From 11f6292cb5d9d44d043ea24de95bac0873423a7d Mon Sep 17 00:00:00 2001
From: Weng Xuetian <wengxt@gmail.com>
Date: Mon, 13 Dec 2021 09:23:23 -0800
Subject: [PATCH] Move input keyboard filter to be just before the key is sent
 to application.

Features like global shortcuts should be handled before the input
method.
---
 src/input.cpp       | 20 ++++++++++++++++++++
 src/inputmethod.cpp | 27 +++++----------------------
 src/inputmethod.h   |  3 +++
 3 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/src/input.cpp b/src/input.cpp
index cd76b8e97c..5ca8d8bd51 100644
--- a/src/input.cpp
+++ b/src/input.cpp
@@ -18,6 +18,7 @@
 #include "input_event.h"
 #include "input_event_spy.h"
 #include "inputbackend.h"
+#include "inputmethod.h"
 #include "keyboard_input.h"
 #include "main.h"
 #include "pointer_input.h"
@@ -44,6 +45,7 @@
 #include <KGlobalAccel>
 #include <KLocalizedString>
 #include <KWaylandServer/display.h>
+#include <KWaylandServer/inputmethod_v1_interface.h>
 #include <KWaylandServer/seat_interface.h>
 #include <KWaylandServer/shmclientbuffer.h>
 #include <KWaylandServer/surface_interface.h>
@@ -1487,6 +1489,23 @@ public:
     }
 };
 
+class InputKeyboardFilter : public InputEventFilter
+{
+public:
+    bool keyEvent(QKeyEvent *event) override
+    {
+        if (auto keyboardGrab = InputMethod::self()->keyboardGrab()) {
+            if (event->isAutoRepeat()) {
+                return true;
+            }
+            auto newState = event->type() == QEvent::KeyPress ? KWaylandServer::KeyboardKeyState::Pressed : KWaylandServer::KeyboardKeyState::Released;
+            keyboardGrab->sendKey(waylandServer()->display()->nextSerial(), event->timestamp(), event->nativeScanCode(), newState);
+            return true;
+        }
+        return false;
+    }
+};
+
 /**
  * The remaining default input filter which forwards events to other windows
  */
@@ -2450,6 +2469,7 @@ void InputRedirection::setupInputFilters()
     installInputEventFilter(new DecorationEventFilter);
     installInputEventFilter(new WindowActionInputFilter);
     installInputEventFilter(new InternalWindowEventFilter);
+    installInputEventFilter(new InputKeyboardFilter);
     installInputEventFilter(new ForwardInputFilter);
     installInputEventFilter(new TabletInputFilter);
 }
diff --git a/src/inputmethod.cpp b/src/inputmethod.cpp
index 88b9ee5f16..12ce32958d 100644
--- a/src/inputmethod.cpp
+++ b/src/inputmethod.cpp
@@ -630,33 +630,16 @@ bool InputMethod::isActive() const
     return waylandServer()->inputMethod()->context();
 }
 
-class InputKeyboardFilter : public InputEventFilter {
-public:
-    InputKeyboardFilter(KWaylandServer::InputMethodGrabV1 *grab)
-        : m_keyboardGrab(grab)
-    {
-    }
-
-    bool keyEvent(QKeyEvent *event) override {
-        if (event->isAutoRepeat()) {
-            return true;
-        }
-        auto newState = event->type() == QEvent::KeyPress ? KWaylandServer::KeyboardKeyState::Pressed : KWaylandServer::KeyboardKeyState::Released;
-        m_keyboardGrab->sendKey(waylandServer()->display()->nextSerial(), event->timestamp(), event->nativeScanCode(), newState);
-        return true;
-    }
-    InputMethodGrabV1 *const m_keyboardGrab;
-};
+KWaylandServer::InputMethodGrabV1 *InputMethod::keyboardGrab()
+{
+    return isActive() ? m_keyboardGrab : nullptr;
+}
 
 void InputMethod::installKeyboardGrab(KWaylandServer::InputMethodGrabV1 *keyboardGrab)
 {
     auto xkb = input()->keyboard()->xkb();
-    auto filter = new InputKeyboardFilter(keyboardGrab);
+    m_keyboardGrab = keyboardGrab;
     keyboardGrab->sendKeymap(xkb->keymapContents());
-    input()->prependInputEventFilter(filter);
-    connect(keyboardGrab, &QObject::destroyed, input(), [filter] {
-        input()->uninstallInputEventFilter(filter);
-    });
 }
 
 void InputMethod::updateModifiersMap(const QByteArray &modifiers)
diff --git a/src/inputmethod.h b/src/inputmethod.h
index 6f06c663fe..578a268b7c 100644
--- a/src/inputmethod.h
+++ b/src/inputmethod.h
@@ -57,6 +57,8 @@ public:
     void setPanel(InputPanelV1Client* client);
     void setInputMethodCommand(const QString &path);
 
+    KWaylandServer::InputMethodGrabV1 *keyboardGrab();
+
 Q_SIGNALS:
     void activeChanged(bool active);
     void enabledChanged(bool enabled);
@@ -106,6 +108,7 @@ private:
     quint32 m_serial = 0;
     QPointer<InputPanelV1Client> m_inputClient;
     QPointer<AbstractClient> m_trackedClient;
+    QPointer<KWaylandServer::InputMethodGrabV1> m_keyboardGrab;
 
     QProcess *m_inputMethodProcess = nullptr;
     QTimer m_inputMethodCrashTimer;