public static async Task TrainDetectionAsync()

in FamilyNotes/UserDetection/FacialSimilarity.cs [64:155]
73 lines of code
8 McCabe index (conditional complexity)

        public static async Task<int> TrainDetectionAsync()
        {
            StorageFolder LocalFolder = ApplicationData.Current.LocalFolder;
            await _semaphore.WaitAsync();

            await LoadSettingsAsync();
            await CheckTransactionCapAsync();
            _userImages.Clear();
            _userFacialIDs.Clear();
            _userNames.Clear();
            int FacesAdded = 0;

            // Find Users directory and load each folder of user images
            try
            {
                StorageFolder Users = await LocalFolder.GetFolderAsync("Users");
                IReadOnlyList<StorageFolder> UserDirectories = await Users.GetFoldersAsync();
                foreach(StorageFolder UserFolder in UserDirectories)
                {
                    string UserName = UserFolder.Name;
                    IReadOnlyList<StorageFile> UserPictures = await UserFolder.GetFilesAsync();

                    //Just retrieve the first image for each user, assuming the user has an image. 
                    if (UserPictures.Any<StorageFile>())
                    {
                        _userImages.Add(UserName, UserPictures.First<StorageFile>());
                    }
                }
            }
            catch (System.IO.FileNotFoundException)
            {
                _semaphore.Release();
                return FacesAdded;
            }

            // Delete any existing FaceList held by the Azure Face service. Exception is thrown and surpressed if specified list didn't exist.
            try
            {
                await WaitOnTransactionCapAsync();
                await _faceClient.FaceList.DeleteAsync(_listKey);
                _transactionCount++;
            }
            catch (Exception)
            {
            }

            // Create a new FaceList in the Azure Face service for persistent Face storage.
            try
            {
                await WaitOnTransactionCapAsync();
                await _faceClient.FaceList.CreateAsync(_listKey, _listKey, "");
                _transactionCount++;
            }
            catch (Exception)
            {
                _semaphore.Release();
                return FacesAdded;
            }


            var UserNames = _userImages.Keys;

            foreach(var UserName in UserNames)
            {
                var UserImageStorageFile = _userImages[UserName];

                using(var UserImageFilestream = File.OpenRead(UserImageStorageFile.Path))
                {
                    try
                    {
                        // Adds face to list and gets persistent face ID.
                        await WaitOnTransactionCapAsync();
                        var DetectedFaceID = await _faceClient.FaceList.AddFaceFromStreamAsync(_listKey, UserImageFilestream, UserName);
                        _transactionCount++;
                        _userFacialIDs.Add(UserName, DetectedFaceID.PersistedFaceId);
                        _userNames.Add(DetectedFaceID.PersistedFaceId, UserName);
                        FacesAdded++;
                    }
                    catch(Exception)
                    {
                        // This exception occurs when the Azure Face service AddFaceToListAsync call isn't able to detect a singlular face 
                        // in the profile picture. Additional logic could be added to better determine the cause of failure and surface that to
                        // the app for retry.
                    }

                }
            }

            InitialTrainingPerformed = true;
            _semaphore.Release();
            return FacesAdded;
        }