// FormChek.js
//
// SUMMARY
//
// This is a set of JavaScript functions for validating input on 
// an HTML form.  Functions are provided to validate:
//
//      - U.S. and international phone/fax numbers
//      - U.S. Postal Codes (2 letter abbreviations for names of states)
//      - email addresses
//	- dates (entry of year, month, and day and validity of combined date)
//	- credit card numbers
//
// Supporting utility functions validate that:
//
//      - characters are Letter, Digit, or LetterOrDigit
//      - strings are a Signed, Positive, Negative, Nonpositive, or
//        Nonnegative integer
//      - strings are a Float or a SignedFloat
//      - strings are Alphabetic, Alphanumeric, or Whitespace
//      - strings contain an integer within a specified range
//
// Functions are also provided to interactively check the
// above kinds of data and prompt the user if they have
// been entered incorrectly.
//
// Other utility functions are provided to:
//
// 	- remove from a string characters which are/are not 
//	  in a "bag" of selected characters	
// 	- reformat a string, adding delimiter characters
//	- strip whitespace/leading whitespace from a string
//        Security numbers
//
//
// Many of the below functions take an optional parameter eok (for "emptyOK")
// which determines whether the empty string will return true or false.
// Default behavior is controlled by global variable defaultEmptyOK.
//
// BASIC DATA VALIDATION FUNCTIONS:
//
// isWhitespace (s)                    Check whether string s is empty or whitespace.
// isLetter (c)                        Check whether character c is an English letter 
// isDigit (c)                         Check whether character c is a digit 
// isLetterOrDigit (c)                 Check whether character c is a letter or digit.
// isInteger (s [,eok])                True if all characters in string s are numbers.
// isSignedInteger (s [,eok])          True if all characters in string s are numbers; leading + or - allowed.
// isPositiveInteger (s [,eok])        True if string s is an integer > 0.
// isNonnegativeInteger (s [,eok])     True if string s is an integer >= 0.
// isNegativeInteger (s [,eok])        True if s is an integer < 0.
// isNonpositiveInteger (s [,eok])     True if s is an integer <= 0.
// isFloat (s [,eok])                  True if string s is an unsigned floating point (real) number. (Integers also OK.)
// isSignedFloat (s [,eok])            True if string s is a floating point number; leading + or - allowed. (Integers also OK.)
// isAlphabetic (s [,eok])             True if string s is English letters 
// isAlphanumeric (s [,eok])           True if string s is English letters and numbers only.
// 
// isUSPhoneNumber (s [,eok])          True if string s is a valid U.S. Phone Number. 
// isInternationalPhoneNumber (s [,eok]) True if string s is a valid international phone number.
// isStateCode (s [,eok])              True if string s is a valid U.S. Postal Code
// isEmail (s [,eok])                  True if string s is a valid email address.
// isYear (s [,eok])                   True if string s is a valid Year number.
// isIntegerInRange (s, a, b [,eok])   True if string s is an integer between a and b, inclusive.
// isMonth (s [,eok])                  True if string s is a valid month between 1 and 12.
// isDay (s [,eok])                    True if string s is a valid day between 1 and 31.
// daysInFebruary (year)               Returns number of days in February of that year.
// isDate (year, month, day)           True if string arguments form a valid date.


// FUNCTIONS TO REFORMAT DATA:
//
// stripCharsInBag (s, bag)            Removes all characters in string bag from string s.
// stripCharsNotInBag (s, bag)         Removes all characters NOT in string bag from string s.
// stripWhitespace (s)                 Removes all whitespace characters from s.
// stripInitialWhitespace (s)          Removes initial (leading) whitespace characters from s.
// reformat (TARGETSTRING, STRING,     Function for inserting formatting characters or
//   INTEGER, STRING, INTEGER ... )       delimiters into TARGETSTRING.                                       


// FUNCTIONS TO PROMPT USER:
//
// prompt (s)                          Display prompt string s in status bar.
// promptEntry (s)                     Display data entry prompt string s in status bar.
// warnEmpty (theField, s)             Notify user that required field theField is empty.
// warnInvalid (theField, s)           Notify user that contents of field theField are invalid.


// FUNCTIONS TO INTERACTIVELY CHECK FIELD CONTENTS:
//
// checkStringLength (theField, s, n [,eok])    Check that theField.value is less than n chars.
// checkString (theField, s [,eok])    Check that theField.value is not empty or all whitespace.
// checkStateCode (theField)           Check that theField.value is a valid U.S. state code.
// checkZIPCode (theField [,eok])      Check that theField.value is a valid ZIP code.
// checkUSPhone (theField [,eok])      Check that theField.value is a valid US Phone.
// checkInternationalPhone (theField [,eok])  Check that theField.value is a valid International Phone.
// checkEmail (theField [,eok])        Check that theField.value is a valid Email.
// checkYear (theField [,eok])         Check that theField.value is a valid Year.
// checkMonth (theField [,eok])        Check that theField.value is a valid Month.
// checkDay (theField [,eok])          Check that theField.value is a valid Day.
// checkDate (yearField, monthField, dayField, labelString, OKtoOmitDay)
//                                     Check that field values form a valid date.
// getRadioButtonValue (radio)         Get checked value from radio button.
// checkCreditCard (radio, theField)   Validate credit card info.


// CREDIT CARD DATA VALIDATION FUNCTIONS
// 
// isCreditCard (st)              True if credit card number passes the Luhn Mod-10 test.
// isVisa (cc)                    True if string cc is a valid VISA number.
// isMasterCard (cc)              True if string cc is a valid MasterCard number.
// isAmericanExpress (cc)         True if string cc is a valid American Express number.
// isDinersClub (cc)              True if string cc is a valid Diner's Club number.
// isCarteBlanche (cc)            True if string cc is a valid Carte Blanche number.
// isDiscover (cc)                True if string cc is a valid Discover card number.
// isEnRoute (cc)                 True if string cc is a valid enRoute card number.
// isJCB (cc)                     True if string cc is a valid JCB card number.
// isAnyCard (cc)                 True if string cc is a valid card number for any of the accepted types.
// isCardMatch (Type, Number)     True if Number is valid for credic card of type Type.
//
// Other stub functions are retained for backward compatibility with LivePayment code.
// See comments below for details.
//
// Performance hint: when you deploy this file on your website, strip out the
// comment lines from the source code as well as any of the functions which
// you don't need.  This will give you a smaller .js file and achieve faster
// downloads.
//
// 18 Feb 97 created Eric Krock
// Original JavaScript 1.0-only version (works on Nav2.x and higher)
// available at http://developer.netscape.com/library/examples/javascript/formval/overview.html
// 
// 4 Nov 97 rewritten to demonstrate use of JavaScript 1.2 regular expressions.
// (code is simpler and shorter but works on Nav4.x and higher only)
//
// (c) 1997 Netscape Communications Corporation




// REGULAR EXPRESSION DECLARATIONS
// Notes which apply to all the regexps below:
// (1) We want to only match strings exactly. In other words,
//     we only want to return true if the string being tested
//     matches the regular expression with no leading or trailing
//     unmatched characters. So, we begin each regexp with
//     the special character ^ (which matches beginning of input)
//     and end each regexp with the special character $ (which
//     matches end of input).
// (2) In the below comments we use these abbreviations:
//     BOI = Beginning Of Input
//     EOI = End Of Input
// (3) For explanations of the regexp special characters such as
//     ^ $ \s + [] \d * ! ? \ .
//     see http://developer.netscape.com/library/documentation/communicator/jsguide/regexp.htm


// BOI, followed by one or more whitespace characters, followed by EOI.
var reWhitespace = /^\s+$/


// BOI, followed by one lower or uppercase English letter, followed by EOI.
var reLetter = /^[a-zA-Z]$/


// BOI, followed by one or more lower or uppercase English letters, 
// followed by EOI.
var reAlphabetic = /^[a-zA-Z]+$/


// BOI, followed by one or more lower or uppercase English letters
// or digits, followed by EOI.
var reAlphanumeric = /^[a-zA-Z0-9]+$/


// BOI, followed by one digit, followed by EOI.
var reDigit = /^\d/


// BOI, followed by one lower or uppercase English letter
// or digit, followed by EOI.
var reLetterOrDigit = /^([a-zA-Z]|\d)$/


// BOI, followed by one or more digits, followed by EOI.
var reInteger = /^\d+$/


// BOI, followed by an optional + or -, followed by one or more digits, 
// followed by EOI.
var reSignedInteger = /^(\+|-)?\d+$/


// BOI, followed by one of these two patterns:
// (a) one or more digits, followed by ., followed by zero or more digits
// (b) zero or more digits, followed by ., followed by one or more digits
// ... followed by EOI.
var reFloat = /^((\d+(\.\d*)?)|((\d*\.)?\d+))$/


// BOI, followed by an optional + or -, followed by one of these two patterns:
// (a) one or more digits, followed by ., followed by zero or more digits
// (b) zero or more digits, followed by ., followed by one or more digits
// ... followed by EOI.
var reSignedFloat = /^(((\+|-)?\d+(\.\d*)?)|((\+|-)?(\d*\.)?\d+))$/

// BOI, followed by one or more characters, followed by @,
// followed by one or more characters, followed by ., 
// followed by one or more characters, followed by EOI.
var reEmail = /^.+\@.+\..+$/




// VARIABLE DECLARATIONS

var digits = "0123456789";

var lowercaseLetters = "abcdefghijklmnopqrstuvwxyz"

var uppercaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

// whitespace characters as defined by this sample code
var whitespace = " \t\n\r";


// 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 + "+";





var sCreditCardNumber = "Credit Card Number"
var sOtherInfo = "Other Information"

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



// i is an abbreviation for "invalid"

var iEmail = "This field must be a valid email address (like joe@myisp.com). Please reenter it now."

var iNonnegativeInteger = "This field must be a number greater than zero without decimal points."


// 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 94043)."
var pUSPhone = "10 digit U.S. phone number (like 415 555 1212)."
var pWorldPhone = "international phone number."
var pEmail = "valid email address (like foo@bar.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


function makeArray(n) {
   return new Array();
}



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)

{   // Is s empty?
    return (isEmpty(s) || reWhitespace.test(s));
}



// Removes all characters which appear in regexp bag from string s.
// NOTES:
// 1) bag must be a regexp which matches single characters in isolation,
//    i.e. A or B or C or D or 1 or 2 ...
//    e.g. /\d/g  or /[a-zA-Z]/g
// 2) make sure to append the 'g' modifier (for global search & replace)
//    at the end of the regexp
//    e.g. /\d/g  or /[a-zA-Z]/g

function stripCharsInRE (s, bag)

{       return s.replace(bag, "")
}



// 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)
}




// WORKAROUND FUNCTION FOR NAVIGATOR 2.0.2 COMPATIBILITY.
//
// The below function *should* be unnecessary.  In general,
// avoid using it.  Use the standard method indexOf instead.
//
// However, because of an apparent bug in indexOf on 
// Navigator 2.0.2, the below loop does not work as the
// body of stripInitialWhitespace:
//
// while ((i < s.length) && (whitespace.indexOf(s.charAt(i)) != -1))
//   i++;
//
// ... so we provide this workaround function charInString
// instead.
//
// charInString (CHARACTER c, STRING s)
//
// Returns true if single character c (actually a string)
// is contained within string s.

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



// Removes initial (leading) whitespace characters from s.
// Global variable whitespace (see above)
// defines which characters are considered whitespace.

function stripInitialWhitespace (s)

{   var i = 0;

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

    return s.substring (i, s.length);
}

// Removes leading & trailing whitespace characters from s.
// Global variable whitespace (see above)
// defines which characters are considered whitespace.

function trim (s)
{
    var i = 0;
    while ((i < s.length) && charInString (s.charAt(i), whitespace))
       i++;
    s = s.substring (i, s.length);
    i = s.length-1;
    while ((i > 0) && charInString (s.charAt(i), whitespace))
        i--;
    return s.substring(0, i+1);
}

// Returns true if character c is an English letter 
// (A .. Z, a..z).
//
// NOTE: Need i18n version to support European characters.
// This could be tricky due to different character
// sets and orderings for various languages and platforms.

function isLetter (c)
{   return reLetter.test(c)
}



// Returns true if character c is a digit 
// (0 .. 9).

function isDigit (c)
{   return reDigit.test(c)
}



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

function isLetterOrDigit (c)
{   return reLetterOrDigit.test(c)
}



// isInteger (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if all characters in string s are numbers.
//
// Accepts non-signed integers only. Does not accept floating 
// point, exponential notation, etc.
//
// We don't use parseInt because that would accept a string
// with trailing non-numeric characters.
//
// By default, returns defaultEmptyOK if s is empty.
// There is an optional second argument called emptyOK.
// emptyOK is used to override for a single function call
//      the default behavior which is specified globally by
//      defaultEmptyOK.
// If emptyOK is false (or any value other than true), 
//      the function will return false if s is empty.
// If emptyOK is true, the function will return true if s is empty.
//
// EXAMPLE FUNCTION CALL:     RESULT:
// isInteger ("5")            true 
// isInteger ("")             defaultEmptyOK
// isInteger ("-5")           false
// isInteger ("", true)       true
// isInteger ("", false)      false
// isInteger ("5", false)     true

function isInteger (s)

{   var i;

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

    return reInteger.test(s)
}
// isSignedInteger (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if all characters are numbers; 
// first character is allowed to be + or - as well.
//
// Does not accept floating point, exponential notation, etc.
//
// We don't use parseInt because that would accept a string
// with trailing non-numeric characters.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.
//
// EXAMPLE FUNCTION CALL:          RESULT:
// isSignedInteger ("5")           true 
// isSignedInteger ("")            defaultEmptyOK
// isSignedInteger ("-5")          true
// isSignedInteger ("+5")          true
// isSignedInteger ("", false)     false
// isSignedInteger ("", true)      true

function isSignedInteger (s)

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


    else {
       return reSignedInteger.test(s)
    }
}




// isPositiveInteger (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if string s is an integer > 0.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isPositiveInteger (s)
{   var secondArg = defaultEmptyOK;

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

    // The next line is a bit byzantine.  What it means is:
    // a) s must be a signed integer, AND
    // b) one of the following must be true:
    //    i)  s is empty and we are supposed to return true for
    //        empty strings
    //    ii) this is a positive, not negative, number

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






// isNonnegativeInteger (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if string s is an integer >= 0.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isNonnegativeInteger (s)
{   var secondArg = defaultEmptyOK;

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

    // The next line is a bit byzantine.  What it means is:
    // a) s must be a signed integer, AND
    // b) one of the following must be true:
    //    i)  s is empty and we are supposed to return true for
    //        empty strings
    //    ii) this is a number >= 0

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

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


// isNegativeInteger (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if string s is an integer < 0.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isNegativeInteger (s)
{   var secondArg = defaultEmptyOK;

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

    // The next line is a bit byzantine.  What it means is:
    // a) s must be a signed integer, AND
    // b) one of the following must be true:
    //    i)  s is empty and we are supposed to return true for
    //        empty strings
    //    ii) this is a negative, not positive, number

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






// isNonpositiveInteger (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if string s is an integer <= 0.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isNonpositiveInteger (s)
{   var secondArg = defaultEmptyOK;

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

    // The next line is a bit byzantine.  What it means is:
    // a) s must be a signed integer, AND
    // b) one of the following must be true:
    //    i)  s is empty and we are supposed to return true for
    //        empty strings
    //    ii) this is a number <= 0

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




function checkFloat(theField, labelString, emptyOK)
{
   if (!isFloat(theField.value, emptyOK))
   {
       return warnInvalid(theField, labelString + ' must be a positive decimal number');
   }
   return true;
}

// isFloat (STRING s [, BOOLEAN emptyOK])
// 
// True if string s is an unsigned floating point (real) number. 
//
// Also returns true for unsigned integers. If you wish
// to distinguish between integers and floating point numbers,
// first call isInteger, then call isFloat.
//
// Does not accept exponential notation.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isFloat (s)

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

    return reFloat.test(s)
}







// isSignedFloat (STRING s [, BOOLEAN emptyOK])
// 
// True if string s is a signed or unsigned floating point 
// (real) number. First character is allowed to be + or -.
//
// Also returns true for unsigned integers. If you wish
// to distinguish between integers and floating point numbers,
// first call isSignedInteger, then call isSignedFloat.
//
// Does not accept exponential notation.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isSignedFloat (s)

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

    else {
       return reSignedFloat.test(s)
    }
}




// isAlphabetic (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if string s is English letters 
// (A .. Z, a..z) only.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.
//
// NOTE: Need i18n version to support European characters.
// This could be tricky due to different character
// sets and orderings for various languages and platforms.

function isAlphabetic (s)

{   var i;

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

    else {
       return reAlphabetic.test(s)
    }
}




// isAlphanumeric (STRING s [, BOOLEAN emptyOK])
// 
// Returns true if string s is English letters 
// (A .. Z, a..z) and numbers only.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.
//
// NOTE: Need i18n version to support European characters.
// This could be tricky due to different character
// sets and orderings for various languages and platforms.

function isAlphanumeric (s)

{   var i;

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

    else {
       return reAlphanumeric.test(s)
    }
}




// reformat (TARGETSTRING, STRING, INTEGER, STRING, INTEGER ... )       
//
// Handy function for arbitrarily inserting formatting characters
// or delimiters of various kinds within TARGETSTRING.
//
// reformat takes one named argument, a string s, and any number
// of other arguments.  The other arguments must be integers or
// strings.  These other arguments specify how string s is to be
// reformatted and how and where other strings are to be inserted
// into it.
//
// reformat processes the other arguments in order one by one.
// * If the argument is an integer, reformat appends that number 
//   of sequential characters from s to the resultString.
// * If the argument is a string, reformat appends the string
//   to the resultString.
//
// NOTE: The first argument after TARGETSTRING must be a string.
// (It can be empty.)  The second argument must be an integer.
// Thereafter, integers and strings must alternate.  This is to
// provide backward compatibility to Navigator 2.0.2 JavaScript
// by avoiding use of the typeof operator.
//
// It is the caller's responsibility to make sure that we do not
// try to copy more characters from s than s.length.
//
// EXAMPLES:
//
// * To reformat a 10-digit U.S. phone number from "1234567890"
//   to "(123) 456-7890" make this function call:
//   reformat("1234567890", "(", 3, ") ", 3, "-", 4)
//
// * To reformat a 9-digit U.S. Social Security number from
//   "123456789" to "123-45-6789" make this function call:
//   reformat("123456789", "", 3, "-", 2, "-", 4)
//
// HINT:
//
// If you have a string which is already delimited in one way
// (example: a phone number delimited with spaces as "123 456 7890")
// and you want to delimit it in another way using function reformat,
// call function stripCharsNotInBag to remove the unwanted 
// characters, THEN call function reformat to delimit as desired.
//
// EXAMPLE:
//
// reformat (stripCharsNotInBag ("123 456 7890", digits),
//           "(", 3, ") ", 3, "-", 4)

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;
}




// isUSPhoneNumber (STRING s [, BOOLEAN emptyOK])
// 
// isUSPhoneNumber returns true if string s is a valid U.S. Phone
// Number.  Must be 10 digits.
//
// NOTE: Strip out any delimiters (spaces, hyphens, parentheses, etc.)
// from string s before calling this function.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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)
}




// isInternationalPhoneNumber (STRING s [, BOOLEAN emptyOK])
// 
// isInternationalPhoneNumber returns true if string s is a valid 
// international phone number.  Must be digits only; any length OK.
// May be prefixed by + character.
//
// NOTE: A phone number of all zeros would not be accepted.
// I don't think that is a valid phone number anyway.
//
// NOTE: Strip out any delimiters (spaces, hyphens, parentheses, etc.)
// from string s before calling this function.  You may leave in 
// leading + character if you wish.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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




// isZIPCode (STRING s [, BOOLEAN emptyOK])
// 
// isZIPCode returns true if string s is a valid 
// U.S. ZIP code.  Must be 5 or 9 digits only.
//
// NOTE: Strip out any delimiters (spaces, hyphens, etc.)
// from string s before calling this function.  
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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)))
}





// isStateCode (STRING s [, BOOLEAN emptyOK])
// 
// Return true if s is a valid U.S. Postal Code 
// (abbreviation for state).
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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) )
}




// isEmail (STRING s [, BOOLEAN emptyOK])
// 
// Email address must be of form a@b.c -- in other words:
// * there must be at least one character before the @
// * there must be at least one character before and after the .
// * the characters @ and . are both required
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function isEmail (s)

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

    else {
       return reEmail.test(s)
    }
}



// isYear (STRING s [, BOOLEAN emptyOK])
// 
// isYear returns true if string s is a valid 
// Year number.  Must be 2 or 4 digits only.
// 
// For Year 2000 compliance, you are advised
// to use 4-digit year numbers everywhere.
//
// And yes, this function is not Year 10000 compliant, but 
// because I am giving you 8003 years of advance notice,
// I don't feel very guilty about this ...
//
// For B.C. compliance, write your own function. ;->
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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));
}



// isIntegerInRange (STRING s, INTEGER a, INTEGER b [, BOOLEAN emptyOK])
// 
// isIntegerInRange returns true if string s is an integer 
// within the range of integer arguments a and b, inclusive.
// 
// For explanation of optional argument emptyOK,
// see comments of function isInteger.


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

    // Catch non-integer strings to avoid creating a NaN below,
    // which isn't available on JavaScript 1.0 for Windows.
    if (!isInteger(s, false)) return false;

    // Now, explicitly change the type to integer via parseInt
    // so that the comparison code below will work both on 
    // JavaScript 1.2 (which typechecks in equality comparisons)
    // and JavaScript 1.1 and before (which doesn't).
    var num = parseInt (s, 10);
    return ((num >= a) && (num <= b));
}



// isMonth (STRING s [, BOOLEAN emptyOK])
// 
// isMonth returns true if string s is a valid 
// month number between 1 and 12.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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

    return isIntegerInRange (s, 1, 12);
}



// isDay (STRING s [, BOOLEAN emptyOK])
// 
// isDay returns true if string s is a valid 
// day number between 1 and 31.
// 
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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



// daysInFebruary (INTEGER year)
// 
// Given integer argument year,
// returns number of days in February of that year.

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 );
}



// isDate (STRING year, STRING month, STRING day)
//
// isDate returns true if string arguments year, month, and day 
// form a valid date.
// 

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

    // catch invalid days, except for February
    if (intDay > daysInMonth[intMonth]) return false; 
    if ((intMonth == 2) && (intDay > daysInFebruary(intYear))) return false;

    return true;
}


// Notify user that required field theField is empty.
// String s describes expected contents of theField.value.
// Put focus in theField and return false.

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



// Notify user that contents of field theField are invalid.
// String s describes expected contents of theField.value.
// Put select theField, pu focus in it, and return false.

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

// Notify user that contents of the field has exceeded the max length
// of n characters. 
// String s describes expected contents of theField.value.
// Put select theField, pu focus in it, and return false.

function warnLength(theField, s, n) {
    theField.focus()
    theField.select()
    alert('Field ' + s + ' has exceeded the maximum of ' + n + ' characters. Please shorten it and re-submit the form.')
    return false
}


/* FUNCTIONS TO INTERACTIVELY CHECK VARIOUS FIELDS. */

//
// checkConfirmFields (TEXTFIELD tf1, TEXTFIELD tf2, string s)
// check if the value in the two fields is the same 
//

function checkConfirmFields(tf1, tf2, s) {
    if (tf1.value != tf2.value) {
        return warnInvalid(tf2, s + ' and Confirm ' + s + ' do not match.');
    }
    return true;
}

//
// checkStringLength (TEXTFIELD theField, STRING s, INTEGER n[, BOOLEAN emptyOK==false])
// check if string s is less than n chars
//
function checkStringLength (theField, s, n, emptyOK)
{   // Next line is needed on NN3 to avoid "undefined is not a number" error
    // in equality comparison below.
    if (checkStringLength.arguments.length == 3) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    if (isWhitespace(theField.value) && emptyOK == false) {
        return warnEmpty (theField, s);
    }
    if (theField.value.length > n)
        return warnLength (theField, s, n);
    else return true;
}

//
// Arr : array of (TEXTFIELD, STRING, INTEGER max, emptyOK)
// Check if string is less than max and also empty or not depending on the
// value of emptyOK
//
function checkStringLengthInArr(l)
{
    for (var i = 0; i < l.length ; i++) {
        if (!checkStringLength(l[i][0], l[i][1], l[i][2], l[i][3])) {
            return false;
        }
    }
    return true;
}

// checkString (TEXTFIELD theField, STRING s, [, BOOLEAN emptyOK==false])
//
// Check that string theField.value is not all whitespace.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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;
}

//
// checkString
//
//

// checkStateCode (TEXTFIELD theField [, BOOLEAN emptyOK==false])
//
// Check that string theField.value is a valid U.S. state code.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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;
    }
}



// checkEmail (TEXTFIELD theField [, BOOLEAN emptyOK==false])
//
// Check that string theField.value is a valid Email.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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;
}

// Check that string theField.value is a valid Year.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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;
}


// Check that string theField.value is a valid Month.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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;
}


// Check that string theField.value is a valid Day.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

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;
}



// checkDate (yearField, monthField, dayField, STRING labelString [, OKtoOmitDay==false])
//
// Check that yearField.value, monthField.value, and dayField.value 
// form a valid date.
//
// If they don't, labelString (the name of the date, like "Birth Date")
// is displayed to tell the user which date field is invalid.
//
// If it is OK for the day field to be empty, set optional argument
// OKtoOmitDay to true.  It defaults to false.

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
}




// Validate credit card info.

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
    }
}

// form -- Form
// selectedElementName -- Name of select list element
// value -- Value of the selected elelment
function setSelected (form, selectedElementName, value) {
    var j = 0;
    var elem = findElement(form, selectedElementName);
    if (elem != null) {
        for (j = 0; j < elem.options.length; j++) {
            if (elem.options[j].value == value) {
                elem.selectedIndex = j;
                return;
            }
        }
    } else {
        alert("No element " + selectedElementName + " found");
    }
}

function getSelectedValue (form, elementName) {
    var elem = findElement(form, elementName);
    if (elem != null) {
        return elem.options[elem.selectedIndex].value;
    } else {
        alert("No element " + elementName + " found");
    }
}

function getValue (form, elementName) {
    var elem = findElement(form, elementName);
    if (elem != null) {
        return elem.value;
    } else {
        alert("No element " + elementName + " found");
    }
}

function findElement(form, elementName) {
        return form[elementName];
}

function setValue(form, elementName, value) {
    var elem = findElement(form, elementName);
    if (elem != null) {
        elem.value = value;
    } else {
        alert("No element " + elementName + " found");
    }
}

function submitAction(form) {
    var act = getSelectedValue(form, "actionLink");
    if (act == '') {
        alert("Please select an action");
        return false;
    }
    form.action = act;
    return true;
}

// This method is required to set the window.location.href property as
// it requires a fully qualified href
// href = action.pl?name=NGD
// returns : http://cvs.celoxis.com/cgi-bin/action.pl?name=NGD
//
function relativeToAbsolute (relative) {
    
    var proto = window.location.protocol;
    var host  = window.location.host;
    var base  = window.location.pathname;
    var npath = base.replace(/[^\/]+$/,relative);
    return proto + '//' + host + npath;
}
function doNothing() {}

//
// A generic popup function to popup windows

// **************************************************
// IE : title must not have any special characters like spaces, so not used
// **************************************************
function popUp(url, title, h, w, options) {
  if (options == null || (trim(options) == "")) {
    options = "directories=no,scrollbars=yes,location=no,menubar=no,personalbar=no,resizable=yes,toolbar=no";
  }
  window.open(url, title, "width=" + w + ",height=" + h + "," + options);
}
function getRadioSelection(radio)
{
    var value = null;
    if (radio.length == null)
    {
       // not an array, happens when only one radio button exists
        if (radio.checked) {
            value = radio.value;
        }
    } else {
        for (var i = 0; i < radio.length; i++) {
            if (radio[i].checked) { value = radio[i].value; }
        }
    }
    return value;
}

function checkSelectorSelection(select, s)
{
    var v = getSelectedValue(select.form, select.name);
    if (isEmpty(v))
    {
        alert(s + " is a required field. Please make a selection");
        return false;
    }
    return true;
}

// Check if radio button is selected
function checkRadioSelection(radio, s)
{
    var isChecked = false;
    if (radio.length == null)
    {
        // not an array, happens when only one radio button exists
        isChecked = radio.checked;
    } else {
        for (var i = 0; i < radio.length; i++) {
            if (radio[i].checked) { isChecked = true; }
        }
    }
    if (!isChecked) {
        if (!s)
        {
          alert("Please make a selection");
        }
        else
        {
           alert(s + " is a required field. Please make a selection");
        }
        return false;
    }
    return true;
}

//
// A function to decode a string encoded as a:b:c where each is encoded using
// radix 36
//
function decodeInt(val, separator)
{
  var parts = val.split(separator);
  if (parts == null || parts.length == 0) return new Array(0);

  var ids = new Array(parts.length);
  for (var i = 0; i < parts.length; i++) {
    ids[i] = parseInt(parts[i], 36);
  }
  return ids;
}

//
// Sets the checkbox to be selected or unselected
// Useful when we need CheckAll/UncheckAll feature
//
function setCheckboxState(formName, elementName, checked)
{
    var form = document.forms[formName];
    var len = form.elements.length;
    var i=0;
    for(i=0; i<len; i++) {
      var element = form.elements[i];
      if (element.name == elementName) {
        element.checked = checked;
      }
    }
}

function checkCheckboxSelection(checkbox, message)
{
    var isChecked = false;
    if (checkbox.length == null)
    {
        // not an array, happens when only one checkbox button exists
        isChecked = checkbox.checked;
    } else {
        for (var i = 0; i < checkbox.length; i++) {
            if (checkbox[i].checked) { isChecked = true; }
        }
    }
    if (!isChecked) {
        if(message)
            alert (message);
        else
            alert("Please Make A Selection");
        return false;
    }
    return true;
}

//
// Returns an ARRAY of values
//
function getCheckboxSelection(formName,checkboxName)
{
    var ret = new Array();
    var form = document.forms[formName];
    var len = form.elements.length;
    var i=0;
    for(i=0; i<len; i++) {
      var element = form.elements[i];
      if (element.name == checkboxName) 
      {
          if (element.checked)
          {
             ret.push(element.value); 
          }
      }
    }
    return ret;
}

////////////////////////////////////////////////////////////////////////


function getElementBy (elemTag)     // name OR id
        {
        var elem = document.getElementById (elemTag);
        
        if (elem)
            return elem;

        var elems = document.getElementsByName (elemTag);

        if (elems.length > 0)
            return elems[0];
        
        return null;
        }

    function closeElem(elemName)
        {
        var elem = getElementBy (elemName);
        
        if (elem)
            elem.style.display = "none";
        }

    function openElem(elemName)
        {
        var elem = getElementBy (elemName);
        
        if (elem)
            elem.style.display = "";
        }

    function openCloseElem(elemName, doOpen)
        {
        var elem = getElementBy (elemName);
        
        if (!elem)
            return false;
        
        if (doOpen)
            elem.style.display = "";
        else
            elem.style.display = "none";
        
        return doOpen;
        }



    function hideShowElem(elemName, doShow)
        {
        if (doShow)
            getElementBy (elemName).style.visibility = "visible";
        else
            getElementBy (elemName).style.visibility = "hidden";
        }

    function hideElem(elemName)
        {
        getElementBy (elemName).style.visibility = "hidden";
        }

    function showElem(elemName)
        {
        getElementBy (elemName).style.visibility = "visible";
        }