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 SSNDelimiters = "- ";
var validSSNChars = digits + SSNDelimiters;
var digitsInSocialSecurityNumber = 9;
var digitsInUSPhoneNumber = 10;
var ZIPCodeDelimiters = "-";
var ZIPCodeDelimeter = "-"
var validZIPCodeChars = digits + ZIPCodeDelimiters
var digitsInZIPCode1 = 5
var digitsInZIPCode2 = 9
var creditCardDelimiters = " "
var mPrefix = "You did not enter a value into the "
var mSuffix = " field. This is a required field. Please enter it now."
var sUSLastName = "Last Name"
var sUSFirstName = "First Name"
var sWorldLastName = "Family Name"
var sWorldFirstName = "Given Name"
var sTitle = "Title"
var sCompanyName = "Company Name"
var sUSAddress = "Street Address"
var sWorldAddress = "Address"
var sCity = "City"
var sProvince = "Province"
var sStateCode = "State Code"
var sWorldState = "State, Province, or Prefecture"
var sCountry = "Country"
var sZIPCode = "ZIP Code"
var sWorldPostalCode = "Postal Code"
var sPhone = "Phone Number"
var sFax = "Fax Number"
var sDateOfBirth = "Date of Birth"
var sExpirationDate = "Expiration Date"
var sEmail = "Email"
var sSSN = "Social Security Number"
var sCreditCardNumber = "Credit Card Number"
var sOtherInfo = "Other Information"
var iMidInit = "This field must be a valid letter. Please reenter it now."
var iStateCode = "This field must be a valid two character U.S. state abbreviation (like CA for California). Please reenter it now."
var iZIPCode = "This field must be a 5 or 9 digit U.S. ZIP Code (like 94043). Please reenter it now."
var iWorldZIPCode = "This field must be an alphanumeric Postal Code. Please reenter it now."
var iUSPhone = "This field must be a 10 digit U.S. phone number (like 415 555 1212). Please reenter it now."
var iWorldPhone = "This field must be a valid international phone number. Please reenter it now."
var iSSN = "This field must be a 9 digit U.S. social security number (like 123 45 6789). Please reenter it now."
var iEmail = "This field must be a valid email address (like foo@bar.com). Please reenter it now."
var iCreditCardPrefix = "This is not a valid "
var iCreditCardSuffix = " credit card number. (Click the link on this form to see a list of sample numbers.) Please reenter it now."
var iDay = "This field must be a day number between 1 and 31.  Please reenter it now."
var iMonth = "This field must be a month number between 1 and 12.  Please reenter it now."
var iYear = "This field must be a 2 or 4 digit year number.  Please reenter it now."
var iDatePrefix = "The Day, Month, and Year for "
var iDateSuffix = " do not form a valid date.  Please reenter them now."
var pEntryPrompt = "Please enter "
var pStateCode = "a 2 character code (like CA)."
var pZIPCode = "a 5 or 9 digit U.S. ZIP Code (like 94043)."
var pUSPhone = "a 10 digit U.S. phone number (like 415 555 1212)."
var pWorldPhone = "an international phone number."
var pSSN = "a 9 digit U.S. social security number (like 123 45 6789)."
var pEmail = "a valid email address (like foo@bar.com)."
var pCreditCard = "a valid credit card number."
var pDay = "a day number between 1 and 31."
var pMonth = "a month number between 1 and 12."
var pYear = "a 2 or 4 digit year number."
var pLogin = "a login name (like VEGAS7777)."
var pPassword = "a password (letters and numbers only)."
var pRePassword = "your password again."
var pSecurityQuestion = "select a security question you will know the answer to."
var pSecretAnswer = "your secret answer to the security question."
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;   
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 isEmpty(s)
{   return ((s == null) || (s.length == 0))
}

function isWhitespace (s)

{   var i;


    if (isEmpty(s)) return true;


    for (i = 0; i < s.length; i++)
    {   
        var c = s.charAt(i);

        if (whitespace.indexOf(c) == -1) return false;
    }

    return true;
}


function stripCharsInBag (s, bag)

{   var i;
    var returnString = "";

    for (i = 0; i < s.length; i++)
    {   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }

    return returnString;
}


function stripCharsNotInBag (s, bag)

{   var i;
    var returnString = "";


    for (i = 0; i < s.length; i++)
    {   
        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++)
    {   
        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];

        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) > 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) >= 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) < 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) <= 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++)
    {   
        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++)
    {   
        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 isSSN (s)
{   if (isEmpty(s)) 
       if (isSSN.arguments.length == 1) return defaultEmptyOK;
       else return (isSSN.arguments[1] == true);
    return (isInteger(s) && s.length == digitsInSocialSecurityNumber)
}

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);
   	return (isInteger(s) && 
            ((s.length == digitsInZIPCode1) ||
             (s.length == digitsInZIPCode2)))
}

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)
{   
    return (  ((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0) ) ) ? 29 : 28 );
}



function isDate (year, month, day)
{   
    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) {   
	if (ZIPString.length == 5) 
		return ZIPString;
    	else 
		return (reformat (ZIPString, "", 5, "-", 4));
}



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, " ", 4))
}



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 { 
          		theField.value = reformatUSPhone(normalizedPhone)
          		return true;
       	}
   	 }
}


function checkInternationalPhone (theField, emptyOK){   
//return true;
return (reformat (theField.value, "", 3, " ", 3, " ", 4))
}


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 reformatSSN (SSN)
{   return (reformat (SSN, "", 3, "-", 2, "-", 4))
}


function checkSSN (theField, emptyOK)
{   if (checkSSN.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else
    {  var normalizedSSN = stripCharsInBag(theField.value, SSNDelimiters)
       if (!isSSN(normalizedSSN, false)) 
          return warnInvalid (theField, iSSN);
       else 
       {  // if you don't want to reformats as 123-456-7890, comment next line out
          theField.value = reformatSSN(normalizedSSN)
          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))
       return true;
    alert (iDatePrefix + labelString + iDateSuffix)
    return false
}

function checkCreditCard (radio, theField)
{   var cardType = getRadioButtonValue (radio)
    var normalizedCCN = stripCharsInBag(theField.value, creditCardDelimiters)
    if (!isCardMatch(cardType, normalizedCCN)) 
       return warnInvalid (theField, iCreditCardPrefix + cardType + iCreditCardSuffix);
    else 
    {  theField.value = normalizedCCN
       return true
    }
}

function isCreditCard(st) {
  if (st.length > 19)
    return (false);

  sum = 0; mul = 1; l = st.length;
  for (i = 0; i < l; i++) {
    digit = st.substring(l-i-1,l-i);
    tproduct = parseInt(digit ,10)*mul;
    if (tproduct >= 10)
      sum += (tproduct % 10) + 1;
    else
      sum += tproduct;
    if (mul == 1)
      mul++;
    else
      mul--;
  }
// Uncomment the following line to help create credit card numbers
// 1. Create a dummy number with a 0 as the last digit
// 2. Examine the sum written out
// 3. Replace the last digit with the difference between the sum and
//    the next multiple of 10.

//  document.writeln("<BR>Sum      = ",sum,"<BR>");
//  alert("Sum      = " + sum);

  if ((sum % 10) == 0)
    return (true);
  else
    return (false);

} 


function isVisa(cc)
{
  if (((cc.length == 16) || (cc.length == 13)) &&
      (cc.substring(0,1) == 4))
    return isCreditCard(cc);
  return false;
} 

function isMasterCard(cc)
{
  firstdig = cc.substring(0,1);
  seconddig = cc.substring(1,2);
  if ((cc.length == 16) && (firstdig == 5) &&
      ((seconddig >= 1) && (seconddig <= 5)))
    return isCreditCard(cc);
  return false;

} 


function isCardMatch (cardType, cardNumber)
{

	cardType = cardType.toUpperCase();
	var doesMatch = true;

	if ((cardType == "VISA") && (!isVisa(cardNumber)))
		doesMatch = false;
	if ((cardType == "MASTERCARD") && (!isMasterCard(cardNumber)))
		doesMatch = false;
	return doesMatch;

}  


function IsCC (st) {
    return isCreditCard(st);
}

function IsVisa (cc)  {
  return isVisa(cc);
}

function IsVISA (cc)  {
  return isVisa(cc);
}

function IsMasterCard (cc)  {
  return isMasterCard(cc);
}

function IsMastercard (cc)  {
  return isMasterCard(cc);
}

function IsMC (cc)  {
  return isMasterCard(cc);
}


function IsCardMatch (cardType, cardNumber)  {
  return isCardMatch (cardType, cardNumber);
}