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#ifndef QT3DCORE_QTHREADPOOLER_H
#define QT3DCORE_QTHREADPOOLER_H

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

#include <QtCore/QFuture>
#include <QtCore/QFutureInterface>
#include <QtCore/QObject>
#include <QtCore/QSharedPointer>
#include <QtCore/QThreadPool>

#include <Qt3DCore/private/qaspectjob_p.h>
#include <Qt3DCore/private/task_p.h>

#ifdef QT3D_JOBS_RUN_STATS
#include <QtCore/QElapsedTimer>
#endif

QT_BEGIN_NAMESPACE

namespace Qt3DCore {

class QT3DCORE_PRIVATE_EXPORT QThreadPooler : public QObject
{
    Q_OBJECT

public:
    explicit QThreadPooler(QObject *parent = 0);
    ~QThreadPooler();

    QFuture<void> mapDependables(QVector<RunnableInterface *> &taskQueue);
    void taskFinished(RunnableInterface *task);
    QFuture<void> future();

    int maxThreadCount() const;
#ifdef QT3D_JOBS_RUN_STATS
    static QElapsedTimer m_jobsStatTimer;

    // Aspects + Job threads
    static void addJobLogStatsEntry(JobRunStats &stats);
    static void writeFrameJobLogStats();

    // Submission thread
    static void addSubmissionLogStatsEntry(JobRunStats &stats);

#endif

private:
    void enqueueTasks(const QVector<RunnableInterface *> &tasks);
    void acquire(int add);
    void release();
    int currentCount() const;

private:
    QFutureInterface<void> *m_futureInterface;
    QMutex m_mutex;
    QAtomicInt m_taskCount;
    QThreadPool m_threadPool;
};

} // namespace Qt3DCore

QT_END_NAMESPACE

#endif // QT3DCORE_QTHREADPOOLER_H
