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

function y2k(number) { return (number < 1000) ? number + 1900 : number; }

function daysElapsed(date1,date2) {
	date1=new Date(date1)
	date2=new Date(date2)
    var difference =
        Date.UTC(y2k(date1.getYear()),date1.getMonth(),date1.getDate(),0,0,0)
      - Date.UTC(y2k(date2.getYear()),date2.getMonth(),date2.getDate(),0,0,0);
    return difference/1000/60/60/24;
}


function CheckMonth(Month){
//var NoOfDays;
CurrDate= new Date();
Curryear=CurrDate.getFullYear();
switch(Month){
case "1" : 
case "3" :
case "5" :
case "7" :
case "8" :
case "10" :
case "12" :
//,5,7,8,10,12 ::
NoOfDays = 31;
//alert(NoOfDays);
break;
case "4" :
case "6" :
case "9" :
case "11" :
NoOfDays = 30;
//alert(NoOfDays);
break;
case "2" :
if (isLeapYear(Curryear))
NoOfDays = 29;
else NoOfDays = 28;
//alert(NoOfDays);
}
//alert(NoOfDays);
return NoOfDays;
}

//***********MAIN FUNCTION***********************************
//***********************************************************

function CheckDate(){
CurrDate= new Date();
Curryear=CurrDate.getFullYear();
Today = CurrDate.getDate();
//alert ("date: "+Today);
nextyear=Curryear+1;
currmonth=CurrDate.getMonth() +1;
//alert("nextyear "+nextyear)
Month1=this.document.form2.Month1.value;
//Month1=parseInt(Month1)
Month2=this.document.form2.Month2.value;
//Month2=parseInt(Month2)
Day1=this.document.form2.Day1.value;
time1=this.document.form2.time1.value;
Day2=this.document.form2.Day2.value;
time2=this.document.form2.time2.value;
year1=this.document.form2.year1.value;
year2=this.document.form2.year2.value;
//Month2=8


// Variable aus der Menueauswahl
//state=this.document.form2.state.value;
//airport=this.document.form2.airport.value;
//type=this.document.form2.type.value;

//Abfrage state
//if (state == 0)
//{alert ("Bitte Anmietland auswählen")
//return false}

//Abfrage station
//if (airport == 0)
//{alert ("Please choose a rental station")
//return false}


//Abfrage Type
//if (type == 0)
//{alert ("Bitte Produkt auswählen")
//return false}


//Abfrage day1
if (Day1 <= 0)
{alert ("Please choose arrival day")
return false}

//Abfrage Monat1
if (Month1 <= 0)
{alert ("Please choose a arrival month")
return false}

//Abfrage day2
if (Day2 <= 0)
{alert ("Please choose a depature day")
return false}

//Abfrage day2
if (Month2 <= 0)
{alert ("Please choose a depature month")
return false}


//alert (Month2)
// Check if number of days in a month 
Days1 = CheckMonth(Month1);
//alert(Days1)
//check if number of days in a month been selected correctly
if (Day1 > Days1)
{
alert("Month has only "+Days1+" days")
return false
}

//status = checkday(Day1, Days1, "Start month")

Days2 = CheckMonth(Month2)
if (Day2 > Days2)
{
//alert(Days2)
alert("Month has only"+Days2+"days")
return false
}
//Month1=parseInt(Month1)
//Month2=parseInt(Month2)
//mdiff=(Month1)+(Month2)
//alert (mdiff)

Day1=Number(Day1)
Day2=Number(Day2)
Month1=Number(Month1)
Month2=Number(Month2)
time1=Number(time1)
time2=Number(time2)
diff=(Month1)+(Month2)
//alert (diff)
extraday=true
if (((Month1 == currmonth) && (year1 == Curryear) && ((Day1 - Today) < 1)) || ((Month1 < currmonth) && (year1 == Curryear)))
{
alert ("Sorry,  min. 1 days in advance")
return false }

else if ((Month2 == Month1) && (Day1 > Day2) && (year1 == year2)) 
{ alert ("The depature month can not be earlier as the arriving month")

return false
//alert(year1+",  "+year2);
}
else if ((Month2 < Month1) && (year1 == year2)) 
{ 
//alert(Month1)
//alert(Month2)
alert ("The depature date can not be ealier as the arriving date")
return false
//alert(year1+",  "+year2);
}
else if ((Month2 == Month1) && (Day1 == Day2) && (year1 == year2) && (time2 <= time1)){
	alert ("The start date can not be the same as the end date")
	extraday=false
	return false
	}

datex=  Day1+"/"+ Month1 +"/"+year1
datey= Day2+"/"+ Month2 +"/"+year2
date1= new Date(year1,Month1-1,Day1)
date2= new Date(year2,Month2-1,Day2)


// Befehl für die Zwischenanzeige
//alert(date1+", "+date2)


document.form2.date1.value=datex
document.form2.date2.value=datey
//alert (daysElapsed(new Date(2003,2,6),new Date(2003,1,31)));
//alert (daysElapsed(date2,date1));
daysbooked = (daysElapsed(date2,date1))
//if (daysbooked == 0)
//daysbooked = daysbooked+1
//time1=Number(time1)
//time2=Number(time2)
//alert(time1)
//alert(time2)
//alert(time1+time2)

if ((time2 > time1) && (extraday != false))
daysbooked = daysbooked+1
//alert (daysbooked)
if (daysbooked <= 0)
{alert ("Minimum is 1 day.  Please choose again")
return false}
//alert(Month1);
//alert(Month2);
document.form2.daysbooked.value = daysbooked
}

//-->