Revise 'Add trackers' dialog

* Now it allow user to add tracker to different tier.
* The downloaded trackers are now displayed as is (without modifying).
* Now the dialog remember dialog size and last used URL.

Closes #17692.

src/base/bittorrent/torrentimpl.cpp

@@ -540,6 +540,7 @@ void TorrentImpl::addTrackers(QVector<TrackerEntry> trackers)
     m_trackerEntries.append(trackers);
     std::sort(m_trackerEntries.begin(), m_trackerEntries.end()
         , [](const TrackerEntry &lhs, const TrackerEntry &rhs) { return lhs.tier < rhs.tier; });
+
     m_session->handleTorrentNeedSaveResumeData(this);
     m_session->handleTorrentTrackersAdded(this, trackers);
 }
@@ -561,6 +562,7 @@ void TorrentImpl::removeTrackers(const QStringList &trackers)
     if (!removedTrackers.isEmpty())
     {
         m_nativeHandle.replace_trackers(nativeTrackers);
+
         m_session->handleTorrentNeedSaveResumeData(this);
         m_session->handleTorrentTrackersRemoved(this, removedTrackers);
     }
@@ -579,12 +581,13 @@ void TorrentImpl::replaceTrackers(QVector<TrackerEntry> trackers)
         nativeTrackers.emplace_back(makeNativeAnnounceEntry(tracker.url, tracker.tier));
 
     m_nativeHandle.replace_trackers(nativeTrackers);
+    m_trackerEntries = trackers;
+
     // Clear the peer list if it's a private torrent since
     // we do not want to keep connecting with peers from old tracker.
     if (isPrivate())
         clearPeers();
 
-    m_trackerEntries = trackers;
     m_session->handleTorrentNeedSaveResumeData(this);
     m_session->handleTorrentTrackersChanged(this);
 }

src/base/bittorrent/trackerentry.cpp

@@ -28,6 +28,34 @@
 
 #include "trackerentry.h"
 
+#include <QList>
+#include <QVector>
+
+QVector<BitTorrent::TrackerEntry> BitTorrent::parseTrackerEntries(const QStringView str)
+{
+    const QList<QStringView> trackers = str.split(u'\n');  // keep the empty parts to track tracker tier
+
+    QVector<BitTorrent::TrackerEntry> entries;
+    entries.reserve(trackers.size());
+
+    int trackerTier = 0;
+    for (QStringView tracker : trackers)
+    {
+        tracker = tracker.trimmed();
+
+        if (tracker.isEmpty())
+        {
+            if (trackerTier < std::numeric_limits<decltype(trackerTier)>::max())  // prevent overflow
+                ++trackerTier;
+            continue;
+        }
+
+        entries.append({tracker.toString(), trackerTier});
+    }
+
+    return entries;
+}
+
 bool BitTorrent::operator==(const TrackerEntry &left, const TrackerEntry &right)
 {
     return (left.url == right.url);

src/base/bittorrent/trackerentry.h

@@ -30,10 +30,12 @@
 
 #include <libtorrent/socket.hpp>
 
+#include <QtContainerFwd>
 #include <QtGlobal>
 #include <QHash>
 #include <QMap>
 #include <QString>
+#include <QStringView>
 
 namespace BitTorrent
 {
@@ -74,6 +76,8 @@ namespace BitTorrent
         QString message {};
     };
 
+    QVector<TrackerEntry> parseTrackerEntries(QStringView str);
+
     bool operator==(const TrackerEntry &left, const TrackerEntry &right);
 #if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
     std::size_t qHash(const TrackerEntry &key, std::size_t seed = 0);