Add abstract spectator screen class

osu.Game/Screens/Spectate/GameplayState.cs

@@ -0,0 +1,37 @@
+// 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.
+
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets;
+using osu.Game.Scoring;
+
+namespace osu.Game.Screens.Spectate
+{
+    /// <summary>
+    /// The gameplay state of a spectated user. This class is immutable.
+    /// </summary>
+    public class GameplayState
+    {
+        /// <summary>
+        /// The score which the user is playing.
+        /// </summary>
+        public readonly Score Score;
+
+        /// <summary>
+        /// The ruleset which the user is playing.
+        /// </summary>
+        public readonly Ruleset Ruleset;
+
+        /// <summary>
+        /// The beatmap which the user is playing.
+        /// </summary>
+        public readonly WorkingBeatmap Beatmap;
+
+        public GameplayState(Score score, Ruleset ruleset, WorkingBeatmap beatmap)
+        {
+            Score = score;
+            Ruleset = ruleset;
+            Beatmap = beatmap;
+        }
+    }
+}