/****************************************************************************
**
** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
** Contact: http://www.qt-project.org/legal
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** This file is part of the Qt3D module of the Qt Toolkit.
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** $QT_BEGIN_LICENSE:LGPL3$
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** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPLv3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or later as published by the Free
** Software Foundation and appearing in the file LICENSE.GPL included in
** the packaging of this file. Please review the following information to
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****************************************************************************/

#ifndef QT3D_QFRAMEALLOCATOR_P_H
#define QT3D_QFRAMEALLOCATOR_P_H

#include <Qt3DCore/qt3dcore_global.h>

QT_BEGIN_NAMESPACE

namespace Qt3D {

class QFrameAllocator;

struct Q_AUTOTEST_EXPORT QFrameChunk
{
    void init(uint blockSize, uchar blocks);
    void *allocate(uint blockSize);

    void deallocate(void *p, uint blockSize);
    bool contains(void *p, uint blockSize);
    void clear(uint blockSize, uchar blocks);
    void release();

    inline bool isEmpty() const { return m_blocksAvailable == m_maxBlocksAvailable; }

    uchar *m_data;
    uchar  m_firstAvailableBlock;
    uchar  m_blocksAvailable;
    uchar  m_maxBlocksAvailable;
};

class Q_AUTOTEST_EXPORT QFixedFrameAllocator
{
public:
    QFixedFrameAllocator();
    ~QFixedFrameAllocator();

    void init(uint blockSize, uchar pageSize = 128);
    void *allocate();
    void  deallocate(void *ptr);
    void trim();
    void release();
    void clear();

    inline int chunkCount() const { return m_chunks.size(); }
    inline uchar pageSize() const { return m_nbrBlock; }
    inline uint blockSize() const { return m_blockSize; }

private:
    uint m_blockSize;
    uchar m_nbrBlock;
    QVector<QFrameChunk> m_chunks;
    QFrameChunk *m_lastAllocatedChunck;
    QFrameChunk *m_lastFreedChunck;
};

class QFrameAllocatorPrivate
{
public:
    QFrameAllocatorPrivate(QFrameAllocator *qq);

    inline void *allocateAtChunk(uint allocatorIndex)
    {
        return m_allocatorPool[allocatorIndex].allocate();
    }

    inline void deallocateAtChunck(void *ptr, uint allocatorIndex)
    {
        m_allocatorPool[allocatorIndex].deallocate(ptr);
    }

    inline uint allocatorIndexFromSize(uint targetSize) const
    {
        return (targetSize + m_alignment - 1) / m_alignment - 1;
    }

    Q_DECLARE_PUBLIC(QFrameAllocator)
    QFrameAllocator *q_ptr;

    uint m_maxObjectSize;
    uint m_alignment;
    QVector<QFixedFrameAllocator> m_allocatorPool;
};

} // Qt3D

QT_END_NAMESPACE

#endif // QT3D_QFRAMEALLOCATOR_P_H