Add window decoration to ShellClient

If a ShellClient supports the ServerSideDecoration interface we can
create a server decoration for it. For that updateDecoration is added
as a pure virtual method in AbstractClient and a more-or-less code copy
from Client is added to ShellClient.

Geometry handling is adjusted to consider the window decoration offsets.

abstract_client.h

@@ -523,6 +523,11 @@ public:
     bool processDecorationButtonPress(QMouseEvent *event, bool ignoreMenu = false);
     void processDecorationButtonRelease(QMouseEvent *event);
 
+    /**
+     * TODO: fix boolean traps
+     **/
+    virtual void updateDecoration(bool check_workspace_pos, bool force = false) = 0;
+
     /**
     * Returns whether the window provides context help or not. If it does,
     * you should show a help menu item or a help button like '?' and call

client.h

@@ -209,7 +209,7 @@ public:
 
     void takeFocus() override;
 
-    void updateDecoration(bool check_workspace_pos, bool force = false);
+    void updateDecoration(bool check_workspace_pos, bool force = false) override;
 
     void updateShape();
 

shell_client.cpp

@@ -26,6 +26,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "workspace.h"
 #include "virtualdesktops.h"
 #include "workspace.h"
+#include "decorations/decorationbridge.h"
+#include "decorations/decoratedclient.h"
+#include <KDecoration2/Decoration>
+#include <KDecoration2/DecoratedClient>
 
 #include <KWayland/Client/surface.h>
 #include <KWayland/Server/seat_interface.h>
@@ -78,7 +82,7 @@ ShellClient::ShellClient(ShellSurfaceInterface *surface)
     connect(surface->surface(), &SurfaceInterface::sizeChanged, this,
         [this] {
             m_clientSize = m_shellSurface->surface()->buffer()->size();
-            doSetGeometry(QRect(geom.topLeft(), m_clientSize));
+            doSetGeometry(QRect(geom.topLeft(), m_clientSize + QSize(borderLeft() + borderRight(), borderTop() + borderBottom())));
             discardWindowPixmap();
         }
     );
@@ -153,6 +157,8 @@ ShellClient::ShellClient(ShellSurfaceInterface *surface)
     if (ServerSideDecorationInterface *deco = ServerSideDecorationInterface::get(surface->surface())) {
         installServerSideDecoration(deco);
     }
+
+    updateColorScheme(QString());
 }
 
 ShellClient::~ShellClient() = default;
@@ -165,6 +171,7 @@ void ShellClient::destroyClient()
         del = Deleted::create(this);
     }
     emit windowClosed(this, del);
+    destroyDecoration();
 
     if (workspace()) {
         StackingUpdatesBlocker blocker(workspace());
@@ -276,7 +283,7 @@ void ShellClient::addDamage(const QRegion &damage)
             position = m_positionAfterResize.point();
             m_positionAfterResize.clear();
         }
-        doSetGeometry(QRect(position, m_clientSize));
+        doSetGeometry(QRect(position, m_clientSize + QSize(borderLeft() + borderRight(), borderTop() + borderBottom())));
     }
     markAsMapped();
     setDepth(m_shellSurface->surface()->buffer()->hasAlphaChannel() ? 32 : 24);
@@ -301,11 +308,56 @@ void ShellClient::markAsMapped()
     if (!m_unmapped) {
         return;
     }
+
     m_unmapped = false;
     setReadyForPainting();
     setupWindowManagementInterface();
 }
 
+void ShellClient::createDecoration(const QRect &oldGeom)
+{
+    KDecoration2::Decoration *decoration = Decoration::DecorationBridge::self()->createDecoration(this);
+    if (decoration) {
+        QMetaObject::invokeMethod(decoration, "update", Qt::QueuedConnection);
+        connect(decoration, &KDecoration2::Decoration::shadowChanged, this, &Toplevel::getShadow);
+        connect(decoration, &KDecoration2::Decoration::bordersChanged, this,
+            [this]() {
+                GeometryUpdatesBlocker blocker(this);
+                QRect oldgeom = geometry();
+                if (!isShade())
+                    checkWorkspacePosition(oldgeom);
+                emit geometryShapeChanged(this, oldgeom);
+            }
+        );
+    }
+    setDecoration(decoration);
+
+    emit geometryShapeChanged(this, oldGeom);
+}
+
+void ShellClient::updateDecoration(bool check_workspace_pos, bool force)
+{
+    if (!force &&
+            ((!isDecorated() && noBorder()) || (isDecorated() && !noBorder())))
+        return;
+    QRect oldgeom = geometry();
+    QRect oldClientGeom = oldgeom.adjusted(borderLeft(), borderTop(), -borderRight(), -borderBottom());
+    blockGeometryUpdates(true);
+    if (force)
+        destroyDecoration();
+    if (!noBorder()) {
+        createDecoration(oldgeom);
+    } else
+        destroyDecoration();
+    if (m_serverDecoration && isDecorated()) {
+        m_serverDecoration->setMode(KWayland::Server::ServerSideDecorationManagerInterface::Mode::Server);
+    }
+    getShadow();
+    if (check_workspace_pos)
+        checkWorkspacePosition(oldgeom, -2, oldClientGeom);
+    blockGeometryUpdates(false);
+}
+
 void ShellClient::setGeometry(int x, int y, int w, int h, ForceGeometry_t force)
 {
     Q_UNUSED(force)
@@ -339,6 +391,7 @@ void ShellClient::doSetGeometry(const QRect &rect)
     if (!m_unmapped) {
         addWorkspaceRepaint(visibleRect());
     }
+    triggerDecorationRepaint();
     emit geometryShapeChanged(this, old);
 }
 
@@ -492,6 +545,14 @@ MaximizeMode ShellClient::maximizeMode() const
 
 bool ShellClient::noBorder() const
 {
+    if (isInternal()) {
+        return true;
+    }
+    if (m_serverDecoration) {
+        if (m_serverDecoration->mode() == ServerSideDecorationManagerInterface::Mode::Server) {
+            return m_userNoBorder;
+        }
+    }
     return true;
 }
 
@@ -509,7 +570,16 @@ void ShellClient::setFullScreen(bool set, bool user)
 
 void ShellClient::setNoBorder(bool set)
 {
-    Q_UNUSED(set)
+    if (!userCanSetNoBorder()) {
+        return;
+    }
+    set = rules()->checkNoBorder(set);
+    if (m_userNoBorder == set) {
+        return;
+    }
+    m_userNoBorder = set;
+    updateDecoration(true, false);
+    updateWindowRules(Rules::NoBorder);
 }
 
 void ShellClient::setOnAllActivities(bool set)
@@ -662,7 +732,7 @@ xcb_window_t ShellClient::window() const
 void ShellClient::requestGeometry(const QRect &rect)
 {
     m_positionAfterResize.setPoint(rect.topLeft());
-    m_shellSurface->requestSize(rect.size());
+    m_shellSurface->requestSize(rect.size() - QSize(borderLeft() + borderRight(), borderTop() + borderBottom()));
 }
 
 void ShellClient::clientFullScreenChanged(bool fullScreen)
@@ -717,7 +787,7 @@ void ShellClient::installPlasmaShellSurface(PlasmaShellSurfaceInterface *surface
 {
     m_plasmaShellSurface = surface;
     auto updatePosition = [this, surface] {
-        doSetGeometry(QRect(surface->position(), m_clientSize));
+        doSetGeometry(QRect(surface->position(), m_clientSize + QSize(borderLeft() + borderRight(), borderTop() + borderBottom())));
     };
     auto updateRole = [this, surface] {
         NET::WindowType type = NET::Unknown;
@@ -860,18 +930,20 @@ void ShellClient::installServerSideDecoration(KWayland::Server::ServerSideDecora
     m_serverDecoration = deco;
     connect(m_serverDecoration, &ServerSideDecorationInterface::destroyed, this,
         [this] {
-            // TODO: update decoration
             m_serverDecoration = nullptr;
+            updateDecoration(true);
         }
     );
-    // TODO: update decoration
+    if (!m_unmapped) {
+        updateDecoration(true);
+    }
     connect(m_serverDecoration, &ServerSideDecorationInterface::modeRequested, this,
         [this] (ServerSideDecorationManagerInterface::Mode mode) {
             const bool changed = mode != m_serverDecoration->mode();
             // always acknowledge the requested mode
             m_serverDecoration->setMode(mode);
-            if (changed) {
-                // TODO: update decoration
+            if (changed && !m_unmapped) {
+                updateDecoration(false);
             }
         }
     );

shell_client.h

@@ -81,6 +81,7 @@ public:
     const WindowRules *rules() const override;
     void setFullScreen(bool set, bool user = true) override;
     void setNoBorder(bool set) override;
+    void updateDecoration(bool check_workspace_pos, bool force = false) override;
     void setOnAllActivities(bool set) override;
     void setShortcut(const QString &cut) override;
     const QKeySequence &shortcut() const override;
@@ -139,6 +140,7 @@ private Q_SLOTS:
 private:
     void requestGeometry(const QRect &rect);
     void doSetGeometry(const QRect &rect);
+    void createDecoration(const QRect &oldgeom);
     void destroyClient();
     void unmap();
     void createWindowId();
@@ -164,6 +166,7 @@ private:
     QPointer<KWayland::Server::PlasmaShellSurfaceInterface> m_plasmaShellSurface;
     QPointer<KWayland::Server::QtExtendedSurfaceInterface> m_qtExtendedSurface;
     KWayland::Server::ServerSideDecorationInterface *m_serverDecoration = nullptr;
+    bool m_userNoBorder = false;
     bool m_fullScreen = false;
     bool m_transient = false;
 };

workspace.cpp

@@ -372,6 +372,7 @@ void Workspace::init()
     if (auto w = waylandServer()) {
         connect(w, &WaylandServer::shellClientAdded, this,
             [this] (ShellClient *c) {
+                c->updateDecoration(false);
                 updateClientLayer(c);
                 if (!c->isInternal()) {
                     QRect area = clientArea(PlacementArea, Screens::self()->current(), c->desktop());