/* マウスオーバー用 */
function changeImg(tagObj) {
	if(!tagObj.src.match(/_on\.gif/)) {
		tagObj.src=tagObj.src.slice(0,-4)+"_on.gif";
	} else {
		tagObj.src=tagObj.src.slice(0,-7)+".gif";
	}
}

window.onload = function(){
	(function(){
		var navi = document.getElementById("nav");
		var naviList = navi.getElementsByTagName("li");
		var currentPath = location.pathname;
		var pathType = (currentPath == "/" || currentPath == "/index.html")? "toppage" : "";
		for(var i=0;i<naviList.length;i++){
			var tagObj = naviList[i].getElementsByTagName("img")[0];
			var tagObjAnchor = naviList[i].getElementsByTagName("a")[0];
			if(i == 0 && pathType == "toppage"){
				tagObj.src = tagObj.src.slice(0,-4)+"_on.gif";
			}else if((i != 0 && !pathType) && location.href.match(tagObjAnchor.href)){
				tagObj.src = tagObj.src.slice(0,-4)+"_on.gif";
			}else{
				var onMouseUpFlg = (tagObjAnchor.getAttribute("target") && tagObjAnchor.getAttribute("target").match(/_blank/))? "" : "1";
				hoverNavi(tagObj, onMouseUpFlg);
			}
		}
	})();
	function hoverNavi(tagObj, onMouseUpFlg){
		new Image().src = tagObj.src.slice(0,-4)+"_on.gif";
		tagObj.onmouseover = function(){
			changeImg(this);
		}
		tagObj.onmouseout = function(){
			if(tagObj.src.match(/_on\.gif/)) {
				tagObj.src=tagObj.src.slice(0,-7)+".gif";
			}
		}
		if(onMouseUpFlg){
			tagObj.onmouseup = function(){
				if(this.src.match(/_on\.gif/)) {
					this.src = this.src.slice(0,-7)+".gif";
				}
			}
		}
	}
}