/* -----------------------------------------------------------------------------

The copyright in this software is being made available under the Clear BSD

License, included below. No patent rights, trademark rights and/or 

other Intellectual Property Rights other than the copyrights concerning 

the Software are granted under this license.

The Clear BSD License

Copyright (c) 2018-2026, Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. & The VVdeC Authors.

All rights reserved.

Redistribution and use in source and binary forms, with or without modification,

are permitted (subject to the limitations in the disclaimer below) provided that

the following conditions are met:

     * Redistributions of source code must retain the above copyright notice,

     this list of conditions and the following disclaimer.

     * Redistributions in binary form must reproduce the above copyright

     notice, this list of conditions and the following disclaimer in the

     documentation and/or other materials provided with the distribution.

     * Neither the name of the copyright holder nor the names of its

     contributors may be used to endorse or promote products derived from this

     software without specific prior written permission.

NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED BY

THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND

CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR

CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR

BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER

IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

POSSIBILITY OF SUCH DAMAGE.

------------------------------------------------------------------------------------------- */

/**

 \file     NALread.cpp

 \brief    reading functionality for NAL units

 */

#include <vector>

#include <algorithm>

#include <ostream>

#include "NALread.h"

#include "CommonLib/NAL.h"

#include "CommonLib/BitStream.h"

#include "CommonLib/Rom.h"

#include "CommonLib/dtrace_next.h"

namespace vvdec

{

//! \ingroup DecoderLib

//! \{

#if ENABLE_TRACING

static void xTraceNalUnitHeader(InputNALUnit& nalu)

{

  DTRACE( g_trace_ctx, D_NALUNITHEADER, "*********** NAL UNIT (%s) ***********\n", nalUnitTypeToString(nalu.m_nalUnitType) );

  bool zeroTidRequiredFlag = 0;

  if((nalu.m_nalUnitType >= 16) && (nalu.m_nalUnitType <= 31)) {

    zeroTidRequiredFlag = 1;

  }

  DTRACE( g_trace_ctx, D_NALUNITHEADER, "%-50s u(%d)  : %u\n", "zero_tid_required_flag", 1, zeroTidRequiredFlag );

  DTRACE( g_trace_ctx, D_NALUNITHEADER, "%-50s u(%d)  : %u\n", "nuh_temporal_id_plus1", 3, nalu.m_temporalId + 1 );

  DTRACE( g_trace_ctx, D_NALUNITHEADER, "%-50s u(%d)  : %u\n", "nal_unit_type_lsb", 4, (nalu.m_nalUnitType) - (zeroTidRequiredFlag << 4));

  DTRACE( g_trace_ctx, D_NALUNITHEADER, "%-50s u(%d)  : %u\n", "nuh_layer_id_plus1", 7, nalu.m_nuhLayerId+1);

  DTRACE( g_trace_ctx, D_NALUNITHEADER, "%-50s u(%d)  : %u\n", "nuh_reserved_zero_bit", 1, 0 );

}

#endif

void InputNALUnit::readNalUnitHeader()

{

  InputNALUnit&   nalu = *this;

  InputBitstream& bs   = nalu.getBitstream();

  nalu.m_forbiddenZeroBit   = bs.read(1);                 // forbidden zero bit

  nalu.m_nuhReservedZeroBit = bs.read(1);                 // nuh_reserved_zero_bit

  nalu.m_nuhLayerId         = bs.read(6);                 // nuh_layer_id

  CHECK( nalu.m_nuhLayerId < 0, "this needs to be adjusted for the reco yuv output" );

  CHECK( nalu.m_nuhLayerId > 55, "The value of nuh_layer_id shall be in the range of 0 to 55, inclusive" );

  nalu.m_nalUnitType        = (NalUnitType) bs.read(5);   // nal_unit_type

  nalu.m_temporalId         = bs.read(3) - 1;             // nuh_temporal_id_plus1

#if ENABLE_TRACING

  xTraceNalUnitHeader(nalu);

#endif

  // only check these rules for base layer

  if (nalu.m_nuhLayerId == 0)

  {

    if ( nalu.m_temporalId )

    {

    }

    else

    {

      CHECK( nalu.m_nalUnitType == NAL_UNIT_CODED_SLICE_STSA, "When NAL unit type is equal to STSA_NUT, TemporalId shall not be equal to 0" );

    }

  }

}

}