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++ // Copyright (C) 2021 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
++
++ #include <QtGui/QCursor>
++ #include <QtWidgets/QGraphicsSceneMouseEvent>
++ #include <QtWidgets/QGraphicsSceneHoverEvent>
++ #include <QtWidgets/QGraphicsScene>
++ #include <QtCharts/QLegendMarker>
++ #include <QtCharts/QChart>
++ #include <private/legendlayout_p.h>
++ #include <private/legendmoveresizehandler_p.h>
++
++ QT_BEGIN_NAMESPACE
++
++ LegendMoveResizeHandler::LegendMoveResizeHandler(QLegend *legend) :
++ m_legend(legend)
++ {
++ m_legend->setAcceptHoverEvents(true);
++ m_legend->setCursor(Qt::ArrowCursor);
++ }
++
++ LegendMoveResizeHandler::~LegendMoveResizeHandler()
++ {
++ }
++
++ void LegendMoveResizeHandler::reset()
++ {
++ m_action = Action::Idle;
++ setMouseCursor(MousePosition::Nowhere);
++ }
++
++ void LegendMoveResizeHandler::handleMousePressEvent(QGraphicsSceneMouseEvent *event)
++ {
++ determineMousePosition(event->pos());
++ m_moveOffset = event->pos();
++ m_action = Action::Pressed;
++
++ // Since the legend does not have a proper frame,
++ // with a title bar, we have replaced the "top" from
++ // being a resize bar to being a move area. This
++ // is evident to the user as the mouse cursor
++ // changes to an open hand while over the top
++ // in hover mode, and a closed hand when the mouse
++ // button is pressed.
++ if (m_legend->isAttachedToChart()) {
++ m_action = Action::Idle;
++ } else if (m_mode == MousePosition::Top) {
++ m_action = Action::Moving;
++ setMouseCursor();
++ } else if (m_mode != MousePosition::Nowhere) {
++ m_action = Action::Resizing;
++ }
++ }
++
++ void LegendMoveResizeHandler::handleMouseMoveEvent(QGraphicsSceneMouseEvent *event)
++ {
++ QRectF geom = m_legend->geometry();
++ QMarginsF reattachMargins{m_reattachThreshold, m_reattachThreshold, m_reattachThreshold, m_reattachThreshold};
++ QRectF dragArea = m_legend->parentWidget()->geometry() - reattachMargins;
++
++ if (m_action == Action::Moving) {
++ bool reattach = true;
++ QPointF toPoint = event->scenePos() - m_moveOffset;
++
++ if (event->scenePos().x() <= dragArea.left())
++ m_legend->setAlignment(Qt::AlignLeft);
++ else if (event->scenePos().x() >= dragArea.right())
++ m_legend->setAlignment(Qt::AlignRight);
++ else if (event->scenePos().y() <= dragArea.top())
++ m_legend->setAlignment(Qt::AlignTop);
++ else if (event->scenePos().y() >= dragArea.bottom())
++ m_legend->setAlignment(Qt::AlignBottom);
++ else
++ reattach = false;
++
++ QRectF potentialGeom(geom);
++ potentialGeom.moveTopLeft(toPoint);
++ if (potentialGeom.left() <= dragArea.left())
++ toPoint.setX(dragArea.left());
++ else if (potentialGeom.right() >= dragArea.right())
++ toPoint.setX(dragArea.right() - geom.width());
++
++ if (potentialGeom.top() <= dragArea.top())
++ toPoint.setY(dragArea.top());
++ else if (potentialGeom.bottom() >= dragArea.bottom())
++ toPoint.setY(dragArea.bottom() - geom.height());
++
++ // Set the geometry to be the new desired position corrected to
++ // be within the bounds of the dragArea.
++ geom.moveTopLeft(toPoint);
++ if (geom != m_legend->geometry())
++ m_legend->setGeometry(geom);
++
++ if (reattach && !m_legend->isAttachedToChart()) {
++ m_action = Action::Idle;
++ m_mode = MousePosition::Nowhere;
++ setMouseCursor();
++ m_legend->attachToChart();
++ }
++ } else if (m_action == Action::Resizing) {
++ QPointF trackPoint = event->scenePos();
++ QRectF boundRect = m_legend->parentWidget()->geometry();
++
++ if (trackPoint.x() <= boundRect.left())
++ trackPoint.rx() = boundRect.left() + 1;
++ else if (trackPoint.x() >= boundRect.right())
++ trackPoint.rx() = boundRect.right() - 1;
++
++ if (trackPoint.y() <= boundRect.top())
++ trackPoint.ry() = boundRect.top() + 1;
++ else if (trackPoint.y() >= boundRect.bottom())
++ trackPoint.ry() = boundRect.bottom();
++
++ switch (m_mode) {
++ case MousePosition::TopLeft:
++ geom = QRectF(trackPoint, geom.bottomRight());
++ break;
++ case MousePosition::BottomRight:
++ geom = QRectF(geom.topLeft(), trackPoint);
++ break;
++ case MousePosition::BottomLeft:
++ geom = QRectF(QPointF(trackPoint.x(), geom.y()), QPointF(geom.right(), trackPoint.y()));
++ break;
++ case MousePosition::TopRight:
++ geom = QRectF(QPointF(geom.x(), trackPoint.y()), QPoint(trackPoint.x(), geom.bottom()));
++ break;
++ case MousePosition::Bottom:
++ geom = QRectF(geom.topLeft(), QPointF(geom.right(), trackPoint.y()));
++ break;
++ case MousePosition::Left:
++ geom = QRectF(QPointF(trackPoint.x(), geom.top()), geom.bottomRight());
++ break;
++ case MousePosition::Right:
++ geom = QRectF(geom.topLeft(), QPointF(trackPoint.x(), geom.bottom()));
++ break;
++ default:
++ break;
++ }
++
++ geom = QRectF(geom.topLeft(),
++ geom.size().expandedTo(m_legend->d_ptr->m_layout->minimumSize())
++ .boundedTo((boundRect & geom).size()));
++
++ if (geom.size() != m_legend->geometry().size())
++ m_legend->setGeometry(geom);
++ }
++ }
++
++ void LegendMoveResizeHandler::handleMouseReleaseEvent(QGraphicsSceneMouseEvent *event)
++ {
++ m_action = Action::Idle;
++ determineMousePosition(event->pos());
++ setMouseCursor();
++ }
++
++ void LegendMoveResizeHandler::handleHoverEnterEvent(QGraphicsSceneHoverEvent *event)
++ {
++ if (!m_legend->isAttachedToChart()) {
++ determineMousePosition(event->pos());
++ setMouseCursor();
++ }
++ m_action = Action::Hovered;
++ }
++
++ void LegendMoveResizeHandler::handleHoverMoveEvent(QGraphicsSceneHoverEvent *event)
++ {
++ if (!m_legend->isAttachedToChart()) {
++ determineMousePosition(event->pos());
++ setMouseCursor();
++ }
++ m_action = Action::Hovered;
++ }
++
++ void LegendMoveResizeHandler::handleHoverLeaveEvent(QGraphicsSceneHoverEvent *)
++ {
++ if (!m_legend->isAttachedToChart()) {
++ m_mode = MousePosition::Nowhere;
++ setMouseCursor();
++ }
++ m_action = Action::Idle;
++ }
++
++ void LegendMoveResizeHandler::setMouseCursor()
++ {
++ setMouseCursor(m_mode);
++ }
++
++ void LegendMoveResizeHandler::setMouseCursor(MousePosition mpos)
++ {
++ #ifdef QT_NO_CURSOR
++ Q_UNUSED(mpos);
++ return;
++ #else
++ const QList<QGraphicsItem*> items = m_legend->d_ptr->m_items->childItems();
++ for (const auto item : items) {
++ if (!item->hasCursor())
++ item->setCursor(Qt::ArrowCursor);
++ }
++
++ switch (mpos) {
++ case MousePosition::TopLeft:
++ case MousePosition::BottomRight:
++ m_legend->setCursor(Qt::SizeFDiagCursor);
++ break;
++ case MousePosition::BottomLeft:
++ case MousePosition::TopRight:
++ m_legend->setCursor(Qt::SizeBDiagCursor);
++ break;
++ case MousePosition::Top:
++ if (m_action == Action::Moving)
++ m_legend->setCursor(Qt::ClosedHandCursor);
++ else
++ m_legend->setCursor(Qt::OpenHandCursor);
++ break;
++ case MousePosition::Bottom:
++ m_legend->setCursor(Qt::SizeVerCursor);
++ break;
++ case MousePosition::Left:
++ case MousePosition::Right:
++ m_legend->setCursor(Qt::SizeHorCursor);
++ break;
++ case MousePosition::Nowhere:
++ m_legend->setCursor(Qt::ArrowCursor);
++ break;
++ }
++ #endif
++ }
++
++ void LegendMoveResizeHandler::determineMousePosition(QPointF fromPoint)
++ {
++ QRectF contentRect = m_legend->d_ptr->m_layout->contentsRect();
++
++ if (fromPoint.x() <= contentRect.left()) {
++ if (fromPoint.y() <= contentRect.top())
++ m_mode = MousePosition::TopLeft;
++ else if (fromPoint.y() >= contentRect.bottom())
++ m_mode = MousePosition::BottomLeft;
++ else
++ m_mode = MousePosition::Left;
++ } else if (fromPoint.x() > contentRect.left() && fromPoint.x() < contentRect.right()) {
++ if (fromPoint.y() <= contentRect.top())
++ m_mode = MousePosition::Top;
++ else if (fromPoint.y() >= contentRect.bottom())
++ m_mode = MousePosition::Bottom;
++ else
++ // This catches a corner case where the mouse
++ // position y is inside of the content rect
++ m_mode = MousePosition::Nowhere;
++ } else if (fromPoint.x() >= contentRect.left()) {
++ if (fromPoint.y() <= contentRect.top())
++ m_mode = MousePosition::TopRight;
++ else if (fromPoint.y() >= contentRect.bottom())
++ m_mode = MousePosition::BottomRight;
++ else
++ m_mode = MousePosition::Right;
++ } else {
++ m_mode = MousePosition::Nowhere;
++ }
++ }
++
++ QT_END_NAMESPACE