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 Visa = Cards[1];
Cards[2] = new cardtype("AmericanExpress", "34,37", "15");
var AmericanExpress = Cards[2];
Cards[3] = new cardtype("DinersClubCard", "30,36,38", "14");
var DinersClubCard = Cards[3];
Cards[4] = new cardtype("Discover", "6011", "16");
var Discover = 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
//   PURPOSE: 
//----------------------------------------------------------------------------
function CheckCardNumber() 
{
	var tmpyear;
	
	card = document.forms[0].cardtype.options[document.forms[0].cardtype.selectedIndex].value;
	if (card == "None") {
		alert("Please enter a valid Card Type.");
		document.forms[0].cardtype.focus();
		return false;
	}
	
	if (document.forms[0].cardnum.value.length == 0) {
		alert("Please enter a Card Number.");
		document.forms[0].cardnum.focus();
		return false;
	}

	tmpyear = document.forms[0].expyear.options[document.forms[0].expyear.selectedIndex].value;
	tmpmonth = document.forms[0].expmonth.options[document.forms[0].expmonth.selectedIndex].value;
	
	if (tmpyear == 0 || tmpmonth == 0) {
		alert("Please enter a valid Expiration Date.");
		document.forms[0].expmonth.focus();
		return false;
	}
	
	if (!(new cardtype()).isExpiryDate(tmpyear, tmpmonth)) {
		alert("This card has already expired.");
		return false;
	}


	var retval = eval(card + ".checkCardNumber(\"" + document.forms[0].cardnum.value +
	"\", " + tmpyear + ", " + tmpmonth + ");");
	cardname = "";

	if (retval)
		// comment this out if used on an order form
		//alert("This card number appears to be valid.");
		return true;
	else {
		// The cardnum 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(document.forms[0].cardnum.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.");
		}
	}
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: cardtype
//   PURPOSE: 
//  cardtype: type of card, eg: MasterCard, Visa, etc.
//     rules: rules of the cardnum, eg: "4", "6011", "34,37".
//       len: valid length of cardnum, eg: "16,19", "13,16".
//      year: year of expiry date.
//     month: month of expiry date.
//----------------------------------------------------------------------------
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.setcardnum = setcardnum;  // set cardnum 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;  // checkcardnum method.
	this.getExpiryDate = getExpiryDate;  // getExpiryDate method.
	this.getcardtype = getcardtype;  // getcardtype method.
	this.iscardnum = iscardnum;  // iscardnum method.
	this.isExpiryDate = isExpiryDate;  // isExpiryDate method.
	this.luhnCheck = luhnCheck;// luhnCheck method.
	
	return this;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: checkCardNumber
//   PURPOSE: Return true if cardnum pass the luhncheck and the expiry date is
//            valid, else return false
//----------------------------------------------------------------------------
function checkCardNumber() 
{
	var argv = checkCardNumber.arguments;
	var argc = checkCardNumber.arguments.length;
	var cardnum = (argc > 0) ? argv[0] : this.cardnum;
	var year = (argc > 1) ? argv[1] : this.year;
	var month = (argc > 2) ? argv[2] : this.month;

	this.setcardnum(cardnum);
	this.setExpiryDate(year, month);

	if (!this.iscardnum())
		return false;
		
	if (!this.isExpiryDate())
		return false;

	return true;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: getcardtype
//   PURPOSE: 
//----------------------------------------------------------------------------
function getcardtype() 
{
	return this.cardtype;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: getExpiryDate
//   PURPOSE: 
//----------------------------------------------------------------------------
function getExpiryDate() 
{
	return this.month + "/" + this.year;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: iscardnum
//   PURPOSE: Return true if cardnum pass the luhncheck and the rules, else return
//----------------------------------------------------------------------------
function iscardnum() 
{
	var argv = iscardnum.arguments;
	var argc = iscardnum.arguments.length;
	
	var cardnum = (argc > 0) ? argv[0] : this.cardnum;
	if (!this.luhnCheck())
		return false;

	for (var n = 0; n < this.len.size; n++)
		if (cardnum.toString().length == this.len[n]) 
		{
			for (var m = 0; m < this.rules.size; m++) 
			{
				var headdigit = cardnum.substring(0, this.rules[m].toString().length);
				if (headdigit == this.rules[m])
					return true;
			}
			return false;
		}
	return false;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: isExpiryDate
//   PURPOSE: Return true if the date is a valid expiry date
//----------------------------------------------------------------------------
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
//   PURPOSE: Return true if argvalue contains only numeric characters
//----------------------------------------------------------------------------
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
//   PURPOSE: Return true if cardnum 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 cardnum = argc > 0 ? argv[0] : this.cardnum;

	if (! isNum(cardnum)) 
		return false;

	var no_digit = cardnum.length;
	var oddoeven = no_digit & 1;
	var sum = 0;

	for (var count = 0; count < no_digit; count++) 
	{
		var digit = parseInt(cardnum.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
//   PURPOSE: 
//----------------------------------------------------------------------------
function makeArray(size) 
{
	this.size = size;
	return this;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: setcardnumber
//   PURPOSE: 
//----------------------------------------------------------------------------
function setcardnum(cardnum) 
{
	this.cardnum = cardnum;
	return this;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: setcardtype
//   PURPOSE: 
//----------------------------------------------------------------------------
function setcardtype(cardtype) 
{
	this.cardtype = cardtype;
	return this;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: setExpiryDate
//   PURPOSE: 
//----------------------------------------------------------------------------
function setExpiryDate(year, month) 
{
	this.year = year;
	this.month = month;
	return this;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: setLen
//   PURPOSE: 
//----------------------------------------------------------------------------
function setLen(len) 
{
	
	if (len.length == 0 || len == null)		// Create the len array.
		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
//   PURPOSE: 
//----------------------------------------------------------------------------
function setRules(rules) 
{
	if (rules.length == 0 || rules == null)		// Create the rules array.
		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;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION:  isEmpty
//   PURPOSE:  Check whether string s is empty
//----------------------------------------------------------------------------
function isEmpty(s)
{   
	return ((s == null) || (s.length == 0))
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION:  isWhitespace
//   PURPOSE:  Returns true if string s is empty or whitespace characters only
//----------------------------------------------------------------------------
function isWhitespace (s)
{
   var i;
   var whitespace = " \t\n\r";

    // 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 isn't whitespace.
        var c = s.charAt(i);

        if (whitespace.indexOf(c) == -1) return false;
    }

    // All characters are whitespace.
    return true;
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: isNumber
//   PURPOSE: To determine if each char in the passed string is a number
//----------------------------------------------------------------------------
function isNumber(str) 
{
	numdecs = 0
	for (i = 0; i < str.length; i++) {
		mychar = str.charAt(i)
		if ((mychar >= "0" && mychar <= "9") || mychar == "." || mychar == "$") {
			if (mychar == ".")
				numdecs++
		}
		else 
			return false
	}
	if (numdecs > 1)
		return false	
return true
}
//----------------------------------------------------------------------------


//----------------------------------------------------------------------------
//  FUNCTION: Valid_Date
//   PURPOSE: Checks to make sure that a valid date has been entered
//----------------------------------------------------------------------------
function Valid_Date(datein)
{
	        
	var indate=datein;

	if (indate.indexOf("-")!=-1)
	{
		var sdate = indate.split("-")
	} else {
		var sdate = indate.split("/")
	}

	var chkDate=new Date(Date.parse(indate))
	var cmpDate=(chkDate.getMonth()+1)+"/"+(chkDate.getDate())+"/"+(chkDate.getYear())
	var indate2=(Math.abs(sdate[0]))+"/"+(Math.abs(sdate[1]))+"/"+(Math.abs(sdate[2]))

	if (indate2!=cmpDate)
	{
		alert("You've entered an invalid date or date format.  Please use the (MM/DD/YY) or (MM/DD/YYYY) format.");
		return false;
	} else {
		if (cmpDate=="NaN/NaN/NaN")
		{
			alert("You've entered an invalid date or date format.  Please use the (MM/DD/YY) or (MM/DD/YYYY) format.");
			return false;
		} else {
			return true;
		}       
	}

}
//----------------------------------------------------------------------------



//***************************************************************************
//  FUNCTION:	IsValidEmailAddress
//   PURPOSE:	Returns TRUE if the input paramater is a valid email address
//***************************************************************************
function IsValidEmailAddress(sEmail) 
{

	if (isWhitespace(sEmail) == true)
		return false
	else {
		var at="@"
		var dot="."
		var lat=sEmail.indexOf(at)
		var lstr=sEmail.length
		var ldot=sEmail.indexOf(dot)
				
		if (sEmail.indexOf(at)==-1)
		   return false

		if (sEmail.indexOf(at)==-1 || sEmail.indexOf(at)==0 || sEmail.indexOf(at)==lstr)
		   return false

		if (sEmail.indexOf(dot)==-1 || sEmail.indexOf(dot)==0 || sEmail.indexOf(dot)==lstr)
		    return false

		 if (sEmail.indexOf(at,(lat+1))!=-1)
		    return false

		 if (sEmail.substring(lat-1,lat) == dot || sEmail.substring(lat+1,lat+2) == dot)
		    return false

		 if (sEmail.indexOf(dot,(lat+2)) == -1)
		    return false
				
		 if (sEmail.indexOf(" ")!=-1)
		    return false

		 return true
	}
}
//***************************************************************************