/********************************************************************************************************************

Function:    PaymentCardType
Description: Decodes the type of payment card from Visa, Mastercard, AMEX, etc.
Parameters:  A string indicating the type of payment card, or a blank string if not identified. 

*********************************************************************************************************************/
create or replace function PaymentCardType(cardNumber string)
  returns string 
  language javascript
  strict
  as '
     
    //Remove all spaces and dashes. Simply ignore them.
    NUMBER = CARDNUMBER.replace(/ /g, "");
    NUMBER = NUMBER.replace(/-/g, "");
     
     
    // Visa
    var re = new RegExp("(4[0-9]{15})");
    if (NUMBER.match(re) != null)
        return "Visa";

    // Mastercard
    re = new RegExp("(5[1-5][0-9]{14})");
    if (NUMBER.match(re) != null)
        return "Mastercard";

    // AMEX
    re = new RegExp("^3[47]");
    if (NUMBER.match(re) != null)
        return "AMEX";

    // Discover
    re = new RegExp("^(6011|622(12[6-9]|1[3-9][0-9]|[2-8][0-9]{2}|9[0-1][0-9]|92[0-5]|64[4-9])|65)");
    if (NUMBER.match(re) != null)
        return "Discover";

    // Diners
    re = new RegExp("^36");
    if (NUMBER.match(re) != null)
        return "Diners";

    // Diners - Carte Blanche
    re = new RegExp("^30[0-5]");
    if (NUMBER.match(re) != null)
        return "Diners - Carte Blanche";

    // JCB
    re = new RegExp("^35(2[89]|[3-8][0-9])");
    if (NUMBER.match(re) != null)
        return "JCB";

    // Visa Electron
    re = new RegExp("^(4026|417500|4508|4844|491(3|7))");
    if (NUMBER.match(re) != null)
        return "Visa Electron";

    return "";
 
  ';

-- Test the UDF:
select PaymentCardType('4470653497431234');