cleanup libretro pathentry handling

- should close #4669

Presumably broke in 0681dd2 since that sets different game data before instantiating the libretro host. Relying on the game "name" when we actually want the core name was wrong to begin with imo, so I've simplified the logic to never rely on `GameInfo`.

Author: Morilli

src/BizHawk.Client.Common/CoreFileProvider.cs

@@ -27,12 +27,12 @@ public CoreFileProvider(
 		}
 
 		// Poop
-		public string GetRetroSaveRAMDirectory(IGameInfo game)
-			=> _pathEntries.RetroSaveRamAbsolutePath(game);
+		public string GetRetroSaveRAMDirectory(string corePath)
+			=> _pathEntries.RetroSaveRamAbsolutePath(Path.GetFileNameWithoutExtension(corePath));
 
 		// Poop
-		public string GetRetroSystemPath(IGameInfo game)
-			=> _pathEntries.RetroSystemAbsolutePath(game);
+		public string GetRetroSystemPath(string corePath)
+			=> _pathEntries.RetroSystemAbsolutePath(Path.GetFileNameWithoutExtension(corePath));
 
 		public string GetUserPath(string sysID, bool temp)
 		{

src/BizHawk.Client.Common/RomLoader.cs

@@ -849,7 +849,7 @@ public bool LoadRom(string path, CoreComm nextComm, string launchLibretroCore, s
 						game = new GameInfo { Name = Path.GetFileNameWithoutExtension(launchLibretroCore) };
 					}
 					game.System = VSystemID.Raw.Libretro;
-					var retro = new LibretroHost(nextComm, game, launchLibretroCore);
+					var retro = new LibretroHost(nextComm, launchLibretroCore);
 					nextEmulator = retro;
 
 					if (retro.Description.SupportsNoGame && string.IsNullOrEmpty(path))

src/BizHawk.Client.Common/config/PathEntryCollectionExtensions.cs

@@ -245,32 +245,19 @@ public static string SaveRamAbsolutePath(this PathEntryCollection collection, IG
 		}
 
 		// Shenanigans
-		public static string RetroSaveRamAbsolutePath(this PathEntryCollection collection, IGameInfo game)
+		public static string RetroSaveRamAbsolutePath(this PathEntryCollection collection, string coreName)
 		{
-			var name = game.FilesystemSafeName();
-			name = Path.GetDirectoryName(name);
-			if (name is null) name = string.Empty;
-			else if (name.Length is 0) name = game.FilesystemSafeName();
-			var pathEntry = collection[game.System, "Save RAM"]
-				?? collection[game.System, "Base"];
+			var pathEntry = collection[VSystemID.Raw.Libretro, "Save RAM"];
 
-			return Path.Combine(collection.AbsolutePathFor(pathEntry.Path, game.System), name);
+			return Path.Combine(collection.AbsolutePathFor(pathEntry.Path, VSystemID.Raw.Libretro), coreName);
 		}
 
 		// Shenanigans
-		public static string RetroSystemAbsolutePath(this PathEntryCollection collection, IGameInfo game)
+		public static string RetroSystemAbsolutePath(this PathEntryCollection collection, string coreName)
 		{
-			var name = game.FilesystemSafeName();
-			name = Path.GetDirectoryName(name);
-			if (string.IsNullOrEmpty(name))
-			{
-				name = game.FilesystemSafeName();
-			}
-
-			var pathEntry = collection[game.System, "System"]
-				?? collection[game.System, "Base"];
+			var pathEntry = collection[VSystemID.Raw.Libretro, "System"];
 
-			return Path.Combine(collection.AbsolutePathFor(pathEntry.Path, game.System), name);
+			return Path.Combine(collection.AbsolutePathFor(pathEntry.Path, VSystemID.Raw.Libretro), coreName);
 		}
 
 		public static string AutoSaveRamAbsolutePath(this PathEntryCollection collection, IGameInfo game, IMovie movie)

src/BizHawk.Client.EmuHawk/MainForm.Events.cs

@@ -220,7 +220,7 @@ private void OpenRomMenuItem_Click(object sender, EventArgs e)
 
 		private void OpenAdvancedMenuItem_Click(object sender, EventArgs e)
 		{
-			using var oac = new OpenAdvancedChooser(this, Config, CreateCoreComm, Game, RunLibretroCoreChooser);
+			using var oac = new OpenAdvancedChooser(this, Config, CreateCoreComm, RunLibretroCoreChooser);
 			if (this.ShowDialogWithTempMute(oac) == DialogResult.Cancel) return;
 
 			if (oac.Result == AdvancedRomLoaderType.LibretroLaunchNoGame)

src/BizHawk.Client.EmuHawk/OpenAdvancedChooser.cs

@@ -29,8 +29,6 @@ public partial class OpenAdvancedChooser : Form, IDialogParent
 
 		private RetroDescription _currentDescription;
 
-		private readonly IGameInfo _game;
-
 		private readonly Func<bool> _libretroCoreChooserCallback;
 
 		public IDialogController DialogController { get; }
@@ -39,11 +37,10 @@ public partial class OpenAdvancedChooser : Form, IDialogParent
 
 		public FilesystemFilterSet SuggestedExtensionFilter = null;
 
-		public OpenAdvancedChooser(IDialogController dialogController, Config config, Func<CoreComm> createCoreComm, IGameInfo game, Func<bool> libretroCoreChooserCallback)
+		public OpenAdvancedChooser(IDialogController dialogController, Config config, Func<CoreComm> createCoreComm, Func<bool> libretroCoreChooserCallback)
 		{
 			_config = config;
 			_createCoreComm = createCoreComm;
-			_game = game;
 			_libretroCoreChooserCallback = libretroCoreChooserCallback;
 			DialogController = dialogController;
 
@@ -82,7 +79,7 @@ private void RefreshLibretroCore(bool bootstrap)
 			try
 			{
 				var coreComm = _createCoreComm();
-				using var retro = new LibretroHost(coreComm, _game, core, true);
+				using var retro = new LibretroHost(coreComm, core, true);
 				if (retro.Description.SupportsNoGame)
 					btnLibretroLaunchNoGame.Enabled = true;
 				if (!string.IsNullOrEmpty(retro.Description.ValidExtensions))

src/BizHawk.Emulation.Common/Interfaces/ICoreFileProvider.cs

@@ -8,12 +8,12 @@ public interface ICoreFileProvider
 		/// <summary>
 		/// produces a path that contains saveram... because libretro cores need it
 		/// </summary>
-		string GetRetroSaveRAMDirectory(IGameInfo game);
+		string GetRetroSaveRAMDirectory(string corePath);
 
 		/// <summary>
 		/// produces a path for use as a libretro system path (different for each core)
 		/// </summary>
-		string GetRetroSystemPath(IGameInfo game);
+		string GetRetroSystemPath(string corePath);
 
 		/// <summary>
 		/// produces a 'user' path for a given system id

src/BizHawk.Emulation.Cores/Libretro/Libretro.cs

@@ -73,12 +73,11 @@ public void Exit()
 			}
 		}
 
-		/// <remarks>does not keep a reference to <paramref name="game"/></remarks>
-		public LibretroHost(CoreComm comm, IGameInfo game, string corePath, bool analysis = false)
+		public LibretroHost(CoreComm comm, string corePath, bool analysis = false)
 			: this(
 				comm,
-				libretroSystemDir: comm.CoreFileProvider.GetRetroSystemPath(game),
-				libretroSaveRAMDir: comm.CoreFileProvider.GetRetroSaveRAMDirectory(game),
+				libretroSystemDir: comm.CoreFileProvider.GetRetroSystemPath(corePath),
+				libretroSaveRAMDir: comm.CoreFileProvider.GetRetroSaveRAMDirectory(corePath),
 				corePath: corePath,
 				analysis: analysis) {}