import ./make-test-python.nix ({ lib, pkgs, ... }:
let
    slurmconfig = {
      services.slurm = {
        controlMachine = "control";
        nodeName = [ "node[1-3] CPUs=1 State=UNKNOWN" ];
        partitionName = [ "debug Nodes=node[1-3] Default=YES MaxTime=INFINITE State=UP" ];
        extraConfig = ''
          AccountingStorageHost=dbd
          AccountingStorageType=accounting_storage/slurmdbd
        '';
      };
      environment.systemPackages = [ mpitest ];
      networking.firewall.enable = false;
      systemd.tmpfiles.rules = [
        "f /etc/munge/munge.key 0400 munge munge - mungeverryweakkeybuteasytointegratoinatest"
      ];
    };

    mpitest = let
      mpitestC = pkgs.writeText "mpitest.c" ''
        #include <stdio.h>
        #include <stdlib.h>
        #include <mpi.h>

        int
        main (int argc, char *argv[])
        {
          int rank, size, length;
          char name[512];

          MPI_Init (&argc, &argv);
          MPI_Comm_rank (MPI_COMM_WORLD, &rank);
          MPI_Comm_size (MPI_COMM_WORLD, &size);
          MPI_Get_processor_name (name, &length);

          if ( rank == 0 ) printf("size=%d\n", size);

          printf ("%s: hello world from process %d of %d\n", name, rank, size);

          MPI_Finalize ();

          return EXIT_SUCCESS;
        }
      '';
    in pkgs.runCommand "mpitest" {} ''
      mkdir -p $out/bin
      ${pkgs.openmpi}/bin/mpicc ${mpitestC} -o $out/bin/mpitest
    '';
in {
  name = "slurm";

  meta.maintainers = [ lib.maintainers.markuskowa ];

  nodes =
    let
    computeNode =
      { ...}:
      {
        imports = [ slurmconfig ];
        # TODO slurmd port and slurmctld port should be configurations and
        # automatically allowed by the  firewall.
        services.slurm = {
          client.enable = true;
        };
      };
    in {

    control =
      { ...}:
      {
        imports = [ slurmconfig ];
        services.slurm = {
          server.enable = true;
        };
      };

    submit =
      { ...}:
      {
        imports = [ slurmconfig ];
        services.slurm = {
          enableStools = true;
        };
      };

    dbd =
      { pkgs, ... } :
      let
        passFile = pkgs.writeText "dbdpassword" "password123";
      in {
        networking.firewall.enable = false;
        systemd.tmpfiles.rules = [
          "f /etc/munge/munge.key 0400 munge munge - mungeverryweakkeybuteasytointegratoinatest"
        ];
        services.slurm.dbdserver = {
          enable = true;
          storagePassFile = "${passFile}";
        };
        services.mysql = {
          enable = true;
          package = pkgs.mariadb;
          initialScript = pkgs.writeText "mysql-init.sql" ''
            CREATE USER 'slurm'@'localhost' IDENTIFIED BY 'password123';
            GRANT ALL PRIVILEGES ON slurm_acct_db.* TO 'slurm'@'localhost';
          '';
          ensureDatabases = [ "slurm_acct_db" ];
          ensureUsers = [{
            ensurePermissions = { "slurm_acct_db.*" = "ALL PRIVILEGES"; };
            name = "slurm";
          }];
          settings.mysqld = {
            # recommendations from: https://slurm.schedmd.com/accounting.html#mysql-configuration
            innodb_buffer_pool_size="1024M";
            innodb_log_file_size="64M";
            innodb_lock_wait_timeout=900;
          };
        };
      };

    node1 = computeNode;
    node2 = computeNode;
    node3 = computeNode;
  };


  testScript =
  ''
  start_all()

  # Make sure DBD is up after DB initialzation
  with subtest("can_start_slurmdbd"):
      dbd.succeed("systemctl restart slurmdbd")
      dbd.wait_for_unit("slurmdbd.service")
      dbd.wait_for_open_port(6819)

  # there needs to be an entry for the current
  # cluster in the database before slurmctld is restarted
  with subtest("add_account"):
      control.succeed("sacctmgr -i add cluster default")
      # check for cluster entry
      control.succeed("sacctmgr list cluster | awk '{ print $1 }' | grep default")

  with subtest("can_start_slurmctld"):
      control.succeed("systemctl restart slurmctld")
      control.wait_for_unit("slurmctld.service")

  with subtest("can_start_slurmd"):
      for node in [node1, node2, node3]:
          node.succeed("systemctl restart slurmd.service")
          node.wait_for_unit("slurmd")

  # Test that the cluster works and can distribute jobs;

  with subtest("run_distributed_command"):
      # Run `hostname` on 3 nodes of the partition (so on all the 3 nodes).
      # The output must contain the 3 different names
      submit.succeed("srun -N 3 hostname | sort | uniq | wc -l | xargs test 3 -eq")

      with subtest("check_slurm_dbd"):
          # find the srun job from above in the database
          control.succeed("sleep 5")
          control.succeed("sacct | grep hostname")

  with subtest("run_PMIx_mpitest"):
      submit.succeed("srun -N 3 --mpi=pmix mpitest | grep size=3")
  '';
})