function show_hide(id) {
	var el = document.getElementById(id);
	var xx = el.style.display;
	if ((xx != 'none') && (xx != '')) {
		el.style.display = 'none';
	} else {
		el.style.display = 'block';
	}
	return true;
}

function show_hide_lang(id, lang, titulek) {
	document.getElementById('img_' + id + '_lang').value = lang ;
	document.getElementById('img_' + id + '_titulek').value = titulek ;
	var el = document.getElementById('popup-title-edit-' + id);
	var xx = el.style.display;
	if ((xx != 'none') && (xx != '')) {
		el.style.display = 'none';
	} else {
		el.style.display = 'block';
	}
	return true;
}

function switch_class(el) {
	/*
	*/
	if (el.className != 'preview') {
		el.className = 'preview';
	} else {
		el.className = 'preview aktivni';
	}
	return true;
}

function str_replace(search, replace, subject)
{
	var result = "";
	var  oldi = 0;
	for (i = subject.indexOf (search); i > -1; i = subject.indexOf (search, i))
	{
		result += subject.substring (oldi, i);
		result += replace;
		i += search.length;
		oldi = i;
	}
	return result + subject.substring (oldi, subject.length);
}


function convert_and_redirect(string)
{
	location.href= 'mailto:'+str_replace('(zavináč)','@',string);
}

function isDefined(variable) {
	return (!(!( variable||false )))
}

function goToUrl(theUrl) {
	document.location.href = theUrl;
	return true;
}

function empty(el) {
	var x = el.value;
	if (x.substring(1,0)==' ') {
	    el.value = '';
	    el.style.color = '#000000';
	}
	return true;
}

	
function changeImage(url) { 
	if (obr = document.getElementById('nejlepsi-zamestnavatel-logo')) {
		obr.src = url;	
	} 
}

// ajax nahrani value pro tag_id
function loadurl(tag_id, dest)	{
	try	{
		xmlhttp = window.XMLHttpRequest ? new XMLHttpRequest : new ActiveXObject("Microsoft.XMLHTTP");
	} catch (e) {
		alert('browser nepodporuje ajax');
	}
	xmlhttp.onreadystatechange = function() {
		triggered(tag_id);
	};
	xmlhttp.open("GET", dest);
	xmlhttp.send(null);
}

function triggered(tag_id) {
	if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
		document.getElementById(tag_id).innerHTML = xmlhttp.responseText;
	}
}

//ajax url
function instant_url(script) {
	//var nadpis = document.getElementById('nadpis').value();
	var web_strom_id = document.getElementById('web_strom_id').value;
	var url = document.getElementById('url').value;
	var titulek = document.getElementById('titulek').value;
	var dest = 'index.php?script=struktura/detail_url_ajax/&web_strom_id='+escape(web_strom_id)+'&url='+(url)+'&titulek='+(titulek);
	//alert(dest);
	loadurl('url-box', dest);
}

function roztahnout(id, default_width) {
	var el = document.getElementById(id);
	var xx = el.style.width;
	if ((xx != default_width)) {
		el.style.width = default_width;
	} else {
		el.style.width = '';
	}
	return true;
}