/**
 * This file is part of GpgFrontend.
 *
 * GpgFrontend 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 3 of the License, or
 * (at your option) any later version.
 *
 * Foobar 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 Foobar.  If not, see <https://www.gnu.org/licenses/>.
 *
 * The initial version of the source code is inherited from gpg4usb-team.
 * Their source code version also complies with GNU General Public License.
 *
 * The source code version of this software was modified and released
 * by Saturneric<eric@bktus.com> starting on May 12, 2021.
 *
 */

#include "gpg/function/GpgKeyOpera.h"

#include <boost/asio/read_until.hpp>
#include <boost/date_time/posix_time/conversion.hpp>
#include <boost/process/async_pipe.hpp>
#include <memory>
#include <string>
#include <vector>

#include "gpg/GpgConstants.h"
#include "gpg/GpgGenKeyInfo.h"
#include "gpg/function/GpgCommandExecutor.h"
#include "gpg/function/GpgKeyGetter.h"

/**
 * Delete keys
 * @param uidList key ids
 */
void GpgFrontend::GpgKeyOpera::DeleteKeys(
    GpgFrontend::KeyIdArgsListPtr key_ids) {
  GpgError err;
  for (const auto& tmp : *key_ids) {
    auto key = GpgKeyGetter::GetInstance().GetKey(tmp);
    if (key.good()) {
      LOG(INFO) << "GpgKeyOpera DeleteKeys Get Key Good";
      err = check_gpg_error(gpgme_op_delete(ctx, gpgme_key_t(key), 1));
      assert(gpg_err_code(err) == GPG_ERR_NO_ERROR);
    } else
      LOG(WARNING) << "GpgKeyOpera DeleteKeys Get Key Bad";
  }
}

/**
 * Set the expire date and time of a key pair(actually the master key) or subkey
 * @param key target key pair
 * @param subkey null if master key
 * @param expires date and time
 * @return if successful
 */
GpgFrontend::GpgError GpgFrontend::GpgKeyOpera::SetExpire(
    const GpgKey& key, const SubkeyId& subkey_fpr,
    std::unique_ptr<boost::gregorian::date>& expires) {
  unsigned long expires_time = 0;
  if (expires != nullptr) {
    using namespace boost::posix_time;
    using namespace std::chrono;
    expires_time = to_time_t(ptime(*expires)) -
                   system_clock::to_time_t(system_clock::now());
  }

  LOG(INFO) << "GpgFrontend::GpgKeyOpera::SetExpire" << key.id() << subkey_fpr
            << expires_time;

  GpgError err;
  if (subkey_fpr.empty())
    err = gpgme_op_setexpire(ctx, gpgme_key_t(key), expires_time, nullptr, 0);
  else
    err = gpgme_op_setexpire(ctx, gpgme_key_t(key), expires_time,
                             subkey_fpr.c_str(), 0);

  return err;
}

/**
 * Generate revoke cert of a key pair
 * @param key target key pair
 * @param outputFileName out file name(path)
 * @return the process doing this job
 */
void GpgFrontend::GpgKeyOpera::GenerateRevokeCert(
    const GpgKey& key, const std::string& output_file_name) {
  auto args = std::vector<std::string>{"--command-fd", "0",
                                       "--status-fd",  "1",
                                       "-o",           output_file_name.c_str(),
                                       "--gen-revoke", key.fpr().c_str()};

  using boost::process::async_pipe;
  GpgCommandExecutor::GetInstance().Execute(
      args, [](async_pipe& in, async_pipe& out) -> void {
        boost::asio::streambuf buff;
        boost::asio::read_until(in, buff, '\n');

        std::string line;
        std::istream is(&buff);
        is >> line;
        // Code From Gpg4Win
      });
}

/**
 * Generate a new key pair
 * @param params key generation args
 * @return error information
 */
GpgFrontend::GpgError GpgFrontend::GpgKeyOpera::GenerateKey(
    const std::unique_ptr<GenKeyInfo>& params) {
  auto userid_utf8 = params->getUserid();
  const char* userid = userid_utf8.c_str();
  auto algo_utf8 = params->getAlgo() + params->getKeySizeStr();

  LOG(INFO) << "GpgFrontend::GpgKeyOpera::GenerateKey Params"
            << params->getAlgo() << params->getKeySizeStr();

  const char* algo = algo_utf8.c_str();
  unsigned long expires = 0;
  {
    using namespace boost::posix_time;
    using namespace std::chrono;
    expires = to_time_t(ptime(params->getExpired())) -
              system_clock::to_time_t(system_clock::now());
  }

  unsigned int flags = 0;

  if (!params->isSubKey()) flags |= GPGME_CREATE_CERT;
  if (params->isAllowEncryption()) flags |= GPGME_CREATE_ENCR;
  if (params->isAllowSigning()) flags |= GPGME_CREATE_SIGN;
  if (params->isAllowAuthentication()) flags |= GPGME_CREATE_AUTH;
  if (params->isNonExpired()) flags |= GPGME_CREATE_NOEXPIRE;
  if (params->isNoPassPhrase()) flags |= GPGME_CREATE_NOPASSWD;

  LOG(INFO) << "GpgFrontend::GpgKeyOpera::GenerateKey Args: " << userid << algo
            << expires << flags;

  auto err = gpgme_op_createkey(ctx, userid, algo, 0, expires, nullptr, flags);
  return check_gpg_error(err);
}

/**
 * Generate a new subkey of a certain key pair
 * @param key target key pair
 * @param params opera args
 * @return error info
 */
GpgFrontend::GpgError GpgFrontend::GpgKeyOpera::GenerateSubkey(
    const GpgKey& key, const std::unique_ptr<GenKeyInfo>& params) {
  if (!params->isSubKey()) return GPG_ERR_CANCELED;

  auto algo_utf8 = (params->getAlgo() + params->getKeySizeStr());
  const char* algo = algo_utf8.c_str();
  unsigned long expires = 0;
  {
    using namespace boost::posix_time;
    using namespace std::chrono;
    expires = to_time_t(ptime(params->getExpired())) -
              system_clock::to_time_t(system_clock::now());
  }
  unsigned int flags = 0;

  if (!params->isSubKey()) flags |= GPGME_CREATE_CERT;
  if (params->isAllowEncryption()) flags |= GPGME_CREATE_ENCR;
  if (params->isAllowSigning()) flags |= GPGME_CREATE_SIGN;
  if (params->isAllowAuthentication()) flags |= GPGME_CREATE_AUTH;
  if (params->isNonExpired()) flags |= GPGME_CREATE_NOEXPIRE;

  flags |= GPGME_CREATE_NOPASSWD;

  LOG(INFO) << "GpgFrontend::GpgKeyOpera::GenerateSubkey Args: " << key.id()
            << algo << expires << flags;

  auto err =
      gpgme_op_createsubkey(ctx, gpgme_key_t(key), algo, 0, expires, flags);
  return check_gpg_error(err);
}