Source/WebCore/rendering/GridMasonryLayout.h

/*
 * Copyright (C) 2022 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#pragma once

#include "GridArea.h"
#include "GridTrackSizingAlgorithm.h"
#include "LayoutUnit.h"
#include "RenderBox.h"
#include <wtf/CheckedRef.h>
#include <wtf/WeakPtr.h>

namespace WebCore {

namespace Style {
enum class GridTrackSizingDirection : bool;
}

class RenderGrid;

class GridMasonryLayout {
public:
    GridMasonryLayout(RenderGrid& renderGrid)
        : m_renderGrid(renderGrid)
    {
    }

    enum class MasonryLayoutPhase : uint8_t {
        LayoutPhase,
        MinContentPhase,
        MaxContentPhase
    };

    void initializeMasonry(unsigned gridAxisTracks, Style::GridTrackSizingDirection masonryAxisDirection);
    void performMasonryPlacement(const GridTrackSizingAlgorithm&, unsigned gridAxisTracks, Style::GridTrackSizingDirection masonryAxisDirection, GridMasonryLayout::MasonryLayoutPhase);
    LayoutUnit offsetForGridItem(const RenderBox&) const;
    LayoutUnit gridContentSize() const { return m_gridContentSize; };
    LayoutUnit gridGap() const { return m_masonryAxisGridGap; };

private:
    GridArea gridAreaForIndefiniteGridAxisItem(const RenderBox& item);
    GridArea gridAreaForDefiniteGridAxisItem(const RenderBox&) const;

    void placeMasonryItems(const GridTrackSizingAlgorithm&, GridMasonryLayout::MasonryLayoutPhase);
    void setItemGridAxisContainingBlockToGridArea(const GridTrackSizingAlgorithm&, RenderBox&);
    void insertIntoGridAndLayoutItem(const GridTrackSizingAlgorithm&, RenderBox&, const GridArea&, GridMasonryLayout::MasonryLayoutPhase);
    LayoutUnit calculateMasonryIntrinsicLogicalWidth(RenderBox&, GridMasonryLayout::MasonryLayoutPhase);

    void resizeAndResetRunningPositions();
    LayoutUnit masonryAxisMarginBoxForItem(const RenderBox& gridItem);
    void updateRunningPositions(const RenderBox& gridItem, const GridArea&);
    void updateItemOffset(const RenderBox& gridItem, LayoutUnit offset);
    inline Style::GridTrackSizingDirection gridAxisDirection() const;

    bool hasDefiniteGridAxisPosition(const RenderBox& gridItem, Style::GridTrackSizingDirection masonryDirection) const;
    GridArea masonryGridAreaFromGridAxisSpan(const GridSpan&) const;
    GridSpan gridAxisSpanFromArea(const GridArea&) const;
    bool hasEnoughSpaceAtPosition(unsigned startingPosition, unsigned spanLength) const;

    unsigned m_gridAxisTracksCount;

    Vector<LayoutUnit> m_runningPositions;
    HashMap<SingleThreadWeakRef<const RenderBox>, LayoutUnit> m_itemOffsets;
    const CheckedRef<RenderGrid> m_renderGrid;
    LayoutUnit m_masonryAxisGridGap;
    LayoutUnit m_gridContentSize;

    Style::GridTrackSizingDirection m_masonryAxisDirection;
    const GridSpan m_masonryAxisSpan = GridSpan::masonryAxisTranslatedDefiniteGridSpan();

    unsigned m_autoFlowNextCursor;
};

} // end namespace WebCore