Source/WebCore/rendering/FlexibleBoxAlgorithm.h

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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#pragma once

#include "LayoutUnit.h"
#include "RenderStyle.h"
#include <wtf/Forward.h>
#include <wtf/Noncopyable.h>

namespace WebCore {

class RenderBox;

class FlexItem {
public:
    FlexItem(RenderBox&, LayoutUnit flexBaseContentSize, LayoutUnit mainAxisBorderAndPadding, LayoutUnit mainAxisMargin, std::pair<LayoutUnit, LayoutUnit> minMaxSizes, bool everHadLayout);

    LayoutUnit hypotheticalMainAxisMarginBoxSize() const
    {
        return hypotheticalMainContentSize + mainAxisBorderAndPadding + mainAxisMargin;
    }

    LayoutUnit flexBaseMarginBoxSize() const
    {
        return flexBaseContentSize + mainAxisBorderAndPadding + mainAxisMargin;
    }

    LayoutUnit flexedMarginBoxSize() const
    {
        return flexedContentSize + mainAxisBorderAndPadding + mainAxisMargin;
    }

    LayoutUnit constrainSizeByMinMax(const LayoutUnit) const;

    RenderBox& box;
    const LayoutUnit flexBaseContentSize;
    const LayoutUnit mainAxisBorderAndPadding;
    const LayoutUnit mainAxisMargin;
    const std::pair<LayoutUnit, LayoutUnit> minMaxSizes;
    const LayoutUnit hypotheticalMainContentSize;
    LayoutUnit flexedContentSize;
    bool frozen { false };
    bool everHadLayout { false };
};

class FlexLayoutAlgorithm {
    WTF_MAKE_NONCOPYABLE(FlexLayoutAlgorithm);

public:
    FlexLayoutAlgorithm(const RenderStyle&, LayoutUnit lineBreakLength, const Vector<FlexItem>& allItems, LayoutUnit gapBetweenItems, LayoutUnit gapBetweenLines);

    // The hypothetical main size of an item is the flex base size clamped
    // according to its min and max main size properties
    bool computeNextFlexLine(size_t& nextIndex, Vector<FlexItem>& lineItems, LayoutUnit& sumFlexBaseSize, double& totalFlexGrow, double& totalFlexShrink, double& totalWeightedFlexShrink, LayoutUnit& sumHypotheticalMainSize);

private:
    bool isMultiline() const { return m_style.flexWrap() != FlexWrap::NoWrap; }

    const RenderStyle& m_style;
    LayoutUnit m_lineBreakLength;
    const Vector<FlexItem>& m_allItems;

    const LayoutUnit m_gapBetweenItems;
    const LayoutUnit m_gapBetweenLines;
};

} // namespace WebCore