function isInteger(s){
	var i;
    for (i = 0; i < s.length; i++){   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag){
	var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++){   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function daysInFebruary (year){
	// February has 29 days in any year evenly divisible by four,
    // EXCEPT for centurial years which are not also divisible by 400.
    return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
	for (var i = 1; i <= n; i++) {
		this[i] = 31
		if (i==4 || i==6 || i==9 || i==11) {this[i] = 30}
		if (i==2) {this[i] = 29}
   } 
   return this
}

function isDate(dtStr){

	var dtCh= "/";
	var minYear=1900;
	var maxYear=2100;

	var daysInMonth = DaysArray(12)
	var pos1=dtStr.indexOf(dtCh)
	var pos2=dtStr.indexOf(dtCh,pos1+1)
	var strDay=dtStr.substring(0,pos1)
	var strMonth=dtStr.substring(pos1+1,pos2)
	var strYear=dtStr.substring(pos2+1)
	strYr=strYear
	if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1)
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
	}
	month=parseInt(strMonth)
	day=parseInt(strDay)
	year=parseInt(strYr)
	if (pos1==-1 || pos2==-1){
		//alert("The date format should be : gg/mm/aaaa")
		return -1;
	}
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
		// alert("Please enter a valid day")
		return -2;
	}
	if (strMonth.length<1 || month<1 || month>12){
		// alert("Please enter a valid month")
		return -3;
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		// alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return -4;
	}
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
		alert("Please enter a valid date")
		return -5;
	}
return 0;
}

function trim(stringToTrim) {
	return stringToTrim.replace(/^\s+|\s+$/g,"");
}

function checkCF(codfisc)
{
	var cf, i, s, set1, set2, setpari, setdisp;
	var fcf=/^[A-Z0-9]{16}$/;
	cf=trim(codfisc.toUpperCase());
  if( cf == "" ) {
		return false;
	}
	if( !fcf.test(cf) ) {
		return false;
	}

	set1 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	set2 = "ABCDEFGHIJABCDEFGHIJKLMNOPQRSTUVWXYZ";
	setpari = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	setdisp = "BAKPLCQDREVOSFTGUHMINJWZYX";
	s = 0;
	for( i = 1; i <= 13; i += 2 ) {
		s += setpari.indexOf( set2.charAt( set1.indexOf( cf.charAt(i) )));
	}
	for( i = 0; i <= 14; i += 2 ) {
		s += setdisp.indexOf( set2.charAt( set1.indexOf( cf.charAt(i) )));
	}
	if( s%26 != cf.charCodeAt(15)-'A'.charCodeAt(0) ) {
		return false;
	}
		
	return true;
}

function checkform(form)
{
  var isCorrect=true;

  if(isCorrect && form.surname.value=="") {
    alert("Inserire il cognome");
    isCorrect=false;
  }
  if(isCorrect && form.name.value=="") {
    alert("Inserire il nome");
    isCorrect=false;
  }
  if(isCorrect && checkCF(form.codfisc.value)==false) {
    alert("Il codice fiscale non risulta corretto");
    isCorrect=false;
  }
	var valDate=isDate(form.birthdate.value)
  if(isCorrect && valDate!=0) {
		if(valDate==-1) {
			alert("Inserire la data di nascita nel formato GG/MM/AAAA");
		}
		else if(valDate==-2) {
			alert("Inserire la data di nascita con il giorno corretto");		
		}
		else if(valDate==-3) {
			alert("Inserire la data di nascita con il mese corretto");		
		}
		else if(valDate==-4) {
			alert("Inserire la data di nascita con l'anno corretto (a 4 cifre)");		
		}
		else if(valDate==-5) {
			alert("Inserire una data di nascita valida");
		}
		else {
			alert("Inserire la data di nascita");		
		}
    isCorrect=false;
  }
  if(isCorrect && form.birthcity.value=="") {
    alert("Inserire la citta' di nascita");
    isCorrect=false;
  }
  if(isCorrect && form.birthcounty.value=="") {
    alert("Inserire la provincia di nascita");
    isCorrect=false;
  }
  if(isCorrect && form.city.value=="") {
    alert("Inserire la citta' di residenza");
    isCorrect=false;
  }
  if(isCorrect && form.county.value=="") {
    alert("Inserire la provincia di residenza");
    isCorrect=false;
  }
  if(isCorrect && form.address.value=="") {
    alert("Inserire l'indirizzo di residenza");
    isCorrect=false;
  }
  if(isCorrect && form.number.value=="") {
    alert("Inserire il numero di residenza");
    isCorrect=false;
  }
  if(isCorrect && form.cap.value=="") {
    alert("Inserire il cap di residenza");
    isCorrect=false;
  }
  if(isCorrect && (form.homephone.value=="" && form.mobilephone.value=="")) {
    alert("Inserire almeno un numero di telefono");
    isCorrect=false;
  }
  if(isCorrect && form.email.value=="") {
    alert("Inserire l'email");
    isCorrect=false;
  }
  if(isCorrect && !form.readed.checked) {
    alert("E' necessario accettare le norme statutarie");
    isCorrect=false;
  }
  if(isCorrect && !form.privacy.checked) {
    alert("E' necessario consentire il trattamento dei dati");
    isCorrect=false;
  }
  
  return isCorrect;
}