var tmp = navigator.userAgent;
var dom = document.getElementById ? true : false;
var opera = tmp.indexOf('Opera') != -1 ? true : false;
var ie = ((tmp.indexOf('MSIE') != -1) && (!opera)) ? true : false;
var dhtml = dom ? true : ie ? true : opera ? true : false;
if(!dhtml) alert('Tyto stránky nejsou optimalizovány pro tento prohlížeč.\nThis pages is not optimalized for this browser.');

var screenW = window.screen.width;
var screenH = window.screen.height;
var timer; // timer pro dhtml menu

// ziskani elementu
function getEl(el){
  return document.getElementById(el);
}

// prirazeni nejakeho stylu k prvku podle id
function itemStyle(el,cssStyle,cssVal){
	if(document.all) document.all[el].style[cssStyle]=cssVal;
	else document.getElementById(el).style[cssStyle]=cssVal;
}

// zobrazeni/skryti elementu a pripadna zmena textu
function showHide(elShowHide,elTxt,txtOld,txtNew){
	var elm = document.getElementById(elShowHide).style;
	elm.display = (!elm.display) ? 'none' : '';
	if((txtOld!='') && (txtNew!='')) changetext(elTxt,txtOld,txtNew);
}

// zmenit text v elementu podle id
function changetext(el,txtOld,txtNew){
	var elm = getEl(el);
	elm.innerHTML = (elm.innerHTML==txtOld) ? txtNew : txtOld;
}

// zaskrtnuti/odskrtnuti vsech checkboxu se zamenou textu (form,checkbox name, change el, text pro Check All a Uncheck All)
function checkUncheckAll(f,chck,el,str1,str2){
	var val;
	var elm = getEl(el);
	val = (elm.innerHTML==str1) ? 1 : 0;
	for(i=0;i<f.elements.length;i++) if(f.elements[i].name==chck) f.elements[i].checked = val;
	changetext(el,str1,str2);
}

// kontrola textu pro vyhledavani (form,hlaska pro nezadany a kratky text)
function validateSearch(f,err1,err2){
	var stat=true; var strerr="";
	if(f.q.value=="") strerr+=err1+"\n";
	if((f.q.value != "") && (f.q.value.length<3)) strerr+=err2+"\n";
	if(strerr!=""){ stat=false; alert(strerr); }
	return stat;
}

// prejit na odkaz
function jumptolink(val){
	window.location=val;
}

// otevreni fotky
function photoOpen(photoURL){
	myLeft = (screenW > 800) ? ((screenW / 2) - (390 + 10)) : 10;
	myHeight = (screenH > 600) ? 605 : 550;
	photo = window.open(''+photoURL+'','photo','width=780,height='+myHeight+',top=0,left='+myLeft+',scrollbars=yes,status=yes,resizable=yes');
	photo.focus();
}

// otevreni okna
function windowOpen(url,width,height){
	myLeft = (screenW > 800) ? ((screenW/2) - ((width/2)+10)) : 10;
	win = window.open(''+url+'','win','width='+width+',height='+height+',top=0,left='+myLeft+',scrollbars=yes,status=yes,resizable=yes,toolbar=no,menubar=yes');
	win.focus();
}

// funkce na vytvoreni odkazu pro mail
function writeMailTo(suffix,prefix) {
  location.href = "mai" + "lto:" + prefix + "@" + suffix;
}

// pridani do oblibenych polozek
function AddFavorite(linkObj,addUrl,addTitle){
	if(document.all && !window.opera){
		window.external.AddFavorite(addUrl,addTitle);
		return false;
	} else if(window.opera && window.print){
		linkObj.title = addTitle;
		return true;
	} else if((typeof window.sidebar == 'object') && (typeof window.sidebar.addPanel == 'function')){
		if(window.confirm('Přidat oblíbenou stránku jako nový panel?')){
			window.sidebar.addPanel(addTitle,addUrl,'');
			return false;
		}
	}
	window.alert('Po potvrzení stiskněte CTRL-D,\nstránka bude přidána k vašim oblíbeným odkazům.');
	return false;
}

// vytvoreni url
var nodiac = {'á':'a','č':'c','ď':'d','é':'e','ě':'e','í':'i','ň':'n','ó':'o','ř':'r','š':'s','ť':'t','ú':'u','ů':'u','ý':'y','ž':'z'};
function makeUrl(s) {
    s = s.toLowerCase();
    var s2 = '';
    for (var i=0;i<s.length;i++) {
        s2 += (typeof nodiac[s.charAt(i)]!='undefined' ? nodiac[s.charAt(i)] : s.charAt(i));
    }
    return s2.replace(/[^a-z0-9_]+/g,'-').replace(/^-|-$/g,'');
}