Add initial EditorBeatmap structure

osu.Game/Screens/Edit/EditorBeatmap.cs

@@ -0,0 +1,79 @@
+// 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 System;
+using System.Collections.Generic;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Beatmaps.Timing;
+using osu.Game.Rulesets.Objects;
+
+namespace osu.Game.Screens.Edit
+{
+    public class EditorBeatmap<T> : IBeatmap<T>, IEditorBeatmap
+        where T : HitObject
+    {
+        public event Action<T> HitObjectRemoved;
+        public event Action<T> HitObjectAdded;
+
+        event Action<HitObject> IEditorBeatmap.HitObjectAdded
+        {
+            add => HitObjectAdded += value;
+            remove => HitObjectAdded -= value;
+        }
+
+        event Action<HitObject> IEditorBeatmap.HitObjectRemoved
+        {
+            add => HitObjectRemoved += value;
+            remove => HitObjectRemoved -= value;
+        }
+
+        private readonly Beatmap<T> beatmap;
+
+        public EditorBeatmap(Beatmap<T> beatmap)
+        {
+            this.beatmap = beatmap;
+        }
+
+        public BeatmapInfo BeatmapInfo
+        {
+            get => beatmap.BeatmapInfo;
+            set => beatmap.BeatmapInfo = value;
+        }
+
+        public BeatmapMetadata Metadata => beatmap.Metadata;
+
+        public ControlPointInfo ControlPointInfo => beatmap.ControlPointInfo;
+
+        public List<BreakPeriod> Breaks => beatmap.Breaks;
+
+        public double TotalBreakTime => beatmap.TotalBreakTime;
+
+        IReadOnlyList<T> IBeatmap<T>.HitObjects => beatmap.HitObjects;
+
+        IReadOnlyList<HitObject> IBeatmap.HitObjects => beatmap.HitObjects;
+
+        public IEnumerable<BeatmapStatistic> GetStatistics() => beatmap.GetStatistics();
+
+        public IBeatmap Clone() => (EditorBeatmap<T>)MemberwiseClone();
+
+        public void Add(T hitObject)
+        {
+            // Preserve existing sorting order in the beatmap
+            var insertionIndex = beatmap.HitObjects.FindLastIndex(h => h.StartTime <= hitObject.StartTime);
+            beatmap.HitObjects.Insert(insertionIndex + 1, hitObject);
+
+            HitObjectAdded?.Invoke(hitObject);
+        }
+
+        public void Remove(T hitObject)
+        {
+            if (beatmap.HitObjects.Remove(hitObject))
+                HitObjectRemoved?.Invoke(hitObject);
+        }
+
+        public void Add(HitObject hitObject) => Add((T)hitObject);
+
+        public void Remove(HitObject hitObject) => Remove((T)hitObject);
+    }
+}