private async void CountDetectedFaces()

in FamilyNotes/UserDetection/UserPresence.cs [367:431]
47 lines of code
12 McCabe index (conditional complexity)

        private async void CountDetectedFaces(IReadOnlyList<DetectedFace> faces)
        {
            FaceCount = $"{_detectionString} {faces.Count.ToString()}";

            // If we detect any faces, kill our no faces timer
            if (faces.Count != 0)
            {
                if (_noFacesTimer != null)
                {
                    _noFacesTimer.Dispose();
                }
            }
            // Otherwise, if we are filtering and don't have a timer
            else if (_currentlyFiltered && (_noFacesTimer == null))
            {
                // Create a callback
                TimerCallback noFacesCallback = (object stateInfo) =>
                {
                    _dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => 
                    {
                        OnFilterOnFace(_unfilteredName);
                        _noFacesTimer = null;
                    });
                    _noFacesTimer.Dispose();
                };

                // Set our timer
                _noFacesTimer = new Timer(noFacesCallback, null, NoFacesTime, Timeout.Infinite);
            }

            // We are also going to take an image the first time that we detect exactly one face.
            // Sidenote - to avoid a race-condition, I had to use a boolean. Just checking for _faceCaptureStill == null could produce an error.
            if ((faces.Count == 1) && !_holdForTimer && !_currentlyFiltered)
            {
                // Kick off the timer so we don't keep taking pictures, but will resubmit if we are not filtered
                _holdForTimer = true;
                
                // Take the picture
                _faceCaptureStill = await ApplicationData.Current.LocalFolder.CreateFileAsync("FaceDetected.jpg", CreationCollisionOption.ReplaceExisting);
                await _mediaCapture.CapturePhotoToStorageFileAsync(ImageEncodingProperties.CreateJpeg(), _faceCaptureStill);


                if (((App)Application.Current).AppSettings.FaceApiKey != "" && FacialSimilarity.InitialTrainingPerformed)
                {
                    var UserName = await FacialSimilarity.CheckForUserAsync(new Uri("ms-appdata:///local/FaceDetected.jpg"));
                    if (UserName != "")
                    {
                        OnFilterOnFace(UserName);
                    }
                }

                // Allow the camera to take another picture in 10 seconds
                TimerCallback callback = (Object stateInfo) => 
                    {
                        // Now that the timer is expired, we no longer need to hold
                        // Nothing else to do since the timer will be restarted when the picture is taken
                        _holdForTimer = false;
                        if (_pictureTimer != null)
                        {
                            _pictureTimer.Dispose();
                        }
                    };
                _pictureTimer = new Timer(callback, null, 10000, Timeout.Infinite);
            }
        }