var browserVer = "";
var opacity = 0;
var timer;
var layerId1, layerId2, tabId1, tabId2;
var step = 6, spacing = 1;

function el(id){
	return document.getElementById(id);
}

function init(){
	whichBrowser();
	var locaHref = location.href;
	var paramArr = locaHref.split("#");
	el("loading-clew").style.display = "none";
	if (paramArr[1])
	{
		param = paramArr[1].split("?")[0];
		if ( browserVer == 1)
		{
			el(param).filters.alpha.opacity = 100;
		}
		else
		{
			el(param).style.opacity = 1;
		}
		el(param).style.display = "block";
		el(param).style.height = el(param).offsetHeight;
		layerId1 = param;
	}
	else
	{
		var layers = document.getElementsByClassName("unit");
		param = layers[0];
		if ( browserVer == 1)
		{
			param.filters.alpha.opacity = 100;
		}
		else
		{
			param.style.opacity = 1;
		}
		param.style.display = "block";
		layers[0].style.height = layers[0].offsetHeight;
		layerId1 = param.id;
	}
	tabId1 = layerId1.split("_content",1);
	el(tabId1).className = "select";
	el("nav").style.visibility = "visible";;
	opacity = 100;
}

document.getElementsByClassName = function(eleClassName)
{
	var getEleClass = [];//定义一个数组
	var myclass = new RegExp("\\b"+eleClassName+"\\b");//创建一个正则表达式对像
	var elem = this.getElementsByTagName("*");//获取文档里所有的元素
	for(var h=0; h<elem.length; h++)
	{
		var classes = elem[h].className;//获取class对像
		if (myclass.test(classes)) getEleClass.push(elem[h]);//正则比较，取到想要的CLASS对像
	}
	return getEleClass;//返回数组
}

function whichBrowser()
{
    if ( navigator.userAgent.indexOf("MSIE") >= 0 )
	{
		browserVer = 1;
	}else{
		browserVer = 2;
	}
}

function startCtlOpacity( layerId2 ){
	if ( layerId1 == undefined || layerId1 == layerId2 || opacity != 100 ) {
		return;
	}else{
		tabId2 = layerId2.split("_content",1);
		el(tabId1).className = "unselect";
		el(tabId2).className = "select";
		timer = setInterval( function(){ hideLayer( layerId1, layerId2, step ) },spacing );
	}
}

function hideLayer( layerId1, layerId2, step ){
	if ( opacity == 0 ) {
		el(layerId1).style.display = "none";
		el(layerId2).style.display = "block";
		el(layerId2).style.height = el(layerId2).offsetHeight;
		stopTimer(layerId2);
	}else if ( opacity < 0 ) {
		if ( browserVer == 1 ) {
			el(layerId1).filters.alpha.opacity = 0;
		}else{
			el(layerId1).style.opacity = 0;
		}
		opacity = 0;
		el(layerId1).style.display = "none";
		el(layerId2).style.display = "block";
		el(layerId2).style.height = el(layerId2).offsetHeight;
		stopTimer(layerId2);
	}else{
		opacity = opacity - step;
		if ( browserVer == 1 ){
			el(layerId1).filters.alpha.opacity = opacity;
		}else{
			el(layerId1).style.opacity = opacity / 100;
		}
	}
}

function showLayer( layerId2 ){
	if ( opacity == 100 ) {
		stopTimer(layerId2);
	}else if ( opacity > 100 ) {
		if ( browserVer == 1 ) {
			el(layerId2).filters.alpha.opacity = 100;
		}else{
			el(layerId2).style.opacity = 1;
		}
		stopTimer(layerId2);
	}else{
		opacity = opacity + step;
		if ( browserVer == 1 ){
			el(layerId2).filters.alpha.opacity = opacity;
		}else{
			el(layerId2).style.opacity = opacity / 100;
		}
	}
}

function stopTimer( layerId2 ){
	if (opacity == 0)
	{
		clearInterval(timer);
		timer = setInterval(function(){ showLayer( layerId2 ) },spacing)
	}
	else
	{
		clearInterval( timer );
		layerId1 = layerId2;
		tabId1 = tabId2;
		opacity = 100;
	}
}

window.onload = init;