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

/*

 * Copyright (c) 2009 CTTC

 *

 * 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, Include., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 * Author: Nicola Baldo <nbaldo@cttc.es>

 */

#include <iomanip>

#include <cmath>

#include "ns3/log.h"

#include "radiotap-header.h"

NS_LOG_COMPONENT_DEFINE ("RadiotapHeader");

namespace ns3 {

NS_OBJECT_ENSURE_REGISTERED (RadiotapHeader);

RadiotapHeader::RadiotapHeader()

  : m_length (8),

    m_present (0),

    m_tsft (0),

    m_flags (FRAME_FLAG_NONE),

    m_rate (0),

    m_channelFreq (0),

    m_channelFlags (CHANNEL_FLAG_NONE),

    m_antennaSignal (0),

    m_antennaNoise (0)

{

  NS_LOG_FUNCTION (this);

}

TypeId RadiotapHeader::GetTypeId (void)

{

  static TypeId tid = TypeId ("ns3::RadiotapHeader")

    .SetParent<Header> ()

    .AddConstructor<RadiotapHeader> ()

  ;

  return tid;

}

TypeId 

RadiotapHeader::GetInstanceTypeId (void) const

{

  return GetTypeId ();

}

uint32_t

RadiotapHeader::GetSerializedSize (void) const

{

  NS_LOG_FUNCTION (this);

  return m_length;

}

void

RadiotapHeader::Serialize (Buffer::Iterator start) const

{

  NS_LOG_FUNCTION (this << &start);

  start.WriteU8 (0); // major version of radiotap header

  start.WriteU8 (0); // pad field

  start.WriteU16 (m_length); // entire length of radiotap data + header

  start.WriteU32 (m_present); // bits describing which fields follow header

  //

  // Time Synchronization Function Timer (when the first bit of the MPDU 

  // arrived at the MAC)

  //

  if (m_present & RADIOTAP_TSFT) // bit 0

    {

      start.WriteU64 (m_tsft);

    }

  //

  // Properties of transmitted and received frames.

  //

  if (m_present & RADIOTAP_FLAGS) // bit 1

    {

      start.WriteU8 (m_flags);

    }

  //

  // TX/RX data rate in units of 500 kbps

  //

  if (m_present & RADIOTAP_RATE) // bit 2

    {

      start.WriteU8 (m_rate);

    }

  //

  // Tx/Rx frequency in MHz, followed by flags.

  //

  if (m_present & RADIOTAP_CHANNEL) // bit 3

    {

      start.WriteU16 (m_channelFreq);

      start.WriteU16 (m_channelFlags);

    }

  //

  // RF signal power at the antenna, decibel difference from an arbitrary, fixed

  // reference.

  //

  if (m_present & RADIOTAP_DBM_ANTSIGNAL) // bit 5

    {

      start.WriteU8 (m_antennaSignal);

    }

  //

  // RF noise power at the antenna, decibel difference from an arbitrary, fixed 

  // reference.

  //

  if (m_present & RADIOTAP_DBM_ANTNOISE) // bit 6

    {

      start.WriteU8 (m_antennaNoise);

    }

}

uint32_t

RadiotapHeader::Deserialize (Buffer::Iterator start)

{

  NS_LOG_FUNCTION (this << &start);

  uint8_t tmp = start.ReadU8 (); // major version of radiotap header

  NS_ASSERT_MSG (tmp == 0x00, "RadiotapHeader::Deserialize(): Unexpected major version");

  start.ReadU8 (); // pad field

  m_length = start.ReadU16 (); // entire length of radiotap data + header

  m_present = start.ReadU32 (); // bits describing which fields follow header

  uint32_t bytesRead = 8;

  //

  // Time Synchronization Function Timer (when the first bit of the MPDU arrived at the MAC)

  //

  if (m_present & RADIOTAP_TSFT) // bit 0

    {

      m_tsft = start.ReadU64 ();

      bytesRead += 8;

    }

  //

  // Properties of transmitted and received frames.

  //

  if (m_present & RADIOTAP_FLAGS) // bit 1

    {

      m_flags = start.ReadU8 ();

      ++bytesRead;

    }

  //

  // TX/RX data rate in units of 500 kbps

  //

  if (m_present & RADIOTAP_RATE) // bit 2

    {

      m_rate = start.ReadU8 ();

      ++bytesRead;

    }

  //

  // Tx/Rx frequency in MHz, followed by flags.

  //

  if (m_present & RADIOTAP_CHANNEL) // bit 3

    {

      m_channelFreq = start.ReadU16 ();

      m_channelFlags = start.ReadU16 ();

      bytesRead += 4;

    }

  //

  // The hop set and pattern for frequency-hopping radios.  We don't need it but

  // still need to account for it.

  //

  if (m_present & RADIOTAP_FHSS) // bit 4

    {

      start.ReadU8 ();

      ++bytesRead;

    }

  //

  // RF signal power at the antenna, decibel difference from an arbitrary, fixed

  // reference.

  //

  if (m_present & RADIOTAP_DBM_ANTSIGNAL) // bit 5

    {

      m_antennaSignal = start.ReadU8 ();

      ++bytesRead;

    }

  //

  // RF noise power at the antenna, decibel difference from an arbitrary, fixed 

  // reference.

  //

  if (m_present & RADIOTAP_DBM_ANTNOISE) // bit 6

    {

      m_antennaNoise = start.ReadU8 ();

      ++bytesRead;

    }

  NS_ASSERT_MSG (m_length == bytesRead, "RadiotapHeader::Deserialize(): expected and actual lengths inconsistent");

  return bytesRead;

}

void

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

{

  NS_LOG_FUNCTION (this << &os);

  os << " tsft=" << m_tsft

     << " flags=" << std::hex << m_flags << std::dec

     << " rate=" << (uint16_t) m_rate

     << " freq=" << m_channelFreq

     << " chflags=" << std::hex << (uint32_t)m_channelFlags << std::dec

     << " signal=" << (int16_t) m_antennaSignal

     << " noise=" << (int16_t) m_antennaNoise;

}

void

RadiotapHeader::SetTsft (uint64_t value)

{

  NS_LOG_FUNCTION (this << value);

  m_tsft = value;

  if (!(m_present & RADIOTAP_TSFT))

    {

      m_present |= RADIOTAP_TSFT;

      m_length += 8;

    }

  NS_LOG_LOGIC (this << " m_length=" << m_length << " m_present=0x" << std::hex << m_present << std::dec);

}

uint64_t

RadiotapHeader::GetTsft () const

{

  NS_LOG_FUNCTION (this);

  return m_tsft;

}

void 

RadiotapHeader::SetFrameFlags (uint8_t flags)

{

  m_flags = flags;

  if (!(m_present & RADIOTAP_FLAGS))

    {

      m_present |= RADIOTAP_FLAGS;

      m_length += 1;

    }

  NS_LOG_LOGIC (this << " m_length=" << m_length << " m_present=0x" << std::hex << m_present << std::dec);

}

uint8_t

RadiotapHeader::GetFrameFlags (void) const

{

  NS_LOG_FUNCTION (this);

  return m_flags;

}

void 

RadiotapHeader::SetRate (uint8_t rate)

{

  m_rate = rate;

  if (!(m_present & RADIOTAP_RATE))

    {

      m_present |= RADIOTAP_RATE;

      m_length += 1;

    }

  NS_LOG_LOGIC (this << " m_length=" << m_length << " m_present=0x" << std::hex << m_present << std::dec);

}

uint8_t

RadiotapHeader::GetRate (void) const

{

  NS_LOG_FUNCTION (this);

  return m_rate;

}

void 

RadiotapHeader::SetChannelFrequencyAndFlags (uint16_t frequency, uint16_t flags)

{

  NS_LOG_FUNCTION (this << frequency << flags);

  m_channelFreq = frequency;

  m_channelFlags = flags;

  if (!(m_present & RADIOTAP_CHANNEL))

    {

      m_present |= RADIOTAP_CHANNEL;

      m_length += 4;

    }

  NS_LOG_LOGIC (this << " m_length=" << m_length << " m_present=0x" << std::hex << m_present << std::dec);

}

uint16_t 

RadiotapHeader::GetChannelFrequency (void) const

{

  NS_LOG_FUNCTION (this);

  return m_channelFreq;

}

uint16_t 

RadiotapHeader::GetChannelFlags (void) const

{

  NS_LOG_FUNCTION (this);

  return m_channelFlags;

}

void 

RadiotapHeader::SetAntennaSignalPower (double signal)

{

  NS_LOG_FUNCTION (this << signal);

  if (!(m_present & RADIOTAP_DBM_ANTSIGNAL))

    {

      m_present |= RADIOTAP_DBM_ANTSIGNAL;

      m_length += 1;

    }

  if (signal > 127)

    {

      m_antennaSignal = 127;

    }

  else if (signal < -128)

    {

      m_antennaSignal = -128;

    }

  else

    {

      m_antennaSignal = static_cast<int8_t> (floor (signal + 0.5));

    }

  NS_LOG_LOGIC (this << " m_length=" << m_length << " m_present=0x" << std::hex << m_present << std::dec);

}

uint8_t

RadiotapHeader::GetAntennaSignalPower (void) const

{

  NS_LOG_FUNCTION (this);

  return m_antennaSignal;

}

void

RadiotapHeader::SetAntennaNoisePower (double noise)

{

  NS_LOG_FUNCTION (this << noise);

  if (!(m_present & RADIOTAP_DBM_ANTNOISE))

    {

      m_present |= RADIOTAP_DBM_ANTNOISE;

      m_length += 1;

    }

  if (noise > 127.0)

    {

      m_antennaNoise = 127;

    }

  else if (noise < -128.0)

    {

      m_antennaNoise = -128;

    }

  else

    {

      m_antennaNoise = static_cast<int8_t> (floor (noise + 0.5));

    }

  NS_LOG_LOGIC (this << " m_length=" << m_length << " m_present=0x" << std::hex << m_present << std::dec);

}

uint8_t 

RadiotapHeader::GetAntennaNoisePower (void) const

{

  NS_LOG_FUNCTION (this);

  return m_antennaNoise;

}

} // namespace ns3