var cl= 0;

function invert()
{
    f= document.getElementById("form_mm");
    e= f.elements;
    st = true;
    var status = false;
    for(i= 0; i<e.length; i++)
    if(e[i].type=="checkbox")
    {
        if (st) {
            st = false;
            status = e[i].checked;
        }
        e[i].checked= !e[i].checked;
    }
}


var hover_color = null;
var hover_unr_color = null;
// změna pozadí řádku při najetí myši

function hlt(obj,w){
	if (hover_color == null) hover_color = getStyle('hlt', "color");
	if (hover_unr_color == null) hover_unr_color = getStyle('hlt_unr', "color");
	var tds = obj.getElementsByTagName('td');
	
	for(i=0;i < tds.length;i++) {
		if (w == 1) {
			tds[i].style.backgroundColor = (obj.className=="new" ? hover_color : hover_unr_color);
		} else tds[i].style.backgroundColor = "";
	}
}


function getStyle(el, style) {
	if(!document.getElementById) return;
	el = document.getElementById(el);
	var value = el.style[style];
	if(!value) {
		if(document.defaultView)
			value = document.defaultView.getComputedStyle(el, "").getPropertyValue(style);
		else if(el.currentStyle)
			value = el.currentStyle[style];
		return value;
	}
	
}

function CheckDelMsg(){
    // really delete?
    if(!confirm("Opravdu smazat?")) return false;
    return true;
    // all is OK, submit it
}


function is_mail(mail){
    re = "^[^.]+(\.[^.]+)*@([^.]+[.])+[a-z]{2,4}$";
    return mail.search(re) == 0;
}