/*!
   \file domain_algorithm_transformation.hpp
   \author Ha NGUYEN
   \since 02 Jul 2015
   \date 02 Jul 2015

   \brief Interface for all domain transformation algorithms.
 */

#include "domain_algorithm_transformation.hpp"

namespace xios {

CDomainAlgorithmTransformation::CDomainAlgorithmTransformation(CDomain* domainDestination, CDomain* domainSource)
 : CGenericAlgorithmTransformation(), domainDest_(domainDestination), domainSrc_(domainSource)
{
}

CDomainAlgorithmTransformation::~CDomainAlgorithmTransformation()
{
}

void CDomainAlgorithmTransformation::computeIndexSourceMapping_(const std::vector<CArray<double,1>* >& dataAuxInputs)
{
}

/*!
  Compute an array of global index from a global index on a domain
  \param[in] domainDestGlobalIndex global index on an domain of destination grid
  \param[in] domainSrcGlobalIndex global index on an domain of source grid (which are needed by one index on domain destination)
  \param[in] domainPositionInGrid position of the domain in the grid
  \param[in] gridDestGlobalDim dimension size of destination grid (it should share the same size for all dimension, maybe except the domain on which transformation is performed)
  \param[in] gridSrcGlobalDim dimension size of source grid (it should share the same size for all dimension, maybe except the domain on which transformation is performed)
  \param[in] globalIndexGridDestSendToServer global index of destination grid which are to be sent to server(s), this array is already acsending sorted
  \param[in/out] globalIndexDestGrid array of global index (for 2d grid, this array is a line, for 3d, this array represents a plan). It should be preallocated
  \param[in/out] globalIndexSrcGrid array of global index of source grid (for 2d grid, this array is a line, for 3d, this array represents a plan). It should be preallocated
*/
void CDomainAlgorithmTransformation::computeGlobalGridIndexFromGlobalIndexElement(int domainDestGlobalIndex,
                                                                          const std::vector<int>& domainSrcGlobalIndex,
                                                                          const std::vector<int>& destGlobalIndexPositionInGrid,
                                                                          int domainPositionInGrid,
                                                                          const std::vector<int>& gridDestGlobalDim,
                                                                          const std::vector<int>& gridSrcGlobalDim,
                                                                          const std::vector<size_t>& globalIndexGridDestSendToServer,
                                                                          CArray<size_t,1>& globalIndexDestGrid,
                                                                          std::vector<std::vector<size_t> >& globalIndexSrcGrid)
{
  int globalDim = gridDestGlobalDim.size();
  int numElement = globalDim - 1;
  int domainElementPosition = 0;
  std::vector<int> currentIndex(globalDim);
  std::vector<int> gridDomainGlobalDim(numElement), indexMap(numElement);
  std::vector<int> idxLoop(numElement, 0), domainSrcGlobalDim(2), domainDestGlobalDim(2);


  size_t ssize = 1, idx = 0, realGlobalIndexSize = 0;
  for (int i = 0; i< globalDim; ++i)
  {
    if (domainPositionInGrid == i) continue;
    if (domainPositionInGrid == (i+1))
    {
      domainDestGlobalDim[0] = gridDestGlobalDim[i];
      domainDestGlobalDim[1] = gridDestGlobalDim[i+1];
      domainSrcGlobalDim[0] = gridSrcGlobalDim[i];
      domainSrcGlobalDim[1] = gridSrcGlobalDim[i+1];
      gridDomainGlobalDim[idx] = 1;
      domainElementPosition = idx;
    }
    else
    {
      gridDomainGlobalDim[idx] = gridDestGlobalDim[i];
    }
    indexMap[idx] = i;
    ++idx;
  }
  int iIndex = domainDestGlobalIndex % domainDestGlobalDim[0];
  int jIndex = domainDestGlobalIndex / domainDestGlobalDim[0];

  for (int i = 0; i< numElement; ++i) ssize *= gridDomainGlobalDim[i];

  std::vector<size_t>::const_iterator itbArr = globalIndexGridDestSendToServer.begin(), itArr,
                                      iteArr = globalIndexGridDestSendToServer.end();
  idx = 0;
  while (idx < ssize)
  {
    for (int i = 0; i < numElement; ++i)
    {
      if (idxLoop[i] == gridDomainGlobalDim[i])
      {
        idxLoop[i] = 0;
        ++idxLoop[i+1];
      }
    }

    for (int i = 0; i < numElement; ++i)
    {
      if (domainElementPosition == i)
      {
        currentIndex[indexMap[i]]   = iIndex;
        currentIndex[indexMap[i]+1] = jIndex;
      }
      else
        currentIndex[indexMap[i]] = idxLoop[i];
    }

    size_t globIndex = currentIndex[0];
    size_t mulDim = 1;
    for (int k = 1; k < globalDim; ++k)
    {
      mulDim *= gridDestGlobalDim[k-1];
      globIndex += (currentIndex[k])*mulDim;
    }

    if (std::binary_search(itbArr, iteArr, globIndex)) ++realGlobalIndexSize;
    ++idxLoop[0];
    ++idx;
  }

  if (globalIndexDestGrid.numElements() != realGlobalIndexSize)
    globalIndexDestGrid.resize(realGlobalIndexSize);

  if (realGlobalIndexSize != globalIndexSrcGrid.size()) globalIndexSrcGrid.resize(realGlobalIndexSize);
  for (int i = 0; i < globalIndexSrcGrid.size(); ++i)
    if (globalIndexSrcGrid[i].size() != domainSrcGlobalIndex.size())
      globalIndexSrcGrid[i].resize(domainSrcGlobalIndex.size());

  size_t realGlobalIndex = 0;
  idx = 0;
  idxLoop.assign(globalDim, 0);
  while (idx < ssize)
  {
    for (int i = 0; i < numElement; ++i)
    {
      if (idxLoop[i] == gridDomainGlobalDim[i])
      {
        idxLoop[i] = 0;
        ++idxLoop[i+1];
      }
    }

    for (int i = 0; i < numElement; ++i)
    {
      if (domainElementPosition == i)
      {
        currentIndex[indexMap[i]]   = iIndex;
        currentIndex[indexMap[i]+1] = jIndex;
      }
      else
        currentIndex[indexMap[i]] = idxLoop[i];
    }

    size_t globIndex = currentIndex[0];
    size_t mulDim = 1;
    for (int k = 1; k < globalDim; ++k)
    {
      mulDim *= gridDestGlobalDim[k-1];
      globIndex += (currentIndex[k])*mulDim;
    }

    if (std::binary_search(itbArr, iteArr, globIndex))
    {
      globalIndexDestGrid(realGlobalIndex) = globIndex;
      for (int i = 0; i < globalIndexSrcGrid[realGlobalIndex].size(); ++i)
      {
        domainGlobalIndex(domainSrcGlobalIndex[i], domainSrcGlobalDim[0], domainSrcGlobalDim[1],
                          currentIndex[indexMap[domainElementPosition]],
                          currentIndex[indexMap[domainElementPosition]+1]);

        globIndex = currentIndex[0];
        mulDim = 1;
        for (int k = 1; k < globalDim; ++k)
        {
          mulDim *= gridSrcGlobalDim[k-1];
          globIndex += (currentIndex[k])*mulDim;
        }
        (globalIndexSrcGrid[realGlobalIndex])[i] = globIndex;
      }
      ++realGlobalIndex;
    }

    ++idxLoop[0];
    ++idx;
  }
}

void CDomainAlgorithmTransformation::domainGlobalIndex(const int& index, const int& niGlob, const int& njGlob,
                                                       int& iIndex, int& jIndex)
{
   iIndex = index % niGlob;
   jIndex = index / niGlob;
}
}