chatgui: remember last read message, restore scroll position, show unread count badge

Store read/scroll positions per channel via ui_state table (key-value).
Draw red +N badge on channel list items for unread messages.
Fix getMessages() to fetch last N messages (was fetching first N).

tools/chatgui/db/db_manager.cpp

@@ -116,6 +116,9 @@ QList<ChannelRow> DbManager::getChannels() const {
         list.append(r);
     }
     sqlite3_finalize(stmt);
+    for (auto& ch : list) {
+        ch.unreadCount = getUnreadCount(ch.channelId, ch.lastReadMsgId);
+    }
     return list;
 }
 
@@ -125,7 +128,7 @@ QList<MessageRow> DbManager::getMessages(const QString& chId, int limit) const {
     QList<MessageRow> list;
     QString sql = QStringLiteral(
         "SELECT id, node_id, data, timestamp, chain_hash, author_signature"
-        " FROM \"%1\" ORDER BY timestamp, author_signature ASC LIMIT ?").arg(msgTableName(chId));
+        " FROM \"%1\" ORDER BY timestamp DESC, author_signature DESC LIMIT ?").arg(msgTableName(chId));
     sqlite3_stmt* stmt = prepareOrNull(sql.toUtf8().constData());
     if (!stmt) return list;
     sqlite3_bind_int(stmt, 1, limit);
@@ -157,7 +160,7 @@ QList<MessageRow> DbManager::getMessages(const QString& chId, int limit) const {
         m.signature    = colBlob(stmt, 5);
         m.isOutgoing   = (m.authorNodeId == myId);
         m.isRead       = true;
-        list.append(m);
+        list.prepend(m);
     }
     sqlite3_finalize(stmt);
     return list;
@@ -383,6 +386,26 @@ int DbManager::getUiStateInt(const QString& key, int defaultVal) const {
     return ok ? v : defaultVal;
 }
 
+qint64 DbManager::getUiStateInt64(const QString& key, qint64 defaultVal) const {
+    QString val = getUiState(key);
+    if (val.isEmpty()) return defaultVal;
+    bool ok = false;
+    qint64 v = val.toLongLong(&ok);
+    return ok ? v : defaultVal;
+}
+
+int DbManager::getUnreadCount(const QString& channelId, qint64 lastReadMsgId) const {
+    QString sql = QStringLiteral(
+        "SELECT COUNT(*) FROM \"%1\" WHERE id > ?").arg(msgTableName(channelId));
+    sqlite3_stmt* stmt = prepareOrNull(sql.toUtf8().constData());
+    if (!stmt) return 0;
+    sqlite3_bind_int64(stmt, 1, lastReadMsgId);
+    int count = 0;
+    if (sqlite3_step(stmt) == SQLITE_ROW) count = sqlite3_column_int(stmt, 0);
+    sqlite3_finalize(stmt);
+    return count;
+}
+
 /* ── sync operations (read-only, for gui_bridge) ── */
 
 QByteArray DbManager::syncListChannels() const {

tools/chatgui/db/db_manager.h

@@ -21,6 +21,7 @@ struct ChannelRow {
     qint64     lastReadMsgId = 0;
     qint64     lastPosMsgId = 0;
     qint64     createdAt = 0;
+    int        unreadCount = 0;
 };
 
 struct MessageRow {
@@ -81,6 +82,10 @@ public:
 
     /* ── Каналы ── */
     QList<ChannelRow> getChannels() const;
+    int  getUnreadCount(const QString& channelId, qint64 lastReadMsgId) const;
+
+    /* ── UI state for channel read/scroll ── */
+    qint64 getUiStateInt64(const QString& key, qint64 defaultVal = 0) const;
 
     /* ── Сообщения (UI) ── */
     QList<MessageRow> getMessages(const QString& chId, int limit = 50) const;

tools/chatgui/src/channeldelegate.cpp

@@ -125,6 +125,28 @@ void ChannelDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
         }
     }
 
+    /* ── unread count badge (right of channel name) ── */
+    int unread = index.data(ChannelUnreadCountRole).toInt();
+    if (unread > 0) {
+        QString unreadText = unread > 99 ? QStringLiteral("99+") : QString::number(unread);
+        QFont badgeFont = option.font;
+        badgeFont.setBold(true);
+        badgeFont.setPixelSize(11);
+        QFontMetrics badgeFm(badgeFont);
+        int textW = badgeFm.horizontalAdvance(unreadText) + 8;
+        int badgeH = 18;
+        if (textW < badgeH) textW = badgeH;
+        QRect badgeRect(textRect.right() - textW, nameRect.top(),
+                        textW, badgeH);
+        painter->setRenderHint(QPainter::Antialiasing);
+        painter->setBrush(QColor("#E53935"));
+        painter->setPen(Qt::NoPen);
+        painter->drawRoundedRect(badgeRect, badgeH / 2, badgeH / 2);
+        painter->setFont(badgeFont);
+        painter->setPen(Qt::white);
+        painter->drawText(badgeRect, Qt::AlignCenter, unreadText);
+    }
+
     /* ── invite plus button (bottom-right) ── */
     QRect plusRect = inviteButtonRect(option.rect);
     bool plusHovered = index.data(ChannelInviteBtnHoveredRole).toInt() != 0;

tools/chatgui/src/channeldelegate.h

@@ -9,7 +9,8 @@ enum ChannelDataRole {
     ChannelChannelIdRole        = Qt::UserRole + 2,
     ChannelPeersOnlineRole      = Qt::UserRole + 3,  /* int: count of online peers */
     ChannelAutoConnectActiveRole = Qt::UserRole + 4, /* bool: 1 if auto-connect in progress */
-    ChannelInviteBtnHoveredRole  = Qt::UserRole + 5  /* bool: 1 when mouse hovers invite button */
+    ChannelInviteBtnHoveredRole  = Qt::UserRole + 5, /* bool: 1 when mouse hovers invite button */
+    ChannelUnreadCountRole      = Qt::UserRole + 6  /* int: unread message count, 0 if none */
 };
 
 class ChannelDelegate : public QStyledItemDelegate {

tools/chatgui/src/channellist.cpp

@@ -180,10 +180,11 @@ void ChannelList::loadChannels() {
             item->setData(ch.name,        ChannelNameRole);
             item->setData(ch.channelId,   ChannelChannelIdRole);
             item->setData(QString(),      ChannelLastMessageRole);
+            item->setData(ch.unreadCount, ChannelUnreadCountRole);
             item->setData(makeChannelIcon(colors[ci % 6], letter), ChannelIconRole);
             m_model->appendRow(item);
-            DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "ChannelList::loadChannels row=%d cid='%s' name='%s'",
-                       m_model->rowCount()-1, qPrintable(ch.channelId), qPrintable(ch.name));
+            DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "ChannelList::loadChannels row=%d cid='%s' name='%s' unread=%d",
+                       m_model->rowCount()-1, qPrintable(ch.channelId), qPrintable(ch.name), ch.unreadCount);
             ci++;
         }
     }
@@ -240,4 +241,24 @@ void ChannelList::setAutoConnectActive(bool active) {
     }
 }
 
+void ChannelList::setChannelUnreadCount(const QString& channelId, int count) {
+    for (int row = 0; row < m_model->rowCount(); row++) {
+        QStandardItem* item = m_model->item(row);
+        if (item && item->data(ChannelChannelIdRole).toString() == channelId) {
+            item->setData(count, ChannelUnreadCountRole);
+            emit m_model->dataChanged(m_model->index(row, 0), m_model->index(row, 0));
+            return;
+        }
+    }
+}
+
+int ChannelList::getChannelUnreadCount(const QString& channelId) const {
+    for (int row = 0; row < m_model->rowCount(); row++) {
+        QStandardItem* item = m_model->item(row);
+        if (item && item->data(ChannelChannelIdRole).toString() == channelId)
+            return item->data(ChannelUnreadCountRole).toInt();
+    }
+    return 0;
+}
+
 #include "channellist.moc"

tools/chatgui/src/channellist.h

@@ -16,6 +16,8 @@ public:
     void selectChannel(const QString& channelId);
     void setChannelPeersOnline(const QString& channelId, int count);
     void setAutoConnectActive(bool active);
+    void setChannelUnreadCount(const QString& channelId, int count);
+    int  getChannelUnreadCount(const QString& channelId) const;
 
 signals:
     void channelSelected(const QString& channelId);

tools/chatgui/src/mainwindow.cpp

@@ -212,6 +212,7 @@ void MainWindow::setupConnects() {
             this, [this](const QString& channelId) {
                 QSettings().setValue("last_channel_id", channelId);
                 m_currentChannelId = channelId;
+                m_channelList->setChannelUnreadCount(channelId, 0);
                 m_messageList->loadChannel(channelId);
                 m_accountList->setChannel(channelId);
                 QByteArray cidBA = channelId.toUtf8();
@@ -322,8 +323,15 @@ void MainWindow::showSettings() {
 void MainWindow::onMessageReceived(const char* ch_id) {
     DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "MainWindow: msg received ch=%s", ch_id);
     SoundManager::instance()->play("msg_incoming");
-    if (m_messageList)
-        m_messageList->refresh();
+    QString cid = QString::fromUtf8(ch_id);
+    if (m_messageList) {
+        if (cid == m_currentChannelId) {
+            m_messageList->refresh();
+        } else if (m_channelList) {
+            int unread = m_channelList->getChannelUnreadCount(cid) + 1;
+            m_channelList->setChannelUnreadCount(cid, unread);
+        }
+    }
 }
 
 void MainWindow::onMembersChanged(const char* ch_id) {

tools/chatgui/src/messagedelegate.h

@@ -12,6 +12,7 @@ enum MessageDataRole {
     MsgQuoteAuthorRole  = Qt::UserRole + 7,
     MsgQuoteTextRole    = Qt::UserRole + 8,
     MsgReactionsRole    = Qt::UserRole + 9,
+    MsgIdRole           = Qt::UserRole + 10,
 };
 
 class MessageDelegate : public QStyledItemDelegate {

tools/chatgui/src/messagelist.cpp

@@ -167,6 +167,11 @@ MessageList::MessageList(DbManager* db, QWidget *parent)
 
 void MessageList::loadChannel(const QString& channelId) {
     QWidget* prevFocus = QApplication::focusWidget();
+
+    /* Save state of current channel before switching */
+    if (!m_currentChannelId.isEmpty() && m_currentChannelId != channelId)
+        saveChannelState();
+
     m_model->clear();
     m_avatarCache.clear();
     m_currentChannelId = channelId;
@@ -174,9 +179,6 @@ void MessageList::loadChannel(const QString& channelId) {
 
     auto msgs = m_db->getMessages(channelId, 100);
 
-    struct ReactionKey { qint64 msgId; quint64 node; QString emoji; };
-    QHash<qint64, QHash<QString, QList<QColor>>> reactMap;
-
     for (const auto& m : msgs) {
         AccountRow acc = m_db->getAccount(m.authorNodeId);
         QString author  = m_db->getDisplayName(m.authorNodeId);
@@ -194,11 +196,12 @@ void MessageList::loadChannel(const QString& channelId) {
         auto *item = new QStandardItem();
         setMsg(item, author, QString::fromUtf8(m.data), time, avatar, false,
                false, QString(), QString(), reacts);
+        item->setData(m.id, MsgIdRole);
         m_model->appendRow(item);
     }
 
-    if (m_model->rowCount() > 0)
-        m_view->scrollToBottom();
+    restoreScrollPosition(channelId);
+
     if (prevFocus)
         prevFocus->setFocus();
     else
@@ -238,3 +241,60 @@ void MessageList::addMessage(const QString& channelId, quint64 authorNodeId,
 
     m_view->scrollToBottom();
 }
+
+void MessageList::saveChannelState() {
+    if (m_currentChannelId.isEmpty() || m_model->rowCount() == 0) return;
+
+    int vpHeight = m_view->viewport()->height();
+    QModelIndex topIdx = m_view->indexAt(QPoint(0, 0));
+    QModelIndex bottomIdx = m_view->indexAt(QPoint(0, vpHeight - 1));
+
+    qint64 lastReadMsgId = 0;
+    qint64 lastPosMsgId  = 0;
+
+    if (topIdx.isValid())
+        lastPosMsgId = topIdx.data(MsgIdRole).toLongLong();
+    if (bottomIdx.isValid())
+        lastReadMsgId = bottomIdx.data(MsgIdRole).toLongLong();
+    else if (m_model->rowCount() > 0)
+        lastReadMsgId = m_model->item(m_model->rowCount() - 1)->data(MsgIdRole).toLongLong();
+
+    if (lastReadMsgId == 0 && lastPosMsgId == 0) return;
+
+    QByteArray cid = m_currentChannelId.toUtf8();
+    auto saveKey = [&cid](const char* suffix, qint64 val) {
+        QByteArray key = "ch_" + cid + suffix;
+        QByteArray valStr = QByteArray::number(val);
+        size_t klen = key.size(), vlen = valStr.size();
+        size_t total = klen + 1 + vlen + 1;
+        if (total > 256) return;
+        void* arg = u_malloc(total);
+        memcpy(arg, key.constData(), klen + 1);
+        memcpy((char*)arg + klen + 1, valStr.constData(), vlen + 1);
+        gui_bridge_post_uasync_fn(chat_core_save_ui_state_trampoline, arg);
+    };
+
+    if (lastReadMsgId > 0) saveKey("_last_read", lastReadMsgId);
+    if (lastPosMsgId > 0)  saveKey("_last_pos", lastPosMsgId);
+}
+
+void MessageList::restoreScrollPosition(const QString& channelId) {
+    if (!m_db || m_model->rowCount() == 0) {
+        return;
+    }
+
+    qint64 lastPosMsgId = m_db->getUiStateInt64(
+        QStringLiteral("ch_%1_last_pos").arg(channelId), 0);
+
+    if (lastPosMsgId > 0) {
+        for (int row = 0; row < m_model->rowCount(); row++) {
+            QStandardItem* item = m_model->item(row);
+            if (item && item->data(MsgIdRole).toLongLong() == lastPosMsgId) {
+                m_view->scrollTo(m_model->index(row, 0), QAbstractItemView::PositionAtTop);
+                return;
+            }
+        }
+    }
+
+    m_view->scrollToBottom();
+}

tools/chatgui/src/messagelist.h

@@ -28,4 +28,7 @@ private:
     QString              m_currentChannelId;
     bool                 m_animHoverActive = false;
     QHash<quint64, QColor> m_avatarCache;
+
+    void saveChannelState();
+    void restoreScrollPosition(const QString& channelId);
 };