Split retrieving of beatmap and storyboard decoder

Storyboard works again. Not satisfied with the solution though.

osu.Game.Tests/Beatmaps/IO/OszArchiveReaderTest.cs

@@ -50,7 +50,7 @@ namespace osu.Game.Tests.Beatmaps.IO
 
                 BeatmapMetadata meta;
                 using (var stream = new StreamReader(reader.GetStream("Soleily - Renatus (Deif) [Platter].osu")))
-                    meta = BeatmapDecoder.GetDecoder(stream).DecodeBeatmap(stream).Metadata;
+                    meta = Decoder.GetBeatmapDecoder(stream).DecodeBeatmap(stream).Metadata;
 
                 Assert.AreEqual(241526, meta.OnlineBeatmapSetID);
                 Assert.AreEqual("Soleily", meta.Artist);

osu.Game/Beatmaps/BeatmapManager.cs

@@ -495,7 +495,7 @@ namespace osu.Game.Beatmaps
             BeatmapMetadata metadata;
 
             using (var stream = new StreamReader(reader.GetStream(mapName)))
-                metadata = BeatmapDecoder.GetDecoder(stream).DecodeBeatmap(stream).Metadata;
+                metadata = Decoder.GetBeatmapDecoder(stream).DecodeBeatmap(stream).Metadata;
 
             // check if a set already exists with the same online id.
             beatmapSet = beatmaps.BeatmapSets.FirstOrDefault(b => b.OnlineBeatmapSetID == metadata.OnlineBeatmapSetID) ?? new BeatmapSetInfo
@@ -518,7 +518,7 @@ namespace osu.Game.Beatmaps
                     raw.CopyTo(ms);
                     ms.Position = 0;
 
-                    var decoder = BeatmapDecoder.GetDecoder(sr);
+                    var decoder = Decoder.GetBeatmapDecoder(sr);
                     Beatmap beatmap = decoder.DecodeBeatmap(sr);
 
                     beatmap.BeatmapInfo.Path = name;
@@ -571,7 +571,7 @@ namespace osu.Game.Beatmaps
                 {
                     using (var stream = new StreamReader(store.GetStream(getPathForFile(BeatmapInfo.Path))))
                     {
-                        BeatmapDecoder decoder = BeatmapDecoder.GetDecoder(stream);
+                        Decoder decoder = Decoder.GetBeatmapDecoder(stream);
                         return decoder.DecodeBeatmap(stream);
                     }
                 }
@@ -620,9 +620,9 @@ namespace osu.Game.Beatmaps
 
                 try
                 {
-                    BeatmapDecoder decoder;
+                    Decoder decoder;
                     using (var stream = new StreamReader(store.GetStream(getPathForFile(BeatmapInfo.Path))))
-                        decoder = BeatmapDecoder.GetDecoder(stream);
+                        decoder = Decoder.GetStoryboardDecoder(stream);
 
                     using (var stream = new StreamReader(store.GetStream(getPathForFile(BeatmapSetInfo.StoryboardFile))))
                         return decoder.DecodeStoryboard(stream);

osu.Game/Beatmaps/Formats/BeatmapDecoder.cs

@@ -1,67 +0,0 @@
-// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
-// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
-
-using System;
-using System.Collections.Generic;
-using System.IO;
-using osu.Game.Storyboards;
-
-namespace osu.Game.Beatmaps.Formats
-{
-    public abstract class BeatmapDecoder
-    {
-        private static readonly Dictionary<string, Type> decoders = new Dictionary<string, Type>();
-
-        static BeatmapDecoder()
-        {
-            LegacyDecoder.Register();
-        }
-
-        public static BeatmapDecoder GetDecoder(StreamReader stream)
-        {
-            if (stream == null)
-                throw new ArgumentNullException(nameof(stream));
-
-            string line;
-            do { line = stream.ReadLine()?.Trim(); }
-            while (line != null && line.Length == 0);
-
-            if (line == null || !decoders.ContainsKey(line))
-                throw new IOException(@"Unknown file format");
-            return (BeatmapDecoder)Activator.CreateInstance(decoders[line], line);
-        }
-
-        protected static void AddDecoder<T>(string magic) where T : BeatmapDecoder
-        {
-            decoders[magic] = typeof(T);
-        }
-
-        public virtual Beatmap DecodeBeatmap(StreamReader stream) => ParseBeatmap(stream);
-
-        protected virtual Beatmap ParseBeatmap(StreamReader stream)
-        {
-            var beatmap = new Beatmap
-            {
-                BeatmapInfo = new BeatmapInfo
-                {
-                    Metadata = new BeatmapMetadata(),
-                    BaseDifficulty = new BeatmapDifficulty(),
-                },
-            };
-
-            ParseBeatmap(stream, beatmap);
-            return beatmap;
-        }
-
-        protected abstract void ParseBeatmap(StreamReader stream, Beatmap beatmap);
-
-        public virtual Storyboard DecodeStoryboard(StreamReader stream)
-        {
-            var storyboard = new Storyboard();
-            ParseStoryboard(stream, storyboard);
-            return storyboard;
-        }
-
-        protected abstract void ParseStoryboard(StreamReader stream, Storyboard storyboard);
-    }
-}

osu.Game/Beatmaps/Formats/Decoder.cs

@@ -0,0 +1,120 @@
+// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using osu.Game.Storyboards;
+
+namespace osu.Game.Beatmaps.Formats
+{
+    public abstract class Decoder
+    {
+        private static readonly Dictionary<string, Type> beatmapDecoders = new Dictionary<string, Type>();
+        private static readonly Dictionary<string, Type> storyboardDecoders = new Dictionary<string, Type>();
+
+        static Decoder()
+        {
+            LegacyDecoder.Register();
+        }
+
+        /// <summary>
+        /// Retrieves a <see cref="Decoder"/> to parse <see cref="Beatmap"/>s.
+        /// </summary>
+        /// <param name="stream">A stream pointing to the <see cref="Beatmap"/> to retrieve the version from.</param>
+        public static Decoder GetBeatmapDecoder(StreamReader stream)
+        {
+            string line = readFirstLine(stream);
+
+            if (line == null || !beatmapDecoders.ContainsKey(line))
+                throw new IOException(@"Unknown file format");
+            return (Decoder)Activator.CreateInstance(beatmapDecoders[line], line);
+        }
+
+        /// <summary>
+        /// Retrieves a <see cref="Decoder"/> to parse <see cref="Storyboard"/>s.
+        /// </summary>
+        /// <param name="stream">A stream pointing to the <see cref="Beatmap"/> to retrieve the version from.</param>
+        public static Decoder GetStoryboardDecoder(StreamReader stream)
+        {
+            string line = readFirstLine(stream);
+
+            if (line == null || !storyboardDecoders.ContainsKey(line))
+                throw new IOException(@"Unknown file format");
+            return (Decoder)Activator.CreateInstance(storyboardDecoders[line], line);
+        }
+
+        private static string readFirstLine(StreamReader stream)
+        {
+            if (stream == null)
+                throw new ArgumentNullException(nameof(stream));
+
+            string line;
+            do
+            { line = stream.ReadLine()?.Trim(); }
+            while (line != null && line.Length == 0);
+
+            return line;
+        }
+
+        /// <summary>
+        /// Adds the <see cref="Decoder"/> to the list of <see cref="Beatmap"/> and <see cref="Storyboard"/> decoder.
+        /// </summary>
+        /// <typeparam name="A">Type to decode a <see cref="Beatmap"/> with.</typeparam>
+        /// /// <typeparam name="B">Type to decode a <see cref="Storyboard"/> with.</typeparam>
+        /// <param name="version">A string representation of the version.</param>
+        protected static void AddDecoder<A, B>(string version) where A : Decoder where B : Decoder
+        {
+            beatmapDecoders[version] = typeof(A);
+            storyboardDecoders[version] = typeof(B);
+        }
+
+        /// <summary>
+        /// Adds the <see cref="Decoder"/> to the list of <see cref="Beatmap"/> decoder.
+        /// </summary>
+        /// <typeparam name="T">Type to decode a <see cref="Beatmap"/> with.</typeparam>
+        /// <param name="version">A string representation of the version.</param>
+        protected static void AddBeatmapDecoder<T>(string version) where T : Decoder
+        {
+            beatmapDecoders[version] = typeof(T);
+        }
+
+        /// <summary>
+        /// Adds the <see cref="Decoder"/> to the list of <see cref="Storyboard"/> decoder.
+        /// </summary>
+        /// <typeparam name="T">Type to decode a <see cref="Storyboard"/> with.</typeparam>
+        /// <param name="version">A string representation of the version.</param>
+        protected static void AddStoryboardDecoder<T>(string version) where T : Decoder
+        {
+            storyboardDecoders[version] = typeof(T);
+        }
+
+        public virtual Beatmap DecodeBeatmap(StreamReader stream) => ParseBeatmap(stream);
+
+        protected virtual Beatmap ParseBeatmap(StreamReader stream)
+        {
+            var beatmap = new Beatmap
+            {
+                BeatmapInfo = new BeatmapInfo
+                {
+                    Metadata = new BeatmapMetadata(),
+                    BaseDifficulty = new BeatmapDifficulty(),
+                },
+            };
+
+            ParseBeatmap(stream, beatmap);
+            return beatmap;
+        }
+
+        protected abstract void ParseBeatmap(StreamReader stream, Beatmap beatmap);
+
+        public virtual Storyboard DecodeStoryboard(StreamReader stream)
+        {
+            var storyboard = new Storyboard();
+            ParseStoryboard(stream, storyboard);
+            return storyboard;
+        }
+
+        protected abstract void ParseStoryboard(StreamReader stream, Storyboard storyboard);
+    }
+}

osu.Game/Beatmaps/Formats/LegacyBeatmapDecoder.cs

@@ -20,6 +20,15 @@ namespace osu.Game.Beatmaps.Formats
         private LegacySampleBank defaultSampleBank;
         private int defaultSampleVolume = 100;
 
+        public LegacyBeatmapDecoder()
+        {
+        }
+
+        public LegacyBeatmapDecoder(string header)
+        {
+            BeatmapVersion = int.Parse(header.Substring(17));
+        }
+
         protected override void ProcessSection(Section section, string line)
         {
             switch (section)

osu.Game/Beatmaps/Formats/LegacyDecoder.cs

@@ -9,34 +9,25 @@ using osu.Game.Storyboards;
 
 namespace osu.Game.Beatmaps.Formats
 {
-    public class LegacyDecoder : BeatmapDecoder
+    public abstract class LegacyDecoder : Decoder
     {
         public static void Register()
         {
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v14");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v14");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v13");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v13");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v12");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v12");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v11");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v11");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v10");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v10");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v9");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v9");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v8");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v8");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v7");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v7");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v6");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v6");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v5");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v5");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v4");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v4");
-            AddDecoder<LegacyBeatmapDecoder>(@"osu file format v3");
+            AddDecoder<LegacyBeatmapDecoder, LegacyStoryboardDecoder>(@"osu file format v3");
             // TODO: differences between versions
         }
 
-        public LegacyDecoder()
-        {
-        }
-
-        public LegacyDecoder(string header)
-        {
-            BeatmapVersion = int.Parse(header.Substring(17));
-        }
-
         protected Beatmap Beatmap;
         protected Storyboard Storyboard;
 
@@ -105,10 +96,7 @@ namespace osu.Game.Beatmaps.Formats
             }
         }
 
-        protected virtual void ProcessSection(Section section, string line)
+        protected abstract void ProcessSection(Section section, string line);
-        {
-
-        }
 
         /// <summary>
         /// Decodes any beatmap variables present in a line into their real values.

osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs

@@ -4,9 +4,6 @@
 using System;
 using System.Globalization;
 using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 using OpenTK;
 using OpenTK.Graphics;
 using osu.Framework.Graphics;

osu.Game/Tests/Visual/TestCasePlayer.cs

@@ -63,7 +63,7 @@ namespace osu.Game.Tests.Visual
 
             using (var stream = new MemoryStream(Encoding.UTF8.GetBytes(test_beatmap_data)))
             using (var reader = new StreamReader(stream))
-                beatmap = BeatmapDecoder.GetDecoder(reader).DecodeBeatmap(reader);
+                beatmap = Game.Beatmaps.Formats.Decoder.GetBeatmapDecoder(reader).DecodeBeatmap(reader);
 
             return beatmap;
         }

osu.Game/osu.Game.csproj

@@ -313,7 +313,7 @@
     <Compile Include="Beatmaps\Drawables\DifficultyIcon.cs" />
     <Compile Include="Beatmaps\Drawables\Panel.cs" />
     <Compile Include="Beatmaps\DummyWorkingBeatmap.cs" />
-    <Compile Include="Beatmaps\Formats\BeatmapDecoder.cs" />
+    <Compile Include="Beatmaps\Formats\Decoder.cs" />
     <Compile Include="Beatmaps\Formats\LegacyBeatmapDecoder.cs" />
     <Compile Include="Beatmaps\IO\ArchiveReader.cs" />
     <Compile Include="Beatmaps\IO\LegacyFilesystemReader.cs" />