/**
 * Stone of Orthanc
 * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
 * Department, University Hospital of Liege, Belgium
 * Copyright (C) 2017-2023 Osimis S.A., Belgium
 * Copyright (C) 2021-2025 Sebastien Jodogne, ICTEAM UCLouvain, Belgium
 *
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program. If not, see
 * <http://www.gnu.org/licenses/>.
 **/


#include "ParsedDicomDataset.h"

#include <Logging.h>
#include <DicomParsing/FromDcmtkBridge.h>


namespace OrthancStone
{
  static DcmItem* LookupPath(Orthanc::ParsedDicomFile& dicom,
                             const Orthanc::DicomPath& path)
  {
    DcmItem* node = dicom.GetDcmtkObject().getDataset();

    for (size_t i = 0; i < path.GetPrefixLength(); i++)
    {
      const Orthanc::DicomTag& tmp = path.GetPrefixTag(i);
      DcmTagKey tag(tmp.GetGroup(), tmp.GetElement());

      DcmSequenceOfItems* sequence = NULL;
      if (!node->findAndGetSequence(tag, sequence).good() ||
          sequence == NULL)
      {
        return NULL;
      }

      unsigned long pos = path.GetPrefixIndex(i);
      if (pos >= sequence->card())
      {
        return NULL;
      }

      node = sequence->getItem(pos);
      if (node == NULL)
      {
        return NULL;
      }
    }

    return node;
  }

    
  bool ParsedDicomDataset::GetStringValue(std::string& result,
                                          const Orthanc::DicomPath& path) const
  {
    DcmItem* node = LookupPath(dicom_, path);
      
    if (node != NULL)
    {
      DcmTagKey tag(path.GetFinalTag().GetGroup(), path.GetFinalTag().GetElement());

      DcmElement* element = NULL;
      if (node->findAndGetElement(tag, element).good() &&
          element != NULL)
      {
        // Leverage the Orthanc framework to convert any VR as a string
        const Orthanc::ValueRepresentation vr = Orthanc::FromDcmtkBridge::LookupValueRepresentation(path.GetFinalTag());
        const std::set<Orthanc::DicomTag> ignoreTagLength;
        std::unique_ptr<Orthanc::DicomValue> value(
          Orthanc::FromDcmtkBridge::ConvertLeafElement(
            *element, Orthanc::DicomToJsonFlags_None, 0, Orthanc::Encoding_Ascii, false, ignoreTagLength, vr));
        return value->CopyToString(result, false /* no binary */);
      }
    }

    return false;
  }


  bool ParsedDicomDataset::GetSequenceSize(size_t& size,
                                           const Orthanc::DicomPath& path) const
  {
    DcmItem* node = LookupPath(dicom_, path);
      
    if (node != NULL)
    {
      DcmTagKey tag(path.GetFinalTag().GetGroup(), path.GetFinalTag().GetElement());

      DcmSequenceOfItems* s = NULL;
      if (node->findAndGetSequence(tag, s).good() &&
          s != NULL)
      {
        size = s->card();
        return true;
      }
    }

    return false;
  }
}