//
// aegis - project change supervisor
// Copyright (C) 2006, 2008, 2011, 2012 Peter Miller
//
// 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 3 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, see <http://www.gnu.org/licenses/>.
//

#ifndef LIBAEGIS_OUTPUT_BZIP2_H
#define LIBAEGIS_OUTPUT_BZIP2_H

#include <common/ac/bzlib.h>

#include <libaegis/output/filter.h>

/**
  * The output_filter_bzip2 class is used to represent an output filter which
  * compresses the data before writing it to the deeper output stream.
  */
class output_filter_bzip2:
    public output_filter
{
public:
    /**
      * The destructor.
      */
    virtual ~output_filter_bzip2();

    /**
      * The create class method is used to create new dynamically
      * allocated instances of this class.
      *
      * @param deeper
      *     the output stream this filter will write its output to.
      */
    static pointer create(const output::pointer &deeper);

protected:
    // See base class for documentation.
    long ftell_inner(void) const;

    // See base class for documentation.
    void write_inner(const void *data, size_t length);

    // See base class for documentation.
    nstring type_name(void) const;

    // See base class for documentation.
    void end_of_line_inner(void);

private:
    /**
      * The constructor.  It is private on purpose, use the #create
      * class method instead.
      *
      * @param deeper
      *     the output stream this filter will write its output to.
      */
    output_filter_bzip2(const output::pointer &deeper);

    /**
      * The stream instance variable is used to remember somthign that
      * the bzip2 code wants to remember.  It is opaque to us.
      */
    bz_stream stream;

    enum { BUFFER_SIZE = 1 << 14 };

    /**
      * The buf instance variable is used to remember the buffered
      * output data.
      */
    char *buf;

    /**
      * The pos instance variable is used to remember the current output
      * position.
      */
    long pos;

    /**
      * The bol instance variable is used to remember whether or not the
      * output is positioned at the beginning of a lone.
      */
    bool bol;

    /**
      * The bzlib_fatal_error method is used to report a fatal error
      * from the bzip2 engine.
      */
    void bzlib_fatal_error(int err);

    /**
      * The default constructor.  Do not use.
      */
    output_filter_bzip2();

    /**
      * The copy constructor.  Do not use.
      */
    output_filter_bzip2(const output_filter_bzip2 &);

    /**
      * The assignment operator.  Do not use.
      */
    output_filter_bzip2 &operator=(const output_filter_bzip2 &);
};

#endif // LIBAEGIS_OUTPUT_BZIP2_H
// vim: set ts=8 sw=4 et :