/*
 * SPDX-FileCopyrightText: 2011 Peter Penz <peter.penz19@gmail.com>
 * SPDX-FileCopyrightText: 2012 Frank Reininghaus <frank78ac@googlemail.com>
 *
 * Based on the Itemviews NG project from Trolltech Labs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "kitemlistcontroller.h"

#include "kitemlistselectionmanager.h"
#include "kitemlistview.h"
#include "private/kitemlistkeyboardsearchmanager.h"
#include "private/kitemlistrubberband.h"
#include "views/draganddrophelper.h"

#include <KTwoFingerSwipe>
#include <KTwoFingerTap>
#include <KUrlMimeData>

#include <QAccessible>
#include <QApplication>
#include <QDrag>
#include <QGesture>
#include <QGraphicsScene>
#include <QGraphicsSceneEvent>
#include <QGraphicsView>
#include <QMimeData>
#include <QTimer>
#include <QTouchEvent>

KItemListController::KItemListController(KItemModelBase *model, KItemListView *view, QObject *parent)
    : QObject(parent)
    , m_singleClickActivationEnforced(false)
    , m_selectionMode(false)
    , m_selectionTogglePressed(false)
    , m_clearSelectionIfItemsAreNotDragged(false)
    , m_isSwipeGesture(false)
    , m_dragActionOrRightClick(false)
    , m_scrollerIsScrolling(false)
    , m_pinchGestureInProgress(false)
    , m_mousePress(false)
    , m_isTouchEvent(false)
    , m_selectionBehavior(NoSelection)
    , m_autoActivationBehavior(ActivationAndExpansion)
    , m_mouseDoubleClickAction(ActivateItemOnly)
    , m_model(nullptr)
    , m_view(nullptr)
    , m_selectionManager(new KItemListSelectionManager(this))
    , m_keyboardManager(new KItemListKeyboardSearchManager(this))
    , m_pressedIndex(std::nullopt)
    , m_pressedMouseGlobalPos()
    , m_autoActivationTimer(nullptr)
    , m_swipeGesture(Qt::CustomGesture)
    , m_twoFingerTapGesture(Qt::CustomGesture)
    , m_oldSelection()
    , m_keyboardAnchorIndex(-1)
    , m_keyboardAnchorPos(0)
{
    connect(m_keyboardManager, &KItemListKeyboardSearchManager::changeCurrentItem, this, &KItemListController::slotChangeCurrentItem, Qt::DirectConnection);
    connect(m_selectionManager, &KItemListSelectionManager::currentChanged, m_keyboardManager, &KItemListKeyboardSearchManager::slotCurrentChanged);
    connect(m_selectionManager, &KItemListSelectionManager::selectionChanged, m_keyboardManager, &KItemListKeyboardSearchManager::slotSelectionChanged);

    m_autoActivationTimer = new QTimer(this);
    m_autoActivationTimer->setSingleShot(true);
    m_autoActivationTimer->setInterval(750);
    connect(m_autoActivationTimer, &QTimer::timeout, this, &KItemListController::slotAutoActivationTimeout);

    setModel(model);
    setView(view);

    m_swipeGesture = QGestureRecognizer::registerRecognizer(new KTwoFingerSwipeRecognizer());
    m_twoFingerTapGesture = QGestureRecognizer::registerRecognizer(new KTwoFingerTapRecognizer());
    view->grabGesture(m_swipeGesture);
    view->grabGesture(m_twoFingerTapGesture);
    view->grabGesture(Qt::TapGesture);
    view->grabGesture(Qt::TapAndHoldGesture);
    view->grabGesture(Qt::PinchGesture);
}

KItemListController::~KItemListController()
{
    setView(nullptr);
    Q_ASSERT(!m_view);

    setModel(nullptr);
    Q_ASSERT(!m_model);
}

void KItemListController::setModel(KItemModelBase *model)
{
    if (m_model == model) {
        return;
    }

    KItemModelBase *oldModel = m_model;
    if (oldModel) {
        oldModel->deleteLater();
    }

    m_model = model;
    if (m_model) {
        m_model->setParent(this);
    }

    if (m_view) {
        m_view->setModel(m_model);
    }

    m_selectionManager->setModel(m_model);

    Q_EMIT modelChanged(m_model, oldModel);
}

KItemModelBase *KItemListController::model() const
{
    return m_model;
}

KItemListSelectionManager *KItemListController::selectionManager() const
{
    return m_selectionManager;
}

void KItemListController::setView(KItemListView *view)
{
    if (m_view == view) {
        return;
    }

    KItemListView *oldView = m_view;
    if (oldView) {
        disconnect(oldView, &KItemListView::scrollOffsetChanged, this, &KItemListController::slotViewScrollOffsetChanged);
        oldView->deleteLater();
    }

    m_view = view;

    if (m_view) {
        m_view->setParent(this);
        m_view->setController(this);
        m_view->setModel(m_model);
        connect(m_view, &KItemListView::scrollOffsetChanged, this, &KItemListController::slotViewScrollOffsetChanged);
        updateExtendedSelectionRegion();
    }

    Q_EMIT viewChanged(m_view, oldView);
}

KItemListView *KItemListController::view() const
{
    return m_view;
}

void KItemListController::setSelectionBehavior(SelectionBehavior behavior)
{
    m_selectionBehavior = behavior;
    updateExtendedSelectionRegion();
}

KItemListController::SelectionBehavior KItemListController::selectionBehavior() const
{
    return m_selectionBehavior;
}

void KItemListController::setAutoActivationBehavior(AutoActivationBehavior behavior)
{
    m_autoActivationBehavior = behavior;
}

KItemListController::AutoActivationBehavior KItemListController::autoActivationBehavior() const
{
    return m_autoActivationBehavior;
}

void KItemListController::setMouseDoubleClickAction(MouseDoubleClickAction action)
{
    m_mouseDoubleClickAction = action;
}

KItemListController::MouseDoubleClickAction KItemListController::mouseDoubleClickAction() const
{
    return m_mouseDoubleClickAction;
}

int KItemListController::indexCloseToMousePressedPosition() const
{
    const QPointF pressedMousePos = m_view->transform().map(m_view->scene()->views().first()->mapFromGlobal(m_pressedMouseGlobalPos.toPoint()));

    QHashIterator<int, KItemListGroupHeader *> it(m_view->m_visibleGroups);
    while (it.hasNext()) {
        it.next();
        KItemListGroupHeader *groupHeader = it.value();
        const QPointF mappedToGroup = groupHeader->mapFromItem(nullptr, pressedMousePos);
        if (groupHeader->contains(mappedToGroup)) {
            return it.key();
        }
    }
    return -1;
}

void KItemListController::setAutoActivationEnabled(bool enabled)
{
    m_autoActivationEnabled = enabled;
}

bool KItemListController::isAutoActivationEnabled() const
{
    return m_autoActivationEnabled;
}

void KItemListController::setSingleClickActivationEnforced(bool singleClick)
{
    m_singleClickActivationEnforced = singleClick;
}

bool KItemListController::singleClickActivationEnforced() const
{
    return m_singleClickActivationEnforced;
}

void KItemListController::setSelectionModeEnabled(bool enabled)
{
    m_selectionMode = enabled;
}

bool KItemListController::selectionMode() const
{
    return m_selectionMode;
}

bool KItemListController::isSearchAsYouTypeActive() const
{
    return m_keyboardManager->isSearchAsYouTypeActive();
}

bool KItemListController::keyPressEvent(QKeyEvent *event)
{
    int index = m_selectionManager->currentItem();
    int key = event->key();
    const bool shiftPressed = event->modifiers() & Qt::ShiftModifier;

    const bool horizontalScrolling = m_view->scrollOrientation() == Qt::Horizontal;

    if (m_view->layoutDirection() == Qt::RightToLeft) {
        // swap left and right arrow keys
        switch (key) {
        case Qt::Key_Left:
            key = Qt::Key_Right;
            break;
        case Qt::Key_Right:
            key = Qt::Key_Left;
            break;
        default:
            break;
        }
    }

    // Handle the expanding/collapsing of items
    // expand / collapse all selected directories
    if (m_view->supportsItemExpanding() && m_model->isExpandable(index) && (key == Qt::Key_Right || key == Qt::Key_Left)) {
        const bool expandOrCollapse = key == Qt::Key_Right ? true : false;
        bool shouldReturn = m_model->setExpanded(index, expandOrCollapse);

        // edit in reverse to preserve index of the first handled items
        const auto selectedItems = m_selectionManager->selectedItems();
        for (auto it = selectedItems.rbegin(); it != selectedItems.rend(); ++it) {
            shouldReturn |= m_model->setExpanded(*it, expandOrCollapse);
            if (!shiftPressed) {
                m_selectionManager->setSelected(*it);
            }
        }
        if (shouldReturn) {
            // update keyboard anchors
            if (shiftPressed) {
                m_keyboardAnchorIndex = selectedItems.count() > 0 ? qMin(index, selectedItems.last()) : index;
                m_keyboardAnchorPos = keyboardAnchorPos(m_keyboardAnchorIndex);
            }

            event->ignore();
            return true;
        }
    }

    const bool controlPressed = event->modifiers() & Qt::ControlModifier;
    if (m_selectionMode && !controlPressed && !shiftPressed && (key == Qt::Key_Enter || key == Qt::Key_Return)) {
        key = Qt::Key_Space; // In selection mode one moves around with arrow keys and toggles selection with Enter.
    }
    const bool navigationPressed = key == Qt::Key_Home || key == Qt::Key_End || key == Qt::Key_PageUp || key == Qt::Key_PageDown || key == Qt::Key_Up
        || key == Qt::Key_Down || key == Qt::Key_Left || key == Qt::Key_Right;

    const int itemCount = m_model->count();

    // For horizontal scroll orientation, transform
    // the arrow keys to simplify the event handling.
    if (horizontalScrolling) {
        switch (key) {
        case Qt::Key_Up:
            key = Qt::Key_Left;
            break;
        case Qt::Key_Down:
            key = Qt::Key_Right;
            break;
        case Qt::Key_Left:
            key = Qt::Key_Up;
            break;
        case Qt::Key_Right:
            key = Qt::Key_Down;
            break;
        default:
            break;
        }
    }

    const bool selectSingleItem = m_selectionBehavior != NoSelection && itemCount == 1 && navigationPressed;

    if (selectSingleItem) {
        const int current = m_selectionManager->currentItem();
        m_selectionManager->setSelected(current);
        return true;
    }

    switch (key) {
    case Qt::Key_Home:
        index = 0;
        m_keyboardAnchorIndex = index;
        m_keyboardAnchorPos = keyboardAnchorPos(index);
        break;

    case Qt::Key_End:
        index = itemCount - 1;
        m_keyboardAnchorIndex = index;
        m_keyboardAnchorPos = keyboardAnchorPos(index);
        break;

    case Qt::Key_Left:
        if (index > 0) {
            const int expandedParentsCount = m_model->expandedParentsCount(index);
            if (expandedParentsCount == 0) {
                --index;
            } else {
                // Go to the parent of the current item.
                do {
                    --index;
                } while (index > 0 && m_model->expandedParentsCount(index) == expandedParentsCount);
            }
            m_keyboardAnchorIndex = index;
            m_keyboardAnchorPos = keyboardAnchorPos(index);
        }
        break;

    case Qt::Key_Right:
        if (index < itemCount - 1) {
            ++index;
            m_keyboardAnchorIndex = index;
            m_keyboardAnchorPos = keyboardAnchorPos(index);
        }
        break;

    case Qt::Key_Up:
        updateKeyboardAnchor();
        if (shiftPressed && !m_selectionManager->isAnchoredSelectionActive() && m_selectionManager->isSelected(index)) {
            m_selectionManager->beginAnchoredSelection(index);
        }
        index = previousRowIndex(index);
        break;

    case Qt::Key_Down:
        updateKeyboardAnchor();
        if (shiftPressed && !m_selectionManager->isAnchoredSelectionActive() && m_selectionManager->isSelected(index)) {
            m_selectionManager->beginAnchoredSelection(index);
        }
        index = nextRowIndex(index);
        break;

    case Qt::Key_PageUp:
        if (horizontalScrolling) {
            // The new current index should correspond to the first item in the current column.
            int newIndex = qMax(index - 1, 0);
            while (newIndex != index && m_view->itemRect(newIndex).topLeft().y() < m_view->itemRect(index).topLeft().y()) {
                index = newIndex;
                newIndex = qMax(index - 1, 0);
            }
            m_keyboardAnchorIndex = index;
            m_keyboardAnchorPos = keyboardAnchorPos(index);
        } else {
            const qreal currentItemBottom = m_view->itemRect(index).bottomLeft().y();
            const qreal height = m_view->geometry().height();

            // The new current item should be the first item in the current
            // column whose itemRect's top coordinate is larger than targetY.
            const qreal targetY = currentItemBottom - height;

            updateKeyboardAnchor();
            int newIndex = previousRowIndex(index);
            do {
                index = newIndex;
                updateKeyboardAnchor();
                newIndex = previousRowIndex(index);
            } while (m_view->itemRect(newIndex).topLeft().y() > targetY && newIndex != index);
        }
        break;

    case Qt::Key_PageDown:
        if (horizontalScrolling) {
            // The new current index should correspond to the last item in the current column.
            int newIndex = qMin(index + 1, m_model->count() - 1);
            while (newIndex != index && m_view->itemRect(newIndex).topLeft().y() > m_view->itemRect(index).topLeft().y()) {
                index = newIndex;
                newIndex = qMin(index + 1, m_model->count() - 1);
            }
            m_keyboardAnchorIndex = index;
            m_keyboardAnchorPos = keyboardAnchorPos(index);
        } else {
            const qreal currentItemTop = m_view->itemRect(index).topLeft().y();
            const qreal height = m_view->geometry().height();

            // The new current item should be the last item in the current
            // column whose itemRect's bottom coordinate is smaller than targetY.
            const qreal targetY = currentItemTop + height;

            updateKeyboardAnchor();
            int newIndex = nextRowIndex(index);
            do {
                index = newIndex;
                updateKeyboardAnchor();
                newIndex = nextRowIndex(index);
            } while (m_view->itemRect(newIndex).bottomLeft().y() < targetY && newIndex != index);
        }
        break;

    case Qt::Key_Enter:
    case Qt::Key_Return: {
        const KItemSet selectedItems = m_selectionManager->selectedItems();
        if (selectedItems.count() >= 2) {
            Q_EMIT itemsActivated(selectedItems);
        } else if (selectedItems.count() == 1) {
            Q_EMIT itemActivated(selectedItems.first());
        } else {
            Q_EMIT itemActivated(index);
        }
        break;
    }

    case Qt::Key_Escape:
        if (m_selectionMode) {
            Q_EMIT selectionModeChangeRequested(false);
        } else if (m_selectionBehavior != SingleSelection) {
            m_selectionManager->clearSelection();
        }
        m_keyboardManager->cancelSearch();
        Q_EMIT escapePressed();
        break;

    case Qt::Key_Space:
        if (m_selectionBehavior == MultiSelection) {
            if (controlPressed || m_selectionMode) {
                // Toggle the selection state of the current item.
                m_selectionManager->endAnchoredSelection();
                m_selectionManager->setSelected(index, 1, KItemListSelectionManager::Toggle);
                m_selectionManager->beginAnchoredSelection(index);
                break;
            } else {
                // Select the current item if it is not selected yet.
                const int current = m_selectionManager->currentItem();
                if (!m_selectionManager->isSelected(current)) {
                    m_selectionManager->setSelected(current);
                    break;
                }
            }
        }
        Q_FALLTHROUGH(); // fall through to the default case and add the Space to the current search string.
    default: {
        // Shift+letter searches backwards. Since the type-ahead search is
        // case-insensitive the capital letter is redundant for matching, so it
        // can be repurposed for backward navigation (bug 374392). Other
        // Shift-produced characters (e.g. punctuation) keep their literal
        // meaning so they remain searchable.
        const QString text = event->text();
        const bool searchBackwards = shiftPressed && text.size() == 1 && text.at(0).isLetter();
        m_keyboardManager->addKeys(text, searchBackwards);
        // Make sure unconsumed events get propagated up the chain. #302329
        event->ignore();
        return false;
    }
    }

    if (m_selectionManager->currentItem() != index) {
        switch (m_selectionBehavior) {
        case NoSelection:
            m_selectionManager->setCurrentItem(index);
            break;

        case SingleSelection:
            m_selectionManager->setCurrentItem(index);
            m_selectionManager->clearSelection();
            m_selectionManager->setSelected(index, 1);
            break;

        case MultiSelection:
            if (controlPressed || (m_selectionMode && !shiftPressed)) {
                m_selectionManager->endAnchoredSelection();
            }

            m_selectionManager->setCurrentItem(index);

            if (!shiftPressed && !controlPressed && !m_selectionMode) {
                m_selectionManager->clearSelection();
                m_selectionManager->setSelected(index, 1);
            }

            if (!shiftPressed) {
                m_selectionManager->beginAnchoredSelection(index);
            }
            break;
        }
    }

    if (navigationPressed) {
        m_view->scrollToItem(index);
    }
    return true;
}

void KItemListController::slotChangeCurrentItem(const QString &text, bool searchFromNextItem, bool searchBackwards, bool *found)
{
    *found = false;
    if (!m_model || m_model->count() == 0) {
        return;
    }
    int index;
    // In selection mode, always use the current (underlined) item, or the adjacent item, as the search start position.
    if (m_selectionBehavior == NoSelection || m_selectionMode || m_selectionManager->hasSelection()) {
        // When advancing to the next match, step away from the current item in
        // the search direction: towards the end when searching forward, towards
        // the beginning when searching backwards.
        int startFromIndex = m_selectionManager->currentItem();
        if (searchFromNextItem) {
            startFromIndex += searchBackwards ? -1 : 1;
        }
        index = m_model->indexForKeyboardSearch(text, startFromIndex, searchBackwards);
    } else {
        index = m_model->indexForKeyboardSearch(text, searchBackwards ? m_model->count() - 1 : 0, searchBackwards);
    }
    if (index >= 0) {
        if (m_selectionMode) {
            m_selectionManager->endAnchoredSelection();
        }

        m_selectionManager->setCurrentItem(index);
        m_keyboardAnchorIndex = index;
        m_keyboardAnchorPos = keyboardAnchorPos(index);

        if (m_selectionBehavior != NoSelection) {
            if (!m_selectionMode) { // Don't clear the selection in selection mode.
                m_selectionManager->replaceSelection(index);
            }
            m_selectionManager->beginAnchoredSelection(index);
        }

        m_view->scrollToItem(index, KItemListView::ViewItemPosition::Beginning);
        *found = true;
    }
    Q_EMIT typeAheadUsed(text, index >= 0 ? std::make_optional<int>(index) : std::nullopt);
}

void KItemListController::slotAutoActivationTimeout()
{
    if (!m_model || !m_view) {
        return;
    }

    const int index = m_autoActivationTimer->property("index").toInt();
    if (index < 0 || index >= m_model->count()) {
        return;
    }

    /* m_view->isUnderMouse() fixes a bug in the Folder-View-Panel and in the
     * Places-Panel.
     *
     * Bug: When you drag a file onto a Folder-View-Item or a Places-Item and
     * then move away before the auto-activation timeout triggers, than the
     * item still becomes activated/expanded.
     *
     * See Bug 293200 and 305783
     */
    if (m_view->isUnderMouse()) {
        if (m_view->supportsItemExpanding() && m_model->isExpandable(index)) {
            const bool expanded = m_model->isExpanded(index);
            m_model->setExpanded(index, !expanded);
        } else if (m_autoActivationBehavior != ExpansionOnly) {
            Q_EMIT itemActivated(index);
        }
    }
}

bool KItemListController::inputMethodEvent(QInputMethodEvent *event)
{
    Q_UNUSED(event)
    return false;
}

bool KItemListController::mousePressEvent(QGraphicsSceneMouseEvent *event, const QTransform &transform)
{
    m_mousePress = true;
    m_pressedMouseGlobalPos = event->screenPos();

    if (event->source() == Qt::MouseEventSynthesizedByQt && m_isTouchEvent) {
        return false;
    }

    if (!m_view) {
        return false;
    }

    const QPointF pressedMousePos = transform.map(event->pos());
    m_pressedIndex = m_view->itemAt(pressedMousePos);

    const Qt::MouseButtons buttons = event->buttons();

    if (!m_pressedIndex.has_value()) {
        Q_EMIT clickViewBackground(event->button());
    }
    
    if (!onPress(event->pos(), event->modifiers(), buttons)) {
        startRubberBand();
        return false;
    }

    return true;
}

bool KItemListController::mouseMoveEvent(QGraphicsSceneMouseEvent *event, const QTransform &transform)
{
    if (!m_view) {
        return false;
    }

    if (m_view->m_tapAndHoldIndicator->isActive()) {
        m_view->m_tapAndHoldIndicator->setActive(false);
    }

    if (event->source() == Qt::MouseEventSynthesizedByQt && !m_dragActionOrRightClick && m_isTouchEvent) {
        return false;
    }

    if (m_pressedIndex.has_value() && !m_view->rubberBand()->isActive()) {
        // Check whether a dragging should be started
        if (event->buttons() & Qt::LeftButton) {
            const auto distance = (event->screenPos() - m_pressedMouseGlobalPos).manhattanLength();
            if (distance >= QApplication::startDragDistance()) {
                if (!m_selectionManager->isSelected(m_pressedIndex.value())) {
                    // Always assure that the dragged item gets selected. Usually this is already
                    // done on the mouse-press event, but when using the selection-toggle on a
                    // selected item the dragged item is not selected yet.
                    m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Toggle);
                } else {
                    // A selected item has been clicked to drag all selected items
                    // -> the selection should not be cleared when the mouse button is released.
                    m_clearSelectionIfItemsAreNotDragged = false;
                }
                startDragging();
                m_mousePress = false;
            }
        }
    } else {
        KItemListRubberBand *rubberBand = m_view->rubberBand();
        if (rubberBand->isActive()) {
            QPointF endPos = transform.map(event->pos());

            // Update the current item.
            const std::optional<int> newCurrent = m_view->itemAt(endPos);
            if (newCurrent.has_value()) {
                // It's expected that the new current index is also the new anchor (bug 163451).
                m_selectionManager->endAnchoredSelection();
                m_selectionManager->setCurrentItem(newCurrent.value());
                m_selectionManager->beginAnchoredSelection(newCurrent.value());
                m_keyboardAnchorIndex = newCurrent.value();
                m_keyboardAnchorPos = keyboardAnchorPos(newCurrent.value());
            }

            if (m_view->scrollOrientation() == Qt::Vertical) {
                endPos.ry() += m_view->scrollOffset();
            } else {
                endPos.rx() += m_view->scrollOffset();
            }
            rubberBand->setEndPosition(endPos);
        }
    }

    return false;
}

bool KItemListController::mouseReleaseEvent(QGraphicsSceneMouseEvent *event, const QTransform &transform)
{
    m_mousePress = false;
    m_isTouchEvent = false;

    if (!m_view) {
        return false;
    }

    for (KItemListWidget *widget : m_view->visibleItemListWidgets()) {
        widget->setPressed(false);
    }

    if (m_view->m_tapAndHoldIndicator->isActive()) {
        m_view->m_tapAndHoldIndicator->setActive(false);
    }

    KItemListRubberBand *rubberBand = m_view->rubberBand();
    if (event->source() == Qt::MouseEventSynthesizedByQt && !rubberBand->isActive() && m_isTouchEvent) {
        return false;
    }

    Q_EMIT mouseButtonReleased(m_pressedIndex.value_or(-1), event->buttons());

    return onRelease(transform.map(event->pos()), event->modifiers(), event->button(), false);
}

bool KItemListController::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event, const QTransform &transform)
{
    const QPointF pos = transform.map(event->pos());
    const std::optional<int> index = m_view->itemAt(pos);

    if (event->button() & (Qt::ForwardButton | Qt::BackButton)) {
        // "Forward" and "Back" are reserved for quickly navigating through the
        // history. Double-clicking those buttons should be interpreted as two
        // separate button presses. We arrive here for the second click, which
        // we now react to just as we would for a singular click
        Q_EMIT mouseButtonPressed(index.value_or(-1), event->button());
        return false;
    }

    if (!index.has_value()) {
        Q_EMIT doubleClickViewBackground(event->button());
        return false;
    }

    // Expand item if desired - See Bug 295573
    if (m_mouseDoubleClickAction != ActivateItemOnly) {
        if (m_view && m_model && m_view->supportsItemExpanding() && m_model->isExpandable(index.value_or(-1))) {
            const bool expanded = m_model->isExpanded(index.value());
            m_model->setExpanded(index.value(), !expanded);
        }
    }

    if (event->button() & ~Qt::LeftButton) {
        return false;
    }

    if (m_view->style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick) || m_singleClickActivationEnforced) {
        return false;
    }

    const bool emitItemActivated = index.has_value() && index.value() < m_model->count() && !m_view->isAboveExpansionToggle(index.value(), pos);
    if (emitItemActivated) {
        Q_EMIT itemActivated(index.value());
    }
    return false;
}

bool KItemListController::contextMenuEvent(QContextMenuEvent *event)
{
    if (event->reason() == QContextMenuEvent::Keyboard) {
        // Emit the signal itemContextMenuRequested() if at least one item is selected.
        // Otherwise the signal viewContextMenuRequested() will be emitted.
        const KItemSet selectedItems = m_selectionManager->selectedItems();
        int index = -1;
        if (selectedItems.count() >= 2) {
            const int currentItemIndex = m_selectionManager->currentItem();
            index = selectedItems.contains(currentItemIndex) ? currentItemIndex : selectedItems.first();
        } else if (selectedItems.count() == 1) {
            index = selectedItems.first();
        }

        if (index >= 0) {
            const QRectF contextRect = m_view->itemContextRect(index);
            const QPointF pos(m_view->scene()->views().first()->mapToGlobal(contextRect.bottomRight().toPoint()));
            Q_EMIT itemContextMenuRequested(index, pos);
        } else {
            Q_EMIT viewContextMenuRequested(event->globalPos());
        }
        return true;
    }

    const auto pos = event->pos();
    const auto globalPos = event->globalPos();

    if (m_view->headerBoundaries().contains(pos)) {
        Q_EMIT headerContextMenuRequested(globalPos);
        return true;
    }

    const auto pressedItem = m_view->itemAt(pos);
    // We only open a context menu for the pressed item if it is selected.
    // That's because the same click might have de-selected the item or because the press was only in the row of the item but not on it.
    if (pressedItem && m_selectionManager->selectedItems().contains(pressedItem.value())) {
        // The selection rectangle for an item was clicked
        Q_EMIT itemContextMenuRequested(pressedItem.value(), globalPos);
        return true;
    }

    // Remove any hover highlights so the context menu doesn't look like it applies to a row.
    const auto widgets = m_view->visibleItemListWidgets();
    for (KItemListWidget *widget : widgets) {
        if (widget->isHovered()) {
            widget->setHovered(false);
            Q_EMIT itemUnhovered(widget->index());
        }
    }
    Q_EMIT viewContextMenuRequested(globalPos);
    return true;
}

bool KItemListController::dragEnterEvent(QGraphicsSceneDragDropEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)

    DragAndDropHelper::clearUrlListMatchesUrlCache();

    return false;
}

bool KItemListController::dragLeaveEvent(QGraphicsSceneDragDropEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)

    m_autoActivationTimer->stop();
    m_view->setAutoScroll(false);
    m_view->hideDropIndicator();

    KItemListWidget *widget = hoveredWidget();
    if (widget) {
        widget->setHovered(false);
        Q_EMIT itemUnhovered(widget->index());
    }
    return false;
}

bool KItemListController::dragMoveEvent(QGraphicsSceneDragDropEvent *event, const QTransform &transform)
{
    if (!m_model || !m_view) {
        return false;
    }

    QUrl hoveredDir = m_model->directory();
    KItemListWidget *oldHoveredWidget = hoveredWidget();

    const QPointF pos = transform.map(event->pos());
    KItemListWidget *newHoveredWidget = widgetForDropPos(pos);
    int index = -1;

    if (oldHoveredWidget != newHoveredWidget) {
        m_autoActivationTimer->stop();

        if (oldHoveredWidget) {
            oldHoveredWidget->setHovered(false);
            Q_EMIT itemUnhovered(oldHoveredWidget->index());
        }
    }

    if (newHoveredWidget) {
        bool droppingBetweenItems = false;
        if (m_model->sortRole().isEmpty()) {
            // The model supports inserting items between other items.
            droppingBetweenItems = (m_view->showDropIndicator(pos) >= 0);
        }

        index = newHoveredWidget->index();

        if (m_model->isDir(index)) {
            hoveredDir = m_model->url(index);
        }

        if (!droppingBetweenItems) {
            // Something has been dragged on an item.
            m_view->hideDropIndicator();
            if (!newHoveredWidget->isHovered()) {
                newHoveredWidget->setHovered(true);
                Q_EMIT itemHovered(index);
            }

            if (m_autoActivationEnabled && !m_autoActivationTimer->isActive() && m_model->canEnterOnHover(index)) {
                m_autoActivationTimer->setProperty("index", index);
                m_autoActivationTimer->start();
                newHoveredWidget->startActivateSoonAnimation(m_autoActivationTimer->remainingTime());
            }

        } else {
            m_autoActivationTimer->stop();
            if (newHoveredWidget->isHovered()) {
                newHoveredWidget->setHovered(false);
                Q_EMIT itemUnhovered(index);
            }
        }
    } else {
        m_view->hideDropIndicator();
    }

    if (DragAndDropHelper::urlListMatchesUrl(event->mimeData()->urls(), hoveredDir)) {
        event->setDropAction(Qt::IgnoreAction);
        event->ignore();
    } else {
        if (m_model->supportsDropping(index)) {
            event->setDropAction(event->proposedAction());
            event->accept();
        } else {
            event->setDropAction(Qt::IgnoreAction);
            event->ignore();
        }
    }
    return false;
}

bool KItemListController::dropEvent(QGraphicsSceneDragDropEvent *event, const QTransform &transform)
{
    if (!m_view) {
        return false;
    }

    m_autoActivationTimer->stop();
    m_view->setAutoScroll(false);

    const QPointF pos = transform.map(event->pos());

    int dropAboveIndex = -1;
    if (m_model->sortRole().isEmpty()) {
        // The model supports inserting of items between other items.
        dropAboveIndex = m_view->showDropIndicator(pos);
    }

    if (dropAboveIndex >= 0) {
        // Something has been dropped between two items.
        m_view->hideDropIndicator();
        Q_EMIT aboveItemDropEvent(dropAboveIndex, event);
    } else if (!event->mimeData()->hasFormat(m_model->blacklistItemDropEventMimeType())) {
        // Something has been dropped on an item or on an empty part of the view.
        const KItemListWidget *receivingWidget = widgetForDropPos(pos);
        if (receivingWidget) {
            Q_EMIT itemDropEvent(receivingWidget->index(), event);
        } else {
            Q_EMIT itemDropEvent(-1, event);
        }
    }

    QAccessibleEvent accessibilityEvent(view(), QAccessible::DragDropEnd);
    QAccessible::updateAccessibility(&accessibilityEvent);

    return true;
}

bool KItemListController::hoverEnterEvent(QGraphicsSceneHoverEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)
    return false;
}

bool KItemListController::hoverMoveEvent(QGraphicsSceneHoverEvent *event, const QTransform &transform)
{
    Q_UNUSED(transform)
    if (!m_model || !m_view) {
        return false;
    }

    // We identify the widget whose expansionArea had been hovered before this hoverMoveEvent() triggered.
    // we can't use hoveredWidget() here (it handles the icon+text rect, not the expansion rect)
    // like hoveredWidget(), we find the hovered widget for the expansion rect
    const auto visibleItemListWidgets = m_view->visibleItemListWidgets();
    const auto oldHoveredExpansionWidgetIterator = std::find_if(visibleItemListWidgets.begin(), visibleItemListWidgets.end(), [](auto &widget) {
        return widget->expansionAreaHovered();
    });
    const auto oldHoveredExpansionWidget =
        oldHoveredExpansionWidgetIterator == visibleItemListWidgets.end() ? std::nullopt : std::make_optional(*oldHoveredExpansionWidgetIterator);

    const auto unhoverOldHoveredWidget = [&]() {
        if (auto oldHoveredWidget = hoveredWidget(); oldHoveredWidget) {
            // handle the text+icon one
            oldHoveredWidget->setHovered(false);
            Q_EMIT itemUnhovered(oldHoveredWidget->index());
        }
    };

    const auto unhoverOldExpansionWidget = [&]() {
        if (oldHoveredExpansionWidget) {
            // then the expansion toggle
            (*oldHoveredExpansionWidget)->setExpansionAreaHovered(false);
        }
    };

    const QPointF pos = transform.map(event->pos());
    if (KItemListWidget *newHoveredWidget = widgetForPos(pos); newHoveredWidget) {
        // something got hovered, work out which part and set hover for the appropriate widget
        const auto mappedPos = newHoveredWidget->mapFromItem(m_view, pos);
        const bool isOnExpansionToggle = newHoveredWidget->expansionToggleRect().contains(mappedPos);

        if (isOnExpansionToggle) {
            // make sure we unhover the old one first if old!=new
            if (oldHoveredExpansionWidget && *oldHoveredExpansionWidget != newHoveredWidget) {
                (*oldHoveredExpansionWidget)->setExpansionAreaHovered(false);
            }
            // we also unhover any old icon+text hovers, in case the mouse movement from icon+text to expansion toggle is too fast (i.e. newHoveredWidget is never null between the transition)
            unhoverOldHoveredWidget();

            newHoveredWidget->setExpansionAreaHovered(true);
        } else {
            // make sure we unhover the old one first if old!=new
            auto oldHoveredWidget = hoveredWidget();
            if (oldHoveredWidget && oldHoveredWidget != newHoveredWidget) {
                oldHoveredWidget->setHovered(false);
                Q_EMIT itemUnhovered(oldHoveredWidget->index());
            }
            // we also unhover any old expansion toggle hovers, in case the mouse movement from expansion toggle to icon+text is too fast (i.e. newHoveredWidget is never null between the transition)
            unhoverOldExpansionWidget();

            const bool isOverIconAndText = newHoveredWidget->selectionRectCore().contains(mappedPos);
            const bool hasMultipleSelection = m_selectionManager->selectedItems().count() > 1;

            if (hasMultipleSelection && !isOverIconAndText) {
                // In case we have multiple selections, clicking on any row will deselect the selection.
                // So, as a visual cue for signalling that clicking anywhere won't select, but clear current highlights,
                // we disable hover of the *row*(i.e. blank space to the right of the icon+text)

                // (no-op in this branch for masked hover)
            } else {
                newHoveredWidget->setHoverPosition(mappedPos);
                if (oldHoveredWidget != newHoveredWidget) {
                    newHoveredWidget->setHovered(true);
                    Q_EMIT itemHovered(newHoveredWidget->index());
                }
            }
        }
    } else {
        // unhover any currently hovered expansion and text+icon widgets
        unhoverOldHoveredWidget();
        unhoverOldExpansionWidget();
    }
    return false;
}

bool KItemListController::hoverLeaveEvent(QGraphicsSceneHoverEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)

    m_mousePress = false;
    m_isTouchEvent = false;

    if (!m_model || !m_view) {
        return false;
    }

    const auto widgets = m_view->visibleItemListWidgets();
    for (KItemListWidget *widget : widgets) {
        widget->setPressed(false);
        if (widget->isHovered()) {
            widget->setHovered(false);
            Q_EMIT itemUnhovered(widget->index());
        }
    }
    return false;
}

bool KItemListController::wheelEvent(QGraphicsSceneWheelEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)
    return false;
}

bool KItemListController::resizeEvent(QGraphicsSceneResizeEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)
    return false;
}

bool KItemListController::gestureEvent(QGestureEvent *event, const QTransform &transform)
{
    if (!m_view) {
        return false;
    }

    //you can touch on different views at the same time, but only one QWidget gets a mousePressEvent
    //we use this to get the right QWidget
    //the only exception is a tap gesture with state GestureStarted, we need to reset some variable
    if (!m_mousePress) {
        if (QGesture *tap = event->gesture(Qt::TapGesture)) {
            QTapGesture *tapGesture = static_cast<QTapGesture *>(tap);
            if (tapGesture->state() == Qt::GestureStarted) {
                tapTriggered(tapGesture, transform);
            }
        }
        return false;
    }

    bool accepted = false;

    if (QGesture *tap = event->gesture(Qt::TapGesture)) {
        tapTriggered(static_cast<QTapGesture *>(tap), transform);
        accepted = true;
    }
    if (event->gesture(Qt::TapAndHoldGesture)) {
        tapAndHoldTriggered(event, transform);
        accepted = true;
    }
    if (event->gesture(Qt::PinchGesture)) {
        pinchTriggered(event, transform);
        accepted = true;
    }
    if (event->gesture(m_swipeGesture)) {
        swipeTriggered(event, transform);
        accepted = true;
    }
    if (event->gesture(m_twoFingerTapGesture)) {
        twoFingerTapTriggered(event, transform);
        accepted = true;
    }
    return accepted;
}

bool KItemListController::touchBeginEvent(QTouchEvent *event, const QTransform &transform)
{
    Q_UNUSED(event)
    Q_UNUSED(transform)

    m_isTouchEvent = true;
    return false;
}

void KItemListController::tapTriggered(QTapGesture *tap, const QTransform &transform)
{
    static bool scrollerWasActive = false;

    if (tap->state() == Qt::GestureStarted) {
        m_dragActionOrRightClick = false;
        m_isSwipeGesture = false;
        m_pinchGestureInProgress = false;
        scrollerWasActive = m_scrollerIsScrolling;
    }

    if (tap->state() == Qt::GestureFinished) {
        m_mousePress = false;

        //if at the moment of the gesture start the QScroller was active, the user made the tap
        //to stop the QScroller and not to tap on an item
        if (scrollerWasActive) {
            return;
        }

        if (m_view->m_tapAndHoldIndicator->isActive()) {
            m_view->m_tapAndHoldIndicator->setActive(false);
        }

        const QPointF pressedMousePos = transform.map(tap->position());
        m_pressedIndex = m_view->itemAt(pressedMousePos);
        if (m_dragActionOrRightClick) {
            m_dragActionOrRightClick = false;
        } else {
            onPress(tap->position().toPoint(), Qt::NoModifier, Qt::LeftButton);
            onRelease(transform.map(tap->position()), Qt::NoModifier, Qt::LeftButton, true);
        }
        m_isTouchEvent = false;
    }
}

void KItemListController::tapAndHoldTriggered(QGestureEvent *event, const QTransform &transform)
{
    //the Qt TabAndHold gesture is triggerable with a mouse click, we don't want this
    if (!m_isTouchEvent) {
        return;
    }

    const QTapAndHoldGesture *tap = static_cast<QTapAndHoldGesture *>(event->gesture(Qt::TapAndHoldGesture));
    if (tap->state() == Qt::GestureFinished) {
        //if a pinch gesture is in progress we don't want a TabAndHold gesture
        if (m_pinchGestureInProgress) {
            return;
        }
        const QPointF pressedMousePos = transform.map(event->mapToGraphicsScene(tap->position()));
        m_pressedIndex = m_view->itemAt(pressedMousePos);
        if (m_pressedIndex.has_value()) {
            if (!m_selectionManager->isSelected(m_pressedIndex.value())) {
                m_selectionManager->clearSelection();
                m_selectionManager->setSelected(m_pressedIndex.value());
            }
            if (!m_selectionMode) {
                Q_EMIT selectionModeChangeRequested(true);
            }
        } else {
            m_selectionManager->clearSelection();
            startRubberBand();
        }

        Q_EMIT scrollerStop();

        m_view->m_tapAndHoldIndicator->setStartPosition(pressedMousePos);
        m_view->m_tapAndHoldIndicator->setActive(true);

        m_dragActionOrRightClick = true;
    }
}

void KItemListController::pinchTriggered(QGestureEvent *event, const QTransform &transform)
{
    Q_UNUSED(transform)

    const QPinchGesture *pinch = static_cast<QPinchGesture *>(event->gesture(Qt::PinchGesture));
    const qreal sensitivityModifier = 0.2;
    static qreal counter = 0;

    if (pinch->state() == Qt::GestureStarted) {
        m_pinchGestureInProgress = true;
        counter = 0;
    }
    if (pinch->state() == Qt::GestureUpdated) {
        //if a swipe gesture was recognized or in progress, we don't want a pinch gesture to change the zoom
        if (m_isSwipeGesture) {
            return;
        }
        counter = counter + (pinch->scaleFactor() - 1);
        if (counter >= sensitivityModifier) {
            Q_EMIT increaseZoom();
            counter = 0;
        } else if (counter <= -sensitivityModifier) {
            Q_EMIT decreaseZoom();
            counter = 0;
        }
    }
}

void KItemListController::swipeTriggered(QGestureEvent *event, const QTransform &transform)
{
    Q_UNUSED(transform)

    const KTwoFingerSwipe *swipe = static_cast<KTwoFingerSwipe *>(event->gesture(m_swipeGesture));

    if (!swipe) {
        return;
    }
    if (swipe->state() == Qt::GestureStarted) {
        m_isSwipeGesture = true;
    }

    if (swipe->state() == Qt::GestureCanceled) {
        m_isSwipeGesture = false;
    }

    if (swipe->state() == Qt::GestureFinished) {
        Q_EMIT scrollerStop();

        if (swipe->swipeAngle() <= 20 || swipe->swipeAngle() >= 340) {
            Q_EMIT mouseButtonPressed(m_pressedIndex.value_or(-1), Qt::BackButton);
        } else if (swipe->swipeAngle() <= 200 && swipe->swipeAngle() >= 160) {
            Q_EMIT mouseButtonPressed(m_pressedIndex.value_or(-1), Qt::ForwardButton);
        } else if (swipe->swipeAngle() <= 110 && swipe->swipeAngle() >= 60) {
            Q_EMIT swipeUp();
        }
        m_isSwipeGesture = true;
    }
}

void KItemListController::twoFingerTapTriggered(QGestureEvent *event, const QTransform &transform)
{
    const KTwoFingerTap *twoTap = static_cast<KTwoFingerTap *>(event->gesture(m_twoFingerTapGesture));

    if (!twoTap) {
        return;
    }

    if (twoTap->state() == Qt::GestureStarted) {
        const QPointF pressedMousePos = transform.map(twoTap->pos());
        m_pressedIndex = m_view->itemAt(pressedMousePos);
        if (m_pressedIndex.has_value()) {
            onPress(twoTap->pos().toPoint(), Qt::ControlModifier, Qt::LeftButton);
            onRelease(transform.map(twoTap->pos()), Qt::ControlModifier, Qt::LeftButton, false);
        }
    }
}

bool KItemListController::processEvent(QEvent *event, const QTransform &transform)
{
    if (!event) {
        return false;
    }

    switch (event->type()) {
    case QEvent::KeyPress:
        return keyPressEvent(static_cast<QKeyEvent *>(event));
    case QEvent::InputMethod:
        return inputMethodEvent(static_cast<QInputMethodEvent *>(event));
    case QEvent::GraphicsSceneMousePress:
        return mousePressEvent(static_cast<QGraphicsSceneMouseEvent *>(event), QTransform());
    case QEvent::GraphicsSceneMouseMove:
        return mouseMoveEvent(static_cast<QGraphicsSceneMouseEvent *>(event), QTransform());
    case QEvent::GraphicsSceneMouseRelease:
        return mouseReleaseEvent(static_cast<QGraphicsSceneMouseEvent *>(event), QTransform());
    case QEvent::GraphicsSceneMouseDoubleClick:
        return mouseDoubleClickEvent(static_cast<QGraphicsSceneMouseEvent *>(event), QTransform());
    case QEvent::ContextMenu:
        return contextMenuEvent(static_cast<QContextMenuEvent *>(event));
    case QEvent::GraphicsSceneWheel:
        return wheelEvent(static_cast<QGraphicsSceneWheelEvent *>(event), QTransform());
    case QEvent::GraphicsSceneDragEnter:
        return dragEnterEvent(static_cast<QGraphicsSceneDragDropEvent *>(event), QTransform());
    case QEvent::GraphicsSceneDragLeave:
        return dragLeaveEvent(static_cast<QGraphicsSceneDragDropEvent *>(event), QTransform());
    case QEvent::GraphicsSceneDragMove:
        return dragMoveEvent(static_cast<QGraphicsSceneDragDropEvent *>(event), QTransform());
    case QEvent::GraphicsSceneDrop:
        return dropEvent(static_cast<QGraphicsSceneDragDropEvent *>(event), QTransform());
    case QEvent::GraphicsSceneHoverEnter:
        return hoverEnterEvent(static_cast<QGraphicsSceneHoverEvent *>(event), QTransform());
    case QEvent::GraphicsSceneHoverMove:
        return hoverMoveEvent(static_cast<QGraphicsSceneHoverEvent *>(event), QTransform());
    case QEvent::GraphicsSceneHoverLeave:
        return hoverLeaveEvent(static_cast<QGraphicsSceneHoverEvent *>(event), QTransform());
    case QEvent::GraphicsSceneResize:
        return resizeEvent(static_cast<QGraphicsSceneResizeEvent *>(event), transform);
    case QEvent::Gesture:
        return gestureEvent(static_cast<QGestureEvent *>(event), transform);
    case QEvent::TouchBegin:
        return touchBeginEvent(static_cast<QTouchEvent *>(event), transform);
    default:
        break;
    }

    return false;
}

void KItemListController::slotViewScrollOffsetChanged(qreal current, qreal previous)
{
    if (!m_view) {
        return;
    }

    KItemListRubberBand *rubberBand = m_view->rubberBand();
    if (rubberBand->isActive()) {
        const qreal diff = current - previous;
        // TODO: Ideally just QCursor::pos() should be used as
        // new end-position but it seems there is no easy way
        // to have something like QWidget::mapFromGlobal() for QGraphicsWidget
        // (... or I just missed an easy way to do the mapping)
        QPointF endPos = rubberBand->endPosition();
        if (m_view->scrollOrientation() == Qt::Vertical) {
            endPos.ry() += diff;
        } else {
            endPos.rx() += diff;
        }

        rubberBand->setEndPosition(endPos);
    }
}

void KItemListController::slotRubberBandChanged()
{
    if (!m_view || !m_model || m_model->count() <= 0) {
        return;
    }

    const KItemListRubberBand *rubberBand = m_view->rubberBand();
    const QPointF startPos = rubberBand->startPosition();
    const QPointF endPos = rubberBand->endPosition();
    QRectF rubberBandRect = QRectF(startPos, endPos).normalized();

    const bool scrollVertical = (m_view->scrollOrientation() == Qt::Vertical);
    if (scrollVertical) {
        rubberBandRect.translate(0, -m_view->scrollOffset());
    } else {
        rubberBandRect.translate(-m_view->scrollOffset(), 0);
    }

    if (!m_oldSelection.isEmpty()) {
        // Clear the old selection that was available before the rubberband has
        // been activated in case if no Shift- or Control-key are pressed
        const bool shiftOrControlPressed = QApplication::keyboardModifiers() & Qt::ShiftModifier || QApplication::keyboardModifiers() & Qt::ControlModifier;
        if (!shiftOrControlPressed && !m_selectionMode) {
            m_oldSelection.clear();
        }
    }

    KItemSet selectedItems;

    // Select all visible items that intersect with the rubberband
    const auto widgets = m_view->visibleItemListWidgets();
    for (const KItemListWidget *widget : widgets) {
        const int index = widget->index();

        const QRectF widgetRect = m_view->itemRect(index);
        if (widgetRect.intersects(rubberBandRect)) {
            // Select the full row intersecting with the rubberband rectangle
            const QRectF selectionRect = widget->selectionRectFull().translated(widgetRect.topLeft());
            if (selectionRect.intersects(rubberBandRect)) {
                selectedItems.insert(index);
            }
        }
    }

    // Select all invisible items that intersect with the rubberband. Instead of
    // iterating all items only the area which might be touched by the rubberband
    // will be checked.
    const bool increaseIndex = scrollVertical ? startPos.y() > endPos.y() : startPos.x() > endPos.x();

    int index = increaseIndex ? m_view->lastVisibleIndex() + 1 : m_view->firstVisibleIndex() - 1;
    bool selectionFinished = false;
    do {
        const QRectF widgetRect = m_view->itemRect(index);
        if (widgetRect.intersects(rubberBandRect)) {
            selectedItems.insert(index);
        }

        if (increaseIndex) {
            ++index;
            selectionFinished = (index >= m_model->count()) || (scrollVertical && widgetRect.top() > rubberBandRect.bottom())
                || (!scrollVertical && widgetRect.left() > rubberBandRect.right());
        } else {
            --index;
            selectionFinished = (index < 0) || (scrollVertical && widgetRect.bottom() < rubberBandRect.top())
                || (!scrollVertical && widgetRect.right() < rubberBandRect.left());
        }
    } while (!selectionFinished);

    if ((QApplication::keyboardModifiers() & Qt::ControlModifier) || m_selectionMode) {
        // If Control is pressed, the selection state of all items in the rubberband is toggled.
        // Therefore, the new selection contains:
        // 1. All previously selected items which are not inside the rubberband, and
        // 2. all items inside the rubberband which have not been selected previously.
        m_selectionManager->setSelectedItems(m_oldSelection ^ selectedItems);
    } else {
        m_selectionManager->setSelectedItems(selectedItems + m_oldSelection);
    }
}

void KItemListController::startDragging()
{
    if (!m_view || !m_model) {
        return;
    }

    const KItemSet selectedItems = m_selectionManager->selectedItems();
    if (selectedItems.isEmpty()) {
        return;
    }

    QMimeData *data = m_model->createMimeData(selectedItems);
    if (!data) {
        return;
    }
    KUrlMimeData::exportUrlsToPortal(data);

    // The created drag object will be owned and deleted
    // by QApplication::activeWindow().
    QDrag *drag = new QDrag(QApplication::activeWindow());
    drag->setMimeData(data);

    const QPixmap pixmap = m_view->createDragPixmap(selectedItems);
    drag->setPixmap(pixmap);

    const QPoint hotSpot((pixmap.width() / pixmap.devicePixelRatio()) / 2, 0);
    drag->setHotSpot(hotSpot);

    drag->exec(Qt::MoveAction | Qt::CopyAction | Qt::LinkAction, Qt::CopyAction);

    QAccessibleEvent accessibilityEvent(view(), QAccessible::DragDropStart);
    QAccessible::updateAccessibility(&accessibilityEvent);
}

KItemListWidget *KItemListController::hoveredWidget() const
{
    Q_ASSERT(m_view);

    const auto widgets = m_view->visibleItemListWidgets();
    for (KItemListWidget *widget : widgets) {
        if (widget->isHovered()) {
            return widget;
        }
    }

    return nullptr;
}

KItemListWidget *KItemListController::widgetForPos(const QPointF &pos) const
{
    Q_ASSERT(m_view);

    if (m_view->headerBoundaries().contains(pos)) {
        return nullptr;
    }

    const auto widgets = m_view->visibleItemListWidgets();
    for (KItemListWidget *widget : widgets) {
        const QPointF mappedPos = widget->mapFromItem(m_view, pos);
        if (widget->contains(mappedPos)) {
            return widget;
        }
    }

    return nullptr;
}

KItemListWidget *KItemListController::widgetForDropPos(const QPointF &pos) const
{
    Q_ASSERT(m_view);

    if (m_view->headerBoundaries().contains(pos)) {
        return nullptr;
    }

    const auto widgets = m_view->visibleItemListWidgets();
    for (KItemListWidget *widget : widgets) {
        const QPointF mappedPos = widget->mapFromItem(m_view, pos);
        if (widget->selectionRectCore().contains(mappedPos)) {
            return widget;
        }
    }

    return nullptr;
}

void KItemListController::updateKeyboardAnchor()
{
    const bool validAnchor =
        m_keyboardAnchorIndex >= 0 && m_keyboardAnchorIndex < m_model->count() && keyboardAnchorPos(m_keyboardAnchorIndex) == m_keyboardAnchorPos;
    if (!validAnchor) {
        const int index = m_selectionManager->currentItem();
        m_keyboardAnchorIndex = index;
        m_keyboardAnchorPos = keyboardAnchorPos(index);
    }
}

int KItemListController::nextRowIndex(int index) const
{
    if (m_keyboardAnchorIndex < 0) {
        return index;
    }

    const int maxIndex = m_model->count() - 1;
    if (index == maxIndex) {
        return index;
    }

    const bool reversed = m_view->layoutDirection() == Qt::RightToLeft && m_view->scrollOrientation() == Qt::Vertical;

    // Calculate the index of the last column inside the row of the current index
    int lastColumnIndex = index;
    while ((!reversed && keyboardAnchorPos(lastColumnIndex + 1) > keyboardAnchorPos(lastColumnIndex))
           || (reversed && keyboardAnchorPos(lastColumnIndex + 1) < keyboardAnchorPos(lastColumnIndex))) {
        ++lastColumnIndex;
        if (lastColumnIndex >= maxIndex) {
            return index;
        }
    }

    // Based on the last column index go to the next row and calculate the nearest index
    // that is below the current index
    int nextRowIndex = lastColumnIndex + 1;
    int searchIndex = nextRowIndex;
    qreal minDiff = qAbs(m_keyboardAnchorPos - keyboardAnchorPos(nextRowIndex));
    while (searchIndex < maxIndex
           && ((!reversed && keyboardAnchorPos(searchIndex + 1) > keyboardAnchorPos(searchIndex))
               || (reversed && keyboardAnchorPos(searchIndex + 1) < keyboardAnchorPos(searchIndex)))) {
        ++searchIndex;
        const qreal searchDiff = qAbs(m_keyboardAnchorPos - keyboardAnchorPos(searchIndex));
        if (searchDiff < minDiff) {
            minDiff = searchDiff;
            nextRowIndex = searchIndex;
        }
    }

    return nextRowIndex;
}

int KItemListController::previousRowIndex(int index) const
{
    if (m_keyboardAnchorIndex < 0 || index == 0) {
        return index;
    }

    const bool reversed = m_view->layoutDirection() == Qt::RightToLeft && m_view->scrollOrientation() == Qt::Vertical;

    // Calculate the index of the first column inside the row of the current index
    int firstColumnIndex = index;
    while ((!reversed && keyboardAnchorPos(firstColumnIndex - 1) < keyboardAnchorPos(firstColumnIndex))
           || (reversed && keyboardAnchorPos(firstColumnIndex - 1) > keyboardAnchorPos(firstColumnIndex))) {
        --firstColumnIndex;
        if (firstColumnIndex <= 0) {
            return index;
        }
    }

    // Based on the first column index go to the previous row and calculate the nearest index
    // that is above the current index
    int previousRowIndex = firstColumnIndex - 1;
    int searchIndex = previousRowIndex;
    qreal minDiff = qAbs(m_keyboardAnchorPos - keyboardAnchorPos(previousRowIndex));
    while (searchIndex > 0
           && ((!reversed && keyboardAnchorPos(searchIndex - 1) < keyboardAnchorPos(searchIndex))
               || (reversed && keyboardAnchorPos(searchIndex - 1) > keyboardAnchorPos(searchIndex)))) {
        --searchIndex;
        const qreal searchDiff = qAbs(m_keyboardAnchorPos - keyboardAnchorPos(searchIndex));
        if (searchDiff < minDiff) {
            minDiff = searchDiff;
            previousRowIndex = searchIndex;
        }
    }

    return previousRowIndex;
}

qreal KItemListController::keyboardAnchorPos(int index) const
{
    const QRectF itemRect = m_view->itemRect(index);
    if (!itemRect.isEmpty()) {
        return (m_view->scrollOrientation() == Qt::Vertical) ? itemRect.x() : itemRect.y();
    }

    return 0;
}

void KItemListController::updateExtendedSelectionRegion()
{
    if (m_view) {
        const bool extend = (m_selectionBehavior != MultiSelection);
        KItemListStyleOption option = m_view->styleOption();
        if (option.extendedSelectionRegion != extend) {
            option.extendedSelectionRegion = extend;
            m_view->setStyleOption(option);
        }
    }
}

bool KItemListController::onPress(const QPointF &pos, const Qt::KeyboardModifiers modifiers, const Qt::MouseButtons buttons)
{
    Q_EMIT mouseButtonPressed(m_pressedIndex.value_or(-1), buttons);

    if (buttons & (Qt::BackButton | Qt::ForwardButton)) {
        // Do not select items when clicking the back/forward buttons, see
        // https://bugs.kde.org/show_bug.cgi?id=327412.
        return true;
    }

    if (buttons & Qt::MiddleButton) {
        // The middle button opens an item in a new tab on release and leaves the selection
        // alone, so there is nothing to select here and no rubber band to draw.
        return true;
    }

    const QPointF pressedMousePos = m_view->transform().map(pos);

    if (m_view->isAboveExpansionToggle(m_pressedIndex.value_or(-1), pressedMousePos)) {
        m_selectionManager->endAnchoredSelection();
        m_selectionManager->setCurrentItem(m_pressedIndex.value());
        m_selectionManager->beginAnchoredSelection(m_pressedIndex.value());
        m_keyboardAnchorIndex = m_pressedIndex.value();
        m_keyboardAnchorPos = keyboardAnchorPos(m_pressedIndex.value());
        return true;
    }

    m_selectionTogglePressed = m_view->isAboveSelectionToggle(m_pressedIndex.value_or(-1), pressedMousePos);
    if (m_selectionTogglePressed) {
        m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Toggle);
        // The previous anchored selection has been finished already in
        // KItemListSelectionManager::setSelected(). We can safely change
        // the current item and start a new anchored selection now.
        m_selectionManager->setCurrentItem(m_pressedIndex.value());
        m_selectionManager->beginAnchoredSelection(m_pressedIndex.value());
        m_keyboardAnchorIndex = m_pressedIndex.value();
        m_keyboardAnchorPos = keyboardAnchorPos(m_pressedIndex.value());
        return true;
    }

    const bool shiftPressed = modifiers & Qt::ShiftModifier;
    const bool controlPressed = (modifiers & Qt::ControlModifier) || m_selectionMode; // Keeping selectionMode similar to pressing control will hopefully
                                                                                      // simplify the overall logic and possibilities both for users and devs.
    const bool leftClick = buttons & Qt::LeftButton;
    const bool rightClick = buttons & Qt::RightButton;
    const bool singleClickActivation = m_view->style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick);

    // The previous selection is cleared if either
    // 1. The selection mode is SingleSelection, or
    // 2. the selection mode is MultiSelection, and *none* of the following conditions are met:
    //    a) Shift or Control are pressed.
    //    b) The clicked item is selected already. In that case, the user might want to:
    //       - start dragging multiple items, or
    //       - open the context menu and perform an action for all selected items.
    const bool shiftOrControlPressed = shiftPressed || controlPressed;
    const bool pressedItemAlreadySelected = m_pressedIndex.has_value() && m_selectionManager->isSelected(m_pressedIndex.value());
    const bool clearSelection = m_selectionBehavior == SingleSelection || (!shiftOrControlPressed && !pressedItemAlreadySelected);

    // When this method returns false, a rubberBand selection is created using KItemListController::startRubberBand via the caller.
    if (clearSelection) {
        const int selectedItemsCount = m_selectionManager->selectedItems().count();
        m_selectionManager->clearSelection();
        // clear and bail when we got an existing multi-selection
        if (selectedItemsCount > 1 && m_pressedIndex.has_value()) {
            const auto row = m_view->m_visibleItems.value(m_pressedIndex.value());
            const auto mappedPos = row->mapFromItem(m_view, pos);
            if (row->selectionRectCore().contains(mappedPos)) {
                // we are indeed inside the text/icon rect, keep m_pressedIndex what it is
                // and short-circuit for single-click activation (it will then propagate to onRelease and activate the item)
                // or we just keep going for double-click activation
                if (singleClickActivation || m_singleClickActivationEnforced) {
                    if (!pressedItemAlreadySelected) {
                        // An unselected item was clicked directly while deselecting multiple other items so we select it.
                        m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Toggle);
                        m_selectionManager->setCurrentItem(m_pressedIndex.value());
                        m_selectionManager->beginAnchoredSelection(m_pressedIndex.value());
                        m_keyboardAnchorIndex = m_pressedIndex.value();
                        m_keyboardAnchorPos = keyboardAnchorPos(m_pressedIndex.value());
                    }
                    if (leftClick) {
                        row->setPressed(true);
                    }
                    return true; // event handled, don't create rubber band
                }
            } else {
                // we're not inside the text/icon rect, as we've already cleared the selection
                // we can just stop here and make sure handlers down the line (i.e. onRelease) don't activate
                m_pressedIndex.reset();
                // we don't stop event propagation and proceed to create a rubber band and let onRelease
                // decide (based on m_pressedIndex) whether we're in a drag (drag => new rubber band, click => don't select the item)
                return false;
            }
        }
    } else if (pressedItemAlreadySelected && !shiftOrControlPressed && leftClick) {
        // The user might want to start dragging multiple items, but if he clicks the item
        // in order to trigger it instead, the other selected items must be deselected.
        // However, we do not know yet what the user is going to do.
        // -> remember that the user pressed an item which had been selected already and
        //    clear the selection in mouseReleaseEvent(), unless the items are dragged.
        m_clearSelectionIfItemsAreNotDragged = true;

        if (m_selectionManager->selectedItems().count() == 1 && m_view->isAboveText(m_pressedIndex.value_or(-1), pressedMousePos)) {
            Q_EMIT selectedItemTextPressed(m_pressedIndex.value_or(-1));
        }
    }

    if (!shiftPressed) {
        // Finish the anchored selection before the current index is changed
        m_selectionManager->endAnchoredSelection();
    }

    if (rightClick) {
        // Stop rubber band from persisting after right-clicks
        KItemListRubberBand *rubberBand = m_view->rubberBand();
        if (rubberBand->isActive()) {
            disconnect(rubberBand, &KItemListRubberBand::endPositionChanged, this, &KItemListController::slotRubberBandChanged);
            rubberBand->setActive(false);
            m_view->setAutoScroll(false);
        }

        if (!m_pressedIndex.has_value()) {
            // We have a right-click in an empty region, don't create rubber band.
            return true;
        }
    }

    if (m_pressedIndex.has_value()) {
        // The hover highlight area of an item is being pressed.
        const auto row = m_view->m_visibleItems.value(m_pressedIndex.value()); // anything outside of row.contains() will be the empty region of the row rect

        const bool hitTargetIsRowEmptyRegion = !row->selectionRectCore().contains(row->mapFromItem(m_view, pos));
        // again, when this method returns false, a rubberBand selection is created as the event is not consumed;
        // createRubberBand here tells us whether to return true or false.
        bool createRubberBand = (hitTargetIsRowEmptyRegion && m_selectionManager->selectedItems().isEmpty());

        if (leftClick) {
            row->setPressed(true);
        }

        if (rightClick && hitTargetIsRowEmptyRegion && !m_view->highlightEntireRow()) {
            // We have a right click outside the icon and text rect but within the hover highlight area.
            // We don't want items to get selected through this, so we return now.
            return true;
        }

        m_selectionManager->setCurrentItem(m_pressedIndex.value());
        m_keyboardAnchorIndex = m_pressedIndex.value();
        m_keyboardAnchorPos = keyboardAnchorPos(m_pressedIndex.value());

        switch (m_selectionBehavior) {
        case NoSelection:
            break;

        case SingleSelection:
            m_selectionManager->setSelected(m_pressedIndex.value());
            Q_FALLTHROUGH();

        case MultiSelection:
            if (controlPressed && !shiftPressed && leftClick) {
                // A left mouse button press is happening on an item while control is pressed. This either means a user wants to:
                // - toggle the selection of item(s) or
                // - they want to begin a drag on the item(s) to copy them.
                // We rule out the latter, if the item is not clicked directly and was unselected previously.
                const auto row = m_view->m_visibleItems.value(m_pressedIndex.value());
                const auto mappedPos = row->mapFromItem(m_view, pos);
                if (!row->selectionRectCore().contains(mappedPos)) {
                    createRubberBand = true;
                } else {
                    m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Toggle);
                    m_selectionManager->beginAnchoredSelection(m_pressedIndex.value());
                    createRubberBand = false; // multi selection, don't propagate any further
                    // This will be the start of an item drag-to-copy operation if the user now moves the mouse before releasing the mouse button.
                }
            } else if (!shiftPressed || !m_selectionManager->isAnchoredSelectionActive()) {
                m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Select);
                m_selectionManager->beginAnchoredSelection(m_pressedIndex.value());
            }
            break;

        default:
            Q_ASSERT(false);
            break;
        }

        return !createRubberBand;
    }

    return false;
}

bool KItemListController::onRelease(const QPointF &pos, const Qt::KeyboardModifiers modifiers, const Qt::MouseButtons buttons, bool touch)
{
    const QPointF pressedMousePos = pos;
    const bool isAboveSelectionToggle = m_view->isAboveSelectionToggle(m_pressedIndex.value_or(-1), pressedMousePos);
    if (isAboveSelectionToggle) {
        m_selectionTogglePressed = false;
        return true;
    }

    if (m_selectionTogglePressed) {
        m_selectionManager->setSelected(m_pressedIndex.value_or(-1), 1, KItemListSelectionManager::Toggle);
        m_selectionTogglePressed = false;
        return true;
    }

    const bool controlPressed = modifiers & Qt::ControlModifier;
    const bool shiftOrControlPressed = modifiers & Qt::ShiftModifier || controlPressed;

    const std::optional<int> index = m_view->itemAt(pos);

    KItemListRubberBand *rubberBand = m_view->rubberBand();
    bool rubberBandRelease = false;
    if (rubberBand->isActive()) {
        disconnect(rubberBand, &KItemListRubberBand::endPositionChanged, this, &KItemListController::slotRubberBandChanged);
        rubberBand->setActive(false);
        m_oldSelection.clear();
        m_view->setAutoScroll(false);
        rubberBandRelease = true;
        // We check for actual rubber band drag here: if delta between start and end is less than drag threshold,
        // then we have a single click on one of the rows
        if ((rubberBand->endPosition() - rubberBand->startPosition()).manhattanLength() < QApplication::startDragDistance()) {
            rubberBandRelease = false; // since we're only selecting, unmark rubber band release flag
            // m_pressedIndex will have no value if we came from a multi-selection clearing onPress
            // in that case, we don't select anything
            if (index.has_value() && m_pressedIndex.has_value()) {
                if (controlPressed && m_selectionBehavior == MultiSelection) {
                    m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Toggle);
                } else {
                    m_selectionManager->setSelected(index.value());
                }
                if (!m_selectionManager->isAnchoredSelectionActive()) {
                    m_selectionManager->beginAnchoredSelection(index.value());
                }
            }
        }
    }

    if (index.has_value() && index == m_pressedIndex) {
        // The release event is done above the same item as the press event

        if (m_clearSelectionIfItemsAreNotDragged) {
            // A selected item has been clicked, but no drag operation has been started
            // -> clear the rest of the selection.
            m_selectionManager->clearSelection();
            m_selectionManager->setSelected(m_pressedIndex.value(), 1, KItemListSelectionManager::Select);
            m_selectionManager->beginAnchoredSelection(m_pressedIndex.value());
        }

        if (buttons & Qt::LeftButton) {
            bool emitItemActivated = true;
            if (m_view->isAboveExpansionToggle(index.value(), pos)) {
                const bool expanded = m_model->isExpanded(index.value());
                m_model->setExpanded(index.value(), !expanded);

                Q_EMIT itemExpansionToggleClicked(index.value());
                emitItemActivated = false;
            } else if (shiftOrControlPressed && m_selectionBehavior != SingleSelection) {
                // The mouse click should only update the selection, not trigger the item, except when
                // we are in single selection mode
                emitItemActivated = false;
            } else {
                const bool singleClickActivation = m_view->style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick) || m_singleClickActivationEnforced;
                if (!singleClickActivation) {
                    emitItemActivated = touch && !m_selectionMode;
                } else {
                    // activate on single click only if we didn't come from a rubber band release
                    emitItemActivated = !rubberBandRelease;
                }
            }
            if (emitItemActivated) {
                Q_EMIT itemActivated(index.value());
            }
        } else if (buttons & Qt::MiddleButton) {
            Q_EMIT itemMiddleClicked(index.value());
        }
    }

    m_pressedMouseGlobalPos = QPointF();
    m_pressedIndex = std::nullopt;
    m_clearSelectionIfItemsAreNotDragged = false;
    return false;
}

void KItemListController::startRubberBand()
{
    if (m_selectionBehavior == MultiSelection) {
        QPoint startPos = m_view->transform().map(m_view->scene()->views().first()->mapFromGlobal(m_pressedMouseGlobalPos.toPoint()));
        if (m_view->scrollOrientation() == Qt::Vertical) {
            startPos.ry() += m_view->scrollOffset();
        } else {
            startPos.rx() += m_view->scrollOffset();
        }

        m_oldSelection = m_selectionManager->selectedItems();
        KItemListRubberBand *rubberBand = m_view->rubberBand();
        rubberBand->setStartPosition(startPos);
        rubberBand->setEndPosition(startPos);
        rubberBand->setActive(true);
        connect(rubberBand, &KItemListRubberBand::endPositionChanged, this, &KItemListController::slotRubberBandChanged);
        m_view->setAutoScroll(true);
    }
}

void KItemListController::slotStateChanged(QScroller::State newState)
{
    if (newState == QScroller::Scrolling) {
        m_scrollerIsScrolling = true;
    } else if (newState == QScroller::Inactive) {
        m_scrollerIsScrolling = false;
    }
}

#include "moc_kitemlistcontroller.cpp"
