DataBlockComposite.h

#ifndef MANTID_DATAHANDLING_DATABLOCK_COMPOSITE_H_
#define MANTID_DATAHANDLING_DATABLOCK_COMPOSITE_H_

#include "MantidDataHandling/DataBlock.h"
#include "MantidDataHandling/DllConfig.h"

namespace Mantid {
namespace DataHandling {

  /** DataBlockComposite: The DataBlockComposite handles a collection
      of DataBlocks. It represents a set of contiguous spectrum numbers
      which are to be consumed elsewhere.

  Copyright © 2016 ISIS Rutherford Appleton Laboratory, NScD Oak Ridge
  National Laboratory & European Spallation Source

  This file is part of Mantid.

  Mantid is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 3 of the License, or
  (at your option) any later version.

  Mantid 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, see <http://www.gnu.org/licenses/>.

  File change history is stored at:
  <https://github.com/mantidproject/mantid>
  Code Documentation is available at: <http://doxygen.mantidproject.org>
  */
class DLLExport DataBlockComposite : public DataBlock {
public:
  int64_t getMinSpectrumID() const override;
  void setMinSpectrumID(int64_t) override;

  int64_t getMaxSpectrumID() const override;
  void setMaxSpectrumID(int64_t) override;

  size_t getNumberOfSpectra() const override;
  size_t getNumberOfChannels() const override;
  int getNumberOfPeriods() const override;

  std::unique_ptr<DataBlockGenerator> getGenerator() const override;

  bool operator==(const DataBlockComposite &other) const;

  // DataBlockComposite only mehtods
  void addDataBlock(DataBlock dataBlock);
  std::vector<DataBlock> getDataBlocks();
  DataBlockComposite operator+(const DataBlockComposite &other);
  void removeSpectra(DataBlockComposite &toRemove);
  void truncate(int64_t specMin, int64_t specMax);

private:
  std::vector<DataBlock> m_dataBlocks;
};

/**
* Populates a DataBlockComposite with DataBlocks which are extracted from a
* indexable collection (array-type). Note that std::is_array does not
* work on boost::shared_array which is one of the use cases. Hence this
* function could get abused.
* @param dataBlockComposite: the detector block composite which will get
* populated
* @param indexContainer: the container of indices
* @param nArray: the number of array elements
* @param numberOfPeriods: the number of periods
* @param numberOfChannels: the number of channels
*/
template <typename T>
void DLLExport
populateDataBlockCompositeWithContainer(DataBlockComposite &dataBlockComposite,
                                        T &indexContainer, int64_t nArray,
                                        int numberOfPeriods,
                                        size_t numberOfChannels) {

  // Find all intervals among the index array (this assumes that spectrum index
  // increases monotonically, else we would have to sort first)
  int64_t startValue = indexContainer[0];
  int64_t previousValue = startValue;

  for (int64_t arrayIndex = 1; arrayIndex < nArray; ++arrayIndex) {
    auto isSequential = (indexContainer[arrayIndex] - previousValue) == 1;
    if (!isSequential) {
      // We must have completed an interval, we create a DataBlock and add it
      auto numberOfSpectra = previousValue - startValue + 1;
      DataBlock dataBlock(numberOfPeriods, numberOfSpectra, numberOfChannels);
      dataBlock.setMinSpectrumID(startValue);
      dataBlock.setMaxSpectrumID(previousValue);
      dataBlockComposite.addDataBlock(dataBlock);

      // Now reset the startValue to the beginning of the new index
      startValue = indexContainer[arrayIndex];
    }

    // Set the previous value to the current value;
    previousValue = indexContainer[arrayIndex];
  }

  // The last interval would not have been added
  auto numberOfSpectra = previousValue - startValue + 1;
  DataBlock dataBlock(numberOfPeriods, numberOfSpectra, numberOfChannels);
  dataBlock.setMinSpectrumID(startValue);
  dataBlock.setMaxSpectrumID(previousValue);
  dataBlockComposite.addDataBlock(dataBlock);
}

}
}
#endif