#include <cabinet/magic.hpp>

#include <fcntl.h>
#include <unistd.h>

#include <array>
#include <cerrno>
#include <cstddef>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <print>

using flags = cab::magic::flags;

auto main(int argc, char ** argv) -> int
{
  if (argc != 2)
  {
    std::println(std::cerr, "Expected a filename");
    return EXIT_FAILURE;
  }

  auto magic = cab::magic::open(flags::follow_symlinks | flags::mime_type | flags::forward_errors);
  if (!magic)
  {
    std::println(std::cerr, "Failed to initialize libmagic: {}", magic.error().message());
    return EXIT_FAILURE;
  }

  auto fd = ::open(argv[1], O_RDONLY);
  if (fd < 0)
  {
    std::println(std::cerr, "Failed to determine file type: {}", ::strerror(errno));
    return EXIT_FAILURE;
  }

  std::array<std::byte, 512> buffer{};
  ::read(fd, buffer.data(), buffer.size());
  auto mime_type = magic->process(buffer);
  if (!mime_type)
  {
    std::println(std::cerr, "Failed to determine file type: {}", mime_type.error().message());
    return EXIT_FAILURE;
  }

  std::println("{}: {}", argv[1], mime_type.value());
}