AngularJS clear input fields

var app = angular.module('plunker', ['clear-input']);


(function() {
    'use strict';

    angular.module('clear-input', []);

    angular.module('clear-input').directive('clearable', clearable);

    function clearable() {
        var directive = {
            restrict: 'A',
            require: 'ngModel',
            link: link
        };
        return directive;

        function link(scope, elem, attrs, ctrl) {
            elem.addClass('clearable');

            elem.bind('input', function() {
                elem[toggleClass(elem.val())]('x');
            });

            elem.on('mousemove', function(e) {
                if(elem.hasClass('x')) {
                    elem[toggleClass(this.offsetWidth - 25 < e.clientX - this.getBoundingClientRect().left)]('onX');
                }
            });

            elem.on('click', function(e) {
                if(elem.hasClass('onX')) {
                    elem.removeClass('x onX').val(undefined);
                    ctrl.$setViewValue(undefined);
                    ctrl.$render();
                    scope.$digest();
                }
            });

            function toggleClass(v) {
                return v ? 'addClass' : 'removeClass';
            }
        }
    }



    var style = document.createElement('style');
    style.type = 'text/css';
    style.innerHTML =
        '.clearable {' +
        'background-image: url(data:image/gif;base64,R0lGODlhBwAHAIAAAP///5KSkiH5BAAAAAAALAAAAAAHAAcAAAIMTICmsGrIXnLxuDMLADs=);' +
        'background-repeat: no-repeat;' +
        'background-attachment: initial;' +
        'background-position: right -10px center;' +
        '}' +
        '.clearable.x {' +
        'transition: background 0.4s;' +
        'background-position: right 10px center;' +
        '}' +
        '.clearable.onX {' +
        'cursor: pointer;' +
        '}';

    document.getElementsByTagName('head')[0].appendChild(style);


})();

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.4.x" src="https://code.angularjs.org/1.4.0/angular.js" data-semver="1.4.0"></script>
    <script src="app.js"></script>
  </head>

  <body>
    <div>
      <p>Input field</p>
      <input type="text" data-ng-model="input" clearable>
    </div>
     <div>
      <p>Textarea</p>
      <textarea data-ng-model="textarea" clearable></textarea>
    </div>
  </body>

</html>

/* Put your css in here */