#ifndef Canvas2DLayerBridge_h
#define Canvas2DLayerBridge_h
#include "SkDeferredCanvas.h"
#include "SkImage.h"
#include "platform/PlatformExport.h"
#include "platform/geometry/IntSize.h"
#include "platform/graphics/ImageBufferSurface.h"
#include "public/platform/WebExternalTextureLayer.h"
#include "public/platform/WebExternalTextureLayerClient.h"
#include "public/platform/WebExternalTextureMailbox.h"
#include "third_party/khronos/GLES2/gl2.h"
#include "wtf/DoublyLinkedList.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/RefCounted.h"
#include "wtf/RefPtr.h"
namespace blink {
class WebGraphicsContext3D;
class WebGraphicsContext3DProvider;
}
class Canvas2DLayerBridgeTest;
namespace WebCore {
class ImageBuffer;
class PLATFORM_EXPORT Canvas2DLayerBridge : public blink::WebExternalTextureLayerClient, public SkDeferredCanvas::NotificationClient, public DoublyLinkedListNode<Canvas2DLayerBridge>, public RefCounted<Canvas2DLayerBridge> {
    WTF_MAKE_NONCOPYABLE(Canvas2DLayerBridge);
public:
    static PassRefPtr<Canvas2DLayerBridge> create(const IntSize&, OpacityMode, int msaaSampleCount);
    virtual ~Canvas2DLayerBridge();
    
    virtual blink::WebGraphicsContext3D* context() OVERRIDE;
    virtual bool prepareMailbox(blink::WebExternalTextureMailbox*, blink::WebExternalBitmap*) OVERRIDE;
    virtual void mailboxReleased(const blink::WebExternalTextureMailbox&) OVERRIDE;
    
    virtual void prepareForDraw() OVERRIDE;
    virtual void storageAllocatedForRecordingChanged(size_t) OVERRIDE;
    virtual void flushedDrawCommands() OVERRIDE;
    virtual void skippedPendingDrawCommands() OVERRIDE;
    
    void willUse();
    SkCanvas* canvas() const { return m_canvas.get(); }
    bool checkSurfaceValid();
    bool restoreSurface();
    blink::WebLayer* layer() const;
    Platform3DObject getBackingTexture();
    bool isAccelerated() const { return true; }
    void setIsHidden(bool);
    void setImageBuffer(ImageBuffer* imageBuffer) { m_imageBuffer = imageBuffer; }
    
    virtual size_t freeMemoryIfPossible(size_t); 
    virtual void flush(); 
    virtual size_t storageAllocatedForRecording(); 
    size_t bytesAllocated() const { return m_bytesAllocated; }
    void limitPendingFrames();
    void freeReleasedMailbox();
    bool hasReleasedMailbox() const;
    void freeTransientResources();
    bool hasTransientResources() const;
    bool isHidden() { return m_isHidden; }
    void beginDestruction();
protected:
    Canvas2DLayerBridge(PassOwnPtr<blink::WebGraphicsContext3DProvider>, PassOwnPtr<SkDeferredCanvas>, int, OpacityMode);
    void setRateLimitingEnabled(bool);
    bool releasedMailboxHasExpired();
    OwnPtr<SkDeferredCanvas> m_canvas;
    OwnPtr<blink::WebExternalTextureLayer> m_layer;
    OwnPtr<blink::WebGraphicsContext3DProvider> m_contextProvider;
    ImageBuffer* m_imageBuffer;
    int m_msaaSampleCount;
    size_t m_bytesAllocated;
    bool m_didRecordDrawCommand;
    bool m_isSurfaceValid;
    int m_framesPending;
    int m_framesSinceMailboxRelease;
    bool m_destructionInProgress;
    bool m_rateLimitingEnabled;
    bool m_isHidden;
    friend class WTF::DoublyLinkedListNode<Canvas2DLayerBridge>;
    friend class ::Canvas2DLayerBridgeTest;
    Canvas2DLayerBridge* m_next;
    Canvas2DLayerBridge* m_prev;
    enum MailboxStatus {
        MailboxInUse,
        MailboxReleased,
        MailboxAvailable,
    };
    struct MailboxInfo {
        blink::WebExternalTextureMailbox m_mailbox;
        RefPtr<SkImage> m_image;
        MailboxStatus m_status;
        RefPtr<Canvas2DLayerBridge> m_parentLayerBridge;
        MailboxInfo(const MailboxInfo&);
        MailboxInfo() {}
    };
    MailboxInfo* createMailboxInfo();
    MailboxInfo* releasedMailboxInfo();
    uint32_t m_lastImageId;
    Vector<MailboxInfo> m_mailboxes;
    int m_releasedMailboxInfoIndex;
};
}
#endif