#include "./main.h"

void printhelp() {
  fprintf(stderr, "even: a binary by ZachIR to check if a number is even or ");
  fprintf(stderr, "odd.\n");
  fprintf(stderr, "\t-h: prints this help message\n");
  fprintf(stderr, "\t-v: prints the version\n");
  fprintf(stderr, "\t-c: prints the copyright information\n");
  return;
}

void printcopyright() {
  fprintf(stderr, "Copyright (c) 2024 Zachary Smith\n");
  fprintf(stderr, "even is Free software under the MIT license, and is ");
  fprintf(stderr, "provided without warranty of any kind.\n");
  return;
}

void printversion() {
  fprintf(stderr, "even version %s, 2024\n", VERSION);
  return;
}

int main(int argc, char **argv) {
  bool quiet;
  size_t string_length;
  uint8_t digit;

  digit = 0;
  quiet = false;
  string_length = 0;

  if (argc > 1) {
    for (size_t i = 1; i < argc; i++) {
      if (argv[i][0] == '-') {
        switch (argv[i][1]) {
          case 'h':
            printhelp();
            return SUCCESS;
          case 'c':
            printcopyright();
            return SUCCESS;
          case 'v':
            printversion();
            return SUCCESS;
          case 'q':
            quiet = true;
            break;
          default:
            printhelp();
            return -1;
        }
      }
    }
    assert(strlen(argv[argc - 1]) < SIZE_MAX);
    string_length = strlen(argv[argc - 1]);
    digit = argv[argc - 1][string_length - 1];
    digit -= '0';
    if (quiet) {
      if (digit <= 10)
        return ((digit & 1) == 0) ? SUCCESS : ERR;
    } else {
      if ((digit & 1) == 0) {
        fprintf(stdout, "even\n");
      } else {
        fprintf(stdout, "odd\n");
      }
      return SUCCESS;
    }
  }
  return ERR;
}