(function ( $ ) {
      $.fn.mutarSelect = function( options ){
  
  
          // This is the easiest way to have default options.
          var settings = $.extend({
          valueselector:"Agregar nuevo",
          }, options );

          var father = $(this).attr("id");
          $(this).append("<option value='' class='mutarselect-add'>" + settings.valueselector + "</option>");

          $("#" + father + " .mutarselect-add").click(function( event ){

                  event.preventDefault();

                  $("#" + father + " .mutarselect-rm" ).remove();

                  $(this).parent("#" + father).hide();
                                 
                  $("<input type='text' placeholder='nuevo valor' autofocus autocomplete=off' class='mutarselect-input " + father +"' >").insertAfter( $(this).parent(".mutarselect") );

          });    

             
          $("form").on("keypress", ".mutarselect-input",function( event ){
              if ( event.keyCode == '13' ){
                  event.preventDefault();
  
                  $(this).prev(".mutarselect").prepend("<option selected=\"selected\" value='" + $(this).val()  + "' class='mutarselect-rm'>" + $(this).val() + "</option>");
                  $(this).prev(".mutarselect").show();
                  $(this).remove();
                  
              }
          });

  
        $("form").on("focusout", ".mutarselect-input",function( event ){
                  $(this).prev(".mutarselect").prepend("<option selected=\"selected\" value='" + $(this).val()  + "' class='mutarselect-rm'>" + $(this).val() + "</option>");
                  $(this).prev(".mutarselect").show();
                  $(this).remove();
  
          });

          //return this;
  
      };
  }( jQuery ));