//the javascript below is used to check validity of Date
//provided by DateForm ( day, month and year drop downs )


function checkValidityOfDate(form) {
    var day = document.getElementsByName(form+".day")[0].value;
    var month = document.getElementsByName(form+".month")[0].value;
    var year = document.getElementsByName(form+".year")[0].value;
    return checkDate(day, month, year);
}

function checkValidityOfDate2(form) {
    var day = document.getElementsByName(form+".day")[0].value;
    var month = document.getElementsByName(form+".month")[0].value;
    var year = document.getElementsByName(form+".year")[0].value;
  return checkDate2(day, month, year);
}

function isDate(tag, monat, jahr){
 if(tag > 0 && monat > 0){
   if( ((monat == 4 || monat == 6 || monat == 9 || monat == 11) && tag == 31)
    || (monat == 2 && tag > 29)
    || (monat == 2 && tag == 29 && jahr/4 != parseInt(jahr/4))
    || tag > 31 || monat > 12){
     return false;
   }
   return true;
 }
 else return false;
}

function getLastDayOfMonth(monat, jahr){
  var day;
  if(monat == 4 || monat == 6 || monat == 9 || monat == 11){
  day = 30;
  }else if (monat == 1 || monat == 3 || monat == 5 || monat == 7
      || monat == 9 || monat == 10 || monat == 12){
  day = 31;
 }else if (monat == 2 && jahr/4 == parseInt(jahr/4) ){
  day = 29;
 }else day = 28;
// alert(day);
 return day;
}

function checkDate(tag, monat, jahr){
  if (tag != "" && monat != "") {
    if (!isDate(tag, monat, jahr)){
       alert("La date n'est pas valide");
         return false;
         }else return true;
  }
}
function checkDate2(tag, monat, jahr){
  if (tag != "" && monat != "") {
    if (!isDate(tag, monat, jahr)){
       alert("la data non è valida");
         return false;
         }else return true;
  }
}