// VARIABLE DECLARATIONS

var digits = "0123456789";

var lowercaseLetters = "abcdefghijklmnopqrstuvwxyz";

var uppercaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

var whitespace = " \t\n\r";

var decimalPointDelimiter = ".";

var phoneNumberDelimiters = "()- ";

var validUSPhoneChars = digits + phoneNumberDelimiters;

var validWorldPhoneChars = digits + phoneNumberDelimiters + "+";

var digitsInSocialSecurityNumber = 9;

var digitsInUSPhoneNumber = 10;

var ZIPCodeDelimiters = "-";

var ZIPCodeDelimeter = "-";

var validZIPCodeChars = digits + ZIPCodeDelimiters;

var creditCardDelimiters = " ";

var mPrefix = "U heeft geen waarde voor ";
var mSuffix = " ingevuld.\nDit is een verplichte rubriek. Vult u het alstublieft nu in.";

var sAchterNaam = "Achternaam";
var sVoorletters = "Voorletters";
var sTussenvoegsel = "Tussenvoegsel";
var sAdres = "Adres";
var sGebDatum = "Geboortedatum";
var sHuisNr = "Huisnummer";
var sHuisToev = "Toevoeging huisnummer";
var sPostcode = "Postcode";
var sPlaats = "Plaatsnaam";
var sLand = "Land";
var sTelHuis = "Telefoonnummer privé";
var sTelWerk = "Telefoonnummer op het werk";
var sTelMobiel = "Nummer van mobiele telefoon";
var sEmail = "Email adres";

var iZIPCode = "Deze rubriek dient een postcode te zijn die bestaat uit 4 cijfers en 2 letters (zoals 2839 AX). Vul dit alstublieft opnieuw in."
var iUSPhone = "Deze rubriek dient een 10 cijferig telefoonnummer zijn (zoals 010 46 56 565). Vul dit alstublieft opnieuw in."
var iEmail = "Deze rubriek dient een geldig emailadres te zijn (zoals j.janssen@wxs.nl). Vul dit alstublieft opnieuw in."
var iDay = "Deze rubriek dient een dagnummer te zijn tussen de 1 en 31.  Vul dit alstublieft opnieuw in."
var iMonth = "Deze rubriek dient een maandnummer te zijn tussen de 1 en de 12.  Vul dit alstublieft opnieuw in."
var iYear = "Deze rubriek dient een 2 of 4 cijferig jaartal te zijn.  Vul dit alstublieft opnieuw in."
var iDatePrefix = "De Dag, Maand, en Jaar voor "
var iDateSuffix = " stellen geen geldige datum voor.  Vul ze alstublieft opnieuw in."

var pEntryPrompt = "Vul in: "
var pZIPCode = "postcode met 4 cijfers en 2 letters (zoals 2800 AD)."
var pUSPhone = "10 cijferig telefoonnummer (zoals 010 465 24 24)."
var pEmail = "geldig email adres (zoals j.janssen@wxs.nl)."
var pDay = "dagnummer tussen 1 en 31."
var pMonth = "maandnummer tussen 1 en 12."
var pYear = "2 of 4 cijferig jaartal."

var defaultEmptyOK = false


function makeArray(n) {

   for (var i = 1; i <= n; i++) {
      this[i] = 0
   } 
   return this
}


var daysInMonth = makeArray(12);
daysInMonth[1] = 31;
daysInMonth[2] = 29;   // must programmatically check this
daysInMonth[3] = 31;
daysInMonth[4] = 30;
daysInMonth[5] = 31;
daysInMonth[6] = 30;
daysInMonth[7] = 31;
daysInMonth[8] = 31;
daysInMonth[9] = 30;
daysInMonth[10] = 31;
daysInMonth[11] = 30;
daysInMonth[12] = 31;


function checkAdres (theField, s, emptyOK) {
  if (isOK= checkString (theField, s, emptyOK))
    theField.value= CapFirst(theField.value);
  return( isOK ); }

function checkPlaats (theField, s, emptyOK) {
  if (isOK= checkString (theField, s, emptyOK))
    theField.value= theField.value.toUpperCase();
  return( isOK ); }

function checkVoorletters (theField, s, emptyOK) {
  if (isOK= checkString (theField, s, emptyOK))
    theField.value= theField.value.toUpperCase();
  return( isOK ); }

function checkAchternaam (theField, s, emptyOK) {
  if (isOK= checkString (theField, s, emptyOK))
    theField.value= reformatAchternaam( theField.value );
  return( isOK ); }

function reformatAchternaam ( s ) {
  var i= 0;
  var naam= "";
  while (i < s.length) {
    while (i < s.length &&  charInString ( s.charAt(i), whitespace)) i++;
    var start= i;
    while (i < s.length && !charInString ( s.charAt(i), whitespace)) i++;

    woord= s.substring( start, i );
    if (isVoorvoegsel(woord))
        woord= woord.toLowerCase();
    else
        woord= CapFirst(woord)
    naam += woord + " "; };
  return ( naam ); }

function isVoorvoegsel( woord ) {
  var voorVg = new Array('van','de','der','den');
  var match= false;
  for (var n= 0; !match && n< voorVg.length; n++) {
    match= (woord.toLowerCase() == voorVg[n]); };
  return( match ) ; }

function CapFirst ( s ) {
  var str= s;
  if (isLetter(str.charAt(0)))
    str= str.charAt(0).toUpperCase() + str.substring(1).toLowerCase();
  return ( str ); }


function isEmpty(s)
{   return ((s == null) || (s.length == 0))
}


function isWhitespace (s)
{   var i;

    // Is s empty?
    if (isEmpty(s)) return true;

    // Search through string's characters one by one
    // until we find a non-whitespace character.
    // When we do, return false; if we don't, return true.

    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);

        if (whitespace.indexOf(c) == -1) return false;
    }

    // All characters are whitespace.
    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++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }

    return returnString;
}


function stripCharsNotInBag (s, bag)
{   var i;
    var returnString = "";

    // Search through string's characters one by one.
    // If character is in bag, append to returnString.

    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) != -1) returnString += c;
    }
    return returnString;
}


function stripWhitespace (s)
{   return stripCharsInBag (s, whitespace)
}


function charInString (c, s)
{   for (i = 0; i < s.length; i++)
    {   if (s.charAt(i) == c) return true;
    }
    return false
}


function stripInitialWhitespace (s)
{   var i = 0;

    while ((i < s.length) && charInString (s.charAt(i), whitespace))
       i++;
    return s.substring (i, s.length);
}


function isLetter (c)
{   return ( ((c >= "a") && (c <= "z")) || ((c >= "A") && (c <= "Z")) )
}


function isDigit (c)
{   return ((c >= "0") && (c <= "9"))
}


function isLetterOrDigit (c)
{   return (isLetter(c) || isDigit(c))
}


function isInteger (s)
{   var i;
    if (isEmpty(s)) 
       if (isInteger.arguments.length == 1) return defaultEmptyOK;
       else return (isInteger.arguments[1] == true);
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);

        if (!isDigit(c)) return false;
    }
    return true;
}


function isSignedInteger (s)
{   if (isEmpty(s)) 
       if (isSignedInteger.arguments.length == 1) return defaultEmptyOK;
       else return (isSignedInteger.arguments[1] == true);

    else {
        var startPos = 0;
        var secondArg = defaultEmptyOK;

        if (isSignedInteger.arguments.length > 1)
            secondArg = isSignedInteger.arguments[1];

        // skip leading + or -
        if ( (s.charAt(0) == "-") || (s.charAt(0) == "+") )
           startPos = 1;    
        return (isInteger(s.substring(startPos, s.length), secondArg))
    }
}


function isPositiveInteger (s)
{   var secondArg = defaultEmptyOK;
    if (isPositiveInteger.arguments.length > 1)
        secondArg = isPositiveInteger.arguments[1];
    return (isSignedInteger(s, secondArg)
         && ( (isEmpty(s) && secondArg)  || (parseInt (s, 10) > 0) ) );
}



function isNonnegativeInteger (s)
{   var secondArg = defaultEmptyOK;
    if (isNonnegativeInteger.arguments.length > 1)
        secondArg = isNonnegativeInteger.arguments[1];
    return (isSignedInteger(s, secondArg)
         && ( (isEmpty(s) && secondArg)  || (parseInt (s, 10) >= 0) ) );
}


function isNegativeInteger (s)
{   var secondArg = defaultEmptyOK;

    if (isNegativeInteger.arguments.length > 1)
        secondArg = isNegativeInteger.arguments[1];
    return (isSignedInteger(s, secondArg)
         && ( (isEmpty(s) && secondArg)  || (parseInt (s, 10) < 0) ) );
}


function isNonpositiveInteger (s)
{   var secondArg = defaultEmptyOK;

    if (isNonpositiveInteger.arguments.length > 1)
        secondArg = isNonpositiveInteger.arguments[1];

    return (isSignedInteger(s, secondArg)
         && ( (isEmpty(s) && secondArg)  || (parseInt (s, 10) <= 0) ) );
}



function isFloat (s)
{   var i;
    var seenDecimalPoint = false;
    if (isEmpty(s)) 
       if (isFloat.arguments.length == 1) return defaultEmptyOK;
       else return (isFloat.arguments[1] == true);

    if (s == decimalPointDelimiter) return false;

    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);

        if ((c == decimalPointDelimiter) && !seenDecimalPoint) seenDecimalPoint = true;
        else if (!isDigit(c)) return false;
    }
    return true;
}



function isSignedFloat (s)
{   if (isEmpty(s)) 
       if (isSignedFloat.arguments.length == 1) return defaultEmptyOK;
       else return (isSignedFloat.arguments[1] == true);
    else {
        var startPos = 0;
        var secondArg = defaultEmptyOK;

        if (isSignedFloat.arguments.length > 1)
            secondArg = isSignedFloat.arguments[1];

        if ( (s.charAt(0) == "-") || (s.charAt(0) == "+") )
           startPos = 1;    
        return (isFloat(s.substring(startPos, s.length), secondArg))
    }
}




function isAlphabetic (s)
{   var i;

    if (isEmpty(s)) 
       if (isAlphabetic.arguments.length == 1) return defaultEmptyOK;
       else return (isAlphabetic.arguments[1] == true);

    for (i = 0; i < s.length; i++)
    {   
        var c = s.charAt(i);

        if (!isLetter(c))
        return false;
    }
    return true;
}



function isAlphanumeric (s)
{   var i;
    if (isEmpty(s)) 
       if (isAlphanumeric.arguments.length == 1) return defaultEmptyOK;
       else return (isAlphanumeric.arguments[1] == true);
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number or letter.
        var c = s.charAt(i);

        if (! (isLetter(c) || isDigit(c) ) )
        return false;
    }
    return true;
}


function reformat (s)
{   var arg;
    var sPos = 0;
    var resultString = "";

    for (var i = 1; i < reformat.arguments.length; i++) {
       arg = reformat.arguments[i];
       if (i % 2 == 1) resultString += arg;
       else {
           resultString += s.substring(sPos, sPos + arg);
           sPos += arg;
       }
    }
    return resultString;
}



function isUSPhoneNumber (s)
{   if (isEmpty(s)) 
       if (isUSPhoneNumber.arguments.length == 1) return defaultEmptyOK;
       else return (isUSPhoneNumber.arguments[1] == true);
    return (isInteger(s) && s.length == digitsInUSPhoneNumber)
}


function isInternationalPhoneNumber (s)
{   if (isEmpty(s)) 
       if (isInternationalPhoneNumber.arguments.length == 1) return defaultEmptyOK;
       else return (isInternationalPhoneNumber.arguments[1] == true);
    return (isPositiveInteger(s))
}


function isZIPCode (s)
{  if (isEmpty(s)) 
       if (isZIPCode.arguments.length == 1) return defaultEmptyOK;
       else return (isZIPCode.arguments[1] == true);
   s=stripWhitespace(s);
   return (isInteger(s.substring(0, 3)) && isLetter(s.substring(4, 5)) && (s.length == 6))
}



function isEmail (s)
{   if (isEmpty(s)) 
       if (isEmail.arguments.length == 1) return defaultEmptyOK;
       else return (isEmail.arguments[1] == true);
   
    if (isWhitespace(s)) return false;
    

    var i = 1;
    var sLength = s.length;

    while ((i < sLength) && (s.charAt(i) != "@"))
    { i++
    }

    if ((i >= sLength) || (s.charAt(i) != "@")) return false;
    else i += 2;

    while ((i < sLength) && (s.charAt(i) != "."))
    { i++
    }

    if ((i >= sLength - 1) || (s.charAt(i) != ".")) return false;
    else return true;
}




function isYear (s)
{   if (isEmpty(s)) 
       if (isYear.arguments.length == 1) return defaultEmptyOK;
       else return (isYear.arguments[1] == true);
    if (!isNonnegativeInteger(s)) return false;
    return ((s.length == 2) || (s.length == 4));
}



function isIntegerInRange (s, a, b)
{   if (isEmpty(s)) 
       if (isIntegerInRange.arguments.length == 1) return defaultEmptyOK;
       else return (isIntegerInRange.arguments[1] == true);
    if (!isInteger(s, false)) return false;
    var num = parseInt (s, 10);
    return ((num >= a) && (num <= b));
}


function isMonth (s)
{   if (isEmpty(s)) 
       if (isMonth.arguments.length == 1) return defaultEmptyOK;
       else return (isMonth.arguments[1] == true);
    return isIntegerInRange (s, 1, 12);
}



function isDay (s)
{   if (isEmpty(s)) 
       if (isDay.arguments.length == 1) return defaultEmptyOK;
       else return (isDay.arguments[1] == true);   
    return isIntegerInRange (s, 1, 31);
}



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 isDate (year, month, day)
{   // catch invalid years (not 2- or 4-digit) and invalid months and days.
    if (! (isYear(year, false) && isMonth(month, false) && isDay(day, false))) return false;


    var intYear = parseInt(year, 10);
    var intMonth = parseInt(month, 10);
    var intDay = parseInt(day, 10);

    if (intDay > daysInMonth[intMonth]) return false; 
    if ((intMonth == 2) && (intDay > daysInFebruary(intYear))) return false;
    return true;
}


function prompt (s)
{   window.status = s
}


function promptEntry (s)
{   window.status = pEntryPrompt + s
}


function warnEmpty (theField, s)
{   theField.focus()
    alert(mPrefix + s + mSuffix)
    return false
}



function warnInvalid (theField, s)
{   theField.focus()
    theField.select()
    alert(s)
    return false
}



function checkString (theField, s, emptyOK)
{
if (checkString.arguments.length == 2) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    if (isWhitespace(theField.value))
       return warnEmpty (theField, s);
    else return true;
}





function reformatZIPCode (ZIPString)
{   
	ZIPString = stripWhitespace(ZIPString);
	letterDeel = ZIPString.substring(4,6);
	ZIPString = ZIPString.substring(0,4) + " " + letterDeel.toUpperCase();
	return (ZIPString);
}



function checkZIPCode (theField, emptyOK)
{   if (checkZIPCode.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else
    { var normalizedZIP = stripCharsInBag(theField.value, ZIPCodeDelimiters)
      if (!isZIPCode(normalizedZIP, false)) 
         return warnInvalid (theField, iZIPCode);
      else 
      {  // if you don't want to insert a hyphen, comment next line out
         theField.value = reformatZIPCode(normalizedZIP)
         return true;
      }
    }
}



function reformatUSPhone (USPhone)
{   return (reformat (USPhone, "", 3, " ", 3, " ", 2, " ", 2))
}


function checkUSPhone (theField, emptyOK)
{   if (checkUSPhone.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else
    {  var normalizedPhone = stripCharsInBag(theField.value, phoneNumberDelimiters)
       if (!isUSPhoneNumber(normalizedPhone, false)) 
          return warnInvalid (theField, iUSPhone);
       else 
       {  // if you don't want to reformat as (123) 456-789, comment next line out
          theField.value = reformatUSPhone(normalizedPhone)
          return true;
       }
    }
}



function checkInternationalPhone (theField, emptyOK)
{   if (checkInternationalPhone.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else
    {  if (!isInternationalPhoneNumber(theField.value, false)) 
          return warnInvalid (theField, iWorldPhone);
       else return true;
    }
}



function checkEmail (theField, emptyOK)
{   if (checkEmail.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else if (!isEmail(theField.value, false)) 
       return warnInvalid (theField, iEmail);
    else return true;
}

function checkYear (theField, emptyOK)
{   if (checkYear.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    if (!isYear(theField.value, false)) 
       return warnInvalid (theField, iYear);
    else
       return true;
}

function checkMonth (theField, emptyOK)
{   if (checkMonth.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    if (!isMonth(theField.value, false)) 
       return warnInvalid (theField, iMonth);
    else return true;
}

function checkDay (theField, emptyOK)
{   if (checkDay.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    if (!isDay(theField.value, false)) 
       return warnInvalid (theField, iDay);
    else return true;
}

function checkDate (yearField, monthField, dayField, labelString, OKtoOmitDay)
{   // Next line is needed on NN3 to avoid "undefined is not a number" error
    // in equality comparison below.
    if (checkDate.arguments.length == 4) OKtoOmitDay = false;
    if (!isYear(yearField.value)) return warnInvalid (yearField, iYear);
    if (!isMonth(monthField.value)) return warnInvalid (monthField, iMonth);
    if ( (OKtoOmitDay == true) && isEmpty(dayField.value) ) return true;
    else if (!isDay(dayField.value)) 
       return warnInvalid (dayField, iDay);

    if (isDate (yearField.value, monthField.value, dayField.value))
       {
       if (yearField.value< 100)
	    yearField.value= parseInt(yearField.value) + 1900;
       return true;
       };
    alert (iDatePrefix + labelString + iDateSuffix)
    return false
}

function getRadioButtonValue (radio)
{   for (var i = 0; i < radio.length; i++)
    {   if (radio[i].checked) { break }
    }
    return radio[i].value
}