Source/core/css/CSSCalculationValue.h

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#ifndef CSSCalculationValue_h
#define CSSCalculationValue_h

#include "core/css/CSSParserValues.h"
#include "core/css/CSSPrimitiveValue.h"
#include "core/css/CSSValue.h"
#include "core/platform/CalculationValue.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/RefCounted.h"
#include "wtf/RefPtr.h"

namespace WebCore {

class CSSParserValueList;
class CSSValueList;
class CalculationValue;
class CalcExpressionNode;
class RenderStyle;
struct Length;

enum CalculationCategory {
    CalcNumber = 0,
    CalcLength,
    CalcPercent,
    CalcPercentNumber,
    CalcPercentLength,
    CalcVariable,
    CalcOther
};

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

    virtual ~CSSCalcExpressionNode() = 0;
    virtual bool isZero() const = 0;
    virtual PassOwnPtr<CalcExpressionNode> toCalcValue(const RenderStyle*, const RenderStyle* rootStyle, double zoom = 1.0) const = 0;
    virtual double doubleValue() const = 0;
    virtual double computeLengthPx(const RenderStyle* currentStyle, const RenderStyle* rootStyle, double multiplier = 1.0, bool computingFontSize = false) const = 0;
    virtual String customCssText() const = 0;
    virtual String serializeResolvingVariables(const HashMap<AtomicString, String>&) const = 0;
    virtual bool hasVariableReference() 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;

    CalculationCategory category() const { return m_category; }
    virtual CSSPrimitiveValue::UnitTypes primitiveType() const = 0;
    bool isInteger() const { return m_isInteger; }

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

    CalculationCategory m_category;
    bool m_isInteger;
};

class CSSCalcValue : public CSSValue {
public:
    static PassRefPtr<CSSCalcValue> create(CSSParserString name, CSSParserValueList*, ValueRange);
    static PassRefPtr<CSSCalcValue> create(PassRefPtr<CSSCalcExpressionNode>, ValueRange = ValueRangeAll);
    static PassRefPtr<CSSCalcValue> create(const CalculationValue* value, float zoom) { return adoptRef(new CSSCalcValue(value, zoom)); }

    static PassRefPtr<CSSCalcExpressionNode> createExpressionNode(PassRefPtr<CSSPrimitiveValue>, bool isInteger = false);
    static PassRefPtr<CSSCalcExpressionNode> createExpressionNode(PassRefPtr<CSSCalcExpressionNode>, PassRefPtr<CSSCalcExpressionNode>, CalcOperator);
    static PassRefPtr<CSSCalcExpressionNode> createExpressionNode(const CalcExpressionNode*, float zoom);
    static PassRefPtr<CSSCalcExpressionNode> createExpressionNode(const Length&, float zoom);

    PassRefPtr<CalculationValue> toCalcValue(const RenderStyle* style, const RenderStyle* rootStyle, double zoom = 1.0) const
    {
        return CalculationValue::create(m_expression->toCalcValue(style, rootStyle, zoom), m_nonNegative ? ValueRangeNonNegative : ValueRangeAll);
    }
    CalculationCategory category() const { return m_expression->category(); }
    bool isInt() const { return m_expression->isInteger(); }
    double doubleValue() const;
    bool isNegative() const { return m_expression->doubleValue() < 0; }
    ValueRange permittedValueRange() { return m_nonNegative ? ValueRangeNonNegative : ValueRangeAll; }
    double computeLengthPx(const RenderStyle* currentStyle, const RenderStyle* rootStyle, double multiplier = 1.0, bool computingFontSize = false) const;
    CSSCalcExpressionNode* expressionNode() const { return m_expression.get(); }

    String customCssText() const;
    bool equals(const CSSCalcValue&) const;
    String customSerializeResolvingVariables(const HashMap<AtomicString, String>&) const;
    bool hasVariableReference() const;

private:
    CSSCalcValue(PassRefPtr<CSSCalcExpressionNode> expression, ValueRange range)
        : CSSValue(CalculationClass)
        , m_expression(expression)
        , m_nonNegative(range == ValueRangeNonNegative)
    {
    }
    CSSCalcValue(const CalculationValue* value, float zoom)
        : CSSValue(CalculationClass)
        , m_expression(createExpressionNode(value->expression(), zoom))
        , m_nonNegative(value->isNonNegative())
    {
    }

    double clampToPermittedRange(double) const;

    const RefPtr<CSSCalcExpressionNode> m_expression;
    const bool m_nonNegative;
};

DEFINE_CSS_VALUE_TYPE_CASTS(CalcValue);

} // namespace WebCore


#endif // CSSCalculationValue_h