Implement basic support of SystemSaveData and Cleanup IFileSystemProxy (#767)

* Implement basic support of SystemSaveData and Cleanup IFileSystemProxy

- Implement `OpenSystemSaveData` as a `IFileSystem` in `SaveHelper`:
  On real device, system saves data are stored encrypted, and we can't create an empty system save data for now. That's why if a user put his own dump of system save in `RyuFs\nand\system\save\`, we extract content in associated folder and open it as a `IFileSystem`. If the system save data don't exist, a folder is created.

- Cleanup `IFileSystemProxy` by adding a Helper class.

- Implement `GetSavePath` in `VirtualFileSystem` and remove `GetGameSavePath` in `SaveHelper`.

* remove the forgotten I

* Fix align

1 files changed, 28 insertions, 29 deletions

diff --git a/Ryujinx.HLE/FileSystem/SaveHelper.cs b/Ryujinx.HLE/FileSystem/SaveHelper.cs
index 51400458..a1072498 100644
--- a/Ryujinx.HLE/FileSystem/SaveHelper.cs
+++ b/Ryujinx.HLE/FileSystem/SaveHelper.cs
@@ -1,45 +1,44 @@
-using Ryujinx.HLE.HOS;
+using LibHac.Fs;
+using Ryujinx.HLE.HOS;
 using System.IO;
 
-using static Ryujinx.HLE.FileSystem.VirtualFileSystem;
-
 namespace Ryujinx.HLE.FileSystem
 {
     static class SaveHelper
     {
-        public static string GetSavePath(SaveInfo saveMetaData, ServiceCtx context)
+        public static IFileSystem OpenSystemSaveData(ServiceCtx context, ulong saveId)
         {
-            string baseSavePath   = NandPath;
-            ulong  currentTitleId = saveMetaData.TitleId;
+            SaveInfo saveInfo = new SaveInfo(0, (long)saveId, SaveDataType.SystemSaveData, SaveSpaceId.NandSystem);
+            string   savePath = context.Device.FileSystem.GetSavePath(context, saveInfo, false);
 
-            switch (saveMetaData.SaveSpaceId)
+            if (File.Exists(savePath))
             {
-                case SaveSpaceId.NandUser:
-                    baseSavePath = UserNandPath;
-                    break;
-                case SaveSpaceId.NandSystem:
-                    baseSavePath = SystemNandPath;
-                    break;
-                case SaveSpaceId.SdCard:
-                    baseSavePath = Path.Combine(SdCardPath, "Nintendo");
-                    break;
-            }
+                string tempDirectoryPath = $"{savePath}_temp";
 
-            baseSavePath = Path.Combine(baseSavePath, "save");
+                Directory.CreateDirectory(tempDirectoryPath);
 
-            if (saveMetaData.TitleId == 0 && saveMetaData.SaveDataType == SaveDataType.SaveData)
-            {
-                currentTitleId = context.Process.TitleId;
-            }
+                IFileSystem outputFolder = new LocalFileSystem(tempDirectoryPath);
+
+                using (LocalStorage systemSaveData = new LocalStorage(savePath, FileAccess.Read, FileMode.Open))
+                {
+                    IFileSystem saveFs = new LibHac.Fs.Save.SaveDataFileSystem(context.Device.System.KeySet, systemSaveData, IntegrityCheckLevel.None, false);
 
-            string saveAccount = saveMetaData.UserId.IsNull ? "savecommon" : saveMetaData.UserId.ToString();
+                    saveFs.CopyFileSystem(outputFolder);
+                }
 
-            string savePath = Path.Combine(baseSavePath,
-                saveMetaData.SaveId.ToString("x16"),
-                saveAccount,
-                saveMetaData.SaveDataType == SaveDataType.SaveData ? currentTitleId.ToString("x16") : string.Empty);
+                File.Delete(savePath);
+
+                Directory.Move(tempDirectoryPath, savePath);
+            }
+            else
+            {
+                if (!Directory.Exists(savePath))
+                {
+                    Directory.CreateDirectory(savePath);
+                }
+            }
 
-            return savePath;
+            return new LocalFileSystem(savePath);
         }
     }
-}
+}
\ No newline at end of file