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****************************************************************************/

#ifndef FILESAVER_H
#define FILESAVER_H

#include <QtCore/qbuffer.h>
#include <QtCore/qbytearray.h>
#include <QtCore/qscopedpointer.h>
#include <QtCore/qstring.h>

namespace qbs {
namespace Internal {

/*!
 * QSaveFile wrapper which doesn't update the target file if the contents are unchanged.
 */
class FileSaver {
public:
    FileSaver(const QString &filePath, bool overwriteIfUnchanged = false);

    QIODevice *device();
    bool open();
    bool commit();
    qint64 write(const QByteArray &data);

private:
    QByteArray m_newFileContents;
    QByteArray m_oldFileContents;
    QScopedPointer<QBuffer> m_memoryDevice;
    const QString m_filePath;
    const bool m_overwriteIfUnchanged;
};

} // namespace Internal
} // namespace qbs

#endif // FILESAVER_H
