function addDays(date, dayAdd) {
	millisec = (dayAdd-1) * 86400000;
	newTime = date.getTime() + millisec;
	return new Date(newTime);
}
function diffDays(date1, date2) {
	diff = Math.floor((date2.getTime() - date1.getTime())/86400000  );
	return diff;
}
function setWeekDay(yy,mm,dd){
      DataArrivo = new Date(parseInt(yy), parseInt(mm-1), parseInt(dd));
   	return(DataArrivo.getDay());
}
		
function setNumberNight() {
	var sDayVal  = Number(document.forms[0].arr_date[document.forms[0].arr_date.selectedIndex].value);
	var sYearVal = Number(document.forms[0].arr_year[document.forms[0].arr_year.selectedIndex].value);
	var sMonthVal= Number(document.forms[0].arr_mon[document.forms[0].arr_mon.selectedIndex].value);
	var dataStart = new Date(sYearVal,sMonthVal-1,sDayVal);
//alert(dataStart);

	//arrive_date.innerText=this.aryGiorni[setWeekDay(sYearVal,sMonthVal,sDayVal)];
	
	var sDayVal  = Number(document.forms[0].dep_date[document.forms[0].dep_date.selectedIndex].value);
	var sYearVal = Number(document.forms[0].dep_year[document.forms[0].dep_year.selectedIndex].value);
	var sMonthVal= Number(document.forms[0].dep_mon[document.forms[0].dep_mon.selectedIndex].value);
	var dataEnd = new Date(sYearVal,sMonthVal-1,sDayVal);
//alert(dataEnd);
	//departure_date.innerText=this.aryGiorni[setWeekDay(sYearVal,sMonthVal,sDayVal)];
	
	if (dataStart<dataEnd) {
		document.forms[0].nights.value=diffDays(dataStart, dataEnd);
	} else {
	 	document.forms[0].nights.value=2;
	 	setEndNight();
	}
	return true;
}
function setEndNight() {
	if (!isNaN(Number (document.forms[0].nights.value)) ){
		var dataEnd =  new Date();
		var sDayVal  = Number(document.forms[0].arr_date[document.forms[0].arr_date.selectedIndex].value);
		var sYearVal = Number(document.forms[0].arr_year[document.forms[0].arr_year.selectedIndex].value);
		var sMonthVal= Number(document.forms[0].arr_mon[document.forms[0].arr_mon.selectedIndex].value);
		//arrive_date.innerText=this.aryGiorni[setWeekDay(sYearVal,sMonthVal,sDayVal)];
		var dataStart = new Date(sYearVal,sMonthVal-1,sDayVal);
        var sYearini = 2007;

		dataEnd = addDays (dataStart, Number(document.forms[0].nights.value));
		document.forms[0].dep_date.options[""+dataEnd.getDate()].selected = true;
		document.forms[0].dep_mon.options[""+dataEnd.getMonth()].selected = true;
		document.forms[0].dep_year.options[""+(dataEnd.getFullYear()-sYearini)].selected = true;
		
		//departure_date.innerText=this.aryGiorni[setWeekDay(dataEnd.getYear(),dataEnd.getMonth(),dataEnd.getDate())];

	} else {
			document.forms[0].nights.value="0";
			alert ("Invalid Night number");
		}
	return true;
}


   function setMultipleValues4(y,m,d) {
   	document.forms[0].arr_year.value=y;
   	document.forms[0].arr_mon.selectedIndex=m-1;
   	for (var i=0; i<document.forms[0].arr_date.options.length; i++) {
   		if (document.forms[0].arr_date.options[i].value==d) {
   			document.forms[0].arr_date.selectedIndex=i;
   			}
   		}
      //arrive_date.innerText=this.aryGiorni[setWeekDay(y,m,d)];
   	setNumberNight();
   	}
   function setMultipleValues5(y,m,d) {
   	document.forms[0].dep_year.value=y;
   	document.forms[0].dep_mon.selectedIndex=m-1;
   	for (var i=0; i<document.forms[0].dep_date.options.length; i++) {
   		if (document.forms[0].dep_date.options[i].value==d) {
   			document.forms[0].dep_date.selectedIndex=i;
   			}
   		}
   	//departure_date.innerText = this.aryGiorni[setWeekDay(y,m,d)];	
      setNumberNight();
   	}
   function getDateString(y_obj,m_obj,d_obj) {
   	var y = y_obj.options[y_obj.selectedIndex].value;
   	var m = m_obj.options[m_obj.selectedIndex].value;
   	var d = d_obj.options[d_obj.selectedIndex].value;
   	if (y=="" || m=="") { return null; }
   	if (d=="") { d=1; }
   	return str= y+'-'+m+'-'+d;
   }