// ----------------------------------------------------------------------------------------------------------------------------------------
// date functions
// ----------------------------------------------------------------------------------------------------------------------------------------

function isLeapYear(Year) {
	if (((Year % 4)==0) && ((Year % 100)!=0) || ((Year % 400)==0)) { return true; }
	else { return false; }
}

// ----------------------------------------------------------------------------------------------------------------------------------------

function setDays(value,dayField,monthField,yearField) {
	var weekDayArray=new Array("ZO","MA","DI","WO","DO","VR","ZA");
	
	var obj=el(dayField);
	removeAllOptions(obj);
	
	var yearobj=el(yearField);
	var monthobj=el(monthField);
	var month=monthobj.value;
	
	if ((month==1) || (month==3) || (month==5) || (month==7) || (month==8) || (month==10) || (month==12)) { days=31; }
	else if ((month==4) || (month==6) || (month==9) || (month==11)) { days=30; }
	else if ((month==2) && isLeapYear(yearobj.value)) { days=29; }
	else { days=28; }

	for (i=1;i<=days;i++) { 
		var today=new Date(yearobj.value,month-1,i);
		var weekDay=today.getDay();	
		addOption(obj,"["+weekDayArray[weekDay]+"] - "+strPad(i),i);
	}
	
	obj.value=value;
}

// ----------------------------------------------------------------------------------------------------------------------------------------

function setToday(dayField,monthField,yearField) {
	var today=new Date();
	var yearobj=el(yearField);
	var monthobj=el(monthField);
	var dayobj=el(dayField);
	
	yearobj.value=today.getYear();
	monthobj.value=today.getMonth()+1;
	dayobj.value=today.getDate();
	
	yearobj.focus();
}

// ----------------------------------------------------------------------------------------------------------------------------------------