Source/WebCore/rendering/RenderGrid.h

/*
 * Copyright (C) 2011 Apple Inc. All rights reserved.
 * Copyright (C) 2013, 2014 Igalia S.L.
 *
 * 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
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#if ENABLE(CSS_GRID_LAYOUT)

#include "GridPositionsResolver.h"
#include "OrderIterator.h"
#include "RenderBlock.h"

namespace WebCore {

class GridArea;
class GridSpan;
class GridTrack;
class GridItemWithSpan;

struct ContentAlignmentData;

enum GridAxisPosition {GridAxisStart, GridAxisEnd, GridAxisCenter};

enum TrackSizeComputationPhase {
    ResolveIntrinsicMinimums,
    ResolveContentBasedMinimums,
    ResolveMaxContentMinimums,
    ResolveIntrinsicMaximums,
    ResolveMaxContentMaximums,
    MaximizeTracks,
};

class RenderGrid final : public RenderBlock {
public:
    RenderGrid(Element&, RenderStyle&&);
    virtual ~RenderGrid();

    Element& element() const { return downcast<Element>(nodeForNonAnonymous()); }

    void styleDidChange(StyleDifference, const RenderStyle* oldStyle) override;
    void layoutBlock(bool relayoutChildren, LayoutUnit pageLogicalHeight = 0) override;

    bool avoidsFloats() const override { return true; }
    bool canDropAnonymousBlockChild() const override { return false; }

    Vector<LayoutUnit> trackSizesForComputedStyle(GridTrackSizingDirection) const;

    const Vector<LayoutUnit>& columnPositions() const { return m_columnPositions; }
    const Vector<LayoutUnit>& rowPositions() const { return m_rowPositions; }

    unsigned autoRepeatCountForDirection(GridTrackSizingDirection direction) const { return m_grid.autoRepeatTracks(direction); }

private:
    const char* renderName() const override;
    bool isRenderGrid() const override { return true; }
    void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const override;

    std::optional<LayoutUnit> computeIntrinsicLogicalContentHeightUsing(Length logicalHeightLength, std::optional<LayoutUnit> intrinsicContentHeight, LayoutUnit borderAndPadding) const override;

    class Grid;
    class GridIterator;
    class GridSizingData;
    enum SizingOperation { TrackSizing, IntrinsicSizeComputation };
    void computeUsedBreadthOfGridTracks(GridTrackSizingDirection, GridSizingData&, LayoutUnit& baseSizesWithoutMaximization, LayoutUnit& growthLimitsWithoutMaximization) const;
    void computeFlexSizedTracksGrowth(GridTrackSizingDirection, SizingOperation, Vector<GridTrack>&, const Vector<unsigned>& flexibleSizedTracksIndex, double flexFraction, Vector<LayoutUnit>& increments, LayoutUnit& totalGrowth) const;
    LayoutUnit computeUsedBreadthOfMinLength(const GridTrackSize&, LayoutUnit maxSize) const;
    LayoutUnit computeUsedBreadthOfMaxLength(const GridTrackSize&, LayoutUnit usedBreadth, LayoutUnit maxSize) const;
    void resolveContentBasedTrackSizingFunctions(GridTrackSizingDirection, GridSizingData&) const;

    unsigned computeAutoRepeatTracksCount(GridTrackSizingDirection, SizingOperation) const;

    typedef ListHashSet<size_t> OrderedTrackIndexSet;
    std::unique_ptr<OrderedTrackIndexSet> computeEmptyTracksForAutoRepeat(Grid&, GridTrackSizingDirection) const;

    void placeItemsOnGrid(Grid&, SizingOperation);
    void populateExplicitGridAndOrderIterator(Grid&) const;
    std::unique_ptr<GridArea> createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(Grid&, const RenderBox&, GridTrackSizingDirection, const GridSpan&) const;
    void placeSpecifiedMajorAxisItemsOnGrid(Grid&, const Vector<RenderBox*>&) const;
    void placeAutoMajorAxisItemsOnGrid(Grid&, const Vector<RenderBox*>&) const;
    typedef std::pair<unsigned, unsigned> AutoPlacementCursor;
    void placeAutoMajorAxisItemOnGrid(Grid&, RenderBox&, AutoPlacementCursor&) const;
    GridTrackSizingDirection autoPlacementMajorAxisDirection() const;
    GridTrackSizingDirection autoPlacementMinorAxisDirection() const;

    bool canPerformSimplifiedLayout() const final;
    void prepareChildForPositionedLayout(RenderBox&);
    void layoutPositionedObject(RenderBox&, bool relayoutChildren, bool fixedPositionObjectsOnly) override;
    void offsetAndBreadthForPositionedChild(const RenderBox&, GridTrackSizingDirection, LayoutUnit& offset, LayoutUnit& breadth);

    void computeIntrinsicLogicalHeight(GridSizingData&);
    LayoutUnit computeTrackBasedLogicalHeight(const GridSizingData&) const;
    void computeTrackSizesForDirection(GridTrackSizingDirection, GridSizingData&, LayoutUnit freeSpace);

    void repeatTracksSizingIfNeeded(GridSizingData&, LayoutUnit availableSpaceForColumns, LayoutUnit availableSpaceForRows);

    void layoutGridItems(GridSizingData&);
    void populateGridPositionsForDirection(GridSizingData&, GridTrackSizingDirection);
    void clearGrid();

    static bool shouldProcessTrackForTrackSizeComputationPhase(TrackSizeComputationPhase, const GridTrackSize&);
    static bool trackShouldGrowBeyondGrowthLimitsForTrackSizeComputationPhase(TrackSizeComputationPhase, const GridTrackSize&);
    static void markAsInfinitelyGrowableForTrackSizeComputationPhase(TrackSizeComputationPhase, GridTrack&);
    static void updateTrackSizeForTrackSizeComputationPhase(TrackSizeComputationPhase, GridTrack&);
    LayoutUnit currentItemSizeForTrackSizeComputationPhase(TrackSizeComputationPhase, RenderBox&, GridTrackSizingDirection, GridSizingData&) const;

    typedef struct GridItemsSpanGroupRange GridItemsSpanGroupRange;
    void resolveContentBasedTrackSizingFunctionsForNonSpanningItems(GridTrackSizingDirection, const GridSpan&, RenderBox& gridItem, GridTrack&, GridSizingData&) const;
    template <TrackSizeComputationPhase> void resolveContentBasedTrackSizingFunctionsForItems(GridTrackSizingDirection, GridSizingData&, const GridItemsSpanGroupRange&) const;
    template <TrackSizeComputationPhase> void distributeSpaceToTracks(Vector<GridTrack*>&, Vector<GridTrack*>* growBeyondGrowthLimitsTracks, LayoutUnit& availableLogicalSpace) const;

    typedef HashSet<unsigned, DefaultHash<unsigned>::Hash, WTF::UnsignedWithZeroKeyHashTraits<unsigned>> TrackIndexSet;
    double computeFlexFactorUnitSize(const Vector<GridTrack>&, GridTrackSizingDirection, SizingOperation, double flexFactorSum, LayoutUnit leftOverSpace, const Vector<unsigned, 8>& flexibleTracksIndexes, std::unique_ptr<TrackIndexSet> tracksToTreatAsInflexible = nullptr) const;
    double findFlexFactorUnitSize(const Vector<GridTrack>&, const GridSpan&, GridTrackSizingDirection, SizingOperation, LayoutUnit spaceToFill) const;

    const GridTrackSize& rawGridTrackSize(GridTrackSizingDirection, unsigned) const;
    GridTrackSize gridTrackSize(GridTrackSizingDirection, unsigned, SizingOperation) const;

    bool updateOverrideContainingBlockContentSizeForChild(RenderBox&, GridTrackSizingDirection, GridSizingData&) const;
    LayoutUnit logicalHeightForChild(RenderBox&) const;
    LayoutUnit minSizeForChild(RenderBox&, GridTrackSizingDirection, GridSizingData&) const;
    LayoutUnit minContentForChild(RenderBox&, GridTrackSizingDirection, GridSizingData&) const;
    LayoutUnit maxContentForChild(RenderBox&, GridTrackSizingDirection, GridSizingData&) const;
    GridAxisPosition columnAxisPositionForChild(const RenderBox&) const;
    GridAxisPosition rowAxisPositionForChild(const RenderBox&) const;
    LayoutUnit columnAxisOffsetForChild(const RenderBox&) const;
    LayoutUnit rowAxisOffsetForChild(const RenderBox&) const;
    ContentAlignmentData computeContentPositionAndDistributionOffset(GridTrackSizingDirection, const LayoutUnit& availableFreeSpace, unsigned numberOfGridTracks) const;
    LayoutPoint findChildLogicalPosition(const RenderBox&) const;
    GridArea cachedGridArea(const RenderBox&) const;
    GridSpan cachedGridSpan(const RenderBox&, GridTrackSizingDirection) const;


    LayoutUnit gridAreaBreadthForChild(const RenderBox& child, GridTrackSizingDirection, const GridSizingData&) const;
    LayoutUnit gridAreaBreadthForChildIncludingAlignmentOffsets(const RenderBox&, GridTrackSizingDirection, const GridSizingData&) const;
    LayoutUnit assumedRowsSizeForOrthogonalChild(const RenderBox&, SizingOperation) const;

    void applyStretchAlignmentToTracksIfNeeded(GridTrackSizingDirection, GridSizingData&);

    void paintChildren(PaintInfo& forSelf, const LayoutPoint& paintOffset, PaintInfo& forChild, bool usePrintRect) override;
    bool needToStretchChildLogicalHeight(const RenderBox&) const;
    LayoutUnit marginLogicalHeightForChild(const RenderBox&) const;
    LayoutUnit computeMarginLogicalSizeForChild(GridTrackSizingDirection, const RenderBox&) const;
    LayoutUnit availableAlignmentSpaceForChildBeforeStretching(LayoutUnit gridAreaBreadthForChild, const RenderBox&) const;
    StyleSelfAlignmentData justifySelfForChild(const RenderBox&) const;
    StyleSelfAlignmentData alignSelfForChild(const RenderBox&) const;
    void applyStretchAlignmentToChildIfNeeded(RenderBox&);
    bool hasAutoSizeInColumnAxis(const RenderBox& child) const { return isHorizontalWritingMode() ? child.style().height().isAuto() : child.style().width().isAuto(); }
    bool hasAutoSizeInRowAxis(const RenderBox& child) const { return isHorizontalWritingMode() ? child.style().width().isAuto() : child.style().height().isAuto(); }
    bool allowedToStretchChildAlongColumnAxis(const RenderBox& child) const { return alignSelfForChild(child).position() == ItemPositionStretch && hasAutoSizeInColumnAxis(child) && !hasAutoMarginsInColumnAxis(child); }
    bool allowedToStretchChildAlongRowAxis(const RenderBox& child) const { return justifySelfForChild(child).position() == ItemPositionStretch && hasAutoSizeInRowAxis(child) && !hasAutoMarginsInRowAxis(child); }
    bool hasAutoMarginsInColumnAxis(const RenderBox&) const;
    bool hasAutoMarginsInRowAxis(const RenderBox&) const;
    void resetAutoMarginsAndLogicalTopInColumnAxis(RenderBox& child);
    void updateAutoMarginsInColumnAxisIfNeeded(RenderBox&);
    void updateAutoMarginsInRowAxisIfNeeded(RenderBox&);

#ifndef NDEBUG
    bool tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection, GridSizingData&);
#endif

    LayoutUnit gridGapForDirection(GridTrackSizingDirection) const;
    LayoutUnit guttersSize(GridTrackSizingDirection, unsigned startLine, unsigned span) const;

    bool spanningItemCrossesFlexibleSizedTracks(const GridSpan&, GridTrackSizingDirection, SizingOperation) const;

    unsigned numTracks(GridTrackSizingDirection, const Grid&) const;

    LayoutUnit translateRTLCoordinate(LayoutUnit) const;

    bool isOrthogonalChild(const RenderBox&) const;
    GridTrackSizingDirection flowAwareDirectionForChild(const RenderBox&, GridTrackSizingDirection) const;

    typedef Vector<RenderBox*, 1> GridCell;
    typedef Vector<Vector<GridCell>> GridAsMatrix;
    class Grid final {
    public:
        Grid(RenderGrid& grid) : m_orderIterator(grid) { }

        unsigned numTracks(GridTrackSizingDirection) const;

        void ensureGridSize(unsigned maximumRowSize, unsigned maximumColumnSize);
        void insert(RenderBox&, const GridArea&);

        // Note that each in flow child of a grid container becomes a grid item. This means that
        // this method will return false for a grid container with only out of flow children.
        bool hasGridItems() const { return !m_gridItemArea.isEmpty(); }

        // FIXME: move this to SizingData once placeItemsOnGrid() takes it as argument.
        bool hasAnyOrthogonalGridItem() const { return m_hasAnyOrthogonalGridItem; }
        void setHasAnyOrthogonalGridItem(bool hasAnyOrthogonalGridItem) { m_hasAnyOrthogonalGridItem = hasAnyOrthogonalGridItem; }

        GridArea gridItemArea(const RenderBox& item) const;
        void setGridItemArea(const RenderBox& item, GridArea);

        GridSpan gridItemSpan(const RenderBox&, GridTrackSizingDirection) const;

        const GridCell& cell(unsigned row, unsigned column) const { return m_grid[row][column]; }

        int smallestTrackStart(GridTrackSizingDirection) const;
        void setSmallestTracksStart(int rowStart, int columnStart);

        unsigned autoRepeatTracks(GridTrackSizingDirection) const;
        void setAutoRepeatTracks(unsigned autoRepeatRows, unsigned autoRepeatColumns);

        void setAutoRepeatEmptyColumns(std::unique_ptr<OrderedTrackIndexSet>);
        void setAutoRepeatEmptyRows(std::unique_ptr<OrderedTrackIndexSet>);

        unsigned autoRepeatEmptyTracksCount(GridTrackSizingDirection) const;
        bool hasAutoRepeatEmptyTracks(GridTrackSizingDirection) const;
        bool isEmptyAutoRepeatTrack(GridTrackSizingDirection, unsigned) const;

        OrderedTrackIndexSet* autoRepeatEmptyTracks(GridTrackSizingDirection) const;

        OrderIterator& orderIterator() { return m_orderIterator; }

        void setNeedsItemsPlacement(bool);
        bool needsItemsPlacement() const { return m_needsItemsPlacement; };

    private:
        friend class GridIterator;

        void clear();

        OrderIterator m_orderIterator;

        int m_smallestColumnStart { 0 };
        int m_smallestRowStart { 0 };

        unsigned m_autoRepeatColumns { 0 };
        unsigned m_autoRepeatRows { 0 };

        bool m_hasAnyOrthogonalGridItem { false };
        bool m_needsItemsPlacement { true };

        GridAsMatrix m_grid;

        HashMap<const RenderBox*, GridArea> m_gridItemArea;
        HashMap<const RenderBox*, size_t> m_gridItemsIndexesMap;

        std::unique_ptr<OrderedTrackIndexSet> m_autoRepeatEmptyColumns;
        std::unique_ptr<OrderedTrackIndexSet> m_autoRepeatEmptyRows;
    };
    Grid m_grid;

    Vector<LayoutUnit> m_columnPositions;
    Vector<LayoutUnit> m_rowPositions;
    LayoutUnit m_offsetBetweenColumns;
    LayoutUnit m_offsetBetweenRows;

    std::optional<LayoutUnit> m_minContentHeight;
    std::optional<LayoutUnit> m_maxContentHeight;
};

} // namespace WebCore

SPECIALIZE_TYPE_TRAITS_RENDER_OBJECT(RenderGrid, isRenderGrid())

#endif // ENABLE(CSS_GRID_LAYOUT)