wayland: Expose tiled state to xdg-shell clients

A client-side decorated window could use this information to improve
management of edges, for example by providing inset resize handles, etc.

abstract_client.cpp

@@ -955,6 +955,7 @@ bool AbstractClient::startMoveResize()
         // Exit quick tile mode when the user attempts to resize a tiled window
         updateQuickTileMode(QuickTileFlag::None); // Do so without restoring original geometry
         setGeometryRestore(frameGeometry());
+        doSetQuickTileMode();
         emit quickTileModeChanged();
     }
 
@@ -2864,6 +2865,7 @@ void AbstractClient::setQuickTileMode(QuickTileMode mode, bool keyboard)
             }
             setGeometryRestore(prev_geom_restore);
         }
+        doSetQuickTileMode();
         emit quickTileModeChanged();
         return;
     }
@@ -2894,6 +2896,7 @@ void AbstractClient::setQuickTileMode(QuickTileMode mode, bool keyboard)
             setMaximize(false, false);
         }
 
+        doSetQuickTileMode();
         emit quickTileModeChanged();
 
         return;
@@ -2973,9 +2976,14 @@ void AbstractClient::setQuickTileMode(QuickTileMode mode, bool keyboard)
         setFrameGeometry(geometryRestore(), geom_mode);
         checkWorkspacePosition(); // Just in case it's a different screen
     }
+    doSetQuickTileMode();
     emit quickTileModeChanged();
 }
 
+void AbstractClient::doSetQuickTileMode()
+{
+}
+
 void AbstractClient::sendToScreen(int newScreen)
 {
     newScreen = rules()->checkScreen(newScreen);

abstract_client.h

@@ -973,6 +973,7 @@ protected:
     virtual void doSetSkipPager();
     virtual void doSetSkipSwitcher();
     virtual void doSetDemandsAttention();
+    virtual void doSetQuickTileMode();
 
     void setupWindowManagementInterface();
     void destroyWindowManagementInterface();

xdgshellclient.cpp

@@ -938,6 +938,62 @@ void XdgToplevelClient::doSetMaximized()
     scheduleConfigure();
 }
 
+static Qt::Edges anchorsForQuickTileMode(QuickTileMode mode)
+{
+    if (mode == QuickTileMode(QuickTileFlag::None)) {
+        return Qt::Edges();
+    }
+
+    Qt::Edges anchors = Qt::LeftEdge | Qt::TopEdge | Qt::RightEdge | Qt::BottomEdge;
+
+    if ((mode & QuickTileFlag::Left) && !(mode & QuickTileFlag::Right)) {
+        anchors &= ~Qt::RightEdge;
+    }
+    if ((mode & QuickTileFlag::Right) && !(mode & QuickTileFlag::Left)) {
+        anchors &= ~Qt::LeftEdge;
+    }
+
+    if ((mode & QuickTileFlag::Top) && !(mode & QuickTileFlag::Bottom)) {
+        anchors &= ~Qt::BottomEdge;
+    }
+    if ((mode & QuickTileFlag::Bottom) && !(mode & QuickTileFlag::Top)) {
+        anchors &= ~Qt::TopEdge;
+    }
+
+    return anchors;
+}
+
+void XdgToplevelClient::doSetQuickTileMode()
+{
+    const Qt::Edges anchors = anchorsForQuickTileMode(quickTileMode());
+
+    if (anchors & Qt::LeftEdge) {
+        m_requestedStates |= XdgToplevelInterface::State::TiledLeft;
+    } else {
+        m_requestedStates &= ~XdgToplevelInterface::State::TiledLeft;
+    }
+
+    if (anchors & Qt::RightEdge) {
+        m_requestedStates |= XdgToplevelInterface::State::TiledRight;
+    } else {
+        m_requestedStates &= ~XdgToplevelInterface::State::TiledRight;
+    }
+
+    if (anchors & Qt::TopEdge) {
+        m_requestedStates |= XdgToplevelInterface::State::TiledTop;
+    } else {
+        m_requestedStates &= ~XdgToplevelInterface::State::TiledTop;
+    }
+
+    if (anchors & Qt::BottomEdge) {
+        m_requestedStates |= XdgToplevelInterface::State::TiledBottom;
+    } else {
+        m_requestedStates &= ~XdgToplevelInterface::State::TiledBottom;
+    }
+
+    scheduleConfigure();
+}
+
 bool XdgToplevelClient::doStartMoveResize()
 {
     if (moveResizePointerMode() != PositionCenter) {
@@ -1721,6 +1777,7 @@ void XdgToplevelClient::changeMaximize(bool horizontal, bool vertical, bool adju
             updateQuickTileMode(QuickTileFlag::None);
         }
         if (quickTileMode() != oldQuickTileMode) {
+            doSetQuickTileMode();
             emit quickTileModeChanged();
         }
         setFrameGeometry(workspace()->clientArea(MaximizeArea, this));
@@ -1729,6 +1786,7 @@ void XdgToplevelClient::changeMaximize(bool horizontal, bool vertical, bool adju
             updateQuickTileMode(QuickTileFlag::None);
         }
         if (quickTileMode() != oldQuickTileMode) {
+            doSetQuickTileMode();
             emit quickTileModeChanged();
         }
 

xdgshellclient.h

@@ -176,6 +176,7 @@ protected:
     void changeMaximize(bool horizontal, bool vertical, bool adjust) override;
     Layer layerForDock() const override;
     bool stateCompare() const override;
+    void doSetQuickTileMode() override;
 
 private:
     void handleWindowTitleChanged();