text: /*
   * Copyright (C) 2011 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef THIRD_PARTY_BLINK_RENDERER_CORE_CSS_CSS_CROSSFADE_VALUE_H_
  #define THIRD_PARTY_BLINK_RENDERER_CORE_CSS_CSS_CROSSFADE_VALUE_H_
  
  #include "third_party/blink/renderer/core/core_export.h"
  #include "third_party/blink/renderer/core/css/css_image_generator_value.h"
  #include "third_party/blink/renderer/core/css/css_primitive_value.h"
  #include "third_party/blink/renderer/core/loader/resource/image_resource_content.h"
  #include "third_party/blink/renderer/core/loader/resource/image_resource_observer.h"
  #include "third_party/blink/renderer/platform/graphics/image.h"
  #include "third_party/blink/renderer/platform/wtf/casting.h"
  
  namespace blink {
  
  class CrossfadeSubimageObserverProxy;
  
  namespace cssvalue {
  
  class CORE_EXPORT CSSCrossfadeValue final : public CSSImageGeneratorValue {
    friend class blink::CrossfadeSubimageObserverProxy;
    USING_PRE_FINALIZER(CSSCrossfadeValue, Dispose);
  
   public:
    CSSCrossfadeValue(CSSValue* from_value,
                      CSSValue* to_value,
                      CSSPrimitiveValue* percentage_value);
    ~CSSCrossfadeValue();
  
    String CustomCSSText() const;
  
    scoped_refptr<Image> GetImage(const ImageResourceObserver&,
                                  const Document&,
                                  const ComputedStyle&,
                                  const FloatSize& target_size) const;
    bool IsFixedSize() const { return true; }
    FloatSize FixedSize(const Document&, const FloatSize&) const;
  
    bool IsPending() const;
    bool KnownToBeOpaque(const Document&, const ComputedStyle&) const;
  
    void LoadSubimages(const Document&);
  
    bool HasFailedOrCanceledSubresources() const;
  
    bool Equals(const CSSCrossfadeValue&) const;
  
    CSSCrossfadeValue* ComputedCSSValue(const ComputedStyle&,
                                        bool allow_visited_style);
  
    void TraceAfterDispatch(blink::Visitor*) const;
  
   private:
    void Dispose();
  
    class CrossfadeSubimageObserverProxy final : public ImageResourceObserver {
      DISALLOW_NEW();
  
     public:
      explicit CrossfadeSubimageObserverProxy(CSSCrossfadeValue* owner_value)
          : owner_value_(owner_value), ready_(false) {}
  
      ~CrossfadeSubimageObserverProxy() override = default;
      void Trace(Visitor* visitor) { visitor->Trace(owner_value_); }
  
      void ImageChanged(ImageResourceContent*, CanDeferInvalidation) override;
      bool WillRenderImage() override;
      String DebugName() const override {
        return "CrossfadeSubimageObserverProxy";
      }
      void SetReady(bool ready) { ready_ = ready; }
  
     private:
      Member<CSSCrossfadeValue> owner_value_;
      bool ready_;
    };
  
    bool WillRenderImage() const;
    void CrossfadeChanged(ImageResourceObserver::CanDeferInvalidation);
  
    Member<CSSValue> from_value_;
    Member<CSSValue> to_value_;
    Member<CSSPrimitiveValue> percentage_value_;
  
    Member<ImageResourceContent> cached_from_image_;
    Member<ImageResourceContent> cached_to_image_;
  
    CrossfadeSubimageObserverProxy crossfade_subimage_observer_;
  };
  
  }  // namespace cssvalue
  
  template <>
  struct DowncastTraits<cssvalue::CSSCrossfadeValue> {
    static bool AllowFrom(const CSSValue& value) {
      return value.IsCrossfadeValue();
    }
  };
  
  }  // namespace blink
  
  #endif  // THIRD_PARTY_BLINK_RENDERER_CORE_CSS_CSS_CROSSFADE_VALUE_H_
  