var confScreenWidth = 1280;
var keyScreenWidthCookie = 'ScreenWidth';
var cookieScreenWidth = readCookie(keyScreenWidthCookie);
var screenWidth = screen.width;

//alert('screenWidth: ' + screenWidth + '\n' + 'cookieScreenWidth: ' + cookieScreenWidth);
if(typeof(screenWidth) != 'undefined')
{
	if(cookieScreenWidth == null)
	{
		document.cookie = keyScreenWidthCookie + '=' + screenWidth;
		//la pagina php sta scrivendo per una SceenWidth<=1280 che e' il default
		//alert('null');
		if(screenWidth > confScreenWidth)
		{
			location.reload(true);
		}
	}
	else
	{
		if(screenWidth != cookieScreenWidth)
		{
			document.cookie = keyScreenWidthCookie + '=' + screenWidth;
			if(
					(screenWidth <= confScreenWidth && cookieScreenWidth > confScreenWidth)
					||
					(screenWidth > confScreenWidth && cookieScreenWidth <= confScreenWidth)
			  )
			{
				location.reload(true);
			}
		}
	}
}

function readCookie(key)
{
	var allcookie = document.cookie;
	var pos = allcookie.indexOf(key + '=');
	if(pos != -1)
	{
		var start = pos + key.lenght + 1;
		var end = allcookie.indexOf(';', start);
		if(end == -1)
			end = allcookie.length;
		var value = allcookie.substring(start, end);
		value = unescape(value)
		return value;
	}
	return null;
}