#include <iostream>
#include <mpi.h>
#include <stdlib.h>
#include <cstring>

using namespace std;

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

    int ProcNum, ProcRank, N = 0;
    MPI_Status Status;

    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &ProcNum);
    MPI_Comm_rank(MPI_COMM_WORLD, &ProcRank);

    //--------------------------
    N = (argc >= 2) ? N = stoi(argv[1]) : N = 4;
    //--------------------------
    if (N == 0) {
        MPI_Finalize();
        return 0;
    }
    if (ProcRank == 0) {

        int x = 0;
        bool exit = false;
        char m[10];
        while (exit != true) {
            cout << "Choose 1 to push, 2 to pop, 3 to exit" << endl;
            cin >> x;
            if (x == 1) {
                //push
                cout << "Plese enter a push value: ";
                cin >> m;
                MPI_Send(&m, 10, MPI_CHAR, 1, 1, MPI_COMM_WORLD);
            }
            if (x == 2) {
                //pop
                MPI_Send(&m, 1, MPI_INT, 1, 2, MPI_COMM_WORLD);
            }
            if (x == 3) {
                //exit
                for (int i = 1; i < ProcNum; i++) {
                    MPI_Send(&m, 1, MPI_INT, i, 4, MPI_COMM_WORLD);
                }
                exit = true;
            }
        }
    } else {
        char m[10];
        bool exit = false;
        bool msg = false;
        char message[10];

        while (exit != true) {
            MPI_Recv(&m, 10, MPI_CHAR, MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &Status);
            cout << "Okey man I`m " << ProcRank << " and I get message " << m << endl;
            if (Status.MPI_TAG == 4) {
                cout << "I`m off" << endl;
                exit = true;
            }

            if (Status.MPI_TAG == 1) {

                if ((msg == true) && (ProcRank == ProcNum - 1)) {
                    cout << "ProcRank = " << ProcRank << " ProcNum = " << ProcNum << endl;
                    cout << "QUEUE IS FULL!!!";
                    break;
                }
                if (msg == true) {
                    MPI_Send(&m, 10, MPI_CHAR, ProcRank + 1, 1, MPI_COMM_WORLD);
                }

                if (msg == false) {
                    strcpy(message, m);
                    msg = true;
                    cout << "IT IS MY PUSH MESSAGE " << message << endl;
                }
            }
        }
    }
    MPI_Finalize();
    return 0;
}