/*
 * 	Arquivo alterado dia 25/08/2011 - por Alexandre
 *  Foi editado para que o slider de o aspecto de carrossel, para que seja sempre continuo independente do numero de LI que esta exibindo na div.	
 *
 * 	Easy Slider 1.7 - jQuery plugin
 *	written by Alen Grakalic	
 *	http://cssglobe.com/post/4004/easy-slider-15-the-easiest-jquery-plugin-for-sliding
 *
 *	Copyright (c) 2009 Alen Grakalic (http://cssglobe.com)
 *	Dual licensed under the MIT (MIT-LICENSE.txt)
 *	and GPL (GPL-LICENSE.txt) licenses.
 *
 *	Built for jQuery library
 *	http://jquery.com
 *
 */
 
/*
 *	markup example for $("#slider").easySlider();
 *	
 * 	<div id="slider">
 *		<ul>
 *			<li><img src="images/01.jpg" alt="" /></li>
 *			<li><img src="images/02.jpg" alt="" /></li>
 *			<li><img src="images/03.jpg" alt="" /></li>
 *			<li><img src="images/04.jpg" alt="" /></li>
 *			<li><img src="images/05.jpg" alt="" /></li>
 *		</ul>
 *	</div>
 *
 */

(function($) {

	$.fn.easySlider = function(options){
	  
		// default configuration properties
		var defaults = {			
			prevId: 		'prevBtn',
			prevText: 		'Previous',
			nextId: 		'nextBtn',	
			nextText: 		'Next',
			controlsShow:	true,
			controlsBefore:	'',
			controlsAfter:	'',	
			controlsFade:	true,
			firstId: 		'firstBtn',
			firstText: 		'First',
			firstShow:		false,
			lastId: 		'lastBtn',	
			lastText: 		'Last',
			lastShow:		false,				
			vertical:		false,
			speed: 			800,
			auto:			false,
			pause:			2000,
			continuous:		false, 
			numeric: 		false,
			numericId: 		'controls',
			aumentar:		false, //novo atributo, criado em 25/08/2011 por Alexandre
			carregarImagem:		false, //novo atributo, criado em 29/08/2011 por Alexandre
			funcaoPosterior: false //novo atributo, criado em 03/10/2011 por Alexandre
		}; 
		
		var options = $.extend(defaults, options);  
				
		this.each(function() {  
			var obj = $(this); 				
			var s = $("li", obj).length;
			var w = $("li", obj).width(); 
			var h = $("li", obj).height();
			var qtClone = Math.ceil($("ul", obj).width()/w);
			var clickable = true;
			obj.width(w); 
			obj.height(h); 
			obj.css("overflow","hidden");
			var ts = s-1;
			var t = 0;
			$("ul", obj).css('width',s*w);			
			
			if(options.continuous){
				$("ul", obj).prepend($("ul li:last-child", obj).clone().css("margin-left","-"+ w +"px"));
				for(x=2; x<=(qtClone+1); x++){
				$("ul", obj).append($("ul li:nth-child("+x+")", obj).clone());
				}
				$("ul", obj).css('width',(s+qtClone)*w);
			};				
			
			if(!options.vertical) $("li", obj).css('float','left');
								
			if(options.controlsShow){
				var html = options.controlsBefore;				
				if(options.numeric){
					html += '<ol id="'+ options.numericId +'"></ol>';
				} else {
					if(!document.getElementById(options.prevId)||!document.getElementById(options.nextId)){
						if(options.firstShow) html += '<span id="'+ options.firstId +'"><a href=\"javascript:void(0);\">'+ options.firstText +'</a></span>';
						html += ' <span id="'+ options.prevId +'"><a href=\"javascript:void(0);\">'+ options.prevText +'</a></span>';
						html += ' <span id="'+ options.nextId +'"><a href=\"javascript:void(0);\">'+ options.nextText +'</a></span>';
						if(options.lastShow) html += ' <span id="'+ options.lastId +'"><a href=\"javascript:void(0);\">'+ options.lastText +'</a></span>';	
					}
				};
				
				html += options.controlsAfter;						
				$(obj).after(html);										
			};
			
			if(options.numeric){									
				for(var i=0;i<s;i++){						
					$(document.createElement("li"))
						.attr('id',options.numericId + (i+1))
						.html('<a rel='+ i +' href=\"javascript:void(0);\">'+ (i+1) +'</a>')
						.appendTo($("#"+ options.numericId))
						.click(function(){							
							animate($("a",$(this)).attr('rel'),true);
						}); 												
				};							
			} else {
				$("a","#"+options.nextId).click(function(){		
					animate("next",true);
				});
				$("a","#"+options.prevId).click(function(){		
					animate("prev",true);				
				});	
				$("a","#"+options.firstId).click(function(){		
					animate("first",true);
				});				
				$("a","#"+options.lastId).click(function(){		
					animate("last",true);				
				});				
			};
			
			function setCurrent(i){
				i = parseInt(i)+1;
				$("li", "#" + options.numericId).removeClass("current");
				$("li#" + options.numericId + i).addClass("current");
			};
			
			function adjust(){
				if(t>ts) t=0;		
				if(t<0) t=ts;	
				if(!options.vertical) {
					$("ul",obj).css("margin-left",(t*w*-1));
				} else {
					$("ul",obj).css("margin-left",(t*w*-1));
				}
				clickable = true;
				if(options.numeric) setCurrent(t);
			};
			
			function animate(dir,clicked){
				if (clickable){
					clickable = false;
					var ot = t;				
					switch(dir){
						case "next":
							t = (ot>=ts) ? (options.continuous ? t+1 : ts) : t+1;						
							break; 
						case "prev":
							t = (t<=0) ? (options.continuous ? t-1 : 0) : t-1;
							break; 
						case "first":
							t = 0;
							break; 
						case "last":
							t = ts;
							break; 
						default:
							t = dir;
							break; 
					};	
					var nSlider = t>ts?0:t;
						nSlider = nSlider<0?ts:nSlider;
					window.nSlider = nSlider;
					var diff = Math.abs(ot-t);
					var speed = diff*options.speed;						
					if(!options.vertical) {
						p = (t*w*-1);
						$("ul",obj).animate(
							{ marginLeft: p }, 
							{ queue:false, duration:speed, complete:adjust },
							options.carregarImagem?loadImagem(options.carregarImagem, nSlider, dir):null
						);
					} else {
						p = (t*h*-1);
						$("ul",obj).animate(
							{ marginTop: p }, 
							{ queue:false, duration:speed, complete:adjust }
						);					
					};
					
					if(options.funcaoPosterior){
						var eScript = document.createElement('script');
						eScript.innerHTML = options.funcaoPosterior;
						document.getElementsByTagName('head').item(0).appendChild(eScript);
					}
					
					if(!options.continuous && options.controlsFade){					
						if(t==ts){
							$("a","#"+options.nextId).hide();
							$("a","#"+options.lastId).hide();
						} else {
							$("a","#"+options.nextId).show();
							$("a","#"+options.lastId).show();					
						};
						if(t==0){
							$("a","#"+options.prevId).hide();
							$("a","#"+options.firstId).hide();
						} else {
							$("a","#"+options.prevId).show();
							$("a","#"+options.firstId).show();
						};					
					};
					
					//criado dia 25/08/2011 - Alexandre
					if(options.aumentar){
						
					};
					
					if(clicked) clearTimeout(timeout);
					if(options.auto && dir=="next" && !clicked){;
						timeout = setTimeout(function(){
							animate("next",false);
						},diff*options.speed+options.pause);
					};
			
				};
				
			};
			// init
			var timeout;
			if(options.auto){;
				timeout = setTimeout(function(){
					animate("next",false);
				},options.pause);
			};		
			
			if(options.numeric) setCurrent(0);
		
			if(!options.continuous && options.controlsFade){					
				$("a","#"+options.prevId).hide();
				$("a","#"+options.firstId).hide();				
			};				
			
		});
	  
	};

})(jQuery);

function prepareMouseOverImage(image, originalURL)
{
	if(navigator.appName.indexOf('Internet Explorer')<0){
		image.mouseOverImage=originalURL;
		image.onload=function(){return true;};
		image.normalImage=grayscale(image, false);
	
		image.onmouseover=function()
		{
			this.src=this.mouseOverImage;
		}
	
		image.onmouseout=function()
		{
			this.src=this.normalImage;
		}
		image.src=image.normalImage;
	}
}


function grayscale(image, bPlaceImage)
{
  var myCanvas=document.createElement("canvas");
  var myCanvasContext=myCanvas.getContext("2d");

  var imgWidth=image.width;
  var imgHeight=image.height;
  // You'll get some string error if you fail to specify the dimensions
  myCanvas.width= imgWidth;
  myCanvas.height=imgHeight;
//  alert(imgWidth);
  myCanvasContext.drawImage(image,0,0);

  // The getImageData() function cannot be called if the image is not from the same domain.
  // You'll get security error
  var imageData=myCanvasContext.getImageData(0,0, imgWidth, imgHeight);
  for (i=0; i<imageData.height; i++)
  {
    for (j=0; j<imageData.width; j++)
    {
	  var index=(i*4)*imageData.width+(j*4);
	  var red=imageData.data[index];
	  var green=imageData.data[index+1];
	  var blue=imageData.data[index+2];
	  var alpha=imageData.data[index+3];
	  var average=(red+green+blue)/3;
   	  imageData.data[index]=average;
   	  imageData.data[index+1]=average;
   	  imageData.data[index+2]=average;
   	  imageData.data[index+3]=alpha;
	}
  }
  myCanvasContext.putImageData(imageData,0,0,0,0, imageData.width, imageData.height);
 // myCanvasContext.drawIMage(imageData,0,0);//,0,0, imageData.width, imageData.height);

  if (bPlaceImage)
  {
	  var myDiv=document.createElement("div");
	  myDiv.appendChild(myCanvas);
	  image.parentNode.appendChild(myCanvas);//, image);
  }
  return myCanvas.toDataURL();
}