/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**

 * An ISurfaceProvider implemented for single-frame decoded surfaces.

 */

#ifndef mozilla_image_DecodedSurfaceProvider_h

#define mozilla_image_DecodedSurfaceProvider_h

#include "IDecodingTask.h"

#include "ISurfaceProvider.h"

#include "SurfaceCache.h"

namespace mozilla {

namespace image {

/**

 * An ISurfaceProvider that manages the decoding of a single-frame image and

 * stores the resulting surface.

 */

class DecodedSurfaceProvider final

  : public ISurfaceProvider

  , public IDecodingTask

{

public:

  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(DecodedSurfaceProvider, override)

  DecodedSurfaceProvider(NotNull<RasterImage*> aImage,

                         const SurfaceKey& aSurfaceKey,

                         NotNull<Decoder*> aDecoder);

  //////////////////////////////////////////////////////////////////////////////

  // ISurfaceProvider implementation.

  //////////////////////////////////////////////////////////////////////////////

public:

  bool IsFinished() const override;

  size_t LogicalSizeInBytes() const override;

protected:

  DrawableFrameRef DrawableRef(size_t aFrame) override;

  bool IsLocked() const override { return bool(mLockRef); }

  void SetLocked(bool aLocked) override;

  //////////////////////////////////////////////////////////////////////////////

  // IDecodingTask implementation.

  //////////////////////////////////////////////////////////////////////////////

public:

  void Run() override;

  bool ShouldPreferSyncRun() const override;

  // Full decodes are low priority compared to metadata decodes because they

  // don't block layout or page load.

  TaskPriority Priority() const override { return TaskPriority::eLow; }

private:

  virtual ~DecodedSurfaceProvider();

  void DropImageReference();

  void CheckForNewSurface();

  void FinishDecoding();

  /// The image associated with our decoder. Dropped after decoding.

  RefPtr<RasterImage> mImage;

  /// Mutex protecting access to mDecoder.

  Mutex mMutex;

  /// The decoder that will generate our surface. Dropped after decoding.

  RefPtr<Decoder> mDecoder;

  /// Our surface. Initially null until it's generated by the decoder.

  RefPtr<imgFrame> mSurface;

  /// A drawable reference to our service; used for locking.

  DrawableFrameRef mLockRef;

};

} // namespace image

} // namespace mozilla

#endif // mozilla_image_DecodedSurfaceProvider_h