From e40cb6797df3896d6179dc0f85edef8168c5ee09 Mon Sep 17 00:00:00 2001
From: Christine Chen <chenchr@umich.edu>
Date: Sat, 17 Apr 2021 15:27:22 -0400
Subject: [PATCH] Use GetEndTime() to get storyboard endtime

---
 osu.Game/Storyboards/IStoryboardElement.cs          | 13 +++++++++++++
 .../Storyboards/IStoryboardElementHasDuration.cs    |  3 +++
 osu.Game/Storyboards/Storyboard.cs                  |  2 +-
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/osu.Game/Storyboards/IStoryboardElement.cs b/osu.Game/Storyboards/IStoryboardElement.cs
index c4c150a8a4..377ad57ab2 100644
--- a/osu.Game/Storyboards/IStoryboardElement.cs
+++ b/osu.Game/Storyboards/IStoryboardElement.cs
@@ -14,4 +14,17 @@ namespace osu.Game.Storyboards
 
         Drawable CreateDrawable();
     }
+
+    public static class StoryboardElementExtensions
+    {
+        /// <summary>
+        /// Returns the end time of this object.
+        /// </summary>
+        /// <remarks>
+        /// This returns the <see cref="IStoryboardElementHasDuration.EndTime"/> where available, falling back to <see cref="IStoryboardElement.StartTime"/> otherwise.
+        /// </remarks>
+        /// <param name="storyboardElement">The object.</param>
+        /// <returns>The end time of this object.</returns>
+        public static double GetEndTime(this IStoryboardElement storyboardElement) => (storyboardElement as IStoryboardElementHasDuration)?.EndTime ?? storyboardElement.StartTime;
+    }
 }
diff --git a/osu.Game/Storyboards/IStoryboardElementHasDuration.cs b/osu.Game/Storyboards/IStoryboardElementHasDuration.cs
index e6ee373812..daa0c55704 100644
--- a/osu.Game/Storyboards/IStoryboardElementHasDuration.cs
+++ b/osu.Game/Storyboards/IStoryboardElementHasDuration.cs
@@ -3,6 +3,9 @@
 
 namespace osu.Game.Storyboards
 {
+    /// <summary>
+    /// A StoryboardElement that ends at a different time than its start time.
+    /// </summary>
     public interface IStoryboardElementHasDuration
     {
         double EndTime { get; }
diff --git a/osu.Game/Storyboards/Storyboard.cs b/osu.Game/Storyboards/Storyboard.cs
index 0b02a4921b..bc61f704dd 100644
--- a/osu.Game/Storyboards/Storyboard.cs
+++ b/osu.Game/Storyboards/Storyboard.cs
@@ -44,7 +44,7 @@ namespace osu.Game.Storyboards
         /// This iterates all elements and as such should be used sparingly or stored locally.
         /// Videos and samples return StartTime as their EndTIme.
         /// </remarks>
-        public double? LatestEventTime => Layers.SelectMany(l => l.Elements.OfType<IStoryboardElementHasDuration>()).OrderByDescending(e => e.EndTime).FirstOrDefault()?.EndTime;
+        public double? LatestEventTime => Layers.SelectMany(l => l.Elements).OrderBy(e => e.GetEndTime()).LastOrDefault()?.GetEndTime();
 
         /// <summary>
         /// Depth of the currently front-most storyboard layer, excluding the overlay layer.