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#ifndef QSSG_RENDER_THREADED_IMAGE_LOADER_H
#define QSSG_RENDER_THREADED_IMAGE_LOADER_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtQuick3DUtils/private/qssgdataref_p.h>
#include <QtQuick3DRender/private/qssgrenderbasetypes_p.h>

QT_BEGIN_NAMESPACE
enum class ImageLoadResult
{
    Succeeded,
    Failed,
};

class IImageLoadListener
{
public:
    QAtomicInt ref;
    virtual ~IImageLoadListener() {}
    virtual void OnImageLoadComplete(QString inPath, ImageLoadResult inResult) = 0;
    virtual void OnImageBatchComplete(quint64 inBatch) = 0;
};

typedef quint32 TImageBatchId;

class QSSGInputStreamFactory;
class QSSGBufferManager;
class QSSGAbstractThreadPool;
class QSSGPerfTimer;
class IImageBatchLoader
{
public:
    QAtomicInt ref;
    virtual ~IImageBatchLoader() {}
    // Returns an ID to the load request.  Request a block of images to be loaded.
    // Also takes an image that the buffer system will return when requested for the given
    // source paths
    // until said path is loaded.
    // An optional listener can be passed in to get callbacks about the batch.
    virtual TImageBatchId loadImageBatch(QSSGDataView<QString> inSourcePaths,
                                         QString inImageTillLoaded,
                                         IImageLoadListener *inListener,
                                         QSSGRenderContextType type) = 0;
    // Blocks if any of the images in the batch are in flight
    virtual void cancelImageBatchLoading(TImageBatchId inBatchId) = 0;
    // Blocks if the image is currently in-flight
    virtual void cancelImageLoading(QString inSourcePath) = 0;
    // Block until every image in the batch is loaded.
    virtual void blockUntilLoaded(TImageBatchId inId) = 0;

    // These are called by the render context, users don't need to call this.
    virtual void beginFrame() = 0;
    virtual void endFrame() = 0;

    static QSSGRef<IImageBatchLoader> createBatchLoader(QSSGRef<QSSGInputStreamFactory> inFactory,
                                                          QSSGRef<QSSGBufferManager> inBufferManager,
                                                          QSSGRef<QSSGAbstractThreadPool> inThreadPool,
                                                          QSSGPerfTimer *inTimer);
};
QT_END_NAMESPACE

#endif
