Source/WebCore/css/CSSCalculationValue.h

/*
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 */

#pragma once

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

namespace WTF {
class TextStream;
}

namespace WebCore {

class CSSParserTokenRange;
class CSSToLengthConversionData;
class RenderStyle;

// FIXME: Unify with CSSPrimitiveValue::UnitCategory.
enum class CalculationCategory : uint8_t {
    Number = 0,
    Length,
    Percent,
    PercentNumber,
    PercentLength,
    Angle,
    Time,
    Frequency,
    // TODO:
    // Flex,
    // Resolution
    Other
};

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

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

    virtual void collectDirectComputationalDependencies(HashSet<CSSPropertyID>&) const = 0;
    virtual void collectDirectRootComputationalDependencies(HashSet<CSSPropertyID>&) const = 0;

    CalculationCategory category() const { return m_category; }

    virtual void dump(TextStream&) const = 0;

protected:
    CSSCalcExpressionNode(CalculationCategory category)
        : m_category(category)
    {
    }

private:
    CalculationCategory m_category;
};

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(); }
    double doubleValue() const;
    double computeLengthPx(const CSSToLengthConversionData&) const;
    CSSUnitType primitiveType() const { return m_expression->primitiveType(); }

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

    void collectDirectComputationalDependencies(HashSet<CSSPropertyID>&) const;
    void collectDirectRootComputationalDependencies(HashSet<CSSPropertyID>&) const;

    String customCSSText() const;
    bool equals(const CSSCalcValue&) const;
    
    static bool isCalcFunction(CSSValueID);

    void dump(TextStream&) 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;
}

inline void CSSCalcValue::collectDirectComputationalDependencies(HashSet<CSSPropertyID>& values) const
{
    m_expression->collectDirectComputationalDependencies(values);
}

inline void CSSCalcValue::collectDirectRootComputationalDependencies(HashSet<CSSPropertyID>& values) const
{
    m_expression->collectDirectRootComputationalDependencies(values);
}

WTF::TextStream& operator<<(WTF::TextStream&, CalculationCategory);
WTF::TextStream& operator<<(WTF::TextStream&, const CSSCalcValue&);

} // namespace WebCore

SPECIALIZE_TYPE_TRAITS_CSS_VALUE(CSSCalcValue, isCalcValue())

#define SPECIALIZE_TYPE_TRAITS_CSSCALCEXPRESSION_NODE(ToValueTypeName, predicate) \
SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::ToValueTypeName) \
    static bool isType(const WebCore::CSSCalcExpressionNode& node) { return node.predicate; } \
SPECIALIZE_TYPE_TRAITS_END()