/*
    This file is part of the KDE project
    SPDX-FileCopyrightText: 2007, 2009 Rafael Fernández López <ereslibre@kde.org>

    SPDX-License-Identifier: LGPL-2.0-or-later
*/

#ifndef KCATEGORIZEDVIEW_P_H
#define KCATEGORIZEDVIEW_P_H

#include "kcategorizedview.h"

class KCategorizedSortFilterProxyModel;
class KCategoryDrawer;
class KCategoryDrawerV2;
class KCategoryDrawerV3;

/**
 * @internal
 */
class KCategorizedViewPrivate
{
public:
    struct Block;
    struct Item;

    explicit KCategorizedViewPrivate(KCategorizedView *qq);
    ~KCategorizedViewPrivate();

    /**
     * @return whether this view has all required elements to be categorized.
     */
    bool isCategorized() const;

    /**
     * Wrapper that returns the view's QStyleOptionViewItem, in Qt5 using viewOptions(), and
     * in Qt6 using initViewItemOption().
     */
    QStyleOptionViewItem viewOpts();

    /**
     * @return the block rect for the representative @p representative.
     */
    QStyleOptionViewItem blockRect(const QModelIndex &representative);

    /**
     * Returns the first and last element that intersects with rect.
     *
     * @note see that here we cannot take out items between first and last (as we could
     *       do with the rubberband).
     *
     * Complexity: O(log(n)) where n is model()->rowCount().
     */
    std::pair<QModelIndex, QModelIndex> intersectingIndexesWithRect(const QRect &rect) const;

    /**
     * Returns the position of the block of @p category.
     *
     * Complexity: O(n) where n is the number of different categories when the block has been
     *             marked as in quarantine. O(1) the rest of the times (the vast majority).
     */
    QPoint blockPosition(const QString &category);

    /**
     * Returns the height of the block determined by @p category.
     */
    int blockHeight(const QString &category);

    /**
     * Returns the actual viewport width.
     */
    int viewportWidth() const;

    /**
     * Marks all elements as in quarantine.
     *
     * Complexity: O(n) where n is model()->rowCount().
     *
     * @warning this is an expensive operation
     */
    void regenerateAllElements();

    /**
     * Update internal information, and keep sync with the real information that the model contains.
     */
    void rowsInserted(const QModelIndex &parent, int start, int end);

    /**
     * Returns @p rect in viewport terms, taking in count horizontal and vertical offsets.
     */
    QRect mapToViewport(const QRect &rect) const;

    /**
     * Returns @p rect in absolute terms, converted from viewport position.
     */
    QRect mapFromViewport(const QRect &rect) const;

    /**
     * Returns the height of the highest element in last row. This is only applicable if there is
     * no grid set and uniformItemSizes is false.
     *
     * @param block in which block are we searching. Necessary to stop the search if we hit the
     *              first item in this block.
     */
    int highestElementInLastRow(const Block &block) const;

    /**
     * Returns whether the view has a valid grid size.
     */
    bool hasGrid() const;

    /**
     * Returns the category for the given index.
     */
    QString categoryForIndex(const QModelIndex &index) const;

    /**
     * Updates the visual rect for item when flow is LeftToRight.
     */
    void leftToRightVisualRect(const QModelIndex &index, Item &item, const Block &block, const QPoint &blockPos) const;

    /**
     * Updates the visual rect for item when flow is TopToBottom.
     * @note we only support viewMode == ListMode in this case.
     */
    void topToBottomVisualRect(const QModelIndex &index, Item &item, const Block &block, const QPoint &blockPos) const;

    /**
     * Called when expand or collapse has been clicked on the category drawer.
     */
    void _k_slotCollapseOrExpandClicked(QModelIndex);

    KCategorizedView *const q;
    KCategorizedSortFilterProxyModel *proxyModel = nullptr;
    KCategoryDrawer *categoryDrawer = nullptr;
    int categorySpacing = 0;
    bool alternatingBlockColors = false;
    bool collapsibleBlocks = false;

    Block *const hoveredBlock;
    QString hoveredCategory;
    QModelIndex hoveredIndex;

    QPoint pressedPosition;
    QRect rubberBandRect;

    QHash<QString, Block> blocks;
};

#endif // KCATEGORIZEDVIEW_P_H