// JavaScript Document

var loginElement;
var loginTop;
var repeater;
var interval;
var loginVisible;
var frameNumber;
var bodyElement;
var fontControl;
var fontEmbiggened;

window.onload = function()
{
	loginElement = document.getElementById("login");
	loginTop = -75;
	loginElement.style.top = numberToPixelSize(loginTop);
	loginVisible = false;
	frameNumber = 0;
	interval = 1000/24;
	bodyElement = document.getElementsByTagName("body").item(0);
	fontControl = document.getElementById("fontcontrol").getElementsByTagName("img").item(0);
	fontEmbiggened = false;
};

function toggleLogin()
{
	document.getElementById("txtLogin").focus();
	repeater = setInterval(moveLogin,interval);
}

function moveLogin()
{
	frameNumber += 1;
	if(loginVisible)
	{
		if (pixelSizeToNumber(loginElement.style.top) > loginTop)
		{
			loginElement.style.top = numberToPixelSize(Math.ceil(easeOut(frameNumber,0,loginTop,12)));
		}
		else
		{
			loginVisible = false;
			frameNumber = 0;
			clearInterval(repeater);
		}
	}
	else
	{
		if (pixelSizeToNumber(loginElement.style.top) < 0)
		{
			loginElement.style.top = numberToPixelSize(Math.floor(easeIn(frameNumber,loginTop,Math.abs(loginTop),12)));
		}
		else
		{
			loginVisible = true;
			frameNumber = 0;
			clearInterval(repeater);
		}
	}
}

function easeIn (t, b, c, d) {
	return -c * Math.cos(t/d * (Math.PI/2)) + c + b;
}
function easeOut (t, b, c, d) {
	return c * Math.sin(t/d * (Math.PI/2)) + b;
}
function easeInOut (t, b, c, d) {
	return -c/2 * (Math.cos(Math.PI*t/d) - 1) + b;
}

function pixelSizeToNumber(pixelSize)
{
	return pixelSize.substring(0,(pixelSize.length-2)).valueOf();
}

function numberToPixelSize(size)
{
	return size + "px"
}

function toggleFontSize()
{
	if (!fontEmbiggened)
	{
		bodyElement.style.fontSize = numberToPixelSize(14);
		fontControl.title = "Decrease font size";
		fontControl.alt = "Decrease font size";
		fontControl.src = "../images/font-decrease.gif";
		fontEmbiggened = true;
	}
	else
	{
		bodyElement.style.fontSize = numberToPixelSize(11);
		fontControl.title = "Increase font size";
		fontControl.alt = "Increase font size";
		fontControl.src = "../images/font-increase.gif";
		fontEmbiggened = false;
	}
	return false; // do not follow link
}

function openimage(img)
{
		window.open('../general/showimage.asp?img=' + img,'','width=770,height=600');
}