/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2013, Regents of the University of California
 *                     Alexander Afanasyev
 *                     Zhenkai Zhu
 *
 * BSD license, See the LICENSE file for more information
 *
 * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
 *         Alexander Afanasyev <alexander.afanasyev@ucla.edu>
 */

#ifndef NDN_NDN_CHARBUF_H
#define NDN_NDN_CHARBUF_H

#include "ndn.cxx/common.h"
#include <boost/shared_ptr.hpp>
#include <boost/iostreams/detail/ios.hpp>
#include <boost/iostreams/categories.hpp>
#include <boost/iostreams/stream.hpp>

namespace ndn {

class Charbuf;
typedef boost::shared_ptr<Charbuf> CharbufPtr;

//  This class is mostly used in Wrapper; users should not be directly using this class
// The main purpose of this class to is avoid manually create and destroy charbuf everytime
class Charbuf
{
public:
  Charbuf();
  Charbuf(ccn_charbuf *buf);
  Charbuf(const Charbuf &other);
  Charbuf(const void *buf, size_t length);
  ~Charbuf();

  // expose internal data structure, use with caution!!
  ccn_charbuf *
  getBuf() { return m_buf; }

  const ccn_charbuf *
  getBuf() const { return m_buf; }

  const unsigned char *
  buf () const
  { return m_buf->buf; }

  size_t
  length () const
  { return m_buf->length; }

private:
  void init(ccn_charbuf *buf);

protected:
  ccn_charbuf *m_buf;
};

namespace iostreams
{

class charbuf_append_device {
public:
  typedef char  char_type;
  typedef boost::iostreams::sink_tag       category;
  
  charbuf_append_device (Charbuf& cnt);
  
  std::streamsize
  write(const char_type* s, std::streamsize n);
protected:
  Charbuf& container;
};

} // iostreams

struct charbuf_stream : public boost::iostreams::stream<iostreams::charbuf_append_device>
{
  charbuf_stream ()
    : m_device (m_buf)
  {
    open (m_device);
  }

  Charbuf &
  buf ()
  {
    flush ();
    return m_buf;
  }

private:
  Charbuf m_buf;
  iostreams::charbuf_append_device m_device;
};

} // ndn

#endif // NDN_NDN_CHARBUF_H