Input: Workaround some issues with some keys not being usable/bindabl…

…e as shortcuts (e.g Print Screen)

UI/Windows/GetKeyWindow.axaml.cs

@@ -13,9 +13,8 @@
 using Mesen.Config;
 using Mesen.Utilities;
 using Mesen.Localization;
-using Avalonia.Remote.Protocol.Input;
-using DynamicData;
 using Avalonia.Layout;
+using System.Diagnostics;
 
 namespace Mesen.Windows
 {
@@ -27,6 +26,9 @@ public class GetKeyWindow : MesenWindow
 		private TextBlock lblCurrentKey;
 		private bool _allowKeyboardOnly;
 
+		private Stopwatch _stopWatch = Stopwatch.StartNew();
+		private Dictionary<Key, long> _keyPressedStamp = new();
+
 		public string HintLabel { get; }
 		public bool SingleKeyMode { get; set; } = false;
 
@@ -71,16 +73,31 @@ private void OnPreviewKeyDown(object? sender, KeyEventArgs e)
 		{
 			InputApi.SetKeyState((UInt16)e.Key, true);
 			DbgShortcutKey = new DbgShortKeys(e.KeyModifiers, e.Key);
+			_keyPressedStamp[e.Key] = _stopWatch.ElapsedTicks;
 			e.Handled = true;
 		}
 
 		private void OnPreviewKeyUp(object? sender, KeyEventArgs e)
 		{
+			e.Handled = true;
+
+			if(!_allowKeyboardOnly && (!_keyPressedStamp.TryGetValue(e.Key, out long stamp) || ((_stopWatch.ElapsedTicks - stamp) * 1000 / Stopwatch.Frequency) < 10)) {
+				//Key up received without key down, or key pressed for less than 10 ms, pretend the key was pressed for 50ms
+				//Some special keys can behave this way (e.g printscreen)
+				DbgShortcutKey = new DbgShortKeys(e.KeyModifiers, e.Key);
+				InputApi.SetKeyState((UInt16)e.Key, true);
+				UpdateKeyDisplay();
+				DispatcherTimer.RunOnce(() => InputApi.SetKeyState((UInt16)e.Key, false), TimeSpan.FromMilliseconds(50), DispatcherPriority.MaxValue);
+				_keyPressedStamp.Remove(e.Key);
+				return;
+			}
+
+			_keyPressedStamp.Remove(e.Key);
+
 			InputApi.SetKeyState((UInt16)e.Key, false);
 			if(_allowKeyboardOnly) {
 				this.Close();
 			}
-			e.Handled = true;
 		}
 
 		protected override void OnOpened(EventArgs e)

UI/Windows/MainWindow.axaml.cs

@@ -22,6 +22,7 @@
 using System.Collections.Generic;
 using Mesen.Controls;
 using Mesen.Localization;
+using System.Diagnostics;
 
 namespace Mesen.Windows
 {
@@ -58,6 +59,9 @@ public class MainWindow : MesenWindow
 		private Dictionary<Key, IDisposable> _pendingKeyUpEvents = new();
 		private bool _isLinux = false;
 
+		private Stopwatch _stopWatch = Stopwatch.StartNew();
+		private Dictionary<Key, long> _keyPressedStamp = new();
+
 		static MainWindow()
 		{
 			WindowStateProperty.Changed.AddClassHandler<MainWindow>((x, e) => x.OnWindowStateChanged());
@@ -558,11 +562,6 @@ private bool ProcessTestModeShortcuts(Key key)
 			return false;
 		}
 
-		private static bool IsModifierKey(Key key)
-		{
-			return key == Key.LeftShift || key == Key.LeftCtrl || key == Key.LeftAlt || key == Key.RightShift || key == Key.RightCtrl || key == Key.RightAlt;
-		}
-
 		private void OnPreviewKeyDown(object? sender, KeyEventArgs e)
 		{
 			if(_testModeEnabled && e.KeyModifiers == KeyModifiers.Alt && ProcessTestModeShortcuts(e.Key)) {
@@ -575,6 +574,8 @@ private void OnPreviewKeyDown(object? sender, KeyEventArgs e)
 			}
 
 			if(e.Key != Key.None) {
+				_keyPressedStamp[e.Key] = _stopWatch.ElapsedTicks;
+
 				if(_isLinux && _pendingKeyUpEvents.TryGetValue(e.Key, out IDisposable? cancelTimer)) {
 					//Cancel any pending key up event
 					cancelTimer.Dispose();
@@ -598,6 +599,17 @@ private void OnPreviewKeyUp(object? sender, KeyEventArgs e)
 			}
 
 			if(e.Key != Key.None) {
+				if(!_keyPressedStamp.TryGetValue(e.Key, out long stamp) || ((_stopWatch.ElapsedTicks - stamp) * 1000 / Stopwatch.Frequency) < 10) {
+					//Key up received without key down, or key pressed for less than 10 ms, pretend the key was pressed for 50ms
+					//Some special keys can behave this way (e.g printscreen)
+					InputApi.SetKeyState((UInt16)e.Key, true);
+					DispatcherTimer.RunOnce(() => InputApi.SetKeyState((UInt16)e.Key, false), TimeSpan.FromMilliseconds(50), DispatcherPriority.MaxValue);
+					_keyPressedStamp.Remove(e.Key);
+					return;
+				}
+
+				_keyPressedStamp.Remove(e.Key);
+
 				if(_isLinux) {
 					//Process keyup events after 1ms on Linux to prevent key repeat from triggering key up/down repeatedly
 					IDisposable cancelTimer = DispatcherTimer.RunOnce(() => InputApi.SetKeyState((UInt16)e.Key, false), TimeSpan.FromMilliseconds(1), DispatcherPriority.MaxValue);