/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2005,2006 INRIA

 *

 * 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>

 */

#include "packet.h"

#include "ns3/assert.h"

#include "ns3/log.h"

NS_LOG_COMPONENT_DEFINE ("Packet");

namespace ns3 {

uint32_t Packet::m_globalUid = 0;

TypeId 

TagIterator::Item::GetTypeId (void) const

{

  return m_tid;

}

uint32_t 

TagIterator::Item::GetStart (void) const

{

  return m_start;

}

uint32_t 

TagIterator::Item::GetEnd (void) const

{

  return m_end;

}

void 

TagIterator::Item::GetTag (Tag &tag) const

{

  if (tag.GetInstanceTypeId () != GetTypeId ())

    {

      NS_FATAL_ERROR ("The tag you provided is not of the right type.");

    }

  tag.Deserialize (m_buffer);

}

TagIterator::Item::Item (TypeId tid, uint32_t start, uint32_t end, TagBuffer buffer)

  : m_tid (tid),

    m_start (start),

    m_end (end),

    m_buffer (buffer)

{}

bool 

TagIterator::HasNext (void) const

{

  return m_current.HasNext ();

}

TagIterator::Item 

TagIterator::Next (void)

{

  TagList::Iterator::Item i = m_current.Next ();

  return TagIterator::Item (i.tid, 

                            i.start-m_current.GetOffsetStart (), 

                            i.end-m_current.GetOffsetStart (), 

                            i.buf);

}

TagIterator::TagIterator (TagList::Iterator i)

  : m_current (i)

{}

void 

Packet::Ref (void) const

{

  m_refCount++;

}

void 

Packet::Unref (void) const

{

  m_refCount--;

  if (m_refCount == 0)

    {

      delete this;

    }

}

Ptr<Packet> 

Packet::Copy (void) const

{

  // we need to invoke the copy constructor directly

  // rather than calling Create because the copy constructor

  // is private.

  return Ptr<Packet> (new Packet (*this), false);

}

Packet::Packet ()

  : m_buffer (),

    m_tagList (),

    m_metadata (m_globalUid, 0),

    m_refCount (1)

{

  m_globalUid++;

}

Packet::Packet (const Packet &o)

  : m_buffer (o.m_buffer),

    m_tagList (o.m_tagList),

    m_metadata (o.m_metadata),

    m_refCount (1)

{}

Packet &

Packet::operator = (const Packet &o)

{

  if (this == &o)

    {

      return *this;

    }

  m_buffer = o.m_buffer;

  m_tagList = o.m_tagList;

  m_metadata = o.m_metadata;

  return *this;

}

Packet::Packet (uint32_t size)

  : m_buffer (size),

    m_tagList (),

    m_metadata (m_globalUid, size),

    m_refCount (1)

{

  m_globalUid++;

}

Packet::Packet (uint8_t const*buffer, uint32_t size)

  : m_buffer (),

    m_tagList (),

    m_metadata (m_globalUid, size),

    m_refCount (1)

{

  m_globalUid++;

  m_buffer.AddAtStart (size);

  Buffer::Iterator i = m_buffer.Begin ();

  i.Write (buffer, size);

}

Packet::Packet (const Buffer &buffer,  const TagList &tagList, const PacketMetadata &metadata)

  : m_buffer (buffer),

    m_tagList (tagList),

    m_metadata (metadata),

    m_refCount (1)

{}

Ptr<Packet>

Packet::CreateFragment (uint32_t start, uint32_t length) const

{

  NS_LOG_FUNCTION (this << start << length);

  Buffer buffer = m_buffer.CreateFragment (start, length);

  NS_ASSERT (m_buffer.GetSize () >= start + length);

  uint32_t end = m_buffer.GetSize () - (start + length);

  PacketMetadata metadata = m_metadata.CreateFragment (start, end);

  // again, call the constructor directly rather than

  // through Create because it is private.

  return Ptr<Packet> (new Packet (buffer, m_tagList, metadata), false);

}

uint32_t 

Packet::GetSize (void) const

{

  return m_buffer.GetSize ();

}

void

Packet::AddHeader (const Header &header)

{

  NS_LOG_FUNCTION (this << &header);

  uint32_t size = header.GetSerializedSize ();

  uint32_t orgStart = m_buffer.GetCurrentStartOffset ();

  bool resized = m_buffer.AddAtStart (size);

  if (resized)

    {

      m_tagList.AddAtStart (m_buffer.GetCurrentStartOffset () - orgStart,

                            m_buffer.GetCurrentStartOffset () + size);

    }

  header.Serialize (m_buffer.Begin ());

  m_metadata.AddHeader (header, size);

}

uint32_t

Packet::RemoveHeader (Header &header)

{

  NS_LOG_FUNCTION (this << &header);

  uint32_t deserialized = header.Deserialize (m_buffer.Begin ());

  m_buffer.RemoveAtStart (deserialized);

  m_metadata.RemoveHeader (header, deserialized);

  return deserialized;

}

void

Packet::AddTrailer (const Trailer &trailer)

{

  NS_LOG_FUNCTION (this << &trailer);

  uint32_t size = trailer.GetSerializedSize ();

  uint32_t orgEnd = m_buffer.GetCurrentEndOffset ();

  bool resized = m_buffer.AddAtEnd (size);

  if (resized)

    {

      m_tagList.AddAtEnd (m_buffer.GetCurrentEndOffset () - orgEnd,

                          m_buffer.GetCurrentEndOffset () - size);

    }

  Buffer::Iterator end = m_buffer.End ();

  trailer.Serialize (end);

  m_metadata.AddTrailer (trailer, size);

}

uint32_t

Packet::RemoveTrailer (Trailer &trailer)

{

  NS_LOG_FUNCTION (this << &trailer);

  uint32_t deserialized = trailer.Deserialize (m_buffer.End ());

  m_buffer.RemoveAtEnd (deserialized);

  m_metadata.RemoveTrailer (trailer, deserialized);

  return deserialized;

}

void 

Packet::AddAtEnd (Ptr<const Packet> packet)

{

  NS_LOG_FUNCTION (this << packet);

  uint32_t aStart = m_buffer.GetCurrentStartOffset ();

  uint32_t bEnd = packet->m_buffer.GetCurrentEndOffset ();

  m_buffer.AddAtEnd (packet->m_buffer);

  uint32_t appendPrependOffset = m_buffer.GetCurrentEndOffset () - packet->m_buffer.GetSize ();

  m_tagList.AddAtEnd (m_buffer.GetCurrentStartOffset () - aStart, 

                      appendPrependOffset);

  TagList copy = packet->m_tagList;

  copy.AddAtStart (m_buffer.GetCurrentEndOffset () - bEnd,

                   appendPrependOffset);

  m_tagList.Add (copy);

  m_metadata.AddAtEnd (packet->m_metadata);

}

void

Packet::AddPaddingAtEnd (uint32_t size)

{

  NS_LOG_FUNCTION (this << size);

  uint32_t orgEnd = m_buffer.GetCurrentEndOffset ();

  bool resized = m_buffer.AddAtEnd (size);

  if (resized)

    {

      m_tagList.AddAtEnd (m_buffer.GetCurrentEndOffset () - orgEnd,

                          m_buffer.GetCurrentEndOffset () - size);

    }

  m_metadata.AddPaddingAtEnd (size);

}

void 

Packet::RemoveAtEnd (uint32_t size)

{

  NS_LOG_FUNCTION (this << size);

  m_buffer.RemoveAtEnd (size);

  m_metadata.RemoveAtEnd (size);

}

void 

Packet::RemoveAtStart (uint32_t size)

{

  NS_LOG_FUNCTION (this << size);

  m_buffer.RemoveAtStart (size);

  m_metadata.RemoveAtStart (size);

}

void 

Packet::RemoveAllTags (void)

{

  NS_LOG_FUNCTION (this);

  m_tagList.RemoveAll ();

}

uint8_t const *

Packet::PeekData (void) const

{

  return m_buffer.PeekData ();

}

uint32_t 

Packet::GetUid (void) const

{

  return m_metadata.GetUid ();

}

void 

Packet::PrintTags (std::ostream &os) const

{

}

void 

Packet::Print (std::ostream &os) const

{

  PacketMetadata::ItemIterator i = m_metadata.BeginItem (m_buffer);

  while (i.HasNext ())

    {

      PacketMetadata::Item item = i.Next ();

      if (item.isFragment)

        {

          switch (item.type) {

          case PacketMetadata::Item::PAYLOAD:

            os << "Payload";

            break;

          case PacketMetadata::Item::HEADER:

          case PacketMetadata::Item::TRAILER:

            os << item.tid.GetName ();

            break;

          }

          os << " Fragment [" << item.currentTrimedFromStart<<":"

             << (item.currentTrimedFromStart + item.currentSize) << "]";

        }

      else

        {

          switch (item.type) {

          case PacketMetadata::Item::PAYLOAD:

            os << "Payload (size=" << item.currentSize << ")";

            break;

          case PacketMetadata::Item::HEADER:

          case PacketMetadata::Item::TRAILER:

            os << item.tid.GetName () << " (";

            {

              NS_ASSERT (item.tid.HasConstructor ());

              Callback<ObjectBase *> constructor = item.tid.GetConstructor ();

              NS_ASSERT (!constructor.IsNull ());

              ObjectBase *instance = constructor ();

              NS_ASSERT (instance != 0);

              Chunk *chunk = dynamic_cast<Chunk *> (instance);

              NS_ASSERT (chunk != 0);

              chunk->Deserialize (item.current);

              chunk->Print (os);

              delete chunk;

            }

            os << ")";

            break;

          }          

        }

      if (i.HasNext ())

        {

          os << " ";

        }

    }

#if 0

  // The code below will work only if headers and trailers

  // define the right attributes which is not the case for

  // now. So, as a temporary measure, we use the 

  // headers' and trailers' Print method as shown above.

  PacketMetadata::ItemIterator i = m_metadata.BeginItem (m_buffer);

  while (i.HasNext ())

    {

      PacketMetadata::Item item = i.Next ();

      if (item.isFragment)

        {

          switch (item.type) {

          case PacketMetadata::Item::PAYLOAD:

            os << "Payload";

            break;

          case PacketMetadata::Item::HEADER:

          case PacketMetadata::Item::TRAILER:

            os << item.tid.GetName ();

            break;

          }

          os << " Fragment [" << item.currentTrimedFromStart<<":"

             << (item.currentTrimedFromStart + item.currentSize) << "]";

        }

      else

        {

          switch (item.type) {

          case PacketMetadata::Item::PAYLOAD:

            os << "Payload (size=" << item.currentSize << ")";

            break;

          case PacketMetadata::Item::HEADER:

          case PacketMetadata::Item::TRAILER:

            os << item.tid.GetName () << "(";

            {

              NS_ASSERT (item.tid.HasConstructor ());

              Callback<ObjectBase *> constructor = item.tid.GetConstructor ();

              NS_ASSERT (constructor.IsNull ());

              ObjectBase *instance = constructor ();

              NS_ASSERT (instance != 0);

              Chunk *chunk = dynamic_cast<Chunk *> (instance);

              NS_ASSERT (chunk != 0);

              chunk->Deserialize (item.current);

              for (uint32_t j = 0; j < item.tid.GetAttributeN (); j++)

                {

                  std::string attrName = item.tid.GetAttributeName (j);

                  std::string value;

                  bool ok = chunk->GetAttribute (attrName, value);

                  NS_ASSERT (ok);

                  os << attrName << "=" << value;

                  if ((j + 1) < item.tid.GetAttributeN ())

                    {

                      os << ",";

                    }

                }

            }

            os << ")";

            break;

          }          

        }

      if (i.HasNext ())

        {

          os << " ";

        }

    }

#endif   

}

PacketMetadata::ItemIterator 

Packet::BeginItem (void) const

{

  return m_metadata.BeginItem (m_buffer);

}

void

Packet::EnableMetadata (void)

{

  NS_LOG_FUNCTION_NOARGS ();

  PacketMetadata::Enable ();

}

Buffer 

Packet::Serialize (void) const

{

  NS_LOG_FUNCTION (this);

  Buffer buffer;

  uint32_t reserve;

  // write metadata

  reserve = m_metadata.GetSerializedSize ();

  buffer.AddAtStart (reserve);

  m_metadata.Serialize (buffer.Begin (), reserve);

  // write tags

  //XXX

  //reserve = m_tags.GetSerializedSize ();

  //buffer.AddAtStart (reserve);

  //m_tags.Serialize (buffer.Begin (), reserve);

  // aggregate byte buffer, metadata, and tags

  Buffer tmp = m_buffer.CreateFullCopy ();

  tmp.AddAtEnd (buffer);

  // write byte buffer size.

  tmp.AddAtStart (4);

  tmp.Begin ().WriteU32 (m_buffer.GetSize ());

  return tmp;

}

void 

Packet::Deserialize (Buffer buffer)

{

  NS_LOG_FUNCTION (this);

  Buffer buf = buffer;

  // read size

  uint32_t packetSize = buf.Begin ().ReadU32 ();

  buf.RemoveAtStart (4);

  // read buffer.

  buf.RemoveAtEnd (buf.GetSize () - packetSize);