Angularjs checkbox фильтр, как сделать кнопку сброса выборок

(function () {'use strict'; 
 
angular. 
  module('myApp', []). 
  controller('WineCtrl', WineCtrl); 
 
// Functions - Definitions 
function WineCtrl() { 
  // Variables - Private 
  var self = this; 
   
  // Variables - Public 
  self.filter = {}; 
  self.wines = [ 
    {name: 'Wine A', category: 'red'}, 
    {name: 'Wine B', category: 'red'}, 
    {name: 'Wine C', category: 'white'}, 
    {name: 'Wine D', category: 'red'}, 
    {name: 'Wine E', category: 'red'}, 
    {name: 'Wine F', category: 'white'}, 
    {name: 'Wine G', category: 'champagne'}, 
    {name: 'Wine H', category: 'champagne'}     
  ]; 
   
  // Functions - Public 
  self.filterByCategory = filterByCategory; 
  self.getCategories = getCategories; 
   
  // Functions - Definitions 
  function filterByCategory(wine) { 
    return self.filter[wine.category] || noFilter(self.filter); 
  } 
     
  function getCategories() { 
    return (self.wines || []). 
      map(function (wine) { return wine.category; }). 
      filter(function (cat, idx, arr) { return arr.indexOf(cat) === idx; }); 
  } 
 
  function noFilter(filterObj) { 
    return Object. 
      keys(filterObj). 
      every(function (key) { return !filterObj[key]; }); 
  } 
} 
 
}());

<script src="https://code.angularjs.org/1.5.7/angular.min.js"></script> 
<div ng-app="myApp"> 
  <div ng-controller="WineCtrl as ctrl"> 
    <h3>Categories</h3> 
    <div ng-repeat="category in ctrl.getCategories()"> 
      <label> 
        <input type="checkbox" ng-model="ctrl.filter[category]" /> 
        {{ category }} 
      </label> 
    </div> 
    <hr /> 
    <h3>Available Wines</h3> 
    <div ng-repeat="wine in (ctrl.wines | filter:ctrl.filterByCategory) as filteredWines"> 
      {{ wine.name }} <i>({{ wine.category }})</i> 
    </div> 
    <hr /> 
    <b>Number of results: {{ filteredWines.length }}</b> 
  </div> 
</div>