From 08e3fe1def87187fe297fbfbf29441ce5500618e Mon Sep 17 00:00:00 2001
From: smoogipoo <smoogipoo@smgi.me>
Date: Wed, 17 Oct 2018 14:37:39 +0900
Subject: [PATCH] Add PlacementStarted event, rename placement methods

---
 .../Edit/Masks/HitCirclePlacementMask.cs      |  3 ++-
 osu.Game/Rulesets/Edit/PlacementMask.cs       | 27 +++++++++++++++++--
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/osu.Game.Rulesets.Osu/Edit/Masks/HitCirclePlacementMask.cs b/osu.Game.Rulesets.Osu/Edit/Masks/HitCirclePlacementMask.cs
index 0b248e20fe..08e417cf1a 100644
--- a/osu.Game.Rulesets.Osu/Edit/Masks/HitCirclePlacementMask.cs
+++ b/osu.Game.Rulesets.Osu/Edit/Masks/HitCirclePlacementMask.cs
@@ -33,7 +33,8 @@ namespace osu.Game.Rulesets.Osu.Edit.Masks
         {
             HitObject.StartTime = EditorClock.CurrentTime;
             HitObject.Position = e.MousePosition;
-            Finish();
+
+            EndPlacement();
             return true;
         }
 
diff --git a/osu.Game/Rulesets/Edit/PlacementMask.cs b/osu.Game/Rulesets/Edit/PlacementMask.cs
index fd1b670274..109244c34f 100644
--- a/osu.Game/Rulesets/Edit/PlacementMask.cs
+++ b/osu.Game/Rulesets/Edit/PlacementMask.cs
@@ -15,6 +15,11 @@ namespace osu.Game.Rulesets.Edit
 {
     public class PlacementMask : CompositeDrawable, IRequireHighFrequencyMousePosition
     {
+        /// <summary>
+        /// Invoked when the placement of <see cref="HitObject"/> has started.
+        /// </summary>
+        public event Action<HitObject> PlacementStarted;
+
         /// <summary>
         /// Invoked when the placement of <see cref="HitObject"/> has finished.
         /// </summary>
@@ -40,10 +45,27 @@ namespace osu.Game.Rulesets.Edit
             HitObject.ApplyDefaults(workingBeatmap.Value.Beatmap.ControlPointInfo, workingBeatmap.Value.Beatmap.BeatmapInfo.BaseDifficulty);
         }
 
+        private bool placementBegun;
+
         /// <summary>
-        /// Finishes the placement of <see cref="HitObject"/>.
+        /// Signals that the placement of <see cref="HitObject"/> has started.
         /// </summary>
-        public void Finish() => PlacementFinished?.Invoke(HitObject);
+        protected void BeginPlacement()
+        {
+            PlacementStarted?.Invoke(HitObject);
+            placementBegun = true;
+        }
+
+        /// <summary>
+        /// Signals that the placement of <see cref="HitObject"/> has finished.
+        /// This will destroy this <see cref="PlacementMask"/>, and add the <see cref="HitObject"/> to the <see cref="Beatmap"/>.
+        /// </summary>
+        protected void EndPlacement()
+        {
+            if (!placementBegun)
+                BeginPlacement();
+            PlacementFinished?.Invoke(HitObject);
+        }
 
         public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => Parent?.ReceivePositionalInputAt(screenSpacePos) ?? false;
 
@@ -64,6 +86,7 @@ namespace osu.Game.Rulesets.Edit
         {
             base.Dispose(isDisposing);
 
+            PlacementStarted = null;
             PlacementFinished = null;
         }
     }