Fixed: Cleanup First Character in Name when using 'NameFirstCharacter'

(cherry picked from commit b3c691859a0841cde9bb2655c01c240cc5279d74)

Closes #4179

src/NzbDrone.Core.Test/OrganizerTests/FileNameBuilderTests/ArtistNameFirstCharacterFixture.cs

@@ -37,6 +37,11 @@ namespace NzbDrone.Core.Test.OrganizerTests.FileNameBuilderTests
         [TestCase("The Mist", "M", "The Mist")]
         [TestCase("A", "A", "A")]
         [TestCase("30 Rock", "3", "30 Rock")]
+        [TestCase("The '80s Greatest", "8", "The '80s Greatest")]
+        [TestCase("좀비버스", "좀", "좀비버스")]
+        [TestCase("¡Mucha Lucha!", "M", "¡Mucha Lucha!")]
+        [TestCase(".hack", "H", "hack")]
+        [TestCase("Ütopya", "U", "Ütopya")]
         public void should_get_expected_folder_name_back(string title, string parent, string child)
         {
             _artist.Name = title;

src/NzbDrone.Core/Organizer/FileNameBuilder.cs

@@ -264,6 +264,23 @@ namespace NzbDrone.Core.Organizer
             return TitlePrefixRegex.Replace(title, "$2, $1$3");
         }
 
+        public static string TitleFirstCharacter(string title)
+        {
+            if (char.IsLetterOrDigit(title[0]))
+            {
+                return title.Substring(0, 1).ToUpper().RemoveAccent();
+            }
+
+            // Try the second character if the first was non alphanumeric
+            if (char.IsLetterOrDigit(title[1]))
+            {
+                return title.Substring(1, 1).ToUpper().RemoveAccent();
+            }
+
+            // Default to "_" if no alphanumeric character can be found in the first 2 positions
+            return "_";
+        }
+
         public static string CleanFileName(string name)
         {
             return CleanFileName(name, NamingConfig.Default);
@@ -282,7 +299,7 @@ namespace NzbDrone.Core.Organizer
             tokenHandlers["{Artist CleanName}"] = m => CleanTitle(artist.Name);
             tokenHandlers["{Artist NameThe}"] = m => TitleThe(artist.Name);
             tokenHandlers["{Artist Genre}"] = m => artist.Metadata.Value.Genres?.FirstOrDefault() ?? string.Empty;
-            tokenHandlers["{Artist NameFirstCharacter}"] = m => TitleThe(artist.Name).Substring(0, 1).FirstCharToUpper();
+            tokenHandlers["{Artist NameFirstCharacter}"] = m => TitleFirstCharacter(TitleThe(artist.Name));
             tokenHandlers["{Artist MbId}"] = m => artist.ForeignArtistId ?? string.Empty;
 
             if (artist.Metadata.Value.Disambiguation != null)