<!-- Version: 3.00 -->

var digits = "0123456789";
var whitespace = " \t\n\r";
var iPhone = "This field must be a Phone number (like (415) 555-1212). Please re-enter it now."
var iEmail = "This field must be a valid email address (like foo@bar.com). Please re-enter it now."
var iDatePrefix = "The Month, and Year for "
var iDateSuffix = " do not form a valid date.  Please reenter them now."
var defaultEmptyOK = false

function warnInvalid (theField, s)
{   theField.focus()
    theField.select()
    alert(s)
    return false
}

function checkPhone(theField, emptyOK)
{   if (checkPhone.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else
    {  if (!isPhoneNumber(stripCharsNotInBag(theField.value,digits), false)) 
          return warnInvalid (theField, iPhone);
       else return true;
    }
}

function isPhoneNumber(s)
{   if (isEmpty(s)) 
       if (isPhoneNumber.arguments.length == 1) return defaultEmptyOK;
       else return (isPhoneNumber.arguments[1] == true);
    return (isPositiveInteger(s) && s.length > 9)
}

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 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 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 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 isDigit(c)
{   return ((c >= "0") && (c <= "9"))
}

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 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 checkDate(dateField, labelString)
{   var dateString = stripCharsNotInBag(dateField.value, digits);
    if (!isMonth(dateString.substring(0,2))) return warnInvalid(dateField,iDatePrefix + labelString + iDateSuffix);
    if (!isYear(dateString.substring(2,4))) return warnInvalid(dateField,iDatePrefix + labelString + iDateSuffix);
    dateField.value=dateString.substring(0,2) +"/" +dateString.substring(2,4);
    return true
}

function checkEmail(theField, emptyOK, lWarn)
{   
    if (checkEmail.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && ((isEmpty(theField.value) || (theField.value=="null")))) return true;
    else if (!isEmail(theField.value, false)) 
		{
			if (checkEmail.arguments.length == 3)
			{
				if (lWarn)
			       return warnInvalid(theField, iEmail);
				else
					return false;
			}
			else
				return warnInvalid(theField, iEmail);
		}
    else return true;
}

function isEmail(s, emptyOK)
{   if (isEmpty(s)) 
       if (isEmail.arguments.length == 1) return defaultEmptyOK;
       else return (isEmail.arguments[1] == true);
    // is s whitespace?
    if (isWhitespace(s)) return false;
    // there must be >= 1 character before @, so we
    // start looking at character position 1 
    // (i.e. second character)
    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 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 is whitespace.
        var c = s.charAt(i);

        if (whitespace.indexOf(c) != -1) return true;
    }

    // No characters are whitespace.
    return false;
}

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;
}





var creditCardDelimiters = " "
var iCreditCardPrefix = "This is not a valid"
var iCreditCardSuffix = " credit card number.  Please reenter it now."

function checkCreditCard(theField)
{   var normalizedCCN = stripCharsNotInBag(theField.value, digits);
    if (!isAnyCard(normalizedCCN)) 
       return warnInvalid(theField, iCreditCardPrefix + iCreditCardSuffix);
    else 
    {  theField.value = normalizedCCN
       return true
    }
}

function isAnyCard(cCCN)
{
	return (isVisa(cCCN) || isMasterCard(cCCN) || isAmericanExpress(cCCN) || isDiscover(cCCN))
}

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--;
  }
  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 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;
}

function isDiscover(cc)
{
  first4digs = cc.substring(0,4);
  if ((cc.length == 16) && (first4digs == "6011"))
    return isCreditCard(cc);
  return false;
}