disable "attended" button if the person is not registered

angular_app/js/controllers.js

@@ -228,7 +228,7 @@ eventManControllers.controller('PersonDetailsCtrl', ['$scope', '$stateParams', '
                 var data = angular.copy(person);
                 data._id = evnt._id;
                 data.person_id = person._id;
-                data.attended = true;
+                data.attended = false;
                 Event.addAttendee(data,
                     function(data) {
                         $scope.events = Person.getEvents({_id: $stateParams.id, all: true});

angular_app/person-info.html

@@ -39,7 +39,7 @@
                             <button class="btn btn-link" name="switch-registered" ng-click="switchRegistered(event, person, !event.person_data.person_id)"><span class="glyphicon {{(event.person_data.person_id) && 'glyphicon-ok-sign text-success' || 'glyphicon-remove-sign text-danger'}}"></span></button>
                         </td>
                         <td>
-                            <button class="btn btn-link" name="switch-attended" ng-click="updateAttendee(event, !event.person_data.attended)"><span class="glyphicon {{(event.person_data.attended) && 'glyphicon-ok-sign text-success' || 'glyphicon-remove-sign text-danger'}}"></span></button>
+                            <button ng-disabled="!event.person_data.person_id" class="btn btn-link" name="switch-attended" ng-click="updateAttendee(event, !event.person_data.attended)"><span class="glyphicon {{(event.person_data.attended) && 'glyphicon-ok-sign text-success' || 'glyphicon-remove-sign text-danger'}}"></span></button>
                         </td>
                     </tr>
                 </tbody>