<!--- Validate Card --->
var Cards = new makeArray(8);
Cards[0] = new CardType("MC", "51,52,53,54,55", "16");
var MC = Cards[0];
Cards[1] = new CardType("VISA", "4", "13,16");
var VISA = Cards[1];
Cards[2] = new CardType("AMEX", "34,37", "15");
var AMEX = Cards[2];
Cards[3] = new CardType("SWITCH");
var SWITCH = Cards[3];
Cards[4] = new CardType("LASER");
var LASER = Cards[4];
var LuhnCheckSum = Cards[7] = new CardType();

/*************************************************************************\
CheckCardNumber(form)
function called when users click the "check" button.
\*************************************************************************/
function CheckCardNumber(form) {
if (form.ConfirmTermsAndConditions.checked == false) {
alert("Please confirm that you have read the Terms and Conditions.");
form.CardNumber.focus();
return false;
}

var tmpyear;
if (form.CardNumber.value.length == 0) {
alert("Please enter a Card Number.");
form.CardNumber.focus();
return false;
}
if (form.ExpYear.value.length == 0) {
alert("Please enter the Expiration Year.");
form.ExpYear.focus();
return false;
}
if (form.ExpYear.value > 96)
tmpyear = "19" + form.ExpYear.value;
else if (form.ExpYear.value < 21)
tmpyear = "20" + form.ExpYear.value;
else {
alert("The Expiration Year is not valid.");
return false;
}
tmpmonth = form.ExpMon.options[form.ExpMon.selectedIndex].value;
// The following line doesn't work in IE3, you need to change it
// to something like "(new CardType())...".
// if (!CardType().isExpiryDate(tmpyear, tmpmonth)) {
if (!(new CardType()).isExpiryDate(tmpyear, tmpmonth)) {
alert("This card has already expired.");
return false;
}


card = form.CardType.options[form.CardType.selectedIndex].value;
if (card == "MC" && document.ThisForm.SecurityCode.value == "") {
alert("Please enter security code.");
form.CardType.focus();
return false;
}

card = form.CardType.options[form.CardType.selectedIndex].value;
if (card == "VISA" && document.ThisForm.SecurityCode.value == "") {
alert("Please enter security code.");
form.CardType.focus();
return false;
}


card = form.CardType.options[form.CardType.selectedIndex].value;
var retval = eval(card + ".checkCardNumber(\"" + form.CardNumber.value +
"\", " + tmpyear + ", " + tmpmonth + ");");
cardname = "";
if (retval)

return true;


else {
// The CardNumber has the valid luhn checksum, but we want to know which
// cardtype it belongs to.
alert("This card number is not valid.");
return false;
   }
  
   
}


function CardType() {
var n;
var argv = CardType.arguments;
var argc = CardType.arguments.length;

this.objname = "object CardType";

var tmpcardtype = (argc > 0) ? argv[0] : "CardObject";
var tmprules = (argc > 1) ? argv[1] : "0,1,2,3,4,5,6,7,8,9";
var tmplen = (argc > 2) ? argv[2] : "13,14,15,16,19";

this.setCardNumber = setCardNumber;  // set CardNumber method.
this.setCardType = setCardType;  // setCardType method.
this.setLen = setLen;  // setLen method.
this.setRules = setRules;  // setRules method.
this.setExpiryDate = setExpiryDate;  // setExpiryDate method.

this.setCardType(tmpcardtype);
this.setLen(tmplen);
this.setRules(tmprules);
if (argc > 4)
this.setExpiryDate(argv[3], argv[4]);

this.checkCardNumber = checkCardNumber;  // checkCardNumber method.
this.getExpiryDate = getExpiryDate;  // getExpiryDate method.
this.getCardType = getCardType;  // getCardType method.
this.isCardNumber = isCardNumber;  // isCardNumber method.
this.isExpiryDate = isExpiryDate;  // isExpiryDate method.
this.luhnCheck = luhnCheck;// luhnCheck method.
return this;
}



function checkCardNumber() {
var argv = checkCardNumber.arguments;
var argc = checkCardNumber.arguments.length;
var CardNumber = (argc > 0) ? argv[0] : this.CardNumber;
var year = (argc > 1) ? argv[1] : this.year;
var month = (argc > 2) ? argv[2] : this.month;

this.setCardNumber(CardNumber);
this.setExpiryDate(year, month);

if (!this.isCardNumber())
return false;
if (!this.isExpiryDate())
return false;

return true;
}
/*************************************************************************\
String getCardType()
return the cardtype.
\*************************************************************************/
function getCardType() {
return this.cardtype;
}
/*************************************************************************\
String getExpiryDate()
return the expiry date.
\*************************************************************************/
function getExpiryDate() {
return this.month + "/" + this.year;
}
/*************************************************************************\
boolean isCardNumber([String CardNumber])
return true if CardNumber pass the luhncheck and the rules, else return
false.
\*************************************************************************/
function isCardNumber() {
var argv = isCardNumber.arguments;
var argc = isCardNumber.arguments.length;
var CardNumber = (argc > 0) ? argv[0] : this.CardNumber;
if (!this.luhnCheck())
return false;

for (var n = 0; n < this.len.size; n++)
if (CardNumber.toString().length == this.len[n]) {
for (var m = 0; m < this.rules.size; m++) {
var headdigit = CardNumber.substring(0, this.rules[m].toString().length);
if (headdigit == this.rules[m])
return true;
}
return false;
}
return false;
}

/*************************************************************************\
boolean isExpiryDate([int year, int month])
return true if the date is a valid expiry date,
else return false.
\*************************************************************************/
function isExpiryDate() {
var argv = isExpiryDate.arguments;
var argc = isExpiryDate.arguments.length;

year = argc > 0 ? argv[0] : this.year;
month = argc > 1 ? argv[1] : this.month;

if (!isNum(year+""))
return false;
if (!isNum(month+""))
return false;
today = new Date();
expiry = new Date(year, month);
if (today.getTime() > expiry.getTime())
return false;
else
return true;
}

/*************************************************************************\
boolean isNum(String argvalue)
return true if argvalue contains only numeric characters,
else return false.
\*************************************************************************/
function isNum(argvalue) {
argvalue = argvalue.toString();

if (argvalue.length == 0)
return false;

for (var n = 0; n < argvalue.length; n++)
if (argvalue.substring(n, n+1) < "0" || argvalue.substring(n, n+1) > "9")
return false;

return true;
}

/*************************************************************************\
boolean luhnCheck([String CardNumber])
return true if CardNumber pass the luhn check else return false.
Reference: http://www.ling.nwu.edu/~sburke/pub/luhn_lib.pl
\*************************************************************************/
function luhnCheck() {
var argv = luhnCheck.arguments;
var argc = luhnCheck.arguments.length;

var CardNumber = argc > 0 ? argv[0] : this.CardNumber;

if (! isNum(CardNumber)) {
return false;
  }

var no_digit = CardNumber.length;
var oddoeven = no_digit & 1;
var sum = 0;

for (var count = 0; count < no_digit; count++) {
var digit = parseInt(CardNumber.charAt(count));
if (!((count & 1) ^ oddoeven)) {
digit *= 2;
if (digit > 9)
digit -= 9;
}
sum += digit;
}
if (sum % 10 == 0)
return true;
else
return false;
}

/*************************************************************************\
ArrayObject makeArray(int size)
return the array object in the size specified.
\*************************************************************************/
function makeArray(size) {
this.size = size;
return this;
}

/*************************************************************************\
CardType setCardNumber(CardNumber)
return the CardType object.
\*************************************************************************/
function setCardNumber(CardNumber) {
this.CardNumber = CardNumber;
return this;
}

/*************************************************************************\
CardType setCardType(cardtype)
return the CardType object.
\*************************************************************************/
function setCardType(cardtype) {
this.cardtype = cardtype;
return this;
}

/*************************************************************************\
CardType setExpiryDate(year, month)
return the CardType object.
\*************************************************************************/
function setExpiryDate(year, month) {
this.year = year;
this.month = month;
return this;
}

/*************************************************************************\
CardType setLen(len)
return the CardType object.
\*************************************************************************/
function setLen(len) {
// Create the len array.
if (len.length == 0 || len == null)
len = "13,14,15,16,19";

var tmplen = len;
n = 1;
while (tmplen.indexOf(",") != -1) {
tmplen = tmplen.substring(tmplen.indexOf(",") + 1, tmplen.length);
n++;
}
this.len = new makeArray(n);
n = 0;
while (len.indexOf(",") != -1) {
var tmpstr = len.substring(0, len.indexOf(","));
this.len[n] = tmpstr;
len = len.substring(len.indexOf(",") + 1, len.length);
n++;
}
this.len[n] = len;
return this;
}

/*************************************************************************\
CardType setRules()
return the CardType object.
\*************************************************************************/
function setRules(rules) {
// Create the rules array.
if (rules.length == 0 || rules == null)
rules = "0,1,2,3,4,5,6,7,8,9";
  
var tmprules = rules;
n = 1;
while (tmprules.indexOf(",") != -1) {
tmprules = tmprules.substring(tmprules.indexOf(",") + 1, tmprules.length);
n++;
}
this.rules = new makeArray(n);
n = 0;
while (rules.indexOf(",") != -1) {
var tmpstr = rules.substring(0, rules.indexOf(","));
this.rules[n] = tmpstr;
rules = rules.substring(rules.indexOf(",") + 1, rules.length);
n++;
}
this.rules[n] = rules;
return this;
}
//  End -->