From 66ed77ac91f7a9ab4cd6297833fba3f52a044bf5 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Fri, 28 Oct 2022 18:04:28 +0900
Subject: [PATCH] Rename and add documentation to function

---
 osu.Game/Beatmaps/BeatmapManager.cs    |  2 +-
 osu.Game/Database/LegacyExporter.cs    |  2 +-
 osu.Game/Extensions/ModelExtensions.cs | 16 +++++++++-------
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/osu.Game/Beatmaps/BeatmapManager.cs b/osu.Game/Beatmaps/BeatmapManager.cs
index befc56d244..965cc43815 100644
--- a/osu.Game/Beatmaps/BeatmapManager.cs
+++ b/osu.Game/Beatmaps/BeatmapManager.cs
@@ -340,7 +340,7 @@ namespace osu.Game.Beatmaps
             static string createBeatmapFilenameFromMetadata(BeatmapInfo beatmapInfo)
             {
                 var metadata = beatmapInfo.Metadata;
-                return $"{metadata.Artist} - {metadata.Title} ({metadata.Author.Username}) [{beatmapInfo.DifficultyName}].osu".GetValidArchiveContentFilename();
+                return $"{metadata.Artist} - {metadata.Title} ({metadata.Author.Username}) [{beatmapInfo.DifficultyName}].osu".GetValidFilename();
             }
         }
 
diff --git a/osu.Game/Database/LegacyExporter.cs b/osu.Game/Database/LegacyExporter.cs
index d9fdc40abc..16d7441dde 100644
--- a/osu.Game/Database/LegacyExporter.cs
+++ b/osu.Game/Database/LegacyExporter.cs
@@ -37,7 +37,7 @@ namespace osu.Game.Database
         /// <param name="item">The item to export.</param>
         public void Export(TModel item)
         {
-            string filename = $"{item.GetDisplayString().GetValidArchiveContentFilename()}{FileExtension}";
+            string filename = $"{item.GetDisplayString().GetValidFilename()}{FileExtension}";
 
             using (var stream = exportStorage.CreateFileSafely(filename))
                 ExportModelTo(item, stream);
diff --git a/osu.Game/Extensions/ModelExtensions.cs b/osu.Game/Extensions/ModelExtensions.cs
index f8db5f4e88..efb3c4d633 100644
--- a/osu.Game/Extensions/ModelExtensions.cs
+++ b/osu.Game/Extensions/ModelExtensions.cs
@@ -15,6 +15,8 @@ namespace osu.Game.Extensions
 {
     public static class ModelExtensions
     {
+        private static readonly Regex invalid_filename_chars = new Regex(@"(?!$)[^A-Za-z0-9_()[\]. \-]", RegexOptions.Compiled);
+
         /// <summary>
         /// Get the relative path in osu! storage for this file.
         /// </summary>
@@ -137,14 +139,14 @@ namespace osu.Game.Extensions
             return instance.OnlineID.Equals(other.OnlineID);
         }
 
-        private static readonly Regex invalid_filename_chars = new Regex(@"(?!$)[^A-Za-z0-9_()[\]. \-]", RegexOptions.Compiled);
-
         /// <summary>
-        /// Get a valid filename for use inside a zip file. Avoids backslashes being incorrectly converted to directories.
+        /// Create a valid filename which should work across all platforms.
         /// </summary>
-        public static string GetValidArchiveContentFilename(this string filename)
-        {
-            return invalid_filename_chars.Replace(filename, "_");
-        }
+        /// <remarks>
+        /// This function replaces all characters not included in a very pessimistic list which should be compatible
+        /// across all operating systems. We are using this in place of <see cref="Path.GetInvalidFileNameChars"/> as
+        /// that function does not have per-platform considerations (and is only made to work on windows).
+        /// </remarks>
+        public static string GetValidFilename(this string filename) => invalid_filename_chars.Replace(filename, "_");
     }
 }