From 501ff149cfc004941e2db132d72b45e507dd1872 Mon Sep 17 00:00:00 2001
From: Altair Wei <altair_wei@outlook.com>
Date: Mon, 20 Sep 2021 09:10:04 +0800
Subject: [PATCH] implemented X11 resizing

---
 framelesshelper.cpp | 13 +++++++++++-
 framelesshelper.h   |  1 +
 utilities.h         |  4 +++-
 utilities_linux.cpp | 52 ++++++++++++++++++++++++++++++++++++++++-----
 4 files changed, 63 insertions(+), 7 deletions(-)

diff --git a/framelesshelper.cpp b/framelesshelper.cpp
index 336d583..79f5a12 100644
--- a/framelesshelper.cpp
+++ b/framelesshelper.cpp
@@ -243,13 +243,23 @@ void FramelessHelper::updateHoverStates(const QPoint& pos)
 void FramelessHelper::startMove(QMouseEvent* event)
 {
 #ifdef Q_OS_LINUX
-    Utilities::sendX11ButtonRelease(m_window, event->globalPos());
+    Utilities::sendX11ButtonReleaseEvent(m_window, event->globalPos());
     Utilities::startX11Moving(m_window, event->globalPos());
     event->accept();
     return;
 #endif
 }
 
+void FramelessHelper::startResize(QMouseEvent* event, Qt::WindowFrameSection frameSection)
+{
+#ifdef Q_OS_LINUX
+    Utilities::sendX11ButtonReleaseEvent(m_window, event->globalPos());
+    Utilities::startX11Resizing(m_window, event->globalPos(), frameSection);
+    event->accept();
+    return;
+#endif
+}
+
 bool FramelessHelper::eventFilter(QObject *object, QEvent *event)
 {
     bool filterOut = false;
@@ -277,6 +287,7 @@ bool FramelessHelper::eventFilter(QObject *object, QEvent *event)
             auto ev = static_cast<QMouseEvent *>(event);
             if (isHoverResizeHandler()) {
                 // Start system resize
+                startResize(ev, m_hoveredFrameSection);
                 filterOut = true;
             } else if (isInTitlebarArea(ev->pos())) {
                 // Start system move
diff --git a/framelesshelper.h b/framelesshelper.h
index 2654373..f6ef065 100644
--- a/framelesshelper.h
+++ b/framelesshelper.h
@@ -83,6 +83,7 @@ public:
     void updateHoverStates(const QPoint& pos);
 
     void startMove(QMouseEvent* event);
+    void startResize(QMouseEvent* event, Qt::WindowFrameSection frameSection);
 
 protected:
     bool eventFilter(QObject *object, QEvent *event) override;
diff --git a/utilities.h b/utilities.h
index 246f9b0..5e2786b 100644
--- a/utilities.h
+++ b/utilities.h
@@ -59,8 +59,10 @@ FRAMELESSHELPER_API void updateQtFrameMargins(QWindow *window, const bool enable
 #endif
 
 #ifdef Q_OS_LINUX
-FRAMELESSHELPER_API void sendX11ButtonRelease(QWindow *w, const QPoint &pos);
+FRAMELESSHELPER_API void sendX11ButtonReleaseEvent(QWindow *w, const QPoint &pos);
+FRAMELESSHELPER_API void sendX11MoveResizeEvent(QWindow *w, const QPoint &pos, int section);
 FRAMELESSHELPER_API void startX11Moving(QWindow *w, const QPoint &pos);
+FRAMELESSHELPER_API void startX11Resizing(QWindow *w, const QPoint &pos, Qt::WindowFrameSection frameSection);
 #endif
 
 }
diff --git a/utilities_linux.cpp b/utilities_linux.cpp
index 40e5609..6394a55 100644
--- a/utilities_linux.cpp
+++ b/utilities_linux.cpp
@@ -149,7 +149,7 @@ bool Utilities::showSystemMenu(const WId winId, const QPointF &pos)
     return false;
 }
 
-void Utilities::sendX11ButtonRelease(QWindow *w, const QPoint &pos)
+void Utilities::sendX11ButtonReleaseEvent(QWindow *w, const QPoint &pos)
 {
     QPoint clientPos = w->mapFromGlobal(pos);
     Display *display = QX11Info::display();
@@ -177,7 +177,7 @@ void Utilities::sendX11ButtonRelease(QWindow *w, const QPoint &pos)
     XFlush(display);
 }
 
-void Utilities::startX11Moving(QWindow *w, const QPoint &pos)
+void Utilities::sendX11MoveResizeEvent(QWindow *w, const QPoint &pos, int section)
 {
     Display *display = QX11Info::display();
     int screen = QX11Info::appScreen();
@@ -197,14 +197,56 @@ void Utilities::startX11Moving(QWindow *w, const QPoint &pos)
     event.xclient.format = 32;
     event.xclient.data.l[0] = pos.x();
     event.xclient.data.l[1] = pos.y();
-    event.xclient.data.l[2] = _NET_WM_MOVERESIZE_MOVE;
+    event.xclient.data.l[2] = section;
     event.xclient.data.l[3] = Button1;
-    event.xclient.data.l[4] = 0; /* unused */
+    event.xclient.data.l[4] = 0;
     if (XSendEvent(display, rootWindow,
         False, SubstructureRedirectMask | SubstructureNotifyMask, &event) == 0)
-        qWarning() << "Cant send Move event.";
+        qWarning("Cant send Move or Resize event.");
     XFlush(display);
 }
 
+void Utilities::startX11Moving(QWindow *w, const QPoint &pos)
+{
+    sendX11MoveResizeEvent(w, pos, _NET_WM_MOVERESIZE_MOVE);
+}
+
+void Utilities::startX11Resizing(QWindow *w, const QPoint &pos, Qt::WindowFrameSection frameSection)
+{
+    int section = -1;
+
+    switch (frameSection)
+    {
+    case Qt::LeftSection:
+        section = _NET_WM_MOVERESIZE_SIZE_LEFT;
+        break;
+    case Qt::TopLeftSection:
+        section = _NET_WM_MOVERESIZE_SIZE_TOPLEFT;
+        break;
+    case Qt::TopSection:
+        section = _NET_WM_MOVERESIZE_SIZE_TOP;
+        break;
+    case Qt::TopRightSection:
+        section = _NET_WM_MOVERESIZE_SIZE_TOPRIGHT;
+        break;
+    case Qt::RightSection:
+        section = _NET_WM_MOVERESIZE_SIZE_RIGHT;
+        break;
+    case Qt::BottomRightSection:
+        section = _NET_WM_MOVERESIZE_SIZE_BOTTOMRIGHT;
+        break;
+    case Qt::BottomSection:
+        section = _NET_WM_MOVERESIZE_SIZE_BOTTOM;
+        break;
+    case Qt::BottomLeftSection:
+        section = _NET_WM_MOVERESIZE_SIZE_BOTTOMLEFT;
+        break;
+    default:
+        break;
+    }
+
+    if (section != -1)
+        sendX11MoveResizeEvent(w, pos, section);
+}
 
 FRAMELESSHELPER_END_NAMESPACE
\ No newline at end of file