/**
 * @file   linked_cell_list.cpp
 * @author Julian Iseringhausen <isering@ins.uni-bonn.de>
 * @date   Mon Nov 21 13:27:22 2011
 *
 * @brief  A linked cell list implementation.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "base/linked_cell_list.hpp"
#include "comm/comm.hpp"
#include "mg.hpp"

using namespace VMG;

Particle::LinkedCellList::LinkedCellList(const std::list<Particle>& particles,
					 const int& near_field_cells, const Grid& grid)
{
  std::list<Particle>::const_iterator iter;
  Index index_global, index_local;
  LocalIndices local = grid.Local();

  local.BoundaryBegin1() = local.BoundaryEnd1() = 0;
  local.BoundaryBegin2() = local.BoundaryEnd2() = 0;

  for (int i=0; i<3; ++i) {

    if (local.HasHalo1()[i]) {
      local.HaloBegin1()[i] = 0;
      local.HaloEnd1()[i] = near_field_cells+1;
      local.Begin()[i] = near_field_cells+1;
      local.End()[i] = local.Begin()[i] + local.Size()[i];
      local.SizeTotal()[i] = local.Size()[i] +
	                     local.HaloEnd1()[i] - local.HaloBegin1()[i] +
	                     local.HaloEnd2()[i] - local.HaloBegin2()[i];
    }

    if (local.HasHalo2()[i]) {
      local.HaloBegin2()[i] = local.End()[i];
      local.HaloEnd2()[i] = local.HaloBegin2()[i] + near_field_cells+1;
      local.SizeTotal()[i] = local.Size()[i] +
	                     local.HaloEnd1()[i] - local.HaloBegin1()[i] +
	                     local.HaloEnd2()[i] - local.HaloBegin2()[i];
    }
  }

  SetGridSize(grid.Global(), local, grid.Extent());

  for (iter=particles.begin(); iter!=particles.end(); ++iter)
    AddParticle(*iter);
}

void Particle::LinkedCellList::AddParticle(const Particle& p)
{
  const Index global_index = (p.Pos() - Extent().Begin()) / Extent().MeshWidth();
  const Index local_index = global_index - Global().BeginLocal() + Local().Begin();

  if (local_index.IsInBounds(Local().Begin(), Local().End()))
    (*this)(local_index).push_back(Particle(p.Pos(), p.Charge(), 0.0, 0.0, p.Rank(), p.Index()));
  else
    not_my_particles.push_back(Particle(p.Pos(), p.Charge(), 0.0, 0.0, p.Rank(), p.Index()));
}

void Particle::LinkedCellList::AddParticleToComplete(const vmg_float* pos, const vmg_float& charge,
						     const vmg_float& pot, const vmg_float* force,
						     const int& rank, const int& index)
{
  const Index global_index = (Vector(pos) - Extent().Begin()) / Extent().MeshWidth();
  const Index local_index = global_index - Global().BeginLocal() + Local().Begin();

  if (local_index.IsInBounds(0, Local().SizeTotal()))
    (*this)(local_index).push_back(Particle(pos, charge, pot, force, rank, index));
  else
    not_my_particles.push_back(Particle(pos, charge, pot, force, rank, index));
}

void Particle::LinkedCellList::AddParticleToComplete(const Vector& pos, const vmg_float& charge,
						     const vmg_float& pot, const Vector& force,
						     const int& rank, const int& index)
{
  const Index global_index = (pos - Extent().Begin()) / Extent().MeshWidth();
  const Index local_index = global_index - Global().BeginLocal() + Local().Begin();

  if (local_index.IsInBounds(0, Local().SizeTotal()))
    (*this)(local_index).push_back(Particle(pos, charge, pot, force, rank, index));
  else
    not_my_particles.push_back(Particle(pos, charge, pot, force, rank, index));
}

void Particle::LinkedCellList::AddParticleToComplete(const vmg_float* pos, const vmg_float& charge)
{
  const Index global_index = (Vector(pos) - Extent().Begin()) / Extent().MeshWidth();
  const Index local_index = global_index - Global().BeginLocal() + Local().Begin();

  if (local_index.IsInBounds(0, Local().SizeTotal()))
    (*this)(local_index).push_back(Particle(pos, charge));
  else
    not_my_particles.push_back(Particle(pos, charge));
}