Use an unsigned type for IEmuClientApi.ShowFuture

fixes 6223c9d

Author: YoshiRulz

src/BizHawk.Client.Common/Api/Classes/EmuClientApi.cs

@@ -219,11 +219,11 @@ public void SetWindowSize(int size)
 			}
 		}
 
-		public void ShowFuture(ShowFutureCallback/*?*/ preFrameCallback, short maxFrames)
+		public void ShowFuture(ShowFutureCallback/*?*/ preFrameCallback, ushort maxFrames)
 		{
 			if (preFrameCallback is not null)
 			{
-				if (maxFrames <= 0) throw new ArgumentOutOfRangeException(paramName: nameof(maxFrames), maxFrames, message: "Invalid number of future frames, number must be positive.");
+				if (maxFrames is 0) throw new ArgumentOutOfRangeException(paramName: nameof(maxFrames), maxFrames, message: "0 frames is not in the future. Did you mean to disable this by passing (null, 0)?");
 				_mainForm.MaxFutureFrames = maxFrames;
 			}
 			else

src/BizHawk.Client.Common/Api/Interfaces/IEmuClientApi.cs

@@ -146,10 +146,10 @@ public interface IEmuClientApi : IDisposable, IExternalApi
 		/// <br/>Pass null to disable future frame display.</param>
 		/// <param name="maxFrames">The maximum number of future frames to emulate. Useful to avoid freezing the client UI in case of accidentally never returning true from the callback.</param>
 		/// <exception cref="ArgumentOutOfRangeException">
-		/// <paramref name="maxFrames"/> ≤ <c>0</c>
+		/// <paramref name="maxFrames"/> is <c>0</c>
 		/// (and <paramref name="preFrameCallback"/> is a delegate, since <paramref name="maxFrames"/> is ignored when it's <see langword="null"/>)
 		/// </exception>
-		void ShowFuture(ShowFutureCallback/*?*/ preFrameCallback, short maxFrames);
+		void ShowFuture(ShowFutureCallback/*?*/ preFrameCallback, ushort maxFrames);
 
 		void SpeedMode(int percent);
 

src/BizHawk.Client.Common/lua/CommonLibs/ClientLuaLibrary.cs

@@ -288,15 +288,15 @@ public void SetWindowSize(int size)
 				"the client UI in case of accidentally never returning true from the callback.")]
 		public string ShowFuture(LuaFunction luaf, long maxFrames, string name = null)
 		{
-			if (maxFrames < 1 || maxFrames > short.MaxValue)
+			if (maxFrames is < 1 or > ushort.MaxValue)
 			{
 				Log($"Invalid number of future frames ({maxFrames}); number must be positive and less than 2^15.");
 				return EventsLuaLibrary.EMPTY_UUID_STR;
 			}
 
 			INamedLuaFunction nlf = CreateAndRegisterNamedFunction(luaf, NamedLuaFunction.EVENT_TYPE_FUTURE, prohibitedApis: ApiGroup.PROHIBITED_MID_FRAME, name: name);
 			ShowFutureCallback FutureCallback = (f) => nlf.Call(f) is [ bool r ] ? r : false;
-			APIs.EmuClient.ShowFuture(FutureCallback, (short)maxFrames);
+			APIs.EmuClient.ShowFuture(FutureCallback, (ushort) maxFrames);
 			nlf.OnRemove += () => APIs.EmuClient.ShowFuture(null, 0);
 			return nlf.GuidStr;
 		}