var curPortal = 1;
var maxPortal = 4;
var fadeTick = 1;
var stopAuto = false;

function startPortal() {
	if(stopAuto) return;
	SwapPortal(1);
	setTimeout("startPortal()", 4000);
}

function SwapPortal(direction) {
	if(fadeTick!=1) return;
	fadePortal(direction);
}

function SwapPortalABS(portal) {
	if(fadeTick!=1) return;
	fadePortalABS(portal);
}

function ShowPortal(index) {
	for(i=1;i<=maxPortal;i++) {
		document.getElementById('portal'+i).style.opacity = '1';
		document.getElementById('portal'+i).style.display = 'none';
		if(document.getElementById('portalLink'+i)) { 
			document.getElementById('portalLink'+i).style.background = 'transparent';
			document.getElementById('portalLink'+i).style.color = 'blue';
		}
	}
	
	document.getElementById('portal'+index).style.display = 'block';
	if(document.getElementById('portalLink'+index)) {
		document.getElementById('portalLink'+index).style.background = '#005';
		document.getElementById('portalLink'+index).style.color = 'white';
	}	
}

function fadePortal(direction) {
	fadeTick-=.1
	if(fadeTick<0) { //done
		fadeTick=1;

		curPortal+=direction;
		if(curPortal>maxPortal) curPortal=1;
		if(curPortal<1) curPortal=maxPortal;
	
		ShowPortal(curPortal);
	} else { //keep going
		document.getElementById('portal'+curPortal).style.opacity = fadeTick;
		setTimeout("fadePortal("+direction+")",50);
	}
}

function fadePortalABS(portal) {
	fadeTick-=.1
	if(fadeTick<0) { //done
		fadeTick=1;
		curPortal=portal;
		ShowPortal(portal);
	} else { //keep going
		document.getElementById('portal'+curPortal).style.opacity = fadeTick;
		setTimeout("fadePortalABS("+portal+")",50);
	}
}

window.onload = function () {
	setTimeout("startPortal()", 4000);
}