// VARIABLE DECLARATIONS

var digits = "0123456789";

var lowercaseLetters = "abcdefghijklmnopqrstuvwxyz"

var uppercaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"


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


// decimal point character differs by language and culture
var decimalPointDelimiter = "."


// non-digit characters which are allowed in phone numbers
var phoneNumberDelimiters = "()- ";


// characters which are allowed in US phone numbers
var validUSPhoneChars = digits + phoneNumberDelimiters;


// characters which are allowed in international phone numbers
// (a leading + is OK)
var validWorldPhoneChars = digits + phoneNumberDelimiters + "+";


// non-digit characters which are allowed in
// Social Security Numbers
var SSNDelimiters = "- ";


// characters which are allowed in Social Security Numbers
var validSSNChars = digits + SSNDelimiters;


// U.S. Social Security Numbers have 9 digits.
// They are formatted as 123-45-6789.
var digitsInSocialSecurityNumber = 9;


// U.S. phone numbers have 10 digits.
// They are formatted as 123 456 7890 or (123) 456-7890.
var digitsInUSPhoneNumber = 10;


// non-digit characters which are allowed in ZIP Codes
var ZIPCodeDelimiters = "-";


// our preferred delimiter for reformatting ZIP Codes
var ZIPCodeDelimeter = "-"


// characters which are allowed in Social Security Numbers
var validZIPCodeChars = digits + ZIPCodeDelimiters


// U.S. ZIP codes have 5 or 9 digits.
// They are formatted as 12345 or 12345-6789.
var digitsInZIPCode1 = 5
var digitsInZIPCode2 = 9


// non-digit characters which are allowed in credit card numbers
var creditCardDelimiters = "- \s"


// CONSTANT STRING DECLARATIONS
// (grouped for ease of translation and localization)

// m is an abbreviation for "missing"

var mPrefix = "You did not enter a value into the "
var mSuffix = " field. This is a required field. Please enter it now."

// s is an abbreviation for "string"
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 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"


// i is an abbreviation for "invalid"
var iStateCode = "This field must be a valid two character U.S. state abbreviation (like TX for Texas). Please reenter it."
var iZIPCode = "This field must be a 5 or 9 digit U.S. ZIP Code (like 14610). Please reenter it."
var iUSPhone = "This field must be a 10 digit U.S. phone number (like 716-555-1212). Please reenter it."
var iWorldPhone = "This field must be a valid international phone number. Please reenter it."
var iSSN = "This field must be a 9 digit U.S. social security number (like 123-45-6789). Please reenter it."
var iEmail = "This field must be a valid email address (like name@domain.com)... Please reenter it."
var iCreditCardPrefix = "This is not a valid "
var iCreditCardSuffix = " credit card number... Please reenter it."
var iDay = "This field must be a day number between 1 and 31.  Please reenter it."
var iMonth = "This field must be a month number between 1 and 12.  Please reenter it."
var iYear = "This field must be a 2 or 4 digit year number.  Please reenter it."
var iDatePrefix = "The Day, Month, and Year for "
var iDateSuffix = " do not form a valid date.  Please reenter them."


// p is an abbreviation for "prompt"
var pEntryPrompt = "Please enter a "
var pStateCode = "2 character code (like CA)."
var pZIPCode = "5 or 9 digit U.S. ZIP Code (like 14610)."
var pUSPhone = "10 digit U.S. phone number (like 716-555-1212)."
var pWorldPhone = "international phone number."
var pSSN = "9 digit U.S. social security number (like 123-45-6789)."
var pEmail = "valid email address (like name@domain.com)."
var pCreditCard = "valid credit card number."
var pDay = "day number between 1 and 31."
var pMonth = "month number between 1 and 12."
var pYear = "2 or 4 digit year number."

var defaultEmptyOK = false
var sendFileOK = false
var encrypt_it = true


function makeArray(n) {
//*** BUG: If I put this line in, I get two error messages:
//(1) Window.length can't be set by assignment
//(2) daysInMonth has no property indexed by 4
//If I leave it out, the code works fine.
//   this.length = 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;


// Valid U.S. Postal Codes for states, territories, armed forces, etc.
// See http://www.usps.gov/ncsc/lookups/abbr_state.txt.
var USStateCodeDelimiter = "|";
var USStateCodes = "AL|AK|AS|AZ|AR|CA|CO|CT|DE|DC|FM|FL|GA|GU|HI|ID|IL|IN|IA|KS|KY|LA|ME|MH|MD|MA|MI|MN|MS|MO|MT|NE|NV|NH|NJ|NM|NY|NC|ND|MP|OH|OK|OR|PW|PA|PR|RI|SC|SD|TN|TX|UT|VT|VI|VA|WA|WV|WI|WY|AE|AA|AE|AE|AP"


// Check whether string s is empty.
function isEmpty(s)
{   return ((s == null) || (s.length == 0))
}


// Returns true if string s is empty or
// whitespace characters only.
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;
}


// Removes all characters which appear in string bag from string s.
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;
}


// Removes all characters which do NOT appear in string bag
// from string s.
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;
}


// Removes all whitespace characters from s.
// Global variable whitespace (see above)
// defines which characters are considered whitespace.
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")) )
}


// Returns true if character c is a digit
// (0 .. 9).
function isDigit (c)
{   return ((c >= "0") && (c <= "9"))
}


// Returns true if character c is a letter or digit.
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);

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

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

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

	// All characters are numbers.
	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) > 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++)
	{
		// Check that current character is number.
		var c = s.charAt(i);

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

	// All characters are numbers.
	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];

		// skip leading + or -
		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);

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

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

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

	// All characters are letters.
	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;
	}

	// All characters are numbers or letters.
	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 isStateCode(s)
{   if (isEmpty(s))
	   if (isStateCode.arguments.length == 1) return defaultEmptyOK;
	   else return (isStateCode.arguments[1] == true);
	return ( (USStateCodes.indexOf(s) != -1) &&
			 (s.indexOf(USStateCodeDelimiter) == -1) )
}


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;

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

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

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

	// there must be at least one character after the .
	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);
	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;

	// Explicitly change type to integer to make code work in both
	// JavaScript 1.1 and JavaScript 1.2.
	var intYear = parseInt(year);
	var intMonth = parseInt(month);
	var intDay = parseInt(day);

	// catch invalid days, except for February
	if (intDay > daysInMonth[intMonth]) return false;

	if ((intMonth == 2) && (intDay > daysInFebruary(intYear))) return false;

	return true;
}


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


// Display data entry prompt string s in status bar.
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
}




/* FUNCTIONS TO INTERACTIVELY CHECK VARIOUS FIELDS. */


function checkString (theField, s, emptyOK)
{   // Next line is needed on NN3 to avoid "undefined is not a number" error
	// in equality comparison below.
	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 checkStateCode (theField, emptyOK)
{   if (checkStateCode.arguments.length == 1) emptyOK = defaultEmptyOK;
	if ((emptyOK == true) && (isEmpty(theField.value))) return true;
	else
	{  theField.value = theField.value.toUpperCase();
	   if (!isStateCode(theField.value, false))
		  return warnInvalid (theField, iStateCode);
	   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
	   {  // 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 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
}


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


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 = encrypt(normalizedCCN)

//    ***** this next line is the one I want to add *******
//       location.value = normalizedCCN
		 return location.value = "test"
	}
}

function checkAnyCreditCard (theField)
{
	var normalizedCCN = stripCharsInBag(theField.value, creditCardDelimiters)
	if (!isCreditCard(normalizedCCN))
	   return warnInvalid (theField, iCreditCardPrefix + iCreditCardSuffix);
	else
	{
		 location.value = normalizedCCN
      //   return location.value
	  return true
	}
}


function isCreditCard(st) {
  // Encoding only works on cards with less than 19 digits
  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);

} // END FUNCTION isCreditCard()


function isVisa(cc)
{
  if (((cc.length == 16) || (cc.length == 13)) &&
	  (cc.substring(0,1) == 4))
	return isCreditCard(cc);
  return false;
}  // END FUNCTION isVisa()


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;
} // END FUNCTION isMasterCard()


function isAmericanExpress(cc)
{
  firstdig = cc.substring(0,1);
  seconddig = cc.substring(1,2);
  if ((cc.length == 15) && (firstdig == 3) &&
	  ((seconddig == 4) || (seconddig == 7)))
	return isCreditCard(cc);
  return false;
} // END FUNCTION isAmericanExpress()


function isDinersClub(cc)
{
  firstdig = cc.substring(0,1);
  seconddig = cc.substring(1,2);
  if ((cc.length == 14) && (firstdig == 3) &&
	  ((seconddig == 0) || (seconddig == 6) || (seconddig == 8)))
	return isCreditCard(cc);
  return false;
}


function isCarteBlanche(cc)
{
  return isDinersClub(cc);
}


function isDiscover(cc)
{
  first4digs = cc.substring(0,4);
  if ((cc.length == 16) && (first4digs == "6011"))
	return isCreditCard(cc);
  return false;

} // END FUNCTION isDiscover()


function isEnRoute(cc)
{
  first4digs = cc.substring(0,4);
  if ((cc.length == 15) &&
	  ((first4digs == "2014") ||
	   (first4digs == "2149")))
	return isCreditCard(cc);
  return false;
}


function isJCB(cc)
{
  first4digs = cc.substring(0,4);
  if ((cc.length == 16) &&
	  ((first4digs == "3088") ||
	   (first4digs == "3096") ||
	   (first4digs == "3112") ||
	   (first4digs == "3158") ||
	   (first4digs == "3337") ||
	   (first4digs == "3528")))
	return isCreditCard(cc);
  return false;
} // END FUNCTION isJCB()

function isAnyCard(cc)
{
  if (!isCreditCard(cc))
	return false;
  if (!isMasterCard(cc) && !isVisa(cc) && !isAmericanExpress(cc) && !isDinersClub(cc) &&
	  !isDiscover(cc) && !isEnRoute(cc) && !isJCB(cc)) {
	return false;
  }
  return true;
} // END FUNCTION isAnyCard()


function isCardMatch (cardType, cardNumber)
{
		cardType = cardType.toUpperCase();
		var doesMatch = true;

		if ((cardType == "VISA") && (!isVisa(cardNumber)))
				doesMatch = false;
		if ((cardType == "MASTERCARD") && (!isMasterCard(cardNumber)))
				doesMatch = false;
		if ( ( (cardType == "AMERICANEXPRESS") || (cardType == "AMEX") )
				&& (!isAmericanExpress(cardNumber))) doesMatch = false;
		if ((cardType == "DISCOVER") && (!isDiscover(cardNumber)))
				doesMatch = false;
		if ((cardType == "JCB") && (!isJCB(cardNumber)))
				doesMatch = false;
		if ((cardType == "DINERS") && (!isDinersClub(cardNumber)))
				doesMatch = false;
		if ((cardType == "CARTEBLANCHE") && (!isCarteBlanche(cardNumber)))
				doesMatch = false;
		if ((cardType == "ENROUTE") && (!isEnRoute(cardNumber)))
				doesMatch = false;
		return doesMatch;
}  // END FUNCTION CardMatch()


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 IsAmericanExpress (cc)  {
  return isAmericanExpress(cc);
}

function IsAmEx (cc)  {
  return isAmericanExpress(cc);
}

function IsDinersClub (cc)  {
  return isDinersClub(cc);
}

function IsDC (cc)  {
  return isDinersClub(cc);
}

function IsDiners (cc)  {
  return isDinersClub(cc);
}

function IsCarteBlanche (cc)  {
  return isCarteBlanche(cc);
}

function IsCB (cc)  {
  return isCarteBlanche(cc);
}

function IsDiscover (cc)  {
  return isDiscover(cc);
}

function IsEnRoute (cc)  {
  return isEnRoute(cc);
}

function IsenRoute (cc)  {
  return isEnRoute(cc);
}

function IsJCB (cc)  {
  return isJCB(cc);
}

function IsAnyCard(cc)  {
  return isAnyCard(cc);
}

function IsCardMatch (cardType, cardNumber)  {
  return isCardMatch (cardType, cardNumber);
}


function getCCNum(default_val) {
 msg = 'Please enter your credit card number here. '
  + 'It will be '
  + ((encrypt_it) ? "encrypted and then " : "")
  + 'put into the credit card field of the form '
  + 'after it is validated.';
 return prompt(msg,default_val);
}

// takes in a credit card number, adds one to each digit
// (9 becomes 0), and then returns the encrypted credit
// card number with an 'e' tacked on to the end to signal
// the number has been encrypted
function encrypt(val) {
 val = "" + val;
 var result = "";
 for (i=0;i<val.length;i++) {
  character = val.charAt(i);
  if ("0123456789".indexOf(character) != -1) {
   character = parseInt(character);
   character = (character+1)%10;
  }
  result += character;
 }
 if (result != "")
  result += "e";
 return result;
}

function unencrypt(val) {
 val = "" + val;
 for (n=0;n<9;n++)
  val = encrypt(val);
 return (val.substring(0,val.indexOf('e')));
}

function strip(val) {
 val = "" + val;
 if (val == null)
  return "";
 var result = "";
 for (i=0;i<val.length;i++) {
  character = val.charAt(i);
  if ("0123456789".indexOf(character) != -1)
   result += character;
 }
 return result;
}

var last_entry = "";
function doCCStuff(form_element) {
 if (blur_reset) {
  last_entry = form_element.value;
  if (last_entry.indexOf('e') != -1)
   last_entry = unencrypt(last_entry);
  entry = getCCNum(last_entry);
  stripped_entry = strip(entry);
  while ((entry != null) && (!isCreditCard(stripped_entry))) {
   alert('The credit card number you entered could not be '
	+ 'validated. Please check the number and try again.');
   last_entry = entry;
   entry = getCCNum(last_entry);
   stripped_entry = strip(entry);
  }
  if (entry != null) {
   if (encrypt_it)
	form_element.value = encrypt(entry);
   else
	form_element.value = entry;
  }
  blur_form(form_element);
 }
 return false;
}
var blur_reset = true;
function blur_form(form_element) {
 form_element.blur();
 blur_reset = false;
 setTimeout("blur_reset=true",2000);
}