manual drag override (#6461)

* manual drag override

* fix styles

* pr comments

* better close button rect calc

cockatrice/src/game/zones/view_zone_widget.cpp

@@ -13,12 +13,20 @@
 #include <QGraphicsLinearLayout>
 #include <QGraphicsProxyWidget>
 #include <QGraphicsSceneMouseEvent>
+#include <QGraphicsView>
 #include <QLabel>
 #include <QPainter>
 #include <QScrollBar>
+#include <QStyle>
 #include <QStyleOption>
 #include <libcockatrice/protocol/pb/command_shuffle.pb.h>
 
+namespace
+{
+constexpr qreal kTitleBarHeight = 24.0;
+constexpr qreal kMinVisibleWidth = 100.0;
+} // namespace
+
 /**
  * @param _player the player the cards were revealed to.
  * @param _origZone the zone the cards were revealed from.
@@ -241,33 +249,182 @@ void ZoneViewWidget::retranslateUi()
     pileViewCheckBox.setText(tr("pile view"));
 }
 
-void ZoneViewWidget::moveEvent(QGraphicsSceneMoveEvent * /* event */)
+void ZoneViewWidget::stopWindowDrag()
 {
-    if (!scene())
+    if (!draggingWindow)
         return;
 
-    int titleBarHeight = 24;
+    draggingWindow = false;
+    ungrabMouse();
+}
 
-    QPointF scenePos = pos();
+void ZoneViewWidget::startWindowDrag(QGraphicsSceneMouseEvent *event)
+{
+    draggingWindow = true;
+    dragStartItemPos = pos();
+    dragStartScreenPos = event->screenPos();
+    dragView = findDragView(event->widget());
 
-    if (scenePos.x() < 0) {
-        scenePos.setX(0);
-    } else {
-        qreal maxw = scene()->sceneRect().width() - 100;
-        if (scenePos.x() > maxw)
-            scenePos.setX(maxw);
+    // need to grab mouse to receive events and not miss initial movement
+    grabMouse();
+}
+
+QRectF ZoneViewWidget::closeButtonRect(QWidget *styleWidget) const
+{
+    const QRectF frameRectF = windowFrameRect();
+    const QRect titleBarRect(frameRectF.toRect().x(), frameRectF.toRect().y(), frameRectF.toRect().width(),
+                             static_cast<int>(kTitleBarHeight));
+
+    // query the style for the close button position (handles macOS top-left placement)
+    if (styleWidget) {
+        QStyleOptionTitleBar opt;
+        opt.initFrom(styleWidget);
+        opt.rect = titleBarRect;
+        opt.text = windowTitle();
+        opt.icon = styleWidget->windowIcon();
+        opt.titleBarFlags = Qt::Window | Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowCloseButtonHint;
+        opt.subControls = QStyle::SC_TitleBarCloseButton;
+        opt.activeSubControls = QStyle::SC_TitleBarCloseButton;
+        opt.titleBarState = styleWidget->isActiveWindow() ? Qt::WindowActive : Qt::WindowNoState;
+        if (styleWidget->isActiveWindow())
+            opt.state |= QStyle::State_Active;
+        const QRect r = styleWidget->style()->subControlRect(QStyle::CC_TitleBar, &opt, QStyle::SC_TitleBarCloseButton,
+                                                             styleWidget);
+        if (r.isValid() && !r.isEmpty()) {
+            return QRectF(r);
+        }
     }
 
-    if (scenePos.y() < titleBarHeight) {
-        scenePos.setY(titleBarHeight);
-    } else {
-        qreal maxh = scene()->sceneRect().height() - titleBarHeight;
-        if (scenePos.y() > maxh)
-            scenePos.setY(maxh);
+    // fallback: square at right end of titlebar (Windows/Linux style)
+    return QRectF(frameRectF.right() - kTitleBarHeight, frameRectF.top(), kTitleBarHeight, kTitleBarHeight);
+}
+
+QGraphicsView *ZoneViewWidget::findDragView(QWidget *eventWidget) const
+{
+    QWidget *current = eventWidget;
+    while (current) {
+        if (auto *view = qobject_cast<QGraphicsView *>(current))
+            return view;
+        current = current->parentWidget();
     }
 
-    if (scenePos != pos())
-        setPos(scenePos);
+    if (scene() && !scene()->views().isEmpty())
+        return scene()->views().constFirst();
+
+    return nullptr;
+}
+
+QPointF ZoneViewWidget::calcDraggedWindowPos(const QPoint &screenPos,
+                                             const QPointF &scenePos,
+                                             const QPointF &buttonDownScenePos) const
+{
+    if (dragView && dragView->viewport()) {
+        const QPoint vpStart = dragView->viewport()->mapFromGlobal(dragStartScreenPos);
+        const QPoint vpNow = dragView->viewport()->mapFromGlobal(screenPos);
+        const QPointF sceneStart = dragView->mapToScene(vpStart);
+        const QPointF sceneNow = dragView->mapToScene(vpNow);
+        return dragStartItemPos + (sceneNow - sceneStart);
+    }
+
+    return dragStartItemPos + (scenePos - buttonDownScenePos);
+}
+
+bool ZoneViewWidget::windowFrameEvent(QEvent *event)
+{
+    if (event->type() == QEvent::UngrabMouse) {
+        stopWindowDrag();
+        return QGraphicsWidget::windowFrameEvent(event);
+    }
+
+    auto *me = dynamic_cast<QGraphicsSceneMouseEvent *>(event);
+    if (!me)
+        return QGraphicsWidget::windowFrameEvent(event);
+
+    switch (event->type()) {
+        case QEvent::GraphicsSceneMousePress:
+            if (me->button() == Qt::LeftButton && windowFrameSectionAt(me->pos()) == Qt::TitleBarArea) {
+                // avoid drag on close button
+                if (closeButtonRect(me->widget()).contains(me->pos())) {
+                    me->accept();
+                    close();
+                    return true;
+                }
+                startWindowDrag(me);
+                me->accept();
+                return true;
+            }
+            break;
+
+        case QEvent::GraphicsSceneMouseMove:
+            if (draggingWindow) {
+                if (!(me->buttons() & Qt::LeftButton)) {
+                    stopWindowDrag();
+                } else {
+                    setPos(
+                        calcDraggedWindowPos(me->screenPos(), me->scenePos(), me->buttonDownScenePos(Qt::LeftButton)));
+                }
+                me->accept();
+                return true;
+            }
+            break;
+
+        case QEvent::GraphicsSceneMouseRelease:
+            if (draggingWindow && me->button() == Qt::LeftButton) {
+                stopWindowDrag();
+                me->accept();
+                return true;
+            }
+            break;
+
+        default:
+            break;
+    }
+
+    return QGraphicsWidget::windowFrameEvent(event);
+}
+
+void ZoneViewWidget::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
+{
+    // move if the scene routes moves while dragging
+    if (draggingWindow && (event->buttons() & Qt::LeftButton)) {
+        setPos(calcDraggedWindowPos(event->screenPos(), event->scenePos(), event->buttonDownScenePos(Qt::LeftButton)));
+        event->accept();
+        return;
+    }
+
+    QGraphicsWidget::mouseMoveEvent(event);
+}
+
+void ZoneViewWidget::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
+{
+    if (draggingWindow && event->button() == Qt::LeftButton) {
+        stopWindowDrag();
+        event->accept();
+        return;
+    }
+
+    QGraphicsWidget::mouseReleaseEvent(event);
+}
+
+QVariant ZoneViewWidget::itemChange(GraphicsItemChange change, const QVariant &value)
+{
+    if (change == QGraphicsItem::ItemPositionChange && scene()) {
+        // Keep grab area in main view
+        const QRectF sceneRect = scene()->sceneRect();
+        const QPointF requestedPos = value.toPointF();
+        QPointF desiredPos = requestedPos;
+
+        const qreal minX = sceneRect.left();
+        const qreal maxX = qMax(minX, sceneRect.right() - kMinVisibleWidth);
+        const qreal minY = sceneRect.top() + kTitleBarHeight;
+        const qreal maxY = qMax(minY, sceneRect.bottom() - kTitleBarHeight);
+
+        desiredPos.setX(qBound(minX, desiredPos.x(), maxX));
+        desiredPos.setY(qBound(minY, desiredPos.y(), maxY));
+        return desiredPos;
+    }
+
+    return QGraphicsWidget::itemChange(change, value);
 }
 
 void ZoneViewWidget::resizeEvent(QGraphicsSceneResizeEvent *event)
@@ -350,6 +507,7 @@ void ZoneViewWidget::handleScrollBarChange(int value)
 
 void ZoneViewWidget::closeEvent(QCloseEvent *event)
 {
+    stopWindowDrag();
     disconnect(zone, &ZoneViewZone::closed, this, 0);
     // manually call zone->close in order to remove it from the origZones views
     zone->close();

cockatrice/src/game/zones/view_zone_widget.h

@@ -3,7 +3,6 @@
  * @ingroup GameGraphicsZones
  * @brief TODO: Document this.
  */
-
 #ifndef ZONEVIEWWIDGET_H
 #define ZONEVIEWWIDGET_H
 
@@ -14,6 +13,7 @@
 #include <QGraphicsProxyWidget>
 #include <QGraphicsWidget>
 #include <QLineEdit>
+#include <QPointer>
 #include <libcockatrice/utility/macros.h>
 
 class QLabel;
@@ -28,6 +28,8 @@ class ServerInfo_Card;
 class QGraphicsSceneMouseEvent;
 class QGraphicsSceneWheelEvent;
 class QStyleOption;
+class QGraphicsView;
+class QWidget;
 
 class ScrollableGraphicsProxyWidget : public QGraphicsProxyWidget
 {
@@ -66,6 +68,33 @@ private:
     int extraHeight;
     Player *player;
 
+    bool draggingWindow = false;
+    QPoint dragStartScreenPos;
+    QPointF dragStartItemPos;
+    QPointer<QGraphicsView> dragView;
+
+    void stopWindowDrag();
+    void startWindowDrag(QGraphicsSceneMouseEvent *event);
+    QRectF closeButtonRect(QWidget *styleWidget) const;
+    /**
+     * @brief Resolves the QGraphicsView to use for drag coordinate mapping
+     *
+     * @param eventWidget QWidget that originated the mouse event
+     * @return The resolved QGraphicsView
+     */
+    QGraphicsView *findDragView(QWidget *eventWidget) const;
+    /**
+     * @brief Calculates the desired widget position while dragging
+     *
+     * @param screenPos Global screen coordinates of the current mouse position
+     * @param scenePos Scene coordinates of the current mouse position
+     * @param buttonDownScenePos Scene coordinates of the initial mouse press position
+     *
+     * @return The new widget position in scene coordinates
+     */
+    QPointF
+    calcDraggedWindowPos(const QPoint &screenPos, const QPointF &scenePos, const QPointF &buttonDownScenePos) const;
+
     void resizeScrollbar(qreal newZoneHeight);
 signals:
     void closePressed(ZoneViewWidget *zv);
@@ -76,7 +105,6 @@ private slots:
     void resizeToZoneContents(bool forceInitialHeight = false);
     void handleScrollBarChange(int value);
     void zoneDeleted();
-    void moveEvent(QGraphicsSceneMoveEvent * /* event */) override;
     void resizeEvent(QGraphicsSceneResizeEvent * /* event */) override;
     void expandWindow();
 
@@ -101,6 +129,10 @@ public:
 protected:
     void closeEvent(QCloseEvent *event) override;
     void initStyleOption(QStyleOption *option) const override;
+    bool windowFrameEvent(QEvent *event) override;
+    QVariant itemChange(GraphicsItemChange change, const QVariant &value) override;
+    void mouseMoveEvent(QGraphicsSceneMouseEvent *event) override;
+    void mouseReleaseEvent(QGraphicsSceneMouseEvent *event) override;
     void mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event) override;
 };