Add initial EditorBeatmap structure

osu.Game/Rulesets/Edit/HitObjectComposer.cs

@@ -18,6 +18,7 @@ using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Drawables;
 using osu.Game.Rulesets.UI;
+using osu.Game.Screens.Edit;
 using osu.Game.Screens.Edit.Components.RadioButtons;
 using osu.Game.Screens.Edit.Compose.Components;
 
@@ -185,6 +186,19 @@ namespace osu.Game.Rulesets.Edit
         {
         }
 
+        protected override IReadOnlyDependencyContainer CreateChildDependencies(IReadOnlyDependencyContainer parent)
+        {
+            var workingBeatmap = parent.Get<IBindable<WorkingBeatmap>>();
+            var playableBeatmap = (Beatmap<TObject>)workingBeatmap.Value.GetPlayableBeatmap(Ruleset.RulesetInfo, Array.Empty<Mod>());
+            var editorBeatmap = new EditorBeatmap<TObject>(playableBeatmap);
+
+            var dependencies = new DependencyContainer(base.CreateChildDependencies(parent));
+            dependencies.CacheAs(editorBeatmap);
+            dependencies.CacheAs<IEditorBeatmap>(editorBeatmap);
+
+            return dependencies;
+        }
+
         internal override DrawableEditRuleset CreateDrawableRuleset()
             => new DrawableEditRuleset<TObject>(CreateDrawableRuleset(Ruleset, Beatmap.Value, Array.Empty<Mod>()));
 

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);
+    }
+}

osu.Game/Screens/Edit/IEditorBeatmap.cs

@@ -0,0 +1,17 @@
+// 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 osu.Game.Rulesets.Objects;
+
+namespace osu.Game.Screens.Edit
+{
+    public interface IEditorBeatmap
+    {
+        event Action<HitObject> HitObjectAdded;
+        event Action<HitObject> HitObjectRemoved;
+
+        void Add(HitObject hitObject);
+        void Remove(HitObject hitObject);
+    }
+}