repeating.js

(function($, undefined) {

  'use strict';

  function Repeating(container) {
    this.container = $(container);
    this.template = this.items().first().clone();
    this.template.find('input, select, textarea').val('');
  }

  Repeating.prototype = {
    items: function() {
      return this.container.find('[data-repeating-item]');
    },

    recount: function() {
      this.items().each(function(index) {
        $('input, select, textarea').attr({
          id: function(i, value) {
            return value.replace(/_\d+_/, '_' + index + '_');
          },

          name: function(i, value) {
            return value.replace(/\[\d+\]/, '[' + index + ']');
          }
        });
      });
    },

    remove: function(child) {
      $(child).parents('[data-repeating-item]').remove();
    },

    add: function() {
      this.container.append(this.template.clone());
    },
  };

  $.fn.repeating = function() {
    return this.each(function() {
      new Repeating(this);
    });
  };

  $('[data-repeating-container]').repeating();

})(this.jQuery);