/*
 * Copyright (c) 2010-2020 Belledonne Communications SARL.
 *
 * This file is part of linphone-desktop
 * (see https://www.linphone.org).
 *
 * 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 3 of the License, 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/>.
 */

#ifndef FILE_DOWNLOADER_H_
#define FILE_DOWNLOADER_H_

#include <QObject>
#include <QtNetwork>

// =============================================================================

class QSslError;

class FileDownloader : public QObject {
  Q_OBJECT;

  // TODO: Add an error property to use in UI.

  Q_PROPERTY(QUrl url READ getUrl WRITE setUrl NOTIFY urlChanged);
  Q_PROPERTY(QString downloadFolder READ getDownloadFolder WRITE setDownloadFolder NOTIFY downloadFolderChanged);
  Q_PROPERTY(qint64 readBytes READ getReadBytes NOTIFY readBytesChanged);
  Q_PROPERTY(qint64 totalBytes READ getTotalBytes NOTIFY totalBytesChanged);
  Q_PROPERTY(bool downloading READ getDownloading NOTIFY downloadingChanged);

public:
  FileDownloader (QObject *parent = Q_NULLPTR) : QObject(parent) {
    // See: https://bugreports.qt.io/browse/QTBUG-57390
    mTimeout.setInterval(DefaultTimeout);
    QObject::connect(&mTimeout, &QTimer::timeout, this, &FileDownloader::handleTimeout);
  }

  ~FileDownloader () { if (mNetworkReply) mNetworkReply->abort(); }

  Q_INVOKABLE void download ();
  Q_INVOKABLE bool remove();

  QUrl getUrl () const;
  void setUrl (const QUrl &url);

  QString getDownloadFolder () const;
  void setDownloadFolder (const QString &downloadFolder);

signals:
  void urlChanged (const QUrl &url);
  void downloadFolderChanged (const QString &downloadFolder);
  void readBytesChanged (qint64 readBytes);
  void totalBytesChanged (qint64 totalBytes);
  void downloadingChanged (bool downloading);
  void downloadFinished (const QString &filePath);
  void downloadFailed();

private:
  qint64 getReadBytes () const;
  void setReadBytes (qint64 readBytes);

  qint64 getTotalBytes () const;
  void setTotalBytes (qint64 totalBytes);

  bool getDownloading () const;
  void setDownloading (bool downloading);

  void emitOutputError ();

  void cleanDownloadEnd ();

  void handleReadyData ();
  void handleDownloadFinished ();

  void handleError (QNetworkReply::NetworkError code);
  void handleSslErrors (const QList<QSslError> &errors);
  void handleTimeout ();
  void handleDownloadProgress (qint64 readBytes, qint64 totalBytes);

  QUrl mUrl;
  QString mDownloadFolder;
  QFile mDestinationFile;

  qint64 mReadBytes = 0;
  qint64 mTotalBytes = 0;
  bool mDownloading = false;

  QPointer<QNetworkReply> mNetworkReply;
  QNetworkAccessManager mManager;

  qint64 mTimeoutReadBytes;
  QTimer mTimeout;

  static constexpr int DefaultTimeout = 5000;
};

#endif // FILE_DOWNLOADER_H_