Source/WebCore/css/CSSCalculationValue.h

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#pragma once

#include "CSSPrimitiveValue.h"
#include "CalculationValue.h"

namespace WebCore {

class CSSParserTokenRange;
class CSSToLengthConversionData;
class RenderStyle;

enum CalculationCategory {
    CalcNumber = 0,
    CalcLength,
    CalcPercent,
    CalcPercentNumber,
    CalcPercentLength,
    CalcAngle,
    CalcTime,
    CalcFrequency,
    CalcOther
};

class CSSCalcExpressionNode : public RefCounted<CSSCalcExpressionNode> {
public:
    enum Type {
        CssCalcPrimitiveValue = 1,
        CssCalcOperation
    };

    virtual ~CSSCalcExpressionNode() = default;
    virtual bool isZero() const = 0;
    virtual std::unique_ptr<CalcExpressionNode> createCalcExpression(const CSSToLengthConversionData&) const = 0;
    virtual double doubleValue() const = 0;
    virtual double computeLengthPx(const CSSToLengthConversionData&) const = 0;
    virtual String customCSSText() const = 0;
    virtual bool equals(const CSSCalcExpressionNode& other) const { return m_category == other.m_category && m_isInteger == other.m_isInteger; }
    virtual Type type() const = 0;
    virtual CSSPrimitiveValue::UnitType primitiveType() const = 0;

    CalculationCategory category() const { return m_category; }
    bool isInteger() const { return m_isInteger; }

protected:
    CSSCalcExpressionNode(CalculationCategory category, bool isInteger)
        : m_category(category)
        , m_isInteger(isInteger)
    {
    }

private:
    CalculationCategory m_category;
    bool m_isInteger;
};

class CSSCalcValue final : public CSSValue {
public:
    static RefPtr<CSSCalcValue> create(CSSValueID function, const CSSParserTokenRange&, CalculationCategory destinationCategory, ValueRange);

    static RefPtr<CSSCalcValue> create(const CalculationValue&, const RenderStyle&);

    CalculationCategory category() const { return m_expression->category(); }
    bool isInt() const { return m_expression->isInteger(); }
    double doubleValue() const;
    bool isPositive() const { return m_expression->doubleValue() > 0; }
    bool isNegative() const { return m_expression->doubleValue() < 0; }
    double computeLengthPx(const CSSToLengthConversionData&) const;
    unsigned short primitiveType() const { return m_expression->primitiveType(); }

    Ref<CalculationValue> createCalculationValue(const CSSToLengthConversionData&) const;
    void setPermittedValueRange(ValueRange);

    String customCSSText() const;
    bool equals(const CSSCalcValue&) const;

private:
    CSSCalcValue(Ref<CSSCalcExpressionNode>&&, bool shouldClampToNonNegative);

    double clampToPermittedRange(double) const;

    const Ref<CSSCalcExpressionNode> m_expression;
    bool m_shouldClampToNonNegative;
};

inline CSSCalcValue::CSSCalcValue(Ref<CSSCalcExpressionNode>&& expression, bool shouldClampToNonNegative)
    : CSSValue(CalculationClass)
    , m_expression(WTFMove(expression))
    , m_shouldClampToNonNegative(shouldClampToNonNegative)
{
}

inline Ref<CalculationValue> CSSCalcValue::createCalculationValue(const CSSToLengthConversionData& conversionData) const
{
    return CalculationValue::create(m_expression->createCalcExpression(conversionData),
        m_shouldClampToNonNegative ? ValueRangeNonNegative : ValueRangeAll);
}

inline void CSSCalcValue::setPermittedValueRange(ValueRange range)
{
    m_shouldClampToNonNegative = range != ValueRangeAll;
}

} // namespace WebCore

SPECIALIZE_TYPE_TRAITS_CSS_VALUE(CSSCalcValue, isCalcValue())