#include "moab/Core.hpp"
#include "moab/ReorderTool.hpp"

using namespace moab;

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

  ErrorCode rval;

  moab::Core mb_instance;
  moab::Interface& moab = mb_instance;

  const char *option;
  option = "";
  rval = moab.load_file("4seasons.h5m", 0, option);

  const char GLOBAL_ID_NAME[] = "GLOBAL_ID";


  Range meshsets;
  rval = moab.get_entities_by_type(0,MBENTITYSET,meshsets,true);

  // get/create various tags
  Tag th_gid;
  rval = moab.tag_get_handle(GLOBAL_ID_NAME,1,MB_TYPE_INTEGER,th_gid,MB_TAG_DENSE);

  Range ents,to_delete;
  rval = moab.get_entities_by_handle(0,ents);

  int gid = 0;

  // Set gid and select ents to delete
  bool del = false;
  for(Range::iterator eit = ents.begin();eit!=ents.end();eit++) {
    if(del) {
      del = false;
      to_delete.insert(*eit);
    } else {
      del = true;
    }
  }

  for(Range::iterator mit = meshsets.begin();mit!=meshsets.end();mit++) {
    rval = moab.remove_entities(*mit,to_delete);
  }

  rval = moab.delete_entities(to_delete);

  for(int dd=3;dd>=0;dd--) {
    Range dim_ents = ents.subset_by_dimension(dd);
    int gid = 0;
    for(Range::iterator tit = ents.begin();tit!=ents.end();tit++) {
      del = true;
      rval = moab.tag_set_data(th_gid,&*tit,1,&gid);
      gid++;
    }
  }

  // do reorder
  ReorderTool tool(&mb_instance);
  Tag mapping;
  rval = tool.handle_order_from_int_tag(th_gid, -1, mapping );
  rval = tool.reorder_entities( mapping );


  return 0;
}