/* This file is part of the KDE libraries

   SPDX-FileCopyrightText: 2001, 2002, 2007 David Faure <faure@kde.org>

   SPDX-License-Identifier: LGPL-2.0-or-later

*/

#ifndef klimitediodevice_p_h

#define klimitediodevice_p_h

#include <QDebug>

#include <QIODevice>

/*!

 * A readonly device that reads from an underlying device

 * from a given point to another (e.g. to give access to a single

 * file inside an archive).

 * @author David Faure <faure@kde.org>

 * \internal - used by KArchive

 */

class KLimitedIODevice : public QIODevice

{

    Q_OBJECT

public:

    /*!

     * Creates a new KLimitedIODevice.

     * \a dev the underlying device, opened or not

     * This device itself auto-opens (in readonly mode), no need to open it.

     * \a start where to start reading (position in bytes)

     * \a length the length of the data to read (in bytes)

     */

    KLimitedIODevice(QIODevice *dev, qint64 start, qint64 length);

    ~KLimitedIODevice() override

    {

    }

    bool isSequential() const override;

    [[nodiscard]] bool open(QIODevice::OpenMode m) override;

    void close() override;

    qint64 size() const override;

    qint64 readData(char *data, qint64 maxlen) override;

    qint64 writeData(const char *, qint64) override

    {

        return -1; // unsupported

    }

    // virtual qint64 pos() const { return m_dev->pos() - m_start; }

    bool seek(qint64 pos) override;

    qint64 bytesAvailable() const override;

private:

    QIODevice *m_dev;

    const qint64 m_start;

    const qint64 m_length;

};

#endif