Angular JS Shortcut Directive

controller.js

/** ... **/

$scope.save = function(){

}

$scope.delete = function(){

}

/** ... **/

shortcut.js

'use strict';
/* global jQuery */
/**
 * @ngdoc directivew
 * @name directive:shortcut
 * @description Directive for creating key shortcuts
 * # shortcut
 */
angular.module('App')
    .directive('shortcut', function() {
        return {
            name: 'shortcut',
            restrict: 'A',
            scope: true,
            replace: true,
            link: function($scope, $el, attrs) {

                /*exported options */
                var shortcuts;
                try {
                    shortcuts = JSON.parse(attrs.shortcut.replace(/'/g, '"'));
                } catch (e) {
                    throw new Error('Invalid JSON for shortcut');
                }

                var options = [];
                Object.keys(shortcuts).forEach(function(key) {
                    var keys = key.split('+');
                    var shiftIndex = keys.indexOf('shift');
                    var useShift = shiftIndex !== -1;
                    if (useShift) {
                        keys.splice(shiftIndex, 1);
                    }

                    var ctrlIndex = keys.indexOf('ctrl');
                    var useCtrl = ctrlIndex !== -1;
                    if (useCtrl) {
                        keys.splice(ctrlIndex, 1);
                    }

                    var altIndex = keys.indexOf('alt');
                    var useAlt = altIndex !== -1;
                    if (useAlt) {
                        keys.splice(altIndex, 1);
                    }

                    var opts = typeof(shortcuts[key]) === 'string' ? {
                        callback: shortcuts[key],
                        preventDefault: false
                    } : shortcuts[key];

                    if (!opts.callback) {
                        throw new Error('Shortuct needs a callback');
                    }

                    options.push({
                        shiftKey: useShift,
                        ctrlKey: useCtrl,
                        altKey: useAlt,
                        keys: keys,
                        callback: opts.callback,
                        preventDefault: opts.preventDefault
                    });
                });


                var elSelector = attrs.el || document;

                jQuery(elSelector).on('keypress', function(e) {
                    /* global options */
                    options.forEach(function(option) {

                        if (option.shiftKey && !e.shiftKey || option.altKey && !e.altKey || option.ctrlKey && !e.ctrlKey) {
                            return false;
                        }

                        var keyPressed = option.keys.indexOf(String.fromCharCode(e.which)) !== -1;

                        if (keyPressed) {

                            console.log(option, e.shiftKey, e.altKey, e.ctrlKey, 'key pressed', String.fromCharCode(e.which));
                            $scope.$apply($scope[option.callback]);

                            if (option.preventDefault) {
                                e.preventDefault();
                                return false;
                            }
                        }
                    });
                });
            }
        };
    });

view.html

<div shortcut="{'shift+S' : 'save', 'shift+W' : 'delete'}"></div>