/* -*-    Mode:C++; c-basic-offset:4; tab-width:4; indent-tabs-mode:f -*- */

/*

 * Copyright (c) 2005 INRIA

 * All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * 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

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 */

#ifndef CHUNK_H

#define CHUNK_H

#include <stdint.h>

#include <ostream>

#include "buffer.h"

namespace ns3 {

/**

 * \brief Protocol header serialization and deserialization.

 *

 * Every Protocol header which needs to be inserted and removed

 * from a Packet instance must derive from this abstract base class

 */

class Chunk {

public:

    Chunk ();

    /**

     * Derived classes must provided an explicit virtual destructor

     */

    virtual ~Chunk () = 0;

    void print (std::ostream &os) const;

    void add (Buffer *buffer) const;

    void peek (Buffer const *buffer);

    void remove (Buffer *buffer);

private:

    bool m_mustPeekBeforeRemove;

    /**

     * \param os the std output stream in which this 

     *       protocol header must print itself.

     */

    virtual void print (std::ostream *os) const = 0;

    /**

     * \param buffer the buffer in which the protocol header

     *    must serialize itself.

     *

     * This method must:

     *   - reserve room for its serialized representation in the input buffer

     *   - serialize itself in this reserved room

     */

    virtual void addTo (Buffer *buffer) const = 0;

    /**

     * \param buffer the buffer from which the protocol header must

     *    deserialize itself.

     *

     */

    virtual void peekFrom (Buffer const *buffer) = 0;

    /**

     * \param buffer the buffer from which the protocol header

     *    must remove itself.

     *

     * This method must remove its serialized representation 

     * from the input buffer. This method does not need to deserialize

     * the data itself.

     */

    virtual void removeFrom (Buffer *buffer) = 0;

};

std::ostream& operator<< (std::ostream& os, Chunk const& chunk);

}; // namespace ns3

#endif /* CHUNK_H */