var navigatorUA = navigator.userAgent.toLowerCase();
var isOpera = navigatorUA.indexOf('opera') >= 0? true: false;
var isIE = navigatorUA.indexOf('msie') >= 0 && !isOpera? true: false;
var isSafari = navigatorUA.indexOf('safari') >= 0 || navigatorUA.indexOf('khtml') >= 0? true: false;

function rollOver(){
	
	var imgRenban=0;
	var imgs = document.getElementsByTagName('img');
	for (i=0 ; i < imgs.length; i++ ) {
		var img = imgs[i];
		if(img.className.indexOf('rollover') >= 0){
			try {
				if(img.id == ""){
					img.id = "rollover_" + imgRenban;
					//alert(img.id);
					imgRenban++;
				}
				if(img.addEventListener){
					img.addEventListener('mouseover',over, false);
					img.addEventListener('mouseout', out, false);
					img.addEventListener('mousedown', down, false);
					img.addEventListener('click', click, false);
				}else if(img.attachEvent){
					img.attachEvent('onmouseover', over);
					img.attachEvent('onmouseout', out);
					img.attachEvent('onmousedown', down);
					img.attachEvent('onclick', click);
				}
			} catch(err) {
				img = null;
			}
			
		}
	}
}

function getNavi(){
  	navigatorUA = navigator.userAgent.toLowerCase();
 	isOpera = navigatorUA.indexOf('opera') >= 0? true: false;
 	isIE = navigatorUA.indexOf('msie') >= 0 && !isOpera? true: false;
 	isSafari = navigatorUA.indexOf('safari') >= 0 || navigatorUA.indexOf('khtml') >= 0? true: false;
}

function over() {

	var id = "";
	if(isIE){
		id = event.srcElement.id;
	}else{
		id = this.id;
	}
		
	if(id != ""){
		var target = document.getElementById(id);
		if(target != ""){
			var baseImg = target.src;
			if(baseImg.indexOf('_c.gif') >= 0){
				baseImg=baseImg.replace("_c.gif",".gif");
			}
			var newImg = baseImg.replace(".gif","_o.gif");
			target.src = newImg;
		}
	}
}

function out() {
	
	var id = "";
	if(isIE){
		id = event.srcElement.id;
	}else{
		id = this.id;
	}
	
	if(id != ""){
		var target = document.getElementById(id);
		if(target != ""){
			var baseImg = target.src;
			if(baseImg.indexOf('_c.gif') >= 0){
				baseImg=baseImg.replace("_c.gif",".gif");
			}
			var newImg = baseImg.replace("_o.gif",".gif");
			target.src = newImg;
		}
	}
}

function down() {

	var id = "";
	if(isIE){
		id = event.srcElement.id;
	}else{
		id = this.id;
	}
	
	if(id != ""){
		var target = document.getElementById(id);
		if(target != ""){
			var baseImg = target.src;
			var newImg = baseImg.replace("_o.gif","_c.gif");
			if(isImg(newImg)){
				target.src = newImg;
			}
		}
	}
	
}

function isImg(imgUrl){
	var img = new Image();
	img.src = imgUrl;
	return img.height > 0;
}


function click(){

	var imgs = document.getElementsByTagName('img');
	for (i=0 ; i < imgs.length; i++ ) {
		var img = imgs[i];
		if(img.className.indexOf('rollover') >= 0){
			if(img.addEventListener){
				img.removeEventListener('mouseover',over, false);
				img.removeEventListener('mouseout', out, false);
				img.removeEventListener('mousedown', down, false);
			}else if(img.attachEvent){
				img.detachEvent('onmouseover', over);
				img.detachEvent('onmouseout', out);
				img.detachEvent('onmousedown', down);
			}
		}	
	}
	
}

if(isIE){
	window.attachEvent("onload" , rollOver);
}else{
	window.addEventListener("load" , rollOver , true);
}