From a30d8ba768a24d2398ec6279e9296aba37548a5c Mon Sep 17 00:00:00 2001
From: Nikita Tsukanov <keks9n@gmail.com>
Date: Wed, 16 Nov 2022 17:55:15 +0600
Subject: [PATCH] [X11] Skip TextInput event if KeyDown event was handled

---
 src/Avalonia.X11/X11Window.Ime.cs | 50 ++++++++++++++++++++-----------
 src/Avalonia.X11/X11Window.cs     | 10 +++++--
 2 files changed, 40 insertions(+), 20 deletions(-)

diff --git a/src/Avalonia.X11/X11Window.Ime.cs b/src/Avalonia.X11/X11Window.Ime.cs
index d68feaca78..ca987d0a07 100644
--- a/src/Avalonia.X11/X11Window.Ime.cs
+++ b/src/Avalonia.X11/X11Window.Ime.cs
@@ -8,6 +8,7 @@ using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Input.TextInput;
 using Avalonia.Platform.Interop;
+using JetBrains.Annotations;
 using static Avalonia.X11.XLib;
 
 namespace Avalonia.X11
@@ -104,13 +105,18 @@ namespace Avalonia.X11
             if (ev.KeyEvent.state.HasAllFlags(XModifierMask.Mod2Mask)
                 && key > X11Key.Num_Lock && key <= X11Key.KP_9)
                 key = (X11Key)XKeycodeToKeysym(_x11.Display, ev.KeyEvent.keycode, index ? 0 : 1).ToInt32();
-            
-            var filtered = ScheduleKeyInput(new RawKeyEventArgs(_keyboard, (ulong)ev.KeyEvent.time.ToInt64(), _inputRoot,
-                ev.type == XEventName.KeyPress ? RawKeyEventType.KeyDown : RawKeyEventType.KeyUp,
-                X11KeyTransform.ConvertKey(key), TranslateModifiers(ev.KeyEvent.state)), ref ev, (int)key, ev.KeyEvent.keycode);
-           
-            if (ev.type == XEventName.KeyPress && !filtered) 
-                TriggerClassicTextInputEvent(ref ev);
+
+            var convertedKey = X11KeyTransform.ConvertKey(key);
+            var modifiers = TranslateModifiers(ev.KeyEvent.state);
+            var timestamp = (ulong)ev.KeyEvent.time.ToInt64();
+            RawKeyEventArgs args =
+                ev.type == XEventName.KeyPress
+                    ? new RawKeyEventArgsWithText(_keyboard, timestamp, _inputRoot, RawKeyEventType.KeyDown,
+                        convertedKey, modifiers, TranslateEventToString(ref ev))
+                    : new RawKeyEventArgs(_keyboard, timestamp, _inputRoot, RawKeyEventType.KeyUp, convertedKey,
+                        modifiers);
+
+            ScheduleKeyInput(args, ref ev, (int)key, ev.KeyEvent.keycode);
         }
 
         void TriggerClassicTextInputEvent(ref XEvent ev)
@@ -156,16 +162,15 @@ namespace Avalonia.X11
         }
         
         
-        bool ScheduleKeyInput(RawKeyEventArgs args, ref XEvent xev, int keyval, int keycode)
+        void ScheduleKeyInput(RawKeyEventArgs args, ref XEvent xev, int keyval, int keycode)
         {
             _x11.LastActivityTimestamp = xev.ButtonEvent.time;
-            if (_imeControl != null && _imeControl.IsEnabled)
-            {
-                if (FilterIme(args, xev, keyval, keycode))
-                    return true;
-            }
+            
+            if (_imeControl is { IsEnabled: true } 
+                && FilterIme(args, xev, keyval, keycode)) 
+                return;
+            
             ScheduleInput(args);
-            return false;
         }
         
         bool FilterIme(RawKeyEventArgs args, XEvent xev, int keyval, int keycode)
@@ -190,11 +195,7 @@ namespace Avalonia.X11
                 {
                     var ev = _imeQueue.Dequeue();
                     if (_imeControl == null || !await _imeControl.HandleEventAsync(ev.args, ev.keyval, ev.keycode))
-                    {
                         ScheduleInput(ev.args);
-                        if (ev.args.Type == RawKeyEventType.KeyDown)
-                            TriggerClassicTextInputEvent(ref ev.xev);
-                    }
                 }
             }
             finally
@@ -202,5 +203,18 @@ namespace Avalonia.X11
                 _processingIme = false;
             }
         }
+
+        // This class is used to attach the text value of the key to an asynchronously dispatched KeyDown event
+        class RawKeyEventArgsWithText : RawKeyEventArgs
+        {
+            public RawKeyEventArgsWithText([NotNull] IKeyboardDevice device, ulong timestamp, [NotNull] IInputRoot root,
+                RawKeyEventType type, Key key, RawInputModifiers modifiers, string text) :
+                base(device, timestamp, root, type, key, modifiers)
+            {
+                Text = text;
+            }
+            
+            public string Text { get; }
+        }
     }
 }
diff --git a/src/Avalonia.X11/X11Window.cs b/src/Avalonia.X11/X11Window.cs
index 690ac0ebce..0b5ae281f4 100644
--- a/src/Avalonia.X11/X11Window.cs
+++ b/src/Avalonia.X11/X11Window.cs
@@ -190,7 +190,7 @@ namespace Avalonia.X11
             UpdateMotifHints();
             UpdateSizeHints(null);
 
-            _rawEventGrouper = new RawEventGrouper(e => Input?.Invoke(e));
+            _rawEventGrouper = new RawEventGrouper(DispatchInput);
             
             _transparencyHelper = new TransparencyHelper(_x11, _handle, platform.Globals);
             _transparencyHelper.SetTransparencyRequest(WindowTransparencyLevel.None);
@@ -724,7 +724,13 @@ namespace Avalonia.X11
             _x11.LastActivityTimestamp = xev.ButtonEvent.time;
             ScheduleInput(args);
         }
-        
+
+        void DispatchInput(RawInputEventArgs args)
+        {
+            Input?.Invoke(args);
+            if (!args.Handled && args is RawKeyEventArgsWithText text && !string.IsNullOrWhiteSpace(text.Text))
+                Input?.Invoke(new RawTextInputEventArgs(_keyboard, args.Timestamp, _inputRoot, text.Text));
+        }
 
         public void ScheduleXI2Input(RawInputEventArgs args)
         {