// This file is part of RSS Guard.
//
// Copyright (C) 2011-2016 by Martin Rotter <rotter.martinos@gmail.com>
//
// RSS Guard 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.
//
// RSS Guard 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 RSS Guard. If not, see <http://www.gnu.org/licenses/>.

#include "network-web/networkfactory.h"

#include "definitions/definitions.h"
#include "miscellaneous/settings.h"
#include "network-web/silentnetworkaccessmanager.h"
#include "network-web/downloader.h"

#include <QEventLoop>
#include <QTimer>
#include <QIcon>
#include <QPixmap>
#include <QTextDocument>


NetworkFactory::NetworkFactory() {
}

QStringList NetworkFactory::extractFeedLinksFromHtmlPage(const QUrl &url, const QString &html) {
  QStringList feeds;
  const QRegExp rx(FEED_REGEX_MATCHER, Qt::CaseInsensitive);
  const QRegExp rx_href(FEED_HREF_REGEX_MATCHER, Qt::CaseInsensitive);

  for (int pos = 0; (pos = rx.indexIn(html, pos)) != -1; pos += rx.matchedLength()) {
    QString link_element = html.mid(pos, rx.matchedLength());

    if (rx_href.indexIn(link_element) != -1) {
      QString href_attribute = rx_href.capturedTexts().at(0);
      QString feed_link = href_attribute.mid(6, href_attribute.size() - 7);

      if (feed_link.startsWith(QL1S("//"))) {
        feed_link = QString(URI_SCHEME_HTTP) + feed_link.mid(2);
      }
      else if (feed_link.startsWith(QL1C('/'))) {
        feed_link = url.toString(QUrl::RemovePath | QUrl::RemoveQuery | QUrl::StripTrailingSlash) + feed_link;
      }

      feeds.append(feed_link);
    }
  }

  return feeds;
}

QString NetworkFactory::networkErrorText(QNetworkReply::NetworkError error_code) {
  switch (error_code) {
    case QNetworkReply::ProtocolUnknownError:
    case QNetworkReply::ProtocolFailure:
      //: Network status.
      return tr("protocol error");

    case QNetworkReply::ContentAccessDenied:
      return tr("access to content was denied");

    case QNetworkReply::HostNotFoundError:
      //: Network status.
      return tr("host not found");

    case QNetworkReply::OperationCanceledError:
    case QNetworkReply::TimeoutError:
      return tr("connection timed out or was cancelled");

    case QNetworkReply::RemoteHostClosedError:
    case QNetworkReply::ConnectionRefusedError:
      //: Network status.
      return tr("connection refused");

    case QNetworkReply::ProxyTimeoutError:
      //: Network status.
      return tr("connection timed out");

    case QNetworkReply::SslHandshakeFailedError:
      //: Network status.
      return tr("SSL handshake failed");

    case QNetworkReply::ProxyConnectionClosedError:
    case QNetworkReply::ProxyConnectionRefusedError:
      //: Network status.
      return tr("proxy server connection refused");

    case QNetworkReply::TemporaryNetworkFailureError:
      //: Network status.
      return tr("temporary failure");

    case QNetworkReply::AuthenticationRequiredError:
      //: Network status.
      return tr("authentication failed");

    case QNetworkReply::ProxyAuthenticationRequiredError:
      //: Network status.
      return tr("proxy authentication required");

    case QNetworkReply::ProxyNotFoundError:
      //: Network status.
      return tr("proxy server not found");

    case QNetworkReply::NoError:
      //: Network status.
      return tr("no errors");

    case QNetworkReply::UnknownContentError:
      //: Network status.
      return tr("unknown content");

    case QNetworkReply::ContentNotFoundError:
      //: Network status.
      return tr("content not found");

    default:
      //: Network status.
      return tr("unknown error");
  }
}

QNetworkReply::NetworkError NetworkFactory::downloadIcon(const QList<QString> &urls, int timeout, QIcon &output) {
  QNetworkReply::NetworkError network_result;

  foreach (const QString &url, urls) {
    const QString google_s2_with_url = QString("http://www.google.com/s2/favicons?domain=%1").arg(url.toHtmlEscaped());
    QByteArray icon_data;
    network_result =  performNetworkOperation(google_s2_with_url, timeout, QByteArray(), QString(), icon_data,
                                              QNetworkAccessManager::GetOperation).first;

    if (network_result == QNetworkReply::NoError) {
      QPixmap icon_pixmap;
      icon_pixmap.loadFromData(icon_data);
      output = QIcon(icon_pixmap);
      break;
    }
  }

  return network_result;
}

NetworkResult NetworkFactory::performNetworkOperation(const QString &url, int timeout, const QByteArray &input_data,
                                         const QString &input_content_type, QByteArray &output,
                                         QNetworkAccessManager::Operation operation, bool protected_contents,
                                         const QString &username, const QString &password, bool set_basic_header) {
  Downloader downloader;
  QEventLoop loop;
  NetworkResult result;

  QString str(input_data);

  downloader.appendRawHeader("Content-Type", input_content_type.toLocal8Bit());

  if (set_basic_header) {
    QString basic_value = username + ":" + password;
    QString header_value = QString("Basic ") + QString(basic_value.toUtf8().toBase64());

    downloader.appendRawHeader("Authorization", header_value.toLocal8Bit());
  }

  // We need to quit event loop when the download finishes.
  QObject::connect(&downloader, SIGNAL(completed(QNetworkReply::NetworkError)), &loop, SLOT(quit()));

  downloader.manipulateData(url, operation, input_data, timeout, protected_contents, username, password);
  loop.exec();
  output = downloader.lastOutputData();
  result.first = downloader.lastOutputError();
  result.second = downloader.lastContentType();

  return result;
}

NetworkResult NetworkFactory::downloadFeedFile(const QString &url, int timeout,
                                               QByteArray &output, bool protected_contents,
                                               const QString &username, const QString &password) {
  // Here, we want to achieve "synchronous" approach because we want synchronout download API for
  // some use-cases too.
  Downloader downloader;
  QEventLoop loop;
  NetworkResult result;

  downloader.appendRawHeader("Accept", ACCEPT_HEADER_FOR_FEED_DOWNLOADER);

  // We need to quit event loop when the download finishes.
  QObject::connect(&downloader, SIGNAL(completed(QNetworkReply::NetworkError)), &loop, SLOT(quit()));

  downloader.downloadFile(url, timeout, protected_contents, username, password);
  loop.exec();
  output = downloader.lastOutputData();
  result.first = downloader.lastOutputError();
  result.second = downloader.lastContentType();

  return result;
}