Angular File Upload - Crea la directiva file-model con soporte para envio de multipart y dependencia de jqueryfilestyle. La directiva ng-model NO banca file uploads

multipart.js

(function(){

    angular
        .module('FileUploads', [])
        .factory('FileUploads.FormDataBuilder', ['$window', function(window) {
            return function(data) {
                var fd = new window.FormData();
                angular.forEach(data, function(value, key) {
                    console.log(value);
                    fd.append(key, value);
                });
                return {
                    data: fd,
                    opts: {
                        transformRequest: angular.identity,
                        headers: {
                            'Content-Type': undefined
                        }
                    }
                };
            }
        }]);
        .directive('jfilestyle', function(){
            return {
                restrict: 'A',
                scope: {
                    options: '=jfilestyle'
                },
                controller: ['$scope', function($scope){ /* vacio, para tirar error */ }],
                link: function(scope, element, attrs/*, controller(s)*/) {
                    angular.element(element).jfilestyle(scope.options);
                }
            }
        })
        .directive('fileModel', ['$parse', function ($parse) {
            return {
                restrict: 'A',
                require: 'jfilestyle',
                link: function(scope, element, attrs) {
                    var model = $parse(attrs.fileModel);
                    var modelSetter = model.assign;

                    scope.$watch(attrs.fileModel, function(value){
                        if (!value) {
                            element.jfilestyle('clear');
                        }
                    });
                    element.bind('change', function(){
                        scope.$apply(function(){
                            modelSetter(scope, element[0].files[0]);
                        });
                    });
                }
            };
        }]);
})();