Implement gateway for adding new torrents

PR #19355.

src/gui/guiaddtorrentmanager.cpp

@@ -0,0 +1,200 @@
+/*
+ * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2015-2023  Vladimir Golovnev <glassez@yandex.ru>
+ * Copyright (C) 2006  Christophe Dumez <chris@qbittorrent.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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ */
+
+#include "guiaddtorrentmanager.h"
+
+#include "base/bittorrent/session.h"
+#include "base/bittorrent/torrentdescriptor.h"
+#include "base/logger.h"
+#include "base/net/downloadmanager.h"
+#include "base/preferences.h"
+#include "base/torrentfileguard.h"
+#include "addnewtorrentdialog.h"
+#include "interfaces/iguiapplication.h"
+#include "mainwindow.h"
+#include "raisedmessagebox.h"
+
+GUIAddTorrentManager::GUIAddTorrentManager(IGUIApplication *app, BitTorrent::Session *session, QObject *parent)
+    : GUIApplicationComponent(app, session, parent)
+{
+    connect(btSession(), &BitTorrent::Session::metadataDownloaded, this, &GUIAddTorrentManager::onMetadataDownloaded);
+}
+
+bool GUIAddTorrentManager::addTorrent(const QString &source, const BitTorrent::AddTorrentParams &params, const AddTorrentOption option)
+{
+    // `source`: .torrent file path,  magnet URI or URL
+
+    if (source.isEmpty())
+        return false;
+
+    const auto *pref = Preferences::instance();
+
+    if ((option == AddTorrentOption::SkipDialog)
+            || ((option == AddTorrentOption::Default) && !pref->isAddNewTorrentDialogEnabled()))
+    {
+        return AddTorrentManager::addTorrent(source, params);
+    }
+
+    if (Net::DownloadManager::hasSupportedScheme(source))
+    {
+        LogMsg(tr("Downloading torrent... Source: \"%1\"").arg(source));
+        // Launch downloader
+        Net::DownloadManager::instance()->download(Net::DownloadRequest(source).limit(pref->getTorrentFileSizeLimit())
+                , pref->useProxyForGeneralPurposes(), this, &GUIAddTorrentManager::onDownloadFinished);
+        m_downloadedTorrents[source] = params;
+
+        return true;
+    }
+
+    if (const auto parseResult = BitTorrent::TorrentDescriptor::parse(source))
+    {
+        return processTorrent(source, parseResult.value(), params);
+    }
+    else if (source.startsWith(u"magnet:", Qt::CaseInsensitive))
+    {
+        handleAddTorrentFailed(source, parseResult.error());
+        return false;
+    }
+
+    const Path decodedPath {source.startsWith(u"file://", Qt::CaseInsensitive)
+            ? QUrl::fromEncoded(source.toLocal8Bit()).toLocalFile() : source};
+    auto torrentFileGuard = std::make_shared<TorrentFileGuard>(decodedPath);
+    if (const auto loadResult = BitTorrent::TorrentDescriptor::loadFromFile(decodedPath))
+    {
+        const BitTorrent::TorrentDescriptor &torrentDescriptor = loadResult.value();
+        const bool isProcessing = processTorrent(source, torrentDescriptor, params);
+        if (isProcessing)
+            setTorrentFileGuard(source, torrentFileGuard);
+        return isProcessing;
+    }
+    else
+    {
+        handleAddTorrentFailed(decodedPath.toString(), loadResult.error());
+        return false;
+    }
+
+    return false;
+}
+
+void GUIAddTorrentManager::onDownloadFinished(const Net::DownloadResult &result)
+{
+    const QString &source = result.url;
+    const BitTorrent::AddTorrentParams addTorrentParams = m_downloadedTorrents.take(source);
+
+    switch (result.status)
+    {
+    case Net::DownloadStatus::Success:
+        if (const auto loadResult = BitTorrent::TorrentDescriptor::load(result.data))
+            processTorrent(source, loadResult.value(), addTorrentParams);
+        else
+            handleAddTorrentFailed(source, loadResult.error());
+        break;
+    case Net::DownloadStatus::RedirectedToMagnet:
+        if (const auto parseResult = BitTorrent::TorrentDescriptor::parse(result.magnetURI))
+            processTorrent(source, parseResult.value(), addTorrentParams);
+        else
+            handleAddTorrentFailed(source, parseResult.error());
+        break;
+    default:
+        handleAddTorrentFailed(source, result.errorString);
+    }
+}
+
+void GUIAddTorrentManager::onMetadataDownloaded(const BitTorrent::TorrentInfo &metadata)
+{
+    Q_ASSERT(metadata.isValid());
+    if (!metadata.isValid()) [[unlikely]]
+        return;
+
+    for (const auto &[infoHash, dialog] : m_dialogs.asKeyValueRange())
+    {
+        if (metadata.matchesInfoHash(infoHash))
+            dialog->updateMetadata(metadata);
+    }
+}
+
+bool GUIAddTorrentManager::processTorrent(const QString &source, const BitTorrent::TorrentDescriptor &torrentDescr, const BitTorrent::AddTorrentParams &params)
+{
+    const bool hasMetadata = torrentDescr.info().has_value();
+    const BitTorrent::InfoHash infoHash = torrentDescr.infoHash();
+
+    // Prevent showing the dialog if download is already present
+    if (BitTorrent::Torrent *torrent = btSession()->findTorrent(infoHash))
+    {
+        if (hasMetadata)
+        {
+            // Trying to set metadata to existing torrent in case if it has none
+            torrent->setMetadata(*torrentDescr.info());
+        }
+
+        if (torrent->isPrivate() || (hasMetadata && torrentDescr.info()->isPrivate()))
+        {
+            handleDuplicateTorrent(source, torrent, tr("Trackers cannot be merged because it is a private torrent"));
+        }
+        else
+        {
+            bool mergeTrackers = btSession()->isMergeTrackersEnabled();
+            if (Preferences::instance()->confirmMergeTrackers())
+            {
+                const QMessageBox::StandardButton btn = RaisedMessageBox::question(app()->mainWindow(), tr("Torrent is already present")
+                        , tr("Torrent '%1' is already in the transfer list. Do you want to merge trackers from new source?").arg(torrent->name())
+                        , (QMessageBox::Yes | QMessageBox::No), QMessageBox::Yes);
+                mergeTrackers = (btn == QMessageBox::Yes);
+            }
+
+            if (mergeTrackers)
+            {
+                torrent->addTrackers(torrentDescr.trackers());
+                torrent->addUrlSeeds(torrentDescr.urlSeeds());
+            }
+        }
+
+        return false;
+    }
+
+    if (!hasMetadata)
+        btSession()->downloadMetadata(torrentDescr);
+
+    auto *dlg = new AddNewTorrentDialog(torrentDescr, params, app()->mainWindow());
+    dlg->setAttribute(Qt::WA_DeleteOnClose);
+    m_dialogs[infoHash] = dlg;
+    connect(dlg, &QDialog::finished, this, [this, source, infoHash, dlg](int result)
+    {
+        if (dlg->isDoNotDeleteTorrentChecked())
+            releaseTorrentFileGuard(source);
+
+        if (result == QDialog::Accepted)
+            addTorrentToSession(source, dlg->torrentDescriptor(), dlg->addTorrentParams());
+
+        m_dialogs.remove(infoHash);
+    });
+    dlg->show();
+
+    return true;
+}