function empty(elementId)
{
	var element = document.getElementById(elementId);
	if(element)
	{
		if(element.value == '')
		{
			return true;
		}
		
		return false;
	}
	return true;
}

function emptyordefault(elementId, defaultvalue)
{
	var element = document.getElementById(elementId);
	if(element)
	{
		if(element.value == '' || element.value == defaultvalue)
		{
			return true;
		}
		
		return false;
	}
	return true;
}

function setfocus(element, defaultvalue)
{
	if(element)
	{
		if(element.value == defaultvalue)
		{
			element.value = '';
		}
	}
}

function setblur(element, defaultvalue)
{
	if(element)
	{
		if(element.value == '')
		{
			element.value = defaultvalue;
		}
	}
}

function reloadCaptcha()
{
	var t = new Date();
	$("#captcha_image").attr("src", "/captcha_image.php?c=" + t.getTime());
}

function loadRecept(receptId, allRecepts)
{
	for(var i=1; i<=allRecepts; i++)
	{
		document.getElementById('receptyimg_' + i).src= '/images/boxrecepty_gulicka_neaktivne.png';
		document.getElementById('boxrecepty_' + i).style.display = 'none';
	}
	
	document.getElementById('receptyimg_' + receptId).src= '/images/boxrecepty_gulicka_aktivne.png';
	document.getElementById('boxrecepty_' + receptId).style.display = 'block';
}

var scrollingUp = false;
function scrollBoxUp()
{
	if(boxSitesScroll == true && scrollingUp == false)
	{
		scrollingUp = true;
		var elm = $('#sitesboxslider');
		var checkPositions = $('#sitesboxslider').position();
		
		if(checkPositions.top > maxUp)
		{
			elm.animate
			(
					{
						top:'-=22px'
					},
					200,
					function()
					{
						if(boxSitesScroll == true)
						{
							scrollingUp = false;
							scrollBoxUp();
						}
					}
			);
		}
		else
		{
			scrollingUp = false;
		}
	}
	else
	{
		scrollingUp = false;
	}
	
}

var scrollingDown = false;
function scrollBoxDown()
{
	if(boxSitesScroll == true && scrollingDown == false)
	{
		scrollingDown = true;
		var elm = $('#sitesboxslider');
		var checkPositions = $('#sitesboxslider').position();
		
		if(checkPositions.top < maxDown)
		{
			elm.animate
			(
					{
						top:'+=22px'
					},
					200,
					function()
					{
						if(boxSitesScroll == true)
						{
							scrollingDown = false;
							scrollBoxDown();
						}
					}
			);
		}
		else
		{
			scrollingDown = false;
		}
	}
	else
	{
		scrollingDown = false;
	}
}


function animateImageBoxes(itemIndex, total)
{
	var mainImageElement = $('#homeboximagemain');
	var currentImageElement = $('#homeboximage_' + itemIndex);
	
	if(mainImageElement && currentImageElement)
	{
		//set the src & alt of first image
		mainImageElement.attr
		(
				{
					src: currentImageElement.attr('value'),
					alt: currentImageElement.attr('name')
				}
		);
		
		//fadein
		mainImageElement.animate
		(
				{
					//fade in
					opacity: 1
				},
				1000,
				function()
				{
					//stay
					mainImageElement.animate
					(
						{
							opacity: 1
						},
						2000,
						function()
						{
							//fade out
							mainImageElement.animate
							(
									{
										opacity: 0
									},
									1000,
									function()
									{
										itemIndex++;
										if(itemIndex>total)
										{
											itemIndex=1;
										}
										animateImageBoxes(itemIndex, total);
									}
							);
						}
					);
				}
		);
	}
}