// JavaScript Document

/*--------[ CC validation ]-------------*/
var Cards = new makeArray(8);
Cards[0] = new CardType("MasterCard", "51,52,53,54,55", "16");
var MasterCard = Cards[0];
Cards[1] = new CardType("VisaCard", "4", "13,16");
var VisaCard = Cards[1];
Cards[2] = new CardType("AmExCard", "34,37", "15");
var AmExCard = Cards[2];
Cards[3] = new CardType("DinersClubCard", "30,36,38", "14");
var DinersClubCard = Cards[3];
Cards[4] = new CardType("DiscoverCard", "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();

function CheckCardNumber(form) {
	var tmpyear;
	if (form.card_number.value.length == 0) {
		alert("Please enter a Card Number.");
		form.card_number.focus();
		return false;
	}
	var card_expiration = form.card_expiration_m.value +'/'+ form.card_expiration_y.value;
	if (card_expiration.length == 0) {
		alert("Please enter the Expiration Date.");
		form.card_expiration_m.focus();
		return false;
	}
	temporal_date = card_expiration.split('/');
	tmpyear = temporal_date[1];
	tmpmonth = temporal_date[0];
	if (!(new CardType()).isExpiryDate(tmpyear, tmpmonth)) {
		alert("This card has already expired.");
		return false;
	}
	card = form.card_type.options[form.card_type.selectedIndex].value;
	var retval = eval(card + ".checkCardNumber(\"" + form.card_number.value + "\", " + tmpyear + ", " + tmpmonth + ");");
	cardname = "";
	if (retval) {
//		alert("This card number appears to be valid.");
		return true;
	}
	else {
		for (var n = 0; n < Cards.size; n++) {
			if (Cards[n].checkCardNumber(form.card_number.value, tmpyear, tmpmonth)) {
				cardname = Cards[n].getCardType();
				break;
			}
		}
		if (cardname.length > 0) {
			alert("This looks like a " + cardname + " number, not a " + card + " number.");
		}
		else {
			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;
	this.setCardType = setCardType;
	this.setLen = setLen;
	this.setRules = setRules;
	this.setExpiryDate = setExpiryDate;
	
	this.setCardType(tmpcardtype);
	this.setLen(tmplen);
	this.setRules(tmprules);
	if (argc > 4)
	this.setExpiryDate(argv[3], argv[4]);
	
	this.checkCardNumber = checkCardNumber;
	this.getExpiryDate = getExpiryDate;
	this.getCardType = getCardType;
	this.isCardNumber = isCardNumber;
	this.isExpiryDate = isExpiryDate;
	this.luhnCheck = luhnCheck;
	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;
}

function getCardType() {
	return this.cardtype;
}

function getExpiryDate() {
	return this.month + "/" + this.year;
}

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;
}

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;
}

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;
}

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;
}

function makeArray(size) {
	this.size = size;
	return this;
}

function setCardNumber(cardnumber) {
	this.cardnumber = cardnumber;
	return this;
}

function setCardType(cardtype) {
	this.cardtype = cardtype;
	return this;
}

function setExpiryDate(year, month) {
	this.year = year;
	this.month = month;
	return this;
}

function setLen(len) {
	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;
}

function setRules(rules) {
	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;
}
/*--------[ CC validation end ]-------------*/