Source/WebCore/mathml/MathMLFractionElement.cpp

/*
 * Copyright (C) 2016 Igalia S.L. All rights reserved.
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 * modification, are permitted provided that the following conditions
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#include "config.h"
#include "MathMLFractionElement.h"

#if ENABLE(MATHML)

#include "ElementInlines.h"
#include "RenderMathMLFraction.h"
#include "Settings.h"
#include <wtf/IsoMallocInlines.h>

namespace WebCore {

WTF_MAKE_ISO_ALLOCATED_IMPL(MathMLFractionElement);

using namespace MathMLNames;

inline MathMLFractionElement::MathMLFractionElement(const QualifiedName& tagName, Document& document)
    : MathMLPresentationElement(tagName, document)
{
}

Ref<MathMLFractionElement> MathMLFractionElement::create(const QualifiedName& tagName, Document& document)
{
    return adoptRef(*new MathMLFractionElement(tagName, document));
}

const MathMLElement::Length& MathMLFractionElement::lineThickness()
{
    if (m_lineThickness)
        return m_lineThickness.value();

    auto& thickness = attributeWithoutSynchronization(linethicknessAttr);
    if (document().settings().coreMathMLEnabled()) {
        m_lineThickness = parseMathMLLength(thickness);
        return m_lineThickness.value();
    }

    // The MathML3 recommendation states that "medium" is the default thickness.
    // However, it only states that "thin" and "thick" are respectively thiner and thicker.
    // The MathML in HTML5 implementation note suggests 50% and 200% and these values are also used in Gecko.
    m_lineThickness = Length();
    if (equalLettersIgnoringASCIICase(thickness, "thin")) {
        m_lineThickness.value().type = LengthType::UnitLess;
        m_lineThickness.value().value = .5;
    } else if (equalLettersIgnoringASCIICase(thickness, "medium")) {
        m_lineThickness.value().type = LengthType::UnitLess;
        m_lineThickness.value().value = 1;
    } else if (equalLettersIgnoringASCIICase(thickness, "thick")) {
        m_lineThickness.value().type = LengthType::UnitLess;
        m_lineThickness.value().value = 2;
    } else
        m_lineThickness = parseMathMLLength(thickness);
    return m_lineThickness.value();
}

MathMLFractionElement::FractionAlignment MathMLFractionElement::cachedFractionAlignment(const QualifiedName& name, std::optional<FractionAlignment>& alignment)
{
    if (alignment)
        return alignment.value();

    auto& value = attributeWithoutSynchronization(name);
    if (equalLettersIgnoringASCIICase(value, "left"))
        alignment = FractionAlignmentLeft;
    else if (equalLettersIgnoringASCIICase(value, "right"))
        alignment = FractionAlignmentRight;
    else
        alignment = FractionAlignmentCenter;
    return alignment.value();
}

MathMLFractionElement::FractionAlignment MathMLFractionElement::numeratorAlignment()
{
    return cachedFractionAlignment(numalignAttr, m_numeratorAlignment);
}

MathMLFractionElement::FractionAlignment MathMLFractionElement::denominatorAlignment()
{
    return cachedFractionAlignment(denomalignAttr, m_denominatorAlignment);
}

void MathMLFractionElement::parseAttribute(const QualifiedName& name, const AtomString& value)
{
    if (name == linethicknessAttr)
        m_lineThickness = std::nullopt;
    else if (name == numalignAttr)
        m_numeratorAlignment = std::nullopt;
    else if (name == denomalignAttr)
        m_denominatorAlignment = std::nullopt;

    MathMLElement::parseAttribute(name, value);
}

RenderPtr<RenderElement> MathMLFractionElement::createElementRenderer(RenderStyle&& style, const RenderTreePosition&)
{
    ASSERT(hasTagName(MathMLNames::mfracTag));
    return createRenderer<RenderMathMLFraction>(*this, WTFMove(style));
}

}

#endif // ENABLE(MATHML)