third_party/WebKit/Source/core/css/CSSCalculationValue.h

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#ifndef CSSCalculationValue_h
#define CSSCalculationValue_h

#include "core/CoreExport.h"
#include "core/css/CSSPrimitiveValue.h"
#include "core/css/CSSValue.h"
#include "core/css/parser/CSSParserTokenRange.h"
#include "platform/CalculationValue.h"
#include "wtf/Forward.h"

namespace blink {

class CalculationValue;

enum CalcOperator {
  CalcAdd = '+',
  CalcSubtract = '-',
  CalcMultiply = '*',
  CalcDivide = '/'
};

// The order of this enum should not change since its elements are used as
// indices in the addSubtractResult matrix.
enum CalculationCategory {
  CalcNumber = 0,
  CalcLength,
  CalcPercent,
  CalcPercentNumber,
  CalcPercentLength,
  CalcAngle,
  CalcTime,
  CalcFrequency,
  CalcLengthNumber,
  CalcPercentLengthNumber,
  CalcOther
};

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

  virtual bool isZero() const = 0;
  virtual double doubleValue() const = 0;
  virtual double computeLengthPx(const CSSToLengthConversionData&) const = 0;
  virtual void accumulateLengthArray(CSSLengthArray&,
                                     double multiplier) const = 0;
  virtual void accumulatePixelsAndPercent(const CSSToLengthConversionData&,
                                          PixelsAndPercent&,
                                          float multiplier = 1) 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 getType() const = 0;

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

  DEFINE_INLINE_VIRTUAL_TRACE() {}

 protected:
  CSSCalcExpressionNode(CalculationCategory category, bool isInteger)
      : m_category(category), m_isInteger(isInteger) {
    ASSERT(category != CalcOther);
  }

  CalculationCategory m_category;
  bool m_isInteger;
};

class CORE_EXPORT CSSCalcValue : public GarbageCollected<CSSCalcValue> {
 public:
  static CSSCalcValue* create(const CSSParserTokenRange&, ValueRange);
  static CSSCalcValue* create(CSSCalcExpressionNode*,
                              ValueRange = ValueRangeAll);

  static CSSCalcExpressionNode* createExpressionNode(CSSPrimitiveValue*,
                                                     bool isInteger = false);
  static CSSCalcExpressionNode* createExpressionNode(CSSCalcExpressionNode*,
                                                     CSSCalcExpressionNode*,
                                                     CalcOperator);
  static CSSCalcExpressionNode* createExpressionNode(double pixels,
                                                     double percent);

  PassRefPtr<CalculationValue> toCalcValue(
      const CSSToLengthConversionData& conversionData) const {
    PixelsAndPercent value(0, 0);
    m_expression->accumulatePixelsAndPercent(conversionData, value);
    return CalculationValue::create(
        value, 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 CSSToLengthConversionData&) const;
  void accumulateLengthArray(CSSLengthArray& lengthArray,
                             double multiplier) const {
    m_expression->accumulateLengthArray(lengthArray, multiplier);
  }
  CSSCalcExpressionNode* expressionNode() const { return m_expression.get(); }

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

  DEFINE_INLINE_TRACE() { visitor->trace(m_expression); }

 private:
  CSSCalcValue(CSSCalcExpressionNode* expression, ValueRange range)
      : m_expression(expression),
        m_nonNegative(range == ValueRangeNonNegative) {}

  double clampToPermittedRange(double) const;

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

}  // namespace blink

#endif  // CSSCalculationValue_h