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

#include "util/versie.h"
#include "util/loop_files.h"
#include "io/read_file.h"

static void usage(FILE *f) {
  fprintf(f,
      "Gebruik: kat [-hV] <bestand...>\n"
      "\n"
      "Schakel bestanden aaneen naar standaard uitvoer.\n"
      "\n"
      "  -h    Toon deze hulptekst\n"
      "  -V    Toon versienummer\n");
}

// Returns pointer to argument array containing the file names
static char** parse_options(int argc, char **argv) {
  int opt;
  while ((opt = getopt(argc, argv, "hV")) != -1) {
    switch (opt) {
      case 'h':
        usage(stdout);
        exit(0);

      case 'V':
        drukkedoos_print_versie(stdout);
        exit(0);

      case '?':
        fprintf(stderr, "kat: Ongeldige optie: -%c\n", optopt);
        usage(stderr);
        exit(1);
    }
  }

  return argv + optind;
}

static int process(struct filebuf *fb, char*, bool) {
  fwrite(fb->buf, 1, fb->sz, stdout);
  free_filebuf(fb);
  return 0;
}

// TODO: be smarter, kat doesn't have to read the whole file in memory (for
// unmappable files)

int entry_kat(int argc, char **argv) {
  char **args = parse_options(argc, argv);
  return loop_files(args, process);
}