#ifndef MOBIUS_CRYPT_GCRYPT_CIPHER_IMPL_H
#define MOBIUS_CRYPT_GCRYPT_CIPHER_IMPL_H

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// Mobius Forensic Toolkit
// Copyright (C) 2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020,2021,2022,2023,2024 Eduardo Aguiar
//
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option) any later
// version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
// Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
#include <mobius/crypt/cipher_impl_base.h>
#include <mobius/bytearray.h>
#include <gcrypt.h>

namespace mobius::crypt::gcrypt
{
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief libgcrypt cipher adaptor implementation class
//! \author Eduardo Aguiar
//! \see https://www.gnupg.org/documentation/manuals/gcrypt/index.html#SEC_Contents
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
class cipher_impl : public cipher_impl_base
{
public:
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // Constructors and destructor
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  cipher_impl (const std::string&, const std::string&);
  cipher_impl (const cipher_impl&) = delete;
  cipher_impl (cipher_impl&&) = delete;
  ~cipher_impl ();

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // Assignment operators
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  cipher_impl& operator= (const cipher_impl&) = delete;
  cipher_impl& operator= (cipher_impl&&) = delete;

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  //! \brief Get cipher type
  //! \return Cipher type
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  std::string
  get_type () const final
  {
    return type_;
  }

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  //! \brief Return true if it is a cipher stream algorithm
  //! \return true/false
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  bool
  is_stream () const noexcept final
  {
    return is_stream_;
  }

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  //! \brief Return true if it is a cipher block algorithm
  //! \return true/false
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  bool
  is_block () const noexcept final
  {
    return !is_stream_;
  }

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  //! \brief Get block size
  //! \return Block size in bytes
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  std::size_t
  get_block_size () const noexcept final
  {
    return block_size_;
  }

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // Overwritten methods
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  void reset () final;
  void final () final;
  mobius::bytearray encrypt (const mobius::bytearray&) final;
  mobius::bytearray decrypt (const mobius::bytearray&) final;
  void authenticate (const mobius::bytearray&);
  mobius::bytearray get_tag () const;
  bool check_tag (const mobius::bytearray&) const;

  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  // Internal functions
  // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  void set_key (const mobius::bytearray&);
  void set_iv (const mobius::bytearray&);
  void set_counter (const mobius::bytearray&);

private:

  //! \brief Cipher handle
  gcry_cipher_hd_t hd_ = 0;

  //! \brief Cipher block size in bytes
  std::size_t block_size_ = 0;

  //! \brief Cipher type
  std::string type_;

  //! \brief Initialization vector (IV)
  mobius::bytearray iv_;

  //! \brief Counter vector (CV)
  mobius::bytearray cv_;

  //! \brief True if it is a stream cipher
  bool is_stream_ = false;
};

} // namespace mobius::crypt::gcrypt

#endif