#include <stdio.h>
#include <stdlib.h>

#include "verify_indata.h"

void indata_error () {
  fprintf(stderr,
          "Try invoke with -h (or --help);\n  also see the README and HELP files.\n");
  exit(1);
}

void number_of_params (int argc, int oc, int expected) {
  int params = argc - oc - 1;
  if (params != expected) {
    fprintf(stderr,
            "Error: number of parameters (%d) should be %d.\n",
            params, expected);
    indata_error();
  }
}

// TODO
void check_arg_types () { }

void sensible_indata (int miles_one_year_ago,
                      int miles_today,
                      int liters) {
  signed int miles = miles_today - miles_one_year_ago;

  if (miles < 0) {
    fprintf(stderr, "Error: distance (%d miles) less than 0\n", miles);
    indata_error();
  }

  if ((miles == 0) && (liters > 0)) {
    fprintf(stderr,
            "Error: 0 distance (%d miles); used liters (%d) more than 0\n",
            miles, liters);
    indata_error();
  }

  // TODO: if verbose
  /* printf("Miles one year ago: %d\nMiles today: %d\n(Miles: %d)\nLiters: %d\n", */
  /*        miles_one_year_ago, miles_today, miles, liters); */
}