From 51e5dd7d0e58fb681db6da9e34e9d435e1026a58 Mon Sep 17 00:00:00 2001
From: Salman Ahmed <frenzibyte@gmail.com>
Date: Fri, 18 Mar 2022 02:08:11 +0300
Subject: [PATCH] Introduce `IsPlayable(...)` and obsolete `UserPlayable`

---
 .../BeatmapSet/LeaderboardModSelector.cs      |  2 +-
 osu.Game/Rulesets/Mods/IMod.cs                | 26 ++++++++++---------
 osu.Game/Rulesets/Mods/Mod.cs                 | 11 +++-----
 osu.Game/Rulesets/Mods/ModUsage.cs            | 26 +++++++++++++++++++
 4 files changed, 45 insertions(+), 20 deletions(-)
 create mode 100644 osu.Game/Rulesets/Mods/ModUsage.cs

diff --git a/osu.Game/Overlays/BeatmapSet/LeaderboardModSelector.cs b/osu.Game/Overlays/BeatmapSet/LeaderboardModSelector.cs
index 25aed4c980..97b89c6f74 100644
--- a/osu.Game/Overlays/BeatmapSet/LeaderboardModSelector.cs
+++ b/osu.Game/Overlays/BeatmapSet/LeaderboardModSelector.cs
@@ -63,7 +63,7 @@ namespace osu.Game.Overlays.BeatmapSet
                 return;
 
             modsContainer.Add(new ModButton(new ModNoMod()));
-            modsContainer.AddRange(rulesetInstance.AllMods.Where(m => m.UserPlayable).Select(m => new ModButton(m)));
+            modsContainer.AddRange(rulesetInstance.AllMods.Where(m => m.IsPlayable(ModUsage.Solo)).Select(m => new ModButton(m)));
 
             modsContainer.ForEach(button =>
             {
diff --git a/osu.Game/Rulesets/Mods/IMod.cs b/osu.Game/Rulesets/Mods/IMod.cs
index 5f4fecb649..bdfb273b13 100644
--- a/osu.Game/Rulesets/Mods/IMod.cs
+++ b/osu.Game/Rulesets/Mods/IMod.cs
@@ -33,24 +33,26 @@ namespace osu.Game.Rulesets.Mods
         /// </summary>
         IconUsage? Icon { get; }
 
+        /// <summary>
+        /// Whether this mod is playable for the given usage.
+        /// </summary>
+        /// <remarks>
+        /// <list type="bullet">
+        /// <item>Should be always <c>false</c> for cases where the user is not interacting with the game.</item>
+        /// <item>Should be <c>false</c> in <see cref="ModUsage.MultiplayerRequired"/> for mods that make gameplay duration dependent on user input (e.g. <see cref="ModAdaptiveSpeed"/>).</item>
+        /// <item>Should be <c>false</c> in <see cref="ModUsage.MultiplayerFree"/> for mods that affect the gameplay duration (e.g. <see cref="ModRateAdjust"/> and <see cref="ModTimeRamp"/>).</item>
+        /// </list>
+        /// </remarks>
+        /// <param name="usage">The mod usage.</param>
+        bool IsPlayable(ModUsage usage);
+
         /// <summary>
         /// Whether this mod is playable by an end user.
         /// Should be <c>false</c> for cases where the user is not interacting with the game (so it can be excluded from multiplayer selection, for example).
         /// </summary>
+        [Obsolete("Override IsPlayable instead.")] // Can be removed 20220918
         bool UserPlayable { get; }
 
-        /// <summary>
-        /// Whether this mod is playable in a multiplayer match.
-        /// Should be <c>false</c> for mods that make gameplay duration dependent on user input (e.g. <see cref="ModAdaptiveSpeed"/>).
-        /// </summary>
-        bool PlayableInMultiplayer { get; }
-
-        /// <summary>
-        /// Whether this mod is valid to be a "free mod" in a multiplayer match.
-        /// Should be <c>false</c> for mods that affect the gameplay duration (e.g. <see cref="ModRateAdjust"/> and <see cref="ModTimeRamp"/>).
-        /// </summary>
-        bool ValidFreeModInMultiplayer { get; }
-
         /// <summary>
         /// Create a fresh <see cref="Mod"/> instance based on this mod.
         /// </summary>
diff --git a/osu.Game/Rulesets/Mods/Mod.cs b/osu.Game/Rulesets/Mods/Mod.cs
index a6562b4f4c..00aef1a598 100644
--- a/osu.Game/Rulesets/Mods/Mod.cs
+++ b/osu.Game/Rulesets/Mods/Mod.cs
@@ -91,16 +91,13 @@ namespace osu.Game.Rulesets.Mods
         [JsonIgnore]
         public virtual bool HasImplementation => this is IApplicableMod;
 
+        public virtual bool IsPlayable(ModUsage usage) => true;
+
         [JsonIgnore]
+        [Obsolete("Override IsPlayable instead.")] // Can be removed 20220918
         public virtual bool UserPlayable => true;
 
-        [JsonIgnore]
-        public virtual bool PlayableInMultiplayer => UserPlayable;
-
-        [JsonIgnore]
-        public virtual bool ValidFreeModInMultiplayer => PlayableInMultiplayer;
-
-        [Obsolete("Going forward, the concept of \"ranked\" doesn't exist. The only exceptions are automation mods, which should now override and set UserPlayable to false.")] // Can be removed 20211009
+        [Obsolete("Going forward, the concept of \"ranked\" doesn't exist. The only exceptions are automation mods, which should now override IsPlayable to false.")] // Can be removed 20211009
         public virtual bool Ranked => false;
 
         /// <summary>
diff --git a/osu.Game/Rulesets/Mods/ModUsage.cs b/osu.Game/Rulesets/Mods/ModUsage.cs
new file mode 100644
index 0000000000..82ff6bc418
--- /dev/null
+++ b/osu.Game/Rulesets/Mods/ModUsage.cs
@@ -0,0 +1,26 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+namespace osu.Game.Rulesets.Mods
+{
+    /// <summary>
+    /// The usage of this mod to determine its playability.
+    /// </summary>
+    public enum ModUsage
+    {
+        /// <summary>
+        /// In a solo gameplay session.
+        /// </summary>
+        Solo,
+
+        /// <summary>
+        /// In a multiplayer match, as a required mod.
+        /// </summary>
+        MultiplayerRequired,
+
+        /// <summary>
+        /// In a multiplayer match, as a "free" mod.
+        /// </summary>
+        MultiplayerFree,
+    }
+}