Bugfix: decrypt file conflict

AaxDecrypter/UNTESTED/AaxToM4bConverter.cs

@@ -72,8 +72,9 @@ namespace AaxDecrypter
         }
         private AaxToM4bConverter(string inputFile, string decryptKey)
         {
-            if (string.IsNullOrWhiteSpace(inputFile)) throw new ArgumentNullException(nameof(inputFile), "Input file may not be null or whitespace");
-            if (!File.Exists(inputFile)) throw new ArgumentNullException(nameof(inputFile), "File does not exist");
+			ArgumentValidator.EnsureNotNullOrWhiteSpace(inputFile, nameof(inputFile));
+            if (!File.Exists(inputFile))
+                throw new ArgumentNullException(nameof(inputFile), "File does not exist");
 
             steps = new StepSequence
             {
@@ -89,22 +90,24 @@ namespace AaxDecrypter
                 ["End: Create Nfo"] = End_CreateNfo
             };
 
-            this.inputFileName = inputFile;
+            inputFileName = inputFile;
             this.decryptKey = decryptKey;
         }
 
         private async Task prelimProcessing()
         {
-            this.tags = new Tags(this.inputFileName);
-            this.encodingInfo = new EncodingInfo(this.inputFileName);
-            this.chapters = new Chapters(this.inputFileName, this.tags.duration.TotalSeconds);
+            tags = new Tags(inputFileName);
+            encodingInfo = new EncodingInfo(inputFileName);
+            chapters = new Chapters(inputFileName, tags.duration.TotalSeconds);
 
             var defaultFilename = Path.Combine(
-                Path.GetDirectoryName(this.inputFileName),
-                getASCIITag(this.tags.author),
-                getASCIITag(this.tags.title) + ".m4b"
+                Path.GetDirectoryName(inputFileName),
+                getASCIITag(tags.author),
+                getASCIITag(tags.title) + ".m4b"
                 );
-            SetOutputFilename(defaultFilename);
+
+			// set default name
+			SetOutputFilename(defaultFilename);
 
             await Task.Run(() => saveCover(inputFileName));
         }
@@ -118,7 +121,7 @@ namespace AaxDecrypter
         private void saveCover(string aaxFile)
         {
 			using var file = TagLib.File.Create(aaxFile, "audio/mp4", TagLib.ReadStyle.Average);
-			this.coverBytes = file.Tag.Pictures[0].Data.Data;
+			coverBytes = file.Tag.Pictures[0].Data.Data;
 		}
 
         private void printPrelim()
@@ -156,21 +159,24 @@ namespace AaxDecrypter
 
         public void SetOutputFilename(string outFileName)
         {
-            this.outputFileName = outFileName;
+            outputFileName = outFileName;
 
-            if (Path.GetExtension(this.outputFileName) != ".m4b")
-                this.outputFileName = outputFileWithNewExt(".m4b");
+            if (Path.GetExtension(outputFileName) != ".m4b")
+                outputFileName = outputFileWithNewExt(".m4b");
 
-            this.outDir = Path.GetDirectoryName(this.outputFileName);
+			if (File.Exists(outputFileName))
+				File.Delete(outputFileName);
+
+            outDir = Path.GetDirectoryName(outputFileName);
         }
 
         private string outputFileWithNewExt(string extension)
-            => Path.Combine(this.outDir, Path.GetFileNameWithoutExtension(this.outputFileName) + '.' + extension.Trim('.'));
+            => Path.Combine(outDir, Path.GetFileNameWithoutExtension(outputFileName) + '.' + extension.Trim('.'));
 
         public bool Step1_CreateDir()
         {
-            ProcessRunner.WorkingDir = this.outDir;
-            Directory.CreateDirectory(this.outDir);
+            ProcessRunner.WorkingDir = outDir;
+            Directory.CreateDirectory(outDir);
             return true;
         }
 
@@ -178,7 +184,7 @@ namespace AaxDecrypter
         {
             DecryptProgressUpdate?.Invoke(this, 0);
 
-            var tempRipFile = Path.Combine(this.outDir, "funny.aac");
+            var tempRipFile = Path.Combine(outDir, "funny.aac");
 
             var fail = "WARNING-Decrypt failure. ";
 
@@ -193,7 +199,7 @@ namespace AaxDecrypter
                 if (returnCode == -99)
                 {
                     Console.WriteLine($"{fail}Incorrect decrypt key: {decryptKey}");
-                    this.decryptKey = null;
+                    decryptKey = null;
                     returnCode = getKey_decrypt(tempRipFile);
                 }
             }
@@ -232,7 +238,7 @@ namespace AaxDecrypter
 
             Console.WriteLine("Cracking activation bytes");
             var activation_bytes = BytesCracker.GetActivationBytes(checksum);
-            this.decryptKey = activation_bytes;
+            decryptKey = activation_bytes;
             Console.WriteLine("Activation bytes cracked. Decrypt key: " + activation_bytes);
         }
 
@@ -243,10 +249,10 @@ namespace AaxDecrypter
             Console.WriteLine("Decrypting with key " + decryptKey);
 
             var returnCode = 100;
-            var thread = new Thread(() => returnCode = this.ngDecrypt());
+            var thread = new Thread(() => returnCode = ngDecrypt());
             thread.Start();
 
-            double fileLen = new FileInfo(this.inputFileName).Length;
+            double fileLen = new FileInfo(inputFileName).Length;
             while (thread.IsAlive && returnCode == 100)
             {
                 Thread.Sleep(500);
@@ -266,7 +272,7 @@ namespace AaxDecrypter
             var info = new ProcessStartInfo
             {
                 FileName = DecryptSupportLibraries.mp4trackdumpPath,
-                Arguments = "-c " + this.encodingInfo.channels + " -r " + this.encodingInfo.sampleRate + " \"" + this.inputFileName + "\""
+                Arguments = "-c " + encodingInfo.channels + " -r " + encodingInfo.sampleRate + " \"" + inputFileName + "\""
             };
             info.EnvironmentVariables["VARIABLE"] = decryptKey;
 
@@ -279,21 +285,22 @@ namespace AaxDecrypter
             return exitCode;
         }
 
-        // temp file names for steps 3, 4, 5
-        string tempChapsPath => Path.Combine(this.outDir, "tempChaps.mp4");
+		// temp file names for steps 3, 4, 5
+        string tempChapsGuid { get; } = Guid.NewGuid().ToString().ToUpper().Replace("-", "");
+        string tempChapsPath => Path.Combine(outDir, $"tempChaps_{tempChapsGuid}.mp4");
         string mp4_file => outputFileWithNewExt(".mp4");
         string ff_txt_file => mp4_file + ".ff.txt";
 
         public bool Step3_Chapterize()
         {
             string str1 = "";
-            if (this.chapters.FirstChapterStart != 0.0)
+            if (chapters.FirstChapterStart != 0.0)
             {
-                str1 = " -ss " + this.chapters.FirstChapterStart.ToString("0.000", CultureInfo.InvariantCulture) + " -t " + (this.chapters.LastChapterStart - 1.0).ToString("0.000", CultureInfo.InvariantCulture) + " ";
+                str1 = " -ss " + chapters.FirstChapterStart.ToString("0.000", CultureInfo.InvariantCulture) + " -t " + (chapters.LastChapterStart - 1.0).ToString("0.000", CultureInfo.InvariantCulture) + " ";
             }
 
-            string ffmpegTags = this.tags.GenerateFfmpegTags();
-            string ffmpegChapters = this.chapters.GenerateFfmpegChapters();
+            string ffmpegTags = tags.GenerateFfmpegTags();
+            string ffmpegChapters = chapters.GenerateFfmpegChapters();
             File.WriteAllText(ff_txt_file, ffmpegTags + ffmpegChapters);
 
             var tagAndChapterInfo = new ProcessStartInfo
@@ -309,8 +316,8 @@ namespace AaxDecrypter
         public bool Step4_InsertCoverArt()
         {
             // save cover image as temp file
-            var coverPath = Path.Combine(this.outDir, "cover-" + Guid.NewGuid() + ".jpg");
-            FileExt.CreateFile(coverPath, this.coverBytes);
+            var coverPath = Path.Combine(outDir, "cover-" + Guid.NewGuid() + ".jpg");
+            FileExt.CreateFile(coverPath, coverBytes);
 
             var insertCoverArtInfo = new ProcessStartInfo
             {
@@ -329,26 +336,26 @@ namespace AaxDecrypter
         {
             FileExt.SafeDelete(mp4_file);
             FileExt.SafeDelete(ff_txt_file);
-            FileExt.SafeMove(tempChapsPath, this.outputFileName);
+            FileExt.SafeMove(tempChapsPath, outputFileName);
 
             return true;
         }
 
         public bool Step6_AddTags()
         {
-            this.tags.AddAppleTags(this.outputFileName);
+            tags.AddAppleTags(outputFileName);
             return true;
         }
 
         public bool End_CreateCue()
         {
-            File.WriteAllText(outputFileWithNewExt(".cue"), this.chapters.GetCuefromChapters(Path.GetFileName(this.outputFileName)));
+            File.WriteAllText(outputFileWithNewExt(".cue"), chapters.GetCuefromChapters(Path.GetFileName(outputFileName)));
             return true;
         }
 
         public bool End_CreateNfo()
         {
-            File.WriteAllText(outputFileWithNewExt(".nfo"), NFO.CreateNfoContents(AppName, this.tags, this.encodingInfo, this.chapters));
+            File.WriteAllText(outputFileWithNewExt(".nfo"), NFO.CreateNfoContents(AppName, tags, encodingInfo, chapters));
             return true;
         }
     }

AaxDecrypter/UNTESTED/Tags.cs

@@ -28,7 +28,7 @@ namespace AaxDecrypter
 			using TagLib.File tagLibFile = TagLib.File.Create(file, "audio/mp4", ReadStyle.Average);
 			this.title = tagLibFile.Tag.Title.Replace(" (Unabridged)", "");
 			this.album = tagLibFile.Tag.Album.Replace(" (Unabridged)", "");
-			this.author = tagLibFile.Tag.FirstPerformer;
+			this.author = tagLibFile.Tag.FirstPerformer ?? "[unknown]";
 			this.year = tagLibFile.Tag.Year.ToString();
 			this.comments = tagLibFile.Tag.Comment;
 			this.duration = tagLibFile.Properties.Duration;

DataLayer/UNTESTED/EfClasses/Book.cs

@@ -123,16 +123,10 @@ namespace DataLayer
             ArgumentValidator.EnsureEnumerableNotNullOrEmpty(newContributors, nameof(newContributors));
 
             // the edge cases of doing local-loaded vs remote-only got weird. just load it
-            if (_contributorsLink == null)
-            {
-                ArgumentValidator.EnsureNotNull(context, nameof(context));
-                if (!context.Entry(this).IsKeySet)
-                    throw new InvalidOperationException("Could not add contributors");
+            if (_contributorsLink is null)
+				getEntry(context).Collection(s => s.ContributorsLink).Load();
 
-                context.Entry(this).Collection(s => s.ContributorsLink).Load();
-            }
-
-            var roleContributions = getContributions(role);
+			var roleContributions = getContributions(role);
             var isIdentical = roleContributions.Select(c => c.Contributor).SequenceEqual(newContributors);
             if (isIdentical)
                 return;
@@ -140,7 +134,8 @@ namespace DataLayer
             _contributorsLink.RemoveWhere(bc => bc.Role == role);
             addNewContributors(newContributors, role);
         }
-        private void addNewContributors(IEnumerable<Contributor> newContributors, Role role)
+
+		private void addNewContributors(IEnumerable<Contributor> newContributors, Role role)
         {
             byte order = 0;
             var newContributionsEnum = newContributors.Select(c => new BookContributor(this, c, role, order++));
@@ -155,6 +150,18 @@ namespace DataLayer
                 .ToList();
         #endregion
 
+		private Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry<Book> getEntry(DbContext context)
+		{
+			ArgumentValidator.EnsureNotNull(context, nameof(context));
+
+			var entry = context.Entry(this);
+
+			if (!entry.IsKeySet)
+				throw new InvalidOperationException("Could not load a valid Book from database");
+
+			return entry;
+		}
+
         #region series
         private HashSet<SeriesBook> _seriesLink;
         public IEnumerable<SeriesBook> SeriesLink => _seriesLink?.ToList();
@@ -186,16 +193,10 @@ namespace DataLayer
 
             // our add() is conditional upon what's already included in the collection.
             // therefore if not loaded, a trip is required. might as well just load it
-            if (_seriesLink == null)
-            {
-                ArgumentValidator.EnsureNotNull(context, nameof(context));
-                if (!context.Entry(this).IsKeySet)
-                    throw new InvalidOperationException("Could not add series");
+            if (_seriesLink is null)
+				getEntry(context).Collection(s => s.SeriesLink).Load();
 
-                context.Entry(this).Collection(s => s.SeriesLink).Load();
-            }
-
-            var singleSeriesBook = _seriesLink.SingleOrDefault(sb => sb.Series == series);
+			var singleSeriesBook = _seriesLink.SingleOrDefault(sb => sb.Series == series);
             if (singleSeriesBook == null)
                 _seriesLink.Add(new SeriesBook(series, this, index));
             else
@@ -211,8 +212,7 @@ namespace DataLayer
         public void AddSupplementDownloadUrl(string url)
         {
             // supplements are owned by Book, so no need to Load():
-            // OwnsMany: "Can only ever appear on navigation properties of other entity types.
-            //  Are automatically loaded, and can only be tracked by a DbContext alongside their owner."
+            //  Are automatically loaded, and can only be tracked by a DbContext alongside their owner.
 
             ArgumentValidator.EnsureNotNullOrWhiteSpace(url, nameof(url));
 
@@ -232,19 +232,12 @@ namespace DataLayer
         }
 
         public void UpdateCategory(Category category, DbContext context = null)
-        {
-            // since category is never null, nullity means it hasn't been loaded. non null means we're correctly loaded. just overwrite
-            if (Category != null)
-            {
-                Category = category;
-                return;
-            }
+		{
+			// since category is never null, nullity means it hasn't been loaded
+			if (Category is null)
+				getEntry(context).Reference(s => s.Category).Load();
 
-            if (context == null)
-                throw new Exception("need context");
-            
-            context.Entry(this).Reference(s => s.Category).Load();
-            Category = category;
+			Category = category;
         }
 
 		public override string ToString() => $"[{AudibleProductId}] {Title}";

DataLayer/UNTESTED/LibationContext.cs

@@ -64,7 +64,8 @@ namespace DataLayer
 				.Entity<Contributor>()
 				.HasData(Contributor.GetEmpty());
 
-            // views are now supported via "query types" (instead of "entity types"): https://docs.microsoft.com/en-us/ef/core/modeling/query-types
-        }
-    }
+			// views are now supported via "keyless entity types" (instead of "entity types" or the prev "query types"):
+			// https://docs.microsoft.com/en-us/ef/core/modeling/keyless-entity-types
+		}
+	}
 }

DataLayer/UNTESTED/TagPersistenceInterceptor.cs

@@ -4,7 +4,6 @@ using System.Linq;
 using Dinah.Core.Collections.Generic;
 using Dinah.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore;
-using Microsoft.EntityFrameworkCore.ChangeTracking;
 
 namespace DataLayer
 {
@@ -14,25 +13,18 @@ namespace DataLayer
 
         public void Executing(DbContext context)
 		{
-			// persist tags:
-			var modifiedEntities = context
+			var tagsCollection
+				= context
 				.ChangeTracker
 				.Entries()
-				.Where(p => p.State.In(EntityState.Modified, EntityState.Added))
-				.ToList();
-
-			persistTags(modifiedEntities);
-		}
-
-		private static void persistTags(List<EntityEntry> modifiedEntities)
-		{
-			var tagSets = modifiedEntities
+				.Where(e => e.State.In(EntityState.Modified, EntityState.Added))
 				.Select(e => e.Entity as UserDefinedItem)
-				// filter by null but NOT by blank. blank is the valid way to show the absence of tags
-				.Where(a => a != null)
+				.Where(udi => udi != null)
+				// do NOT filter out entires with blank tags. blank is the valid way to show the absence of tags
+				.Select(t => (t.Book.AudibleProductId, t.Tags))
 				.ToList();
-			foreach (var t in tagSets)
-				FileManager.TagsPersistence.Save(t.Book.AudibleProductId, t.Tags);
+
+			FileManager.TagsPersistence.Save(tagsCollection);
 		}
 	}
 }

DataLayer/_HowTo- EF Core.txt

@@ -7,15 +7,22 @@ nuget
 Microsoft.EntityFrameworkCore.Tools (needed for using Package Manager Console)
 Microsoft.EntityFrameworkCore.Sqlite
 
-MIGRATIONS require standard, not core
-using standard instead of core. edit 3 things in csproj
-1of3: pluralize xml TargetFramework tag to TargetFrameworks
-2of2: TargetFrameworks from: netstandard2.1
-to: netcoreapp3.0;netstandard2.1
-3of3: add
-  <PropertyGroup>
-    <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
-  </PropertyGroup>
+MIGRATIONS
+  require core, not standard
+  this can be a problem b/c standard and framework can only reference standard, not core
+TO USE MIGRATIONS (core and/or standard)
+  add to csproj
+    <PropertyGroup>
+      <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
+    </PropertyGroup>
+TO USE MIGRATIONS AS *BOTH* CORE AND STANDARD
+  edit csproj
+    pluralize this xml tag
+      from: TargetFramework
+      to: TargetFrameworks
+    inside of TargetFrameworks
+      from: netstandard2.1
+      to: netcoreapp3.0;netstandard2.1
 
 run. error
 SQLite Error 1: 'no such table: Blogs'.

DataLayer/appsettings.json

@@ -3,7 +3,10 @@
     "LibationContext_sqlserver": "Server=(LocalDb)\\MSSQLLocalDB;Database=DataLayer.LibationContext;Integrated Security=true;",
     "LibationContext": "Data Source=LibationContext.db;Foreign Keys=False;",
 
-    "// on windows sqlite paths accept windows and/or unix slashes": "",
+    "// sqlite notes": "",
+    "// absolute path example": "Data Source=C:/foo/bar/sample.db",
+    "// relative path example": "Data Source=sample.db",
+    "// on windows: sqlite paths accept windows and/or unix slashes": "",
     "MyTestContext": "Data Source=%DESKTOP%/sample.db"
   }
 }

FileLiberator/UNTESTED/DecryptBook.cs

@@ -94,6 +94,7 @@ namespace FileLiberator
                 NarratorsDiscovered?.Invoke(this, converter.tags.narrator);
                 CoverImageFilepathDiscovered?.Invoke(this, converter.coverBytes);
 
+				// override default which was set in CreateAsync
                 converter.SetOutputFilename(proposedOutputFile);
                 converter.DecryptProgressUpdate += (s, progress) => UpdateProgress?.Invoke(this, progress);
 
@@ -117,46 +118,58 @@ namespace FileLiberator
         }
 
         private static void moveFilesToBooksDir(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();
+		{
+			// create final directory. move each file into it. MOVE AUDIO FILE LAST
+			// new dir: safetitle_limit50char + " [" + productId + "]"
 
-            // create final directory. move each file into it. MOVE AUDIO FILE LAST
-            // new dir: safetitle_limit50char + " [" + productId + "]"
+			var destinationDir = getDestDir(product);
+			Directory.CreateDirectory(destinationDir);
 
-            // to prevent the paths from getting too long, we don't need after the 1st ":" for the folder
-            var underscoreIndex = product.Title.IndexOf(':');
-            var titleDir = (underscoreIndex < 4) ? product.Title : product.Title.Substring(0, underscoreIndex);
-            var finalDir = FileUtility.GetValidFilename(AudibleFileStorage.BooksDirectory, titleDir, null, product.AudibleProductId);
-            Directory.CreateDirectory(finalDir);
+			var sortedFiles = getProductFilesSorted(product, outputAudioFilename);
 
-            // move audio files to the end of the collection so these files are moved last
-            var musicFiles = files.Where(f => AudibleFileStorage.Audio.IsFileTypeMatch(f));
-            files = files
-                .Except(musicFiles)
-                .Concat(musicFiles)
-                .ToList();
+			var musicFileExt = Path.GetExtension(outputAudioFilename).Trim('.');
 
-            var musicFileExt = musicFiles
-                .Select(f => f.Extension)
-                .Distinct()
-                .Single()
-                .Trim('.');
+			foreach (var f in sortedFiles)
+			{
+				var dest = AudibleFileStorage.Audio.IsFileTypeMatch(f)
+					// audio filename: safetitle_limit50char + " [" + productId + "]." + audio_ext
+					? FileUtility.GetValidFilename(destinationDir, product.Title, musicFileExt, product.AudibleProductId)
+					// non-audio filename: safetitle_limit50char + " [" + productId + "][" + audio_ext +"]." + non_audio_ext
+					: FileUtility.GetValidFilename(destinationDir, product.Title, f.Extension, product.AudibleProductId, musicFileExt);
 
-            foreach (var f in files)
-            {
-                var dest = AudibleFileStorage.Audio.IsFileTypeMatch(f)
-                    // audio filename: safetitle_limit50char + " [" + productId + "]." + audio_ext
-                    ? FileUtility.GetValidFilename(finalDir, product.Title, musicFileExt, product.AudibleProductId)
-                    // non-audio filename: safetitle_limit50char + " [" + productId + "][" + audio_ext +"]." + non_audio_ext
-                    : FileUtility.GetValidFilename(finalDir, product.Title, f.Extension, product.AudibleProductId, musicFileExt);
+				File.Move(f.FullName, dest);
+			}
+		}
 
-                File.Move(f.FullName, dest);
-            }
-        }
-    }
+		private static string getDestDir(Book product)
+		{
+			// to prevent the paths from getting too long, we don't need after the 1st ":" for the folder
+			var underscoreIndex = product.Title.IndexOf(':');
+			var titleDir
+				= underscoreIndex < 4
+				? product.Title
+				: product.Title.Substring(0, underscoreIndex);
+			var finalDir = FileUtility.GetValidFilename(AudibleFileStorage.BooksDirectory, titleDir, null, product.AudibleProductId);
+			return finalDir;
+		}
+
+		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;
+		}
+	}
 }

FileLiberator/UNTESTED/DownloadBook.cs

@@ -44,6 +44,14 @@ namespace FileLiberator
 				tempAaxFilename,
 				(p) => api.DownloadAaxWorkaroundAsync(libraryBook.Book.AudibleProductId, tempAaxFilename, p));
 
+			// if bad file download, a 0-33 byte file will be created
+			System.Threading.Thread.Sleep(100);
+			if (new FileInfo(actualFilePath).Length < 100)
+			{
+				File.Delete(actualFilePath);
+				throw new Exception("Error downloading file");
+			}
+
 			return actualFilePath;
 		}
 

FileManager/UNTESTED/FilePathCache.cs

@@ -2,11 +2,12 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using Dinah.Core.Collections.Immutable;
 using Newtonsoft.Json;
 
 namespace FileManager
 {
-    public static class FilePathCache
+	public static class FilePathCache
     {
         internal class CacheEntry
         {
@@ -15,22 +16,25 @@ namespace FileManager
             public string Path { get; set; }
         }
 
-        static List<CacheEntry> inMemoryCache { get; } = new List<CacheEntry>();
+        static Cache<CacheEntry> cache { get; } = new Cache<CacheEntry>();
 
         public static string JsonFile => Path.Combine(Configuration.Instance.LibationFiles, "FilePaths.json");
 
         static FilePathCache()
         {
-            // load json into memory. if file doesn't exist, nothing to do. save() will create if needed
-            if (FileUtility.FileExists(JsonFile))
-                inMemoryCache = JsonConvert.DeserializeObject<List<CacheEntry>>(File.ReadAllText(JsonFile));
+			// load json into memory. if file doesn't exist, nothing to do. save() will create if needed
+			if (FileUtility.FileExists(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 = inMemoryCache.SingleOrDefault(i => i.Id == id && i.FileType == type);
+            var entry = cache.SingleOrDefault(i => i.Id == id && i.FileType == type);
 
             if (entry == null)
                 return null;
@@ -44,51 +48,47 @@ namespace FileManager
             return entry.Path;
         }
 
-        private static object locker { get; } = new object();
-
         private static void remove(CacheEntry entry)
-        {
-            lock (locker)
-            {
-                inMemoryCache.Remove(entry);
-                save();
-            }
-        }
+		{
+			cache.Remove(entry);
+			save();
+		}
 
         public static void Upsert(string id, FileType type, string path)
         {
             if (!FileUtility.FileExists(path))
                 throw new FileNotFoundException("Cannot add path to cache. File not found");
 
-            lock (locker)
-            {
-                var entry = inMemoryCache.SingleOrDefault(i => i.Id == id && i.FileType == type);
-                if (entry != null)
-                    entry.Path = path;
-                else
-                {
-                    entry = new CacheEntry { Id = id, FileType = type, Path = path };
-                    inMemoryCache.Add(entry);
-                }
-                save();
-            }
-        }
+			var entry = cache.SingleOrDefault(i => i.Id == id && i.FileType == type);
 
-        // ONLY call this within lock()
-        private static void save()
-        {
-            // create json if not exists
-            void resave() => File.WriteAllText(JsonFile, JsonConvert.SerializeObject(inMemoryCache, Formatting.Indented));
-            try { resave(); }
-            catch (IOException)
-            {
-                try { resave(); }
-                catch (IOException ex)
+			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)
 				{
-					Serilog.Log.Logger.Error(ex, "Error saving FilePaths.json");
-                    throw;
-                }
-            }
+					try { resave(); }
+					catch (IOException ex)
+					{
+						Serilog.Log.Logger.Error(ex, "Error saving FilePaths.json");
+						throw;
+					}
+				}
+			}
         }
     }
 }

FileManager/UNTESTED/TagsPersistence.cs

@@ -27,11 +27,13 @@ namespace FileManager
 			= Policy.Handle<Exception>()
 			.WaitAndRetry(new[] { TimeSpan.FromMilliseconds(100) });
 
-        public static void Save(string productId, string tags)
+		public static void Save(IEnumerable<(string productId, string tags)> tagsCollection)
 		{
 			ensureCache();
 
-			cache[productId] = tags;
+			// on initial reload, there's a huge benefit to adding to cache individually then updating the file only once
+			foreach ((string productId, string tags) in tagsCollection)
+				cache[productId] = tags;
 
 			lock (locker)
 				policy.Execute(() => File.WriteAllText(TagsFile, JsonConvert.SerializeObject(cache, Formatting.Indented)));

LibationWinForm/UNTESTED/BookLiberation/DecryptForm.cs

@@ -8,7 +8,13 @@ namespace LibationWinForm.BookLiberation
 {
     public partial class DecryptForm : Form
     {
-        public DecryptForm()
+		class SerilogTextWriter : System.IO.TextWriter
+		{
+			public override System.Text.Encoding Encoding => System.Text.Encoding.ASCII;
+			public override void WriteLine(string value) => Serilog.Log.Logger.Debug(value);
+		}
+
+		public DecryptForm()
         {
             InitializeComponent();
         }
@@ -18,7 +24,7 @@ namespace LibationWinForm.BookLiberation
         {
             // redirect Console.WriteLine to console, textbox
             var controlWriter = new RichTextBoxTextWriter(this.rtbLog);
-            var multiLogger = new MultiTextWriter(origOut, controlWriter);
+            var multiLogger = new MultiTextWriter(origOut, controlWriter, new SerilogTextWriter());
             Console.SetOut(multiLogger);
         }
 
@@ -57,19 +63,6 @@ namespace LibationWinForm.BookLiberation
         public void SetCoverImage(byte[] coverBytes)
             => pictureBox1.UIThread(() => pictureBox1.Image = ImageReader.ToImage(coverBytes));
 
-		public void AppendError(Exception ex)
-		{
-			Serilog.Log.Logger.Error(ex, "Decrypt form: error");
-			appendText("ERROR: " + ex.Message);
-		}
-		public void AppendText(string text)
-		{
-			Serilog.Log.Logger.Debug($"Decrypt form: {text}");
-			appendText(text);
-		}
-		private void appendText(string text) => Console.WriteLine($"{DateTime.Now} {text}");
-
-
 		public void UpdateProgress(int percentage) => progressBar1.UIThread(() => progressBar1.Value = percentage);
     }
 }

LibationWinForm/UNTESTED/Form1.cs

@@ -111,7 +111,7 @@ namespace LibationWinForm
 
 			setBookBackupCounts(books);
 			setPdfBackupCounts(books);
-        }
+		}
         enum AudioFileState { full, aax, none }
         private void setBookBackupCounts(IEnumerable<Book> books)
         {

REFERENCE.txt

@@ -1,6 +1,8 @@
 -- begin VERSIONING ---------------------------------------------------------------------------------------------------------------------
 https://github.com/rmcrackan/Libation/releases
 
+v3.1-beta.8 : Bugfix: decrypt file conflict
+v3.1-beta.7 : Bugfix: decrypt book with no author
 v3.1-beta.6 : Improved logging
 v3.1-beta.5 : Improved importing
 v3.1-beta.4 : Added beta-specific logging