var vidState=new Array();

var myBrowser = null; 
if(document.all) { 
  myBrowser = "IE"; 
} else if(document.layers) { 
  myBrowser = "NN"; 
} else if(document.getElementById) { 
  myBrowser = "DOM"; 
} 

function send2vids(a)
{
	document.F.ref.value=a;
	toggleLogin('on');
}

function toggleLogin(state)
{
	opera=0;
	if(document.all && (navigator.userAgent.indexOf("Opera")>=0))
		opera=1;
	layer=document.getElementById('loginbox');
	if(state=='off')
	{
		layer.style.visibility='hidden';
		layer.style.zIndex=-1;
		toggleLayer('on','VID');
		if(opera)
		{
			toggleLayer('on','roller1');
			toggleLayer('on','roller2');
			toggleLayer('on','roller3');
			toggleLayer('on','roller4');
		}
		if((lf=document.getElementById('loginFailed')))
			lf.innerHTML="";
	}
	else
	{
		toggleLayer('off','VID');
		if(opera)
		{
			toggleLayer('off','roller1');
			toggleLayer('off','roller2');
			toggleLayer('off','roller3');
			toggleLayer('off','roller4');
		}
		layer.style.visibility='visible';
		layer.style.zIndex=8;
		centerLayer('loginbox');
	}
}

function toggleLayer(state,name)
{
	if(state=='on')
	{
		if((vid=document.getElementById(name)))
		{
			if(vidState[name]=="hidden")
			{
				vid.style.visibility='visible';
				vidState[name]="visible";
			}
		}
	}
	else
	{
		if((vid=document.getElementById(name)))
		{
			if(vid.style.visibility!="hidden")
			{
				vid.style.visibility='hidden';
				vidState[name]="hidden";
			}
		}
	}
}


// gets window height 
function getWindowHeight(thisWindow) { 
  if(myBrowser == "NN" || myBrowser == "DOM") { 
    return(thisWindow.innerHeight); 
  } else if(myBrowser == "IE") { 
    return(thisWindow.document.body.clientHeight); 
  } 
} 

// gets window width 
function getWindowWidth(thisWindow) { 
  if(myBrowser == "NN" || myBrowser == "DOM") { 
    return(thisWindow.innerWidth); 
  } else if(myBrowser == "IE") { 
    return(thisWindow.document.body.clientWidth); 
  } 
} 

// gets a layer's height 
function getLayerHeight(thisLayer) { 
  if(myBrowser == "NN") { 
    return(thisLayer.document.height); 
  } else if(myBrowser == "IE" || myBrowser == "DOM") { 
    return(thisLayer.offsetHeight); 
  } 
} 

// gets a layer's width 
function getLayerWidth(thisLayer) { 
  if(myBrowser == "NN") { 
    return(thisLayer.document.width); 
  } else if(myBrowser == "IE" || myBrowser == "DOM") { 
    return(thisLayer.offsetWidth); 
  } 
} 

// moveTo-functionality 
function moveLayerTo(thisLayer, xPos, yPos) { 
  if(myBrowser == "NN") { 
    thisLayer.moveTo(xPos, yPos); 
  } else if(myBrowser == "IE" || myBrowser == "DOM") { 
    thisLayer.style.left = xPos + "px"; 
    thisLayer.style.top = yPos + "px"; 
  } 
} 

// logic to center a layer with ID 
function centerLayer(thisID) { 
  var winWidth, winHeight, myWidth, myHeight, myLayer, xPos, yPos; 
  winWidth = getWindowWidth(self); 
  winHeight = getWindowHeight(self); 

  if(myBrowser == "NN") { 
    myLayer = document.layers[thisID]; 
  } else if(myBrowser == "IE") { 
    myLayer = document.all[thisID]; 
  } else if(myBrowser == "DOM") { 
    myLayer = document.getElementById(thisID); 
  } 
  myWidth = getLayerWidth(myLayer); 
  myHeight = getLayerHeight(myLayer); 
  xPos = Math.floor((winWidth-myWidth)/2);
  yPos = Math.floor((winHeight-myHeight)/2) + document.body.scrollTop; 
  moveLayerTo(myLayer, xPos, yPos); 
}