//图片、文字平滑滚动（支持横向、纵向滚动，是否循环，单条或多条记录，可设置每次次滚动条数、速度、间隔、自动开始滚动等）
//需要jQuery支持 Built for jQuery library，written by Siyue 2009.12
(function($) {
	$.fn.slider = function(options){
	    //默认属性
		var defaults = {			
			prevId: 		'prevBtn',
			prevText: 		'Previous',
			nextId: 		'nextBtn',	
			nextText: 		'Next',
			controlsFade:	true,//不循环情况下是否隐藏按钮
			firstId: 		'firstBtn',
			firstText: 		'First',
			firstShow:		false,
			lastId: 		'lastBtn',	
			lastText: 		'Last',
			lastShow:		false,				
			vertical:		false,//方向，默认横向滚动
			speed: 			800,//速度
			auto:			true,//是否自动滚动
			pause:			2000,//间隔时间
			mouseoverstop:       false,//鼠标悬浮是否停止
			continuous:		true,//是否循环
			count:  1,//滚动条数,默认每次滚动一条
			quantity: 		1//显示的数量			
		}; 
		var options = $.extend(defaults, options);  

		this.each(function() {  
			var obj = $(this); 				
			var s = $("li", obj).length;
			var w = $("li", obj).width(); 
			var h = $("li", obj).height(); 
			
			var suitcount=(options.quantity>=s)?s:options.quantity;
			//obj.width( $("ul", obj).width()); //注释掉表示容器固定大小，不以li的数目而自动伸展，若要自适应宽度请删除注释
			obj.height($("ul", obj).height());
			obj.css("overflow","hidden");
			
			var ts = options.vertical? (parseInt(s/suitcount)-((s%suitcount>0)?0:1)):(s-suitcount);
			var t = 0;

			if(!options.vertical) 
			{
				$("ul", obj).css('width',s*w);	//s个li的宽度相加＝ul的宽度，高度一样
				$("li", obj).css('float','left');
			}
			else
			{
				$("ul", obj).css('width',suitcount*w)	
			}

			$("#"+options.nextId).click(function(){
													
				animate("next",true);
			});
			$("#"+options.prevId).click(function(){
													
				animate("prev",true);				
			});	
			$("#"+options.firstId).click(function(){		
				animate("first",true);
			});				
			$("#"+options.lastId).click(function(){		
				animate("last",true);				
			});		
			
			function animate(dir,clicked){
				var ot = t;				
				switch(dir){
					case "next":
						t = (ot>=ts) ? (options.continuous ? 0 : ts) : (ot+options.count>ts?ts:t+options.count);						
						break; 
					case "prev":
						t = (t<=0) ? (options.continuous ? ts : 0) : (ot-options.count<0?0:t-options.count);
						break; 
					case "first":
						t = 0;
						break; 
					case "last":
						t = ts;
						break; 
					default:
						break; 
				};	
				
				var diff = Math.abs(ot-t);
				var speed=diff*options.speed;						
				if(!options.vertical) {
					p = (t*w*-1);
					$("ul",obj).animate(
						{ marginLeft: p }, 
						(p==0)?1500:speed
					);				
				} else {
					p = (t*h*-1);
					$("ul",obj).animate(
						{ marginTop: p }, 
						speed
					);					
				};
				
				if(!options.continuous && options.controlsFade){					
					if(t==ts){
						$("#"+options.nextId).hide();
						$("#"+options.lastId).hide();
					} else {
						$("#"+options.nextId).show();
						$("#"+options.lastId).show();					
					};
					if(t==0){
						$("#"+options.prevId).hide();
						$("#"+options.firstId).hide();
					} else {
						$("#"+options.prevId).show();
						$("#"+options.firstId).show();
					};					
				};				
				
				if(clicked) 
				{   
				    clearTimeout(timeout);      //如点击了按钮则将停顿时间重置
				    timeout = setTimeout(function(){
						animate("next",false);
					},diff*options.speed+options.pause);
				}
				
				if(options.auto && dir=="next" && !clicked){;
					timeout = setTimeout(function(){
						animate("next",false);
					},diff*options.speed+options.pause);
				};
				
			};
			//自动滚动
			var timeout;
			if(options.auto){;
				timeout = setTimeout(function(){
					animate("next",false);
				},options.pause);
			};		
			
			//鼠标悬浮停止滚动
			if(options.mouseoverstop)
			{
			    $("ul",obj).hover(
                    function(){clearTimeout(timeout);},
                    function(){timeout = setTimeout(function(){
					    animate("next",false);
				    },options.pause);});
		    }

			if(!options.continuous && options.controlsFade){					
				$("#"+options.prevId).hide();
				$("#"+options.firstId).hide();				
			};				
			
		});
	  
	};

})(jQuery);