chromium/src/third_party/blink/renderer/core/css/style_color.h

/*
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 * in the documentation and/or other materials provided with the
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#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_CSS_STYLE_COLOR_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_CSS_STYLE_COLOR_H_

#include "third_party/blink/public/mojom/frame/color_scheme.mojom-blink-forward.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/css_value_keywords.h"
#include "third_party/blink/renderer/platform/graphics/color.h"
#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"

namespace blink {

class CORE_EXPORT StyleColor {
  DISALLOW_NEW();

 public:
  StyleColor() = default;
  explicit StyleColor(Color color)
      : color_(color), color_keyword_(CSSValueID::kInvalid) {}
  explicit StyleColor(RGBA32 color)
      : color_(color), color_keyword_(CSSValueID::kInvalid) {}
  explicit StyleColor(CSSValueID keyword) : color_keyword_(keyword) {}
  // TODO(1081945): We need to store the color and keyword for system colors
  // to allow forced colors mode to access system color keywords while the
  // CSSSystemColorComputeToSelf feature is under development. Once
  // CSSSystemColorComputeToSelf is enabled, we can remove this ctr and
  // EffectiveColorKeyword() and use color_keyword_ directly, instead.
  StyleColor(Color color, CSSValueID keyword)
      : color_(color), color_keyword_(keyword) {}
  static StyleColor CurrentColor() { return StyleColor(); }

  bool IsCurrentColor() const {
    return color_keyword_ == CSSValueID::kCurrentcolor;
  }
  bool IsSystemColor() const { return IsSystemColor(color_keyword_); }
  Color GetColor() const {
    DCHECK(IsNumeric());
    return color_;
  }
  CSSValueID GetColorKeyword() const {
    DCHECK(!IsNumeric());
    return color_keyword_;
  }

  // TODO(1081945):  Once CSSSystemColorComputeToSelf is enabled, we can remove
  // |is_forced_color|.
  Color Resolve(Color current_color,
                mojom::blink::ColorScheme color_scheme,
                bool is_forced_color = false) const;

  // Resolve and override the resolved color's alpha channel as specified by
  // |alpha|.
  // TODO(1081945):  Once CSSSystemColorComputeToSelf is enabled, we can remove
  // |is_forced_color|.
  Color ResolveWithAlpha(Color current_color,
                         mojom::blink::ColorScheme color_scheme,
                         int alpha,
                         bool is_forced_color = false) const;

  bool IsNumeric() const {
    return EffectiveColorKeyword() == CSSValueID::kInvalid;
  }

  static Color ColorFromKeyword(CSSValueID,
                                mojom::blink::ColorScheme color_scheme);
  static bool IsColorKeyword(CSSValueID);
  static bool IsSystemColor(CSSValueID);

  inline bool operator==(const StyleColor& other) const {
    DCHECK(IsValid());
    DCHECK(other.IsValid());
    return color_ == other.color_ && color_keyword_ == other.color_keyword_;
  }

  inline bool operator!=(const StyleColor& other) const {
    return !(*this == other);
  }

 protected:
  inline bool IsValid() const {
    // At least one of color_keyword_ and color_ should retain its default
    // value.
    return EffectiveColorKeyword() == CSSValueID::kInvalid ||
           color_ == Color() || IsSystemColor(EffectiveColorKeyword());
  }

  Color color_;
  CSSValueID color_keyword_ = CSSValueID::kCurrentcolor;

 private:
  CSSValueID EffectiveColorKeyword() const;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_CSS_STYLE_COLOR_H_