var flg = 1;
var interID;
var apVer = navigator.appVersion;
var usrAgent = navigator.userAgent;
var FireFox;

function OS(){
	if(apVer.indexOf('Mac') != -1){
		return true;
	}else{
		return false;
	}
}

function Browser(){
	if(usrAgent.indexOf('Firefox') != -1){
		FireFox = true;
	}
	
}

function wrap1FadeIn(){
	flg = 1;
	$("#wrap1").hide();
	$("#wrap1").fadeIn(500,
		function(){
			setEffect();
    	});
	document.getElementById("wrap1").style.zIndex = 40;
	document.getElementById("wrap2").style.zIndex = 10;
	document.getElementById("wrap3").style.zIndex = 20;
	document.getElementById("wrap4").style.zIndex = 30;
}

function wrap2FadeIn(){
	flg = 2;
	$("#wrap2").hide();
	$("#wrap2").fadeIn(500,
		function(){
			setEffect();
    	});
	document.getElementById("wrap1").style.zIndex = 30;
	document.getElementById("wrap2").style.zIndex = 40;
	document.getElementById("wrap3").style.zIndex = 20;
	document.getElementById("wrap4").style.zIndex = 10;
}

function wrap3FadeIn(){
	flg = 3;
	$("#wrap3").hide();
	$("#wrap3").fadeIn(500,
		function(){
			setEffect();
    	});
	document.getElementById("wrap1").style.zIndex = 10;
	document.getElementById("wrap2").style.zIndex = 30;
	document.getElementById("wrap3").style.zIndex = 40;
	document.getElementById("wrap4").style.zIndex = 20;
}

function wrap4FadeIn(){
	flg = 4;
	$("#wrap4").hide();
	$("#wrap4").fadeIn(500,
		function(){
			setEffect();
    	});
	document.getElementById("wrap1").style.zIndex = 10;
	document.getElementById("wrap2").style.zIndex = 20;
	document.getElementById("wrap3").style.zIndex = 30;
	document.getElementById("wrap4").style.zIndex = 40;
}



function selectEffect(){
	switch(flg){
		case 1:
			wrap2FadeIn();
			break;
		case 2:
			wrap3FadeIn();
			break;
		case 3:
			wrap4FadeIn();
			break;
		case 4:
			wrap1FadeIn();
			break;
	}
	clearInterval(interID);
}

function setEffect(){
	Browser();
	if(screen.width > 1024){
		if(OS()){ // MAC
			if(FireFox){
				//alert("mac firefox");
			}else{
				//alert("mac no firefox");
				interID = setInterval("selectEffect()",5000);
			}
		}else{
			interID = setInterval("selectEffect()",5000);
		}
	}
}