#ifndef IO_HH
#define IO_HH

#include <cstddef>
#include <expected>
#include <memory>
#include <string>

namespace io {

enum class ReadError {
  Error,
  Eof,
  InvalidData,  // invalid data read (not used by raw file)
  MaxTooSmall,  // max argument needs to be bigger (not used by raw file)
};

enum class OpenError {
  NoSuchFile,
  NoAccess,
  Error,
};

class Reader {
 public:
  virtual ~Reader() = default;

  [[nodiscard]] virtual std::expected<size_t, ReadError> read(void* dst,
                                                              size_t max) = 0;
  [[nodiscard]] virtual std::expected<size_t, ReadError> skip(size_t max) = 0;

  [[nodiscard]] std::expected<size_t, ReadError> repeat_read(void* dst,
                                                             size_t max);
  [[nodiscard]] std::expected<size_t, ReadError> repeat_skip(size_t max);

 protected:
  Reader() = default;

  Reader(Reader const&) = delete;
  Reader& operator=(Reader const&) = delete;
};

[[nodiscard]] std::expected<std::unique_ptr<Reader>, OpenError> open(
    const std::string& file_path);
[[nodiscard]] std::expected<std::unique_ptr<Reader>, OpenError> openat(
    int dirfd, const std::string& file_path);
[[nodiscard]] std::unique_ptr<Reader> memory(std::string data);

}  // namespace io

#endif  // IO_HH