#include "mpi.h"
#include <iostream>

using namespace std;

#define TAG_TEST 500

int main(int argc, char** argv) {
  int commSize, commRank, result;

  result = MPI_Init(&argc, &argv);
  if (result != MPI_SUCCESS) {
    cerr << "Error initializing MPI application!" << endl;
    MPI_Abort(MPI_COMM_WORLD, -1);
  }
  
  MPI_Comm_size(MPI_COMM_WORLD, &commSize);
  MPI_Comm_rank(MPI_COMM_WORLD, &commRank);
 
  int flag;

  MPI_Comm masterComm;
  MPI_Comm_get_parent(&masterComm);
  
  int size;
  MPI_Comm_remote_size(masterComm, &size);
  if (size != 1) {
    cerr << "Parent master doesn't have size 1" << endl;
    return 1;
  }

  MPI_Send(&size, 1, MPI_INT, 0, TAG_TEST, masterComm);

  // spawn slave
  MPI_Info ourInfo;
  MPI_Info_create(&ourInfo);
  MPI_Comm slaveComm;
  MPI_Comm_spawn("/home/pthyseba/workspace/OCTOPUS/test-slave", MPI_ARGV_NULL, 1, ourInfo, 0, MPI_COMM_SELF, &slaveComm, MPI_ERRCODES_IGNORE);

  MPI_Status s;
  int data;
  for (int i = 0;; i++) {
    MPI_Iprobe(0, TAG_TEST, slaveComm, &flag, &s);
    if (flag > 0) {
        cout << "Worker: message from slave detected after " << i << " probes" << endl;
        MPI_Recv(&data, 1, MPI_INT, 0, TAG_TEST, slaveComm, &s);
        break;
     }
  }
  
  cout << "Worker: received data from slave: " << data << endl;

  MPI_Finalize();
  return 0;
}