/*********************************************************************/
// dar - disk archive - a backup/restoration program
// Copyright (C) 2002-2052 Denis Corbin
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
//
// to contact the author : dar.linux@free.fr
/*********************************************************************/
// $Id: scrambler.hpp,v 1.10.2.1 2007/07/22 16:35:00 edrusb Rel $
//
/*********************************************************************/

    /// \file scrambler.hpp
    /// \brief contains the definition of the scrambler class, a very weak encryption scheme

#ifndef SCRAMBLER_HPP
#define SCRAMBLER_HPP

#include "/usr/include/dar/my_config.h"
#include <string>
#include "/usr/include/dar/infinint.hpp"
#include "/usr/include/dar/generic_file.hpp"
#include "/usr/include/dar/erreurs.hpp"
#include "/usr/include/dar/infinint.hpp"

namespace libdar
{

	/// \brief scrambler is a very weak encryption scheme
	/// \ingroup Private

    class scrambler : public generic_file
    {
    public:
        scrambler(user_interaction & dialog, const std::string & pass, generic_file & hidden_side);
        ~scrambler() { if(buffer != NULL) delete [] buffer; };

        bool skip(const infinint & pos) { if(ref == NULL) throw SRC_BUG; return ref->skip(pos); };
        bool skip_to_eof() { if(ref==NULL) throw SRC_BUG; return ref->skip_to_eof(); };
        bool skip_relative(S_I x) { if(ref == NULL) throw SRC_BUG; return ref->skip_relative(x); };
        infinint get_position() { if(ref == NULL) throw SRC_BUG; return ref->get_position(); };

    protected:
        S_I inherited_read(char *a, size_t size);
        S_I inherited_write(const char *a, size_t size);

    private:
        std::string key;
        U_32 len;
        generic_file *ref;
        unsigned char *buffer;
        size_t buf_size;
    };

} // end of namespace

#endif
