/* -*- Mode: C -*- */

#include "mcp_shared.cc"

static bool
fork_player(char *executable, struct player *the_player)
{
  enum { READ = 0, WRITE = 1};

  int pipe_out[2];
  int pipe_in[2];

  if (pipe(pipe_out)  !=  0) return false;
  if (pipe(pipe_in)   !=  0) return false;
  if ((the_player->pid = fork()) == -1) abort();

  if (the_player->pid == 0) {
    /* Child */
    close(pipe_out[READ]);
    close(pipe_in [WRITE]);

    dup2(pipe_in [READ],  CHILD_IN_FD);
    dup2(pipe_out[WRITE], CHILD_OUT_FD);

    setrlimit(RLIMIT_CPU, &cpu_limit);
    setrlimit(RLIMIT_AS, &mem_limit);

	execl(executable, executable, 0);
	perror("execl");
    _exit(EXEC_FAILED);
  } else {
    /* Parent */

    /* Stop the player until it is his turn. */
    if (kill(the_player->pid, SIGSTOP) < 0)
      return false;

    /* Close useless ends of pipes */
    close(pipe_out[WRITE]);
    close(pipe_in [READ]);

    the_player->pipe_from_player = pipe_out[READ];
	the_player->pipe_to_player   = pipe_in[WRITE];
  }

  return true;
}

int
main(int argc, char **argv)
{
  char const *init_state = "O...........................OX......XO...........................";
  fprintf(stderr, "Master Control Program\n");

  int opt;
  while ((opt = getopt(argc, argv, "dT:t:m:M:s:")) != -1) {
    switch (opt) {
    case 'd': debug = true; break;
    case 't': cpu_limit.rlim_cur = strtoul(optarg, NULL, 0); break;
    case 'T': cpu_limit.rlim_max = strtoul(optarg, NULL, 0); break;
    case 'm': mem_limit.rlim_cur = strtoul(optarg, NULL, 0) << 20; break;
    case 'M': mem_limit.rlim_max = strtoul(optarg, NULL, 0) << 20; break;
	case 's': init_state = optarg; break;
    case ':':
    case '?':
      goto usage;
    }
  }

  if (optind + 2 > argc) {
  usage:
    print_usage();
    exit(1);
  }

  setup_signal_handlers();

  if (!fork_player(argv[optind],     &player[0]) ||
      !fork_player(argv[optind + 1], &player[1]))
    exit_msg(EXEC_FAILED, "Unable to fork players.\n");

  game_state state;
  initialize_state(&state, init_state);

  idx_t player_no = state.player() == PLAYER_1 ? 0 : 1;
  while (!is_final_state(&state)) {
    game_move move;
    state.player(static_cast<int>(player_no));

    char timeBuf[64];
    getTimeStr(timeBuf, 64);

    printf("[%s] P%u's turn.\nState:\n", timeBuf, player_no);
	fflush(stdout);
	state.dump_to_stdio();
	//serialize_state(STDOUT_FILENO, &state);
	printf("\n");

    if (!player_move(&player[player_no], &state, &move)) {
      if (debug) {
        printf("No move from player %d.\n", player_no);
        continue;
      }
      exit_msg(exit_reason(CRASH_0 + player_no),
               "No move from player %u.\n", player_no);
    }

    if (!apply_move(&state, &move)) {
	  printf("Invalid move from player %u.\n", player_no);
      exit_msg(exit_reason(INVALID_MOVE_0 + player_no),
               "Invalid move from player %u.\n", player_no);
    }

    printf("P%u moves.\n", player_no);

    player_no = 1 - player_no;
  }

  printf("\nFinal state:\n");
  fflush(stdout);
  serialize_state(STDOUT_FILENO, &state);
  fprintf(stderr, "\n\nEnd of Line.\n");
  printf("\nFinal result: %d : %d\n", state.count_of_type(PLAYER_1),
		 state.count_of_type(PLAYER_2));

  /* Kill players */
  for (int i = 0; i < 2; i++) {
    int status;
    kill(player[i].pid, SIGTERM);
    kill(player[i].pid, SIGCONT);
    waitpid(player[i].pid, &status, 0);
  }

  return 0;
}