Credit card detection jquery plugin. Saving from permanent deletion.

jquery.card-detective.js

/**
 * Card Detective jQuery Plugin
 *
 * Author       : Tyler Childs
 * Email        : [email protected]
 *
 * Purpose      : Automatically detect a credit card value based on user input
 *
 * Usage        :
 *
 *      $( selector ).CardDetective();
 *          Ex. $("#card_number").CardDetective();
 *
 *
 *
 * Options      :
 *
 *      {
 *          detected: function,         // function that will fire when card type has changed
 *          cards: $( selector ),       // selectors  that will be toggled active/inactive
 *          tests: [ { regex, string }] // array of objects with regular expression and card type string.
 *      }
 *
 *
 *
 */

(function ( $ ) {

  $.fn.CardDetective = function( options ) {

    var settings = $.extend({
      detected: cardChanged,
      cards: $('.card-image'),
      tests: [
        {
          regex: new RegExp("^5[1-5]"),
          type: "mastercard"
        },
        {
          regex: new RegExp("^4"),
          type: "visa"
        },
        {
          regex: new RegExp("^3[47]"),
          type: "amex"
        },
        {
          regex: new RegExp("^6(?:011|5)"),
          type: "discover"
        }
      ]
    }, options );

    function getCreditCardType( event ) {

      var $this = event.data.elem;
      var accountNumber = $this.val();
      var type = $this.data("type");

      $this.data("type", "unknown");

      for(var i = 0; i < settings.tests.length; i++){
        if (settings.tests[i].regex.test(accountNumber)){
          $this.data("type", settings.tests[i].type);
          break;
        }
      }

      // Card Updated
      if( $this.data("type") != type ){

        // fire event and pass in the card type
        $( window ).trigger( "card-detected", [ $this.data("type") ] );
      }
    }

    function cardChanged( event, type ){
      var $cards = event.data.cards;

      if(type === "unknown"){
          $cards.removeClass('inactive active');
      } else {
          $cards.addClass('inactive');
          $('.'+ type).toggleClass('inactive active');
      }

      var cvv_length = type === "amex" ? 4 : 3;
      $cvv = $("input[name='cvv2']");
      $cvv.rules("remove", "minlength maxlength");
      $cvv.rules("add", { minlength: cvv_length, maxlength: cvv_length});
    }

    this.each(function() {
      $(this).on('keyup', { elem: $(this), test: 'string' }, getCreditCardType).data("type", "unknown");
      $( window ).on('card-detected', { cards: settings.cards }, settings.detected);
    });

    return this;
  };

}( jQuery ));