#include "moab/Core.hpp"
#include "moab/Interface.hpp"
#include "moab/Range.hpp"
#include "MBTagConventions.hpp"
#include "moab/ParallelComm.hpp"
#include "MBParallelConventions.h"
#include <stdlib.h>
#include <iostream>
#include <fstream>

/* ========================================================== */
#define PRINT_LAST_ERROR \
    if (MB_SUCCESS != result) {\
      std::string tmp_str;\
      mb->get_last_error(tmp_str);\
      std::cout << "Failure; message:" << tmp_str << std::endl;\
      delete mb;\
      return result;\
    }
    
/* ========================================================== */

using namespace moab;
using namespace std;

int main(int argc, char **argv)
{

	if (argc!=2) {
		cout<<"Usage: h5m2plt <mesh file name>"<<endl;
		return 0;
	} else {
		if(access(argv[1], R_OK|W_OK)) {
			cout<<"File "<<argv[1]<<" was not found"<<endl;
			return 0;
		}
	}
  
  EntityHandle root;
  
  Tag idtag;

  Interface* mb = new Core;
  if (NULL == mb)
    return 1;
  
  ErrorCode result = MB_SUCCESS;
  
    // Get the ParallelComm instance
  ParallelComm* pcomm = new ParallelComm(mb, MPI_COMM_WORLD);
  int nprocs = pcomm->proc_config().proc_size();
  int rank = pcomm->proc_config().proc_rank();
  MPI_Comm comm = pcomm->proc_config().proc_comm();  

  string options;
  string mesh_file_name;
  
  mesh_file_name = argv[1];

//Reading mesh file
  options = "PARALLEL=READ_PART;PARTITION=PARALLEL_PARTITION;PARALLEL_RESOLVE_SHARED_ENTS";

  if (rank == 0)
    cout << "Reading file " << mesh_file_name << "\n  with options: " << options << endl
         << " on " << nprocs << " processors\n";

  result = mb->load_file(mesh_file_name.c_str(), 0, options.c_str());
  PRINT_LAST_ERROR; 

  cout << "File loaded on processor " << rank << endl;


// Now exchange 1 layer of ghost elements, using vertices as bridge
result = pcomm->exchange_ghost_cells(3, // int ghost_dim,
                             2, // int bridge_dim,
                             1, //int num_layers,
                             2, //int addl_ents,
                             true); // bool store_remote_handles);
PRINT_LAST_ERROR;
  result = mb->tag_get_handle( GLOBAL_ID_TAG_NAME, 1, MB_TYPE_INTEGER, idtag );
  

  Range faces;
  result = mb->get_entities_by_dimension(0, 2, faces);
  PRINT_LAST_ERROR; 
    
  Range cells;
  result = mb->get_entities_by_dimension(0, 3, cells);
  PRINT_LAST_ERROR;
  
Range owned_cells;
result = pcomm->filter_pstatus(cells, PSTATUS_NOT_OWNED, PSTATUS_NOT, -1, &owned_cells);   

Range nonghost_faces;
result = mb->get_adjacencies(owned_cells, 2, true, nonghost_faces, Interface::UNION);
  
root = mb->get_root_set();

int size = nonghost_faces.size();

int *gids = new int[size];
int *gids2 = new int[size];

result = mb->tag_get_data(idtag, nonghost_faces, (void *)gids);    
PRINT_LAST_ERROR;

result = pcomm->exchange_tags(idtag, faces);
PRINT_LAST_ERROR;

result = mb->tag_get_data(idtag, nonghost_faces, (void *)gids2);    
PRINT_LAST_ERROR;

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

	if(gids[i] != gids2[i]){
		cout <<"rank:" << rank << " GLOBAL_ID #" << gids[i] << " HAS CHANGED TO GLOBAL_ID #" << gids2[i]<< endl;
	}		

			
}

//for(int i=0; i<size; i++){

//	if(gids[i] == 30718357){
//		cout <<"rank:" << rank << " GLOBAL_ID #" << gids[i] << endl;
//	}		

//			
//}




if(rank == 0) cout <<"Done" << endl;
delete mb;

return 0;

}