Add warnings for inaccessable InProgress directory (#1446)

Source/AaxDecrypter/UnencryptedAudiobookDownloader.cs

@@ -1,6 +1,6 @@
 using FileManager;
 using System.Threading.Tasks;
-
+#nullable enable
 namespace AaxDecrypter
 {
 	public class UnencryptedAudiobookDownloader : AudiobookDownloadBase

Source/AppScaffolding/LibationScaffolding.cs

@@ -243,6 +243,7 @@ namespace AppScaffolding
             //Log.Logger.Here().Debug("Begin Libation. Debug with line numbers");
         }
 
+#nullable enable
 		private static void logStartupState(Configuration config)
 		{
 #if DEBUG
@@ -256,9 +257,11 @@ namespace AppScaffolding
 			// begin logging session with a form feed
 			Log.Logger.Information("\r\n\f");
 
-			static int fileCount(FileManager.LongPath longPath)
+			static int fileCount(FileManager.LongPath? longPath)
             {
-                try { return FileManager.FileUtility.SaferEnumerateFiles(longPath).Count(); }
+				if (longPath is null)
+					return -1;
+				try { return FileManager.FileUtility.SaferEnumerateFiles(longPath).Count(); }
                 catch { return -1; }
             }
 
@@ -298,8 +301,8 @@ namespace AppScaffolding
 			if (InteropFactory.InteropFunctionsType is null)
                 Serilog.Log.Logger.Warning("WARNING: OSInteropProxy.InteropFunctionsType is null");
         }
-
-        private static void wireUpSystemEvents(Configuration configuration)
+#nullable restore
+		private static void wireUpSystemEvents(Configuration configuration)
 		{
 			LibraryCommands.LibrarySizeChanged += (object _, List<DataLayer.LibraryBook> libraryBooks)
 				=> SearchEngineCommands.FullReIndex(libraryBooks);

Source/FileLiberator/DownloadDecryptBook.cs

@@ -129,20 +129,21 @@ namespace FileLiberator
 
 		private async Task<AudiobookDecryptResult> DownloadAudiobookAsync(AudibleApi.Api api, DownloadOptions dlOptions, CancellationToken cancellationToken)
 		{
-			var outpoutDir = AudibleFileStorage.DecryptInProgressDirectory;
-			var cacheDir = AudibleFileStorage.DownloadsInProgressDirectory;
+			//Directories are validated prior to beginning download/decrypt
+			var outputDir = AudibleFileStorage.DecryptInProgressDirectory!;
+			var cacheDir = AudibleFileStorage.DownloadsInProgressDirectory!;
 			var result = new AudiobookDecryptResult(false, [], []);
 
 			try
 			{
 				if (dlOptions.DrmType is not DrmType.Adrm and not DrmType.Widevine)
-					abDownloader = new UnencryptedAudiobookDownloader(outpoutDir, cacheDir, dlOptions);
+					abDownloader = new UnencryptedAudiobookDownloader(outputDir, cacheDir, dlOptions);
 				else
 				{
 					AaxcDownloadConvertBase converter
 						= dlOptions.Config.SplitFilesByChapter && dlOptions.ChapterInfo.Count > 1 ?
-						new AaxcDownloadMultiConverter(outpoutDir, cacheDir, dlOptions) :
-						new AaxcDownloadSingleConverter(outpoutDir, cacheDir, dlOptions);
+						new AaxcDownloadMultiConverter(outputDir, cacheDir, dlOptions) :
+						new AaxcDownloadSingleConverter(outputDir, cacheDir, dlOptions);
 
 					if (dlOptions.Config.AllowLibationFixup)
 						converter.RetrievedMetadata += Converter_RetrievedMetadata;
@@ -176,7 +177,7 @@ namespace FileLiberator
 
 			void AbDownloader_TempFileCreated(object? sender, TempFile e)
 			{
-				if (Path.GetDirectoryName(e.FilePath) == outpoutDir)
+				if (Path.GetDirectoryName(e.FilePath) == outputDir)
 				{
 					result.ResultFiles.Add(e);
 				}

Source/LibationFileManager/AudibleFileStorage.cs

@@ -19,8 +19,32 @@ namespace LibationFileManager
 		protected abstract List<LongPath> GetFilePathsCustom(string productId);
 
 		#region static
-		public static LongPath DownloadsInProgressDirectory => Directory.CreateDirectory(Path.Combine(Configuration.Instance.InProgress, "DownloadsInProgress")).FullName;
-		public static LongPath DecryptInProgressDirectory => Directory.CreateDirectory(Path.Combine(Configuration.Instance.InProgress, "DecryptInProgress")).FullName;
+
+		/*
+		 * Operations like LibraryCommands.GetCounts() hit the file system hard.
+		 * Since failing to create a directory and exception handling is expensive,
+		 * only retry creating InProgress subdirectories every RetryInProgressInterval.
+		 */
+		private static DateTime lastInProgressFail;
+		private static readonly TimeSpan RetryInProgressInterval = TimeSpan.FromSeconds(2);
+
+		private static DirectoryInfo? CreateInProgressDirectory(string subDirectory)
+		{
+			try
+			{
+				return (DateTime.UtcNow - lastInProgressFail) < RetryInProgressInterval ? null
+					: new DirectoryInfo(Configuration.Instance.InProgress).CreateSubdirectoryEx(subDirectory);
+			}
+			catch (Exception ex)
+			{
+				Serilog.Log.Error(ex, "Error creating subdirectory in {@InProgress}", Configuration.Instance.InProgress);
+				lastInProgressFail = DateTime.UtcNow;
+				return null;
+			}
+		}
+
+		public static LongPath? DownloadsInProgressDirectory => CreateInProgressDirectory("DownloadsInProgress")?.FullName;
+		public static LongPath? DecryptInProgressDirectory => CreateInProgressDirectory("DecryptInProgress")?.FullName;
 
 		static AudibleFileStorage()
 		{
@@ -28,7 +52,9 @@ namespace LibationFileManager
 			//Do not clean DownloadsInProgressDirectory. Those files are resumable.
 			try
             {
-                foreach (var tempFile in FileUtility.SaferEnumerateFiles(DecryptInProgressDirectory))
+				if (DecryptInProgressDirectory is not LongPath decryptDir)
+					return;
+                foreach (var tempFile in FileUtility.SaferEnumerateFiles(decryptDir))
                     FileUtility.SaferDelete(tempFile);
             }
             catch (Exception ex)
@@ -114,9 +140,12 @@ namespace LibationFileManager
 
 		protected override List<LongPath> GetFilePathsCustom(string productId)
 		{
+			if (DownloadsInProgressDirectory is not LongPath dlFolder)
+				return [];
+
 			var regex = GetBookSearchRegex(productId);
 			return FileUtility
-				.SaferEnumerateFiles(DownloadsInProgressDirectory, "*.*", SearchOption.AllDirectories)
+				.SaferEnumerateFiles(dlFolder, "*.*", SearchOption.AllDirectories)
 				.Where(s => regex.IsMatch(s)).ToList();
 		}
 

Source/LibationUiBase/ProcessQueue/ProcessQueueViewModel.cs

@@ -184,6 +184,26 @@ public class ProcessQueueViewModel : ReactiveObject
 				MessageBoxIcon.Error);
 			return false;
 		}
+		else if (AudibleFileStorage.DownloadsInProgressDirectory is null)
+		{
+			Serilog.Log.Logger.Error("Failed to create DownloadsInProgressDirectory in {@InProgress}", Configuration.Instance.InProgress);
+			MessageBoxBase.Show(
+				$"Libation was unable to create the \"Downloads In Progress\" folder in:\n{Configuration.Instance.InProgress}\n\nPlease change the In Progress location in the settings menu.",
+				"Failed to Create Downloads In Progress Directory",
+				MessageBoxButtons.OK,
+				MessageBoxIcon.Error);
+			return false;
+		}
+		else if (AudibleFileStorage.DecryptInProgressDirectory is null)
+		{
+			Serilog.Log.Logger.Error("Failed to create DecryptInProgressDirectory in {@InProgress}", Configuration.Instance.InProgress);
+			MessageBoxBase.Show(
+				$"Libation was unable to create the \"Decrypt In Progress\" folder in:\n{Configuration.Instance.InProgress}\n\nPlease change the In Progress location in the settings menu.",
+				"Failed to Create Decrypt In Progress Directory",
+				MessageBoxButtons.OK,
+				MessageBoxIcon.Error);
+			return false;
+		}
 
 		return true;
 	}