/**
 * Copyright (C) 2021 Saturneric
 *
 * 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.
 *
 * GpgFrontend 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 GpgFrontend. If not, see <https://www.gnu.org/licenses/>.
 *
 * The initial version of the source code is inherited from
 * the gpg4usb project, which is under GPL-3.0-or-later.
 *
 * All the source code of GpgFrontend was modified and released by
 * Saturneric<eric@bktus.com> starting on May 12, 2021.
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 */

#include "UserInterfaceUtils.h"

#include <utility>
#include <vector>

#include "core/common/CoreCommonUtil.h"
#include "core/function/FileOperator.h"
#include "core/function/GlobalSettingStation.h"
#include "core/function/gpg/GpgKeyGetter.h"
#include "easylogging++.h"
#include "ui/SignalStation.h"
#include "ui/dialog/WaitingDialog.h"
#include "ui/widgets/TextEdit.h"

namespace GpgFrontend::UI {

std::unique_ptr<GpgFrontend::UI::CommonUtils>
    GpgFrontend::UI::CommonUtils::instance_ = nullptr;

void show_verify_details(QWidget *parent, InfoBoardWidget *info_board,
                         GpgError error, const GpgVerifyResult &verify_result) {
  // take out result
  info_board->ResetOptionActionsMenu();
  info_board->AddOptionalAction("Show Verify Details", [=]() {
    VerifyDetailsDialog(parent, error, verify_result);
  });
}

void import_unknown_key_from_keyserver(
    QWidget *parent, const GpgVerifyResultAnalyse &verify_res) {
  QMessageBox::StandardButton reply;
  reply = QMessageBox::question(
      parent, _("Public key not found locally"),
      _("There is no target public key content in local for GpgFrontend to "
        "gather enough information about this Signature. Do you want to "
        "import the public key from Keyserver now?"),
      QMessageBox::Yes | QMessageBox::No);
  if (reply == QMessageBox::Yes) {
    auto dialog = KeyServerImportDialog(true, parent);
    auto key_ids = std::make_unique<KeyIdArgsList>();
    auto *signature = verify_res.GetSignatures();
    while (signature != nullptr) {
      LOG(INFO) << "signature fpr" << signature->fpr;
      key_ids->push_back(signature->fpr);
      signature = signature->next;
    }
    dialog.show();
    dialog.SlotImport(key_ids);
  }
}

void refresh_info_board(InfoBoardWidget *info_board, int status,
                        const std::string &report_text) {
  if (status < 0)
    info_board->SlotRefresh(QString::fromStdString(report_text),
                            INFO_ERROR_CRITICAL);
  else if (status > 0)
    info_board->SlotRefresh(QString::fromStdString(report_text), INFO_ERROR_OK);
  else
    info_board->SlotRefresh(QString::fromStdString(report_text),
                            INFO_ERROR_WARN);
}

void process_result_analyse(TextEdit *edit, InfoBoardWidget *info_board,
                            const GpgResultAnalyse &result_analyse) {
  info_board->AssociateTabWidget(edit->tab_widget_);
  refresh_info_board(info_board, result_analyse.GetStatus(),
                     result_analyse.GetResultReport());
}

void process_result_analyse(TextEdit *edit, InfoBoardWidget *info_board,
                            const GpgResultAnalyse &result_analyse_a,
                            const GpgResultAnalyse &result_analyse_b) {
  LOG(INFO) << "process_result_analyse Started";

  info_board->AssociateTabWidget(edit->tab_widget_);

  refresh_info_board(
      info_board,
      std::min(result_analyse_a.GetStatus(), result_analyse_b.GetStatus()),
      result_analyse_a.GetResultReport() + result_analyse_b.GetResultReport());
}

void process_operation(QWidget *parent, const std::string &waiting_title,
                       const std::function<void()> &func) {
  auto thread = QThread::create(func);
  QApplication::connect(thread, &QThread::finished, thread,
                        &QThread::deleteLater);
  thread->start();

  auto *dialog =
      new WaitingDialog(QString::fromStdString(waiting_title), parent);
  while (thread->isRunning()) {
    QApplication::processEvents();
  }
  dialog->close();
}

CommonUtils *CommonUtils::GetInstance() {
  if (instance_ == nullptr) {
    instance_ = std::make_unique<CommonUtils>();
  }
  return instance_.get();
}

CommonUtils::CommonUtils() : QWidget(nullptr) {
  LOG(INFO) << "common utils created";

  connect(CoreCommonUtil::GetInstance(), &CoreCommonUtil::SignalGnupgNotInstall,
          this, &CommonUtils::SignalGnupgNotInstall);
  connect(this, &CommonUtils::SignalKeyStatusUpdated,
          SignalStation::GetInstance(),
          &SignalStation::SignalKeyDatabaseRefresh);
  connect(this, &CommonUtils::SignalKeyDatabaseRefreshDone,
          SignalStation::GetInstance(),
          &SignalStation::SignalKeyDatabaseRefreshDone);

  // directly connect to SignalKeyStatusUpdated
  // to avoid the delay of signal emitting
  // when the key database is refreshed
  connect(SignalStation::GetInstance(),
          &SignalStation::SignalKeyDatabaseRefresh, this,
          &CommonUtils::slot_update_key_status);

  connect(this, &CommonUtils::SignalGnupgNotInstall, this, []() {
    QMessageBox::critical(
        nullptr, _("ENV Loading Failed"),
        _("Gnupg(gpg) is not installed correctly, please follow the "
          "ReadME "
          "instructions in Github to install Gnupg and then open "
          "GpgFrontend."));
    QCoreApplication::quit();
  });
}

void CommonUtils::SlotImportKeys(QWidget *parent,
                                 const std::string &in_buffer) {
  GpgImportInformation result = GpgKeyImportExporter::GetInstance().ImportKey(
      std::make_unique<ByteArray>(in_buffer));
  emit SignalKeyStatusUpdated();
  new KeyImportDetailDialog(result, false, parent);
}

void CommonUtils::SlotImportKeyFromFile(QWidget *parent) {
  QString file_name = QFileDialog::getOpenFileName(
      this, _("Open Key"), QString(),
      QString(_("Key Files")) + " (*.asc *.txt);;" + _("Keyring files") +
          " (*.gpg);;All Files (*)");
  if (!file_name.isNull()) {
    QByteArray key_buffer;
    if (!FileOperator::ReadFile(file_name, key_buffer)) {
      QMessageBox::critical(nullptr, _("File Open Failed"),
                            _("Failed to open file: ") + file_name);
      return;
    }
    SlotImportKeys(parent, key_buffer.toStdString());
  }
}

void CommonUtils::SlotImportKeyFromKeyServer(QWidget *parent) {
  auto dialog = new KeyServerImportDialog(false, parent);
  dialog->show();
}

void CommonUtils::SlotImportKeyFromClipboard(QWidget *parent) {
  QClipboard *cb = QApplication::clipboard();
  SlotImportKeys(parent,
                 cb->text(QClipboard::Clipboard).toUtf8().toStdString());
}

void CommonUtils::SlotExecuteGpgCommand(
    const QStringList &arguments,
    const std::function<void(QProcess *)> &interact_func) {
  QEventLoop looper;
  auto dialog = new WaitingDialog(_("Processing"), nullptr);
  dialog->show();
  auto *gpg_process = new QProcess(&looper);
  gpg_process->setProcessChannelMode(QProcess::MergedChannels);

  connect(gpg_process,
          qOverload<int, QProcess::ExitStatus>(&QProcess::finished), &looper,
          &QEventLoop::quit);
  connect(gpg_process,
          qOverload<int, QProcess::ExitStatus>(&QProcess::finished), dialog,
          &WaitingDialog::deleteLater);
  connect(gpg_process, &QProcess::errorOccurred, &looper, &QEventLoop::quit);
  connect(gpg_process, &QProcess::started,
          []() -> void { LOG(ERROR) << "Gpg Process Started Success"; });
  connect(gpg_process, &QProcess::readyReadStandardOutput,
          [interact_func, gpg_process]() { interact_func(gpg_process); });
  connect(gpg_process, &QProcess::errorOccurred, this, [=]() -> void {
    LOG(ERROR) << "Error in Process";
    dialog->close();
    QMessageBox::critical(nullptr, _("Failure"),
                          _("Failed to execute command."));
  });
  connect(gpg_process,
          qOverload<int, QProcess::ExitStatus>(&QProcess::finished), this,
          [=](int, QProcess::ExitStatus status) {
            dialog->close();
            if (status == QProcess::NormalExit)
              QMessageBox::information(nullptr, _("Success"),
                                       _("Succeed in executing command."));
            else
              QMessageBox::information(nullptr, _("Warning"),
                                       _("Finished executing command."));
          });

  gpg_process->setProgram(GpgContext::GetInstance().GetInfo().AppPath.c_str());
  gpg_process->setArguments(arguments);
  gpg_process->start();
  looper.exec();
  dialog->close();
  dialog->deleteLater();
}

void CommonUtils::SlotImportKeyFromKeyServer(
    const KeyIdArgsList &key_ids, const ImportCallbackFunctiopn &callback) {
  std::string target_keyserver;
  if (target_keyserver.empty()) {
    try {
      auto &settings = GlobalSettingStation::GetInstance().GetUISettings();

      target_keyserver = settings.lookup("keyserver.default_server").c_str();

      LOG(INFO) << _("Set target Key Server to default Key Server")
                << target_keyserver;
    } catch (...) {
      LOG(ERROR) << _("Cannot read default_keyserver From Settings");
      QMessageBox::critical(
          nullptr, _("Default Keyserver Not Found"),
          _("Cannot read default keyserver from your settings, "
            "please set a default keyserver first"));
      return;
    }
  }

  auto thread = QThread::create([target_keyserver, key_ids, callback]() {
    QUrl target_keyserver_url(target_keyserver.c_str());

    auto network_manager = std::make_unique<QNetworkAccessManager>();
    // LOOP
    decltype(key_ids.size()) current_index = 1, all_index = key_ids.size();
    for (const auto &key_id : key_ids) {
      // New Req Url
      QUrl req_url(
          target_keyserver_url.scheme() + "://" + target_keyserver_url.host() +
          "/pks/lookup?op=get&search=0x" + key_id.c_str() + "&options=mr");

      LOG(INFO) << "request url" << req_url.toString().toStdString();

      // Waiting for reply
      QNetworkReply *reply = network_manager->get(QNetworkRequest(req_url));
      QEventLoop loop;
      connect(reply, &QNetworkReply::finished, &loop, &QEventLoop::quit);
      loop.exec();

      // Get Data
      auto key_data = reply->readAll();
      auto key_data_ptr =
          std::make_unique<ByteArray>(key_data.data(), key_data.size());

      // Detect status
      std::string status;
      auto error = reply->error();
      if (error != QNetworkReply::NoError) {
        switch (error) {
          case QNetworkReply::ContentNotFoundError:
            status = _("Key Not Found");
            break;
          case QNetworkReply::TimeoutError:
            status = _("Timeout");
            break;
          case QNetworkReply::HostNotFoundError:
            status = _("Key Server Not Found");
            break;
          default:
            status = _("Connection Error");
        }
      }

      reply->deleteLater();

      // Try importing
      GpgImportInformation result =
          GpgKeyImportExporter::GetInstance().ImportKey(
              std::move(key_data_ptr));

      if (result.imported == 1) {
        status = _("The key has been updated");
      } else {
        status = _("No need to update the key");
      }
      callback(key_id, status, current_index, all_index);
      current_index++;
    }
  });

  connect(thread, &QThread::finished, thread, &QThread::deleteLater);
  thread->start();
}

void CommonUtils::slot_update_key_status() {
  LOG(INFO) << "called";

  std::vector<QThread *> threads;

  // flush key cache for all GpgKeyGetter Intances.
  for (const auto &channel_id : GpgKeyGetter::GetAllChannelId()) {
    // multi threading
    auto *thread = QThread::create([channel_id]() {
      LOG(INFO) << "thread start"
                << "channel:" << channel_id;
      GpgKeyGetter::GetInstance(channel_id).FlushKeyCache();
    });
    thread->start();
    threads.push_back(thread);
  }

  for (auto *thread : threads) {
    thread->wait();
    thread->deleteLater();
  }

  emit SignalKeyDatabaseRefreshDone();
  LOG(INFO) << "finished";
}

}  // namespace GpgFrontend::UI