
		this.poster = poster;
		this.posteritemmain = poster.find("ul.poster-list");
		this.nextbtn = poster.find("div.poster-next-btn");
		this.prevbtn = poster.find("div.poster-prev-btn");
		this.posteritems = poster.find("li.poster-item");
		if( this.posteritems.size()%2 == 0 ){
			this.posteritemmain.append( this.posteritems.eq(0).clone() );
			this.posteritems = this.posteritemmain.children();
		};
		this.posterfirstitem = this.posteritems.first();
		this.posterlastitem = this.posteritems.last();
		this.rotateflag = true;
		//默认配置参数
		this.setting = {
			"width" : 1000,			//幻灯片的宽度
			"height" : 450,			//幻灯片的高度
			"posterwidth" : 600,	//幻灯片第一帧的宽度
			"posterheight" : 450,	//幻灯片第一帧的高度
			"scale" : 0.9,			//记录显示比例关系
			"speed" : 500,
			"autoplay" : false,
			"delay" : 5000,
			"verticalalign" : "middle" //top bottom
		};
		$.extend( this.setting,this.getsetting() );
		
		//设置配置参数值
		this.setsettingvalue();
		//初始化幻灯片位置
		this.setposterpos();
		//左旋转按钮
		this.nextbtn.click(function(){
			if(self.rotateflag){
				self.rotateflag = false;
				self.carouserotate("left");
			};
		});
		//右旋转按钮
		this.prevbtn.click(function(){
			if(self.rotateflag){
				self.rotateflag = false;
				self.carouserotate("right");
			};
		});
		//是否开启自动播放
		if(this.setting.autoplay){
			this.autoplay();
			this.poster.hover( function(){
				//self.timer是setinterval的种子
				window.clearinterval(self.timer);
			}, function(){
				self.autoplay();
			});			
		};
	};
	carousel.prototype = {
		autoplay:function(){
			var self = this;
			this.timer = window.setinterval( function(){
				self.nextbtn.click();
			}, this.setting.delay );
		},

		//旋转
		carouserotate:function(dir){
			var _this_  = this;
			var zindexarr = [];
			//左旋转
			if(dir === "left"){
				this.posteritems.each(function(){
					var self = $(this),
						prev = self.prev().get(0)?self.prev():_this_.posterlastitem,
						width = prev.width(),
						height =prev.height(),
						opacity = prev.css("opacity"),
						left = prev.css("left"),
						top = prev.css("top"),
						zindex = prev.css("zindex");

					zindexarr.push(zindex);
					self.animate({
						width :width,
						height :height,
					  //zindex :zindex,
					    opacity :opacity,
					    left :left,
					    top :top
					},_this_.setting.speed,function(){
						_this_.rotateflag = true;
					});
				});
				//zindex需要单独保存再设置，防止循环时候设置再取的时候值永远是最后一个的zindex
				this.posteritems.each(function(i){
					$(this).css("zindex",zindexarr[i]);
				});
			}else if(dir === "right"){//右旋转
				this.posteritems .each(function(){
					var self = $(this),
						next = self.next().get(0)?self.next():_this_.posterfirstitem,
						width = next.width(),
						height =next.height(),
						opacity = next.css("opacity"),
						left = next.css("left"),
						top = next.css("top"),
						zindex = next.css("zindex");

					zindexarr.push(zindex);					
					self.animate({
						width :width,
						height :height,
					  //zindex :zindex,
					    opacity :opacity,
					    left :left,
					    top :top
					},_this_.setting.speed,function(){
						_this_.rotateflag = true;
					});	
				});
				//zindex需要单独保存再设置，防止循环时候设置再取的时候值永远是最后一个的zindex
				this.posteritems.each(function(i){
					$(this).css("zindex",zindexarr[i]);
				});
			};
		},
		//设置剩余的帧的位置关系
		setposterpos:function(){
			var self = this,
				sliceitems = this.posteritems.slice(1),
				slicesize = sliceitems.size()/2,
				rightslice = sliceitems.slice(0,slicesize),
				//存在图片奇偶数问题
				level = math.floor(this.posteritems.size()/2),
				leftslice = sliceitems.slice(slicesize);
			
			//设置右边帧的位置关系和宽度高度top
			var firstleft = (this.setting.width - this.setting.posterwidth)/2;
			var rw = this.setting.posterwidth,
				fixoffsetleft = firstleft + rw,
				rh = this.setting.posterheight,
				gap = ((this.setting.width - this.setting.posterwidth)/2)/level;
			
			//设置右边位置关系
			rightslice.each(function(i){
				level--;
				rw = rw * self.setting.scale;
				rh = rh * self.setting.scale;
				var j = i;
				$(this).css({
					zindex :level,
					width :rw,
					height :rh,
					opacity :1/(++j),
					left :fixoffsetleft+(++i)*gap - rw,
					top :self.setverticalalign(rh)
				});
			});

			//设置左边的位置关系
			var lw = rightslice.last().width(),
				lh  =rightslice.last().height(),
				oloop = math.floor(this.posteritems.size()/2);
			leftslice.each(function(i){
				$(this).css({
					zindex:i,
					width:lw,
					height:lh,
					opacity:1/oloop,
					left:i*gap,
					top:self.setverticalalign(lh)
				});
				lw = lw/self.setting.scale;
				lh = lh/self.setting.scale;
				oloop--;
			});
		},
	
		//设置垂直排列对齐
		setverticalalign:function(height){
			var verticaltype  = this.setting.verticalalign,
				top = 0;
			if(verticaltype === "middle"){
				top = (this.setting.height-height)/2;
			}else if(verticaltype === "top"){
				top = 0;
			}else if(verticaltype === "bottom"){
				top = this.setting.height-height;
			}else{
				top = (this.setting.height-height)/2;
			};
			return top;
		},

		//设置配置参数值去控制基本的宽度高度。。。
		setsettingvalue:function(){
			this.poster.css({
				width:this.setting.width,
				height:this.setting.height
			});
			this.posteritemmain.css({
				width:this.setting.width,
				height:this.setting.height
			});
			//计算上下切换按钮的宽度
			var w = (this.setting.width-this.setting.posterwidth)/2;
			//设置切换按钮的宽高，层级关系
			this.nextbtn.css({
				width:w,
				height:this.setting.height,
				zindex:math.ceil(this.posteritems.size()/2)
			});
			this.prevbtn.css({
				width:w,
				height:this.setting.height,
				zindex:math.ceil(this.posteritems.size()/2)
			});			
			this.posterfirstitem.css({
				width:this.setting.posterwidth,
				height:this.setting.posterheight,
				left:w,
				top:0,
				zindex:math.floor(this.posteritems.size()/2)
			});
		},

		//获取人工配置参数
		getsetting:function(){			
			var setting = this.poster.attr("data-setting");
			if(setting && setting != ""){
				return $.parsejson(setting);
			}else{
				return {};
			};
		}	
	};

	carousel.init = function(posters){
		var _this_ = this;
		posters.each(function(){
			// console.log("halo louis;")
			new  _this_($(this));
		});
	};

	//挂载到window下
	window.carousel = carousel;

})(jquery);