function objGet(x) {
	if (typeof x != 'string') return x;
	else if (Boolean(document.getElementById)) return document.getElementById(x);
	else if (Boolean(document.all)) return eval('document.all.'+x);  // pro MSIE 4
	else return null;
}

function objSetStyle (obj,prop,val) {
	var o = objGet(obj);
	if (o && o.style) {
		eval ('o.style.'+prop+'="'+val+'"');
		return true;
		}
	else return false;
}

function objRetStyle (obj, prop) {
	var o = objGet(obj);
	if (o && o.style) return eval('o.style.'+ prop);
	else return false;
}

function objShow (obj,on) {
	return objSetStyle(obj,'visibility',(on) ? 'visible' : 'hidden');
}

function objDisplay (obj,on,type) {
	if (on && !type) type = 'block';
	return objSetStyle(obj,'display',(on) ? type : 'none');
}

function objPrepinac (obj) {
	if (objRetStyle(obj, 'display') == 'block' ) type = 'none';
	else type = 'block';
	return objSetStyle(obj,'display', type);
}

//var first = true;
//var class_name;

sfHover = function() {
	var o = objGet('menu');
	if (o){
		var sfEls = o.getElementsByTagName('LI');
		for (var i=0; i<sfEls.length; i++) {
			sfEls[i].onmouseover=function() {
				this.className+=" sfhover";
			}
			sfEls[i].onmouseout=function() {
				this.className=this.className.replace(/ ?over/gi, "");
			}
		}
	}
}

if (window.attachEvent) window.attachEvent("onload", sfHover);

function checkFormEmpty (obj,hlaska) {
	var o = objGet(obj);
	if (o && o.value == '') {
		alert (hlaska);		
		o.focus();
		return false;
		}
	else return true;
}

function checkFormEmptyNF (obj,hlaska) {
	var o = objGet(obj);
	if (o && o.value == '') {
		alert (hlaska);		
		return false;
		}
	else return true;
}

function checkFormRadio (obj,hlaska) {
	var o = document.getElementsByName(obj);
	if (o.length > 0){
		for (var i=0; i < o.length;i++){
			if (o[i].checked) return true;
		}
		alert (hlaska);		
		return false;
	}
	return true;
}

function checkFormEmptyPod (obj,hlaska,podminka) {
	var o = objGet(obj);
	if (o && podminka) {
		alert (hlaska);		
		o.focus();
		return false;
		}
	else return true;
}

function checkFormNazev (obj,hlaska,nazev) {
	var o = objGet(obj);
	if (o && o.value==nazev) {
		alert (hlaska);		
		o.focus();
		return false;
		}
	else return true;
}

function checkFormSizeMax (obj,hlaska,cislo) {
	var o = objGet(obj);
	if (o && o.value.length > cislo) {
		alert (hlaska);		
		o.focus();
		return false;
		}
	else return true;
}

function checkFormSizeMin (obj,hlaska,cislo) {
	var o = objGet(obj);
	if (o && o.value.length < cislo) {
		alert (hlaska);		
		o.focus();
		return false;
	}
	else return true;
}


function regVyraz(obj, hlaska, re){
	var o = objGet(obj);  
	if (o && o.value.search(re) != 0){
		alert (hlaska);		
		o.focus();
		return false;
	}
	else return true;
}

function checkEmail(adresa, hlaska) {
	re = /^[^.]+(\.[^.]+)*@([^.]+[.])+[a-z]{2,4}$/;
	return regVyraz(adresa, hlaska, re);
}

function checkDatum (obj, hlaska){
	re = /^((0[1-9])|([12][0-9])|(3[01])){1}\.((0[1-9])|(1[0-2])){1}\.[1-9][0-9]{3}$/;
	return regVyraz(obj, hlaska, re);
}

function openW(odkaz, winName, status){
	var retValue = true; 
	my_t_win = window.open(odkaz,winName, status);
	if (my_t_win==null || typeof(my_t_win)=="undefined") 
      retValue=false; 
	my_t_win.focus();  
return retValue; 
}

function vypoctiStred(w, h){
	var stred = new Array();
	stred['left'] = (screen.availWidth - w) / 2;
    stred['top'] = (screen.availHeight - h) / 2;
return stred;
}

function vratVelikostOkna(mezeraL, mezeraT, maxW, maxH){
	var stred = vypoctiStred(maxW, maxH);
	var okno = new Array();
	okno['width'] = screen.availWidth-(mezeraL * 2);
	okno['left'] = mezeraL;
	okno['height'] = screen.availHeight-(mezeraT * 2);
	okno['top'] = mezeraT;
	//pokud je mozna sirka vetsi jak maximum, ktere chci pak dosad stred
	if (maxW > 0 && okno['width'] > maxW ){
		okno['width'] = maxW;
		okno['left'] = stred['left'];
	}
	if (maxH > 0 && okno['height'] > maxH ){
		okno['height'] = maxH;
		okno['top'] = stred['top'];
	}

return okno;
}

function openPoslSoub(link, winName){
	var h = 410;	
	var w = 610;
	stred = vypoctiStred(w, h);
	return openW(link.href, winName, "menubar=no,location=no,resizable=yes,scrollbars=yes,status=no,toolbar=no, width="+w+",height="+h+",top="+stred['top']+",left="+stred['left']); 
}

function openCertifikat(link, winName){
	//nepouzivam, funguje;
	okno = vratVelikostOkna(50, 50, 620);
	return openW(link.href, winName, "menubar=no,location=no,resizable=yes,scrollbars=yes,status=no,toolbar=no, width="+okno['width']+",height="+okno['height']+",top="+okno['top']+",left="+okno['left']); 
}

function openMaps(link, winName){
	okno = vratVelikostOkna(50, 100);
	return openW(link.href, winName, "menubar=no,location=no,resizable=yes,scrollbars=yes,status=no,toolbar=no, width="+okno['width']+",height="+okno['height']+",top="+okno['top']+",left="+okno['left']); 
}