Refactor HitObject selection in Composer

osu.Game.Rulesets.Mania/Edit/ManiaHitObjectComposer.cs

@@ -3,16 +3,15 @@
 
 #nullable disable
 
-using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text.RegularExpressions;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Edit;
 using osu.Game.Rulesets.Edit.Tools;
 using osu.Game.Rulesets.Mania.Objects;
 using osu.Game.Rulesets.Mania.UI;
 using osu.Game.Rulesets.Mods;
-using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.UI;
 using osu.Game.Rulesets.UI.Scrolling;
 using osu.Game.Screens.Edit.Compose.Components;
@@ -50,22 +49,44 @@ namespace osu.Game.Rulesets.Mania.Edit
             new HoldNoteCompositionTool()
         };
 
+        private static readonly Regex selection_regex = new Regex(@"^\d+\|\d+(,\d+\|\d+)*$");
+
         public override string ConvertSelectionToString()
-            => string.Join(ObjectSeparator, EditorBeatmap.SelectedHitObjects.Cast<ManiaHitObject>().OrderBy(h => h.StartTime).Select(h => $"{h.StartTime}|{h.Column}"));
+            => string.Join(',', EditorBeatmap.SelectedHitObjects.Cast<ManiaHitObject>().OrderBy(h => h.StartTime).Select(h => $"{h.StartTime}|{h.Column}"));
 
-        public override bool HandleHitObjectSelection(HitObject hitObject, string objectInfo)
+        public override void SelectHitObjects(double timestamp, string objectDescription)
         {
-            if (hitObject is not ManiaHitObject maniaHitObject)
-                return false;
+            if (!selection_regex.IsMatch(objectDescription))
+                return;
 
-            double[] split = objectInfo.Split('|').Select(double.Parse).ToArray();
+            List<ManiaHitObject> remainingHitObjects = EditorBeatmap.HitObjects.Cast<ManiaHitObject>().Where(h => h.StartTime >= timestamp).ToList();
+            string[] split = objectDescription.Split(',').ToArray();
+
+            for (int i = 0; i < split.Length; i++)
+            {
+                ManiaHitObject current = remainingHitObjects.FirstOrDefault(h => shouldBeSelected(h, split[i]));
+
+                if (current == null)
+                    continue;
+
+                EditorBeatmap.SelectedHitObjects.Add(current);
+
+                if (i < split.Length - 1)
+                    remainingHitObjects = remainingHitObjects.Where(h => h != current && h.StartTime >= current.StartTime).ToList();
+            }
+        }
+
+        private bool shouldBeSelected(ManiaHitObject hitObject, string objectInfo)
+        {
+            string[] split = objectInfo.Split('|').ToArray();
             if (split.Length != 2)
                 return false;
 
-            double timeValue = split[0];
-            double columnValue = split[1];
-            return Math.Abs(maniaHitObject.StartTime - timeValue) < 0.5
-                   && Math.Abs(maniaHitObject.Column - columnValue) < 0.5;
+            if (!double.TryParse(split[0], out double time) || !int.TryParse(split[1], out int column))
+                return false;
+
+            return hitObject.StartTime == time
+                   && hitObject.Column == column;
         }
     }
 }

osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs

@@ -6,6 +6,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text.RegularExpressions;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Caching;
@@ -103,18 +104,39 @@ namespace osu.Game.Rulesets.Osu.Edit
         protected override ComposeBlueprintContainer CreateBlueprintContainer()
             => new OsuBlueprintContainer(this);
 
+        private static readonly Regex selection_regex = new Regex(@"^\d+(,\d+)*$");
+
         public override string ConvertSelectionToString()
-            => string.Join(ObjectSeparator, selectedHitObjects.Cast<OsuHitObject>().OrderBy(h => h.StartTime).Select(h => (h.IndexInCurrentCombo + 1).ToString()));
+            => string.Join(',', selectedHitObjects.Cast<OsuHitObject>().OrderBy(h => h.StartTime).Select(h => (h.IndexInCurrentCombo + 1).ToString()));
 
-        public override bool HandleHitObjectSelection(HitObject hitObject, string objectInfo)
+        public override void SelectHitObjects(double timestamp, string objectDescription)
         {
-            if (hitObject is not OsuHitObject osuHitObject)
+            if (!selection_regex.IsMatch(objectDescription))
+                return;
+
+            List<OsuHitObject> remainingHitObjects = EditorBeatmap.HitObjects.Cast<OsuHitObject>().Where(h => h.StartTime >= timestamp).ToList();
+            string[] split = objectDescription.Split(',').ToArray();
+
+            for (int i = 0; i < split.Length; i++)
+            {
+                OsuHitObject current = remainingHitObjects.FirstOrDefault(h => shouldBeSelected(h, split[i]));
+
+                if (current == null)
+                    continue;
+
+                EditorBeatmap.SelectedHitObjects.Add(current);
+
+                if (i < split.Length - 1)
+                    remainingHitObjects = remainingHitObjects.Where(h => h != current && h.StartTime >= current.StartTime).ToList();
+            }
+        }
+
+        private bool shouldBeSelected(OsuHitObject hitObject, string objectInfo)
+        {
+            if (!int.TryParse(objectInfo, out int combo) || combo < 1)
                 return false;
 
-            if (!int.TryParse(objectInfo, out int comboValue) || comboValue < 1)
-                return false;
-
-            return osuHitObject.IndexInCurrentCombo + 1 == comboValue;
+            return hitObject.IndexInCurrentCombo + 1 == combo;
         }
 
         private DistanceSnapGrid distanceSnapGrid;

osu.Game/Rulesets/Edit/EditorTimestampParser.cs

@@ -2,11 +2,9 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
-using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
 using System.Text.RegularExpressions;
-using osu.Game.Rulesets.Objects;
 
 namespace osu.Game.Rulesets.Edit
 {
@@ -31,43 +29,7 @@ namespace osu.Game.Rulesets.Edit
 
             Debug.Assert(times.Length == 3);
 
-            return (times[0] * 60 + times[1]) * 1_000 + times[2];
-        }
-
-        public static List<HitObject> GetSelectedHitObjects(HitObjectComposer composer, IReadOnlyList<HitObject> editorHitObjects, string objectsGroup, double position)
-        {
-            List<HitObject> hitObjects = editorHitObjects.Where(x => x.StartTime >= position).ToList();
-            List<HitObject> selectedObjects = new List<HitObject>();
-
-            string[] objectsToSelect = objectsGroup.Split(composer.ObjectSeparator).ToArray();
-
-            foreach (string objectInfo in objectsToSelect)
-            {
-                HitObject? current = hitObjects.FirstOrDefault(x => composer.HandleHitObjectSelection(x, objectInfo));
-
-                if (current == null)
-                    continue;
-
-                selectedObjects.Add(current);
-                hitObjects = hitObjects.Where(x => x != current && x.StartTime >= current.StartTime).ToList();
-            }
-
-            // Stable behavior
-            // - always selects the next closest object when `objectsGroup` only has one (combo) item
-            if (objectsToSelect.Length != 1 || objectsGroup.Contains('|'))
-                return selectedObjects;
-
-            HitObject? nextClosest = editorHitObjects.FirstOrDefault(x => x.StartTime >= position);
-            if (nextClosest == null)
-                return selectedObjects;
-
-            if (nextClosest.StartTime <= (selectedObjects.FirstOrDefault()?.StartTime ?? position))
-            {
-                selectedObjects.Clear();
-                selectedObjects.Add(nextClosest);
-            }
-
-            return selectedObjects;
+            return (times[0] * 60 + times[1]) * 1000 + times[2];
         }
     }
 }

osu.Game/Rulesets/Edit/HitObjectComposer.cs

@@ -529,17 +529,11 @@ namespace osu.Game.Rulesets.Edit
         public virtual string ConvertSelectionToString() => string.Empty;
 
         /// <summary>
-        /// The custom logic that decides whether a HitObject should be selected when clicking an editor timestamp link
+        /// Each ruleset has it's own selection method
         /// </summary>
-        /// <param name="hitObject">The hitObject being checked</param>
-        /// <param name="objectInfo">A single hitObject's information created with <see cref="ConvertSelectionToString"/></param>
-        /// <returns>Whether a HitObject should be selected or not</returns>
-        public virtual bool HandleHitObjectSelection(HitObject hitObject, string objectInfo) => false;
-
-        /// <summary>
-        /// A character that separates the selection in <see cref="ConvertSelectionToString"/>
-        /// </summary>
-        public virtual char ObjectSeparator => ',';
+        /// <param name="timestamp">The given timestamp</param>
+        /// <param name="objectDescription">The selected object information between the brackets</param>
+        public virtual void SelectHitObjects(double timestamp, string objectDescription) { }
 
         #region IPositionSnapProvider
 

osu.Game/Screens/Edit/Editor.cs

@@ -1194,15 +1194,8 @@ namespace osu.Game.Screens.Edit
             if (Mode.Value != EditorScreenMode.Compose)
                 Mode.Value = EditorScreenMode.Compose;
 
-            List<HitObject> selected = EditorTimestampParser.GetSelectedHitObjects(
-                currentScreen.Dependencies.Get<HitObjectComposer>(),
-                editorBeatmap.HitObjects.ToList(),
-                objectsGroup,
-                position
-            );
-
-            if (selected.Any())
-                editorBeatmap.SelectedHitObjects.AddRange(selected);
+            // Let the Ruleset handle selection
+            currentScreen.Dependencies.Get<HitObjectComposer>().SelectHitObjects(position, objectsGroup);
         }
 
         public double SnapTime(double time, double? referenceTime) => editorBeatmap.SnapTime(time, referenceTime);