function doDiv(dname) {
	dname.style.visibility=true;
	}

function prepCC() {
	var Cards = new makeArray(8);
	Cards[0] = new CardType("MasterCard", "51,52,53,54,55", "16");
	var MasterCard = Cards[0];
	Cards[1] = new CardType("Visa", "4", "13,16");
	var VisaCard = Cards[1];
	Cards[2] = new CardType("American Express", "34,37", "15");
	var AmExCard = Cards[2];
	Cards[3] = new CardType("DinersClubCard", "30,36,38", "14");
	var DinersClubCard = Cards[3];
	Cards[4] = new CardType("Discover", "6011", "16");
	var DiscoverCard = Cards[4];
	Cards[5] = new CardType("enRouteCard", "2014,2149", "15");
	var enRouteCard = Cards[5];
	Cards[6] = new CardType("JCBCard", "3088,3096,3112,3158,3337,3528", "16");
	var JCBCard = Cards[6];
	var LuhnCheckSum = Cards[7] = new CardType();
}

/*************************************************************************\
CheckCardNumber(form)
function called when users click the "check" button.
\*************************************************************************/
function CheckCardNumber(form) {
var tmpyear;
if (form.ccnum.value.length == 0) {
alert("Please enter a Card Number.");
form.ccnum.focus();
return false;
}
if (form.cvv.value.length == 0) {
alert("Please enter a Card Security Code.");
form.cvv.focus();
return false;
}
tmpyear = form.ccexpyear.options[form.ccexpyear.selectedIndex].value;
tmpmonth = form.ccexpmonth.options[form.ccexpmonth.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.cctype.options[form.cctype.selectedIndex].value;
//alert("Luhn Next");
var lval = luhnCheck(form.ccnum.value);
if (lval) {
	//alert("Luhn passed: " + lval);
	}
else {
	alert("Please check your card number, it is not valid.");
	return false;
}
//alert("Now, on to the card type");
//alert(card + ".checkCardNumber(\"" + form.ccnum.value + "\", " + tmpyear + ", " + tmpmonth + ");");
//var retval = eval("checkCardNumber(\"" + form.ccnum.value + "\", " + tmpyear + ", " + tmpmonth + ");");
//alert("Retval: " + retval);
cardname = "";
//if (retval) {
// comment this out if used on an order form
//alert("This card number appears to be valid.");
//return false;
//}
//else {
//alert("This card number appears to be valid.");

// The cardnumber has the valid luhn checksum, but we want to know which
// cardtype it belongs to.
//for (var n = 0; n < Cards.size; n++) {
//if (Cards[n].checkCardNumber(form.ccnum.value, tmpyear, tmpmonth)) {
//cardname = Cards[n].getCardType();
//break;
//   }
//}

var cnum = form.ccnum.value;
//alert("cnum = " + cnum + "\nCard Type: " + card);
var c = form.ccnum.value.substring(1,0);
//alert(c);
if (c == "5" && card == "MasterCard") {
	//alert("Found MasterCard");
	return true;
	}
if (c == "4" && card == "Visa") {
        //alert("Found Visa");
        return true;
        }
if (c == "3" && card == "American Express") {
        //alert("Found American Express");
        return true;
        }
if (c == "6" && card == "Discover") {
        //alert("Found Discover");
        return true;
        }

// Not a valid card
alert("Sorry, your card number and card type could not be validated.");
return false;

//if (cardname.length > 0) {
//alert("This looks like a " + cardname + " number, not a " + card + " number.");
//return false;
//}
//else {
//alert("This card number is not valid.");
//return false;
//      }
//   }
}
/*************************************************************************\
Object CardType([String cardtype, String rules, String len, int year, 
                                        int month])
cardtype    : type of card, eg: MasterCard, Visa, etc.
rules       : rules of the cardnumber, eg: "4", "6011", "34,37".
len         : valid length of cardnumber, eg: "16,19", "13,16".
year        : year of expiry date.
month       : month of expiry date.
eg:
var VisaCard = new CardType("Visa", "4", "16");
var AmExCard = new CardType("American Express", "34,37", "15");
\*************************************************************************/
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;
}

/*************************************************************************\
boolean checkCardNumber([String cardnumber, int year, int month])
return true if cardnumber pass the luhncheck and the expiry date is
valid, else return false.
\*************************************************************************/
function checkCardNumber() {
alert("Checking card number now...");
var argv = checkCardNumber.arguments;
var argc = checkCardNumber.arguments.length;
var cardnumber = (argc > 0) ? argv[0] : this.cardnumber;
alert("Card Number: " + 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;
}