Source/WebCore/css/CSSToLengthConversionData.h

/*
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#pragma once

#include <WebCore/CSSPrimitiveNumericRange.h>
#include <WebCore/CSSPropertyNames.h>
#include <WebCore/Element.h>
#include <optional>
#include <wtf/Assertions.h>

namespace WebCore {

class Element;
class FloatSize;
class FontCascade;
class RenderStyle;
class RenderView;

namespace Style {
class BuilderState;
};

class CSSToLengthConversionData {
public:
    CSSToLengthConversionData();
    CSSToLengthConversionData(const CSSToLengthConversionData&);
    CSSToLengthConversionData(CSSToLengthConversionData&&);

    // This is used during style building. The 'zoom' property is taken into account.
    CSSToLengthConversionData(const RenderStyle&, Style::BuilderState&);
    // This constructor ignores the `zoom` property.
    CSSToLengthConversionData(const RenderStyle&, const RenderStyle* rootStyle, const RenderStyle* parentStyle, const RenderView*, const Element* elementForContainerUnitResolution = nullptr);

    WEBCORE_EXPORT ~CSSToLengthConversionData();

    const RenderStyle* style() const { return m_style; }
    const RenderStyle* rootStyle() const { return m_rootStyle; }
    const RenderStyle* parentStyle() const { return m_parentStyle; }
    float zoom() const;
    CSS::RangeZoomOptions rangeZoomOption() const { return m_rangeZoomOption; }
    bool computingFontSize() const { return m_propertyToCompute == CSSPropertyFontSize; }
    bool computingLineHeight() const { return m_propertyToCompute == CSSPropertyLineHeight; }
    CSSPropertyID propertyToCompute() const { return m_propertyToCompute.value_or(CSSPropertyInvalid); }
    bool evaluationTimeZoomEnabled() const;
    const RenderView* renderView() const { return m_renderView; }
    const Element* elementForContainerUnitResolution() const { return m_elementForContainerUnitResolution.get(); }

    const FontCascade& fontCascadeForFontUnits() const;
    float computedLineHeightForFontUnits() const;

    FloatSize defaultViewportFactor() const;
    FloatSize smallViewportFactor() const;
    FloatSize largeViewportFactor() const;
    FloatSize dynamicViewportFactor() const;

    CSSToLengthConversionData copyForFontSize() const
    {
        CSSToLengthConversionData copy(*this);
        copy.m_zoom = 1.f;
        copy.m_propertyToCompute = CSSPropertyFontSize;
        return copy;
    };

    CSSToLengthConversionData copyWithAdjustedZoom(float zoom, CSS::RangeZoomOptions rangeZoomOption = CSS::RangeZoomOptions::Default) const
    {
        CSSToLengthConversionData copy(*this);
        copy.m_zoom = zoom;
        copy.m_rangeZoomOption = rangeZoomOption;
        return copy;
    }

    CSSToLengthConversionData copyForLineHeight(float zoom) const
    {
        CSSToLengthConversionData copy(*this);
        copy.m_zoom = zoom;
        copy.m_propertyToCompute = CSSPropertyLineHeight;
        copy.m_rangeZoomOption = CSS::RangeZoomOptions::Unzoomed;
        return copy;
    }

    void setUsesContainerUnits() const;

    Style::BuilderState* styleBuilderState() const { return m_styleBuilderState.get(); }
    CheckedPtr<Style::BuilderState> protectedStyleBuilderState() const;

private:
    const RenderStyle* m_style { nullptr };
    const RenderStyle* m_rootStyle { nullptr };
    const RenderStyle* m_parentStyle { nullptr };
    const RenderView* m_renderView { nullptr };
    RefPtr<const Element> m_elementForContainerUnitResolution;
    std::optional<float> m_zoom;
    std::optional<CSSPropertyID> m_propertyToCompute;
    CheckedPtr<Style::BuilderState> m_styleBuilderState;
    CSS::RangeZoomOptions m_rangeZoomOption { CSS::RangeZoomOptions::Default };
};

} // namespace WebCore