update dependencies

Update Libation to work with new AAXClean.Codecs

AaxDecrypter/AaxDecrypter.csproj

@@ -1,12 +1,16 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="AAXClean" Version="0.1.9" />
-    <PackageReference Include="Dinah.Core" Version="1.1.1.2" />
+    <PackageReference Include="AAXClean" Version="0.3.2" />
+    <PackageReference Include="AAXClean.Codecs" Version="0.1.10" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\FileManager\FileManager.csproj" />
   </ItemGroup>
 
 </Project>

AaxDecrypter/AaxcDownloadConvertBase.cs

@@ -0,0 +1,95 @@
+using System;
+using AAXClean;
+using Dinah.Core.Net.Http;
+
+namespace AaxDecrypter
+{
+	public abstract class AaxcDownloadConvertBase : AudiobookDownloadBase
+	{
+		public event EventHandler<AppleTags> RetrievedMetadata;
+
+		protected OutputFormat OutputFormat { get; }
+
+		protected AaxFile AaxFile;
+
+		protected AaxcDownloadConvertBase(string outFileName, string cacheDirectory, DownloadLicense dlLic, OutputFormat outputFormat)
+			: base(outFileName, cacheDirectory, dlLic)
+		{
+			OutputFormat = outputFormat;
+		}
+
+		/// <summary>Setting cover art by this method will insert the art into the audiobook metadata</summary>
+		public override void SetCoverArt(byte[] coverArt)
+		{
+			base.SetCoverArt(coverArt);
+			if (coverArt is not null && AaxFile?.AppleTags is not null)
+				AaxFile.AppleTags.Cover = coverArt;
+		}
+
+		protected bool Step_GetMetadata()
+		{
+			AaxFile = new AaxFile(InputFileStream);
+
+			OnRetrievedTitle(AaxFile.AppleTags.TitleSansUnabridged);
+			OnRetrievedAuthors(AaxFile.AppleTags.FirstAuthor ?? "[unknown]");
+			OnRetrievedNarrators(AaxFile.AppleTags.Narrator ?? "[unknown]");
+			OnRetrievedCoverArt(AaxFile.AppleTags.Cover);
+
+			RetrievedMetadata?.Invoke(this, AaxFile.AppleTags);
+
+			return !IsCanceled;
+		}
+
+		protected DownloadProgress Step_DownloadAudiobook_Start()
+		{
+			var zeroProgress = new DownloadProgress
+			{
+				BytesReceived = 0,
+				ProgressPercentage = 0,
+				TotalBytesToReceive = InputFileStream.Length
+			};
+
+			OnDecryptProgressUpdate(zeroProgress);
+
+			AaxFile.SetDecryptionKey(DownloadLicense.AudibleKey, DownloadLicense.AudibleIV);
+			return zeroProgress;
+		}
+
+		protected void Step_DownloadAudiobook_End(DownloadProgress zeroProgress)
+		{
+			AaxFile.Close();
+
+			CloseInputFileStream();
+
+			OnDecryptProgressUpdate(zeroProgress);
+		}
+
+		protected void AaxFile_ConversionProgressUpdate(object sender, ConversionProgressEventArgs e)
+		{
+			var duration = AaxFile.Duration;
+			var remainingSecsToProcess = (duration - e.ProcessPosition).TotalSeconds;
+			var estTimeRemaining = remainingSecsToProcess / e.ProcessSpeed;
+
+			if (double.IsNormal(estTimeRemaining))
+				OnDecryptTimeRemaining(TimeSpan.FromSeconds(estTimeRemaining));
+
+			var progressPercent = e.ProcessPosition.TotalSeconds / duration.TotalSeconds;
+
+			OnDecryptProgressUpdate(
+				new DownloadProgress
+				{
+					ProgressPercentage = 100 * progressPercent,
+					BytesReceived = (long)(InputFileStream.Length * progressPercent),
+					TotalBytesToReceive = InputFileStream.Length
+				});
+		}
+
+		public override void Cancel()
+		{
+			IsCanceled = true;
+			AaxFile?.Cancel();
+			AaxFile?.Dispose();
+			CloseInputFileStream();
+		}
+	}
+}

AaxDecrypter/AaxcDownloadConverter.cs

@@ -1,225 +0,0 @@
-using AAXClean;
-using Dinah.Core;
-using Dinah.Core.IO;
-using Dinah.Core.Net.Http;
-using Dinah.Core.StepRunner;
-using System;
-using System.IO;
-using System.Linq;
-
-namespace AaxDecrypter
-{
-    public class AaxcDownloadConverter : AudiobookDownloadBase
-    {
-        const int MAX_FILENAME_LENGTH = 255;
-        private static readonly TimeSpan minChapterLength = TimeSpan.FromSeconds(3);
-        protected override StepSequence steps { get; }
-
-        private AaxFile aaxFile;
-        private OutputFormat OutputFormat { get; }
-
-        public AaxcDownloadConverter(string outFileName, string cacheDirectory, DownloadLicense dlLic, OutputFormat outputFormat, bool splitFileByChapters)
-            :base(outFileName, cacheDirectory, dlLic)
-        {
-            OutputFormat = outputFormat;
-
-            steps = new StepSequence
-            {
-                Name = "Download and Convert Aaxc To " + OutputFormat,
-
-                ["Step 1: Get Aaxc Metadata"] = Step1_GetMetadata,
-                ["Step 2: Download Decrypted Audiobook"] = splitFileByChapters
-                    ? Step2_DownloadAudiobookAsMultipleFilesPerChapter
-                    : Step2_DownloadAudiobookAsSingleFile,
-                ["Step 3: Create Cue"] = splitFileByChapters 
-                    ? () => true 
-                    : Step3_CreateCue,
-                ["Step 4: Cleanup"] = Step4_Cleanup,
-            };
-        }
-
-        /// <summary>
-        /// Setting cover art by this method will insert the art into the audiobook metadata
-        /// </summary>
-        public override void SetCoverArt(byte[] coverArt)
-        {
-            base.SetCoverArt(coverArt);
-
-            aaxFile?.AppleTags.SetCoverArt(coverArt);
-        }
-
-        protected override bool Step1_GetMetadata()
-        {    
-            aaxFile = new AaxFile(InputFileStream);
-
-            OnRetrievedTitle(aaxFile.AppleTags.TitleSansUnabridged);
-            OnRetrievedAuthors(aaxFile.AppleTags.FirstAuthor ?? "[unknown]");
-            OnRetrievedNarrators(aaxFile.AppleTags.Narrator ?? "[unknown]");
-            OnRetrievedCoverArt(aaxFile.AppleTags.Cover);
-
-            return !isCanceled;
-        }
-
-        protected override bool Step2_DownloadAudiobookAsSingleFile()
-        {
-            var zeroProgress = Step2_Start();
-            
-            if (File.Exists(outputFileName))
-                FileExt.SafeDelete(outputFileName);
-
-            var outputFile =  File.Open(outputFileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
-
-            aaxFile.ConversionProgressUpdate += AaxFile_ConversionProgressUpdate;
-            var decryptionResult = OutputFormat == OutputFormat.M4b ? aaxFile.ConvertToMp4a(outputFile, downloadLicense.ChapterInfo) : aaxFile.ConvertToMp3(outputFile);
-            aaxFile.ConversionProgressUpdate -= AaxFile_ConversionProgressUpdate;
-
-            downloadLicense.ChapterInfo = aaxFile.Chapters;
-            
-            Step2_End(zeroProgress);
-
-            return decryptionResult == ConversionResult.NoErrorsDetected && !isCanceled;
-        }
-
-        private bool Step2_DownloadAudiobookAsMultipleFilesPerChapter()
-        {
-            var zeroProgress = Step2_Start();
-
-            var chapters = downloadLicense.ChapterInfo.Chapters.ToList();
-
-            //Ensure split files are at least minChapterLength in duration.
-            var splitChapters = new ChapterInfo();
-
-            var runningTotal = TimeSpan.Zero;
-            string title = "";
-
-            for (int i = 0; i < chapters.Count; i++)
-            {
-                if (runningTotal == TimeSpan.Zero)
-                    title = chapters[i].Title;
-
-                runningTotal += chapters[i].Duration;
-
-                if (runningTotal >= minChapterLength)
-                {
-                    splitChapters.AddChapter(title, runningTotal);
-                    runningTotal = TimeSpan.Zero;
-                }
-            }
-
-            aaxFile.ConversionProgressUpdate += AaxFile_ConversionProgressUpdate;
-            if(OutputFormat == OutputFormat.M4b) 
-                ConvertToMultiMp4b(splitChapters);
-            else 
-                ConvertToMultiMp3(splitChapters);
-            aaxFile.ConversionProgressUpdate -= AaxFile_ConversionProgressUpdate;
-
-            Step2_End(zeroProgress);
-
-            return !isCanceled;
-        }
-
-        private DownloadProgress Step2_Start()
-        {
-            var zeroProgress = new DownloadProgress
-            {
-                BytesReceived = 0,
-                ProgressPercentage = 0,
-                TotalBytesToReceive = InputFileStream.Length
-            };
-
-            OnDecryptProgressUpdate(zeroProgress);
-
-            aaxFile.SetDecryptionKey(downloadLicense.AudibleKey, downloadLicense.AudibleIV);
-            return zeroProgress;
-        }
-        
-        private void Step2_End(DownloadProgress zeroProgress)
-        {
-            aaxFile.Close();
-
-            CloseInputFileStream();
-
-            OnDecryptProgressUpdate(zeroProgress);
-        }
-
-        private void ConvertToMultiMp4b(ChapterInfo splitChapters)
-        {
-            var chapterCount = 0;
-            aaxFile.ConvertToMultiMp4a(splitChapters, newSplitCallback =>
-            {
-                var fileName = GetMultipartFileName(outputFileName, ++chapterCount, newSplitCallback.Chapter.Title);
-                if (File.Exists(fileName))
-                    FileExt.SafeDelete(fileName);
-                newSplitCallback.OutputFile = File.Open(fileName, FileMode.OpenOrCreate);
-            });
-        }
-        
-        private void ConvertToMultiMp3(ChapterInfo splitChapters)
-        {
-            var chapterCount = 0;
-            aaxFile.ConvertToMultiMp3(splitChapters, newSplitCallback =>
-            {
-                var fileName = GetMultipartFileName(outputFileName, ++chapterCount, newSplitCallback.Chapter.Title);
-                if (File.Exists(fileName))
-                    FileExt.SafeDelete(fileName);
-                newSplitCallback.OutputFile = File.Open(fileName, FileMode.OpenOrCreate);
-                newSplitCallback.LameConfig.ID3.Track = chapterCount.ToString();
-            });
-        }
-
-        private static string GetMultipartFileName(string baseFileName, int chapterCount, string chapterTitle)
-        {
-            string extension = Path.GetExtension(baseFileName);
-
-            var fileNameChars = $"{Path.GetFileNameWithoutExtension(baseFileName)} - {chapterCount:D2} - {chapterTitle}".ToCharArray();
-
-            //Replace illegal path characters with spaces.
-            for (int i = 0; i <fileNameChars.Length; i++)
-			{
-                foreach (var illegal in Path.GetInvalidFileNameChars())
-				{
-                    if (fileNameChars[i] == illegal)
-					{
-                        fileNameChars[i] = ' ';
-                        break;
-					}
-				}
-			}
-
-            var fileName = new string(fileNameChars).Truncate(MAX_FILENAME_LENGTH - extension.Length);
-
-            return Path.Combine(Path.GetDirectoryName(baseFileName), fileName + extension);
-		}
-
-        private void AaxFile_ConversionProgressUpdate(object sender, ConversionProgressEventArgs e)
-        {
-            var duration = aaxFile.Duration;
-            double remainingSecsToProcess = (duration - e.ProcessPosition).TotalSeconds;
-            double estTimeRemaining = remainingSecsToProcess / e.ProcessSpeed;
-
-            if (double.IsNormal(estTimeRemaining))
-                OnDecryptTimeRemaining(TimeSpan.FromSeconds(estTimeRemaining));
-
-            double progressPercent = e.ProcessPosition.TotalSeconds / duration.TotalSeconds;
-
-            OnDecryptProgressUpdate(
-                new DownloadProgress
-                {
-                    ProgressPercentage = 100 * progressPercent,
-                    BytesReceived = (long)(InputFileStream.Length * progressPercent),
-                    TotalBytesToReceive = InputFileStream.Length
-                });
-        }
-
-        public override void Cancel()
-        {
-            isCanceled = true;
-            aaxFile?.Cancel();
-            aaxFile?.Dispose();
-            CloseInputFileStream();
-        }
-
-		protected override int GetSpeedup(TimeSpan elapsed)
-            => (int)(aaxFile.Duration.TotalSeconds / (long)elapsed.TotalSeconds);
-	}
-}

AaxDecrypter/AaxcDownloadMultiConverter.cs

@@ -0,0 +1,143 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using AAXClean;
+using AAXClean.Codecs;
+using Dinah.Core.StepRunner;
+using FileManager;
+
+namespace AaxDecrypter
+{
+	public class AaxcDownloadMultiConverter : AaxcDownloadConvertBase
+	{
+		protected override StepSequence Steps { get; }
+
+        private Func<MultiConvertFileProperties, string> multipartFileNameCallback { get; }
+
+        private static TimeSpan minChapterLength { get; } = TimeSpan.FromSeconds(3);
+		private List<string> multiPartFilePaths { get; } = new List<string>();
+
+        public AaxcDownloadMultiConverter(string outFileName, string cacheDirectory, DownloadLicense dlLic, OutputFormat outputFormat,
+            Func<MultiConvertFileProperties, string> multipartFileNameCallback = null)
+			: base(outFileName, cacheDirectory, dlLic, outputFormat)
+        {
+            Steps = new StepSequence
+            {
+                Name = "Download and Convert Aaxc To " + OutputFormat,
+
+                ["Step 1: Get Aaxc Metadata"] = Step_GetMetadata,
+                ["Step 2: Download Decrypted Audiobook"] = Step_DownloadAudiobookAsMultipleFilesPerChapter,
+                ["Step 3: Cleanup"] = Step_Cleanup,
+            };
+            this.multipartFileNameCallback = multipartFileNameCallback ?? MultiConvertFileProperties.DefaultMultipartFilename;
+        }
+
+        /*
+https://github.com/rmcrackan/Libation/pull/127#issuecomment-939088489
+
+If the chapter truly is empty, that is, 0 audio frames in length, then yes it is ignored.
+If the chapter is shorter than 3 seconds long but still has some audio frames, those frames are combined with the following chapter and not split into a new file.
+
+I also implemented file naming by chapter title. When 2 or more consecutive chapters are combined, the first of the combined chapter's title is used in the file name. For example, given an audiobook with the following chapters:
+
+00:00:00 - 00:00:02 | Part 1
+00:00:02 - 00:35:00 | Chapter 1
+00:35:02 - 01:02:00 | Chapter 2
+01:02:00 - 01:02:02 | Part 2
+01:02:02 - 01:41:00 | Chapter 3
+01:41:00 - 02:05:00 | Chapter 4
+
+The book will be split into the following files:
+
+00:00:00 - 00:35:00 | Book - 01 - Part 1.m4b
+00:35:00 - 01:02:00 | Book - 02 - Chapter 2.m4b
+01:02:00 - 01:41:00 | Book - 03 - Part 2.m4b
+01:41:00 - 02:05:00 | Book - 04 - Chapter 4.m4b
+
+That naming may not be desirable for everyone, but it's an easy change to instead use the last of the combined chapter's title in the file name.
+         */
+        private bool Step_DownloadAudiobookAsMultipleFilesPerChapter()
+        {
+            var zeroProgress = Step_DownloadAudiobook_Start();
+
+            var chapters = DownloadLicense.ChapterInfo.Chapters.ToList();
+
+            // Ensure split files are at least minChapterLength in duration.
+            var splitChapters = new ChapterInfo();
+
+            var runningTotal = TimeSpan.Zero;
+            string title = "";
+
+            for (int i = 0; i < chapters.Count; i++)
+            {
+                if (runningTotal == TimeSpan.Zero)
+                    title = chapters[i].Title;
+
+                runningTotal += chapters[i].Duration;
+
+                if (runningTotal >= minChapterLength)
+                {
+                    splitChapters.AddChapter(title, runningTotal);
+                    runningTotal = TimeSpan.Zero;
+                }
+            }
+
+            // reset, just in case
+            multiPartFilePaths.Clear();
+
+            AaxFile.ConversionProgressUpdate += AaxFile_ConversionProgressUpdate;
+            if (OutputFormat == OutputFormat.M4b)
+                ConvertToMultiMp4a(splitChapters);
+            else
+                ConvertToMultiMp3(splitChapters);
+            AaxFile.ConversionProgressUpdate -= AaxFile_ConversionProgressUpdate;
+
+            Step_DownloadAudiobook_End(zeroProgress);
+
+            var success = !IsCanceled;
+
+            if (success)
+                foreach (var path in multiPartFilePaths)
+                    OnFileCreated(path);
+
+            return success;
+        }
+
+        private void ConvertToMultiMp4a(ChapterInfo splitChapters)
+        {
+            var chapterCount = 0;
+            AaxFile.ConvertToMultiMp4a(splitChapters, newSplitCallback =>
+                createOutputFileStream(++chapterCount, splitChapters, newSplitCallback)
+            );
+        }
+
+        private void ConvertToMultiMp3(ChapterInfo splitChapters)
+        {
+            var chapterCount = 0;
+            AaxFile.ConvertToMultiMp3(splitChapters, newSplitCallback =>
+            {
+                createOutputFileStream(++chapterCount, splitChapters, newSplitCallback);
+                ((NAudio.Lame.LameConfig)newSplitCallback.UserState).ID3.Track = chapterCount.ToString();
+            });
+        }
+
+        private void createOutputFileStream(int currentChapter, ChapterInfo splitChapters, NewSplitCallback newSplitCallback)
+        {
+            var fileName = multipartFileNameCallback(new()
+            {
+                OutputFileName = OutputFileName,
+                PartsPosition = currentChapter,
+                PartsTotal = splitChapters.Count,
+                Title = newSplitCallback?.Chapter?.Title
+            });
+            fileName = FileUtility.GetValidFilename(fileName);
+
+            multiPartFilePaths.Add(fileName);
+
+            FileUtility.SaferDelete(fileName);
+
+            newSplitCallback.OutputFile = File.Open(fileName, FileMode.OpenOrCreate);
+        }
+    }
+}

AaxDecrypter/AaxcDownloadSingleConverter.cs

@@ -0,0 +1,54 @@
+using System;
+using System.IO;
+using AAXClean;
+using AAXClean.Codecs;
+using Dinah.Core.StepRunner;
+using FileManager;
+
+namespace AaxDecrypter
+{
+	public class AaxcDownloadSingleConverter : AaxcDownloadConvertBase
+	{
+		protected override StepSequence Steps { get; }
+
+        public AaxcDownloadSingleConverter(string outFileName, string cacheDirectory, DownloadLicense dlLic, OutputFormat outputFormat)
+			: base(outFileName, cacheDirectory, dlLic, outputFormat)
+        {
+            Steps = new StepSequence
+            {
+                Name = "Download and Convert Aaxc To " + OutputFormat,
+
+                ["Step 1: Get Aaxc Metadata"] = Step_GetMetadata,
+                ["Step 2: Download Decrypted Audiobook"] = Step_DownloadAudiobookAsSingleFile,
+                ["Step 3: Create Cue"] = Step_CreateCue,
+                ["Step 4: Cleanup"] = Step_Cleanup,
+            };
+        }
+
+        private bool Step_DownloadAudiobookAsSingleFile()
+        {
+            var zeroProgress = Step_DownloadAudiobook_Start();
+
+            FileUtility.SaferDelete(OutputFileName);
+
+            var outputFile = File.Open(OutputFileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
+
+            AaxFile.ConversionProgressUpdate += AaxFile_ConversionProgressUpdate;
+            var decryptionResult
+                = OutputFormat == OutputFormat.M4b
+                ? AaxFile.ConvertToMp4a(outputFile, DownloadLicense.ChapterInfo)
+                : AaxFile.ConvertToMp3(outputFile);
+            AaxFile.ConversionProgressUpdate -= AaxFile_ConversionProgressUpdate;
+
+            DownloadLicense.ChapterInfo = AaxFile.Chapters;
+
+            Step_DownloadAudiobook_End(zeroProgress);
+
+            var success = decryptionResult == ConversionResult.NoErrorsDetected && !IsCanceled;
+            if (success)
+                base.OnFileCreated(OutputFileName);
+
+            return success;
+        }
+    }
+}

AaxDecrypter/AudiobookDownloadBase.cs

@@ -1,13 +1,9 @@
-using Dinah.Core;
-using Dinah.Core.IO;
+using System;
+using System.IO;
+using Dinah.Core;
 using Dinah.Core.Net.Http;
 using Dinah.Core.StepRunner;
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
+using FileManager;
 
 namespace AaxDecrypter
 {
@@ -21,81 +17,74 @@ namespace AaxDecrypter
 		public event EventHandler<byte[]> RetrievedCoverArt;
 		public event EventHandler<DownloadProgress> DecryptProgressUpdate;
 		public event EventHandler<TimeSpan> DecryptTimeRemaining;
+		public event EventHandler<string> FileCreated;
 
-		public string AppName { get; set; }
-
-		protected bool isCanceled { get; set; }
-		protected string outputFileName { get; }
-		protected string cacheDir { get; }
-		protected DownloadLicense downloadLicense { get; }
+		protected bool IsCanceled { get; set; }
+		protected string OutputFileName { get; private set; }
+		protected DownloadLicense DownloadLicense { get; }
 		protected NetworkFileStream InputFileStream => (nfsPersister ??= OpenNetworkFileStream()).NetworkFileStream;
 
+		// Don't give the property a 'set'. This should have to be an obvious choice; not accidental
+		protected void SetOutputFileName(string newOutputFileName) => OutputFileName = newOutputFileName;
 
-		protected abstract StepSequence steps { get; }
+		protected abstract StepSequence Steps { get; }
 		private NetworkFileStreamPersister nfsPersister;
 
-		private string jsonDownloadState => Path.Combine(cacheDir, Path.GetFileNameWithoutExtension(outputFileName) + ".json");
-		private string tempFile => PathLib.ReplaceExtension(jsonDownloadState, ".tmp");
+		private string jsonDownloadState { get; }
+		private string tempFile => Path.ChangeExtension(jsonDownloadState, ".tmp");
 
-		public AudiobookDownloadBase(string outFileName, string cacheDirectory, DownloadLicense dlLic)
+		protected AudiobookDownloadBase(string outFileName, string cacheDirectory, DownloadLicense dlLic)
 		{
-			AppName = GetType().Name;
+			OutputFileName = ArgumentValidator.EnsureNotNullOrWhiteSpace(outFileName, nameof(outFileName));
 
-			ArgumentValidator.EnsureNotNullOrWhiteSpace(outFileName, nameof(outFileName));
-			outputFileName = outFileName;
-
-			var outDir = Path.GetDirectoryName(outputFileName);
+			var outDir = Path.GetDirectoryName(OutputFileName);
 			if (!Directory.Exists(outDir))
-				throw new ArgumentNullException(nameof(outDir), "Directory does not exist");
-			if (File.Exists(outputFileName))
-				File.Delete(outputFileName);
+				throw new DirectoryNotFoundException($"Directory does not exist: {nameof(outDir)}");
 
 			if (!Directory.Exists(cacheDirectory))
-				throw new ArgumentNullException(nameof(cacheDirectory), "Directory does not exist");
-			cacheDir = cacheDirectory;
+				throw new DirectoryNotFoundException($"Directory does not exist: {nameof(cacheDirectory)}");
+			jsonDownloadState = Path.Combine(cacheDirectory, Path.ChangeExtension(OutputFileName, ".json"));
 
-			downloadLicense = ArgumentValidator.EnsureNotNull(dlLic, nameof(dlLic));
+			DownloadLicense = ArgumentValidator.EnsureNotNull(dlLic, nameof(dlLic));
+
+			// delete file after validation is complete
+			FileUtility.SaferDelete(OutputFileName);
 		}
 
 		public abstract void Cancel();
-		protected abstract int GetSpeedup(TimeSpan elapsed);
-		protected abstract bool Step2_DownloadAudiobookAsSingleFile();
-		protected abstract bool Step1_GetMetadata();
 
 		public virtual void SetCoverArt(byte[] coverArt)
 		{
-			if (coverArt is null) return;
-
-			OnRetrievedCoverArt(coverArt);
+			if (coverArt is not null)
+				OnRetrievedCoverArt(coverArt);
 		}
 
-
 		public bool Run()
 		{
-			var (IsSuccess, Elapsed) = steps.Run();
+			var (IsSuccess, Elapsed) = Steps.Run();
 
 			if (!IsSuccess)
-			{
-				Console.WriteLine("WARNING-Conversion failed");
-				return false;
-			}
+				Serilog.Log.Logger.Error("Conversion failed");
 
-			//Serilog.Log.Logger.Information($"Speedup is {GetSpeedup(Elapsed)}x realtime.");
-			return true;
-		}		
+			return IsSuccess;
+		}
 
-		protected void OnRetrievedTitle(string title) 
+		protected void OnRetrievedTitle(string title)
 			=> RetrievedTitle?.Invoke(this, title);
-		protected void OnRetrievedAuthors(string authors) 
+		protected void OnRetrievedAuthors(string authors)
 			=> RetrievedAuthors?.Invoke(this, authors);
-		protected void OnRetrievedNarrators(string narrators) 
+		protected void OnRetrievedNarrators(string narrators)
 			=> RetrievedNarrators?.Invoke(this, narrators);
-		protected void OnRetrievedCoverArt(byte[] coverArt) 
+
+		protected void OnRetrievedCoverArt(byte[] coverArt)
 			=> RetrievedCoverArt?.Invoke(this, coverArt);
+
 		protected void OnDecryptProgressUpdate(DownloadProgress downloadProgress) 
 			=> DecryptProgressUpdate?.Invoke(this, downloadProgress);
-		protected void OnDecryptTimeRemaining(TimeSpan timeRemaining) 
+		protected void OnDecryptTimeRemaining(TimeSpan timeRemaining)
 			=> DecryptTimeRemaining?.Invoke(this, timeRemaining);
+		protected void OnFileCreated(string path)
+			=> FileCreated?.Invoke(this, path);
 
 		protected void CloseInputFileStream()
 		{
@@ -103,62 +92,59 @@ namespace AaxDecrypter
 			nfsPersister?.Dispose();
 		}
 
-		protected bool Step3_CreateCue()
+		protected bool Step_CreateCue()
 		{
 			// not a critical step. its failure should not prevent future steps from running
 			try
 			{
-				File.WriteAllText(PathLib.ReplaceExtension(outputFileName, ".cue"), Cue.CreateContents(Path.GetFileName(outputFileName), downloadLicense.ChapterInfo));
+				var path = Path.ChangeExtension(OutputFileName, ".cue");
+				path = FileUtility.GetValidFilename(path);
+				File.WriteAllText(path, Cue.CreateContents(Path.GetFileName(OutputFileName), DownloadLicense.ChapterInfo));
+				OnFileCreated(path);
 			}
 			catch (Exception ex)
 			{
-				Serilog.Log.Logger.Error(ex, $"{nameof(Step3_CreateCue)}. FAILED");
+				Serilog.Log.Logger.Error(ex, $"{nameof(Step_CreateCue)}. FAILED");
 			}
-			return !isCanceled;
+			return !IsCanceled;
 		}
 
-		protected bool Step4_Cleanup()
+		protected bool Step_Cleanup()
 		{
-			FileExt.SafeDelete(jsonDownloadState);
-			FileExt.SafeDelete(tempFile);
-			return !isCanceled;
+			FileUtility.SaferDelete(jsonDownloadState);
+			FileUtility.SaferDelete(tempFile);
+			return !IsCanceled;
 		}
 
 		private NetworkFileStreamPersister OpenNetworkFileStream()
 		{
-			NetworkFileStreamPersister nfsp;
+			if (!File.Exists(jsonDownloadState))
+				return NewNetworkFilePersister();
 
-			if (File.Exists(jsonDownloadState))
+			try
 			{
-				try
-				{
-					nfsp = new NetworkFileStreamPersister(jsonDownloadState);
-					//If More than ~1 hour has elapsed since getting the download url, it will expire.
-					//The new url will be to the same file.
-					nfsp.NetworkFileStream.SetUriForSameFile(new Uri(downloadLicense.DownloadUrl));
-				}
-				catch
-				{
-					FileExt.SafeDelete(jsonDownloadState);
-					FileExt.SafeDelete(tempFile);
-					nfsp = NewNetworkFilePersister();
-				}
+				var nfsp = new NetworkFileStreamPersister(jsonDownloadState);
+				// If More than ~1 hour has elapsed since getting the download url, it will expire.
+				// The new url will be to the same file.
+				nfsp.NetworkFileStream.SetUriForSameFile(new Uri(DownloadLicense.DownloadUrl));
+				return nfsp;
 			}
-			else
+			catch
 			{
-				nfsp = NewNetworkFilePersister();
+				FileUtility.SaferDelete(jsonDownloadState);
+				FileUtility.SaferDelete(tempFile);
+				return NewNetworkFilePersister();
 			}
-			return nfsp;
 		}
 
 		private NetworkFileStreamPersister NewNetworkFilePersister()
 		{
 			var headers = new System.Net.WebHeaderCollection
 			{
-				{ "User-Agent", downloadLicense.UserAgent }
+				{ "User-Agent", DownloadLicense.UserAgent }
 			};
 
-			var networkFileStream = new NetworkFileStream(tempFile, new Uri(downloadLicense.DownloadUrl), 0, headers);
+			var networkFileStream = new NetworkFileStream(tempFile, new Uri(DownloadLicense.DownloadUrl), 0, headers);
 			return new NetworkFileStreamPersister(networkFileStream, jsonDownloadState);
 		}
 	}

AaxDecrypter/MultiConvertFileProperties.cs

@@ -0,0 +1,25 @@
+using System;
+using System.IO;
+using FileManager;
+
+namespace AaxDecrypter
+{
+    public class MultiConvertFileProperties
+    {
+        public string OutputFileName { get; set; }
+        public int PartsPosition { get; set; }
+        public int PartsTotal { get; set; }
+        public string Title { get; set; }
+
+        public static string DefaultMultipartFilename(MultiConvertFileProperties multiConvertFileProperties)
+        {
+            var template = Path.ChangeExtension(multiConvertFileProperties.OutputFileName, null) + " - <ch# 0> - <title>" + Path.GetExtension(multiConvertFileProperties.OutputFileName);
+
+            var fileNamingTemplate = new FileNamingTemplate(template) { IllegalCharacterReplacements = " " };
+            fileNamingTemplate.AddParameterReplacement("ch# 0", FileUtility.GetSequenceFormatted(multiConvertFileProperties.PartsPosition, multiConvertFileProperties.PartsTotal));
+            fileNamingTemplate.AddParameterReplacement("title", multiConvertFileProperties.Title ?? "");
+
+            return fileNamingTemplate.GetFilePath();
+        }
+    }
+}

AaxDecrypter/NetworkFileStream.cs

@@ -193,9 +193,6 @@ namespace AaxDecrypter
             if (response.StatusCode != HttpStatusCode.PartialContent)
                 throw new WebException($"Server at {Uri.Host} responded with unexpected status code: {response.StatusCode}.");
 
-            if (response.Headers.GetValues("Accept-Ranges").FirstOrDefault(r => r.EqualsInsensitive("bytes")) is null)
-                throw new WebException($"Server at {Uri.Host} does not support Http ranges");
-
             //Content length is the length of the range request, and it is only equal
             //to the complete file length if requesting Range: bytes=0-
             if (WritePosition == 0)

AaxDecrypter/UnencryptedAudiobookDownloader.cs

@@ -1,56 +1,47 @@
-using Dinah.Core.IO;
+using System;
+using System.Threading;
 using Dinah.Core.Net.Http;
 using Dinah.Core.StepRunner;
-using System;
-using System.IO;
-using System.Linq;
-using System.Threading;
+using FileManager;
 
 namespace AaxDecrypter
 {
 	public class UnencryptedAudiobookDownloader : AudiobookDownloadBase
 	{
-		protected override StepSequence steps { get; }
+		protected override StepSequence Steps { get; }
 
 		public UnencryptedAudiobookDownloader(string outFileName, string cacheDirectory, DownloadLicense dlLic)
 			: base(outFileName, cacheDirectory, dlLic)
 		{
-
-			steps = new StepSequence
+			Steps = new StepSequence
 			{
 				Name = "Download Mp3 Audiobook",
 
-				["Step 1: Get Mp3 Metadata"] = Step1_GetMetadata,
-				["Step 2: Download Audiobook"] = Step2_DownloadAudiobookAsSingleFile,
-				["Step 3: Create Cue"] = Step3_CreateCue,
-				["Step 4: Cleanup"] = Step4_Cleanup,
+				["Step 1: Get Mp3 Metadata"] = Step_GetMetadata,
+				["Step 2: Download Audiobook"] = Step_DownloadAudiobookAsSingleFile,
+				["Step 3: Create Cue"] = Step_CreateCue,
+				["Step 4: Cleanup"] = Step_Cleanup,
 			};
 		}
 
 		public override void Cancel()
 		{
-			isCanceled = true;
+			IsCanceled = true;
 			CloseInputFileStream();
 		}
 
-		protected override int GetSpeedup(TimeSpan elapsed)
-		{
-			//Not implemented
-			return 0;
-		}
-
-		protected override bool Step1_GetMetadata()
+		protected bool Step_GetMetadata()
 		{
 			OnRetrievedCoverArt(null);
 
-			return !isCanceled;
+			return !IsCanceled;
 		}
 
-		protected override bool Step2_DownloadAudiobookAsSingleFile()
+		private bool Step_DownloadAudiobookAsSingleFile()
 		{
 			DateTime startTime = DateTime.Now;
 
-			//MUST put InputFileStream.Length first, because it starts background downloader.
+			// MUST put InputFileStream.Length first, because it starts background downloader.
 
 			while (InputFileStream.Length > InputFileStream.WritePosition && !InputFileStream.IsCancelled) 
 			{
@@ -75,12 +66,11 @@ namespace AaxDecrypter
 
 			CloseInputFileStream();
 
-			if (File.Exists(outputFileName))
-				FileExt.SafeDelete(outputFileName);
+			var realOutputFileName = FileUtility.SaferMoveToValidPath(InputFileStream.SaveFilePath, OutputFileName);
+			SetOutputFileName(realOutputFileName);
+			OnFileCreated(realOutputFileName);
 
-			FileExt.SafeMove(InputFileStream.SaveFilePath, outputFileName);
-
-			return !isCanceled;
+			return !IsCanceled;
 		}
 	}
 }

AppScaffolding/AppScaffolding.csproj

@@ -2,8 +2,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
-    <Version>6.2.3.0</Version>
+    <TargetFramework>net6.0-windows</TargetFramework>
+    <Version>7.0.0.1</Version>
   </PropertyGroup>
 
   <ItemGroup>
@@ -11,11 +11,11 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Octokit" Version="0.50.0" />
+    <PackageReference Include="Octokit" Version="0.51.0" />
   </ItemGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\InternalUtilities\InternalUtilities.csproj" />
+    <ProjectReference Include="..\AudibleUtilities\AudibleUtilities.csproj" />
   </ItemGroup>
 
 </Project>

AppScaffolding/LibationScaffolding.cs

@@ -3,11 +3,11 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using AudibleUtilities;
 using Dinah.Core;
 using Dinah.Core.IO;
 using Dinah.Core.Logging;
-using FileManager;
-using InternalUtilities;
+using LibationFileManager;
 using Newtonsoft.Json.Linq;
 using Serilog;
 
@@ -50,15 +50,48 @@ namespace AppScaffolding
 		public static void RunPostConfigMigrations(Configuration config)
 		{
 			AudibleApiStorage.EnsureAccountsSettingsFileExists();
+			PopulateMissingConfigValues(config);
 
 			//
 			// migrations go below here
 			//
 
-			Migrations.migrate_to_v5_2_0__post_config(config);
-			Migrations.migrate_to_v5_7_1(config);
-			Migrations.migrate_to_v6_1_2(config);
-			Migrations.migrate_to_v6_2_0(config);
+			Migrations.migrate_to_v6_6_9(config);
+		}
+
+		public static void PopulateMissingConfigValues(Configuration config)
+		{
+			config.InProgress ??= Configuration.WinTemp;
+
+			if (!config.Exists(nameof(config.AllowLibationFixup)))
+				config.AllowLibationFixup = true;
+
+			if (!config.Exists(nameof(config.DecryptToLossy)))
+				config.DecryptToLossy = false;
+
+			if (!config.Exists(nameof(config.BadBook)))
+				config.BadBook = Configuration.BadBookAction.Ask;
+
+			if (!config.Exists(nameof(config.DownloadEpisodes)))
+				config.DownloadEpisodes = true;
+
+			if (!config.Exists(nameof(config.ImportEpisodes)))
+				config.ImportEpisodes = true;
+
+			if (!config.Exists(nameof(config.SplitFilesByChapter)))
+				config.SplitFilesByChapter = false;
+
+			if (!config.Exists(nameof(config.FolderTemplate)))
+				config.FolderTemplate = Templates.Folder.DefaultTemplate;
+
+			if (!config.Exists(nameof(config.FileTemplate)))
+				config.FileTemplate = Templates.File.DefaultTemplate;
+
+			if (!config.Exists(nameof(config.ChapterFileTemplate)))
+				config.ChapterFileTemplate = Templates.ChapterFile.DefaultTemplate;
+
+			if (!config.Exists(nameof(config.ShowImportedStats)))
+				config.ShowImportedStats = true;
 		}
 
 		/// <summary>Initialize logging. Run after migration</summary>
@@ -74,29 +107,12 @@ namespace AppScaffolding
 			if (config.GetObject("Serilog") != null)
 				return;
 
-			// "Serilog": {
-			//   "MinimumLevel": "Information"
-			//   "WriteTo": [
-			//     {
-			//       "Name": "Console"
-			//     },
-			//     {
-			//       "Name": "File",
-			//       "Args": {
-			//         "rollingInterval": "Day",
-			//         "outputTemplate": ...
-			//       }
-			//     }
-			//   ],
-			//   "Using": [ "Dinah.Core" ],
-			//   "Enrich": [ "WithCaller" ]
-			// }
 			var serilogObj = new JObject
 			{
 				{ "MinimumLevel", "Information" },
 				{ "WriteTo", new JArray
 					{
-						new JObject { {"Name", "Console" } },
+						// new JObject { {"Name", "Console" } }, // this has caused more problems than it's solved
 						new JObject
 						{
 							{ "Name", "File" },
@@ -111,14 +127,16 @@ namespace AppScaffolding
 									//   output example:             2019-11-26 08:48:40.224 -05:00 [DBG] Begin Libation
 									// - with class and method info: "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] (at {Caller}) {Message:lj}{NewLine}{Exception}";
 									//   output example:             2019-11-26 08:48:40.224 -05:00 [DBG] (at LibationWinForms.Program.init()) Begin Libation
-									{ "outputTemplate", "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] (at {Caller}) {Message:lj}{NewLine}{Exception}" }
+									// {Properties:j} needed for expanded exception logging
+									{ "outputTemplate", "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] (at {Caller}) {Message:lj}{NewLine}{Exception} {Properties:j}" }
 								}
 							}
 						}
 					}
 				},
-				{ "Using", new JArray{ "Dinah.Core" } }, // dll's name, NOT namespace
-				{ "Enrich", new JArray{ "WithCaller" } },
+				// better exception logging with: Serilog.Exceptions library -- WithExceptionDetails
+				{ "Using", new JArray{ "Dinah.Core", "Serilog.Exceptions" } }, // dll's name, NOT namespace
+				{ "Enrich", new JArray{ "WithCaller", "WithExceptionDetails" } },
 			};
 			config.SetObject("Serilog", serilogObj);
 		}
@@ -133,9 +151,9 @@ namespace AppScaffolding
 			// capture most Console.WriteLine() and write to serilog. See below tests for details.
 			// Some dependencies print helpful info via Console.WriteLine. We'd like to log it.
 			//
-			// Serilog also writes to Console so this might be asking for trouble. ie: infinite loops.
-			// SerilogTextWriter needs to be more robust and tested. Esp the Write() methods.
-			// Empirical testing so far has shown no issues.
+			// If Serilog also writes to Console, this might be asking for trouble. ie: infinite loops.
+			// To use that way, SerilogTextWriter needs to be more robust and tested. Esp the Write() methods.
+			// However, empirical testing so far has shown no issues.
 			Console.SetOut(new MultiTextWriter(origOut, new SerilogTextWriter()));
 
 			#region Console => Serilog tests
@@ -211,11 +229,11 @@ namespace AppScaffolding
 
 				config.InProgress,
 
-				DownloadsInProgressDir = AudibleFileStorage.DownloadsInProgress,
-				DownloadsInProgressFiles = Directory.EnumerateFiles(AudibleFileStorage.DownloadsInProgress).Count(),
+				AudibleFileStorage.DownloadsInProgressDirectory,
+				DownloadsInProgressFiles = FileManager.FileUtility.SaferEnumerateFiles(AudibleFileStorage.DownloadsInProgressDirectory).Count(),
 
-				DecryptInProgressDir = AudibleFileStorage.DecryptInProgress,
-				DecryptInProgressFiles = Directory.EnumerateFiles(AudibleFileStorage.DecryptInProgress).Count(),
+				AudibleFileStorage.DecryptInProgressDirectory,
+				DecryptInProgressFiles = FileManager.FileUtility.SaferEnumerateFiles(AudibleFileStorage.DecryptInProgressDirectory).Count(),
 			});
 		}
 
@@ -311,39 +329,53 @@ namespace AppScaffolding
 				"WinTemp" => Path.GetFullPath(Path.Combine(Path.GetTempPath(), "Libation")),
 				_ => path
 			};
-
-		public static void migrate_to_v5_2_0__post_config(Configuration config)
-		{
-			if (!config.Exists(nameof(config.AllowLibationFixup)))
-				config.AllowLibationFixup = true;
-
-			if (!config.Exists(nameof(config.DecryptToLossy)))
-				config.DecryptToLossy = false;
-		}
 		#endregion
 
-		// add config.BadBook
-		public static void migrate_to_v5_7_1(Configuration config)
+		public static void migrate_to_v6_6_9(Configuration config)
 		{
-			if (!config.Exists(nameof(config.BadBook)))
-				config.BadBook = Configuration.BadBookAction.Ask;
-		}
+			var writeToPath = $"Serilog.WriteTo";
 
-		// add config.DownloadEpisodes , config.ImportEpisodes
-		public static void migrate_to_v6_1_2(Configuration config)
-		{
-			if (!config.Exists(nameof(config.DownloadEpisodes)))
-				config.DownloadEpisodes = true;
+			// remove WriteTo[].Name == Console
+			{
+				if (UNSAFE_MigrationHelper.Settings_TryGetArrayLength(writeToPath, out var length1))
+				{
+					for (var i = length1 - 1; i >= 0; i--)
+					{
+						var exists = UNSAFE_MigrationHelper.Settings_TryGetFromJsonPath($"{writeToPath}[{i}].Name", out var value);
 
-			if (!config.Exists(nameof(config.ImportEpisodes)))
-				config.ImportEpisodes = true;
-		}
+						if (exists && value == "Console")
+							UNSAFE_MigrationHelper.Settings_RemoveFromArray(writeToPath, i);
+					}
+				}
+			}
 
-		// add config.SplitFilesByChapter
-		public static void migrate_to_v6_2_0(Configuration config)
-		{
-			if (!config.Exists(nameof(config.SplitFilesByChapter)))
-				config.SplitFilesByChapter = false;
+			// add Serilog.Exceptions -- WithExceptionDetails
+			{
+				// outputTemplate should contain "{Properties:j}"
+				{
+					// re-calculate. previous loop may have changed the length
+					if (UNSAFE_MigrationHelper.Settings_TryGetArrayLength(writeToPath, out var length2))
+					{
+						var propertyName = "outputTemplate";
+						for (var i = 0; i < length2; i++)
+						{
+							var jsonPath = $"{writeToPath}[{i}].Args";
+							var exists = UNSAFE_MigrationHelper.Settings_TryGetFromJsonPath($"{jsonPath}.{propertyName}", out var value);
+
+							var newValue = "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] (at {Caller}) {Message:lj}{NewLine}{Exception} {Properties:j}";
+
+							if (exists && value != newValue)
+								UNSAFE_MigrationHelper.Settings_SetWithJsonPath(jsonPath, propertyName, newValue);
+						}
+					}
+				}
+
+				// Serilog.Using must include "Serilog.Exceptions"
+				UNSAFE_MigrationHelper.Settings_AddUniqueToArray("Serilog.Using", "Serilog.Exceptions");
+
+				// Serilog.Enrich must include "WithExceptionDetails"
+				UNSAFE_MigrationHelper.Settings_AddUniqueToArray("Serilog.Enrich", "WithExceptionDetails");
+			}
 		}
 	}
 }

AppScaffolding/UNSAFE_MigrationHelper.cs

@@ -113,6 +113,108 @@ namespace AppScaffolding
 			return success;
 		}
 
+		public static bool Settings_JsonPathIsType(string jsonPath, JTokenType jTokenType)
+		{
+			JToken val = null;
+
+			process_SettingsJson(jObj => val = jObj.SelectToken(jsonPath), false);
+
+			return val?.Type == jTokenType;
+		}
+
+		public static bool Settings_TryGetFromJsonPath(string jsonPath, out string value)
+		{
+			JToken val = null;
+
+			process_SettingsJson(jObj => val = jObj.SelectToken(jsonPath), false);
+
+			if (val?.Type == JTokenType.String)
+			{
+				value = val.Value<string>();
+				return true;
+			}
+			else
+			{
+				value = null;
+				return false;
+			}
+		}
+
+		public static void Settings_SetWithJsonPath(string jsonPath, string propertyName, string newValue)
+		{
+			if (!Settings_TryGetFromJsonPath($"{jsonPath}.{propertyName}", out _))
+				return;
+
+			process_SettingsJson(jObj =>
+			{
+				var token = jObj.SelectToken(jsonPath);
+				if (token is null
+				|| token is not JObject o
+				|| o[propertyName] is null)
+					return;
+
+				var oldValue = token.Value<string>(propertyName);
+				if (oldValue != newValue)
+					token[propertyName] = newValue;
+			});
+		}
+
+		public static bool Settings_TryGetArrayLength(string jsonPath, out int length)
+		{
+			length = 0;
+
+			if (!Settings_JsonPathIsType(jsonPath, JTokenType.Array))
+				return false;
+
+			JArray array = null;
+			process_SettingsJson(jObj => array = (JArray)jObj.SelectToken(jsonPath));
+
+			length = array.Count;
+			return true;
+		}
+
+		public static void Settings_AddToArray(string jsonPath, string newValue)
+		{
+			if (!Settings_JsonPathIsType(jsonPath, JTokenType.Array))
+				return;
+
+			process_SettingsJson(jObj =>
+			{
+				var array = (JArray)jObj.SelectToken(jsonPath);
+				array.Add(newValue);
+			});
+		}
+
+		/// <summary>Do not add if already exists</summary>
+		public static void Settings_AddUniqueToArray(string arrayPath, string newValue)
+		{
+			if (!Settings_TryGetArrayLength(arrayPath, out var qty))
+				return;
+
+			for (var i = 0; i < qty; i++)
+			{
+				var exists = Settings_TryGetFromJsonPath($"{arrayPath}[{i}]", out var value);
+				if (exists && value == newValue)
+					return;
+			}
+
+			Settings_AddToArray(arrayPath, newValue);
+		}
+
+		/// <summary>only remove if not exists</summary>
+		public static void Settings_RemoveFromArray(string jsonPath, int position)
+		{
+			if (!Settings_JsonPathIsType(jsonPath, JTokenType.Array))
+				return;
+
+			process_SettingsJson(jObj =>
+			{
+				var array = (JArray)jObj.SelectToken(jsonPath);
+				if (position < array.Count)
+					array.RemoveAt(position);
+			});
+		}
+
 		/// <summary>only insert if not exists</summary>
 		public static void Settings_Insert(string key, string value)
 			=> process_SettingsJson(jObj => jObj.TryAdd(key, value));

ApplicationServices/ApplicationServices.csproj

@@ -1,12 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="CsvHelper" Version="27.1.1" />
-    <PackageReference Include="NPOI" Version="2.5.4" />
+    <PackageReference Include="CsvHelper" Version="27.2.1" />
+    <PackageReference Include="NPOI" Version="2.5.6" />
   </ItemGroup>
 
   <ItemGroup>

ApplicationServices/DbContexts.cs

@@ -1,7 +1,7 @@
 using System;
 using System.Collections.Generic;
 using DataLayer;
-using FileManager;
+using LibationFileManager;
 
 namespace ApplicationServices
 {

ApplicationServices/LibraryCommands.cs

@@ -3,10 +3,11 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 using AudibleApi;
+using AudibleUtilities;
 using DataLayer;
 using Dinah.Core;
 using DtoImporterService;
-using InternalUtilities;
+using LibationFileManager;
 using Serilog;
 using static DtoImporterService.PerfLogger;
 
@@ -43,7 +44,7 @@ namespace ApplicationServices
 			}
 			catch (AudibleApi.Authentication.LoginFailedException lfEx)
 			{
-				lfEx.SaveFiles(FileManager.Configuration.Instance.LibationFiles);
+				lfEx.SaveFiles(Configuration.Instance.LibationFiles);
 
 				// nuget Serilog.Exceptions would automatically log custom properties
 				//   However, it comes with a scary warning when used with EntityFrameworkCore which I'm not yet ready to implement:
@@ -88,6 +89,9 @@ namespace ApplicationServices
 				var totalCount = importItems.Count;
 				Log.Logger.Information($"GetAllLibraryItems: Total count {totalCount}");
 
+				if (totalCount == 0)
+					return default;
+
 				Log.Logger.Information("Begin long-running import");
 				logTime($"pre {nameof(importIntoDbAsync)}");
 				var newCount = await importIntoDbAsync(importItems);
@@ -98,7 +102,7 @@ namespace ApplicationServices
 			}
 			catch (AudibleApi.Authentication.LoginFailedException lfEx)
 			{
-				lfEx.SaveFiles(FileManager.Configuration.Instance.LibationFiles);
+				lfEx.SaveFiles(Configuration.Instance.LibationFiles);
 
 				// nuget Serilog.Exceptions would automatically log custom properties
 				//   However, it comes with a scary warning when used with EntityFrameworkCore which I'm not yet ready to implement:
@@ -155,7 +159,7 @@ namespace ApplicationServices
 
 			logTime($"pre scanAccountAsync {account.AccountName}");
 
-			var dtoItems = await apiExtended.GetLibraryValidatedAsync(libraryResponseGroups, FileManager.Configuration.Instance.ImportEpisodes);
+			var dtoItems = await apiExtended.GetLibraryValidatedAsync(libraryResponseGroups, Configuration.Instance.ImportEpisodes);
 
 			logTime($"post scanAccountAsync {account.AccountName} qty: {dtoItems.Count}");
 
@@ -163,25 +167,46 @@ namespace ApplicationServices
 		}
 
 		private static async Task<int> importIntoDbAsync(List<ImportItem> importItems)
+        {
+            logTime("importIntoDbAsync -- pre db");
+            using var context = DbContexts.GetContext();
+            var libraryBookImporter = new LibraryBookImporter(context);
+            var newCount = await Task.Run(() => libraryBookImporter.Import(importItems));
+            logTime("importIntoDbAsync -- post Import()");
+            int qtyChanges = saveChanges(context);
+            logTime("importIntoDbAsync -- post SaveChanges");
+
+            if (qtyChanges > 0)
+                await Task.Run(() => finalizeLibrarySizeChange());
+            logTime("importIntoDbAsync -- post finalizeLibrarySizeChange");
+
+            return newCount;
+        }
+
+        private static int saveChanges(LibationContext context)
 		{
-			logTime("importIntoDbAsync -- pre db");
-			using var context = DbContexts.GetContext();
-			var libraryImporter = new LibraryBookImporter(context);
-			var newCount = await Task.Run(() => libraryImporter.Import(importItems));
-			logTime("importIntoDbAsync -- post Import()");
-			var qtyChanges = context.SaveChanges();
-			logTime("importIntoDbAsync -- post SaveChanges");
+			try
+			{
+				return context.SaveChanges();
+			}
+			catch (Microsoft.EntityFrameworkCore.DbUpdateException ex)
+			{
+				// DbUpdateException exceptions can wreck serilog. Condense it until we can find a better solution. I suspect the culpret is the "WithExceptionDetails" serilog extension
 
-			if (qtyChanges > 0)
-				await Task.Run(() => finalizeLibrarySizeChange());
-			logTime("importIntoDbAsync -- post finalizeLibrarySizeChange");
+				static string format(Exception ex) => $"\r\nMessage: {ex.Message}\r\nStack Trace:\r\n{ex.StackTrace}";
 
-			return newCount;
-		}
-		#endregion
+				var msg = "Microsoft.EntityFrameworkCore.DbUpdateException";
+				if (ex.InnerException is null)
+					throw new Exception($"{msg}{format(ex)}");
+				throw new Exception(
+					$"{msg}{format(ex)}",
+					new Exception($"Inner Exception{format(ex.InnerException)}"));
+			}
+        }
+        #endregion
 
-		#region remove books
-		public static Task<List<LibraryBook>> RemoveBooksAsync(List<string> idsToRemove) => Task.Run(() => removeBooks(idsToRemove));
+        #region remove books
+        public static Task<List<LibraryBook>> RemoveBooksAsync(List<string> idsToRemove) => Task.Run(() => removeBooks(idsToRemove));
 		private static List<LibraryBook> removeBooks(List<string> idsToRemove)
 		{
 			using var context = DbContexts.GetContext();
@@ -228,6 +253,7 @@ namespace ApplicationServices
 				if (qtyChanges > 0)
 				{
 					SearchEngineCommands.UpdateLiberatedStatus(book);
+					SearchEngineCommands.UpdateBookTags(book);
 					BookUserDefinedItemCommitted?.Invoke(null, book.AudibleProductId);
 				}
 
@@ -244,7 +270,7 @@ namespace ApplicationServices
 		// must be here instead of in db layer due to AaxcExists
 		public static LiberatedStatus Liberated_Status(Book book)
 			=> book.Audio_Exists ? book.UserDefinedItem.BookStatus
-			: FileManager.AudibleFileStorage.AaxcExists(book.AudibleProductId) ? LiberatedStatus.PartialDownload
+			: AudibleFileStorage.AaxcExists(book.AudibleProductId) ? LiberatedStatus.PartialDownload
 			: LiberatedStatus.NotLiberated;
 
 		// exists here for feature predictability. It makes sense for this to be where Liberated_Status is

ApplicationServices/LibraryExporter.cs

@@ -44,6 +44,9 @@ namespace ApplicationServices
 		[Name("Length In Minutes")]
 		public int LengthInMinutes { get; set; }
 
+		[Name("Description")]
+		public string Description { get; set; }
+
 		[Name("Publisher")]
 		public string Publisher { get; set; }
 
@@ -111,6 +114,7 @@ namespace ApplicationServices
 				AuthorNames = a.Book.AuthorNames,
 				NarratorNames = a.Book.NarratorNames,
 				LengthInMinutes = a.Book.LengthInMinutes,
+				Description = a.Book.Description,
 				Publisher = a.Book.Publisher,
 				HasPdf = a.Book.HasPdf,
 				SeriesNames = a.Book.SeriesNames,
@@ -180,6 +184,7 @@ namespace ApplicationServices
 				nameof (ExportDto.AuthorNames),
 				nameof (ExportDto.NarratorNames),
 				nameof (ExportDto.LengthInMinutes),
+				nameof (ExportDto.Description),
 				nameof (ExportDto.Publisher),
 				nameof (ExportDto.HasPdf),
 				nameof (ExportDto.SeriesNames),
@@ -233,6 +238,7 @@ namespace ApplicationServices
 				row.CreateCell(col++).SetCellValue(dto.AuthorNames);
 				row.CreateCell(col++).SetCellValue(dto.NarratorNames);
 				row.CreateCell(col++).SetCellValue(dto.LengthInMinutes);
+				row.CreateCell(col++).SetCellValue(dto.Description);
 				row.CreateCell(col++).SetCellValue(dto.Publisher);
 				row.CreateCell(col++).SetCellValue(dto.HasPdf);
 				row.CreateCell(col++).SetCellValue(dto.SeriesNames);

AudibleUtilities/Account.cs

@@ -6,7 +6,7 @@ using AudibleApi.Authorization;
 using Dinah.Core;
 using Newtonsoft.Json;
 
-namespace InternalUtilities
+namespace AudibleUtilities
 {
 	public class Account : IUpdatable
 	{

AudibleUtilities/AccountsSettings.cs

@@ -6,7 +6,7 @@ using AudibleApi.Authorization;
 using Dinah.Core;
 using Newtonsoft.Json;
 
-namespace InternalUtilities
+namespace AudibleUtilities
 {
 	// 'AccountsSettings' is intentionally NOT IEnumerable<> so that properties can be added/extended
 	// from newtonsoft (https://www.newtonsoft.com/json/help/html/SerializationGuide.htm):

AudibleUtilities/AccountsSettingsPersister.cs

@@ -3,7 +3,7 @@ using AudibleApi.Authorization;
 using Dinah.Core.IO;
 using Newtonsoft.Json;
 
-namespace InternalUtilities
+namespace AudibleUtilities
 {
 	public class AccountsSettingsPersister : JsonFilePersister<AccountsSettings>
 	{

AudibleUtilities/ApiExtended.cs

@@ -8,7 +8,7 @@ using Dinah.Core;
 using Polly;
 using Polly.Retry;
 
-namespace InternalUtilities
+namespace AudibleUtilities
 {
 	/// <summary>USE THIS from within Libation. It wraps the call with correct JSONPath</summary>
 	public class ApiExtended
@@ -127,11 +127,18 @@ namespace InternalUtilities
 //    items = AudibleApi.Common.Converter.FromJson<List<Item>>(System.IO.File.ReadAllText(library_json));
 //}
 #endif
+
+			Serilog.Log.Logger.Debug("Begin initial library scan");
+
 			if (!items.Any())
 				items = await Api.GetAllLibraryItemsAsync(responseGroups);
 
+			Serilog.Log.Logger.Debug("Initial library scan complete. Begin episode scan");
+
 			await manageEpisodesAsync(items, importEpisodes);
 
+			Serilog.Log.Logger.Debug("Episode scan complete");
+
 #if DEBUG
 //System.IO.File.WriteAllText(library_json, AudibleApi.Common.Converter.ToJson(items));
 #endif
@@ -166,8 +173,7 @@ namespace InternalUtilities
 
 				Serilog.Log.Logger.Information($"{parents.Count} series of shows/podcasts found");
 
-				// remove episode parents. even if the following stuff fails, these will still be removed from the collection.
-				// also must happen before processing children because children abuses this flag
+				// remove episode parents. even if the following stuff fails, these will still be removed from the collection
 				items.RemoveAll(i => i.IsEpisodes);
 
 				if (importEpisodes)
@@ -192,6 +198,14 @@ namespace InternalUtilities
 			{
 				var children = await getEpisodeChildrenAsync(parent);
 
+				// actual individual episode, not the parent of a series.
+				// for now I'm keeping it inside this method since it fits the work flow, incl. importEpisodes logic
+				if (!children.Any())
+				{
+					results.Add(parent);
+					continue;
+				}
+
 				foreach (var child in children)
 				{
 					// use parent's 'DateAdded'. DateAdded is just a convenience prop for: PurchaseDate.UtcDateTime
@@ -202,7 +216,8 @@ namespace InternalUtilities
 						new Series
 						{
 							Asin = parent.Asin,
-							Sequence = parent.Relationships.Single(r => r.Asin == child.Asin).Sort.ToString(),
+							// This should properly be Single() not FirstOrDefault(), but FirstOrDefault is defensive for malformed data from audible
+							Sequence = parent.Relationships.FirstOrDefault(r => r.Asin == child.Asin).Sort.ToString(),
 							Title = parent.TitleWithSubtitle
 						}
 					};

AudibleUtilities/AudibleApiStorage.cs

@@ -1,9 +1,9 @@
 using System;
 using System.IO;
-using FileManager;
+using LibationFileManager;
 using Newtonsoft.Json;
 
-namespace InternalUtilities
+namespace AudibleUtilities
 {
 	public static class AudibleApiStorage
 	{

AudibleUtilities/AudibleApiValidators.cs

@@ -3,7 +3,7 @@ using System.Collections.Generic;
 using System.Linq;
 using AudibleApi.Common;
 
-namespace InternalUtilities
+namespace AudibleUtilities
 {
 	public interface IValidator
 	{

AudibleUtilities/AudibleUtilities.csproj

@@ -0,0 +1,15 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0-windows</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="AudibleApi" Version="2.7.3.1" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\LibationFileManager\LibationFileManager.csproj" />
+  </ItemGroup>
+
+</Project>

AudibleUtilities/_InternalsVisible.cs

@@ -0,0 +1 @@
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo(nameof(AudibleUtilities) + ".Tests")]

DataLayer/Configurations/BookContributorConfig.cs

@@ -9,8 +9,8 @@ namespace DataLayer.Configurations
         {
             entity.HasKey(bc => new { bc.BookId, bc.ContributorId, bc.Role });
 
-            entity.HasIndex(b => b.BookId);
-            entity.HasIndex(b => b.ContributorId);
+            entity.HasIndex(bc => bc.BookId);
+            entity.HasIndex(bc => bc.ContributorId);
 
             entity
                 .HasOne(bc => bc.Book)

DataLayer/Configurations/LibraryBookConfig.cs

@@ -21,12 +21,12 @@ namespace DataLayer.Configurations
             // - update LibraryBook import code
             // - would likely challenge assumptions throughout Libation which have been true up until now
 
-            entity.HasKey(b => b.BookId);
+            entity.HasKey(lb => lb.BookId);
 
             entity
-                .HasOne(le => le.Book)
+                .HasOne(lb => lb.Book)
                 .WithOne()
-                .HasForeignKey<LibraryBook>(le => le.BookId);
+                .HasForeignKey<LibraryBook>(lb => lb.BookId);
         }
     }
 }

DataLayer/Configurations/SeriesBookConfig.cs

@@ -7,10 +7,10 @@ namespace DataLayer.Configurations
     {
         public void Configure(EntityTypeBuilder<SeriesBook> entity)
         {
-            entity.HasKey(bc => new { bc.SeriesId, bc.BookId });
+            entity.HasKey(sb => new { sb.SeriesId, sb.BookId });
 
-            entity.HasIndex(b => b.SeriesId);
-            entity.HasIndex(b => b.BookId);
+            entity.HasIndex(sb => sb.SeriesId);
+            entity.HasIndex(sb => sb.BookId);
 
             entity
                 .HasOne(sb => sb.Series)

DataLayer/Configurations/SeriesConfig.cs

@@ -7,8 +7,8 @@ namespace DataLayer.Configurations
     {
         public void Configure(EntityTypeBuilder<Series> entity)
         {
-            entity.HasKey(b => b.SeriesId);
-            entity.HasIndex(b => b.AudibleSeriesId);
+            entity.HasKey(s => s.SeriesId);
+            entity.HasIndex(s => s.AudibleSeriesId);
 
             entity
                 .Metadata

DataLayer/DataLayer.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup>
@@ -12,20 +12,20 @@
   </PropertyGroup>
   
   <ItemGroup>
-    <PackageReference Include="Dinah.EntityFrameworkCore" Version="1.0.5.2" />
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="5.0.10">
+    <PackageReference Include="Dinah.EntityFrameworkCore" Version="4.0.0.3" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="6.0.4">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="5.0.10" />
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="5.0.10">
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="6.0.4" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="6.0.4">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
   </ItemGroup>
   
   <ItemGroup>
-    <ProjectReference Include="..\FileManager\FileManager.csproj" />
+    <ProjectReference Include="..\LibationFileManager\LibationFileManager.csproj" />
   </ItemGroup>
   
   <ItemGroup>

DataLayer/EfClasses/Book.cs

@@ -185,6 +185,9 @@ namespace DataLayer
         {
             get
             {
+                if (_seriesLink is null)
+                    return "";
+
                 // first: alphabetical by name
                 var withNames = _seriesLink
                     .Where(s => !string.IsNullOrWhiteSpace(s.Series.Name))

DataLayer/EfClasses/Category.cs

@@ -18,7 +18,7 @@ namespace DataLayer
     public class Category
     {
         // Empty is a special case. use private ctor w/o validation
-        public static Category GetEmpty() => new Category { CategoryId = -1, AudibleCategoryId = "", Name = "" };
+        public static Category GetEmpty() => new() { CategoryId = -1, AudibleCategoryId = "", Name = "" };
 
         internal int CategoryId { get; private set; }
         public string AudibleCategoryId { get; private set; }

DataLayer/EfClasses/Contributor.cs

@@ -7,7 +7,7 @@ namespace DataLayer
     public class Contributor
 	{
 		// Empty is a special case. use private ctor w/o validation
-		public static Contributor GetEmpty() => new Contributor { ContributorId = -1, Name = "" };
+		public static Contributor GetEmpty() => new() { ContributorId = -1, Name = "" };
 
 		// contributors search links are just name with url-encoding. space can be + or %20
 		//   author search link:   /search?searchAuthor=Robert+Bevan
@@ -31,16 +31,12 @@ namespace DataLayer
         public string AudibleContributorId { get; private set; }
 
         private Contributor() { }
-        public Contributor(string name)
+        public Contributor(string name, string audibleContributorId = null)
         {
-            ArgumentValidator.EnsureNotNullOrWhiteSpace(name, nameof(name));
+            Name = ArgumentValidator.EnsureNotNullOrWhiteSpace(name, nameof(name));
 
             _booksLink = new HashSet<BookContributor>();
 
-            Name = name;
-        }
-		public Contributor(string name, string audibleContributorId) : this(name)
-		{
 			// don't overwrite with null or whitespace but not an error
 			if (!string.IsNullOrWhiteSpace(audibleContributorId))
 				AudibleContributorId = audibleContributorId;

DataLayer/EfClasses/UserDefinedItem.cs

@@ -33,7 +33,7 @@ namespace DataLayer
 
 			// import previously saved tags
 			ArgumentValidator.EnsureNotNullOrWhiteSpace(book.AudibleProductId, nameof(book.AudibleProductId));
-			Tags = FileManager.TagsPersistence.GetTags(book.AudibleProductId);
+			Tags = LibationFileManager.TagsPersistence.GetTags(book.AudibleProductId);
 		}
 
         #region Tags

DataLayer/QueryObjects/BookQueries.cs

@@ -19,7 +19,8 @@ namespace DataLayer
         public static Book GetBook(this IQueryable<Book> books, string productId)
             => books
                 .GetBooks()
-                .SingleOrDefault(b => b.AudibleProductId == productId);
+                // 'Single' is more accurate but 'First' is faster and less error prone
+                .FirstOrDefault(b => b.AudibleProductId == productId);
 
         /// <summary>This is still IQueryable. YOU MUST CALL ToList() YOURSELF</summary>
         public static IQueryable<Book> GetBooks(this IQueryable<Book> books, Expression<Func<Book, bool>> predicate)

DataLayer/TagPersistenceInterceptor.cs

@@ -24,7 +24,7 @@ namespace DataLayer
 				.Select(t => (t.Book.AudibleProductId, t.Tags))
 				.ToList();
 
-			FileManager.TagsPersistence.Save(tagsCollection);
+			LibationFileManager.TagsPersistence.Save(tagsCollection);
 		}
 	}
 }

DataLayer/Utilities/LocalDatabaseInfo.cs

@@ -1,38 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-
-namespace DataLayer.Utilities
-{
-	public static class LocalDatabaseInfo
-	{
-		public static List<string> GetLocalDBInstances()
-		{
-			// Start the child process.
-			using var p = new System.Diagnostics.Process
-			{
-				StartInfo = new System.Diagnostics.ProcessStartInfo
-				{
-					UseShellExecute = false,
-					RedirectStandardOutput = true,
-					FileName = "cmd.exe",
-					Arguments = "/C sqllocaldb info",
-					CreateNoWindow = true,
-					WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden
-				}
-			};
-			p.Start();
-			var output = p.StandardOutput.ReadToEnd();
-			p.WaitForExit();
-
-			// if LocalDb is not installed then it will return that 'sqllocaldb' is not recognized as an internal or external command operable program or batch file
-			return string.IsNullOrWhiteSpace(output) || output.Contains("not recognized")
-				? new List<string>()
-				: output
-					.Split(new string[] { Environment.NewLine }, StringSplitOptions.None)
-					.Select(i => i.Trim())
-					.Where(i => !string.IsNullOrEmpty(i))
-					.ToList();
-		}
-	}
-}

DtoImporterService/BookImporter.cs

@@ -2,64 +2,55 @@
 using System.Collections.Generic;
 using System.Linq;
 using AudibleApi.Common;
+using AudibleUtilities;
 using DataLayer;
-using InternalUtilities;
+using Dinah.Core.Collections.Generic;
 
 namespace DtoImporterService
 {
 	public class BookImporter : ItemsImporterBase
 	{
-		public BookImporter(LibationContext context) : base(context) { }
+		protected override IValidator Validator => new BookValidator();
 
-		public override IEnumerable<Exception> Validate(IEnumerable<ImportItem> importItems) => new BookValidator().Validate(importItems.Select(i => i.DtoItem));
+		public Dictionary<string, Book> Cache { get; private set; } = new();
+
+		private ContributorImporter contributorImporter { get; }
+		private SeriesImporter seriesImporter { get; }
+		private CategoryImporter categoryImporter { get; }
+
+		public BookImporter(LibationContext context) : base(context)
+		{
+			contributorImporter = new ContributorImporter(DbContext);
+			seriesImporter = new SeriesImporter(DbContext);
+			categoryImporter = new CategoryImporter(DbContext);
+		}
 
 		protected override int DoImport(IEnumerable<ImportItem> importItems)
 		{
 			// pre-req.s
-			new ContributorImporter(DbContext).Import(importItems);
-			new SeriesImporter(DbContext).Import(importItems);
-			new CategoryImporter(DbContext).Import(importItems);
-			
-			// get distinct
-			var productIds = importItems.Select(i => i.DtoItem.ProductId).Distinct().ToList();
-			
-			// load db existing => .Local
-			loadLocal_books(productIds);
-			
+			contributorImporter.Import(importItems);
+			seriesImporter.Import(importItems);
+			categoryImporter.Import(importItems);
+
+			// load db existing => hash table
+			loadLocal_books(importItems);
+
 			// upsert
 			var qtyNew = upsertBooks(importItems);
 			return qtyNew;
 		}
 
-		private void loadLocal_books(List<string> productIds)
+		private void loadLocal_books(IEnumerable<ImportItem> importItems)
 		{
-			// if this context has already loaded books, don't need to reload them. vestige from when context was long-lived. in practice, we now typically use a fresh context. this is quick though so no harm in leaving it.
-			var localProductIds = DbContext.Books.Local.Select(b => b.AudibleProductId).ToList();
-			var remainingProductIds = productIds
-				.Except(localProductIds)
+			// get distinct
+			var productIds = importItems
+				.Select(i => i.DtoItem.ProductId)
+				.Distinct()
 				.ToList();
 
-			#region // explanation of DbContext.Books.GetBooks(b => remainingProductIds.Contains(b.AudibleProductId)).ToList();
-			/*
-			articles suggest loading to Local with
-			    context.Books.Load();
-			we want Books and associated fields
-			    context.Books.GetBooks(b => remainingProductIds.Contains(b.AudibleProductId)).ToList();
-			this is emulating Load() but with also getting associated fields
-
-			from: Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions
-			// Summary:
-			//     Enumerates the query. When using Entity Framework, this causes the results of
-			//     the query to be loaded into the associated context. This is equivalent to calling
-			//     ToList and then throwing away the list (without the overhead of actually creating
-			//     the list).
-			public static void Load<TSource>([NotNullAttribute] this IQueryable<TSource> source); 
-			*/
-			#endregion
-
-			// GetBooks() eager loads Series, category, et al
-			if (remainingProductIds.Any())
-				DbContext.Books.GetBooks(b => remainingProductIds.Contains(b.AudibleProductId)).ToList();
+			Cache = DbContext.Books
+				.GetBooks(b => productIds.Contains(b.AudibleProductId))
+				.ToDictionarySafe(b => b.AudibleProductId);
 		}
 
 		private int upsertBooks(IEnumerable<ImportItem> importItems)
@@ -68,8 +59,7 @@ namespace DtoImporterService
 
 			foreach (var item in importItems)
 			{
-				var book = DbContext.Books.Local.SingleOrDefault(p => p.AudibleProductId == item.DtoItem.ProductId);
-				if (book is null)
+				if (!Cache.TryGetValue(item.DtoItem.ProductId, out var book))
 				{
 					book = createNewBook(item);
 					qtyNew++;
@@ -94,7 +84,7 @@ namespace DtoImporterService
 			// nested logic is required so order of names is retained. else, contributors may appear in the order they were inserted into the db
 			var authors = item
 				.Authors
-				.Select(a => DbContext.Contributors.Local.Single(c => a.Name == c.Name))
+				.Select(a => contributorImporter.Cache[a.Name])
 				.ToList();
 
 			var narrators
@@ -104,7 +94,7 @@ namespace DtoImporterService
 				// nested logic is required so order of names is retained. else, contributors may appear in the order they were inserted into the db
 				: item
 					.Narrators
-					.Select(n => DbContext.Contributors.Local.Single(c => n.Name == c.Name))
+					.Select(n => contributorImporter.Cache[n.Name])
 					.ToList();
 
 			// categories are laid out for a breadcrumb. category is 1st, subcategory is 2nd
@@ -118,24 +108,44 @@ namespace DtoImporterService
 				// 2+
 				: item.Categories[1].CategoryId;
 
-			var category = DbContext.Categories.Local.SingleOrDefault(c => c.AudibleCategoryId == lastCategory);
+			var category = categoryImporter.Cache[lastCategory];
 
-			var book = DbContext.Books.Add(new Book(
-				new AudibleProductId(item.ProductId),
-				item.TitleWithSubtitle,
-				item.Description,
-				item.LengthInMinutes,
-				contentType,
-				authors,
-				narrators,
-				category,
-				importItem.LocaleName)
-			).Entity;
+			Book book;
+			try
+			{
+				book = DbContext.Books.Add(new Book(
+					new AudibleProductId(item.ProductId),
+					item.TitleWithSubtitle,
+					item.Description,
+					item.LengthInMinutes,
+					contentType,
+					authors,
+					narrators,
+					category,
+					importItem.LocaleName)
+					).Entity;
+				Cache.Add(book.AudibleProductId, book);
+			}
+			catch (Exception ex)
+			{
+				Serilog.Log.Logger.Error(ex, "Error adding book. {@DebugInfo}", new {
+					item.ProductId,
+					item.TitleWithSubtitle,
+					item.Description,
+					item.LengthInMinutes,
+					contentType,
+					QtyAuthors = authors?.Count,
+					QtyNarrators = narrators?.Count,
+					Category = category?.Name,
+					importItem.LocaleName
+				});
+				throw;
+			}
 
 			var publisherName = item.Publisher;
 			if (!string.IsNullOrWhiteSpace(publisherName))
 			{
-				var publisher = DbContext.Contributors.Local.Single(c => publisherName == c.Name);
+				var publisher = contributorImporter.Cache[publisherName];
 				book.ReplacePublisher(publisher);
 			}
 
@@ -152,7 +162,9 @@ namespace DtoImporterService
 			var item = importItem.DtoItem;
 
 			// set/update book-specific info which may have changed
-			book.PictureId = item.PictureId;
+			if (item.PictureId is not null)
+				book.PictureId = item.PictureId;
+
 			book.UpdateProductRating(item.Product_OverallStars, item.Product_PerformanceStars, item.Product_StoryStars);
 
 			// important to update user-specific info. this will have changed if user has rated/reviewed the book since last library import
@@ -164,7 +176,7 @@ namespace DtoImporterService
 			{
 				foreach (var seriesEntry in item.Series)
 				{
-					var series = DbContext.Series.Local.Single(s => seriesEntry.SeriesId == s.AudibleSeriesId);
+					var series = seriesImporter.Cache[seriesEntry.SeriesId];
 					book.UpsertSeries(series, seriesEntry.Sequence);
 				}
 			}

DtoImporterService/CategoryImporter.cs

@@ -2,16 +2,19 @@
 using System.Collections.Generic;
 using System.Linq;
 using AudibleApi.Common;
+using AudibleUtilities;
 using DataLayer;
-using InternalUtilities;
+using Dinah.Core.Collections.Generic;
 
 namespace DtoImporterService
 {
 	public class CategoryImporter : ItemsImporterBase
 	{
-		public CategoryImporter(LibationContext context) : base(context) { }
+		protected override IValidator Validator => new CategoryValidator();
 
-		public override IEnumerable<Exception> Validate(IEnumerable<ImportItem> importItems) => new CategoryValidator().Validate(importItems.Select(i => i.DtoItem));
+		public Dictionary<string, Category> Cache { get; private set; } = new();
+
+		public CategoryImporter(LibationContext context) : base(context) { }
 
 		protected override int DoImport(IEnumerable<ImportItem> importItems)
 		{
@@ -19,7 +22,9 @@ namespace DtoImporterService
 			var categoryIds = importItems
 				.Select(i => i.DtoItem)
 				.GetCategoriesDistinct()
-				.Select(c => c.CategoryId).ToList();
+				.Select(c => c.CategoryId)
+				.Distinct()
+				.ToList();
 
 			// load db existing => .Local
 			loadLocal_categories(categoryIds);
@@ -35,17 +40,13 @@ namespace DtoImporterService
 
 		private void loadLocal_categories(List<string> categoryIds)
 		{
-			var localIds = DbContext.Categories.Local.Select(c => c.AudibleCategoryId).ToList();
-			var remainingCategoryIds = categoryIds
-				.Distinct()
-				.Except(localIds)
-				.ToList();
+			// must include default/empty/missing
+			categoryIds.Add(Category.GetEmpty().AudibleCategoryId);
 
 			// load existing => local
-			// remember to include default/empty/missing
-			var emptyName = Contributor.GetEmpty().Name;
-			if (remainingCategoryIds.Any())
-				DbContext.Categories.Where(c => remainingCategoryIds.Contains(c.AudibleCategoryId) || c.Name == emptyName).ToList();
+			Cache = DbContext.Categories
+				.Where(c => categoryIds.Contains(c.AudibleCategoryId))
+				.ToDictionarySafe(c => c.AudibleCategoryId);
 		}
 
 		// only use after loading contributors => local
@@ -66,14 +67,11 @@ namespace DtoImporterService
 
 					Category parentCategory = null;
 					if (i == 1)
-						// should be "Single()" but user is getting a strange error
-						parentCategory = DbContext.Categories.Local.FirstOrDefault(c => c.AudibleCategoryId == pair[0].CategoryId);
+						Cache.TryGetValue(pair[0].CategoryId, out parentCategory);
 
-					// should be "SingleOrDefault()" but user is getting a strange error
-					var category = DbContext.Categories.Local.FirstOrDefault(c => c.AudibleCategoryId == id);
-					if (category is null)
+					if (!Cache.TryGetValue(id, out var category))
 					{
-						category = DbContext.Categories.Add(new Category(new AudibleCategoryId(id), name)).Entity;
+						category = addCategory(id, name);
 						qtyNew++;
 					}
 
@@ -83,5 +81,24 @@ namespace DtoImporterService
 
 			return qtyNew;
 		}
+
+		private Category addCategory(string id, string name)
+		{
+			try
+			{
+				var category = new Category(new AudibleCategoryId(id), name);
+
+				var entityEntry = DbContext.Categories.Add(category);
+				var entity = entityEntry.Entity;
+
+				Cache.Add(entity.AudibleCategoryId, entity);
+				return entity;
+			}
+			catch (Exception ex)
+			{
+				Serilog.Log.Logger.Error(ex, "Error adding category. {@DebugInfo}", new { id, name });
+				throw;
+			}
+		}
 	}
 }

DtoImporterService/ContributorImporter.cs

@@ -2,16 +2,19 @@
 using System.Collections.Generic;
 using System.Linq;
 using AudibleApi.Common;
+using AudibleUtilities;
 using DataLayer;
-using InternalUtilities;
+using Dinah.Core.Collections.Generic;
 
 namespace DtoImporterService
 {
 	public class ContributorImporter : ItemsImporterBase
 	{
-		public ContributorImporter(LibationContext context) : base(context) { }
+		protected override IValidator Validator => new ContributorValidator();
 
-		public override IEnumerable<Exception> Validate(IEnumerable<ImportItem> importItems) => new ContributorValidator().Validate(importItems.Select(i => i.DtoItem));
+		public Dictionary<string, Contributor> Cache { get; private set; } = new();
+
+		public ContributorImporter(LibationContext context) : base(context) { }
 
 		protected override int DoImport(IEnumerable<ImportItem> importItems)
 		{
@@ -50,58 +53,61 @@ namespace DtoImporterService
 			// must include default/empty/missing
 			contributorNames.Add(Contributor.GetEmpty().Name);
 
-			//// BAD: very inefficient
-			// var x = context.Contributors.Local.Where(c => !contribNames.Contains(c.Name));
-
-			// GOOD: Except() is efficient. Due to hashing, it's close to O(n)
-			var localNames = DbContext.Contributors.Local.Select(c => c.Name).ToList();
-			var remainingContribNames = contributorNames
-				.Distinct()
-				.Except(localNames)
-				.ToList();
-
 			// load existing => local
-			if (remainingContribNames.Any())
-				DbContext.Contributors.Where(c => remainingContribNames.Contains(c.Name)).ToList();
+			Cache = DbContext.Contributors
+				.Where(c => contributorNames.Contains(c.Name))
+				.ToDictionarySafe(c => c.Name);
 		}
 
-		// only use after loading contributors => local
 		private int upsertPeople(List<Person> people)
 		{
-			var localNames = DbContext.Contributors.Local.Select(c => c.Name).ToList();
-			var newPeople = people
-				.Select(p => p.Name)
-				.Distinct()
-				.Except(localNames)
-				.ToList();
+			var hash = people
+				// new people only
+				.Where(p => !Cache.ContainsKey(p.Name))
+				// remove duplicates by Name. first in wins
+				.ToDictionarySafe(p => p.Name);
 
-			var groupby = people.GroupBy(
-				p => p.Name,
-				p => p,
-				(key, g) => new { Name = key, People = g.ToList() }
-				);
-			foreach (var name in newPeople)
+			foreach (var kvp in hash)
 			{
-				var p = groupby.Single(g => g.Name == name).People.First();
-				DbContext.Contributors.Add(new Contributor(p.Name, p.Asin));
+				var person = kvp.Value;
+				addContributor(person.Name, person.Asin);
 			}
 
-			return newPeople.Count;
+			return hash.Count;
 		}
 
 		// only use after loading contributors => local
 		private int upsertPublishers(List<string> publishers)
 		{
-			var localNames = DbContext.Contributors.Local.Select(c => c.Name).ToList();
-			var newPublishers = publishers
-				.Distinct()
-				.Except(localNames)
-				.ToList();
+			var hash = publishers
+				// new publishers only
+				.Where(p => !Cache.ContainsKey(p))
+				// remove duplicates
+				.ToHashSet();
 
-			foreach (var pub in newPublishers)
-				DbContext.Contributors.Add(new Contributor(pub));
+			foreach (var pub in hash)
+				addContributor(pub);
 
-			return newPublishers.Count;
+			return hash.Count;
 		}
-	}
+
+        private Contributor addContributor(string name, string id = null)
+		{
+			try
+			{
+				var newContrib = new Contributor(name);
+
+				var entityEntry = DbContext.Contributors.Add(newContrib);
+				var entity = entityEntry.Entity;
+
+				Cache.Add(entity.Name, entity);
+				return entity;
+			}
+			catch (Exception ex)
+			{
+				Serilog.Log.Logger.Error(ex, "Error adding contributor. {@DebugInfo}", new { name, id });
+				throw;
+			}
+        }
+    }
 }

DtoImporterService/DtoImporterService.csproj

@@ -1,12 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
+    <ProjectReference Include="..\AudibleUtilities\AudibleUtilities.csproj" />
     <ProjectReference Include="..\DataLayer\DataLayer.csproj" />
-    <ProjectReference Include="..\InternalUtilities\InternalUtilities.csproj" />
   </ItemGroup>
 
 </Project>

DtoImporterService/ImporterBase.cs

@@ -1,9 +1,9 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using AudibleUtilities;
 using DataLayer;
 using Dinah.Core;
-using InternalUtilities;
 
 namespace DtoImporterService
 {
@@ -53,5 +53,9 @@ namespace DtoImporterService
 	public abstract class ItemsImporterBase : ImporterBase<IEnumerable<ImportItem>>
 	{
 		protected ItemsImporterBase(LibationContext context) : base(context) { }
+
+		protected abstract IValidator Validator { get; }
+        public sealed override IEnumerable<Exception> Validate(IEnumerable<ImportItem> importItems)
+			=> Validator.Validate(importItems.Select(i => i.DtoItem));
 	}
 }

DtoImporterService/LibraryBookImporter.cs

@@ -1,20 +1,26 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using AudibleUtilities;
 using DataLayer;
-using InternalUtilities;
+using Dinah.Core.Collections.Generic;
 
 namespace DtoImporterService
 {
 	public class LibraryBookImporter : ItemsImporterBase
 	{
-		public LibraryBookImporter(LibationContext context) : base(context) { }
+		protected override IValidator Validator => new LibraryValidator();
 
-		public override IEnumerable<Exception> Validate(IEnumerable<ImportItem> importItems) => new LibraryValidator().Validate(importItems.Select(i => i.DtoItem));
+		private BookImporter bookImporter { get; }
+
+		public LibraryBookImporter(LibationContext context) : base(context)
+		{
+			bookImporter = new BookImporter(DbContext);
+		}
 
 		protected override int DoImport(IEnumerable<ImportItem> importItems)
 		{
-			new BookImporter(DbContext).Import(importItems);
+			bookImporter.Import(importItems);
 
 			var qtyNew = upsertLibraryBooks(importItems);
 			return qtyNew;
@@ -35,18 +41,32 @@ namespace DtoImporterService
 			// CURRENT SOLUTION: don't re-insert
 
 			var currentLibraryProductIds = DbContext.LibraryBooks.Select(l => l.Book.AudibleProductId).ToList();
-			var newItems = importItems.Where(dto => !currentLibraryProductIds.Contains(dto.DtoItem.ProductId)).ToList();
+			var newItems = importItems
+				.Where(dto => !currentLibraryProductIds.Contains(dto.DtoItem.ProductId))
+				.ToList();
+
+			// if 2 accounts try to import the same book in the same transaction: error since we're only tracking and pulling by asin.
+			// just use the first
+			var hash = newItems.ToDictionarySafe(dto => dto.DtoItem.ProductId);
+			foreach (var kvp in hash)
+            {
+				var newItem = kvp.Value;
 
-			foreach (var newItem in newItems)
-			{
 				var libraryBook = new LibraryBook(
-					DbContext.Books.Local.Single(b => b.AudibleProductId == newItem.DtoItem.ProductId),
+					bookImporter.Cache[newItem.DtoItem.ProductId],
 					newItem.DtoItem.DateAdded,
 					newItem.AccountId);
-				DbContext.LibraryBooks.Add(libraryBook);
+				try
+				{
+					DbContext.LibraryBooks.Add(libraryBook);
+				}
+				catch (Exception ex)
+				{
+					Serilog.Log.Logger.Error(ex, "Error adding library book. {@DebugInfo}", new { libraryBook.Book, libraryBook.Account });
+				}
 			}
 
-			var qtyNew = newItems.Count;
+			var qtyNew = hash.Count;
 			return qtyNew;
 		}
 	}

DtoImporterService/PerfLogger.cs

@@ -8,8 +8,8 @@ namespace DtoImporterService
 	public record timeLogEntry(string msg, long totalElapsed, long delta);
 	public static class PerfLogger
 	{
-		private static Stopwatch sw = new Stopwatch();
-		private static List<timeLogEntry> __log { get; } = new List<timeLogEntry> { new("begin", 0, 0) };
+		private static Stopwatch sw { get; } = new();
+		private static List<timeLogEntry> __log { get; } = new() { new("begin", 0, 0) };
 
 		public static void logTime(string s)
 		{

DtoImporterService/SeriesImporter.cs

@@ -2,16 +2,19 @@
 using System.Collections.Generic;
 using System.Linq;
 using AudibleApi.Common;
+using AudibleUtilities;
 using DataLayer;
-using InternalUtilities;
+using Dinah.Core.Collections.Generic;
 
 namespace DtoImporterService
 {
 	public class SeriesImporter : ItemsImporterBase
 	{
-		public SeriesImporter(LibationContext context) : base(context) { }
+		protected override IValidator Validator => new SeriesValidator();
 
-		public override IEnumerable<Exception> Validate(IEnumerable<ImportItem> importItems) => new SeriesValidator().Validate(importItems.Select(i => i.DtoItem));
+		public Dictionary<string, DataLayer.Series> Cache { get; private set; } = new();
+
+		public SeriesImporter(LibationContext context) : base(context) { }
 
 		protected override int DoImport(IEnumerable<ImportItem> importItems)
 		{
@@ -31,15 +34,12 @@ namespace DtoImporterService
 
 		private void loadLocal_series(List<AudibleApi.Common.Series> series)
 		{
-			var seriesIds = series.Select(s => s.SeriesId).ToList();
-			var localIds = DbContext.Series.Local.Select(s => s.AudibleSeriesId).ToList();
-			var remainingSeriesIds = seriesIds
-				.Distinct()
-				.Except(localIds)
-				.ToList();
+			var seriesIds = series.Select(s => s.SeriesId).Distinct().ToList();
 
-			if (remainingSeriesIds.Any())
-				DbContext.Series.Where(s => remainingSeriesIds.Contains(s.AudibleSeriesId)).ToList();
+			if (seriesIds.Any())
+				Cache = DbContext.Series
+					.Where(s => seriesIds.Contains(s.AudibleSeriesId))
+					.ToDictionarySafe(s => s.AudibleSeriesId);
 		}
 
 		private int upsertSeries(List<AudibleApi.Common.Series> requestedSeries)
@@ -48,10 +48,10 @@ namespace DtoImporterService
 
 			foreach (var s in requestedSeries)
 			{
-				var series = DbContext.Series.Local.FirstOrDefault(c => c.AudibleSeriesId == s.SeriesId);
-				if (series is null)
+				// AudibleApi.Common.Series.SeriesId == DataLayer.AudibleSeriesId
+				if (!Cache.TryGetValue(s.SeriesId, out var series))
 				{
-					series = DbContext.Series.Add(new DataLayer.Series(new AudibleSeriesId(s.SeriesId))).Entity;
+					series = addSeries(s.SeriesId);
 					qtyNew++;
 				}
 				series.UpdateName(s.SeriesName);
@@ -59,5 +59,24 @@ namespace DtoImporterService
 
 			return qtyNew;
 		}
+
+		private DataLayer.Series addSeries(string seriesId)
+		{
+			try
+			{
+				var series = new DataLayer.Series(new AudibleSeriesId(seriesId));
+
+				var entityEntry = DbContext.Series.Add(series);
+				var entity = entityEntry.Entity;
+
+				Cache.Add(entity.AudibleSeriesId, entity);
+				return entity;
+			}
+			catch (Exception ex)
+			{
+				Serilog.Log.Logger.Error(ex, "Error adding series. {@DebugInfo}", new { seriesId });
+				throw;
+			}
+		}
 	}
 }

DtoImporterService/_importer notes.txt

@@ -0,0 +1,37 @@
+* Local (eg DbContext.Books.Local): indexes/hashes PK and nothing else. Local.Find(PK) is fast. All other searches (eg FirstOrDefault) have awful performance. It deceptively *feels* like we get this partially for free since added/modified entries live here.
+* live db: for all importers, fields used for lookup are indexed
+
+Using BookImporter as an example: since AudibleProductId is indexed, hitting the live db is much faster than using Local. Fastest is putting all in a local hash table
+
+Note: GetBook/GetBooks eager loads Series, category, et al
+
+for 1,200 iterations
+* load to LocalView
+  DbContext.Books.Local.FirstOrDefault(p => p.AudibleProductId == item.DtoItem.ProductId)
+  27,125 ms
+* read from live db
+  DbContext.Books.GetBook(item.DtoItem.ProductId)
+  12,224 ms
+* load to hash table: Dictionary<string, Book>
+  dictionary[item.DtoItem.ProductId];
+  1 ms (yes: ONE)
+
+With hashtable, somehow memory usage was not significantly affected
+
+-----------------------------------
+
+why were we using Local to begin with?
+
+articles suggest loading to Local with
+    context.Books.Load();
+this loads this table but not associated fields
+we want Books and associated fields
+    context.Books.GetBooks(b => remainingProductIds.Contains(b.AudibleProductId)).ToList();
+this is emulating Load() but with also getting associated fields
+			from: Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions
+			// Summary:
+			//     Enumerates the query. When using Entity Framework, this causes the results of
+			//     the query to be loaded into the associated context. This is equivalent to calling
+			//     ToList and then throwing away the list (without the overhead of actually creating
+			//     the list).
+			public static void Load<TSource>([NotNullAttribute] this IQueryable<TSource> source);

FileLiberator/AudioDecodable.cs

@@ -11,30 +11,33 @@ namespace FileLiberator
         public event EventHandler<byte[]> CoverImageDiscovered;
         public abstract void Cancel();
 
-        protected void OnRequestCoverArt(Action<byte[]> setCoverArtDel)
-		{
-            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(RequestCoverArt) });
-            RequestCoverArt?.Invoke(this, setCoverArtDel);
-        }
-
-        protected void OnTitleDiscovered(string title)
+        protected void OnTitleDiscovered(string title) => OnTitleDiscovered(null, title);
+        protected void OnTitleDiscovered(object _, string title)
 		{
             Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(TitleDiscovered), Title = title });
             TitleDiscovered?.Invoke(this, title);
 		}
 
-        protected void OnAuthorsDiscovered(string authors)
+        protected void OnAuthorsDiscovered(string authors) => OnAuthorsDiscovered(null, authors);
+        protected void OnAuthorsDiscovered(object _, string authors)
 		{
             Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(AuthorsDiscovered), Authors = authors });
             AuthorsDiscovered?.Invoke(this, authors);
 		}
 
-        protected void OnNarratorsDiscovered(string narrators)
+        protected void OnNarratorsDiscovered(string narrators) => OnNarratorsDiscovered(null, narrators);
+        protected void OnNarratorsDiscovered(object _, string narrators)
 		{
             Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(NarratorsDiscovered), Narrators = narrators });
             NarratorsDiscovered?.Invoke(this, narrators);
 		}
 
+        protected void OnRequestCoverArt(Action<byte[]> setCoverArtDel)
+		{
+            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(RequestCoverArt) });
+            RequestCoverArt?.Invoke(this, setCoverArtDel);
+        }
+
         protected void OnCoverImageDiscovered(byte[] coverImage)
 		{
             Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(CoverImageDiscovered), CoverImageBytes = coverImage?.Length });

FileLiberator/AudioFileStorageExt.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using DataLayer;
+using Dinah.Core;
+using FileManager;
+using LibationFileManager;
+
+namespace FileLiberator
+{
+    public static class AudioFileStorageExt
+    {
+        private class MultipartRenamer
+        {
+            private LibraryBook libraryBook { get; }
+
+            internal MultipartRenamer(LibraryBook libraryBook) => this.libraryBook = libraryBook;
+
+            internal string MultipartFilename(AaxDecrypter.MultiConvertFileProperties props)
+                => Templates.ChapterFile.GetFilename(libraryBook.ToDto(), props);
+        }
+
+        public static Func<AaxDecrypter.MultiConvertFileProperties, string> CreateMultipartRenamerFunc(this AudioFileStorage _, LibraryBook libraryBook)
+            => new MultipartRenamer(libraryBook).MultipartFilename;
+
+        /// <summary>
+        /// DownloadDecryptBook:
+        /// File path for where to move files into.
+        /// Path: directory nested inside of Books directory
+        /// File name: n/a
+        /// </summary>
+        public static string GetDestinationDirectory(this AudioFileStorage _, LibraryBook libraryBook)
+            => Templates.Folder.GetFilename(libraryBook.ToDto());
+
+        /// <summary>
+        /// DownloadDecryptBook:
+        /// Path: in progress directory.
+        /// File name: final file name.
+        /// </summary>
+        public static string GetInProgressFilename(this AudioFileStorage _, LibraryBook libraryBook, string extension)
+            => Templates.File.GetFilename(libraryBook.ToDto(), AudibleFileStorage.DecryptInProgressDirectory, extension);
+
+        /// <summary>
+        /// PDF: audio file does not exist
+        /// </summary>
+        public static string GetBooksDirectoryFilename(this AudioFileStorage _, LibraryBook libraryBook, string extension)
+            => Templates.File.GetFilename(libraryBook.ToDto(), AudibleFileStorage.BooksDirectory, extension);
+
+        /// <summary>
+        /// PDF: audio file already exists
+        /// </summary>
+        public static string GetCustomDirFilename(this AudioFileStorage _, LibraryBook libraryBook, string dirFullPath, string extension)
+            => Templates.File.GetFilename(libraryBook.ToDto(), dirFullPath, extension);
+    }
+}

FileLiberator/ConvertToMp3.cs

@@ -1,14 +1,14 @@
-using AAXClean;
+using System;
+using System.IO;
+using System.Threading.Tasks;
+using AAXClean;
+using AAXClean.Codecs;
 using DataLayer;
 using Dinah.Core;
 using Dinah.Core.ErrorHandling;
-using Dinah.Core.IO;
 using Dinah.Core.Net.Http;
 using FileManager;
-using System;
-using System.IO;
-using System.Linq;
-using System.Threading.Tasks;
+using LibationFileManager;
 
 namespace FileLiberator
 {
@@ -17,7 +17,7 @@ namespace FileLiberator
         private Mp4File m4bBook;
 
 		private long fileSize;
-		private static string Mp3FileName(string m4bPath) => m4bPath is null ? string.Empty : PathLib.ReplaceExtension(m4bPath, ".mp3");
+        private static string Mp3FileName(string m4bPath) => Path.ChangeExtension(m4bPath ?? "", ".mp3");
 
         public override void Cancel() => m4bBook?.Cancel();
 
@@ -52,9 +52,9 @@ namespace FileLiberator
                 m4bBook.InputStream.Close();
                 mp3File.Close();
 
-                var mp3Path = Mp3FileName(m4bPath);
-
-                FileExt.SafeMove(mp3File.Name, mp3Path);
+                var proposedMp3Path = Mp3FileName(m4bPath);
+                var realMp3Path = FileUtility.SaferMoveToValidPath(mp3File.Name, proposedMp3Path);
+                OnFileCreated(libraryBook, realMp3Path);
 
                 var statusHandler = new StatusHandler();
 
@@ -73,8 +73,8 @@ namespace FileLiberator
         private void M4bBook_ConversionProgressUpdate(object sender, ConversionProgressEventArgs e)
         {
             var duration = m4bBook.Duration;
-            double remainingSecsToProcess = (duration - e.ProcessPosition).TotalSeconds;
-            double estTimeRemaining = remainingSecsToProcess / e.ProcessSpeed;
+            var remainingSecsToProcess = (duration - e.ProcessPosition).TotalSeconds;
+            var estTimeRemaining = remainingSecsToProcess / e.ProcessSpeed;
 
             if (double.IsNormal(estTimeRemaining))
                 OnStreamingTimeRemaining(TimeSpan.FromSeconds(estTimeRemaining));

FileLiberator/DownloadDecryptBook.cs

@@ -9,6 +9,7 @@ using DataLayer;
 using Dinah.Core;
 using Dinah.Core.ErrorHandling;
 using FileManager;
+using LibationFileManager;
 
 namespace FileLiberator
 {
@@ -16,8 +17,27 @@ namespace FileLiberator
     {
         private AudiobookDownloadBase abDownloader;
 
+        public override bool Validate(LibraryBook libraryBook) => !libraryBook.Book.Audio_Exists;
+
+        public override void Cancel() => abDownloader?.Cancel();
+
         public override async Task<StatusHandler> ProcessAsync(LibraryBook libraryBook)
         {
+            var entries = new List<FilePathCache.CacheEntry>();
+            // these only work so minimally b/c CacheEntry is a record.
+            // in case of parallel decrypts, only capture the ones for this book id.
+            // if user somehow starts multiple decrypts of the same book in parallel: on their own head be it
+            void FilePathCache_Inserted(object sender, FilePathCache.CacheEntry e)
+            {
+                if (e.Id.EqualsInsensitive(libraryBook.Book.AudibleProductId))
+                    entries.Add(e);
+            }
+            void FilePathCache_Removed(object sender, FilePathCache.CacheEntry e)
+            {
+                if (e.Id.EqualsInsensitive(libraryBook.Book.AudibleProductId))
+                    entries.Remove(e);
+            }
+
             OnBegin(libraryBook);
 
             try
@@ -25,16 +45,29 @@ namespace FileLiberator
                 if (libraryBook.Book.Audio_Exists)
                     return new StatusHandler { "Cannot find decrypt. Final audio file already exists" };
 
-                var outputAudioFilename = await downloadAudiobookAsync(AudibleFileStorage.DownloadsInProgress, AudibleFileStorage.DecryptInProgress, libraryBook);
+                bool success = false;
+                try
+                {
+                    FilePathCache.Inserted += FilePathCache_Inserted;
+                    FilePathCache.Removed += FilePathCache_Removed;
+
+                    success = await downloadAudiobookAsync(libraryBook);
+                }
+                finally
+                {
+                    FilePathCache.Inserted -= FilePathCache_Inserted;
+                    FilePathCache.Removed -= FilePathCache_Removed;
+                }
 
                 // decrypt failed
-                if (outputAudioFilename is null)
+                if (!success)
                     return new StatusHandler { "Decrypt failed" };
 
-                // moves files and returns dest dir
-                var moveResults = MoveFilesToBooksDir(libraryBook.Book, outputAudioFilename);
+                // moves new files from temp dir to final dest
+                var movedAudioFile = moveFilesToBooksDir(libraryBook, entries);
 
-                if (!moveResults.movedAudioFile)
+                // decrypt failed
+                if (!movedAudioFile)
                     return new StatusHandler { "Cannot find final audio file after decryption" };
 
                 libraryBook.Book.UserDefinedItem.BookStatus = LiberatedStatus.Liberated;
@@ -47,13 +80,13 @@ namespace FileLiberator
             }
         }
 
-        private async Task<string> downloadAudiobookAsync(string cacheDir, string destinationDir, LibraryBook libraryBook)
+        private async Task<bool> downloadAudiobookAsync(LibraryBook libraryBook)
         {
             OnStreamingBegin($"Begin decrypting {libraryBook}");
 
             try
             {
-                validate(libraryBook);
+                downloadValidation(libraryBook);
 
                 var api = await libraryBook.GetApiAsync();
                 var contentLic = await api.GetDownloadLicenseAsync(libraryBook.Book.AudibleProductId);
@@ -81,28 +114,39 @@ namespace FileLiberator
                     foreach (var chap in contentLic.ContentMetadata?.ChapterInfo?.Chapters)
                         audiobookDlLic.ChapterInfo.AddChapter(chap.Title, TimeSpan.FromMilliseconds(chap.LengthMs));
                 }
-                
-                var outFileName = Path.Combine(destinationDir, $"{PathLib.ToPathSafeString(libraryBook.Book.Title)} [{libraryBook.Book.AudibleProductId}].{outputFormat.ToString().ToLower()}");
 
-                abDownloader = contentLic.DrmType == AudibleApi.Common.DrmType.Adrm
-                    ? new AaxcDownloadConverter(outFileName, cacheDir, audiobookDlLic, outputFormat, Configuration.Instance.SplitFilesByChapter)
-                    : new UnencryptedAudiobookDownloader(outFileName, cacheDir, audiobookDlLic);
-                abDownloader.AppName = "Libation";
-                abDownloader.DecryptProgressUpdate += (_, progress) => OnStreamingProgressChanged(progress);
-                abDownloader.DecryptTimeRemaining += (_, remaining) => OnStreamingTimeRemaining(remaining);
-                abDownloader.RetrievedTitle += (_, title) => OnTitleDiscovered(title);
-                abDownloader.RetrievedAuthors += (_, authors) => OnAuthorsDiscovered(authors);
-                abDownloader.RetrievedNarrators += (_, narrators) => OnNarratorsDiscovered(narrators);
+                var outFileName = AudibleFileStorage.Audio.GetInProgressFilename(libraryBook, outputFormat.ToString().ToLower());
+
+                var cacheDir = AudibleFileStorage.DownloadsInProgressDirectory;
+
+                if (contentLic.DrmType != AudibleApi.Common.DrmType.Adrm)
+                    abDownloader = new UnencryptedAudiobookDownloader(outFileName, cacheDir, audiobookDlLic);
+                else
+                {
+                    AaxcDownloadConvertBase converter
+                        = Configuration.Instance.SplitFilesByChapter ? new AaxcDownloadMultiConverter(
+                            outFileName, cacheDir, audiobookDlLic, outputFormat,
+                            AudibleFileStorage.Audio.CreateMultipartRenamerFunc(libraryBook))
+                        : new AaxcDownloadSingleConverter(outFileName, cacheDir, audiobookDlLic, outputFormat);
+
+                    if (Configuration.Instance.AllowLibationFixup)
+                        converter.RetrievedMetadata += (_, tags) => tags.Generes = string.Join(", ", libraryBook.Book.CategoriesNames);
+
+                    abDownloader = converter;
+                }
+
+                abDownloader.DecryptProgressUpdate += OnStreamingProgressChanged;
+                abDownloader.DecryptTimeRemaining += OnStreamingTimeRemaining;
+
+                abDownloader.RetrievedTitle += OnTitleDiscovered;
+                abDownloader.RetrievedAuthors += OnAuthorsDiscovered;
+                abDownloader.RetrievedNarrators += OnNarratorsDiscovered;
                 abDownloader.RetrievedCoverArt += AaxcDownloader_RetrievedCoverArt;
+                abDownloader.FileCreated += (_, path) => OnFileCreated(libraryBook, path);
 
                 // REAL WORK DONE HERE
                 var success = await Task.Run(abDownloader.Run);
-
-                // decrypt failed
-                if (!success)
-                    return null;
-
-                return outFileName;
+                return success;
             }
             finally
             {
@@ -110,76 +154,7 @@ namespace FileLiberator
             }
         }
 
-        private void AaxcDownloader_RetrievedCoverArt(object sender, byte[] e)
-        {
-            if (e is null && Configuration.Instance.AllowLibationFixup)
-            {
-                OnRequestCoverArt(abDownloader.SetCoverArt);
-            }
-
-            if (e is not null)
-            {
-                OnCoverImageDiscovered(e);
-            }
-        }
-
-        private static (string destinationDir, bool movedAudioFile) MoveFilesToBooksDir(Book product, string outputAudioFilename)
-        {
-            // create final directory. move each file into it. MOVE AUDIO FILE LAST
-            // new dir: safetitle_limit50char + " [" + productId + "]"
-            // TODO make this method handle multiple audio files or a single audio file.
-            var destinationDir = AudibleFileStorage.Audio.GetDestDir(product.Title, product.AudibleProductId);
-            Directory.CreateDirectory(destinationDir);
-
-            var sortedFiles = getProductFilesSorted(product, outputAudioFilename);
-
-            var musicFileExt = Path.GetExtension(outputAudioFilename).Trim('.');
-
-            // audio filename: safetitle_limit50char + " [" + productId + "]." + audio_ext
-            var audioFileName = FileUtility.GetValidFilename(destinationDir, product.Title, musicFileExt, product.AudibleProductId);
-
-            bool movedAudioFile = false;
-            foreach (var f in sortedFiles)
-            {
-                var dest
-                    = AudibleFileStorage.Audio.IsFileTypeMatch(f)//f.Extension.Equals($".{musicFileExt}", StringComparison.OrdinalIgnoreCase)
-                    ? Path.Join(destinationDir, f.Name)
-                    // non-audio filename: safetitle_limit50char + " [" + productId + "][" + audio_ext + "]." + non_audio_ext
-                    : FileUtility.GetValidFilename(destinationDir, product.Title, f.Extension, product.AudibleProductId, musicFileExt);
-
-                if (Path.GetExtension(dest).Trim('.').ToLower() == "cue")
-                    Cue.UpdateFileName(f, audioFileName);
-
-                File.Move(f.FullName, dest);
-
-                movedAudioFile |= AudibleFileStorage.Audio.IsFileTypeMatch(f);
-            }
-
-            AudibleFileStorage.Audio.Refresh();
-
-            return (destinationDir, movedAudioFile);
-        }
-
-        private static List<FileInfo> getProductFilesSorted(Book product, string outputAudioFilename)
-        {
-            // files are: temp path\author\[asin].ext
-            var m4bDir = new FileInfo(outputAudioFilename).Directory;
-            var files = m4bDir
-                .EnumerateFiles()
-                .Where(f => f.Name.ContainsInsensitive(product.AudibleProductId))
-                .ToList();
-
-            // move audio files to the end of the collection so these files are moved last
-            var musicFiles = files.Where(f => AudibleFileStorage.Audio.IsFileTypeMatch(f));
-            var sortedFiles = files
-                .Except(musicFiles)
-                .Concat(musicFiles)
-                .ToList();
-
-            return sortedFiles;
-        }
-
-        private static void validate(LibraryBook libraryBook)
+        private static void downloadValidation(LibraryBook libraryBook)
         {
             string errorString(string field)
                 => $"{errorTitle()}\r\nCannot download book. {field} is not known. Try re-importing the account which owns this book.";
@@ -201,11 +176,45 @@ namespace FileLiberator
                 throw new Exception(errorString("Locale"));
         }
 
-        public override bool Validate(LibraryBook libraryBook) => !libraryBook.Book.Audio_Exists;
-
-        public override void Cancel()
+        private void AaxcDownloader_RetrievedCoverArt(object _, byte[] e)
         {
-            abDownloader?.Cancel();
+            if (e is not null)
+                OnCoverImageDiscovered(e);
+            else if (Configuration.Instance.AllowLibationFixup)
+                OnRequestCoverArt(abDownloader.SetCoverArt);
         }
-    }
+
+        /// <summary>Move new files to 'Books' directory</summary>
+        /// <returns>True if audiobook file(s) were successfully created and can be located on disk. Else false.</returns>
+        private static bool moveFilesToBooksDir(LibraryBook libraryBook, List<FilePathCache.CacheEntry> entries)
+        {
+            // create final directory. move each file into it
+            var destinationDir = AudibleFileStorage.Audio.GetDestinationDirectory(libraryBook);
+            Directory.CreateDirectory(destinationDir);
+
+            FilePathCache.CacheEntry getFirstAudio() => entries.FirstOrDefault(f => f.FileType == FileType.Audio);
+
+			if (getFirstAudio() == default)
+				return false;
+
+			for (var i = 0; i < entries.Count; i++)
+			{
+				var entry = entries[i];
+
+				var realDest = FileUtility.SaferMoveToValidPath(entry.Path, Path.Combine(destinationDir, Path.GetFileName(entry.Path)));
+				FilePathCache.Insert(libraryBook.Book.AudibleProductId, realDest);
+
+				// propogate corrected path. Must update cache with corrected path. Also want updated path for cue file (after this for-loop)
+				entries[i] = entry with { Path = realDest };
+			}
+
+			var cue = entries.FirstOrDefault(f => f.FileType == FileType.Cue);
+			if (cue != default)
+				Cue.UpdateFileName(cue.Path, getFirstAudio().Path);
+
+			AudibleFileStorage.Audio.Refresh();
+
+			return true;
+		}
+	}
 }

FileLiberator/DownloadFile.cs

@@ -12,14 +12,14 @@ namespace FileLiberator
 		{
 			var client = new HttpClient();
 
-			var progress = new Progress<DownloadProgress>();
-			progress.ProgressChanged += (_, e) => OnStreamingProgressChanged(e);
+			var progress = new Progress<DownloadProgress>(OnStreamingProgressChanged);
 
 			OnStreamingBegin(proposedDownloadFilePath);
 
 			try
 			{
 				var actualDownloadedFilePath = await client.DownloadFileAsync(downloadUrl, proposedDownloadFilePath, progress);
+				OnFileCreated("Upgrade", actualDownloadedFilePath);
 				return actualDownloadedFilePath;
 			}
 			finally

FileLiberator/DownloadPdf.cs

@@ -8,6 +8,7 @@ using DataLayer;
 using Dinah.Core.ErrorHandling;
 using Dinah.Core.Net.Http;
 using FileManager;
+using LibationFileManager;
 
 namespace FileLiberator
 {
@@ -39,19 +40,14 @@ namespace FileLiberator
 
 		private static string getProposedDownloadFilePath(LibraryBook libraryBook)
 		{
+			var extension = Path.GetExtension(getdownloadUrl(libraryBook));
+
 			// if audio file exists, get it's dir. else return base Book dir
 			var existingPath = Path.GetDirectoryName(AudibleFileStorage.Audio.GetPath(libraryBook.Book.AudibleProductId));
-			var file = getdownloadUrl(libraryBook);
+			if (existingPath is not null)
+				return AudibleFileStorage.Audio.GetCustomDirFilename(libraryBook, existingPath, extension);
 
-			if (existingPath != null)
-				return Path.Combine(existingPath, Path.GetFileName(file));
-
-			var full = FileUtility.GetValidFilename(
-				AudibleFileStorage.PdfStorageDirectory,
-				libraryBook.Book.Title,
-				Path.GetExtension(file),
-				libraryBook.Book.AudibleProductId);
-			return full;
+			return AudibleFileStorage.Audio.GetBooksDirectoryFilename(libraryBook, extension);
 		}
 
 		private static string getdownloadUrl(LibraryBook libraryBook)
@@ -66,12 +62,13 @@ namespace FileLiberator
 				var api = await libraryBook.GetApiAsync();
 				var downloadUrl = await api.GetPdfDownloadLinkAsync(libraryBook.Book.AudibleProductId);
 
-				var progress = new Progress<DownloadProgress>();
-				progress.ProgressChanged += (_, e) => OnStreamingProgressChanged(e);
+				var progress = new Progress<DownloadProgress>(OnStreamingProgressChanged);
 
 				var client = new HttpClient();
 
 				var actualDownloadedFilePath = await client.DownloadFileAsync(downloadUrl, proposedDownloadFilePath, progress);
+				OnFileCreated(libraryBook, actualDownloadedFilePath);
+
 				OnStatusUpdate(actualDownloadedFilePath);
 				return actualDownloadedFilePath;
 			}

FileLiberator/FileLiberator.csproj

@@ -1,14 +1,13 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
     <ProjectReference Include="..\AaxDecrypter\AaxDecrypter.csproj" />
     <ProjectReference Include="..\DataLayer\DataLayer.csproj" />
-    <ProjectReference Include="..\FileManager\FileManager.csproj" />
-    <ProjectReference Include="..\InternalUtilities\InternalUtilities.csproj" />
+    <ProjectReference Include="..\AudibleUtilities\AudibleUtilities.csproj" />
   </ItemGroup>
 
 </Project>

FileLiberator/Processable.cs

@@ -27,7 +27,7 @@ namespace FileLiberator
         public IEnumerable<LibraryBook> GetValidLibraryBooks(IEnumerable<LibraryBook> library)
             => library.Where(libraryBook =>
                 Validate(libraryBook)
-                && (libraryBook.Book.ContentType != ContentType.Episode || FileManager.Configuration.Instance.DownloadEpisodes)
+                && (libraryBook.Book.ContentType != ContentType.Episode || LibationFileManager.Configuration.Instance.DownloadEpisodes)
                 );
 
         public async Task<StatusHandler> ProcessSingleAsync(LibraryBook libraryBook, bool validate)

FileLiberator/Streamable.cs

@@ -9,6 +9,8 @@ namespace FileLiberator
         public event EventHandler<DownloadProgress> StreamingProgressChanged;
         public event EventHandler<TimeSpan> StreamingTimeRemaining;
         public event EventHandler<string> StreamingCompleted;
+        /// <summary>Fired when a file is successfully saved to disk</summary>
+        public event EventHandler<(string id, string path)> FileCreated;
 
         protected void OnStreamingBegin(string filePath)
         {
@@ -16,12 +18,14 @@ namespace FileLiberator
             StreamingBegin?.Invoke(this, filePath);
         }
 
-        protected void OnStreamingProgressChanged(DownloadProgress progress)
+        protected void OnStreamingProgressChanged(DownloadProgress progress) => OnStreamingProgressChanged(null, progress);
+        protected void OnStreamingProgressChanged(object _, DownloadProgress progress)
         {
             StreamingProgressChanged?.Invoke(this, progress);
         }
 
-        protected void OnStreamingTimeRemaining(TimeSpan timeRemaining)
+        protected void OnStreamingTimeRemaining(TimeSpan timeRemaining) => OnStreamingTimeRemaining(null, timeRemaining);
+        protected void OnStreamingTimeRemaining(object _, TimeSpan timeRemaining)
         {
             StreamingTimeRemaining?.Invoke(this, timeRemaining);
         }
@@ -30,8 +34,14 @@ namespace FileLiberator
         {
             Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(StreamingCompleted), Message = filePath });
             StreamingCompleted?.Invoke(this, filePath);
+        }
 
-            //TODO: Update file cache
+        protected void OnFileCreated(DataLayer.LibraryBook libraryBook, string path) => OnFileCreated(libraryBook.Book.AudibleProductId, path);
+        protected void OnFileCreated(string id, string path)
+        {
+            Serilog.Log.Logger.Information("File created {@DebugInfo}", new { Name = nameof(FileCreated), id, path });
+            LibationFileManager.FilePathCache.Insert(id, path);
+            FileCreated?.Invoke(this, (id, path));
         }
     }
 }

FileLiberator/UtilityExtensions.cs

@@ -4,6 +4,7 @@ using System.Linq;
 using System.Threading.Tasks;
 using DataLayer;
 using Dinah.Core;
+using LibationFileManager;
 
 namespace FileLiberator
 {
@@ -19,8 +20,24 @@ namespace FileLiberator
 
 		public static async Task<AudibleApi.Api> GetApiAsync(this LibraryBook libraryBook)
 		{
-			var apiExtended = await InternalUtilities.ApiExtended.CreateAsync(libraryBook.Account, libraryBook.Book.Locale);
+			var apiExtended = await AudibleUtilities.ApiExtended.CreateAsync(libraryBook.Account, libraryBook.Book.Locale);
 			return apiExtended.Api;
 		}
+
+		public static LibraryBookDto ToDto(this LibraryBook libraryBook) => new()
+		{
+			Account = libraryBook.Account,
+
+			AudibleProductId = libraryBook.Book.AudibleProductId,
+			Title = libraryBook.Book.Title ?? "",
+			Locale = libraryBook.Book.Locale,
+
+			Authors = libraryBook.Book.Authors.Select(c => c.Name).ToList(),
+
+			Narrators = libraryBook.Book.Narrators.Select(c => c.Name).ToList(),
+
+			SeriesName = libraryBook.Book.SeriesLink.FirstOrDefault()?.Series.Name,
+			SeriesNumber = libraryBook.Book.SeriesLink.FirstOrDefault()?.Order
+		};
 	}
 }

FileLiberator/_InternalsVisible.cs

@@ -0,0 +1 @@
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo(nameof(FileLiberator) + ".Tests")]

FileManager/AudibleFileStorage.cs

@@ -1,149 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text.RegularExpressions;
-using Dinah.Core;
-using Dinah.Core.Collections.Generic;
-
-namespace FileManager
-{
-    public enum FileType { Unknown, Audio, AAXC, PDF }
-
-	public abstract class AudibleFileStorage : Enumeration<AudibleFileStorage>
-	{
-		protected abstract string[] Extensions { get; }
-		public abstract string StorageDirectory { get; }
-
-		public static string DownloadsInProgress => Directory.CreateDirectory(Path.Combine(Configuration.Instance.InProgress, "DownloadsInProgress")).FullName;
-        public static string DecryptInProgress => Directory.CreateDirectory(Path.Combine(Configuration.Instance.InProgress, "DecryptInProgress")).FullName;
-
-        public static string PdfStorageDirectory => BooksDirectory;
-
-		private static AaxcFileStorage AAXC { get; } = new AaxcFileStorage();
-        public static bool AaxcExists(string productId) => AAXC.Exists(productId);
-
-		#region static
-		public static AudioFileStorage Audio { get; } = new AudioFileStorage();
-
-        public static string BooksDirectory
-        {
-            get
-            {
-                if (string.IsNullOrWhiteSpace(Configuration.Instance.Books))
-                    Configuration.Instance.Books = Path.Combine(Configuration.UserProfile, "Books");
-                return Directory.CreateDirectory(Configuration.Instance.Books).FullName;
-            }
-        }
-
-        private static object bookDirectoryFilesLocker { get; } = new();
-        internal static BackgroundFileSystem BookDirectoryFiles { get; set; }
-        #endregion
-
-        #region instance
-        public FileType FileType => (FileType)Value;
-
-		protected IEnumerable<string> extensions_noDots { get; }
-        private string extAggr { get; }
-
-        protected AudibleFileStorage(FileType fileType) : base((int)fileType, fileType.ToString())
-		{
-			extensions_noDots = Extensions.Select(ext => ext.ToLower().Trim('.')).ToList();
-			extAggr = extensions_noDots.Aggregate((a, b) => $"{a}|{b}");
-            BookDirectoryFiles ??= new BackgroundFileSystem(BooksDirectory, "*.*", SearchOption.AllDirectories);
-        }
-
-        protected string GetFilePath(string productId)
-        {
-            var cachedFile = FilePathCache.GetPath(productId, FileType);
-            if (cachedFile != null)
-                return cachedFile;
-
-            var regex = new Regex($@"{productId}.*?\.({extAggr})$", RegexOptions.IgnoreCase);
-
-            string firstOrNull;
-
-            if (StorageDirectory == BooksDirectory)
-            {
-                //If user changed the BooksDirectory, reinitialize.
-                if (StorageDirectory != BookDirectoryFiles.RootDirectory)
-				{
-                    lock (bookDirectoryFilesLocker)
-                    {
-                        if (StorageDirectory != BookDirectoryFiles.RootDirectory)
-                        {
-                            BookDirectoryFiles = new BackgroundFileSystem(StorageDirectory, "*.*", SearchOption.AllDirectories);
-                        }
-                    }
-				}
-
-                firstOrNull = BookDirectoryFiles.FindFile(regex);
-            }
-            else
-            {
-                firstOrNull =
-                    Directory
-                    .EnumerateFiles(StorageDirectory, "*.*", SearchOption.AllDirectories)
-                    .FirstOrDefault(s => regex.IsMatch(s));
-            }
-
-			if (firstOrNull is null)
-				return null;
-
-			FilePathCache.Upsert(productId, FileType, firstOrNull);
-			return firstOrNull;
-        }
-        #endregion
-    }
-
-    public class AudioFileStorage : AudibleFileStorage
-    {
-        protected override string[] Extensions { get; } = new[] { "m4b", "mp3", "aac", "mp4", "m4a", "ogg", "flac" };
-
-        // we always want to use the latest config value, therefore
-        // - DO use 'get' arrow "=>"
-        // - do NOT use assign "="
-        public override string StorageDirectory => BooksDirectory;
-
-        public AudioFileStorage() : base(FileType.Audio) { }
-
-        public void Refresh() => BookDirectoryFiles.RefreshFiles();
-
-        public string GetDestDir(string title, string asin)
-        {
-            // to prevent the paths from getting too long, we don't need after the 1st ":" for the folder
-            var underscoreIndex = title.IndexOf(':');
-            var titleDir
-                = underscoreIndex < 4
-                ? title
-                : title.Substring(0, underscoreIndex);
-            var finalDir = FileUtility.GetValidFilename(StorageDirectory, titleDir, null, asin);
-            return finalDir;
-        }
-
-        public bool IsFileTypeMatch(FileInfo fileInfo)
-            => extensions_noDots.ContainsInsensative(fileInfo.Extension.Trim('.'));
-
-        public string GetPath(string productId) => GetFilePath(productId);
-    }
-
-    public class AaxcFileStorage : AudibleFileStorage
-    {
-        protected override string[] Extensions { get; } = new[] { "aaxc" };
-
-        // we always want to use the latest config value, therefore
-        // - DO use 'get' arrow "=>"
-        // - do NOT use assign "="
-        public override string StorageDirectory => DownloadsInProgress;
-
-        public AaxcFileStorage() : base(FileType.AAXC) { }
-
-        /// <summary>
-        /// Example for full books:
-        /// Search recursively in _books directory. Full book exists if either are true
-        /// - a directory name has the product id and an audio file is immediately inside
-        /// - any audio filename contains the product id
-        /// </summary>
-        public bool Exists(string productId) => GetFilePath(productId) != null;
-    }
-}

FileManager/BackgroundFileSystem.cs

@@ -8,13 +8,9 @@ using System.Threading.Tasks;
 namespace FileManager
 {
     /// <summary>
-    /// Tracks actual locations of files. This is especially useful for clicking button to navigate to the book's files.
-    /// 
-    /// Note: this is no longer how Libation manages "Liberated" state. That is not statefully managed in the database.
-    /// This paradigm is what allows users to manually choose to not download books. Also allows them to manually toggle
-    /// this state and download again.
+    /// Tracks actual locations of files.
     /// </summary>
-    internal class BackgroundFileSystem
+    public class BackgroundFileSystem
     {
         public string RootDirectory { get; private set; }
         public string SearchPattern { get; private set; }
@@ -47,7 +43,7 @@ namespace FileManager
             lock (fsCacheLocker)
             {
                 fsCache.Clear();
-                fsCache.AddRange(Directory.EnumerateFiles(RootDirectory, SearchPattern, SearchOption));
+                fsCache.AddRange(FileUtility.SaferEnumerateFiles(RootDirectory, SearchPattern, SearchOption));
             }
         }
 
@@ -56,7 +52,7 @@ namespace FileManager
             Stop();
 
             lock (fsCacheLocker)
-                fsCache.AddRange(Directory.EnumerateFiles(RootDirectory, SearchPattern, SearchOption));
+                fsCache.AddRange(FileUtility.SaferEnumerateFiles(RootDirectory, SearchPattern, SearchOption));
 
             directoryChangesEvents = new BlockingCollection<FileSystemEventArgs>();
 			fileSystemWatcher = new FileSystemWatcher(RootDirectory)
@@ -139,7 +135,7 @@ namespace FileManager
         private void AddPath(string path)
         {
             if (File.GetAttributes(path).HasFlag(FileAttributes.Directory))
-                AddUniqueFiles(Directory.EnumerateFiles(path, SearchPattern, SearchOption));
+                AddUniqueFiles(FileUtility.SaferEnumerateFiles(path, SearchPattern, SearchOption));
             else
                 AddUniqueFile(path);
         }

FileManager/FileManager.csproj

@@ -1,13 +1,12 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Dinah.Core" Version="1.1.1.2" />
-    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="5.0.0" />
-    <PackageReference Include="Polly" Version="7.2.2" />
+    <PackageReference Include="Dinah.Core" Version="4.0.6.1" />
+    <PackageReference Include="Polly" Version="7.2.3" />
   </ItemGroup>
 
 </Project>

FileManager/FileNamingTemplate.cs

@@ -0,0 +1,64 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Dinah.Core;
+
+namespace FileManager
+{
+    /// <summary>Get valid filename. Advanced features incl. parameterized template</summary>
+    public class FileNamingTemplate
+    {
+        /// <summary>Proposed full file path. May contain optional html-styled template tags. Eg: &lt;name&gt;</summary>
+        public string Template { get; }
+
+        /// <param name="template">Proposed file name with optional html-styled template tags.</param>
+        public FileNamingTemplate(string template) => Template = ArgumentValidator.EnsureNotNullOrWhiteSpace(template, nameof(template));
+
+        /// <summary>Optional step 1: Replace html-styled template tags with parameters. Eg {"name", "Bill Gates"} => /&lt;name&gt;/ => /Bill Gates/</summary>
+        public Dictionary<string, object> ParameterReplacements { get; } = new Dictionary<string, object>();
+
+        /// <summary>Convenience method</summary>
+        public void AddParameterReplacement(string key, object value)
+            // using .Add() instead of "[key] = value" will make unintended overwriting throw exception
+            => ParameterReplacements.Add(key, value);
+
+        /// <summary>If set, truncate each parameter replacement to this many characters. Default 50</summary>
+        public int? ParameterMaxSize { get; set; } = 50;
+
+        /// <summary>Optional step 2: Replace all illegal characters with this. Default=<see cref="string.Empty"/></summary>
+        public string IllegalCharacterReplacements { get; set; }
+
+        /// <summary>Generate a valid path for this file or directory</summary>
+        public string GetFilePath()
+        {
+            var filename = Template;
+
+            foreach (var r in ParameterReplacements)
+                filename = filename.Replace($"<{formatKey(r.Key)}>", formatValue(r.Value));
+
+            return FileUtility.GetValidFilename(filename, IllegalCharacterReplacements);
+        }
+
+        private static string formatKey(string key)
+            => key
+            .Replace("<", "")
+            .Replace(">", "");
+
+        private string formatValue(object value)
+        {
+            if (value is null)
+                return "";
+
+            // Other illegal characters will be taken care of later. Must take care of slashes now so params can't introduce new folders.
+            // Esp important for file templates.
+            var val = value
+                .ToString()
+                .Replace($"{System.IO.Path.DirectorySeparatorChar}", IllegalCharacterReplacements)
+                .Replace($"{System.IO.Path.AltDirectorySeparatorChar}", IllegalCharacterReplacements);
+            return 
+                ParameterMaxSize.HasValue && ParameterMaxSize.Value > 0
+                ? val.Truncate(ParameterMaxSize.Value)
+                : val;
+        }
+    }
+}

FileManager/FilePathCache.cs

@@ -1,95 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using Dinah.Core.Collections.Immutable;
-using Newtonsoft.Json;
-
-namespace FileManager
-{
-	public static class FilePathCache
-    {
-		private const string FILENAME = "FileLocations.json";
-        internal class CacheEntry
-        {
-            public string Id { get; set; }
-            public FileType FileType { get; set; }
-            public string Path { get; set; }
-        }
-
-		private static Cache<CacheEntry> cache { get; } = new Cache<CacheEntry>();
-
-		private static string jsonFile => Path.Combine(Configuration.Instance.LibationFiles, FILENAME);
-
-        static FilePathCache()
-        {
-			// load json into memory. if file doesn't exist, nothing to do. save() will create if needed
-			if (File.Exists(jsonFile))
-			{
-				var list = JsonConvert.DeserializeObject<List<CacheEntry>>(File.ReadAllText(jsonFile));
-				cache = new Cache<CacheEntry>(list);
-			}
-        }
-
-        public static bool Exists(string id, FileType type) => GetPath(id, type) != null;
-
-        public static string GetPath(string id, FileType type)
-        {
-            var entry = cache.SingleOrDefault(i => i.Id == id && i.FileType == type);
-
-            if (entry == null)
-                return null;
-
-            if (!File.Exists(entry.Path))
-            {
-                remove(entry);
-                return null;
-            }
-
-            return entry.Path;
-        }
-
-        private static void remove(CacheEntry entry)
-		{
-			cache.Remove(entry);
-			save();
-		}
-
-        public static void Upsert(string id, FileType type, string path)
-        {
-            if (!File.Exists(path))
-                throw new FileNotFoundException("Cannot add path to cache. File not found");
-
-			var entry = cache.SingleOrDefault(i => i.Id == id && i.FileType == type);
-
-			if (entry is null)
-				cache.Add(new CacheEntry { Id = id, FileType = type, Path = path });
-			else
-				entry.Path = path;
-
-			save();
-		}
-
-		// cache is thread-safe and lock free. but file saving is not
-		private static object locker { get; } = new object();
-		private static void save()
-		{
-			// create json if not exists
-			static void resave() => File.WriteAllText(jsonFile, JsonConvert.SerializeObject(cache.ToList(), Formatting.Indented));
-
-			lock (locker)
-			{
-				try { resave(); }
-				catch (IOException)
-				{
-					try { resave(); }
-					catch (IOException ex)
-					{
-						Serilog.Log.Logger.Error(ex, $"Error saving {FILENAME}");
-						throw;
-					}
-				}
-			}
-        }
-    }
-}

FileManager/FileUtility.cs

@@ -1,52 +1,272 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+using Dinah.Core;
+using Polly;
+using Polly.Retry;
 
 namespace FileManager
 {
     public static class FileUtility
     {
-        public static string GetValidFilename(string dirFullPath, string filename, string extension, params string[] metadataSuffixes)
+        /// <summary>
+        /// "txt" => ".txt"
+        /// <br />".txt" => ".txt"
+        /// <br />null or whitespace => ""
+        /// </summary>
+        public static string GetStandardizedExtension(string extension)
+            => string.IsNullOrWhiteSpace(extension)
+            ? (extension ?? "")?.Trim()
+            : '.' + extension.Trim().Trim('.');
+
+        /// <summary>
+        /// Return position with correct number of leading zeros.
+        /// <br />- 2 of 9 => "2"
+        /// <br />- 2 of 90 => "02"
+        /// <br />- 2 of 900 => "002"
+        /// </summary>
+        /// <param name="position">position in sequence. The 'x' in 'x of y'</param>
+        /// <param name="total">total qty in sequence. The 'y' in 'x of y'</param>
+        public static string GetSequenceFormatted(int position, int total)
         {
-            if (string.IsNullOrWhiteSpace(dirFullPath))
-                throw new ArgumentException($"{nameof(dirFullPath)} may not be null or whitespace", nameof(dirFullPath));
+            ArgumentValidator.EnsureGreaterThan(position, nameof(position), 0);
+            ArgumentValidator.EnsureGreaterThan(total, nameof(total), 0);
+            if (position > total)
+                throw new ArgumentException($"{position} may not be greater than {total}");
 
-            // file max length = 255. dir max len = 247
+            return position.ToString().PadLeft(total.ToString().Length, '0');
+        }
 
-            // sanitize
-            filename = getAsciiTag(filename);
-            // manage length
-            if (filename.Length > 50)
-                filename = filename.Substring(0, 50) + "[...]";
+        private const int MAX_FILENAME_LENGTH = 255;
+        private const int MAX_DIRECTORY_LENGTH = 247;
 
-            // append id. it is 10 or 14 char in the common cases
-            if (metadataSuffixes != null && metadataSuffixes.Length > 0)
-                filename += " [" + string.Join("][", metadataSuffixes) + "]";
+        /// <summary>
+        /// Ensure valid file name path: 
+        /// <br/>- remove invalid chars
+        /// <br/>- ensure uniqueness
+        /// <br/>- enforce max file length
+        /// </summary>
+        public static string GetValidFilename(string path, string illegalCharacterReplacements = "")
+        {
+            ArgumentValidator.EnsureNotNull(path, nameof(path));
 
-            // this method may also be used for directory names, so no guarantee of extension
-            if (!string.IsNullOrWhiteSpace(extension))
-                extension = '.' + extension.Trim('.');
+            // remove invalid chars
+            path = GetSafePath(path, illegalCharacterReplacements);
+
+            // ensure uniqueness and check lengths
+            var dir = Path.GetDirectoryName(path);
+            dir = dir.Truncate(MAX_DIRECTORY_LENGTH);
+
+            var filename = Path.GetFileNameWithoutExtension(path);
+            var fileStem = Path.Combine(dir, filename);
+
+            var extension = Path.GetExtension(path);
+
+            var fullfilename = fileStem.Truncate(MAX_FILENAME_LENGTH - extension.Length) + extension;
+
+            fullfilename = removeInvalidWhitespace(fullfilename);
 
-            // ensure uniqueness
-            var fullfilename = Path.Combine(dirFullPath, filename + extension);
             var i = 0;
             while (File.Exists(fullfilename))
-                fullfilename = Path.Combine(dirFullPath, filename + $" ({++i})" + extension);
+            {
+                var increm = $" ({++i})";
+                fullfilename = fileStem.Truncate(MAX_FILENAME_LENGTH - increm.Length - extension.Length) + increm + extension;
+            }
 
             return fullfilename;
         }
 
-        private static string getAsciiTag(string property)
+        // GetInvalidFileNameChars contains everything in GetInvalidPathChars plus ':', '*', '?', '\\', '/'
+
+        /// <summary>Use with file name, not full path. Valid path charaters which are invalid file name characters will be replaced: ':', '\\', '/'</summary>
+        public static string GetSafeFileName(string str, string illegalCharacterReplacements = "")
+            => string.Join(illegalCharacterReplacements ?? "", str.Split(Path.GetInvalidFileNameChars()));
+
+        /// <summary>Use with full path, not file name. Valid path charaters which are invalid file name characters will be retained: '\\', '/'</summary>
+        public static string GetSafePath(string path, string illegalCharacterReplacements = "")
         {
-            if (property == null)
-                return "";
+            ArgumentValidator.EnsureNotNull(path, nameof(path));
 
-            // omit characters which are invalid. EXCEPTION: change colon to underscore
-            property = property.Replace(':', '_');
+            path = replaceInvalidChars(path, illegalCharacterReplacements);
+            path = standardizeSlashes(path);
+            path = replaceColons(path, illegalCharacterReplacements);
+            path = removeDoubleSlashes(path);
 
-            // GetInvalidFileNameChars contains everything in GetInvalidPathChars plus ':', '*', '?', '\\', '/'
-            foreach (var ch in Path.GetInvalidFileNameChars())
-                property = property.Replace(ch.ToString(), "");
-            return property;
+            return path;
+        }
+
+        private static char[] invalidChars { get; } = Path.GetInvalidPathChars().Union(new[] {
+                '*', '?',
+                // these are weird. If you run Path.GetInvalidPathChars() in Visual Studio's "C# Interactive", then these characters are included.
+                // In live code, Path.GetInvalidPathChars() does not include them
+                '"', '<', '>'
+            }).ToArray();
+        private static string replaceInvalidChars(string path, string illegalCharacterReplacements)
+            => string.Join(illegalCharacterReplacements ?? "", path.Split(invalidChars));
+
+        private static string standardizeSlashes(string path)
+            => path.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar);
+
+        private static string replaceColons(string path, string illegalCharacterReplacements)
+        {
+            // replace all colons except within the first 2 chars
+            var builder = new System.Text.StringBuilder();
+            for (var i = 0; i < path.Length; i++)
+            {
+                var c = path[i];
+                if (i >= 2 && c == ':')
+                    builder.Append(illegalCharacterReplacements);
+                else
+                    builder.Append(c);
+            }
+            return builder.ToString();
+        }
+
+        private static string removeDoubleSlashes(string path)
+        {
+            if (path.Length < 2)
+                return path;
+
+            // exception: don't try to condense the initial dbl bk slashes in a path. eg: \\192.168.0.1
+
+            var remainder = path[1..];
+            var dblSeparator = $"{Path.DirectorySeparatorChar}{Path.DirectorySeparatorChar}";
+            while (remainder.Contains(dblSeparator))
+                remainder = remainder.Replace(dblSeparator, $"{Path.DirectorySeparatorChar}");
+
+            return path[0] + remainder;
+        }
+
+        private static string removeInvalidWhitespace_pattern { get; } = $@"[\s\.]*\{Path.DirectorySeparatorChar}\s*";
+        private static Regex removeInvalidWhitespace_regex { get; } = new(removeInvalidWhitespace_pattern, RegexOptions.Compiled | RegexOptions.IgnorePatternWhitespace);
+
+        /// <summary>no part of the path may begin or end in whitespace</summary>
+        private static string removeInvalidWhitespace(string fullfilename)
+        {
+            // no whitespace at beginning or end
+            // replace whitespace around path slashes
+            //    regex (with space added for clarity)
+            //    \s*  \\  \s*    =>    \
+            // no ending dots. beginning dots are valid
+
+            // regex is easier by ending with separator
+            fullfilename += Path.DirectorySeparatorChar;
+            fullfilename = removeInvalidWhitespace_regex.Replace(fullfilename, Path.DirectorySeparatorChar.ToString());
+            // take seperator back off
+            fullfilename = RemoveLastCharacter(fullfilename);
+
+            fullfilename = removeDoubleSlashes(fullfilename);
+            return fullfilename;
+        }
+
+        public static string RemoveLastCharacter(this string str) => string.IsNullOrEmpty(str) ? str : str[..^1];
+
+        /// <summary>
+        /// Move file.
+        /// <br/>- Ensure valid file name path: remove invalid chars, ensure uniqueness, enforce max file length
+        /// <br/>- Perform <see cref="SaferMove"/>
+        /// <br/>- Return valid path
+        /// </summary>
+        public static string SaferMoveToValidPath(string source, string destination)
+        {
+            destination = GetValidFilename(destination);
+            SaferMove(source, destination);
+            return destination;
+        }
+
+        private static int maxRetryAttempts { get; } = 3;
+        private static TimeSpan pauseBetweenFailures { get; } = TimeSpan.FromMilliseconds(100);
+        private static RetryPolicy retryPolicy { get; } =
+            Policy
+            .Handle<Exception>()
+            .WaitAndRetry(maxRetryAttempts, i => pauseBetweenFailures);
+
+        /// <summary>Delete file. No error when source does not exist. Retry up to 3 times before throwing exception.</summary>
+        public static void SaferDelete(string source)
+            => retryPolicy.Execute(() =>
+            {
+                try
+                {
+                    if (!File.Exists(source))
+                    {
+                        Serilog.Log.Logger.Debug("No file to delete: {@DebugText}", new { source });
+                        return;
+                    }
+
+                    Serilog.Log.Logger.Debug("Attempt to delete file: {@DebugText}", new { source });
+                    File.Delete(source);
+                    Serilog.Log.Logger.Information("File successfully deleted: {@DebugText}", new { source });
+                }
+                catch (Exception e)
+                {
+                    Serilog.Log.Logger.Error(e, "Failed to delete file: {@DebugText}", new { source });
+                    throw;
+                }
+            });
+
+        /// <summary>Move file. No error when source does not exist. Retry up to 3 times before throwing exception.</summary>
+		public static void SaferMove(string source, string destination)
+            => retryPolicy.Execute(() =>
+            {
+                try
+                {
+                    if (!File.Exists(source))
+                    {
+                        Serilog.Log.Logger.Debug("No file to move: {@DebugText}", new { source });
+                        return;
+                    }
+
+                    SaferDelete(destination);
+
+                    var dir = Path.GetDirectoryName(destination);
+                    Serilog.Log.Logger.Debug("Attempt to create directory: {@DebugText}", new { dir });
+                    Directory.CreateDirectory(dir);
+
+                    Serilog.Log.Logger.Debug("Attempt to move file: {@DebugText}", new { source, destination });
+                    File.Move(source, destination);
+                    Serilog.Log.Logger.Information("File successfully moved: {@DebugText}", new { source, destination });
+                }
+                catch (Exception e)
+                {
+                    Serilog.Log.Logger.Error(e, "Failed to move file: {@DebugText}", new { source, destination });
+                    throw;
+                }
+            });
+
+        /// <summary>
+        /// A safer way to get all the files in a directory and sub directory without crashing on UnauthorizedException or PathTooLongException
+        /// </summary>
+        /// <param name="rootPath">Starting directory</param>
+        /// <param name="patternMatch">Filename pattern match</param>
+        /// <param name="searchOption">Search subdirectories or only top level directory for files</param>
+        /// <returns>List of files</returns>
+        public static IEnumerable<string> SaferEnumerateFiles(string path, string searchPattern = "*", SearchOption searchOption = SearchOption.TopDirectoryOnly)
+        {
+            var foundFiles = Enumerable.Empty<string>();
+
+            if (searchOption == SearchOption.AllDirectories)
+            {
+                try
+                {
+                    IEnumerable<string> subDirs = Directory.EnumerateDirectories(path);
+                    // Add files in subdirectories recursively to the list
+                    foreach (string dir in subDirs)
+                        foundFiles = foundFiles.Concat(SaferEnumerateFiles(dir, searchPattern, searchOption));
+                }
+                catch (UnauthorizedAccessException) { }
+                catch (PathTooLongException) { }
+            }
+
+            try
+            {
+                // Add files from the current directory
+                foundFiles = foundFiles.Concat(Directory.EnumerateFiles(path, searchPattern));
+            }
+            catch (UnauthorizedAccessException) { }
+
+            return foundFiles;
         }
     }
 }

FileManager/PersistentDictionary.cs

@@ -30,8 +30,7 @@ namespace FileManager
             if (IsReadOnly)
                 return;
 
-            File.WriteAllText(Filepath, "{}");
-            System.Threading.Thread.Sleep(100);
+            createNewFile();
         }
 
         public string GetString(string propertyName)
@@ -205,9 +204,39 @@ namespace FileManager
 
         private JObject readFile()
         {
+            if (!File.Exists(Filepath))
+            {
+                var msg = "Unrecoverable error. Settings file cannot be found";
+                var ex = new FileNotFoundException(msg, Filepath);
+                Serilog.Log.Logger.Error(ex, msg);
+                throw ex;
+            }
+
             var settingsJsonContents = File.ReadAllText(Filepath);
+
+            if (string.IsNullOrWhiteSpace(settingsJsonContents))
+            {
+                createNewFile();
+                settingsJsonContents = File.ReadAllText(Filepath);
+            }
+
             var jObject = JsonConvert.DeserializeObject<JObject>(settingsJsonContents);
+
+            if (jObject is null)
+            {
+                var msg = "Unrecoverable error. Unable to read settings from Settings file";
+                var ex = new NullReferenceException(msg);
+                Serilog.Log.Logger.Error(ex, msg);
+                throw ex;
+            }
+
             return jObject;
         }
+
+        private void createNewFile()
+        {
+            File.WriteAllText(Filepath, "{}");
+            System.Threading.Thread.Sleep(100);
+        }
     }
 }

FileManager/_InternalsVisible.cs

@@ -0,0 +1 @@
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo(nameof(FileManager) + ".Tests")]

Hoopla/Hoopla.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
 </Project>

InternalUtilities/InternalUtilities.csproj

@@ -1,15 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="AudibleApi" Version="2.2.0.1" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <ProjectReference Include="..\FileManager\FileManager.csproj" />
-  </ItemGroup>
-
-</Project>

Libation.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 16
-VisualStudioVersion = 16.0.28803.156
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "_Solution Items", "_Solution Items", "{03C8835F-936C-4AF7-87AE-FF92BDBE8B9B}"
 	ProjectSection(SolutionItems) = preProject
@@ -23,13 +23,13 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "2 Utilities (domain ignoran
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AaxDecrypter", "AaxDecrypter\AaxDecrypter.csproj", "{8BD8E012-F44F-4EE2-A234-D66C14D5FE4B}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FileManager", "FileManager\FileManager.csproj", "{1AE65B61-9C05-4C80-ABFF-48F16E22FDF1}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LibationFileManager", "LibationFileManager\LibationFileManager.csproj", "{1AE65B61-9C05-4C80-ABFF-48F16E22FDF1}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DataLayer", "DataLayer\DataLayer.csproj", "{59A10DF3-63EC-43F1-A3BF-4000CFA118D2}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FileLiberator", "FileLiberator\FileLiberator.csproj", "{393B5B27-D15C-4F77-9457-FA14BA8F3C73}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "InternalUtilities", "InternalUtilities\InternalUtilities.csproj", "{06882742-27A6-4347-97D9-56162CEC9C11}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AudibleUtilities", "AudibleUtilities\AudibleUtilities.csproj", "{06882742-27A6-4347-97D9-56162CEC9C11}"
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "3 Domain Internal Utilities (db ignorant)", "3 Domain Internal Utilities (db ignorant)", "{F0CBB7A7-D3FB-41FF-8F47-CF3F6A592249}"
 EndProject
@@ -46,8 +46,6 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ApplicationServices", "Appl
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "_Tests", "_Tests", "{67E66E82-5532-4440-AFB3-9FB1DF9DEF53}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "InternalUtilities.Tests", "_Tests\InternalUtilities.Tests\InternalUtilities.Tests.csproj", "{8447C956-B03E-4F59-9DD4-877793B849D9}"
-EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LibationSearchEngine.Tests", "_Tests\LibationSearchEngine.Tests\LibationSearchEngine.Tests.csproj", "{C5B21768-C7C9-4FCB-AC1E-187B223D5A98}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Hoopla", "Hoopla\Hoopla.csproj", "{D8F56E5A-3E65-41A6-B7E7-C4515A264B1F}"
@@ -56,6 +54,16 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LibationCli", "LibationCli\
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AppScaffolding", "AppScaffolding\AppScaffolding.csproj", "{595E7C4D-506D-486D-98B7-5FDDF398D033}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FileManager", "FileManager\FileManager.csproj", "{E86014F9-E4B3-4CD4-A210-2B3DB571DD86}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AudibleUtilities.Tests", "_Tests\AudibleUtilities.Tests\AudibleUtilities.Tests.csproj", "{788294BE-0D8E-40D4-9CEE-67896FBB52CE}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FileLiberator.Tests", "_Tests\FileLiberator.Tests\FileLiberator.Tests.csproj", "{5B8FC827-BF58-4CB1-A59E-BDEB9C62A05E}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FileManager.Tests", "_Tests\FileManager.Tests\FileManager.Tests.csproj", "{F2E04270-4551-41C4-99FF-E7125BED708C}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LibationFileManager.Tests", "_Tests\LibationFileManager.Tests\LibationFileManager.Tests.csproj", "{EB781571-8548-477E-82AD-FB9FAB548D2F}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -98,10 +106,6 @@ Global
 		{B95650EA-25F0-449E-BA5D-99126BC5D730}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{B95650EA-25F0-449E-BA5D-99126BC5D730}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{B95650EA-25F0-449E-BA5D-99126BC5D730}.Release|Any CPU.Build.0 = Release|Any CPU
-		{8447C956-B03E-4F59-9DD4-877793B849D9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{8447C956-B03E-4F59-9DD4-877793B849D9}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{8447C956-B03E-4F59-9DD4-877793B849D9}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{8447C956-B03E-4F59-9DD4-877793B849D9}.Release|Any CPU.Build.0 = Release|Any CPU
 		{C5B21768-C7C9-4FCB-AC1E-187B223D5A98}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{C5B21768-C7C9-4FCB-AC1E-187B223D5A98}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{C5B21768-C7C9-4FCB-AC1E-187B223D5A98}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -118,6 +122,26 @@ Global
 		{595E7C4D-506D-486D-98B7-5FDDF398D033}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{595E7C4D-506D-486D-98B7-5FDDF398D033}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{595E7C4D-506D-486D-98B7-5FDDF398D033}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E86014F9-E4B3-4CD4-A210-2B3DB571DD86}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E86014F9-E4B3-4CD4-A210-2B3DB571DD86}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E86014F9-E4B3-4CD4-A210-2B3DB571DD86}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E86014F9-E4B3-4CD4-A210-2B3DB571DD86}.Release|Any CPU.Build.0 = Release|Any CPU
+		{788294BE-0D8E-40D4-9CEE-67896FBB52CE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{788294BE-0D8E-40D4-9CEE-67896FBB52CE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{788294BE-0D8E-40D4-9CEE-67896FBB52CE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{788294BE-0D8E-40D4-9CEE-67896FBB52CE}.Release|Any CPU.Build.0 = Release|Any CPU
+		{5B8FC827-BF58-4CB1-A59E-BDEB9C62A05E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{5B8FC827-BF58-4CB1-A59E-BDEB9C62A05E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{5B8FC827-BF58-4CB1-A59E-BDEB9C62A05E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{5B8FC827-BF58-4CB1-A59E-BDEB9C62A05E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{F2E04270-4551-41C4-99FF-E7125BED708C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{F2E04270-4551-41C4-99FF-E7125BED708C}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{F2E04270-4551-41C4-99FF-E7125BED708C}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{F2E04270-4551-41C4-99FF-E7125BED708C}.Release|Any CPU.Build.0 = Release|Any CPU
+		{EB781571-8548-477E-82AD-FB9FAB548D2F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{EB781571-8548-477E-82AD-FB9FAB548D2F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{EB781571-8548-477E-82AD-FB9FAB548D2F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{EB781571-8548-477E-82AD-FB9FAB548D2F}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -132,11 +156,15 @@ Global
 		{635F00E1-AAD1-45F7-BEB7-D909AD33B9F6} = {8679CAC8-9164-4007-BDD2-F004810EDA14}
 		{401865F5-1942-4713-B230-04544C0A97B0} = {41CDCC73-9B81-49DD-9570-C54406E852AF}
 		{B95650EA-25F0-449E-BA5D-99126BC5D730} = {41CDCC73-9B81-49DD-9570-C54406E852AF}
-		{8447C956-B03E-4F59-9DD4-877793B849D9} = {67E66E82-5532-4440-AFB3-9FB1DF9DEF53}
 		{C5B21768-C7C9-4FCB-AC1E-187B223D5A98} = {67E66E82-5532-4440-AFB3-9FB1DF9DEF53}
 		{D8F56E5A-3E65-41A6-B7E7-C4515A264B1F} = {7FBBB086-0807-4998-85BF-6D1A49C8AD05}
 		{428163C3-D558-4914-B570-A92069521877} = {8679CAC8-9164-4007-BDD2-F004810EDA14}
 		{595E7C4D-506D-486D-98B7-5FDDF398D033} = {8679CAC8-9164-4007-BDD2-F004810EDA14}
+		{E86014F9-E4B3-4CD4-A210-2B3DB571DD86} = {43E3ACB3-E0BC-4370-8DBB-E3720C8C8FD1}
+		{788294BE-0D8E-40D4-9CEE-67896FBB52CE} = {67E66E82-5532-4440-AFB3-9FB1DF9DEF53}
+		{5B8FC827-BF58-4CB1-A59E-BDEB9C62A05E} = {67E66E82-5532-4440-AFB3-9FB1DF9DEF53}
+		{F2E04270-4551-41C4-99FF-E7125BED708C} = {67E66E82-5532-4440-AFB3-9FB1DF9DEF53}
+		{EB781571-8548-477E-82AD-FB9FAB548D2F} = {67E66E82-5532-4440-AFB3-9FB1DF9DEF53}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {615E00ED-BAEF-4E8E-A92A-9B82D87942A9}

LibationCli/LibationCli.csproj

@@ -3,7 +3,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
 
     <PublishTrimmed>true</PublishTrimmed>
     <PublishReadyToRun>true</PublishReadyToRun>

LibationCli/Options/ExportOptions.cs

@@ -3,8 +3,8 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 using ApplicationServices;
+using AudibleUtilities;
 using CommandLine;
-using InternalUtilities;
 
 namespace LibationCli
 {

LibationCli/Options/ScanOptions.cs

@@ -3,8 +3,8 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 using ApplicationServices;
+using AudibleUtilities;
 using CommandLine;
-using InternalUtilities;
 
 namespace LibationCli
 {
@@ -35,7 +35,8 @@ namespace LibationCli
 			var (TotalBooksProcessed, NewBooksAdded) = await LibraryCommands.ImportAccountAsync((a) => ApiExtended.CreateAsync(a), _accounts);
 
 			Console.WriteLine("Scan complete.");
-			Console.WriteLine($"Total processed: {TotalBooksProcessed}\r\nNew: {NewBooksAdded}");
+			Console.WriteLine($"Total processed: {TotalBooksProcessed}");
+			Console.WriteLine($"New: {NewBooksAdded}");
 		}
 
 		private Account[] getAccounts()

LibationFileManager/AudibleFileStorage.cs

@@ -0,0 +1,106 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+using FileManager;
+
+namespace LibationFileManager
+{
+    public abstract class AudibleFileStorage
+    {
+        protected abstract string GetFilePathCustom(string productId);
+
+        #region static
+        public static string DownloadsInProgressDirectory => Directory.CreateDirectory(Path.Combine(Configuration.Instance.InProgress, "DownloadsInProgress")).FullName;
+        public static string DecryptInProgressDirectory => Directory.CreateDirectory(Path.Combine(Configuration.Instance.InProgress, "DecryptInProgress")).FullName;
+
+        private static AaxcFileStorage AAXC { get; } = new AaxcFileStorage();
+        public static bool AaxcExists(string productId) => AAXC.Exists(productId);
+
+        public static AudioFileStorage Audio { get; } = new AudioFileStorage();
+
+        public static string BooksDirectory
+        {
+            get
+            {
+                if (string.IsNullOrWhiteSpace(Configuration.Instance.Books))
+                    Configuration.Instance.Books = Path.Combine(Configuration.UserProfile, "Books");
+                return Directory.CreateDirectory(Configuration.Instance.Books).FullName;
+            }
+        }
+        #endregion
+
+        #region instance
+        private FileType FileType { get; }
+        private string regexTemplate { get; }
+
+        protected AudibleFileStorage(FileType fileType)
+        {
+            FileType = fileType;
+
+            var extAggr = FileTypes.GetExtensions(FileType).Aggregate((a, b) => $"{a}|{b}");
+            regexTemplate = $@"{{0}}.*?\.({extAggr})$";
+        }
+
+        protected string GetFilePath(string productId)
+        {
+            // primary lookup
+            var cachedFile = FilePathCache.GetFirstPath(productId, FileType);
+            if (cachedFile is not null && File.Exists(cachedFile))
+                return cachedFile;
+
+            // secondary lookup attempt
+            var firstOrNull = GetFilePathCustom(productId);
+            if (firstOrNull is not null)
+                FilePathCache.Insert(productId, firstOrNull);
+
+            return firstOrNull;
+        }
+
+        protected Regex GetBookSearchRegex(string productId)
+        {
+            var pattern = string.Format(regexTemplate, productId);
+            return new Regex(pattern, RegexOptions.IgnoreCase);
+        }
+        #endregion
+    }
+
+    internal class AaxcFileStorage : AudibleFileStorage
+    {
+        internal AaxcFileStorage() : base(FileType.AAXC) { }
+
+        protected override string GetFilePathCustom(string productId)
+        {
+            var regex = GetBookSearchRegex(productId);
+            return FileUtility
+                .SaferEnumerateFiles(DownloadsInProgressDirectory, "*.*", SearchOption.AllDirectories)
+                .FirstOrDefault(s => regex.IsMatch(s));
+        }
+
+        public bool Exists(string productId) => GetFilePath(productId) != null;
+    }
+
+    public class AudioFileStorage : AudibleFileStorage
+    {
+        internal AudioFileStorage() : base(FileType.Audio)
+            => BookDirectoryFiles ??= new BackgroundFileSystem(BooksDirectory, "*.*", SearchOption.AllDirectories);
+
+        private static BackgroundFileSystem BookDirectoryFiles { get; set; }
+        private static object bookDirectoryFilesLocker { get; } = new();
+        protected override string GetFilePathCustom(string productId)
+        {
+            // If user changed the BooksDirectory: reinitialize
+            lock (bookDirectoryFilesLocker)
+                if (BooksDirectory != BookDirectoryFiles.RootDirectory)
+                    BookDirectoryFiles = new BackgroundFileSystem(BooksDirectory, "*.*", SearchOption.AllDirectories);
+
+            var regex = GetBookSearchRegex(productId);
+            return BookDirectoryFiles.FindFile(regex);
+        }
+
+        public void Refresh() => BookDirectoryFiles.RefreshFiles();
+
+        public string GetPath(string productId) => GetFilePath(productId);
+    }
+}

LibationFileManager/Configuration.cs

@@ -5,13 +5,14 @@ using System.IO;
 using System.Linq;
 using Dinah.Core;
 using Dinah.Core.Logging;
+using FileManager;
 using Microsoft.Extensions.Configuration;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 using Serilog;
 using Serilog.Events;
 
-namespace FileManager
+namespace LibationFileManager
 {
     public class Configuration
     {
@@ -132,6 +133,13 @@ namespace FileManager
             set => persistentDictionary.SetString(nameof(BadBook), value.ToString());
         }
 
+        [Description("Show number of newly imported titles? When unchecked, no pop-up will appear after library scan.")]
+        public bool ShowImportedStats
+        {
+            get => persistentDictionary.GetNonString<bool>(nameof(ShowImportedStats));
+            set => persistentDictionary.SetNonString(nameof(ShowImportedStats), value);
+        }
+
         [Description("Import episodes? (eg: podcasts) When unchecked, episodes will not be imported into Libation.")]
         public bool ImportEpisodes
         {
@@ -144,8 +152,40 @@ namespace FileManager
         {
             get => persistentDictionary.GetNonString<bool>(nameof(DownloadEpisodes));
             set => persistentDictionary.SetNonString(nameof(DownloadEpisodes), value);
+		}
+
+        #region templates: custom file naming
+
+        [Description("How to format the folders in which files will be saved")]
+		public string FolderTemplate
+        {
+            get => getTemplate(nameof(FolderTemplate), Templates.Folder);
+            set => setTemplate(nameof(FolderTemplate), Templates.Folder, value);
         }
 
+        [Description("How to format the saved pdf and audio files")]
+		public string FileTemplate
+        {
+            get => getTemplate(nameof(FileTemplate), Templates.File);
+            set => setTemplate(nameof(FileTemplate), Templates.File, value);
+        }
+
+        [Description("How to format the saved audio files when split by chapters")]
+        public string ChapterFileTemplate
+        {
+            get => getTemplate(nameof(ChapterFileTemplate), Templates.ChapterFile);
+            set => setTemplate(nameof(ChapterFileTemplate), Templates.ChapterFile, value);
+        }
+
+        private string getTemplate(string settingName, Templates templ) => templ.GetValid(persistentDictionary.GetString(settingName));
+        private void setTemplate(string settingName, Templates templ, string newValue)
+        {
+            var template = newValue?.Trim();
+            if (templ.IsValid(template))
+                persistentDictionary.SetString(settingName, template);
+        }
+        #endregion
+
         #endregion
 
         #region known directories
@@ -230,7 +270,7 @@ namespace FileManager
                 var valueWasChanged = persistentDictionary.SetWithJsonPath("Serilog", "MinimumLevel", value.ToString());
                 if (!valueWasChanged)
                 {
-                    Log.Logger.Information("LogLevel.set attempt. No change");
+                    Log.Logger.Debug("LogLevel.set attempt. No change");
                     return;
                 }
 

LibationFileManager/FilePathCache.cs

@@ -0,0 +1,115 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using Dinah.Core.Collections.Immutable;
+using Newtonsoft.Json;
+
+namespace LibationFileManager
+{
+	public static class FilePathCache
+	{
+		public record CacheEntry(string Id, FileType FileType, string Path);
+
+		private const string FILENAME = "FileLocations.json";
+
+		public static event EventHandler<CacheEntry> Inserted;
+		public static event EventHandler<CacheEntry> Removed;
+
+		private static Cache<CacheEntry> cache { get; } = new Cache<CacheEntry>();
+
+		private static string jsonFile => Path.Combine(Configuration.Instance.LibationFiles, FILENAME);
+
+        static FilePathCache()
+        {
+			// load json into memory. if file doesn't exist, nothing to do. save() will create if needed
+			if (File.Exists(jsonFile))
+			{
+				var list = JsonConvert.DeserializeObject<List<CacheEntry>>(File.ReadAllText(jsonFile));
+
+				// file exists but deser is null. this will never happen when file is healthy
+				if (list is null)
+				{
+					lock (locker)
+					{
+						Serilog.Log.Logger.Error("Error deserializing file. Wrong format. Possibly corrupt. Deleting file. {@DebugInfo}", new { jsonFile });
+						File.Delete(jsonFile);
+						return;
+					}
+				}
+
+				cache = new Cache<CacheEntry>(list);
+			}
+        }
+
+        public static bool Exists(string id, FileType type) => GetFirstPath(id, type) != null;
+
+		public static List<(FileType fileType, string path)> GetFiles(string id)
+			=> getEntries(entry => entry.Id == id)
+			.Select(entry => (entry.FileType, entry.Path))
+			.ToList();
+
+		public static string GetFirstPath(string id, FileType type)
+			=> getEntries(entry => entry.Id == id && entry.FileType == type)
+			?.FirstOrDefault()
+			?.Path;
+
+		private static List<CacheEntry> getEntries(Func<CacheEntry, bool> predicate)
+		{
+			var entries = cache.Where(predicate).ToList();
+			if (entries is null || !entries.Any())
+				return null;
+
+			remove(entries.Where(e => !File.Exists(e.Path)).ToList());
+
+			return entries;
+		}
+
+		private static void remove(List<CacheEntry> entries)
+		{
+			if (entries is null)
+				return;
+
+			lock (locker)
+			{
+				foreach (var entry in entries)
+				{
+					cache.Remove(entry);
+					Removed?.Invoke(null, entry);
+				}
+				save();
+			}
+		}
+
+        public static void Insert(string id, string path)
+		{
+			var type = FileTypes.GetFileTypeFromPath(path);
+			var entry = new CacheEntry(id, type, path);
+			cache.Add(entry);
+			Inserted?.Invoke(null, entry);
+			save();
+		}
+
+		// cache is thread-safe and lock free. but file saving is not
+		private static object locker { get; } = new object();
+		private static void save()
+		{
+			// create json if not exists
+			static void resave() => File.WriteAllText(jsonFile, JsonConvert.SerializeObject(cache.ToList(), Formatting.Indented));
+
+			lock (locker)
+			{
+				try { resave(); }
+				catch (IOException)
+				{
+					try { resave(); }
+					catch (IOException ex)
+					{
+						Serilog.Log.Logger.Error(ex, $"Error saving {FILENAME}");
+						throw;
+					}
+				}
+			}
+        }
+    }
+}

LibationFileManager/FileTypes.cs

@@ -0,0 +1,39 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+
+namespace LibationFileManager
+{
+	public enum FileType { Unknown, Audio, AAXC, PDF, Zip, Cue }
+
+	public static class FileTypes
+	{
+		private static Dictionary<string, FileType> dic => new()
+		{
+			["aaxc"] = FileType.AAXC,
+			["cue"] = FileType.Cue,
+			["pdf"] = FileType.PDF,
+			["zip"] = FileType.Zip,
+
+			["aac"] = FileType.Audio,
+			["flac"] = FileType.Audio,
+			["m4a"] = FileType.Audio,
+			["m4b"] = FileType.Audio,
+			["mp3"] = FileType.Audio,
+			["mp4"] = FileType.Audio,
+			["ogg"] = FileType.Audio,
+		};
+
+		public static FileType GetFileTypeFromPath(string path)
+			=> dic.TryGetValue(Path.GetExtension(path).ToLower().Trim('.'), out var fileType)
+			? fileType
+			: FileType.Unknown;
+
+		public static List<string> GetExtensions(FileType fileType)
+			=> dic
+			.Where(kvp => kvp.Value == fileType)
+			.Select(kvp => kvp.Key)
+			.ToList();
+	}
+}

LibationFileManager/LibationFileManager.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0-windows</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="6.0.0" />
+    <PackageReference Include="Serilog.Exceptions" Version="8.1.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\AaxDecrypter\AaxDecrypter.csproj" />
+    <ProjectReference Include="..\FileManager\FileManager.csproj" />
+  </ItemGroup>
+
+</Project>

LibationFileManager/LibraryBookDto.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace LibationFileManager
+{
+    public class BookDto
+    {
+        public string AudibleProductId { get; set; }
+        public string Title { get; set; }
+        public string Locale { get; set; }
+
+        public IEnumerable<string> Authors { get; set; }
+        public string AuthorNames => string.Join(", ", Authors);
+        public string FirstAuthor => Authors.FirstOrDefault();
+
+        public IEnumerable<string> Narrators { get; set; }
+        public string NarratorNames => string.Join(", ", Narrators);
+        public string FirstNarrator => Narrators.FirstOrDefault();
+
+        public string SeriesName { get; set; }
+        public string SeriesNumber { get; set; }
+    }
+
+    public class LibraryBookDto : BookDto
+    {
+        public string Account { get; set; }
+    }
+}

LibationFileManager/PictureStorage.cs

@@ -6,7 +6,7 @@ using System.Linq;
 using System.Net.Http;
 using System.Threading.Tasks;
 
-namespace FileManager
+namespace LibationFileManager
 {
 	public enum PictureSize { _80x80 = 80, _300x300 = 300, _500x500 = 500 }
 	public class PictureCachedEventArgs : EventArgs
@@ -73,16 +73,10 @@ namespace FileManager
 				if (!cache.ContainsKey(def) || cache[def] == null)
 				{
 					var path = getPath(def);
-					byte[] bytes;
-
-					if (File.Exists(path))
-						bytes = File.ReadAllBytes(path);
-					else
-					{
-						bytes = downloadBytes(def);
-						saveFile(def, bytes);
-					}
-
+					var bytes
+						= File.Exists(path)
+						? File.ReadAllBytes(path)
+						: downloadBytes(def);
 					cache[def] = bytes;
 				}
 				return cache[def];
@@ -104,7 +98,6 @@ namespace FileManager
 					continue;
 
 				var bytes = downloadBytes(def);
-				saveFile(def, bytes);
 				lock (cacheLocker)
 					cache[def] = bytes;
 
@@ -115,14 +108,24 @@ namespace FileManager
 		private static HttpClient imageDownloadClient { get; } = new HttpClient();
 		private static byte[] downloadBytes(PictureDefinition def)
 		{
-			var sz = (int)def.Size;
-			return imageDownloadClient.GetByteArrayAsync("ht" + $"tps://images-na.ssl-images-amazon.com/images/I/{def.PictureId}._SL{sz}_.jpg").Result;
-		}
+			if (def.PictureId is null)
+				return getDefaultImage(def.Size);
 
-		private static void saveFile(PictureDefinition def, byte[] bytes)
-		{
-			var path = getPath(def);
-			File.WriteAllBytes(path, bytes);
+			try
+			{
+				var sz = (int)def.Size;
+				var bytes = imageDownloadClient.GetByteArrayAsync("ht" + $"tps://images-na.ssl-images-amazon.com/images/I/{def.PictureId}._SL{sz}_.jpg").Result;
+
+				// save image file. make sure to not save default image
+				var path = getPath(def);
+				File.WriteAllBytes(path, bytes);
+
+				return bytes;
+			}
+			catch
+			{
+				return getDefaultImage(def.Size);
+			}
 		}
 	}
 }

LibationFileManager/QuickFilters.cs

@@ -5,7 +5,7 @@ using System.Linq;
 using Dinah.Core.Collections.Generic;
 using Newtonsoft.Json;
 
-namespace FileManager
+namespace LibationFileManager
 {
     public static class QuickFilters
     {

LibationFileManager/SqliteStorage.cs

@@ -1,11 +1,11 @@
 using System.IO;
 
-namespace FileManager
+namespace LibationFileManager
 {
 	public static class SqliteStorage
 	{
 		// not customizable. don't move to config
 		private static string databasePath => Path.Combine(Configuration.Instance.LibationFiles, "LibationContext.db");
-		public static string ConnectionString => $"Data Source={databasePath};Foreign Keys=False;";
+		public static string ConnectionString => $"Data Source={databasePath};Foreign Keys=False;Pooling=False;";
 	}
 }

LibationFileManager/TagsPersistence.cs

@@ -6,7 +6,7 @@ using Newtonsoft.Json;
 using Polly;
 using Polly.Retry;
 
-namespace FileManager
+namespace LibationFileManager
 {
     /// <summary>
     /// Tags must also be stored in db for search performance. Stored in json file to survive a db reset.
@@ -54,11 +54,17 @@ namespace FileManager
 
 		private static void ensureCache()
 		{
-			if (cache is null)
-				lock (locker)
-					cache = !File.Exists(TagsFile)
-						? new Dictionary<string, string>()
-						: JsonConvert.DeserializeObject<Dictionary<string, string>>(File.ReadAllText(TagsFile));
+			if (cache is not null)
+				return;
+
+			lock (locker)
+			{
+				if (File.Exists(TagsFile))
+					cache = JsonConvert.DeserializeObject<Dictionary<string, string>>(File.ReadAllText(TagsFile));
+
+				// if file doesn't exist. or if file is corrupt and deserialize returns null
+				cache ??= new Dictionary<string, string>();
+			}
 		}
 	}
 }

LibationFileManager/TemplateTags.cs

@@ -0,0 +1,44 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Dinah.Core;
+
+namespace LibationFileManager
+{
+    public sealed class TemplateTags : Enumeration<TemplateTags>
+    {
+        public string TagName => DisplayName;
+        public string Description { get; }
+        public bool IsChapterOnly { get; }
+
+        private static int value = 0;
+        private TemplateTags(string tagName, string description, bool isChapterOnly = false) : base(value++, tagName)
+        {
+            Description = description;
+            IsChapterOnly = isChapterOnly;
+        }
+
+        // putting these first is the incredibly lazy way to make them show up first in the EditTemplateDialog
+        public static TemplateTags ChCount { get; } = new TemplateTags("ch count", "Number of chapters", true);
+        public static TemplateTags ChTitle { get; } = new TemplateTags("ch title", "Chapter title", true);
+        public static TemplateTags ChNumber { get; } = new TemplateTags("ch#", "Chapter #", true);
+        public static TemplateTags ChNumber0 { get; } = new TemplateTags("ch# 0", "Chapter # with leading zeros", true);
+
+        public static TemplateTags Id { get; } = new TemplateTags("id", "Audible ID");
+        public static TemplateTags Title { get; } = new TemplateTags("title", "Full title");
+        public static TemplateTags TitleShort { get; } = new TemplateTags("title short", "Title. Stop at first colon");
+        public static TemplateTags Author { get; } = new TemplateTags("author", "Author(s)");
+        public static TemplateTags FirstAuthor { get; } = new TemplateTags("first author", "First author");
+        public static TemplateTags Narrator { get; } = new TemplateTags("narrator", "Narrator(s)");
+        public static TemplateTags FirstNarrator { get; } = new TemplateTags("first narrator", "First narrator");
+        public static TemplateTags Series { get; } = new TemplateTags("series", "Name of series");
+        // can't also have a leading zeros version. Too many weird edge cases. Eg: "1-4"
+        public static TemplateTags SeriesNumber { get; } = new TemplateTags("series#", "Number order in series");
+        public static TemplateTags Account { get; } = new TemplateTags("account", "Audible account of this book");
+        public static TemplateTags Locale { get; } = new TemplateTags("locale", "Region/country");
+
+        // Special case. Isn't mapped to a replacement in Templates.cs
+        // Included here for display by EditTemplateDialog
+        public static TemplateTags IfSeries { get; } = new TemplateTags("if series->...<-if series", "Only include if part of a series");
+    }
+}

LibationFileManager/Templates.cs

@@ -0,0 +1,284 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+using Dinah.Core;
+using FileManager;
+
+namespace LibationFileManager
+{
+    public abstract class Templates
+    {
+        protected static string[] Valid => Array.Empty<string>();
+        public const string ERROR_NULL_IS_INVALID = "Null template is invalid.";
+        public const string ERROR_FULL_PATH_IS_INVALID = @"No colons or full paths allowed. Eg: should not start with C:\";
+        public const string ERROR_INVALID_FILE_NAME_CHAR = @"Only file name friendly characters allowed. Eg: no colons or slashes";
+
+        public const string WARNING_EMPTY = "Template is empty.";
+        public const string WARNING_WHITE_SPACE = "Template is white space.";
+        public const string WARNING_NO_TAGS = "Should use tags. Eg: <title>";
+        public const string WARNING_HAS_CHAPTER_TAGS = "Chapter tags should only be used in the template used for naming files which are split by chapter. Eg: <ch title>";
+        public const string WARNING_NO_CHAPTER_NUMBER_TAG = "Should include chapter number tag in template used for naming files which are split by chapter. Ie: <ch#> or <ch# 0>";
+
+        public static FolderTemplate Folder { get; } = new FolderTemplate();
+        public static FileTemplate File { get; } = new FileTemplate();
+        public static ChapterFileTemplate ChapterFile { get; } = new ChapterFileTemplate();
+
+        public abstract string Name { get; }
+        public abstract string Description { get; }
+        public abstract string DefaultTemplate { get; }
+        protected abstract bool IsChapterized { get; }
+
+        protected Templates() { }
+
+		#region validation
+		internal string GetValid(string configValue)
+        {
+            var value = configValue?.Trim();
+            return IsValid(value) ? value : DefaultTemplate;
+        }
+
+        public abstract IEnumerable<string> GetErrors(string template);
+        public bool IsValid(string template) => !GetErrors(template).Any();
+
+        public abstract IEnumerable<string> GetWarnings(string template);
+        public bool HasWarnings(string template) => GetWarnings(template).Any();
+
+        protected static string[] GetFileErrors(string template)
+        {
+            // File name only; not path. all other path chars are valid enough to pass this check and will be handled on final save.
+
+            // null is invalid. whitespace is valid but not recommended
+            if (template is null)
+                return new[] { ERROR_NULL_IS_INVALID };
+
+            if (template.Contains(':')
+                || template.Contains(Path.DirectorySeparatorChar)
+                || template.Contains(Path.AltDirectorySeparatorChar)
+                )
+                return new[] { ERROR_INVALID_FILE_NAME_CHAR };
+
+            return Valid;
+        }
+
+        protected IEnumerable<string> GetStandardWarnings(string template)
+        {
+            var warnings = GetErrors(template).ToList();
+            if (template is null)
+                return warnings;
+
+            if (string.IsNullOrEmpty(template))
+                warnings.Add(WARNING_EMPTY);
+            else if (string.IsNullOrWhiteSpace(template))
+                warnings.Add(WARNING_WHITE_SPACE);
+
+            if (TagCount(template) == 0)
+                warnings.Add(WARNING_NO_TAGS);
+
+            if (!IsChapterized && ContainsChapterOnlyTags(template))
+                warnings.Add(WARNING_HAS_CHAPTER_TAGS);
+
+            return warnings;
+        }
+
+        internal int TagCount(string template)
+            => GetTemplateTags()
+            // for <id><id> == 1, use:
+            //   .Count(t => template.Contains($"<{t.TagName}>"))
+            // .Sum() impl: <id><id> == 2
+            .Sum(t => template.Split($"<{t.TagName}>").Length - 1);
+
+        internal static bool ContainsChapterOnlyTags(string template)
+            => TemplateTags.GetAll()
+            .Where(t => t.IsChapterOnly)
+            .Any(t => ContainsTag(template, t.TagName));
+
+        internal static bool ContainsTag(string template, string tag) => template.Contains($"<{tag}>");
+        #endregion
+
+        #region to file name
+        /// <summary>
+        /// EditTemplateDialog: Get template generated filename for portion of path
+        /// </summary>
+        public string GetPortionFilename(LibraryBookDto libraryBookDto, string template)
+            => string.IsNullOrWhiteSpace(template)
+            ? ""
+            : getFileNamingTemplate(libraryBookDto, template, null, null)
+            .GetFilePath();
+
+        private static Regex ifSeriesRegex { get; } = new Regex("<if series->(.*?)<-if series>", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+
+        internal static FileNamingTemplate getFileNamingTemplate(LibraryBookDto libraryBookDto, string template, string dirFullPath, string extension)
+        {
+            ArgumentValidator.EnsureNotNullOrWhiteSpace(template, nameof(template));
+            ArgumentValidator.EnsureNotNull(libraryBookDto, nameof(libraryBookDto));
+
+            dirFullPath = dirFullPath?.Trim() ?? "";
+
+            // for non-series, remove <if series-> and <-if series> tags and everything in between
+            // for series, remove <if series-> and <-if series> tags, what's in between will remain
+            template = ifSeriesRegex.Replace(
+                template,
+                string.IsNullOrWhiteSpace(libraryBookDto.SeriesName) ? "" : "$1");
+
+            var t = template + FileUtility.GetStandardizedExtension(extension);
+            var fullfilename = dirFullPath == "" ? t : Path.Combine(dirFullPath, t);
+
+            var fileNamingTemplate = new FileNamingTemplate(fullfilename) { IllegalCharacterReplacements = "_" };
+
+            var title = libraryBookDto.Title ?? "";
+            var titleShort = title.IndexOf(':') < 1 ? title : title.Substring(0, title.IndexOf(':'));
+
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Id, libraryBookDto.AudibleProductId);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Title, title);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.TitleShort, titleShort);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Author, libraryBookDto.AuthorNames);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.FirstAuthor, libraryBookDto.FirstAuthor);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Narrator, libraryBookDto.NarratorNames);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.FirstNarrator, libraryBookDto.FirstNarrator);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Series, libraryBookDto.SeriesName);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.SeriesNumber, libraryBookDto.SeriesNumber);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Account, libraryBookDto.Account);
+            fileNamingTemplate.AddParameterReplacement(TemplateTags.Locale, libraryBookDto.Locale);
+
+            return fileNamingTemplate;
+        }
+        #endregion
+
+        public IEnumerable<TemplateTags> GetTemplateTags()
+            => TemplateTags.GetAll()
+            // yeah, this line is a little funky but it works when you think through it. also: trust the unit tests
+            .Where(t => IsChapterized || !t.IsChapterOnly);
+
+        public string Sanitize(string template)
+        {
+            var value = template ?? "";
+
+            // don't use alt slash
+            value = value.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar);
+
+            // don't allow double slashes
+            var sing = $"{Path.DirectorySeparatorChar}";
+            var dbl = $"{Path.DirectorySeparatorChar}{Path.DirectorySeparatorChar}";
+            while (value.Contains(dbl))
+                value = value.Replace(dbl, sing);
+
+            // trim. don't start or end with slash
+            while (true)
+            {
+                var start = value.Length;
+                value = value
+                    .Trim()
+                    .Trim(Path.DirectorySeparatorChar);
+                var end = value.Length;
+                if (start == end)
+                    break;
+            }
+
+            return value;
+        }
+
+        public class FolderTemplate : Templates
+        {
+			public override string Name => "Folder Template";
+            public override string Description => Configuration.GetDescription(nameof(Configuration.FolderTemplate));
+			public override string DefaultTemplate { get; } = "<title short> [<id>]";
+            protected override bool IsChapterized { get; } = false;
+
+            internal FolderTemplate() : base() { }
+
+            #region validation
+            public override IEnumerable<string> GetErrors(string template)
+            {
+                // null is invalid. whitespace is valid but not recommended
+                if (template is null)
+                    return new[] { ERROR_NULL_IS_INVALID };
+
+                // must be relative. no colons. all other path chars are valid enough to pass this check and will be handled on final save.
+                if (template.Contains(':'))
+                    return new[] { ERROR_FULL_PATH_IS_INVALID };
+
+                return Valid;
+            }
+            
+            public override IEnumerable<string> GetWarnings(string template) => GetStandardWarnings(template);
+            #endregion
+
+            #region to file name
+            /// <summary>USES LIVE CONFIGURATION VALUES</summary>
+            public string GetFilename(LibraryBookDto libraryBookDto)
+                => getFileNamingTemplate(libraryBookDto, Configuration.Instance.FolderTemplate, AudibleFileStorage.BooksDirectory, null)
+                .GetFilePath();
+            #endregion
+        }
+
+        public class FileTemplate : Templates
+        {
+            public override string Name => "File Template";
+            public override string Description => Configuration.GetDescription(nameof(Configuration.FileTemplate));
+            public override string DefaultTemplate { get; } = "<title> [<id>]";
+            protected override bool IsChapterized { get; } = false;
+
+            internal FileTemplate() : base() { }
+
+            #region validation
+            public override IEnumerable<string> GetErrors(string template) => GetFileErrors(template);
+
+            public override IEnumerable<string> GetWarnings(string template) => GetStandardWarnings(template);
+            #endregion
+
+            #region to file name
+            /// <summary>USES LIVE CONFIGURATION VALUES</summary>
+            public string GetFilename(LibraryBookDto libraryBookDto, string dirFullPath, string extension)
+                => getFileNamingTemplate(libraryBookDto, Configuration.Instance.FileTemplate, dirFullPath, extension)
+                .GetFilePath();
+            #endregion
+        }
+
+        public class ChapterFileTemplate : Templates
+        {
+            public override string Name => "Chapter File Template";
+            public override string Description => Configuration.GetDescription(nameof(Configuration.ChapterFileTemplate));
+            public override string DefaultTemplate { get; } = "<title> [<id>] - <ch# 0> - <ch title>";
+            protected override bool IsChapterized { get; } = true;
+
+            internal ChapterFileTemplate() : base() { }
+
+            #region validation
+            public override IEnumerable<string> GetErrors(string template) => GetFileErrors(template);
+
+            public override IEnumerable<string> GetWarnings(string template)
+            {
+                var warnings = GetStandardWarnings(template).ToList();
+                if (template is null)
+                    return warnings;
+
+                // recommended to incl. <ch#> or <ch# 0>
+                if (!ContainsTag(template, TemplateTags.ChNumber.TagName) && !ContainsTag(template, TemplateTags.ChNumber0.TagName))
+                    warnings.Add(WARNING_NO_CHAPTER_NUMBER_TAG);
+
+                return warnings;
+            }
+            #endregion
+
+            #region to file name
+            /// <summary>USES LIVE CONFIGURATION VALUES</summary>
+            public string GetFilename(LibraryBookDto libraryBookDto, AaxDecrypter.MultiConvertFileProperties props)
+                => GetPortionFilename(libraryBookDto, Configuration.Instance.ChapterFileTemplate, props, AudibleFileStorage.DecryptInProgressDirectory);
+
+            public string GetPortionFilename(LibraryBookDto libraryBookDto, string template, AaxDecrypter.MultiConvertFileProperties props, string fullDirPath)
+            {
+                var fileNamingTemplate = getFileNamingTemplate(libraryBookDto, template, fullDirPath, Path.GetExtension(props.OutputFileName));
+
+                fileNamingTemplate.AddParameterReplacement(TemplateTags.ChCount, props.PartsTotal);
+                fileNamingTemplate.AddParameterReplacement(TemplateTags.ChNumber, props.PartsPosition);
+                fileNamingTemplate.AddParameterReplacement(TemplateTags.ChNumber0, FileUtility.GetSequenceFormatted(props.PartsPosition, props.PartsTotal));
+                fileNamingTemplate.AddParameterReplacement(TemplateTags.ChTitle, props.Title ?? "");
+
+                return fileNamingTemplate.GetFilePath();
+            }
+            #endregion
+        }
+    }
+}

LibationFileManager/UtilityExtensions.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using FileManager;
+
+namespace LibationFileManager
+{
+	public static class UtilityExtensions
+	{
+		public static void AddParameterReplacement(this FileNamingTemplate fileNamingTemplate, TemplateTags templateTags, object value)
+			=> fileNamingTemplate.AddParameterReplacement(templateTags.TagName, value);
+	}
+}

LibationFileManager/_InternalsVisible.cs

@@ -0,0 +1 @@
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo(nameof(LibationFileManager) + ".Tests")]

LibationSearchEngine/LibationSearchEngine.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0-windows</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
@@ -14,7 +14,6 @@
 
   <ItemGroup>
     <ProjectReference Include="..\DataLayer\DataLayer.csproj" />
-    <ProjectReference Include="..\FileManager\FileManager.csproj" />
   </ItemGroup>
 
 </Project>

LibationSearchEngine/SearchEngine.cs

@@ -5,7 +5,7 @@ using System.Linq;
 using System.Text.RegularExpressions;
 using DataLayer;
 using Dinah.Core;
-using FileManager;
+using LibationFileManager;
 using Lucene.Net.Analysis.Standard;
 using Lucene.Net.Documents;
 using Lucene.Net.Index;

LibationSearchEngine/_InternalsVisible.cs

@@ -0,0 +1 @@
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo(nameof(LibationSearchEngine) + ".Tests")]

LibationWinForms/BookLiberation/AudioConvertForm.cs

@@ -1,6 +1,6 @@
-using DataLayer;
-using FileManager;
-using System;
+using System;
+using DataLayer;
+using LibationFileManager;
 
 namespace LibationWinForms.BookLiberation
 {

LibationWinForms/BookLiberation/AudioDecodeForm.cs

@@ -2,6 +2,7 @@
 using DataLayer;
 using Dinah.Core.Net.Http;
 using Dinah.Core.Threading;
+using LibationFileManager;
 using LibationWinForms.BookLiberation.BaseForms;
 
 namespace LibationWinForms.BookLiberation
@@ -13,30 +14,25 @@ namespace LibationWinForms.BookLiberation
 
 		private Func<byte[]> GetCoverArtDelegate;
 
-		// book info
-		private string title;
-		private string authorNames;
-		private string narratorNames;
-
 		#region Processable event handler overrides
 		public override void Processable_Begin(object sender, LibraryBook libraryBook)
 		{
 			base.Processable_Begin(sender, libraryBook);
 
-			GetCoverArtDelegate = () => FileManager.PictureStorage.GetPictureSynchronously(
-						new FileManager.PictureDefinition(
+			GetCoverArtDelegate = () => PictureStorage.GetPictureSynchronously(
+						new PictureDefinition(
 							libraryBook.Book.PictureId,
-							FileManager.PictureSize._500x500));
+							PictureSize._500x500));
 
 			//Set default values from library
 			AudioDecodable_TitleDiscovered(sender, libraryBook.Book.Title);
-			AudioDecodable_AuthorsDiscovered(sender, string.Join(", ", libraryBook.Book.Authors));
-			AudioDecodable_NarratorsDiscovered(sender, string.Join(", ", libraryBook.Book.NarratorNames));
+			AudioDecodable_AuthorsDiscovered(sender, libraryBook.Book.AuthorNames);
+			AudioDecodable_NarratorsDiscovered(sender, libraryBook.Book.NarratorNames);
 			AudioDecodable_CoverImageDiscovered(sender,
-					FileManager.PictureStorage.GetPicture(
-						new FileManager.PictureDefinition(
+					PictureStorage.GetPicture(
+						new PictureDefinition(
 							libraryBook.Book.PictureId,
-							FileManager.PictureSize._80x80)).bytes);
+							PictureSize._80x80)).bytes);
 		}
 		#endregion
 
@@ -59,14 +55,23 @@ namespace LibationWinForms.BookLiberation
 			updateRemainingTime((int)timeRemaining.TotalSeconds);
 		}
 
+		private void updateRemainingTime(int remaining)
+			=> remainingTimeLbl.UIThreadAsync(() => remainingTimeLbl.Text = $"ETA:\r\n{formatTime(remaining)}");
+
+		private string formatTime(int seconds)
+		{
+			var timeSpan = new TimeSpan(0, 0, seconds);
+			return
+				timeSpan.TotalHours >= 1 ? $"{timeSpan:%h}h {timeSpan:mm}m {timeSpan:ss}s"
+				: timeSpan.TotalMinutes >= 1 ? $"{timeSpan:%m}m {timeSpan:ss}s"
+				: $"{seconds} sec";
+		}
 		#endregion
 
 		#region AudioDecodable event handlers
-		public override void AudioDecodable_RequestCoverArt(object sender, Action<byte[]> setCoverArtDelegate)
-		{
-			base.AudioDecodable_RequestCoverArt(sender, setCoverArtDelegate);
-			setCoverArtDelegate(GetCoverArtDelegate?.Invoke());
-		}
+		private string title;
+		private string authorNames;
+		private string narratorNames;
 
 		public override void AudioDecodable_TitleDiscovered(object sender, string title)
 		{
@@ -90,18 +95,20 @@ namespace LibationWinForms.BookLiberation
 			updateBookInfo();
 		}
 
+		private void updateBookInfo()
+			=> bookInfoLbl.UIThreadAsync(() => bookInfoLbl.Text = $"{title}\r\nBy {authorNames}\r\nNarrated by {narratorNames}");
+
+		public override void AudioDecodable_RequestCoverArt(object sender, Action<byte[]> setCoverArtDelegate)
+		{
+			base.AudioDecodable_RequestCoverArt(sender, setCoverArtDelegate);
+			setCoverArtDelegate(GetCoverArtDelegate?.Invoke());
+		}
+
 		public override void AudioDecodable_CoverImageDiscovered(object sender, byte[] coverArt)
 		{
 			base.AudioDecodable_CoverImageDiscovered(sender, coverArt);
 			pictureBox1.UIThreadAsync(() => pictureBox1.Image = Dinah.Core.Drawing.ImageReader.ToImage(coverArt));
 		}
 		#endregion
-
-		// thread-safe UI updates
-		private void updateBookInfo()
-			=> bookInfoLbl.UIThreadAsync(() => bookInfoLbl.Text = $"{title}\r\nBy {authorNames}\r\nNarrated by {narratorNames}");
-
-		private void updateRemainingTime(int remaining)
-			=> remainingTimeLbl.UIThreadAsync(() => remainingTimeLbl.Text = $"ETA:\r\n{remaining} sec");
 	}
 }

LibationWinForms/BookLiberation/AudioDecryptForm.cs

@@ -1,6 +1,6 @@
-using DataLayer;
-using FileManager;
-using System;
+using System;
+using DataLayer;
+using LibationFileManager;
 
 namespace LibationWinForms.BookLiberation
 {

LibationWinForms/BookLiberation/BaseForms/LiberationBaseForm.cs

@@ -152,11 +152,12 @@ namespace LibationWinForms.BookLiberation.BaseForms
 		#endregion
 
 		#region AudioDecodable event handlers
-		public virtual void AudioDecodable_RequestCoverArt(object sender, Action<byte[]> setCoverArtDelegate) { }
 		public virtual void AudioDecodable_TitleDiscovered(object sender, string title) { }
 		public virtual void AudioDecodable_AuthorsDiscovered(object sender, string authors) { }
 		public virtual void AudioDecodable_NarratorsDiscovered(object sender, string narrators) { }
+
 		public virtual void AudioDecodable_CoverImageDiscovered(object sender, byte[] coverArt) { }
+		public virtual void AudioDecodable_RequestCoverArt(object sender, Action<byte[]> setCoverArtDelegate) { }
 		#endregion
 	}
 }

LibationWinForms/BookLiberation/ProcessorAutomationController.cs

@@ -1,11 +1,11 @@
-using DataLayer;
-using Dinah.Core;
-using FileLiberator;
-using LibationWinForms.BookLiberation.BaseForms;
-using System;
-using System.Linq;
+using System;
 using System.Threading.Tasks;
 using System.Windows.Forms;
+using DataLayer;
+using Dinah.Core;
+using FileLiberator;
+using LibationFileManager;
+using LibationWinForms.BookLiberation.BaseForms;
 
 namespace LibationWinForms.BookLiberation
 {
@@ -218,12 +218,12 @@ namespace LibationWinForms.BookLiberation
 		{
 			LogMe.Error("ERROR. All books have not been processed. Most recent book: processing failed");
 
-			DialogResult? dialogResult = FileManager.Configuration.Instance.BadBook switch
+			DialogResult? dialogResult = Configuration.Instance.BadBook switch
 			{
-				FileManager.Configuration.BadBookAction.Abort => DialogResult.Abort,
-				FileManager.Configuration.BadBookAction.Retry => DialogResult.Retry,
-				FileManager.Configuration.BadBookAction.Ignore => DialogResult.Ignore,
-				FileManager.Configuration.BadBookAction.Ask => null,
+				Configuration.BadBookAction.Abort => DialogResult.Abort,
+				Configuration.BadBookAction.Retry => DialogResult.Retry,
+				Configuration.BadBookAction.Ignore => DialogResult.Ignore,
+				Configuration.BadBookAction.Ask => null,
 				_ => null
 			};
 

LibationWinForms/Dialogs/AccountsDialog.cs

@@ -1,9 +1,9 @@
-using AudibleApi;
-using InternalUtilities;
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Windows.Forms;
+using AudibleApi;
+using AudibleUtilities;
 
 namespace LibationWinForms.Dialogs
 {
@@ -112,6 +112,9 @@ namespace LibationWinForms.Dialogs
 		{
 			try
 			{
+				if (!inputIsValid())
+					return;
+
 				// without transaction, accounts persister will write ANY EDIT immediately to file
 				using var persister = AudibleApiStorage.GetAccountsSettingsPersister();
 
@@ -129,6 +132,28 @@ namespace LibationWinForms.Dialogs
 			}
 		}
 
+		private bool inputIsValid()
+		{
+			var dtos = getRowDtos();
+
+			foreach (var dto in dtos)
+			{
+				if (string.IsNullOrWhiteSpace(dto.AccountId))
+				{
+					MessageBox.Show("Account id cannot be blank. Please enter an account id for all accounts.", "Blank account", MessageBoxButtons.OK, MessageBoxIcon.Error);
+					return false;
+				}
+
+				if (string.IsNullOrWhiteSpace(dto.LocaleName))
+				{
+					MessageBox.Show("Please select a locale (i.e.: country or region) for all accounts.", "Blank region", MessageBoxButtons.OK, MessageBoxIcon.Error);
+					return false;
+				}
+			}
+
+			return true;
+		}
+
 		private void persist(AccountsSettings accountsSettings)
 		{
 			var existingAccounts = accountsSettings.Accounts;
@@ -152,11 +177,6 @@ namespace LibationWinForms.Dialogs
 			// upsert each. validation occurs through Account and AccountsSettings
 			foreach (var dto in dtos)
 			{
-				if (string.IsNullOrWhiteSpace(dto.AccountId))
-					throw new Exception("Please enter an account id for all accounts");
-				if (string.IsNullOrWhiteSpace(dto.LocaleName))
-					throw new Exception("Please select a locale (i.e.: country or region) for all accounts");
-
 				var acct = accountsSettings.Upsert(dto.AccountId, dto.LocaleName);
 				acct.LibraryScan = dto.LibraryScan;
 				acct.AccountName

LibationWinForms/Dialogs/BookDetailsDialog.cs

@@ -4,6 +4,7 @@ using System.Linq;
 using System.Windows.Forms;
 using DataLayer;
 using Dinah.Core;
+using LibationFileManager;
 
 namespace LibationWinForms.Dialogs
 {
@@ -39,7 +40,7 @@ namespace LibationWinForms.Dialogs
 		{
 			this.Text = Book.Title;
 
-			(var isDefault, var picture) = FileManager.PictureStorage.GetPicture(new FileManager.PictureDefinition(Book.PictureId, FileManager.PictureSize._80x80));
+			(_, var picture) = PictureStorage.GetPicture(new PictureDefinition(Book.PictureId, PictureSize._80x80));
 			this.coverPb.Image = Dinah.Core.Drawing.ImageReader.ToImage(picture);
 
 			var t = @$"

LibationWinForms/Dialogs/DirectoryOrCustomSelectControl.cs

@@ -1,8 +1,8 @@
-using FileManager;
-using System;
+using System;
 using System.Linq;
 using System.Collections.Generic;
 using System.Windows.Forms;
+using LibationFileManager;
 
 namespace LibationWinForms.Dialogs
 {

LibationWinForms/Dialogs/DirectorySelectControl.cs

@@ -1,9 +1,9 @@
-using Dinah.Core;
-using FileManager;
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Windows.Forms;
+using Dinah.Core;
+using LibationFileManager;
 
 namespace LibationWinForms.Dialogs
 {

LibationWinForms/Dialogs/EditQuickFilters.cs

@@ -1,7 +1,7 @@
-using FileManager;
-using System;
+using System;
 using System.Linq;
 using System.Windows.Forms;
+using LibationFileManager;
 
 namespace LibationWinForms.Dialogs
 {

LibationWinForms/Dialogs/EditTemplateDialog.Designer.cs

@@ -0,0 +1,197 @@
+namespace LibationWinForms.Dialogs
+{
+	partial class EditTemplateDialog
+	{
+		/// <summary>
+		/// Required designer variable.
+		/// </summary>
+		private System.ComponentModel.IContainer components = null;
+
+		/// <summary>
+		/// Clean up any resources being used.
+		/// </summary>
+		/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+		protected override void Dispose(bool disposing)
+		{
+			if (disposing && (components != null))
+			{
+				components.Dispose();
+			}
+			base.Dispose(disposing);
+		}
+
+		#region Windows Form Designer generated code
+
+		/// <summary>
+		/// Required method for Designer support - do not modify
+		/// the contents of this method with the code editor.
+		/// </summary>
+		private void InitializeComponent()
+		{
+			this.saveBtn = new System.Windows.Forms.Button();
+			this.cancelBtn = new System.Windows.Forms.Button();
+			this.templateTb = new System.Windows.Forms.TextBox();
+			this.templateLbl = new System.Windows.Forms.Label();
+			this.resetToDefaultBtn = new System.Windows.Forms.Button();
+			this.listView1 = new System.Windows.Forms.ListView();
+			this.columnHeader1 = new System.Windows.Forms.ColumnHeader();
+			this.columnHeader2 = new System.Windows.Forms.ColumnHeader();
+			this.richTextBox1 = new System.Windows.Forms.RichTextBox();
+			this.warningsLbl = new System.Windows.Forms.Label();
+			this.exampleLbl = new System.Windows.Forms.Label();
+			this.SuspendLayout();
+			// 
+			// saveBtn
+			// 
+			this.saveBtn.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
+			this.saveBtn.Location = new System.Drawing.Point(714, 345);
+			this.saveBtn.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
+			this.saveBtn.Name = "saveBtn";
+			this.saveBtn.Size = new System.Drawing.Size(88, 27);
+			this.saveBtn.TabIndex = 98;
+			this.saveBtn.Text = "Save";
+			this.saveBtn.UseVisualStyleBackColor = true;
+			this.saveBtn.Click += new System.EventHandler(this.saveBtn_Click);
+			// 
+			// cancelBtn
+			// 
+			this.cancelBtn.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
+			this.cancelBtn.DialogResult = System.Windows.Forms.DialogResult.Cancel;
+			this.cancelBtn.Location = new System.Drawing.Point(832, 345);
+			this.cancelBtn.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
+			this.cancelBtn.Name = "cancelBtn";
+			this.cancelBtn.Size = new System.Drawing.Size(88, 27);
+			this.cancelBtn.TabIndex = 99;
+			this.cancelBtn.Text = "Cancel";
+			this.cancelBtn.UseVisualStyleBackColor = true;
+			this.cancelBtn.Click += new System.EventHandler(this.cancelBtn_Click);
+			// 
+			// templateTb
+			// 
+			this.templateTb.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+			this.templateTb.Location = new System.Drawing.Point(12, 27);
+			this.templateTb.Name = "templateTb";
+			this.templateTb.Size = new System.Drawing.Size(779, 23);
+			this.templateTb.TabIndex = 1;
+			this.templateTb.TextChanged += new System.EventHandler(this.templateTb_TextChanged);
+			// 
+			// templateLbl
+			// 
+			this.templateLbl.AutoSize = true;
+			this.templateLbl.Location = new System.Drawing.Point(12, 9);
+			this.templateLbl.Name = "templateLbl";
+			this.templateLbl.Size = new System.Drawing.Size(89, 15);
+			this.templateLbl.TabIndex = 0;
+			this.templateLbl.Text = "[template desc]";
+			// 
+			// resetToDefaultBtn
+			// 
+			this.resetToDefaultBtn.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
+			this.resetToDefaultBtn.Location = new System.Drawing.Point(797, 26);
+			this.resetToDefaultBtn.Name = "resetToDefaultBtn";
+			this.resetToDefaultBtn.Size = new System.Drawing.Size(124, 23);
+			this.resetToDefaultBtn.TabIndex = 2;
+			this.resetToDefaultBtn.Text = "Reset to default";
+			this.resetToDefaultBtn.UseVisualStyleBackColor = true;
+			this.resetToDefaultBtn.Click += new System.EventHandler(this.resetToDefaultBtn_Click);
+			// 
+			// listView1
+			// 
+			this.listView1.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
+            | System.Windows.Forms.AnchorStyles.Left)));
+			this.listView1.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] {
+            this.columnHeader1,
+            this.columnHeader2});
+			this.listView1.HideSelection = false;
+			this.listView1.Location = new System.Drawing.Point(12, 56);
+			this.listView1.Name = "listView1";
+			this.listView1.Size = new System.Drawing.Size(328, 283);
+			this.listView1.TabIndex = 3;
+			this.listView1.UseCompatibleStateImageBehavior = false;
+			this.listView1.View = System.Windows.Forms.View.Details;
+			// 
+			// columnHeader1
+			// 
+			this.columnHeader1.Text = "Tag";
+			this.columnHeader1.Width = 137;
+			// 
+			// columnHeader2
+			// 
+			this.columnHeader2.Text = "Description";
+			this.columnHeader2.Width = 170;
+			// 
+			// richTextBox1
+			// 
+			this.richTextBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
+            | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+			this.richTextBox1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
+			this.richTextBox1.Location = new System.Drawing.Point(346, 74);
+			this.richTextBox1.Name = "richTextBox1";
+			this.richTextBox1.ReadOnly = true;
+			this.richTextBox1.Size = new System.Drawing.Size(574, 185);
+			this.richTextBox1.TabIndex = 5;
+			this.richTextBox1.Text = "";
+			// 
+			// warningsLbl
+			// 
+			this.warningsLbl.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
+			this.warningsLbl.Font = new System.Drawing.Font("Segoe UI", 9F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point);
+			this.warningsLbl.ForeColor = System.Drawing.Color.Firebrick;
+			this.warningsLbl.Location = new System.Drawing.Point(346, 262);
+			this.warningsLbl.Name = "warningsLbl";
+			this.warningsLbl.Size = new System.Drawing.Size(574, 77);
+			this.warningsLbl.TabIndex = 6;
+			this.warningsLbl.Text = "[warnings]";
+			// 
+			// exampleLbl
+			// 
+			this.exampleLbl.AutoSize = true;
+			this.exampleLbl.Location = new System.Drawing.Point(346, 56);
+			this.exampleLbl.Name = "exampleLbl";
+			this.exampleLbl.Size = new System.Drawing.Size(55, 15);
+			this.exampleLbl.TabIndex = 4;
+			this.exampleLbl.Text = "Example:";
+			// 
+			// EditTemplateDialog
+			// 
+			this.AcceptButton = this.saveBtn;
+			this.AutoScaleDimensions = new System.Drawing.SizeF(7F, 15F);
+			this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+			this.CancelButton = this.cancelBtn;
+			this.ClientSize = new System.Drawing.Size(933, 388);
+			this.Controls.Add(this.exampleLbl);
+			this.Controls.Add(this.warningsLbl);
+			this.Controls.Add(this.richTextBox1);
+			this.Controls.Add(this.listView1);
+			this.Controls.Add(this.resetToDefaultBtn);
+			this.Controls.Add(this.templateLbl);
+			this.Controls.Add(this.templateTb);
+			this.Controls.Add(this.cancelBtn);
+			this.Controls.Add(this.saveBtn);
+			this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedToolWindow;
+			this.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
+			this.Name = "EditTemplateDialog";
+			this.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
+			this.Text = "Edit Template";
+			this.Load += new System.EventHandler(this.EditTemplateDialog_Load);
+			this.ResumeLayout(false);
+			this.PerformLayout();
+
+		}
+
+		#endregion
+		private System.Windows.Forms.Button saveBtn;
+		private System.Windows.Forms.Button cancelBtn;
+		private System.Windows.Forms.TextBox templateTb;
+		private System.Windows.Forms.Label templateLbl;
+		private System.Windows.Forms.Button resetToDefaultBtn;
+		private System.Windows.Forms.ListView listView1;
+		private System.Windows.Forms.ColumnHeader columnHeader1;
+		private System.Windows.Forms.ColumnHeader columnHeader2;
+		private System.Windows.Forms.RichTextBox richTextBox1;
+		private System.Windows.Forms.Label warningsLbl;
+		private System.Windows.Forms.Label exampleLbl;
+	}
+}

LibationWinForms/Dialogs/EditTemplateDialog.cs

@@ -0,0 +1,173 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.IO;
+using System.Windows.Forms;
+using Dinah.Core;
+using LibationFileManager;
+
+namespace LibationWinForms.Dialogs
+{
+	public partial class EditTemplateDialog : Form
+	{
+		// final value. post-validity check
+		public string TemplateText { get; private set; }
+
+		// hold the work-in-progress value. not guaranteed to be valid
+		private string _workingTemplateText;
+		private string workingTemplateText
+		{
+			get => _workingTemplateText;
+			set => _workingTemplateText = template.Sanitize(value);
+		}
+
+		private void resetTextBox(string value) => this.templateTb.Text = workingTemplateText = value;
+
+		private Configuration config { get; } = Configuration.Instance;
+
+		private Templates template { get; }
+		private string inputTemplateText { get; }
+
+		public EditTemplateDialog() => InitializeComponent();
+		public EditTemplateDialog(Templates template, string inputTemplateText) : this()
+		{
+			this.template = ArgumentValidator.EnsureNotNull(template, nameof(template));
+			this.inputTemplateText = inputTemplateText ?? "";
+		}
+
+		private void EditTemplateDialog_Load(object sender, EventArgs e)
+		{
+			if (this.DesignMode)
+				return;
+
+			if (template is null)
+			{
+				MessageBoxAlertAdmin.Show($"Programming error. {nameof(EditTemplateDialog)} was not created correctly", "Edit template error", new NullReferenceException($"{nameof(template)} is null"));
+				return;
+			}
+
+			warningsLbl.Text = "";
+
+			this.Text = $"Edit {template.Name}";
+
+			this.templateLbl.Text = template.Description;
+			resetTextBox(inputTemplateText);
+
+			// populate list view
+			foreach (var tag in template.GetTemplateTags())
+				listView1.Items.Add(new ListViewItem(new[] { $"<{tag.TagName}>", tag.Description }));
+		}
+
+		private void resetToDefaultBtn_Click(object sender, EventArgs e) => resetTextBox(template.DefaultTemplate);
+
+		private void templateTb_TextChanged(object sender, EventArgs e)
+		{
+			workingTemplateText = templateTb.Text;
+
+			var isFolder = template == Templates.Folder;
+
+			var libraryBookDto = new LibraryBookDto
+			{
+				Account = "my account",
+				AudibleProductId = "123456789",
+				Title = "A Study in Scarlet: A Sherlock Holmes Novel",
+				Locale = "us",
+				Authors = new List<string> { "Arthur Conan Doyle", "Stephen Fry - introductions" },
+				Narrators = new List<string> { "Stephen Fry" },
+				SeriesName = "Sherlock Holmes",
+				SeriesNumber = "1"
+			};
+			var chapterName = "A Flight for Life";
+			var chapterNumber = 4;
+			var chaptersTotal = 10;
+
+			var books = config.Books;
+			var folder = Templates.Folder.GetPortionFilename(
+				libraryBookDto,
+				isFolder ? workingTemplateText : config.FolderTemplate);
+			var file
+				= template == Templates.ChapterFile
+				? Templates.ChapterFile.GetPortionFilename(
+					libraryBookDto,
+					workingTemplateText,
+					new() { OutputFileName = "", PartsPosition = chapterNumber, PartsTotal = chaptersTotal, Title = chapterName },
+					"")
+				: Templates.File.GetPortionFilename(
+					libraryBookDto,
+					isFolder ? config.FileTemplate : workingTemplateText);
+			var ext = config.DecryptToLossy ? "mp3" : "m4b";
+
+			const char ZERO_WIDTH_SPACE = '\u200B';
+			var sing = $"{Path.DirectorySeparatorChar}";
+
+			// result: can wrap long paths. eg:
+			// |-- LINE WRAP BOUNDARIES --|
+			// \books\author with a very     <= normal line break on space between words
+			// long name\narrator narrator   
+			// \title                        <= line break on the zero-with space we added before slashes
+			string slashWrap(string val) => val.Replace(sing, $"{ZERO_WIDTH_SPACE}{sing}");
+
+			warningsLbl.Text
+				= !template.HasWarnings(workingTemplateText)
+				? ""
+				: "Warning:\r\n" +
+					template
+					.GetWarnings(workingTemplateText)
+					.Select(err => $"- {err}")
+					.Aggregate((a, b) => $"{a}\r\n{b}");
+
+			var bold = new System.Drawing.Font(richTextBox1.Font, System.Drawing.FontStyle.Bold);
+			var reg = new System.Drawing.Font(richTextBox1.Font, System.Drawing.FontStyle.Regular);
+
+			richTextBox1.Clear();
+			richTextBox1.SelectionFont = reg;
+
+			richTextBox1.AppendText(slashWrap(books));
+			richTextBox1.AppendText(sing);
+
+			if (isFolder)
+				richTextBox1.SelectionFont = bold;
+
+			richTextBox1.AppendText(slashWrap(folder));
+
+			if (isFolder)
+				richTextBox1.SelectionFont = reg;
+
+			richTextBox1.AppendText(sing);
+
+			if (!isFolder)
+				richTextBox1.SelectionFont = bold;
+
+			richTextBox1.AppendText(file);
+
+			if (!isFolder)
+				richTextBox1.SelectionFont = reg;
+
+			richTextBox1.AppendText($".{ext}");
+		}
+
+		private void saveBtn_Click(object sender, EventArgs e)
+		{
+			if (!template.IsValid(workingTemplateText))
+			{
+				var errors = template
+					.GetErrors(workingTemplateText)
+					.Select(err => $"- {err}")
+					.Aggregate((a, b) => $"{a}\r\n{b}");
+				MessageBox.Show($"This template text is not valid. Errors:\r\n{errors}", "Invalid", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				return;
+			}
+
+			TemplateText = workingTemplateText;
+
+			this.DialogResult = DialogResult.OK;
+			this.Close();
+		}
+
+		private void cancelBtn_Click(object sender, EventArgs e)
+		{
+			this.DialogResult = DialogResult.Cancel;
+			this.Close();
+		}
+	}
+}

LibationWinForms/Dialogs/EditTemplateDialog.resx

@@ -0,0 +1,60 @@
+<root>
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+</root>