From 2deea1b4d02e811c64e9d827e5c9336871ca3219 Mon Sep 17 00:00:00 2001
From: Devin Lin <espidev@gmail.com>
Date: Sun, 10 Apr 2022 13:28:32 -0400
Subject: [PATCH] components: Port Direction enum to c++ to improve load times

According to flame graph testing with qmlprofiler, this caused quite some overhead in QML.
---
 components/mobileshell/CMakeLists.txt          |  1 +
 .../mobileshell/components/direction.cpp       |  7 +++++++
 components/mobileshell/components/direction.h  | 18 ++++++++++++++++++
 components/mobileshell/mobileshellplugin.cpp   | 10 +++++++---
 .../qml/actiondrawer/ActionDrawer.qml          | 14 ++++++--------
 .../mobileshell/qml/components/Direction.qml   | 18 ------------------
 components/mobileshell/resources.qrc           |  1 -
 7 files changed, 39 insertions(+), 30 deletions(-)
 create mode 100644 components/mobileshell/components/direction.cpp
 create mode 100644 components/mobileshell/components/direction.h
 delete mode 100644 components/mobileshell/qml/components/Direction.qml

diff --git a/components/mobileshell/CMakeLists.txt b/components/mobileshell/CMakeLists.txt
index d5d0af64..12bb431e 100644
--- a/components/mobileshell/CMakeLists.txt
+++ b/components/mobileshell/CMakeLists.txt
@@ -13,6 +13,7 @@ set(mobileshellplugin_SRCS
     savedquicksettingsmodel.cpp
     shellutil.cpp
     windowutil.cpp
+    components/direction.cpp
     notifications/notificationthumbnailer.cpp
     notifications/notificationfilemenu.cpp
     homescreen/applicationlistmodel.cpp
diff --git a/components/mobileshell/components/direction.cpp b/components/mobileshell/components/direction.cpp
new file mode 100644
index 00000000..d9ac1b27
--- /dev/null
+++ b/components/mobileshell/components/direction.cpp
@@ -0,0 +1,7 @@
+/*
+ *  SPDX-FileCopyrightText: 2022 Devin Lin <devin@kde.org>
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "direction.h"
diff --git a/components/mobileshell/components/direction.h b/components/mobileshell/components/direction.h
new file mode 100644
index 00000000..11375ce8
--- /dev/null
+++ b/components/mobileshell/components/direction.h
@@ -0,0 +1,18 @@
+/*
+ *  SPDX-FileCopyrightText: 2022 Devin Lin <devin@kde.org>
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#pragma once
+
+#include <QObject>
+
+class Direction : public QObject
+{
+    Q_OBJECT
+
+public:
+    enum Type { None = 0, Up, Down, Left, Right };
+    Q_ENUM(Type)
+};
diff --git a/components/mobileshell/mobileshellplugin.cpp b/components/mobileshell/mobileshellplugin.cpp
index 2545435e..d3444a45 100644
--- a/components/mobileshell/mobileshellplugin.cpp
+++ b/components/mobileshell/mobileshellplugin.cpp
@@ -9,6 +9,8 @@
 #include <QQmlContext>
 #include <QQuickItem>
 
+#include "components/direction.h"
+
 #include "notifications/notificationfilemenu.h"
 #include "notifications/notificationthumbnailer.h"
 
@@ -48,8 +50,8 @@ void MobileShellPlugin::registerTypes(const char *uri)
         return WindowUtil::instance();
     });
 
-    // taskswitcher
-    qmlRegisterType<DisplaysModel>(uri, 1, 0, "DisplaysModel");
+    // components
+    qmlRegisterType<Direction>(uri, 1, 0, "Direction");
 
     // homescreen
     qmlRegisterSingletonType<ApplicationListModel>(uri, 1, 0, "ApplicationListModel", [](QQmlEngine *, QJSEngine *) -> QObject * {
@@ -63,6 +65,9 @@ void MobileShellPlugin::registerTypes(const char *uri)
     qmlRegisterType<NotificationThumbnailer>(uri, 1, 0, "NotificationThumbnailer");
     qmlRegisterType<NotificationFileMenu>(uri, 1, 0, "NotificationFileMenu");
 
+    // taskswitcher
+    qmlRegisterType<DisplaysModel>(uri, 1, 0, "DisplaysModel");
+
     // qml modules
 
     // /actiondrawer
@@ -72,7 +77,6 @@ void MobileShellPlugin::registerTypes(const char *uri)
 
     // /components
     qmlRegisterType(resolvePath("components/BaseItem.qml"), uri, 1, 0, "BaseItem");
-    qmlRegisterType(resolvePath("components/Direction.qml"), uri, 1, 0, "Direction");
     qmlRegisterType(resolvePath("components/StartupFeedback.qml"), uri, 1, 0, "StartupFeedback");
     qmlRegisterType(resolvePath("components/VelocityCalculator.qml"), uri, 1, 0, "VelocityCalculator");
 
diff --git a/components/mobileshell/qml/actiondrawer/ActionDrawer.qml b/components/mobileshell/qml/actiondrawer/ActionDrawer.qml
index 034817ac..97adb547 100644
--- a/components/mobileshell/qml/actiondrawer/ActionDrawer.qml
+++ b/components/mobileshell/qml/actiondrawer/ActionDrawer.qml
@@ -15,8 +15,6 @@ import org.kde.plasma.components 3.0 as PlasmaComponents
 import org.kde.plasma.private.nanoshell 2.0 as NanoShell
 import org.kde.plasma.private.mobileshell 1.0 as MobileShell
 
-import "../components" as Components
-
 Item {
     id: root
     
@@ -60,7 +58,7 @@ Item {
     /**
      * Direction the panel is currently moving in.
      */
-    property int direction: Components.Direction.None
+    property int direction: MobileShell.Direction.None
     
     /**
      * The mode of the action drawer (portrait or landscape).
@@ -111,8 +109,8 @@ Item {
             offset = 0;
         }
         root.direction = (oldOffset === offset) 
-                            ? Components.Direction.None 
-                            : (offset > oldOffset ? Components.Direction.Down : Components.Direction.Up);
+                            ? MobileShell.Direction.None 
+                            : (offset > oldOffset ? MobileShell.Direction.Down : MobileShell.Direction.Up);
             
         oldOffset = offset;
         
@@ -152,7 +150,7 @@ Item {
             // close immediately, so that we don't have to wait PlasmaCore.Units.longDuration 
             root.visible = false;
             close();
-        } else if (root.direction === Components.Direction.None || !root.opened) {
+        } else if (root.direction === MobileShell.Direction.None || !root.opened) {
             if (root.offset < openThreshold) {
                 close();
             } else {
@@ -161,12 +159,12 @@ Item {
         } else if (root.offset > contentContainerLoader.maximizedQuickSettingsOffset) {
             expand();
         } else if (root.offset > contentContainerLoader.minimizedQuickSettingsOffset) {
-            if (root.direction === Components.Direction.Down) {
+            if (root.direction === MobileShell.Direction.Down) {
                 expand();
             } else {
                 open();
             }
-        } else if (root.direction === Components.Direction.Down) {
+        } else if (root.direction === MobileShell.Direction.Down) {
             open();
         } else {
             close();
diff --git a/components/mobileshell/qml/components/Direction.qml b/components/mobileshell/qml/components/Direction.qml
deleted file mode 100644
index 64ae70bd..00000000
--- a/components/mobileshell/qml/components/Direction.qml
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- *  SPDX-FileCopyrightText: 2021 Devin Lin <devin@kde.org>
- *
- *  SPDX-License-Identifier: GPL-2.0-or-later
- */
-
-import QtQuick 2.15
-
-QtObject {
-    enum Type {
-        None = 0,
-        Up,
-        Down,
-        Left,
-        Right
-    }
-}
-
diff --git a/components/mobileshell/resources.qrc b/components/mobileshell/resources.qrc
index db01c0cd..23a9f1e8 100644
--- a/components/mobileshell/resources.qrc
+++ b/components/mobileshell/resources.qrc
@@ -21,7 +21,6 @@
         <file>qml/actiondrawer/PortraitContentContainer.qml</file>
         
         <file>qml/components/BaseItem.qml</file>
-        <file>qml/components/Direction.qml</file>
         <file>qml/components/StartupFeedback.qml</file>
         <file>qml/components/util.js</file>
         <file>qml/components/VelocityCalculator.qml</file>