IMovieSession - remove CurrentInput and PreviousInput and move the logic to the one tool that utilizes them. Since these are purely derivable convenience properties, it's better to not be in the spec. If other other needs to do this logic we can move this out to an extension method

src/BizHawk.Client.Common/movie/MovieSession.cs

@@ -50,32 +50,6 @@ namespace BizHawk.Client.Common
 
 		public MultitrackRecorder MultiTrack { get; } = new MultitrackRecorder();
 
-		public IController CurrentInput
-		{
-			get
-			{
-				if (Movie.IsPlayingOrRecording() && Movie.Emulator.Frame > 0)
-				{
-					return Movie.GetInputState(Movie.Emulator.Frame - 1);
-				}
-
-				return null;
-			}
-		}
-
-		public IController PreviousFrame
-		{
-			get
-			{
-				if (Movie.IsPlayingOrRecording() && Movie.Emulator.Frame > 1)
-				{
-					return Movie.GetInputState(Movie.Emulator.Frame - 2);
-				}
-
-				return null;
-			}
-		}
-
 		public void RecreateMovieController(ControllerDefinition definition)
 		{
 			MovieController = new Bk2Controller(definition);

src/BizHawk.Client.Common/movie/interfaces/IMovieSession.cs

@@ -23,13 +23,6 @@ namespace BizHawk.Client.Common
 		IMovieController MovieController { get; }
 		MultitrackRecorder MultiTrack { get; }
 
-		/// <summary>
-		/// Gets the controller state from the movie for the most recent frame
-		/// </summary>
-		IController CurrentInput { get; }
-
-		IController PreviousFrame { get; }
-
 		/// <summary>
 		/// Recreates MovieController with the given controller definition
 		/// with an empty controller state

src/BizHawk.Client.EmuHawk/tools/VirtualPads/VirtualpadsTool.cs

@@ -149,14 +149,16 @@ namespace BizHawk.Client.EmuHawk
 			if (MovieSession.Movie.IsPlaying())
 			{
 				Readonly = true;
-				if (MovieSession.CurrentInput != null)
+				var currentInput = CurrentInput();
+				if (currentInput != null)
 				{
-					Pads.ForEach(p => p.Set(MovieSession.CurrentInput));
+					Pads.ForEach(p => p.Set(currentInput));
 				}
 			}
 			else if (MovieSession.Movie.IsRecording())
 			{
-				Pads.ForEach(p => p.SetPrevious(MovieSession.PreviousFrame));
+				var previousFrame = PreviousFrame();
+				Pads.ForEach(p => p.SetPrevious(previousFrame));
 				Readonly = false;
 			}
 
@@ -168,6 +170,26 @@ namespace BizHawk.Client.EmuHawk
 			Pads.ForEach(pad => pad.UpdateValues());
 		}
 
+		private IController CurrentInput()
+		{
+			if (MovieSession.Movie.IsPlayingOrRecording() && Emulator.Frame > 0)
+			{
+				return MovieSession.Movie.GetInputState(Emulator.Frame - 1);
+			}
+
+			return null;
+		}
+
+		public IController PreviousFrame()
+		{
+			if (MovieSession.Movie.IsPlayingOrRecording() && Emulator.Frame > 1)
+			{
+				return MovieSession.Movie.GetInputState(Emulator.Frame - 2);
+			}
+
+			return null;
+		}
+
 		protected override void FastUpdateAfter()
 		{
 			// TODO: SetPrevious logic should go here too or that will get out of whack