Add English and Russian ChatGUI interface translations

2026-10-05 16:55:43 +02:00
1 parent 972c6b7f0a
commit 27d93ecaf9
@@ -15,12 +15,47 @@ if(NOT Qt6_FOUND)
    set(QT_LIBS Qt5::Widgets Qt5::Network)
    set(QT_CORE  Qt5::Core)
    set(QT_TEST_LIB Qt5::Test)
+    set(QT_PACKAGE Qt5)
 else()
    set(QT_LIBS Qt6::Widgets Qt6::Network)
    set(QT_CORE  Qt6::Core)
    set(QT_TEST_LIB Qt6::Test)
+    set(QT_PACKAGE Qt6)
 endif()

+# Каталоги в ресурсах: перевод работает и в переносимой сборке без файлов рядом с exe.
+get_target_property(QT_QMAKE ${QT_PACKAGE}::qmake IMPORTED_LOCATION)
+execute_process(COMMAND "${QT_QMAKE}" -query QT_HOST_BINS
+    OUTPUT_VARIABLE QT_BINARY_DIR OUTPUT_STRIP_TRAILING_WHITESPACE RESULT_VARIABLE QT_BINARY_RESULT)
+if(NOT QT_BINARY_RESULT EQUAL 0)
+    message(FATAL_ERROR "Cannot query Qt host tools directory")
+endif()
+find_program(QT_GUI_LRELEASE NAMES lrelease HINTS "${QT_BINARY_DIR}" NO_DEFAULT_PATH)
+if(NOT QT_GUI_LRELEASE)
+    message(FATAL_ERROR "Qt lrelease is required to build GUI translations (install Qt Linguist tools)")
+endif()
+execute_process(COMMAND "${QT_QMAKE}" -query QT_INSTALL_TRANSLATIONS
+    OUTPUT_VARIABLE QT_TRANSLATIONS_DIR OUTPUT_STRIP_TRAILING_WHITESPACE RESULT_VARIABLE QT_TRANSLATIONS_RESULT)
+if(NOT QT_TRANSLATIONS_RESULT EQUAL 0)
+    message(FATAL_ERROR "Cannot query Qt translations directory")
+endif()
+set(QT_RUSSIAN_CATALOG "${QT_TRANSLATIONS_DIR}/qtbase_ru.qm")
+if(NOT EXISTS "${QT_RUSSIAN_CATALOG}")
+    message(FATAL_ERROR "Qt Russian translations missing: ${QT_RUSSIAN_CATALOG}")
+endif()
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/translations")
+set(GUI_QM_FILES)
+foreach(LANGUAGE en ru)
+    set(QM_FILE "${CMAKE_CURRENT_BINARY_DIR}/translations/chatgui_${LANGUAGE}.qm")
+    add_custom_command(OUTPUT "${QM_FILE}"
+        COMMAND "${QT_GUI_LRELEASE}" -nounfinished "${CMAKE_CURRENT_SOURCE_DIR}/translations/chatgui_${LANGUAGE}.ts" -qm "${QM_FILE}"
+        DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/translations/chatgui_${LANGUAGE}.ts"
+        VERBATIM)
+    list(APPEND GUI_QM_FILES "${QM_FILE}")
+endforeach()
+add_custom_target(chatgui_translations DEPENDS ${GUI_QM_FILES})
+configure_file(translations/translations.qrc.in "${CMAKE_CURRENT_BINARY_DIR}/translations.qrc" @ONLY)
+
 find_package(rlottie REQUIRED HINTS "${CMAKE_CURRENT_SOURCE_DIR}/rlottie_build")
 message(STATUS "rlottie package: ${rlottie_DIR}")
 find_package(ZLIB REQUIRED)
@@ -160,7 +195,9 @@ add_executable(vibechat
    db/db_manager.cpp
    ../../lib/sqlite3.c
    resources/chatgui.qrc
+    "${CMAKE_CURRENT_BINARY_DIR}/translations.qrc"
 )
+add_dependencies(vibechat chatgui_translations)

 target_include_directories(vibechat PRIVATE ${CMAKE_SOURCE_DIR}/../../lib ${CMAKE_SOURCE_DIR}/../../src ${CMAKE_SOURCE_DIR}/db ${CMAKE_SOURCE_DIR}/../../lib/libopus/include ${FFMPEG_INCLUDE_DIRS})
 target_compile_definitions(vibechat PRIVATE SQLITE_THREADSAFE=1 USE_SQLITE)
@@ -228,6 +265,14 @@ endif()

 enable_testing()

+add_executable(test_gui_language tests/test_gui_language.cpp src/networksettingspage.cpp
+    transport/node_config.cpp transport/config_updater.cpp "${CMAKE_CURRENT_BINARY_DIR}/translations.qrc")
+add_dependencies(test_gui_language chatgui_translations)
+target_compile_definitions(test_gui_language PRIVATE GUI_TS_DIR="${CMAKE_CURRENT_SOURCE_DIR}/translations")
+target_link_libraries(test_gui_language PRIVATE ${QT_LIBS} ${QT_TEST_LIB} OpenSSL::Crypto utun pthread)
+add_test(NAME test_gui_language COMMAND test_gui_language)
+set_tests_properties(test_gui_language PROPERTIES ENVIRONMENT "QT_QPA_PLATFORM=offscreen" TIMEOUT 30)
+
 add_executable(test_emoji_playback tests/test_emoji_playback.cpp src/animtimer.cpp src/lottieicon.cpp
    src/emojipanel.cpp src/emojitabbar.cpp src/emoji.cpp src/chatview.cpp)
 target_link_libraries(test_emoji_playback PRIVATE ${QT_LIBS} ${QT_TEST_LIB} rlottie::rlottie ZLIB::ZLIB utun)
@@ -55,10 +55,10 @@ install_deps() {
    echo "[deps] installing build dependencies..."
    if [ "$OS_ID" = linux ]; then
        sudo apt-get update
-        sudo apt-get install -y build-essential cmake qt6-base-dev librlottie-dev zlib1g-dev libssl-dev \
+        sudo apt-get install -y build-essential cmake qt6-base-dev qt6-tools-dev-tools qt6-translations-l10n librlottie-dev zlib1g-dev libssl-dev \
            libavcodec-dev libavformat-dev libavutil-dev libswscale-dev libswresample-dev
    else
-        sudo pkg install -y cmake qt6-base rlottie openssl ffmpeg
+        sudo pkg install -y cmake qt6-base qt6-tools qt6-translations rlottie openssl ffmpeg
    fi
 }

@@ -4,6 +4,18 @@

 Десктопный GUI-чат (Telegram-подобный) со встроенным P2P uTun-узлом. Приложение объединяет полнофункциональный интерфейс обмена сообщениями и децентрализованный транспортный слой в едином процессе. Рассчитан на работу без центральных серверов — вся маршрутизация, синхронизация и доставка сообщений идут напрямую между узлами по ETCP-протоколу.

+Язык интерфейса: русский или английский. По умолчанию используется первый поддерживаемый язык из списка языков интерфейса ОС;
+если поддерживаемых языков нет, используется английский. Выбор в «Настройки → Профиль → Язык интерфейса»:
+«Язык системы», English или Русский. Смена языка применяется после перезапуска, настройка хранится в `[gui] language=system|en|ru`.
+Региональный формат дат и чисел остаётся системным. Диагностические дампы ядра сохраняют исходные имена полей.
+
+Каталоги `translations/chatgui_en.ts` и `translations/chatgui_ru.ts` компилируются `lrelease` и встраиваются в приложение вместе
+с `qtbase_ru.qm` для стандартных виджетов Qt. Для сборки нужны инструменты Qt Linguist и пакет переводов Qt
+(Debian/Ubuntu: `qt6-tools-dev-tools`, `qt6-translations-l10n`; для Qt 5: `qttools5-dev-tools`, `qttranslations5-l10n`).
+После добавления строк обновить каталоги из `tools/chatgui`:
+`lupdate src -no-obsolete -locations relative -ts translations/chatgui_en.ts translations/chatgui_ru.ts`,
+заполнить новые переводы и пересобрать. Проверка: `ctest --test-dir build -R test_gui_language --output-on-failure`.
+
 ## 2. Архитектура

 ### 2.1. Уровни приложения
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "accountlist.h"
 #include "accountdelegate.h"
 #include "memberlistmodel.h"
@@ -57,10 +58,10 @@ QString AccountList::relativeTimeStr(qint64 timestamp) {
    if (timestamp <= 0) return "";
    qint64 diff = QDateTime::currentSecsSinceEpoch() - timestamp;
    if (diff < 0) diff = 0;
-    if (diff < 60)  return QString("%1s").arg(diff);
-    if (diff < 3600) return QString("%1m").arg(diff / 60);
-    if (diff < 86400) return QString("%1h").arg(diff / 3600);
-    return QString("%1d").arg(diff / 86400);
+    if (diff < 60)  return QCoreApplication::translate("ChatGui", "%1s").arg(diff);
+    if (diff < 3600) return QCoreApplication::translate("ChatGui", "%1m").arg(diff / 60);
+    if (diff < 86400) return QCoreApplication::translate("ChatGui", "%1h").arg(diff / 3600);
+    return QCoreApplication::translate("ChatGui", "%1d").arg(diff / 86400);
 }

 AccountList::AccountList(DbManager* db, QWidget *parent)
@@ -75,7 +76,7 @@ AccountList::AccountList(DbManager* db, QWidget *parent)
    layout->setContentsMargins(0, 0, 0, 0);
    layout->setSpacing(0);

-    m_header = new QLabel("Members", this);
+    m_header = new QLabel(QCoreApplication::translate("ChatGui", "Members"), this);
    m_header->setAlignment(Qt::AlignCenter);
    m_header->setStyleSheet("font-weight: bold; padding: 8px; background: palette(window);");
    layout->addWidget(m_header);
@@ -104,7 +105,7 @@ AccountList::AccountList(DbManager* db, QWidget *parent)
    detailLayout->setContentsMargins(0, 0, 0, 0);
    detailLayout->setSpacing(0);

-    m_detailHeader = new QLabel("Select a member", m_detailPanel);
+    m_detailHeader = new QLabel(QCoreApplication::translate("ChatGui", "Select a member"), m_detailPanel);
    m_detailHeader->setWordWrap(true);
    m_detailHeader->setStyleSheet("font-weight: bold; padding: 4px 8px; background: palette(window);");
    detailLayout->addWidget(m_detailHeader);
@@ -177,11 +178,11 @@ void AccountList::setChannel(const QString& channelId) {
    m_detailTimer->stop();
    m_linkTimer->stop();
    m_detailNodeId = 0;
-    m_detailHeader->setText("Select a member");
+    m_detailHeader->setText(QCoreApplication::translate("ChatGui", "Select a member"));
    m_detailText->clear();

-    m_header->setText(isOwner ? QString::fromUtf8("Members \xF0\x9F\x94\x91") : QStringLiteral("Members"));
-    m_header->setToolTip(isOwner ? QStringLiteral("Channel owner (has private key)") : QString());
+    m_header->setText(isOwner ? QCoreApplication::translate("ChatGui", "Members 🔑") : QCoreApplication::translate("ChatGui", "Members"));
+    m_header->setToolTip(isOwner ? QCoreApplication::translate("ChatGui", "Channel owner (has private key)") : QString());
 }

 void AccountList::refresh() { m_model->refresh(); }
@@ -371,9 +372,9 @@ void AccountList::updateDetailDisplay() {
    hdr.append(QString("<span style='color:%1;'>●</span> %2  %3")
        .arg(dotColor, m_detailName.toHtmlEscaped(), nodeHex));
    if (m_detailLastSeen > 0)
-        hdr.append(QString("seen %1").arg(relativeTimeStr(m_detailLastSeen)));
+        hdr.append(QCoreApplication::translate("ChatGui", "seen %1").arg(relativeTimeStr(m_detailLastSeen)));
    if (m_detailCreated > 0)
-        hdr.append(QString("created %1").arg(relativeTimeStr(m_detailCreated)));
+        hdr.append(QCoreApplication::translate("ChatGui", "created %1").arg(relativeTimeStr(m_detailCreated)));
    m_detailHeader->setText(hdr.join("  "));

    /* ── Body ── */
@@ -385,7 +386,7 @@ void AccountList::updateDetailDisplay() {
    };

    if (!m_detailAddrs.isEmpty()) {
-        lines.append("── Addresses ──");
+        lines.append(QCoreApplication::translate("ChatGui", "── Addresses ──"));
        for (const auto& a : m_detailAddrs) {
            lines.append(QString("  [sock%1] %2  %3  %4:%5  %6")
                .arg(a.socket_id)
@@ -398,7 +399,7 @@ void AccountList::updateDetailDisplay() {
    }

    if (isSelf) {
-        lines.append("── Listen ──");
+        lines.append(QCoreApplication::translate("ChatGui", "── Listen ──"));
        for (const auto& s : m_snapSocks) {
            const DetailAddress* a = nullptr;
            for (const auto& da : m_detailAddrs) {
@@ -413,7 +414,7 @@ void AccountList::updateDetailDisplay() {
        }
    } else {
        if (!m_snapLinks.isEmpty()) {
-            lines.append("── Connections ──");
+            lines.append(QCoreApplication::translate("ChatGui", "── Connections ──"));
            for (const auto& lk : m_snapLinks) {
                bool up = (lk.linkState == 3 && lk.linkStatus == 1);
                QString c = up ? "#4CAF50" : "#E53935";
@@ -482,15 +483,15 @@ void AccountList::onMemberContextMenu(const QPoint& pos) {
    QString name = m_model->data(index, Qt::DisplayRole).toString();

    QMenu menu(m_listView);
-    QAction* pmAction = menu.addAction(QString::fromUtf8("Написать сообщение"));
+    QAction* pmAction = menu.addAction(QCoreApplication::translate("ChatGui", "Send message"));
    if (nodeId == m_db->myNodeId()) pmAction->setEnabled(false);
-    QAction* callAction = menu.addAction(QString::fromUtf8("Позвонить"));
+    QAction* callAction = menu.addAction(QCoreApplication::translate("ChatGui", "Call peer"));
    if (nodeId == m_db->myNodeId() || !m_model->isOnlineAt(index.row())) callAction->setEnabled(false);
-    QAction* connectAction = menu.addAction("Connect");
+    QAction* connectAction = menu.addAction(QCoreApplication::translate("ChatGui", "Connect"));
    if (nodeId == m_db->myNodeId()) connectAction->setEnabled(false);
-    QAction* renameAction = menu.addAction("Rename");
+    QAction* renameAction = menu.addAction(QCoreApplication::translate("ChatGui", "Rename"));
    if (nodeId == m_db->myNodeId()) renameAction->setEnabled(false);
-    QAction* editAction = menu.addAction("Edit");
+    QAction* editAction = menu.addAction(QCoreApplication::translate("ChatGui", "Edit"));
    QAction* chosen = menu.exec(m_listView->viewport()->mapToGlobal(pos));

    if (chosen == pmAction) {
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "audiodevicesettingspage.h"
 #include "sound_manager.h"
 #include "audiorecorder.h"
@@ -33,14 +34,14 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    formLayout->setContentsMargins(0, 0, 0, 0);
    formLayout->setSpacing(10);

-    auto* outLabel = new QLabel("Playback device:", this);
+    auto* outLabel = new QLabel(QCoreApplication::translate("ChatGui", "Playback device:"), this);
    m_outputCombo = new QComboBox(this);
    m_outputCombo->setStyleSheet(
        "QComboBox { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 10px; font-size: 13px; background: palette(base); }");
    formLayout->addRow(outLabel, m_outputCombo);

-    auto* inLabel = new QLabel("Recording device:", this);
+    auto* inLabel = new QLabel(QCoreApplication::translate("ChatGui", "Recording device:"), this);
    m_inputCombo = new QComboBox(this);
    m_inputCombo->setStyleSheet(m_outputCombo->styleSheet());
    formLayout->addRow(inLabel, m_inputCombo);
@@ -54,7 +55,7 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    layout->addWidget(sep1);

    /* --- Microphone test --- */
-    auto* micLabel = new QLabel("Microphone test", this);
+    auto* micLabel = new QLabel(QCoreApplication::translate("ChatGui", "Microphone test"), this);
    micLabel->setStyleSheet("font-size: 13px; font-weight: bold;");
    layout->addWidget(micLabel);

@@ -67,7 +68,7 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    m_micLevelBar->setFixedHeight(16);
    micRow->addWidget(m_micLevelBar, 1);

-    m_testMicBtn = new QPushButton("Test Microphone", this);
+    m_testMicBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Test Microphone"), this);
    m_testMicBtn->setCheckable(true);
    m_testMicBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
@@ -84,11 +85,11 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    layout->addWidget(sep2);

    /* --- Speaker test --- */
-    auto* spkLabel = new QLabel("Speaker test", this);
+    auto* spkLabel = new QLabel(QCoreApplication::translate("ChatGui", "Speaker test"), this);
    spkLabel->setStyleSheet("font-size: 13px; font-weight: bold;");
    layout->addWidget(spkLabel);

-    m_testSpeakerBtn = new QPushButton("Test Speaker (440Hz)", this);
+    m_testSpeakerBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Test Speaker (440Hz)"), this);
    m_testSpeakerBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -103,14 +104,14 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    layout->addWidget(sep3);

    /* --- Codec quality --- */
-    auto* codecLabel = new QLabel("Voice codec quality", this);
+    auto* codecLabel = new QLabel(QCoreApplication::translate("ChatGui", "Voice codec quality"), this);
    codecLabel->setStyleSheet("font-size: 13px; font-weight: bold;");
    layout->addWidget(codecLabel);

    m_codecPresetCombo = new QComboBox(this);
-    m_codecPresetCombo->addItem("Low (16 kbps, fast)", 0);
-    m_codecPresetCombo->addItem("Standard (32 kbps)", 1);
-    m_codecPresetCombo->addItem("High (64 kbps, best)", 2);
+    m_codecPresetCombo->addItem(QCoreApplication::translate("ChatGui", "Low (16 kbps, fast)"), 0);
+    m_codecPresetCombo->addItem(QCoreApplication::translate("ChatGui", "Standard (32 kbps)"), 1);
+    m_codecPresetCombo->addItem(QCoreApplication::translate("ChatGui", "High (64 kbps, best)"), 2);
    m_codecPresetCombo->setStyleSheet(m_outputCombo->styleSheet());
    layout->addWidget(m_codecPresetCombo);

@@ -121,7 +122,7 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    layout->addWidget(sep5);

    /* --- Radio (PTT) Opus --- */
-    auto* radioLabel = new QLabel("Radio (PTT) — Opus", this);
+    auto* radioLabel = new QLabel(QCoreApplication::translate("ChatGui", "Radio (PTT) — Opus"), this);
    radioLabel->setStyleSheet("font-size: 13px; font-weight: bold;");
    layout->addWidget(radioLabel);

@@ -130,20 +131,20 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    radioForm->setSpacing(10);

    m_radioOpusModeCombo = new QComboBox(this);
-    m_radioOpusModeCombo->addItem("Voice (VOIP)", 0);
-    m_radioOpusModeCombo->addItem("Music (AUDIO)", 1);
+    m_radioOpusModeCombo->addItem(QCoreApplication::translate("ChatGui", "Voice (VOIP)"), 0);
+    m_radioOpusModeCombo->addItem(QCoreApplication::translate("ChatGui", "Music (AUDIO)"), 1);
    m_radioOpusModeCombo->setStyleSheet(m_outputCombo->styleSheet());
-    radioForm->addRow(new QLabel("Mode:", this), m_radioOpusModeCombo);
+    radioForm->addRow(new QLabel(QCoreApplication::translate("ChatGui", "Mode:"), this), m_radioOpusModeCombo);

    m_radioOpusBitrateCombo = new QComboBox(this);
    for (int br : {16, 32, 64, 96, 128})
-        m_radioOpusBitrateCombo->addItem(QString::number(br) + " kbps", br);
+        m_radioOpusBitrateCombo->addItem(QString::number(br) + QCoreApplication::translate("ChatGui", " kbps"), br);
    m_radioOpusBitrateCombo->setStyleSheet(m_outputCombo->styleSheet());
-    radioForm->addRow(new QLabel("Bitrate:", this), m_radioOpusBitrateCombo);
+    radioForm->addRow(new QLabel(QCoreApplication::translate("ChatGui", "Bitrate:"), this), m_radioOpusBitrateCombo);

    layout->addLayout(radioForm);

-    m_radioCaptureStereoCb = new QCheckBox("Capture stereo (playback is always stereo)", this);
+    m_radioCaptureStereoCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Capture stereo (playback is always stereo)"), this);
    m_radioCaptureStereoCb->setStyleSheet("font-size: 12px;");
    layout->addWidget(m_radioCaptureStereoCb);

@@ -159,9 +160,9 @@ AudioDeviceSettingsPage::AudioDeviceSettingsPage(DbManager* db, AudioRecorder* r
    m_jitterReserveSpin->setDecimals(1);
    m_jitterReserveSpin->setSingleStep(0.1);
    m_jitterReserveSpin->setValue(1.0);
-    m_jitterReserveSpin->setSuffix(" s");
-    m_jitterReserveSpin->setToolTip("Maximum adaptive jitter reserve for calls. Applies to the next call.");
-    callForm->addRow("Call: maximum jitter reserve", m_jitterReserveSpin);
+    m_jitterReserveSpin->setSuffix(QCoreApplication::translate("ChatGui", " s"));
+    m_jitterReserveSpin->setToolTip(QCoreApplication::translate("ChatGui", "Maximum adaptive jitter reserve for calls. Applies to the next call."));
+    callForm->addRow(QCoreApplication::translate("ChatGui", "Call: maximum jitter reserve"), m_jitterReserveSpin);
    layout->addLayout(callForm);

    buildCompressorUI(layout);
@@ -183,19 +184,19 @@ void AudioDeviceSettingsPage::loadFromDb() {

    /* Output devices */
    m_outputCombo->clear();
-    m_outputCombo->addItem("Default (auto)", QString());
+    m_outputCombo->addItem(QCoreApplication::translate("ChatGui", "Default (auto)"), QString());
    for (int i = 0; i < playbackDevs.size(); i++) {
        QString label = playbackDevs[i].name;
-        if (playbackDevs[i].isDefault) label += " (default)";
+        if (playbackDevs[i].isDefault) label += QCoreApplication::translate("ChatGui", " (default)");
        m_outputCombo->addItem(label, playbackDevs[i].id);
    }

    /* Input devices */
    m_inputCombo->clear();
-    m_inputCombo->addItem("Default (auto)", QString());
+    m_inputCombo->addItem(QCoreApplication::translate("ChatGui", "Default (auto)"), QString());
    for (int i = 0; i < captureDevs.size(); i++) {
        QString label = captureDevs[i].name;
-        if (captureDevs[i].isDefault) label += " (default)";
+        if (captureDevs[i].isDefault) label += QCoreApplication::translate("ChatGui", " (default)");
        m_inputCombo->addItem(label, captureDevs[i].id);
    }

@@ -366,11 +367,11 @@ void AudioDeviceSettingsPage::onTestMicToggled() {
        m_testRecorder->startRecording(true);
        m_micTestActive = true;
        m_levelTimer->start();
-        m_testMicBtn->setText("Stop Test");
+        m_testMicBtn->setText(QCoreApplication::translate("ChatGui", "Stop Test"));
        m_micLevelBar->setValue(0);
    } else {
        stopMicTest();
-        m_testMicBtn->setText("Test Microphone");
+        m_testMicBtn->setText(QCoreApplication::translate("ChatGui", "Test Microphone"));
    }
 }

@@ -415,15 +416,15 @@ void AudioDeviceSettingsPage::onTestSpeaker() {
 }

 void AudioDeviceSettingsPage::buildCompressorUI(QVBoxLayout* layout) {
-    auto* compLabel = new QLabel("Voice Compressor", this);
+    auto* compLabel = new QLabel(QCoreApplication::translate("ChatGui", "Voice Compressor"), this);
    compLabel->setStyleSheet("font-size: 13px; font-weight: bold;");
    layout->addWidget(compLabel);

-    m_compressorEnabledCb = new QCheckBox("Enable compressor (leveler/normalizer)", this);
+    m_compressorEnabledCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Enable compressor (leveler/normalizer)"), this);
    m_compressorEnabledCb->setStyleSheet("font-size: 12px;");
    layout->addWidget(m_compressorEnabledCb);

-    m_aecEnabledCb = new QCheckBox("Enable echo cancellation (AEC) in calls", this);
+    m_aecEnabledCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Enable echo cancellation (AEC) in calls"), this);
    m_aecEnabledCb->setStyleSheet("font-size: 12px;");
    layout->addWidget(m_aecEnabledCb);

@@ -432,7 +433,7 @@ void AudioDeviceSettingsPage::buildCompressorUI(QVBoxLayout* layout) {
        auto* row = new QHBoxLayout();
        row->setSpacing(6);
        auto* textLabel = new QLabel(name, this);
-        textLabel->setFixedWidth(180);
+        textLabel->setMinimumWidth(180);
        textLabel->setStyleSheet("font-size: 12px;");
        row->addWidget(textLabel);
        slider = new QSlider(Qt::Horizontal, this);
@@ -450,9 +451,9 @@ void AudioDeviceSettingsPage::buildCompressorUI(QVBoxLayout* layout) {
        layout->addLayout(row);
    };

-    makeSliderRow("Max gain:", m_compressorMaxGainSlider, m_compressorMaxGainLabel,
+    makeSliderRow(QCoreApplication::translate("ChatGui", "Max gain:"), m_compressorMaxGainSlider, m_compressorMaxGainLabel,
                   1, 50, 1);
-    makeSliderRow("Rise rate (x/sec):", m_compressorRiseRateSlider, m_compressorRiseRateLabel,
+    makeSliderRow(QCoreApplication::translate("ChatGui", "Rise rate (x/sec):"), m_compressorRiseRateSlider, m_compressorRiseRateLabel,
                   2, 10, 1);

    auto connectSlider = [this](QSlider* slider) {
@@ -464,7 +465,7 @@ void AudioDeviceSettingsPage::buildCompressorUI(QVBoxLayout* layout) {

 void AudioDeviceSettingsPage::updateCompressorLabels() {
    if (m_compressorMaxGainLabel)
-        m_compressorMaxGainLabel->setText(QString::number(m_compressorMaxGainSlider->value()) + " dB");
+        m_compressorMaxGainLabel->setText(QString::number(m_compressorMaxGainSlider->value()) + QCoreApplication::translate("ChatGui", " dB"));
    if (m_compressorRiseRateLabel) {
        int v = m_compressorRiseRateSlider->value();
        m_compressorRiseRateLabel->setText(QString::number(v) + "x");
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "callwindow.h"
 #include "../transport/gui_bridge.h"
 #include "call_audio_engine.h"
@@ -136,7 +137,7 @@ static QWidget* wrapWithCaption(QWidget* btn, const QString& caption, QLabel** c

 CallWindow::CallWindow(QWidget* parent)
    : QWidget(parent, Qt::Window) {
-    setWindowTitle(QStringLiteral("Звонок"));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Call"));
    setFixedSize(360, 480);
    setAttribute(Qt::WA_DeleteOnClose, false);

@@ -171,10 +172,10 @@ CallWindow::CallWindow(QWidget* parent)
    m_statsLabel->setStyleSheet("color: gray; font-size: 11px;");
    m_statsLabel->hide();

-    m_acceptBtn = makeRoundBtn(makeRoundIcon(QColor("#27ae60"), Glyph::Phone, 96), QStringLiteral("Принять"), this);
-    m_declineBtn = makeRoundBtn(makeRoundIcon(QColor("#e74c3c"), Glyph::PhoneDown, 96), QStringLiteral("Отклонить"), this);
-    m_hangupBtn = makeRoundBtn(makeRoundIcon(QColor("#e74c3c"), Glyph::PhoneDown, 96), QStringLiteral("Завершить"), this);
-    m_muteBtn = makeRoundBtn(makeRoundIcon(QColor("#7f8c8d"), Glyph::Mic, 96), QStringLiteral("Mute"), this);
+    m_acceptBtn = makeRoundBtn(makeRoundIcon(QColor("#27ae60"), Glyph::Phone, 96), QCoreApplication::translate("ChatGui", "Accept"), this);
+    m_declineBtn = makeRoundBtn(makeRoundIcon(QColor("#e74c3c"), Glyph::PhoneDown, 96), QCoreApplication::translate("ChatGui", "Decline"), this);
+    m_hangupBtn = makeRoundBtn(makeRoundIcon(QColor("#e74c3c"), Glyph::PhoneDown, 96), QCoreApplication::translate("ChatGui", "End call"), this);
+    m_muteBtn = makeRoundBtn(makeRoundIcon(QColor("#7f8c8d"), Glyph::Mic, 96), QCoreApplication::translate("ChatGui", "Mute"), this);
    m_muteBtn->setCheckable(true);

    m_deviceCombo = new QComboBox(this);
@@ -194,10 +195,10 @@ CallWindow::CallWindow(QWidget* parent)
    lay->addWidget(m_statsLabel);
    lay->addStretch(1);

-    m_acceptCell = wrapWithCaption(m_acceptBtn, QStringLiteral("Принять"));
-    m_declineCell = wrapWithCaption(m_declineBtn, QStringLiteral("Отклонить"));
-    m_hangupCell = wrapWithCaption(m_hangupBtn, QStringLiteral("Завершить"));
-    m_muteCell = wrapWithCaption(m_muteBtn, QStringLiteral("Mute"), &m_muteCaption);
+    m_acceptCell = wrapWithCaption(m_acceptBtn, QCoreApplication::translate("ChatGui", "Accept"));
+    m_declineCell = wrapWithCaption(m_declineBtn, QCoreApplication::translate("ChatGui", "Decline"));
+    m_hangupCell = wrapWithCaption(m_hangupBtn, QCoreApplication::translate("ChatGui", "End call"));
+    m_muteCell = wrapWithCaption(m_muteBtn, QCoreApplication::translate("ChatGui", "Mute"), &m_muteCaption);

    QHBoxLayout* btn = new QHBoxLayout();
    btn->setSpacing(10);
@@ -237,29 +238,29 @@ void CallWindow::setBgpPath(const QString& path) {
 }

 void CallWindow::setConnectionType(uint8_t type, quint64 nextHop) {
-    const QString names[] = { QStringLiteral("нет подключения"), QStringLiteral("прямое"),
-                              QStringLiteral("reverse"), QStringLiteral("indirect") };
-    m_connectionLabel->setText(QStringLiteral("Подключение: %1").arg(names[type <= 3 ? type : 0]));
-    m_connectionLabel->setToolTip(type == 3 ? QStringLiteral("Посредник: 0x%1").arg(nextHop, 16, 16, QChar('0')) : QString());
+    const QString names[] = { QCoreApplication::translate("ChatGui", "not connected"), QCoreApplication::translate("ChatGui", "direct"),
+                              QCoreApplication::translate("ChatGui", "reverse"), QCoreApplication::translate("ChatGui", "indirect") };
+    m_connectionLabel->setText(QCoreApplication::translate("ChatGui", "Connection: %1").arg(names[type <= 3 ? type : 0]));
+    m_connectionLabel->setToolTip(type == 3 ? QCoreApplication::translate("ChatGui", "Relay: 0x%1").arg(nextHop, 16, 16, QChar('0')) : QString());
 }

 void CallWindow::setState(State s) {
    m_state = s;
    switch (s) {
    case Outgoing:
-        m_statusLabel->setText(QStringLiteral("Пытаемся связаться…"));
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Connecting…"));
        m_durationLabel->hide();
        break;
    case Ringing:
-        m_statusLabel->setText(QStringLiteral("Звоним…"));
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Calling…"));
        m_durationLabel->hide();
        break;
    case Incoming:
-        m_statusLabel->setText(QStringLiteral("Входящий звонок…"));
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Incoming call…"));
        m_durationLabel->hide();
        break;
    case Active:
-        m_statusLabel->setText(QStringLiteral("Разговор"));
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "In call"));
        m_durationLabel->setText(QStringLiteral("00:00"));
        m_durationLabel->show();
        m_startMs = QDateTime::currentMSecsSinceEpoch();
@@ -269,7 +270,7 @@ void CallWindow::setState(State s) {
        break;
    case Ended:
        setConnectionType(0, 0);
-        m_statusLabel->setText(QStringLiteral("Завершён"));
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Ended"));
        m_durationTimer->stop();
        break;
    }
@@ -279,11 +280,11 @@ void CallWindow::setState(State s) {
 void CallWindow::populateDeviceCombo() {
    m_deviceCombo->blockSignals(true);
    m_deviceCombo->clear();
-    m_deviceCombo->addItem(QStringLiteral("Default (auto)"), QString());
+    m_deviceCombo->addItem(QCoreApplication::translate("ChatGui", "Default (auto)"), QString());
    const auto devs = SoundManager::enumeratePlaybackDevices();
    for (int i = 0; i < devs.size(); i++) {
        QString label = devs[i].name;
-        if (devs[i].isDefault) label += QStringLiteral(" (default)");
+        if (devs[i].isDefault) label += QCoreApplication::translate("ChatGui", " (default)");
        m_deviceCombo->addItem(label, devs[i].id);
    }
    QString cur = CallAudioEngine::instance()->playbackDevice();
@@ -328,7 +329,7 @@ void CallWindow::onMuteToggled(bool checked) {
    m_muteBtn->setIcon(makeRoundIcon(checked ? QColor("#e74c3c") : QColor("#7f8c8d"),
                                     checked ? Glyph::MicOff : Glyph::Mic, 96));
    if (m_muteCaption)
-        m_muteCaption->setText(checked ? QStringLiteral("Вкл. микрофон") : QStringLiteral("Mute"));
+        m_muteCaption->setText(checked ? QCoreApplication::translate("ChatGui", "Unmute") : QCoreApplication::translate("ChatGui", "Mute"));
 }

 void CallWindow::onDeviceChanged(int index) {
@@ -354,9 +355,9 @@ void CallWindow::updateDuration() {

 void CallWindow::setAudioStats(int rtt, int buffer, int tempo, int dropped, int underruns,
                              int minimum, int maximum, int reserve) {
-    m_statsLabel->setText(QStringLiteral("Буфер: %1 мс · Запас: %2 мс\n"
-        "За 10 с: минимум %3 · максимум %4 мс\n"
-        "Скорость: %5× · RTT: %6 мс\nПотери буфера: %7 · Недостачи: %8")
+    m_statsLabel->setText(QCoreApplication::translate("ChatGui",
+        "Buffer: %1 ms · Reserve: %2 ms\nOver 10 s: minimum %3 · maximum %4 ms\nSpeed: %5× · RTT: %6 "
+        "ms\nBuffer drops: %7 · Underruns: %8")
        .arg(buffer).arg(reserve).arg(minimum).arg(maximum)
        .arg(tempo / 100.0, 0, 'f', 2).arg(rtt).arg(dropped).arg(underruns));
    m_statsLabel->show();
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "channellist.h"
 #include "channeldelegate.h"
 #include "../db/db_manager.h"
@@ -146,7 +147,7 @@ ChannelList::ChannelList(DbManager* db, QWidget *parent)
    layout->setContentsMargins(0, 0, 0, 0);
    layout->setSpacing(0);

-    auto *header = new QLabel("Channels", this);
+    auto *header = new QLabel(QCoreApplication::translate("ChatGui", "Channels"), this);
    header->setAlignment(Qt::AlignCenter);
    header->setStyleSheet("font-weight: bold; padding: 8px; background: palette(window);");
    layout->addWidget(header);
@@ -167,7 +168,7 @@ ChannelList::ChannelList(DbManager* db, QWidget *parent)

    auto *gearBtn = new QPushButton(QString::fromUtf8("\xE2\x9A\x99"), footer);
    gearBtn->setFixedSize(28, 28);
-    gearBtn->setToolTip(QString::fromUtf8("Настройки"));
+    gearBtn->setToolTip(QCoreApplication::translate("ChatGui", "Settings"));
    gearBtn->setStyleSheet(
        "QPushButton { border: none; font-size: 18px; background: transparent; color: #666; }"
        "QPushButton:hover { color: #3390EC; background: rgba(51,144,236,20); border-radius: 14px; }");
@@ -177,7 +178,7 @@ ChannelList::ChannelList(DbManager* db, QWidget *parent)

    auto *monitorBtn = new QPushButton(QString::fromUtf8("\xF0\x9F\x94\x8D"), footer); /* 🔍 */
    monitorBtn->setFixedSize(28, 28);
-    monitorBtn->setToolTip(QString::fromUtf8("Connection Monitor"));
+    monitorBtn->setToolTip(QCoreApplication::translate("ChatGui", "Connection Monitor"));
    monitorBtn->setStyleSheet(
        "QPushButton { border: none; font-size: 16px; background: transparent; color: #666; }"
        "QPushButton:hover { color: #3390EC; background: rgba(51,144,236,20); border-radius: 14px; }");
@@ -186,9 +187,9 @@ ChannelList::ChannelList(DbManager* db, QWidget *parent)

    fl->addStretch();

-    auto *createBtn = new QPushButton("GRP", footer);
+    auto *createBtn = new QPushButton(QCoreApplication::translate("ChatGui", "GRP"), footer);
    createBtn->setFixedSize(36, 28);
-    createBtn->setToolTip(QString::fromUtf8("Создать группу"));
+    createBtn->setToolTip(QCoreApplication::translate("ChatGui", "Create group"));
    createBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 6px; font-size: 11px; font-weight: bold;"
        " color: white; background: #27AE60; }"
@@ -198,7 +199,7 @@ ChannelList::ChannelList(DbManager* db, QWidget *parent)

    auto *plusBtn = new QPushButton("+", footer);
    plusBtn->setFixedSize(28, 28);
-    plusBtn->setToolTip(QString::fromUtf8("Присоединиться"));
+    plusBtn->setToolTip(QCoreApplication::translate("ChatGui", "Join"));
    plusBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 14px; font-size: 18px; font-weight: bold;"
        " color: white; background: #3390EC; }"
@@ -294,7 +295,7 @@ void ChannelList::loadChannels() {
        auto dms = m_db->getDmConversations();
        if (!dms.isEmpty()) {
            auto *section = new QStandardItem();
-            section->setData(QStringLiteral("Личные"), ChannelNameRole);
+            section->setData(QCoreApplication::translate("ChatGui", "Direct messages"), ChannelNameRole);
            section->setData(true, ChannelIsSectionRole);
            section->setFlags(Qt::NoItemFlags);
            m_model->appendRow(section);
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "channelsettingsdialog.h"
 #include "../db/db_manager.h"
 #include "../transport/gui_bridge.h"
@@ -16,7 +17,7 @@ ChannelSettingsDialog::ChannelSettingsDialog(const QString& channelId, DbManager
    , m_channelId(channelId)
    , m_db(db)
 {
-    setWindowTitle(QStringLiteral("Channel Settings"));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Channel Settings"));
    setMinimumWidth(340);
    setModal(true);

@@ -24,7 +25,7 @@ ChannelSettingsDialog::ChannelSettingsDialog(const QString& channelId, DbManager
    layout->setContentsMargins(20, 16, 20, 16);
    layout->setSpacing(12);

-    auto* titleLabel = new QLabel(QStringLiteral("Settings for channel"), this);
+    auto* titleLabel = new QLabel(QCoreApplication::translate("ChatGui", "Settings for channel"), this);
    titleLabel->setStyleSheet("font-weight: bold; font-size: 14px;");
    layout->addWidget(titleLabel);

@@ -35,16 +36,18 @@ ChannelSettingsDialog::ChannelSettingsDialog(const QString& channelId, DbManager

    layout->addSpacing(8);

-    m_autoPlayVoice = new QCheckBox(QStringLiteral("Auto-play voice messages on receive"), this);
-    m_autoPlayVoice->setToolTip(QStringLiteral("Voice messages will play automatically when received. Multiple messages queue up and play sequentially without interrupting current playback."));
+    m_autoPlayVoice = new QCheckBox(QCoreApplication::translate("ChatGui", "Auto-play voice messages on receive"), this);
+    m_autoPlayVoice->setToolTip(QCoreApplication::translate("ChatGui",
+        "Voice messages will play automatically when received. Multiple messages queue up and play "
+        "sequentially without interrupting current playback."));
    layout->addWidget(m_autoPlayVoice);

-    m_soundOnMessage = new QCheckBox(QStringLiteral("Play sound on incoming message"), this);
-    m_soundOnMessage->setToolTip(QStringLiteral("Play a notification sound when a message arrives in this channel."));
+    m_soundOnMessage = new QCheckBox(QCoreApplication::translate("ChatGui", "Play sound on incoming message"), this);
+    m_soundOnMessage->setToolTip(QCoreApplication::translate("ChatGui", "Play a notification sound when a message arrives in this channel."));
    layout->addWidget(m_soundOnMessage);

-    m_pttMode = new QCheckBox(QStringLiteral("Push-To-Talk (PTT) mode"), this);
-    m_pttMode->setToolTip(QStringLiteral("Record voice messages with push-to-talk. (Coming soon)"));
+    m_pttMode = new QCheckBox(QCoreApplication::translate("ChatGui", "Push-To-Talk (PTT) mode"), this);
+    m_pttMode->setToolTip(QCoreApplication::translate("ChatGui", "Record voice messages with push-to-talk. (Coming soon)"));
    m_pttMode->setEnabled(false);
    layout->addWidget(m_pttMode);

@@ -54,8 +57,8 @@ ChannelSettingsDialog::ChannelSettingsDialog(const QString& channelId, DbManager
    btnLayout->setSpacing(8);
    btnLayout->addStretch();

-    auto* cancelBtn = new QPushButton(QStringLiteral("Cancel"), this);
-    cancelBtn->setFixedWidth(90);
+    auto* cancelBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Cancel"), this);
+    cancelBtn->setMinimumWidth(90);
    cancelBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -63,8 +66,8 @@ ChannelSettingsDialog::ChannelSettingsDialog(const QString& channelId, DbManager
    connect(cancelBtn, &QPushButton::clicked, this, &QDialog::reject);
    btnLayout->addWidget(cancelBtn);

-    auto* saveBtn = new QPushButton(QStringLiteral("Save"), this);
-    saveBtn->setFixedWidth(90);
+    auto* saveBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Save"), this);
+    saveBtn->setMinimumWidth(90);
    saveBtn->setDefault(true);
    saveBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 4px;"
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "chatview.h"
 #include "messagedelegate.h"
 #include "emoji.h"
@@ -44,7 +45,7 @@ ChatView::ChatView(QWidget *parent)
        "  background: rgba(90,90,90,220);"
        "}"
    );
-    m_scrollDownBtn->setToolTip(tr("Scroll to bottom"));
+    m_scrollDownBtn->setToolTip(QCoreApplication::translate("ChatGui", "Scroll to bottom"));
    m_scrollDownBtn->setVisible(false);

    connect(m_scrollDownBtn, &QPushButton::clicked, this, [this]() {
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 // connmonitorwindow.cpp — ETCP connection monitor (standalone, non-modal window)
 #include "connmonitorwindow.h"
 #include "../transport/gui_bridge.h"
@@ -31,7 +32,7 @@ static void connMetricsCb(const uint8_t* data, int len) {
 ConnMonitorWindow::ConnMonitorWindow(QWidget* parent)
    : QDialog(parent)
 {
-    setWindowTitle("Connection Monitor");
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Connection Monitor"));
    resize(900, 550);
    setAttribute(Qt::WA_DeleteOnClose);
    setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
@@ -40,7 +41,7 @@ ConnMonitorWindow::ConnMonitorWindow(QWidget* parent)
    mainLayout->setSpacing(4);
    mainLayout->setContentsMargins(8, 8, 8, 8);

-    auto* title = new QLabel("Active ETCP Connections (10 fps)", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "Active ETCP Connections (10 fps)"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    mainLayout->addWidget(title);

@@ -63,7 +64,7 @@ ConnMonitorWindow::ConnMonitorWindow(QWidget* parent)
    m_details->setStyleSheet(
        "QPlainTextEdit { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 8px; background: palette(base); }");
-    m_details->setPlaceholderText("Select a connection to view metrics");
+    m_details->setPlaceholderText(QCoreApplication::translate("ChatGui", "Select a connection to view metrics"));

    splitter->addWidget(m_connList);
    splitter->addWidget(m_details);
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "creategroupdialog.h"
 #include <QVBoxLayout>
 #include <QHBoxLayout>
@@ -8,16 +9,16 @@ CreateGroupDialog::CreateGroupDialog(QWidget* parent)
    : QDialog(parent)
    , m_nameEdit(new QLineEdit(this))
 {
-    setWindowTitle("Создать группу");
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Create group"));
    setMinimumWidth(350);
    setModal(true);

    auto* layout = new QVBoxLayout(this);

-    auto* nameLabel = new QLabel("Название группы:", this);
+    auto* nameLabel = new QLabel(QCoreApplication::translate("ChatGui", "Group name:"), this);
    layout->addWidget(nameLabel);

-    m_nameEdit->setPlaceholderText("Введите название...");
+    m_nameEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Enter a name..."));
    m_nameEdit->setMaxLength(128);
    layout->addWidget(m_nameEdit);

@@ -26,11 +27,11 @@ CreateGroupDialog::CreateGroupDialog(QWidget* parent)
    auto* btnLayout = new QHBoxLayout();
    btnLayout->addStretch();

-    auto* cancelBtn = new QPushButton("Отмена", this);
+    auto* cancelBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Cancel"), this);
    connect(cancelBtn, &QPushButton::clicked, this, &QDialog::reject);
    btnLayout->addWidget(cancelBtn);

-    auto* createBtn = new QPushButton("Создать", this);
+    auto* createBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Create"), this);
    createBtn->setDefault(true);
    connect(createBtn, &QPushButton::clicked, this, [this]() {
        if (m_nameEdit->text().trimmed().isEmpty()) {
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 // databasesettingspage.cpp — Database maintenance page in settings
 #include "databasesettingspage.h"
 #include "../db/db_manager.h"
@@ -17,7 +18,7 @@ DatabaseSettingsPage::DatabaseSettingsPage(DbManager* db, QWidget* parent)
    layout->setSpacing(10);
    layout->setContentsMargins(0, 0, 0, 0);

-    auto* title = new QLabel("Database Maintenance", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "Database Maintenance"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);

@@ -35,29 +36,29 @@ DatabaseSettingsPage::DatabaseSettingsPage(DbManager* db, QWidget* parent)
            QFileInfo fi(dbPath);
            if (fi.exists()) {
                qint64 sz = fi.size();
-                if (sz < 1024) dbSize = QString("%1 B").arg(sz);
-                else if (sz < 1024 * 1024) dbSize = QString("%1 KB").arg(sz / 1024);
-                else dbSize = QString("%1 MB").arg(sz / (1024.0 * 1024.0), 0, 'f', 2);
+                if (sz < 1024) dbSize = QCoreApplication::translate("ChatGui", "%1 B").arg(sz);
+                else if (sz < 1024 * 1024) dbSize = QCoreApplication::translate("ChatGui", "%1 KB").arg(sz / 1024);
+                else dbSize = QCoreApplication::translate("ChatGui", "%1 MB").arg(sz / (1024.0 * 1024.0), 0, 'f', 2);
            }
            QFileInfo walFi(dbPath + "-wal");
            if (walFi.exists()) {
                qint64 wsz = walFi.size();
-                if (wsz < 1024) walSize = QString("%1 B").arg(wsz);
-                else if (wsz < 1024 * 1024) walSize = QString("%1 KB").arg(wsz / 1024);
-                else walSize = QString("%1 MB").arg(wsz / (1024.0 * 1024.0), 0, 'f', 2);
+                if (wsz < 1024) walSize = QCoreApplication::translate("ChatGui", "%1 B").arg(wsz);
+                else if (wsz < 1024 * 1024) walSize = QCoreApplication::translate("ChatGui", "%1 KB").arg(wsz / 1024);
+                else walSize = QCoreApplication::translate("ChatGui", "%1 MB").arg(wsz / (1024.0 * 1024.0), 0, 'f', 2);
            } else {
-                walSize = "n/a";
+                walSize = QCoreApplication::translate("ChatGui", "n/a");
            }
        }
    }
    m_filePathLabel = new QLabel(dbPath, this);
    m_filePathLabel->setStyleSheet("font-size: 11px; color: gray;");
    m_filePathLabel->setTextInteractionFlags(Qt::TextSelectableByMouse);
-    infoLayout->addRow("File:", m_filePathLabel);
+    infoLayout->addRow(QCoreApplication::translate("ChatGui", "File:"), m_filePathLabel);

    m_fileSizeLabel = new QLabel(dbSize, this);
    m_fileSizeLabel->setStyleSheet("font-size: 11px;");
-    infoLayout->addRow("Size:", m_fileSizeLabel);
+    infoLayout->addRow(QCoreApplication::translate("ChatGui", "Size:"), m_fileSizeLabel);

    m_walSizeLabel = new QLabel(walSize, this);
    m_walSizeLabel->setStyleSheet("font-size: 11px;");
@@ -76,34 +77,34 @@ DatabaseSettingsPage::DatabaseSettingsPage(DbManager* db, QWidget* parent)
    btnLayout->setSpacing(6);

    auto* quickRow = new QHBoxLayout();
-    m_quickBtn = new QPushButton("Quick Check", this);
+    m_quickBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Quick Check"), this);
    m_quickBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 5px 14px; font-size: 12px; background: palette(button); }"
        "QPushButton:hover { background: palette(light); }");
    connect(m_quickBtn, &QPushButton::clicked, this, &DatabaseSettingsPage::onQuickCheck);
    quickRow->addWidget(m_quickBtn);
-    auto* quickDesc = new QLabel("Scans structure without verifying indexes (fast)", this);
+    auto* quickDesc = new QLabel(QCoreApplication::translate("ChatGui", "Scans structure without verifying indexes (fast)"), this);
    quickDesc->setStyleSheet("color: gray; font-size: 11px;");
    quickRow->addWidget(quickDesc, 1);
    btnLayout->addLayout(quickRow);

    auto* fullRow = new QHBoxLayout();
-    m_fullBtn = new QPushButton("Full Check", this);
+    m_fullBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Full Check"), this);
    m_fullBtn->setStyleSheet(m_quickBtn->styleSheet());
    connect(m_fullBtn, &QPushButton::clicked, this, &DatabaseSettingsPage::onFullCheck);
    fullRow->addWidget(m_fullBtn);
-    auto* fullDesc = new QLabel("Verifies all data structures and indexes (thorough)", this);
+    auto* fullDesc = new QLabel(QCoreApplication::translate("ChatGui", "Verifies all data structures and indexes (thorough)"), this);
    fullDesc->setStyleSheet("color: gray; font-size: 11px;");
    fullRow->addWidget(fullDesc, 1);
    btnLayout->addLayout(fullRow);

    auto* optRow = new QHBoxLayout();
-    m_optimizeBtn = new QPushButton("Optimize", this);
+    m_optimizeBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Optimize"), this);
    m_optimizeBtn->setStyleSheet(m_quickBtn->styleSheet());
    connect(m_optimizeBtn, &QPushButton::clicked, this, &DatabaseSettingsPage::onOptimize);
    optRow->addWidget(m_optimizeBtn);
-    auto* optDesc = new QLabel("Update query planner statistics for better performance", this);
+    auto* optDesc = new QLabel(QCoreApplication::translate("ChatGui", "Update query planner statistics for better performance"), this);
    optDesc->setStyleSheet("color: gray; font-size: 11px;");
    optRow->addWidget(optDesc, 1);
    btnLayout->addLayout(optRow);
@@ -123,13 +124,13 @@ DatabaseSettingsPage::DatabaseSettingsPage(DbManager* db, QWidget* parent)
        "QPlainTextEdit { font-family: monospace; font-size: 11px;"
        " background: palette(base); border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 4px; }");
-    m_resultText->setPlaceholderText("Run a check to see results...");
+    m_resultText->setPlaceholderText(QCoreApplication::translate("ChatGui", "Run a check to see results..."));
    layout->addWidget(m_resultText);

    layout->addStretch();

    if (!m_db || !m_db->m_db) {
-        m_statusLabel->setText("Database not connected");
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Database not connected"));
        m_statusLabel->setStyleSheet("font-size: 12px; font-weight: bold; color: red;");
        m_quickBtn->setEnabled(false);
        m_fullBtn->setEnabled(false);
@@ -140,7 +141,7 @@ DatabaseSettingsPage::DatabaseSettingsPage(DbManager* db, QWidget* parent)

 void DatabaseSettingsPage::refreshStatus() {
    if (!m_db || !m_db->m_db) {
-        m_statusLabel->setText("Database not connected");
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Database not connected"));
        m_statusLabel->setStyleSheet("font-size: 12px; font-weight: bold; color: red;");
        m_quickBtn->setEnabled(false);
        m_fullBtn->setEnabled(false);
@@ -157,16 +158,16 @@ void DatabaseSettingsPage::refreshStatus() {
        QFileInfo fi(dbPath);
        if (fi.exists()) {
            qint64 sz = fi.size();
-            if (sz < 1024) m_fileSizeLabel->setText(QString("%1 B").arg(sz));
-            else if (sz < 1024 * 1024) m_fileSizeLabel->setText(QString("%1 KB").arg(sz / 1024));
-            else m_fileSizeLabel->setText(QString("%1 MB").arg(sz / (1024.0 * 1024.0), 0, 'f', 2));
+            if (sz < 1024) m_fileSizeLabel->setText(QCoreApplication::translate("ChatGui", "%1 B").arg(sz));
+            else if (sz < 1024 * 1024) m_fileSizeLabel->setText(QCoreApplication::translate("ChatGui", "%1 KB").arg(sz / 1024));
+            else m_fileSizeLabel->setText(QCoreApplication::translate("ChatGui", "%1 MB").arg(sz / (1024.0 * 1024.0), 0, 'f', 2));
            QFileInfo walFi(dbPath + "-wal");
            if (walFi.exists()) {
                qint64 wsz = walFi.size();
-                if (wsz < 1024) m_walSizeLabel->setText(QString("%1 B").arg(wsz));
-                else if (wsz < 1024 * 1024) m_walSizeLabel->setText(QString("%1 KB").arg(wsz / 1024));
-                else m_walSizeLabel->setText(QString("%1 MB").arg(wsz / (1024.0 * 1024.0), 0, 'f', 2));
-            } else { m_walSizeLabel->setText("n/a"); }
+                if (wsz < 1024) m_walSizeLabel->setText(QCoreApplication::translate("ChatGui", "%1 B").arg(wsz));
+                else if (wsz < 1024 * 1024) m_walSizeLabel->setText(QCoreApplication::translate("ChatGui", "%1 KB").arg(wsz / 1024));
+                else m_walSizeLabel->setText(QCoreApplication::translate("ChatGui", "%1 MB").arg(wsz / (1024.0 * 1024.0), 0, 'f', 2));
+            } else { m_walSizeLabel->setText(QCoreApplication::translate("ChatGui", "n/a")); }
        }
    }
 }
@@ -176,47 +177,47 @@ void DatabaseSettingsPage::setBusy(bool busy) {
    m_fullBtn->setEnabled(!busy);
    m_optimizeBtn->setEnabled(!busy);
    if (busy) {
-        m_statusLabel->setText("Checking...");
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Checking..."));
        m_statusLabel->setStyleSheet("font-size: 12px; margin-top: 4px; color: gray;");
    }
 }

 void DatabaseSettingsPage::onQuickCheck() {
    if (!m_db || !m_db->m_db) {
-        m_statusLabel->setText("Database not open");
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Database not open"));
        m_statusLabel->setStyleSheet("font-size: 12px; color: red;");
        return;
    }
    setBusy(true);
    QTimer::singleShot(50, this, [this]() {
        IntegrityResult r = m_db->integrityCheckQuick();
-        showResult("Quick Check", r);
+        showResult(QCoreApplication::translate("ChatGui", "Quick Check"), r);
    });
 }

 void DatabaseSettingsPage::onFullCheck() {
    if (!m_db || !m_db->m_db) {
-        m_statusLabel->setText("Database not open");
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Database not open"));
        m_statusLabel->setStyleSheet("font-size: 12px; color: red;");
        return;
    }
    setBusy(true);
    QTimer::singleShot(50, this, [this]() {
        IntegrityResult r = m_db->integrityCheckFull();
-        showResult("Full Check", r);
+        showResult(QCoreApplication::translate("ChatGui", "Full Check"), r);
    });
 }

 void DatabaseSettingsPage::onOptimize() {
    if (!m_db || !m_db->m_db) {
-        m_statusLabel->setText("Database not open");
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "Database not open"));
        m_statusLabel->setStyleSheet("font-size: 12px; color: red;");
        return;
    }
    setBusy(true);
    QTimer::singleShot(50, this, [this]() {
        IntegrityResult r = m_db->integrityOptimize();
-        showResult("Optimize", r);
+        showResult(QCoreApplication::translate("ChatGui", "Optimize"), r);
    });
 }

@@ -226,11 +227,11 @@ void DatabaseSettingsPage::showResult(const QString& checkName, const IntegrityR
    m_optimizeBtn->setEnabled(true);

    if (result.ok) {
-        m_statusLabel->setText(QString("%1: OK  (%2 ms)")
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "%1: OK  (%2 ms)")
                               .arg(checkName).arg(result.elapsedMs));
        m_statusLabel->setStyleSheet("font-size: 12px; font-weight: bold; color: green;");
    } else {
-        m_statusLabel->setText(QString("%1: FAILED  (%2 ms)")
+        m_statusLabel->setText(QCoreApplication::translate("ChatGui", "%1: FAILED  (%2 ms)")
                               .arg(checkName).arg(result.elapsedMs));
        m_statusLabel->setStyleSheet("font-size: 12px; font-weight: bold; color: red;");
    }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "dminvitedialog.h"
 #include "debug_ui.h"
 #include "../db/db_manager.h"
@@ -18,28 +19,29 @@ extern "C" {

 DmInviteDialog::DmInviteDialog(DbManager* db, quint64 peer, const QString& name, const QString& source, QWidget* parent)
    : QDialog(parent), m_peer(peer), m_name(name), m_source(source) {
-    setWindowTitle(QStringLiteral("Пригласить в группу"));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Invite to group"));
    setMinimumWidth(400);
    auto* layout = new QVBoxLayout(this);
-    layout->addWidget(new QLabel(QStringLiteral("Получатель: %1").arg(name), this));
+    layout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Recipient: %1").arg(name), this));
    m_groups = new QComboBox(this);
    for (const auto& group : db->getChannels()) {
        if (db->isChannelMember(group.channelId, db->myNodeId())) m_groups->addItem(group.name, group.channelId);
    }
    m_groups->setCurrentIndex(-1);
-    m_groups->setPlaceholderText(QStringLiteral("Выберите группу"));
+    m_groups->setPlaceholderText(QCoreApplication::translate("ChatGui", "Select a group"));
    layout->addWidget(m_groups);
-    auto* expiry = new QLabel(QStringLiteral("Ссылка действует %1 минут с момента создания.\n"
-        "При поздней доставке PM потребуется новое приглашение.").arg(JOIN_KEY_TTL_SECONDS / 60), this);
+    auto* expiry = new QLabel(QCoreApplication::translate("ChatGui",
+        "The link expires %1 minutes after creation.\nIf the direct message arrives late, a new "
+        "invitation will be needed.").arg(JOIN_KEY_TTL_SECONDS / 60), this);
    expiry->setWordWrap(true);
    layout->addWidget(expiry);
    m_status = new QLabel(this);
    m_status->setWordWrap(true);
-    if (m_groups->count() == 0) m_status->setText(QStringLiteral("Нет групп для приглашения."));
+    if (m_groups->count() == 0) m_status->setText(QCoreApplication::translate("ChatGui", "No groups available to invite to."));
    layout->addWidget(m_status);
    auto* buttons = new QDialogButtonBox(QDialogButtonBox::Cancel, this);
-    buttons->button(QDialogButtonBox::Cancel)->setText(QStringLiteral("Отмена"));
-    m_send = buttons->addButton(QStringLiteral("Пригласить"), QDialogButtonBox::AcceptRole);
+    buttons->button(QDialogButtonBox::Cancel)->setText(QCoreApplication::translate("ChatGui", "Cancel"));
+    m_send = buttons->addButton(QCoreApplication::translate("ChatGui", "Invite"), QDialogButtonBox::AcceptRole);
    m_send->setEnabled(false);
    layout->addWidget(buttons);
    connect(buttons, &QDialogButtonBox::rejected, this, &QDialog::reject);
@@ -70,10 +72,11 @@ void DmInviteDialog::sendInvite() {
    if (m_pending || m_groups->currentIndex() < 0) return;
    if (!gui_bridge_is_uasync_ready() || !gui_bridge_get_inst()) {
        GUI_ERROR("invite PM: core unavailable");
-        m_status->setText(QStringLiteral("Ядро не запущено.")); return;
+        m_status->setText(QCoreApplication::translate("ChatGui", "The core is not running.")); return;
    }
    auto* req = (struct dm_invite_req*)u_calloc(1, sizeof(struct dm_invite_req));
-    if (!req) { GUI_ERROR("invite PM: request allocation failed"); m_status->setText(QStringLiteral("Недостаточно памяти.")); return; }
+    if (!req) { GUI_ERROR("invite PM: request allocation failed"); m_status->setText(QCoreApplication::translate("ChatGui",
+        "Not enough memory.")); return; }
    static uint64_t nextRequestId = 0;
    req->inst = gui_bridge_get_inst(); req->request_id = m_requestId = ++nextRequestId; req->peer_node_id = m_peer;
    req->channel_id = m_groups->currentData().toString().toULongLong();
@@ -81,7 +84,7 @@ void DmInviteDialog::sendInvite() {
    snprintf(req->peer_name, sizeof(req->peer_name), "%s", m_name.toUtf8().constData());
    m_pending = true;
    m_groups->setEnabled(false); m_send->setEnabled(false);
-    m_status->setText(QStringLiteral("Создание и отправка приглашения…"));
+    m_status->setText(QCoreApplication::translate("ChatGui", "Creating and sending invitation…"));
    gui_bridge_post_uasync_fn(dm_invite_trampoline, req);
 }

@@ -93,11 +96,11 @@ void DmInviteDialog::onResult(const uint8_t* data, int len) {
    if (!m_pending || request != m_requestId || peer != m_peer) return;
    m_pending = false;
    if (result == DM_INVITE_OK) { m_convId = QString::number(conv); accept(); return; }
-    const QString error = result == DM_INVITE_START_ERROR ? QStringLiteral("Не удалось создать личную беседу.")
-        : result == DM_INVITE_SEND_ERROR ? QStringLiteral("Не удалось отправить приглашение.")
-        : result == DM_INVITE_BUSY ? QStringLiteral("Другое приглашение ещё создаётся. Повторите попытку.")
-        : result == DM_INVITE_CANCELLED ? QStringLiteral("Создание приглашения отменено.")
-        : QStringLiteral("Не удалось создать приглашение. Проверьте подключение и повторите попытку.");
+    const QString error = result == DM_INVITE_START_ERROR ? QCoreApplication::translate("ChatGui", "Failed to create a direct conversation.")
+        : result == DM_INVITE_SEND_ERROR ? QCoreApplication::translate("ChatGui", "Failed to send the invitation.")
+        : result == DM_INVITE_BUSY ? QCoreApplication::translate("ChatGui", "Another invitation is still being created. Try again.")
+        : result == DM_INVITE_CANCELLED ? QCoreApplication::translate("ChatGui", "Invitation creation cancelled.")
+        : QCoreApplication::translate("ChatGui", "Failed to create an invitation. Check the connection and try again.");
    GUI_ERROR("invite PM dialog: failed request=%llu result=%d", (unsigned long long)request, result);
    m_status->setText(error); m_groups->setEnabled(true); m_send->setEnabled(m_groups->currentIndex() >= 0);
 }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "emoji.h"

 QHash<QString, QString> g_animatedEmojiMap;
@@ -133,10 +134,10 @@ static QVector<EmojiData> animations() {

 QVector<EmojiCategory> builtinEmojiSet() {
    return {
-        {"Smileys & People", smileys()},
-        {"Gestures",        gestures()},
-        {"Hearts & Symbols", hearts()},
-        {"Animations",       animations()},
+        {QCoreApplication::translate("ChatGui", "Smileys & People"), smileys()},
+        {QCoreApplication::translate("ChatGui", "Gestures"),        gestures()},
+        {QCoreApplication::translate("ChatGui", "Hearts & Symbols"), hearts()},
+        {QCoreApplication::translate("ChatGui", "Animations"),       animations()},
    };
 }

@@ -0,0 +1,15 @@
+/* Выбор языка интерфейса независимо от регионального формата дат и чисел. */
+#pragma once
+
+#include <QString>
+#include <QStringList>
+#include <QLocale>
+
+inline QString resolveGuiLanguage(const QString& preference, const QStringList& systemLanguages = QLocale::system().uiLanguages()) {
+    if (preference == QStringLiteral("en") || preference == QStringLiteral("ru")) return preference;
+    for (const QString& language : systemLanguages) {
+        const QString code = language.section('-', 0, 0).section('_', 0, 0).toLower();
+        if (code == QStringLiteral("en") || code == QStringLiteral("ru")) return code;
+    }
+    return QStringLiteral("en");
+}
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "imageviewer_window.h"
 #include "../../lib/debug_config.h"
 #include <QPainter>
@@ -34,14 +35,14 @@ static QPointF wheelPos(const QWheelEvent* e) {
 ImageViewerWindow::ImageViewerWindow(QWidget *parent)
    : QWidget(parent)
 {
-    setWindowTitle(QStringLiteral("Фото"));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Photo"));
    setAttribute(Qt::WA_DeleteOnClose, false);
    setMinimumSize(320, 240);
    resize(800, 600);
    setMouseTracking(true);

    m_closeBtn = new QPushButton(QStringLiteral("✕"), this);
-    m_closeBtn->setToolTip(QStringLiteral("Закрыть"));
+    m_closeBtn->setToolTip(QCoreApplication::translate("ChatGui", "Close"));
    m_closeBtn->setCursor(Qt::ArrowCursor);
    m_closeBtn->setStyleSheet(
        "QPushButton { background: rgba(0,0,0,0.5); color: white; border: none; "
@@ -56,7 +57,7 @@ ImageViewerWindow::ImageViewerWindow(QWidget *parent)
    m_closeFade = new QPropertyAnimation(m_closeEffect, "opacity", this);
    m_closeFade->setEasingCurve(QEasingCurve::InOutQuad);

-    m_hintLabel = new QLabel(QStringLiteral("Ctrl+колесо — зум"), this);
+    m_hintLabel = new QLabel(QCoreApplication::translate("ChatGui", "Ctrl+wheel — zoom"), this);
    m_hintLabel->setAlignment(Qt::AlignCenter);
    m_hintLabel->setAttribute(Qt::WA_TransparentForMouseEvents);
    m_hintLabel->setStyleSheet(
@@ -126,7 +127,7 @@ void ImageViewerWindow::paintEvent(QPaintEvent*) {

    if (m_image.isNull()) {
        p.setPen(QColor(150, 150, 150));
-        p.drawText(rect(), Qt::AlignCenter, QStringLiteral("Не удалось загрузить фото"));
+        p.drawText(rect(), Qt::AlignCenter, QCoreApplication::translate("ChatGui", "Failed to load photo"));
        return;
    }

@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "inputbar.h"
 #include "emojipanel.h"
 #include "audiorecorder.h"
@@ -61,13 +62,13 @@ static QWidget *wrapBottomBtn(QPushButton *btn, int pad) {
 }

 QString InputBar::formatFileSize(qint64 bytes) {
-    if (bytes < 1024) return QString("%1B").arg(bytes);
+    if (bytes < 1024) return QCoreApplication::translate("ChatGui", "%1B").arg(bytes);
    double kb = bytes / 1024.0;
-    if (kb < 1024.0) return QString("%1KB").arg(kb, 0, 'f', kb < 10.0 ? 1 : 0);
+    if (kb < 1024.0) return QCoreApplication::translate("ChatGui", "%1KB").arg(kb, 0, 'f', kb < 10.0 ? 1 : 0);
    double mb = kb / 1024.0;
-    if (mb < 1024.0) return QString("%1MB").arg(mb, 0, 'f', mb < 10.0 ? 1 : 0);
+    if (mb < 1024.0) return QCoreApplication::translate("ChatGui", "%1MB").arg(mb, 0, 'f', mb < 10.0 ? 1 : 0);
    double gb = mb / 1024.0;
-    return QString("%1GB").arg(gb, 0, 'f', 1);
+    return QCoreApplication::translate("ChatGui", "%1GB").arg(gb, 0, 'f', 1);
 }

 InputBar::InputBar(EmojiPanel *emojiPanel, AudioRecorder *recorder, QWidget *parent)
@@ -108,7 +109,7 @@ InputBar::InputBar(EmojiPanel *emojiPanel, AudioRecorder *recorder, QWidget *par
    layout->setSpacing(4);

    m_attachBtn = makeIconBtn(QIcon(":/icons/attach.png"),
-                              QString::fromUtf8("Прикрепить"), this);
+                              QCoreApplication::translate("ChatGui", "Attach"), this);
    connect(m_attachBtn, &QPushButton::clicked, this, &InputBar::onAttachClicked);
    layout->addWidget(wrapBottomBtn(m_attachBtn, 3), 0, Qt::AlignBottom);

@@ -126,15 +127,15 @@ InputBar::InputBar(EmojiPanel *emojiPanel, AudioRecorder *recorder, QWidget *par
    layout->addWidget(m_input, 1);

    m_emojiBtn = makeIconBtn(QIcon(":/icons/emoji.png"),
-                             QString::fromUtf8("Смайлики"), this);
+                             QCoreApplication::translate("ChatGui", "Emoji"), this);
    layout->addWidget(wrapBottomBtn(m_emojiBtn, 3), 0, Qt::AlignBottom);

    m_pttBtn = makeIconBtn(QIcon(":/icons/mic.png"),
-                           QString::fromUtf8("Голосовое сообщение (удерживайте)"), this);
+                           QCoreApplication::translate("ChatGui", "Voice message (hold)"), this);
    layout->addWidget(wrapBottomBtn(m_pttBtn, 3), 0, Qt::AlignBottom);

    auto *sendBtn = makeIconBtn(QIcon(":/icons/send.png"),
-                                QString::fromUtf8("Отправить"), this);
+                                QCoreApplication::translate("ChatGui", "Send"), this);
    sendBtn->setStyleSheet(sendBtn->styleSheet() +
        "QPushButton { border: 1px solid palette(highlight); }");
    layout->addWidget(sendBtn, 0, Qt::AlignBottom);
@@ -331,7 +332,7 @@ void InputBar::onPttReleased() {

 void InputBar::onAttachClicked() {
    if (m_channelIdForRecord.isEmpty()) return;
-    QString srcPath = QFileDialog::getOpenFileName(this, QString::fromUtf8("Прикрепить файл"));
+    QString srcPath = QFileDialog::getOpenFileName(this, QCoreApplication::translate("ChatGui", "Attach file"));
    if (srcPath.isEmpty()) return;

    QFileInfo fi(srcPath);
@@ -360,10 +361,10 @@ void InputBar::onAttachClicked() {
    bool asVideo = false;
    if (!asImage && QStringList{"mp4", "mov", "mkv", "avi", "webm", "m4v"}.contains(fi.suffix().toLower())) {
        QMessageBox box(this);
-        box.setWindowTitle(QString::fromUtf8("Отправить видео"));
-        box.setText(QString::fromUtf8("Файл содержит видео. Как отправить?"));
-        QPushButton *fileBtn = box.addButton(QString::fromUtf8("Как файл"), QMessageBox::AcceptRole);
-        QPushButton *videoBtn = box.addButton(QString::fromUtf8("Как видео"), QMessageBox::DestructiveRole);
+        box.setWindowTitle(QCoreApplication::translate("ChatGui", "Send video"));
+        box.setText(QCoreApplication::translate("ChatGui", "The file contains video. How would you like to send it?"));
+        QPushButton *fileBtn = box.addButton(QCoreApplication::translate("ChatGui", "As a file"), QMessageBox::AcceptRole);
+        QPushButton *videoBtn = box.addButton(QCoreApplication::translate("ChatGui", "As a video"), QMessageBox::DestructiveRole);
        box.exec();
        asVideo = (box.clickedButton() == videoBtn);
        if (!box.clickedButton() || (!asVideo && box.clickedButton() != fileBtn)) {
@@ -421,8 +422,8 @@ void InputBar::updatePreparation(const QString& target, const QByteArray& job, i

 void InputBar::showPreparation() {
    QString status;
-    if (!m_preparations.value(m_channelIdForRecord).isEmpty()) status = QString::fromUtf8("Подготовка медиа…");
-    else if (m_preparationErrors.contains(m_channelIdForRecord)) status = QString::fromUtf8("Не удалось подготовить вложение");
+    if (!m_preparations.value(m_channelIdForRecord).isEmpty()) status = QCoreApplication::translate("ChatGui", "Preparing media…");
+    else if (m_preparationErrors.contains(m_channelIdForRecord)) status = QCoreApplication::translate("ChatGui", "Failed to prepare attachment");
    m_preparationLabel->setText(status);
    m_preparationLabel->setVisible(!status.isEmpty());
 }
@@ -442,7 +443,7 @@ void InputBar::showRecordOverlay() {
        m_recordOverlay->setGeometry(m_input->geometry().adjusted(4, 4, -4, -4));
        m_recordOverlay->show();
        m_recordOverlay->raise();
-        m_recordLabel->setText(QString::fromUtf8("\xF0\x9F\x94\xB4 Recording 0:00"));
+        m_recordLabel->setText(QCoreApplication::translate("ChatGui", "🔴 Recording 0:00"));
        if (m_levelBar) m_levelBar->setValue(0);
    }
 }
@@ -454,7 +455,7 @@ void InputBar::hideRecordOverlay() {
 void InputBar::updateRecordingUI(int ms) {
    if (m_recordLabel) {
        int secs = ms / 1000;
-        m_recordLabel->setText(QString::fromUtf8("\xF0\x9F\x94\xB4 Recording %1:%2")
+        m_recordLabel->setText(QCoreApplication::translate("ChatGui", "🔴 Recording %1:%2")
            .arg(secs / 60).arg(secs % 60, 2, 10, QChar('0')));
    }
    if (m_levelBar && m_recorder) {
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "invite_link.h"
 #include "debug_ui.h"
 #include <QByteArray>
@@ -61,13 +62,13 @@ QString encodeInviteLink(uint64_t channelId, const QByteArray& pubkey,
 InviteData decodeInviteLink(const QString& link) {
    InviteData d;
    if (!link.startsWith(QLatin1String("utun://"))) {
-        d.error = QStringLiteral("invalid prefix (expected utun://)");
+        d.error = QCoreApplication::translate("ChatGui", "invalid prefix (expected utun://)");
        GUI_ERROR("decodeInviteLink: invalid prefix");
        return d;
    }
    QByteArray blob = QByteArray::fromBase64(link.mid(7).toLatin1());
    if (blob.isEmpty()) {
-        d.error = QStringLiteral("base64 decode failed");
+        d.error = QCoreApplication::translate("ChatGui", "base64 decode failed");
        GUI_ERROR("decodeInviteLink: base64 decode failed");
        return d;
    }
@@ -75,7 +76,7 @@ InviteData decodeInviteLink(const QString& link) {
    int len = blob.size();

    if (len < 11) {
-        d.error = QStringLiteral("blob too short (%1 bytes)").arg(len);
+        d.error = QCoreApplication::translate("ChatGui", "blob too short (%1 bytes)").arg(len);
        GUI_ERROR("decodeInviteLink: blob too short (%d bytes)", len);
        return d;
    }
@@ -83,7 +84,7 @@ InviteData decodeInviteLink(const QString& link) {

    uint8_t ver = data[off++];
    if (ver != INVITE_LINK_VERSION && ver != 0x02 && ver != 0x01) {
-        d.error = QStringLiteral("unsupported version 0x%1").arg(ver, 2, 16, QLatin1Char('0'));
+        d.error = QCoreApplication::translate("ChatGui", "unsupported version 0x%1").arg(ver, 2, 16, QLatin1Char('0'));
        GUI_ERROR("decodeInviteLink: unsupported version %d", ver);
        return d;
    }
@@ -91,13 +92,13 @@ InviteData decodeInviteLink(const QString& link) {
    /* v2/v3: password field before channel_id */
    if (ver == 0x02 || ver == INVITE_LINK_VERSION) {
        if (off >= len) {
-            d.error = QStringLiteral("truncated at pass_len");
+            d.error = QCoreApplication::translate("ChatGui", "truncated at pass_len");
            return d;
        }
        uint8_t plen = data[off++];
        if (plen > 0) {
            if (off + plen > len) {
-                d.error = QStringLiteral("truncated at password");
+                d.error = QCoreApplication::translate("ChatGui", "truncated at password");
                return d;
            }
            d.password = QString::fromUtf8(reinterpret_cast<const char*>(data + off), plen);
@@ -107,7 +108,7 @@ InviteData decodeInviteLink(const QString& link) {

    /* channel_id: uint64 big-endian */
    if (off + 8 > len) {
-        d.error = QStringLiteral("truncated at channel_id");
+        d.error = QCoreApplication::translate("ChatGui", "truncated at channel_id");
        GUI_ERROR("decodeInviteLink: truncated at channel_id");
        return d;
    }
@@ -118,7 +119,7 @@ InviteData decodeInviteLink(const QString& link) {

    /* join_key: uint64 big-endian */
    if (off + 8 > len) {
-        d.error = QStringLiteral("truncated at join_key");
+        d.error = QCoreApplication::translate("ChatGui", "truncated at join_key");
        GUI_ERROR("decodeInviteLink: truncated at join_key");
        return d;
    }
@@ -129,15 +130,15 @@ InviteData decodeInviteLink(const QString& link) {

    /* v3: reality-блок (node-global параметры) */
    if (ver == INVITE_LINK_VERSION) {
-        if (off >= len) { d.error = QStringLiteral("truncated at reality"); return d; }
+        if (off >= len) { d.error = QCoreApplication::translate("ChatGui", "truncated at reality"); return d; }
        if (data[off++] != 0) {
-            if (off + 8 + 32 + 3 + 1 > len) { d.error = QStringLiteral("truncated at reality params"); return d; }
+            if (off + 8 + 32 + 3 + 1 > len) { d.error = QCoreApplication::translate("ChatGui", "truncated at reality params"); return d; }
            d.reality.shortId = QByteArray(reinterpret_cast<const char*>(data + off), 8); off += 8;
            d.reality.serverPubkey = QByteArray(reinterpret_cast<const char*>(data + off), 32); off += 32;
            d.reality.version = QByteArray(reinterpret_cast<const char*>(data + off), 3); off += 3;
            uint8_t snlen = data[off++];
            if (snlen > INVITE_SNAME_MAX - 1) snlen = INVITE_SNAME_MAX - 1;
-            if (off + snlen > len) { d.error = QStringLiteral("truncated at reality server_name"); return d; }
+            if (off + snlen > len) { d.error = QCoreApplication::translate("ChatGui", "truncated at reality server_name"); return d; }
            d.reality.serverName = QString::fromUtf8(reinterpret_cast<const char*>(data + off), snlen);
            off += snlen;
            d.reality.has = true;
@@ -149,12 +150,12 @@ InviteData decodeInviteLink(const QString& link) {
        uint8_t header = data[off++];
        int cnt = (header & 0x03) + 1;
        if (cnt < 1 || cnt > 4) {
-            d.error = QStringLiteral("invalid addr count %1").arg(cnt);
+            d.error = QCoreApplication::translate("ChatGui", "invalid addr count %1").arg(cnt);
            GUI_ERROR("decodeInviteLink: invalid addr count %d", cnt);
            return d;
        }
        if (off + 32 > len) {
-            d.error = QStringLiteral("truncated at pubkey");
+            d.error = QCoreApplication::translate("ChatGui", "truncated at pubkey");
            GUI_ERROR("decodeInviteLink: truncated at pubkey");
            return d;
        }
@@ -168,7 +169,7 @@ InviteData decodeInviteLink(const QString& link) {
            bool isV6 = header & (1 << (2 + j));
            int ipLen = isV6 ? 16 : 4;
            if (off + 2 + ipLen + 2 > len) {
-                d.error = QStringLiteral("truncated at addr %1 of block").arg(j);
+                d.error = QCoreApplication::translate("ChatGui", "truncated at addr %1 of block").arg(j);
                GUI_ERROR("decodeInviteLink: truncated at addr %d of block", j);
                return d;
            }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "inviteby.h"
 #include "invite_link.h"
 #include "debug_ui.h"
@@ -21,14 +22,14 @@ extern "C" {
 InviteByLinkDialog::InviteByLinkDialog(const QString& channelId, UtunNode* node, QWidget* parent)
    : QDialog(parent), m_channelId(channelId), m_node(node)
 {
-    setWindowTitle(QString::fromUtf8("Пригласить в канал %1").arg(channelId));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Invite to channel %1").arg(channelId));
    setMinimumWidth(420);
    setModal(true);

    auto *layout = new QVBoxLayout(this);
    layout->setSpacing(12);

-    auto *title = new QLabel(QString::fromUtf8("Вставьте utun:// ссылку приглашаемого узла:"), this);
+    auto *title = new QLabel(QCoreApplication::translate("ChatGui", "Paste the invited node's utun:// link:"), this);
    title->setStyleSheet("font-weight: bold; font-size: 12px;");
    layout->addWidget(title);

@@ -46,7 +47,7 @@ InviteByLinkDialog::InviteByLinkDialog(const QString& channelId, UtunNode* node,

    auto *btnLayout = new QHBoxLayout();
    btnLayout->addStretch();
-    m_inviteSendBtn = new QPushButton(QString::fromUtf8("Пригласить"), this);
+    m_inviteSendBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Invite"), this);
    m_inviteSendBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 4px;"
        " padding: 5px 14px; font-size: 12px; font-weight: bold;"
@@ -83,14 +84,14 @@ void InviteByLinkDialog::onInviteLinkTextChanged() {
    }
    if (!link.startsWith(QLatin1String("utun://"))) {
        m_inviteStatusLabel->setStyleSheet("color: gray; font-size: 11px; padding: 2px 0;");
-        m_inviteStatusLabel->setText(QString::fromUtf8("Ожидается utun:// ссылка..."));
+        m_inviteStatusLabel->setText(QCoreApplication::translate("ChatGui", "Expected a utun:// link..."));
        return;
    }

    InviteData d = decodeInviteLink(link);
    if (!d.error.isEmpty()) {
        m_inviteStatusLabel->setStyleSheet("color: gray; font-size: 11px; padding: 2px 0;");
-        m_inviteStatusLabel->setText(QString::fromUtf8("Неверная ссылка: ") + d.error);
+        m_inviteStatusLabel->setText(QCoreApplication::translate("ChatGui", "Invalid link: ") + d.error);
        return;
    }

@@ -112,9 +113,9 @@ void InviteByLinkDialog::onInviteLinkTextChanged() {
                QString::fromLatin1(d.addrs[i].address.left(4).toHex())).arg(d.addrs[i].port);
        }
    }
-    if (d.addrs.size() > 3) addrInfo += QString(" +%1 more").arg(d.addrs.size() - 3);
+    if (d.addrs.size() > 3) addrInfo += QCoreApplication::translate("ChatGui", " +%1 more").arg(d.addrs.size() - 3);

-    QString diag = QString::fromUtf8("Ссылка: узел 0x%1 ключ %2, %3 адр. (%4)\nПриглашение в канал: %5")
+    QString diag = QCoreApplication::translate("ChatGui", "Link: node 0x%1 key %2, %3 addresses (%4)\nInvitation to channel: %5")
        .arg(targetNodeId, 16, 16, QChar('0'))
        .arg(pkShort)
        .arg(d.addrs.size())
@@ -123,7 +124,7 @@ void InviteByLinkDialog::onInviteLinkTextChanged() {

    if (myNodeId != 0 && myNodeId == targetNodeId) {
        m_inviteStatusLabel->setStyleSheet("color: #E67E22; font-size: 11px; padding: 2px 0;");
-        m_inviteStatusLabel->setText(diag + QString::fromUtf8(" ⚠ Это ваша собственная ссылка"));
+        m_inviteStatusLabel->setText(diag + QCoreApplication::translate("ChatGui", " ⚠ This is your own link"));
    } else {
        m_inviteStatusLabel->setStyleSheet("color: gray; font-size: 11px; padding: 2px 0;");
        m_inviteStatusLabel->setText(diag);
@@ -142,21 +143,21 @@ void InviteByLinkDialog::onSendInvite() {
    if (m_inviteSending) return;
    QString link = m_inviteLinkEdit->text().trimmed();
    if (link.isEmpty()) {
-        setInviteStatus(QString::fromUtf8("Вставьте utun:// ссылку узла."), true);
+        setInviteStatus(QCoreApplication::translate("ChatGui", "Paste the node's utun:// link."), true);
        return;
    }

    InviteData d = decodeInviteLink(link);
    if (!d.error.isEmpty()) {
-        setInviteStatus(QString::fromUtf8("Неверная ссылка: ") + d.error, true);
+        setInviteStatus(QCoreApplication::translate("ChatGui", "Invalid link: ") + d.error, true);
        return;
    }
    if (d.pubkey.size() != 32) {
-        setInviteStatus(QString::fromUtf8("Pubkey не 32 байта."), true);
+        setInviteStatus(QCoreApplication::translate("ChatGui", "The public key must be 32 bytes."), true);
        return;
    }
    if (d.addrs.isEmpty()) {
-        setInviteStatus(QString::fromUtf8("Нет адресов."), true);
+        setInviteStatus(QCoreApplication::translate("ChatGui", "No addresses."), true);
        return;
    }

@@ -166,7 +167,7 @@ void InviteByLinkDialog::onSendInvite() {
        uint64_t myNodeId = m_node ? m_node->nodeIdHex().toULongLong(nullptr, 16) : 0;
        if (myNodeId != 0 && myNodeId == targetNodeId) {
            GUI_WARN("invite_by_link: self-invite rejected — link contains own pubkey, node=0x%016llx", (unsigned long long)myNodeId);
-            setInviteStatus(QString::fromUtf8("Ошибка: это ваша собственная ссылка (нельзя пригласить себя)"), true);
+            setInviteStatus(QCoreApplication::translate("ChatGui", "Error: this is your own link (you cannot invite yourself)"), true);
            return;
        }
    }
@@ -186,27 +187,27 @@ void InviteByLinkDialog::onSendInvite() {
        (const uint8_t*)d.pubkey.constData(),
        (const uint8_t*)addrsBuf.constData(), d.addrs.size(), addrsBuf.size());

-    setInviteStatus(QString::fromUtf8("Приглашение отправлено, ожидание ответа..."));
+    setInviteStatus(QCoreApplication::translate("ChatGui", "Invitation sent, waiting for a response..."));
 }

 void InviteByLinkDialog::onConnectResult(uint64_t nodeId, uint64_t channelId, int result) {
    if (!m_inviteSending || nodeId != m_inviteTargetNodeId) return;

    if (result == 0) {
-        setInviteStatus(QString::fromUtf8("Узел присоединился к каналу."), false);
+        setInviteStatus(QCoreApplication::translate("ChatGui", "The node has joined the channel."), false);
        QTimer::singleShot(400, this, &QDialog::accept);
    } else {
        m_inviteSending = false;
        m_inviteSendBtn->setEnabled(true);
        m_inviteSendBtn->setFocus();

-        const char* errMsg = "Неизвестная ошибка.";
+        QString errMsg = QCoreApplication::translate("ChatGui", "Unknown error.");
        switch (result) {
-            case -1: errMsg = "Канал не найден."; break;
-            case  2: errMsg = "Таймаут — узел не ответил."; break;
-            case -7: errMsg = "Узел не инициализирован."; break;
+            case -1: errMsg = QCoreApplication::translate("ChatGui", "Channel not found."); break;
+            case  2: errMsg = QCoreApplication::translate("ChatGui", "Timed out — the node did not respond."); break;
+            case -7: errMsg = QCoreApplication::translate("ChatGui", "Node not initialized."); break;
            default: break;
        }
-        setInviteStatus(QString::fromUtf8("Ошибка: %1").arg(QString::fromUtf8(errMsg)), true);
+        setInviteStatus(QCoreApplication::translate("ChatGui", "Error: %1").arg(errMsg), true);
    }
 }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "invitedialog.h"
 #include "qrcode_utils.h"
 #include "../db/db_manager.h"
@@ -26,17 +27,18 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW
    , m_channelId(channelId)
    , m_db(db)
 {
-    setWindowTitle(QString::fromUtf8("Пригласительная ссылка"));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Invite link"));
    setMinimumSize(420, 560);
    setModal(true);

    auto *layout = new QVBoxLayout(this);
    layout->setSpacing(12);
-    auto* expiry = new QLabel(QStringLiteral("Ссылка действует %1 минут с момента создания.").arg(JOIN_KEY_TTL_SECONDS / 60), this);
+    auto* expiry = new QLabel(QCoreApplication::translate("ChatGui",
+        "The link expires %1 minutes after creation.").arg(JOIN_KEY_TTL_SECONDS / 60), this);
    expiry->setWordWrap(true);
    layout->addWidget(expiry);

-    auto *nodeLabel = new QLabel(QString::fromUtf8("Узел входа:"), this);
+    auto *nodeLabel = new QLabel(QCoreApplication::translate("ChatGui", "Entry node:"), this);
    nodeLabel->setStyleSheet("font-size: 12px; color: palette(window-text);");

    m_nodeCombo = new QComboBox(this);
@@ -52,10 +54,10 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW

    m_linkEdit = new QLineEdit(this);
    m_linkEdit->setReadOnly(true);
-    m_linkEdit->setPlaceholderText(QString::fromUtf8("Генерация ссылки..."));
+    m_linkEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Generating link..."));
    m_linkEdit->setStyleSheet("padding: 6px; font-family: monospace;");

-    auto *copyBtn = new QPushButton(QString::fromUtf8("Копировать"), this);
+    auto *copyBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Copy"), this);
    connect(copyBtn, &QPushButton::clicked, this, [this]() {
        QClipboard* cb = QApplication::clipboard();
        cb->setText(m_linkEdit->text(), QClipboard::Clipboard);
@@ -125,7 +127,7 @@ void ShareInviteDialog::requestLink(uint64_t targetNodeId) {
    req->request_id = m_requestId = ++nextRequestId;
    req->target_node_id = targetNodeId;
    m_linkEdit->setText(QString());
-    m_linkEdit->setPlaceholderText(QString::fromUtf8("Генерация ссылки..."));
+    m_linkEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Generating link..."));
    m_qrLabel->clear();
    gui_bridge_post_uasync_fn(chat_invite_build_link_trampoline, req);
 }
@@ -151,7 +153,7 @@ void ShareInviteDialog::onCandidates(const char* chId, int chIdLen, const uint8_

    if (autoId == 0) {
        m_linkEdit->setText(QString());
-        m_linkEdit->setPlaceholderText(QString::fromUtf8("Не удалось определить узел (см. лог)"));
+        m_linkEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Failed to identify the node (see log)"));
        return;
    }

@@ -167,7 +169,7 @@ void ShareInviteDialog::onCandidates(const char* chId, int chIdLen, const uint8_
    m_nodeCombo->clear();

    /* пункт 0 — узел, найденный авто-выбором */
-    m_nodeCombo->addItem(nodeLabel(autoId) + QString::fromUtf8(" (auto)"),
+    m_nodeCombo->addItem(nodeLabel(autoId) + QCoreApplication::translate("ChatGui", " (auto)"),
                         QVariant::fromValue((qulonglong)autoId));

    /* остальные узлы (пропуская авто), свой помечаем (self) */
@@ -179,7 +181,7 @@ void ShareInviteDialog::onCandidates(const char* chId, int chIdLen, const uint8_
        if (nid == autoId) continue;
        QString label = nodeLabel(nid);
        if (m_db && nid == m_db->myNodeId())
-            label += QString::fromUtf8(" (self)");
+            label += QCoreApplication::translate("ChatGui", " (self)");
        m_nodeCombo->addItem(label, QVariant::fromValue((qulonglong)nid));
    }

@@ -193,7 +195,7 @@ void ShareInviteDialog::onLinkReady(const char* chId, int chIdLen, uint64_t requ
    if (cid != m_channelId) return;
    if (!link || link[0] == '\0') {
        m_linkEdit->setText(QString());
-        m_linkEdit->setPlaceholderText(QString::fromUtf8("Не удалось собрать ссылку (см. лог)"));
+        m_linkEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Failed to build the link (see log)"));
        m_qrLabel->clear();
        return;
    }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "joindialog.h"
 #include "invite_link.h"
 #include "debug_ui.h"
@@ -23,7 +24,7 @@ JoinDialog::JoinDialog(UtunNode* node, DbManager* db, QWidget* parent,
    , m_node(node)
    , m_db(db)
 {
-    setWindowTitle("Join Channel");
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Join Channel"));
    setMinimumWidth(420);
    setModal(true);

@@ -31,7 +32,7 @@ JoinDialog::JoinDialog(UtunNode* node, DbManager* db, QWidget* parent,
    layout->setSpacing(12);
    layout->setContentsMargins(20, 16, 20, 16);

-    auto *titleLabel = new QLabel("Paste invite link:", this);
+    auto *titleLabel = new QLabel(QCoreApplication::translate("ChatGui", "Paste invite link:"), this);
    titleLabel->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(titleLabel);

@@ -41,8 +42,9 @@ JoinDialog::JoinDialog(UtunNode* node, DbManager* db, QWidget* parent,
        "QLineEdit { border: 1px solid palette(mid); border-radius: 6px;"
        " padding: 8px 12px; font-size: 13px; background: palette(base); }");
    layout->addWidget(m_linkEdit);
-    auto* expiry = new QLabel(QStringLiteral("Приглашение действует 10 минут с момента создания.\n"
-        "Если срок истёк, попросите отправителя создать новую ссылку."), this);
+    auto* expiry = new QLabel(QCoreApplication::translate("ChatGui",
+        "The invitation expires 10 minutes after creation.\nIf it has expired, ask the sender to "
+        "create a new link."), this);
    expiry->setWordWrap(true);
    layout->addWidget(expiry);

@@ -57,8 +59,8 @@ JoinDialog::JoinDialog(UtunNode* node, DbManager* db, QWidget* parent,
    btnLayout->setSpacing(8);
    btnLayout->addStretch();

-    m_cancelBtn = new QPushButton("Cancel", this);
-    m_cancelBtn->setFixedWidth(90);
+    m_cancelBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Cancel"), this);
+    m_cancelBtn->setMinimumWidth(90);
    m_cancelBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -66,8 +68,8 @@ JoinDialog::JoinDialog(UtunNode* node, DbManager* db, QWidget* parent,
    connect(m_cancelBtn, &QPushButton::clicked, this, &QDialog::reject);
    btnLayout->addWidget(m_cancelBtn);

-    m_connectBtn = new QPushButton("Connect", this);
-    m_connectBtn->setFixedWidth(90);
+    m_connectBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Connect"), this);
+    m_connectBtn->setMinimumWidth(90);
    m_connectBtn->setDefault(true);
    m_connectBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 4px;"
@@ -113,7 +115,7 @@ JoinDialog::JoinDialog(UtunNode* node, DbManager* db, QWidget* parent,
                              : QString("?%1").arg(a.proto);
            addrList.append(QString("%1:%2 (%3)").arg(addrStr).arg(a.port).arg(protoName));
        }
-        setStatus(QString("Node: 0x%1  |  %2")
+        setStatus(QCoreApplication::translate("ChatGui", "Node: 0x%1  %2")
            .arg(nodeId, 16, 16, QLatin1Char('0'))
            .arg(addrList.join(", ")));
    });
@@ -149,22 +151,22 @@ void JoinDialog::onConnectClicked() {
    if (m_connecting) return;
    QString link = m_linkEdit->text().trimmed();
    if (link.isEmpty()) {
-        setStatus("Enter an invite link.", true);
+        setStatus(QCoreApplication::translate("ChatGui", "Enter an invite link."), true);
        return;
    }

-    setStatus("Parsing link...");
+    setStatus(QCoreApplication::translate("ChatGui", "Parsing link..."));
    InviteData d = decodeInviteLink(link);
    if (!d.error.isEmpty()) {
-        setStatus("Invalid invite link: " + d.error, true);
+        setStatus(QCoreApplication::translate("ChatGui", "Invalid invite link: ") + d.error, true);
        return;
    }
    if (d.pubkey.size() != 32) {
-        setStatus(QString("Invalid invite link: pubkey is %1 bytes (need 32)").arg(d.pubkey.size()), true);
+        setStatus(QCoreApplication::translate("ChatGui", "Invalid invite link: pubkey is %1 bytes (need 32)").arg(d.pubkey.size()), true);
        return;
    }
    if (d.addrs.isEmpty()) {
-        setStatus("No peer addresses in the invite link.", true);
+        setStatus(QCoreApplication::translate("ChatGui", "No peer addresses in the invite link."), true);
        return;
    }

@@ -190,7 +192,7 @@ void JoinDialog::onConnectClicked() {
    m_connectBtn->setEnabled(false);
    m_linkEdit->setReadOnly(true);

-    setStatus("Connecting to peer...");
+    setStatus(QCoreApplication::translate("ChatGui", "Connecting to peer..."));

    QByteArray addrsBuf = serializeInviteAddrs(d);

@@ -206,7 +208,7 @@ void JoinDialog::onConnectResult(uint64_t nodeId, uint64_t channelId, int result
    if (!m_connecting || nodeId != m_pendingNodeId || channelId != m_pendingChannelId) return;

    if (result == 0) {
-        setStatus("Connected!");
+        setStatus(QCoreApplication::translate("ChatGui", "Connected!"));
        QString cid = QString::number(m_pendingChannelId);
        emit joined(cid);
        accept();
@@ -216,13 +218,13 @@ void JoinDialog::onConnectResult(uint64_t nodeId, uint64_t channelId, int result
        m_linkEdit->setReadOnly(false);
        m_connectBtn->setFocus();

-        const char* errMsg = "Unknown error.";
+        QString errMsg = QCoreApplication::translate("ChatGui", "Unknown error.");
        switch (result) {
-            case -1: errMsg = "Channel not found."; break;
-            case  2: errMsg = "Connection timed out."; break;
-            case -7: errMsg = "Node not initialized."; break;
+            case -1: errMsg = QCoreApplication::translate("ChatGui", "Channel not found."); break;
+            case  2: errMsg = QCoreApplication::translate("ChatGui", "Connection timed out."); break;
+            case -7: errMsg = QCoreApplication::translate("ChatGui", "Node not initialized."); break;
            default: break;
        }
-        setStatus(QString("Connection failed: %1").arg(errMsg), true);
+        setStatus(QCoreApplication::translate("ChatGui", "Connection failed: %1").arg(errMsg), true);
    }
 }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include <QApplication>
 #include <QIcon>
 #include <QPalette>
@@ -6,6 +7,8 @@
 #include <QFile>
 #include <QLockFile>
 #include <QMessageBox>
+#include <QTranslator>
+#include "gui_language.h"
 #include <cstdio>
 #ifdef _WIN32
 #include <windows.h>
@@ -75,13 +78,11 @@ int main(int argc, char *argv[]) {
    app.setDesktopFileName("org.utun.vibechat");
    app.setWindowIcon(QIcon(":/icons/app_icon.png"));
    app.setQuitOnLastWindowClosed(false);
+    debug_config_init();

-    /* single-instance: лог/БД/сокеты конфликтуют при втором запуске */
+    /* Блокировка до любых изменений конфига/БД; предупреждение после загрузки языка. */
    QLockFile lock(QCoreApplication::applicationDirPath() + "/vibechat.lock");
-    if (!lock.tryLock()) {
-        QMessageBox::warning(nullptr, "vibechat", "vibechat is already running.");
-        return 1;
-    }
+    const bool locked = lock.tryLock();

    app.setStyle(QStyleFactory::create("Fusion"));
    QPalette p;
@@ -105,10 +106,31 @@ int main(int argc, char *argv[]) {
    QString cfgDir = QCoreApplication::applicationDirPath();
    QString cfgPath = cfgDir + "/vibechat.cfg";
    /* миграция: старый конфиг chatgui.cfg → vibechat.cfg */
-    if (!QFile::exists(cfgPath) && QFile::exists(cfgDir + "/chatgui.cfg"))
+    if (locked && !QFile::exists(cfgPath) && QFile::exists(cfgDir + "/chatgui.cfg"))
        QFile::rename(cfgDir + "/chatgui.cfg", cfgPath);

    NodeConfig cfg(cfgPath);
+    if (cfg.exists() && !cfg.load()) {
+        qCritical("Cannot open/read config file: %s", qPrintable(cfgPath));
+        return 1;
+    }
+
+    QTranslator guiTranslator, qtTranslator;
+    const QString language = resolveGuiLanguage(cfg.language());
+    if (!guiTranslator.load(":/translations/chatgui_" + language + ".qm") || !app.installTranslator(&guiTranslator)) {
+        DEBUG_ERROR(DEBUG_CATEGORY_CONFIG, "GUI language: failed to load embedded catalog for %s", qPrintable(language));
+        return 1;
+    }
+    if (language == "ru") {
+        if (!qtTranslator.load(QStringLiteral(":/translations/qtbase_ru.qm")) || !app.installTranslator(&qtTranslator)) {
+            DEBUG_ERROR(DEBUG_CATEGORY_CONFIG, "GUI language: failed to load embedded Qt Russian catalog");
+            return 1;
+        }
+    }
+    if (!locked) {
+        QMessageBox::warning(nullptr, "vibechat", QCoreApplication::translate("ChatGui", "vibechat is already running."));
+        return 1;
+    }
    bool needSave = false;

    if (!cfg.exists()) {
@@ -117,10 +139,6 @@ int main(int argc, char *argv[]) {
            return 1;
        }
    } else {
-        if (!cfg.load()) {
-            qCritical("Cannot open/read config file: %s", qPrintable(cfgPath));
-            return 1;
-        }
        if (cfg.hasErrors()) {
            for (const auto& err : cfg.errors())
                fprintf(stderr, "CONFIG ERROR: %s\n", qPrintable(err));
@@ -154,12 +172,13 @@ int main(int argc, char *argv[]) {
    /* ранняя инициализация лога в GUI-потоке: SoundManager::init() вызывается в
     * конструкторе MainWindow ДО старта utun-потока, поэтому без этого его диагностика
     * (ma_engine_init и т.п.) в лог-файл не попадёт. */
-    debug_config_init();
    debug_enable_function_name(0);
    debug_enable_file_output(debugFile.toUtf8().constData(), 0);
    QString lvl = cfg.debugLevel().trimmed();
    if (lvl.isEmpty()) lvl = QStringLiteral("info");
    debug_apply_global_level(lvl.toUtf8().constData());
+    DEBUG_INFO(DEBUG_CATEGORY_CONFIG, "GUI language: preference=%s system=%s selected=%s",
+               qPrintable(cfg.language()), qPrintable(QLocale::system().uiLanguages().join(',')), qPrintable(language));

    DbManager db;
    MainWindow w(nullptr, &db, cfgPath, dbPath, debugFile,
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "mainwindow.h"
 #include "channellist.h"
 #include "messagelist.h"
@@ -437,7 +438,7 @@ void MainWindow::setupBridgeCallbacks() {
        uint64_t from; memcpy(&from, data + 1 + chLen, 8);
        s_mainWindow->m_trayIcon->showMessage(
            "vibechat",
-            QStringLiteral("You are now a channel co-owner.\nReceived admin key for channel %1 from 0x%2")
+            QCoreApplication::translate("ChatGui", "You are now a channel co-owner.\nReceived admin key for channel %1 from 0x%2")
                .arg(chId).arg(QString::number(from, 16)),
            QSystemTrayIcon::Information, 5000);
        if (s_mainWindow->m_currentChannelId == chId)
@@ -604,7 +605,7 @@ void MainWindow::onCallIncoming(const QString& chId, quint64 caller, quint64 cal

    SoundManager::instance()->playLoop("call_incoming");
    if (!isVisible() || isMinimized()) {
-        m_trayIcon->showMessage("vibechat", QStringLiteral("Incoming call from %1").arg(name),
+        m_trayIcon->showMessage("vibechat", QCoreApplication::translate("ChatGui", "Incoming call from %1").arg(name),
                                QSystemTrayIcon::Information, 5000);
    }

@@ -687,7 +688,9 @@ void MainWindow::onDmConvUpdated(const QString& convId) {
 void MainWindow::onInviteToPmRequested(const QString& source, quint64 peer, const QString& name) {
    if (!m_db || !m_db->isOpen() || !m_node || !m_node->isRunning()) {
        GUI_ERROR("invite PM: node unavailable");
-        QMessageBox::warning(this, QStringLiteral("Приглашение"), QStringLiteral("Ядро не запущено.")); return;
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+            "Invitation"), QCoreApplication::translate("ChatGui",
+            "The core is not running.")); return;
    }
    if (!peer || peer == m_db->myNodeId()) { GUI_ERROR("invite PM: invalid recipient"); return; }
    DmInviteDialog dialog(m_db, peer, name, source, this);
@@ -702,11 +705,15 @@ void MainWindow::onMessageLinkActivated(const QString& link) {
        const QUrl url(link, QUrl::StrictMode);
        if (!url.isValid() || url.host().isEmpty() || (url.scheme() != "http" && url.scheme() != "https")) {
            GUI_ERROR("message link: invalid web address bytes=%d", (int)link.size());
-            QMessageBox::warning(this, tr("Ссылка"), tr("Некорректная ссылка.")); return;
+            QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+                "Link"), QCoreApplication::translate("ChatGui",
+                "Invalid link.")); return;
        }
        if (!QDesktopServices::openUrl(url)) {
            GUI_ERROR("message link: external open failed scheme=%s host=%s", qPrintable(url.scheme()), qPrintable(url.host()));
-            QMessageBox::warning(this, tr("Ссылка"), tr("Не удалось открыть ссылку. Проверьте наличие браузера.")); return;
+            QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+                "Link"), QCoreApplication::translate("ChatGui",
+                "Failed to open the link. Check that a browser is installed.")); return;
        }
        GUI_INFO("message link: external open requested scheme=%s host=%s", qPrintable(url.scheme()), qPrintable(url.host()));
        return;
@@ -714,11 +721,15 @@ void MainWindow::onMessageLinkActivated(const QString& link) {
    const auto invite = decodeInviteLink(link);
    if (!invite.error.isEmpty()) {
        GUI_ERROR("invite link: invalid error=%s", qPrintable(invite.error));
-        QMessageBox::warning(this, QStringLiteral("Приглашение"), QStringLiteral("Некорректная ссылка: ") + invite.error); return;
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+            "Invitation"), QCoreApplication::translate("ChatGui",
+            "Invalid link: ") + invite.error); return;
    }
    if (!m_db || !m_db->isOpen() || !m_node || !m_node->isRunning()) {
        GUI_ERROR("invite link: node unavailable");
-        QMessageBox::warning(this, QStringLiteral("Приглашение"), QStringLiteral("Ядро не запущено.")); return;
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+            "Invitation"), QCoreApplication::translate("ChatGui",
+            "The core is not running.")); return;
    }
    const QString channelId = QString::number(invite.channelId);
    for (const auto& channel : m_db->getChannels()) {
@@ -751,19 +762,19 @@ void MainWindow::setupTray() {
    m_trayIcon->setToolTip("vibechat");

    m_trayMenu = new QMenu(this);
-    QAction *settingsAction = m_trayMenu->addAction("Settings");
+    QAction *settingsAction = m_trayMenu->addAction(QCoreApplication::translate("ChatGui", "Settings"));
    connect(settingsAction, &QAction::triggered, this, &MainWindow::showSettings);

    m_trayMenu->addSeparator();

-    QAction *showAction = m_trayMenu->addAction("Show");
+    QAction *showAction = m_trayMenu->addAction(QCoreApplication::translate("ChatGui", "Show"));
    connect(showAction, &QAction::triggered, this, [this]() {
        show();
        raise();
        activateWindow();
    });

-    QAction *quitAction = m_trayMenu->addAction("Quit");
+    QAction *quitAction = m_trayMenu->addAction(QCoreApplication::translate("ChatGui", "Quit"));
    connect(quitAction, &QAction::triggered, this, &MainWindow::requestShutdown);

    m_trayIcon->setContextMenu(m_trayMenu);
@@ -778,7 +789,7 @@ void MainWindow::closeEvent(QCloseEvent *event) {
    DEBUG_DEBUG(DEBUG_CATEGORY_GENERAL, "MainWindow: closeEvent — hiding to tray");
    saveWindowGeometry();
    hide();
-    m_trayIcon->showMessage("vibechat", "Application minimized to tray.",
+    m_trayIcon->showMessage("vibechat", QCoreApplication::translate("ChatGui", "Application minimized to tray."),
                             QSystemTrayIcon::Information, 2000);
    event->ignore();
 }
@@ -814,7 +825,7 @@ void MainWindow::showShareInviteDialog(const QString& channelId) {

 void MainWindow::showInviteByLinkDialog(const QString& channelId) {
    if (!m_node || !m_node->isRunning()) {
-        QMessageBox::warning(this, "Error", "Node is not running.");
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui", "Error"), QCoreApplication::translate("ChatGui", "Node is not running."));
        return;
    }
    InviteByLinkDialog dlg(channelId, m_node, this);
@@ -823,7 +834,7 @@ void MainWindow::showInviteByLinkDialog(const QString& channelId) {

 void MainWindow::showJoinDialog() {
    if (!m_node || !m_node->isRunning()) {
-        QMessageBox::warning(this, "Error", "Node is not running.");
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui", "Error"), QCoreApplication::translate("ChatGui", "Node is not running."));
        return;
    }

@@ -953,11 +964,13 @@ void MainWindow::reloadChannels() {

 void MainWindow::onCreateGroupRequested() {
    if (!m_node || !m_node->isRunning()) {
-        QMessageBox::warning(this, "Error", "Node is not running.");
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui", "Error"), QCoreApplication::translate("ChatGui", "Node is not running."));
        return;
    }
    if (!gui_bridge_is_uasync_ready()) {
-        QMessageBox::warning(this, "Error", "uTun thread is not ready yet. Please wait and try again.");
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+            "Error"), QCoreApplication::translate("ChatGui",
+            "uTun thread is not ready yet. Please wait and try again."));
        return;
    }

@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "memberlistmodel.h"
 #include "../transport/gui_bridge.h"
 #include <QPainter>
@@ -47,9 +48,11 @@ QVariant MemberListModel::data(const QModelIndex& index, int role) const {
            return sub;
        }
        if (role == Qt::ToolTipRole)
-            return QString(it->online ? "online" : "offline") + " | 0x" +
+            return (it->online ? QCoreApplication::translate("ChatGui",
+                "online") : QCoreApplication::translate("ChatGui",
+                "offline")) + " | 0x" +
                   QString("%1").arg(it->nodeId, 16, 16, QChar('0')) +
-                   ((it->flags & CHAT_MEMBER_FLAG_RADIO) ? tr(" | Radio enabled") : QString());
+                   ((it->flags & CHAT_MEMBER_FLAG_RADIO) ? QCoreApplication::translate("ChatGui", " · Radio enabled") : QString());
        if (role == Qt::UserRole + 2) return it->isSelf;
        if (role == Qt::UserRole + 3) return it->flags;
        if (role == Qt::UserRole + 4) return (bool)it->storage;
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "memberpropsdialog.h"
 #include "../db/db_manager.h"
 #include "../transport/gui_bridge.h"
@@ -25,7 +26,7 @@ MemberPropsDialog::MemberPropsDialog(DbManager* db, const QString& channelId,
    , m_flags(flags)
    , m_transferBtn(nullptr)
 {
-    setWindowTitle("Member Properties");
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Member Properties"));
    setMinimumWidth(340);
    setModal(true);

@@ -80,52 +81,52 @@ MemberPropsDialog::MemberPropsDialog(DbManager* db, const QString& channelId,
    layout->setContentsMargins(20, 16, 20, 16);

    auto* title = new QLabel(
-        QString("Node: 0x%1").arg(nodeId, 16, 16, QChar('0')) +
+        QCoreApplication::translate("ChatGui", "Node: 0x%1").arg(nodeId, 16, 16, QChar('0')) +
        (memberName.isEmpty() ? "" : QString(" (%1)").arg(memberName)),
        this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);

    m_nickEdit = new QLineEdit(this);
-    m_nickEdit->setPlaceholderText("Local nickname...");
+    m_nickEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Local nickname..."));
    m_nickEdit->setText(curNick);
    m_nickEdit->setEnabled(!isOwn);
    layout->addWidget(m_nickEdit);

-    m_adminCb = new QCheckBox("Admin", this);
+    m_adminCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Admin"), this);
    m_adminCb->setChecked(isAdmin);
    m_adminCb->setEnabled(haveKey);
    layout->addWidget(m_adminCb);

-    m_superCb = new QCheckBox("Supernode", this);
+    m_superCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Supernode"), this);
    m_superCb->setChecked(isSuper);
    m_superCb->setEnabled(haveKey);
    layout->addWidget(m_superCb);

-    m_storageCb = new QCheckBox("Storage (priority attachment keeper)", this);
+    m_storageCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Storage (priority attachment keeper)"), this);
    m_storageCb->setChecked(curStorage);
    m_storageCb->setEnabled(haveKey);
    layout->addWidget(m_storageCb);

-    m_verifiedCb = new QCheckBox("Verified", this);
+    m_verifiedCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Verified"), this);
    m_verifiedCb->setChecked(curVerified);
    m_verifiedCb->setEnabled(haveKey);
    layout->addWidget(m_verifiedCb);

-    m_deletedCb = new QCheckBox("Deleted", this);
+    m_deletedCb = new QCheckBox(QCoreApplication::translate("ChatGui", "Deleted"), this);
    m_deletedCb->setChecked(curDeleted);
    m_deletedCb->setEnabled(haveKey);
    layout->addWidget(m_deletedCb);

    if (!haveKey) {
-        auto* hint = new QLabel("(Admin/Super require channel private key)", this);
+        auto* hint = new QLabel(QCoreApplication::translate("ChatGui", "(Admin/Super require channel private key)"), this);
        hint->setStyleSheet("color: gray; font-size: 11px;");
        layout->addWidget(hint);
    }

-    m_transferBtn = new QPushButton("Transfer admin rights", this);
+    m_transferBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Transfer admin rights"), this);
    m_transferBtn->setEnabled(haveKey && !isOwn);
-    m_transferBtn->setToolTip(QStringLiteral("Send the channel private key to this member (encrypted + signed)"));
+    m_transferBtn->setToolTip(QCoreApplication::translate("ChatGui", "Send the channel private key to this member (encrypted + signed)"));
    m_transferBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -139,8 +140,8 @@ MemberPropsDialog::MemberPropsDialog(DbManager* db, const QString& channelId,
    auto* btnLayout = new QHBoxLayout();
    btnLayout->addStretch();

-    auto* cancelBtn = new QPushButton("Cancel", this);
-    cancelBtn->setFixedWidth(90);
+    auto* cancelBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Cancel"), this);
+    cancelBtn->setMinimumWidth(90);
    cancelBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -148,8 +149,8 @@ MemberPropsDialog::MemberPropsDialog(DbManager* db, const QString& channelId,
    connect(cancelBtn, &QPushButton::clicked, this, &QDialog::reject);
    btnLayout->addWidget(cancelBtn);

-    auto* saveBtn = new QPushButton("Save", this);
-    saveBtn->setFixedWidth(90);
+    auto* saveBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Save"), this);
+    saveBtn->setMinimumWidth(90);
    saveBtn->setDefault(true);
    saveBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 4px;"
@@ -214,10 +215,10 @@ void MemberPropsDialog::onTransferAdmin() {
    QString name = m_memberName.isEmpty() ? QString("0x%1").arg(m_nodeId, 16, 16, QChar('0')) : m_memberName;
    QMessageBox::StandardButton answer = QMessageBox::question(
        this,
-        QStringLiteral("Transfer admin rights"),
-        QStringLiteral("Send the channel private key to \"%1\"?\n\n"
-                       "The key is transferred encrypted and signed. The recipient will become a co-owner "
-                       "and will be able to manage members.").arg(name),
+        QCoreApplication::translate("ChatGui", "Transfer admin rights"),
+        QCoreApplication::translate("ChatGui",
+            "Send the channel private key to \"%1\"?\n\nThe key is transferred encrypted and signed. The "
+            "recipient will become a co-owner and will be able to manage members.").arg(name),
        QMessageBox::Yes | QMessageBox::No,
        QMessageBox::No);

@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "messagedelegate.h"
 #include "message_links.h"
 #include "chatview.h"
@@ -334,20 +335,20 @@ static int measureTextHeight(const QFont &font, const QString &text, int width,
 }

 static QString formatFileSize(qint64 bytes) {
-    if (bytes < 1024) return QString("%1B").arg(bytes);
+    if (bytes < 1024) return QCoreApplication::translate("ChatGui", "%1B").arg(bytes);
    double kb = bytes / 1024.0;
-    if (kb < 1024.0) return QString("%1KB").arg(kb, 0, 'f', kb < 10.0 ? 1 : 0);
+    if (kb < 1024.0) return QCoreApplication::translate("ChatGui", "%1KB").arg(kb, 0, 'f', kb < 10.0 ? 1 : 0);
    double mb = kb / 1024.0;
-    if (mb < 1024.0) return QString("%1MB").arg(mb, 0, 'f', mb < 10.0 ? 1 : 0);
+    if (mb < 1024.0) return QCoreApplication::translate("ChatGui", "%1MB").arg(mb, 0, 'f', mb < 10.0 ? 1 : 0);
    double gb = mb / 1024.0;
-    return QString("%1GB").arg(gb, 0, 'f', 1);
+    return QCoreApplication::translate("ChatGui", "%1GB").arg(gb, 0, 'f', 1);
 }

 static QString formatBitrate(qint64 bytes, qint64 durMs) {
    if (bytes <= 0 || durMs <= 0) return QString();
    qint64 kbps = bytes * 8 / durMs;
-    if (kbps >= 1000) return QString("%1Mbps").arg(kbps / 1000.0, 0, 'f', 1);
-    return QString("%1kbps").arg(kbps);
+    if (kbps >= 1000) return QCoreApplication::translate("ChatGui", "%1Mbps").arg(kbps / 1000.0, 0, 'f', 1);
+    return QCoreApplication::translate("ChatGui", "%1kbps").arg(kbps);
 }

 static int calcMaxLineWidth(const QFont &font, const QString &text, int availW) {
@@ -1308,7 +1309,9 @@ void MessageDelegate::paint(QPainter *painter, const QStyleOptionViewItem &optio
        painter->setPen(QColor(0x80, 0x80, 0x80));
        qint64 fsz = index.data(MsgFileSizeRole).toLongLong();
        QString sizeStr = formatFileSize(fsz);
-        QString stateStr = (dlState == 2) ? QString::fromUtf8("\xE2\x9C\x85") : (dlState == 1) ? "Downloading..." : "Download";
+        QString stateStr = (dlState == 2) ? QString::fromUtf8("\xE2\x9C\x85") : (dlState == 1) ? QCoreApplication::translate("ChatGui",
+            "Downloading...") : QCoreApplication::translate("ChatGui",
+            "Download");
        QString deliveryState = index.data(MsgDeliveryStateRole).toString();
        if (!deliveryState.isEmpty()) stateStr = deliveryState;
        QString info = sizeStr + " \xC2\xB7 " + stateStr;
@@ -1582,7 +1585,7 @@ void MessageDelegate::drawStatusBar(QPainter *p, const Layout &L,

    QString statusText;
    if (index.data(MsgEditedRole).toBool()) {
-        statusText = QString::fromUtf8("изменено  ");
+        statusText = QCoreApplication::translate("ChatGui", "edited  ");
    }
    statusText += index.data(MsgTimeRole).toString();
    p->drawText(QRect(r.left(), r.top(), r.width(), r.height()),
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "messagelist.h"
 #include "debug_ui.h"
 #include "chatview.h"
@@ -353,7 +354,7 @@ MessageList::MessageList(DbManager* db, AudioRecorder* recorder, QWidget *parent
        hl->addWidget(m_peerStatus);
        m_channelTitle = new QLabel(header);
        m_channelTitle->setStyleSheet("font-weight: bold; font-size: 14px;");
-        m_channelTitle->setText(QStringLiteral("Канал"));
+        m_channelTitle->setText(QCoreApplication::translate("ChatGui", "Channel"));
        hl->addWidget(m_channelTitle, 1);

        m_talkingLabel = new QLabel(header);
@@ -362,8 +363,8 @@ MessageList::MessageList(DbManager* db, AudioRecorder* recorder, QWidget *parent
        hl->addWidget(m_talkingLabel);

        m_inviteBtn = new QPushButton(QStringLiteral("+"), header);
-        m_inviteBtn->setAccessibleName(QStringLiteral("Пригласить в группу"));
-        m_inviteBtn->setToolTip(QStringLiteral("Пригласить в группу"));
+        m_inviteBtn->setAccessibleName(QCoreApplication::translate("ChatGui", "Invite to group"));
+        m_inviteBtn->setToolTip(QCoreApplication::translate("ChatGui", "Invite to group"));
        m_inviteBtn->setFixedSize(34, 30);
        m_inviteBtn->setCursor(Qt::PointingHandCursor);
        m_inviteBtn->hide();
@@ -380,7 +381,7 @@ MessageList::MessageList(DbManager* db, AudioRecorder* recorder, QWidget *parent
        });

        m_callBtn = new QPushButton(QStringLiteral("☎"), header);
-        m_callBtn->setAccessibleName(QStringLiteral("Позвонить"));
+        m_callBtn->setAccessibleName(QCoreApplication::translate("ChatGui", "Call peer"));
        m_callBtn->setFixedSize(34, 30);
        m_callBtn->setCursor(Qt::PointingHandCursor);
        m_callBtn->hide();
@@ -394,11 +395,11 @@ MessageList::MessageList(DbManager* db, AudioRecorder* recorder, QWidget *parent
        m_radioBtn = new QPushButton(header);
        m_radioBtn->setIcon(makeRadioIcon(header->palette().color(QPalette::ButtonText)));
        m_radioBtn->setIconSize(QSize(24, 24));
-        m_radioBtn->setAccessibleName(QStringLiteral("Рация"));
+        m_radioBtn->setAccessibleName(QCoreApplication::translate("ChatGui", "Radio"));
        m_radioBtn->setCheckable(true);
        m_radioBtn->setFixedSize(34, 30);
        m_radioBtn->setCursor(Qt::PointingHandCursor);
-        m_radioBtn->setToolTip(QStringLiteral("Рация: включить/выключить прослушивание канала"));
+        m_radioBtn->setToolTip(QCoreApplication::translate("ChatGui", "Radio: toggle channel listening"));
        m_radioBtn->setStyleSheet(
            "QPushButton { border: 1px solid palette(mid); border-radius: 6px; background: palette(base); font-size: 15px; }"
            "QPushButton:checked { background: #27ae60; border-color: #27ae60; }");
@@ -1023,17 +1024,17 @@ void MessageList::onMessageContextMenu(const QPoint& pos) {
    bool downloaded = !filePath.isEmpty() && QFile::exists(filePath);

    QMenu menu(m_view);
-    QAction* saveAct = menu.addAction(QString::fromUtf8("Сохранить в файл"));
+    QAction* saveAct = menu.addAction(QCoreApplication::translate("ChatGui", "Save to file"));
    saveAct->setEnabled(downloaded);
    QAction* dlAct = nullptr;
-    if (!downloaded && !isDm) dlAct = menu.addAction(QString::fromUtf8("Скачать"));
+    if (!downloaded && !isDm) dlAct = menu.addAction(QCoreApplication::translate("ChatGui", "Download"));

    QAction* chosen = menu.exec(m_view->viewport()->mapToGlobal(pos));

    if (chosen == saveAct) {
        QString base = displayName;
        if (base.isEmpty()) base = QFileInfo(filePath).fileName();
-        QString dest = QFileDialog::getSaveFileName(this, QString::fromUtf8("Сохранить файл"), base);
+        QString dest = QFileDialog::getSaveFileName(this, QCoreApplication::translate("ChatGui", "Save file"), base);
        if (dest.isEmpty()) return;
        std::thread([filePath, dest]() {
            if (!QFile::copy(filePath, dest))
@@ -1063,9 +1064,9 @@ void MessageList::onMessageContextMenu(const QPoint& pos) {
 void MessageList::clearDmCallRoute() {
    m_callPeer = 0; m_callGroup = 0;
    m_callBtn->setEnabled(false);
-    m_callBtn->setToolTip(QStringLiteral("Собеседник недоступен"));
+    m_callBtn->setToolTip(QCoreApplication::translate("ChatGui", "Peer unavailable"));
    m_peerStatus->setStyleSheet("background: #E53935; border-radius: 6px;");
-    m_peerStatus->setToolTip(QStringLiteral("Не в сети"));
+    m_peerStatus->setToolTip(QCoreApplication::translate("ChatGui", "Offline"));
 }

 void MessageList::refreshDmCallRoute() {
@@ -1095,8 +1096,8 @@ void MessageList::onDmCallRoute(const uint8_t* data, int len) {
    m_callPeer = peer; m_callGroup = group;
    m_callBtn->setEnabled(peer && group);
    m_peerStatus->setStyleSheet(group ? "background: #4CAF50; border-radius: 6px;" : "background: #E53935; border-radius: 6px;");
-    m_peerStatus->setToolTip(group ? QStringLiteral("В сети") : QStringLiteral("Не в сети"));
-    m_callBtn->setToolTip(group ? QStringLiteral("Позвонить") : QStringLiteral("Собеседник недоступен"));
+    m_peerStatus->setToolTip(group ? QCoreApplication::translate("ChatGui", "Online") : QCoreApplication::translate("ChatGui", "Offline"));
+    m_callBtn->setToolTip(group ? QCoreApplication::translate("ChatGui", "Call peer") : QCoreApplication::translate("ChatGui", "Peer unavailable"));
 }

 bool MessageList::isDmChannel(const QString& channelId) {
@@ -1155,7 +1156,7 @@ void MessageList::onDmMessages(const uint8_t* data, int len) {
        const QString inviteLink = invite ? text : QString();
        if (invite) {
            const QString groupName = message.value("tags").toObject().value("group_name").toString();
-            text = tr("Приглашение в группу «%1»").arg(groupName) + '\n' + inviteLink;
+            text = QCoreApplication::translate("ChatGui", "Invitation to group “%1”").arg(groupName) + '\n' + inviteLink;
            GUI_DEBUG("invite PM: rendered conv=%s seq=%lld group_name_bytes=%d link_bytes=%d", qPrintable(m_currentChannelId),
                      (long long)seq, (int)groupName.toUtf8().size(), (int)inviteLink.size());
        }
@@ -1163,12 +1164,14 @@ void MessageList::onDmMessages(const uint8_t* data, int len) {
        QString state = message.value("media_status").toString();
        QString status;
        if (file) {
-            if (state == "delivered") status = QString::fromUtf8("Доставлено");
-            else if (state == "expired") status = QString::fromUtf8("Срок хранения истёк");
-            else if (dir == 1) status = QString::fromUtf8("Ожидает доставки");
-            else if (state == "ready") status = QString::fromUtf8("Получено");
-            else status = QString::fromUtf8("Загрузка…");
-        } else if (dir == 1) status = message.value("pending").toBool() ? QString::fromUtf8("Ожидает доставки") : QString::fromUtf8("Доставлено");
+            if (state == "delivered") status = QCoreApplication::translate("ChatGui", "Delivered");
+            else if (state == "expired") status = QCoreApplication::translate("ChatGui", "Storage period expired");
+            else if (dir == 1) status = QCoreApplication::translate("ChatGui", "Awaiting delivery");
+            else if (state == "ready") status = QCoreApplication::translate("ChatGui", "Received");
+            else status = QCoreApplication::translate("ChatGui", "Downloading…");
+        } else if (dir == 1) status = message.value("pending").toBool() ? QCoreApplication::translate("ChatGui",
+            "Awaiting delivery") : QCoreApplication::translate("ChatGui",
+            "Delivered");

        AccountRow acc = m_db ? m_db->getAccount(author) : AccountRow();
        QString name = authorName(author);
@@ -1228,7 +1231,7 @@ void MessageList::onRadioTalk(quint64 groupId, quint64 srcNodeId, bool on) {
    if (on) {
        QString name = authorName(srcNodeId);
        if (name.isEmpty()) name = QStringLiteral("0x%1").arg(srcNodeId, 0, 16);
-        m_talkingLabel->setText(QString::fromUtf8("\xF0\x9F\x8E\x99 %1 говорит").arg(name));
+        m_talkingLabel->setText(QCoreApplication::translate("ChatGui", "🎙 %1 is speaking").arg(name));
        m_talkingLabel->show();
    } else {
        m_talkingLabel->hide();
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 // networksettingspage.cpp — Network configuration form (список listen-сокетов)
 #include "networksettingspage.h"
 #include "../transport/config_updater.h"
@@ -13,7 +14,7 @@
 #include <QFile>
 #include <QTextStream>

-static const QString AUTO_IP_LABEL = "Auto (0.0.0.0)";
+static QString autoIpLabel() { return QCoreApplication::translate("ChatGui", "Auto (0.0.0.0)"); }

 NetworkSettingsPage::NetworkSettingsPage(QWidget* parent)
    : QWidget(parent)
@@ -22,11 +23,11 @@ NetworkSettingsPage::NetworkSettingsPage(QWidget* parent)
    layout->setSpacing(12);
    layout->setContentsMargins(0, 0, 0, 0);

-    auto* title = new QLabel("Listen Sockets", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "Listen Sockets"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);

-    m_autoSocketsCheck = new QCheckBox("Auto sockets (UDP+TCP from interfaces)", this);
+    m_autoSocketsCheck = new QCheckBox(QCoreApplication::translate("ChatGui", "Auto sockets (UDP+TCP from interfaces)"), this);
    layout->addWidget(m_autoSocketsCheck);

    m_serverList = new QListWidget(this);
@@ -34,8 +35,8 @@ NetworkSettingsPage::NetworkSettingsPage(QWidget* parent)
    layout->addWidget(m_serverList);

    auto* btnRow = new QHBoxLayout();
-    m_addBtn = new QPushButton("Add", this);
-    m_removeBtn = new QPushButton("Remove", this);
+    m_addBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Add"), this);
+    m_removeBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Remove"), this);
    btnRow->addWidget(m_addBtn);
    btnRow->addWidget(m_removeBtn);
    btnRow->addStretch();
@@ -44,41 +45,44 @@ NetworkSettingsPage::NetworkSettingsPage(QWidget* parent)
    // --- форма правки выбранного сокета ---
    auto* formLayout = new QGridLayout();

-    formLayout->addWidget(new QLabel("Name:", this), 0, 0);
+    formLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Name:"), this), 0, 0);
    m_nameEdit = new QLineEdit(this);
    m_nameEdit->setMinimumWidth(180);
    formLayout->addWidget(m_nameEdit, 0, 1);

-    formLayout->addWidget(new QLabel("IP Address:", this), 1, 0);
+    formLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "IP Address:"), this), 1, 0);
    m_ipCombo = new QComboBox(this);
    m_ipCombo->setEditable(true);
    m_ipCombo->setMinimumWidth(180);
    formLayout->addWidget(m_ipCombo, 1, 1);

-    formLayout->addWidget(new QLabel("Port:", this), 2, 0);
+    formLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Port:"), this), 2, 0);
    m_portSpin = new QSpinBox(this);
    m_portSpin->setRange(1, 65535);
    m_portSpin->setValue(1333);
    formLayout->addWidget(m_portSpin, 2, 1);

-    formLayout->addWidget(new QLabel("Protocol:", this), 3, 0);
+    formLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Protocol:"), this), 3, 0);
    m_protoCombo = new QComboBox(this);
    m_protoCombo->addItems({"UDP", "TCP"});
    formLayout->addWidget(m_protoCombo, 3, 1);

-    formLayout->addWidget(new QLabel("Type:", this), 4, 0);
+    formLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Type:"), this), 4, 0);
    m_typeCombo = new QComboBox(this);
-    m_typeCombo->addItems({"public", "nat", "private", "local"});
+    m_typeCombo->addItem(QCoreApplication::translate("ChatGui", "Public"), QStringLiteral("public"));
+    m_typeCombo->addItem(QStringLiteral("NAT"), QStringLiteral("nat"));
+    m_typeCombo->addItem(QCoreApplication::translate("ChatGui", "Private"), QStringLiteral("private"));
+    m_typeCombo->addItem(QCoreApplication::translate("ChatGui", "Local"), QStringLiteral("local"));
    formLayout->addWidget(m_typeCombo, 4, 1);

-    formLayout->addWidget(new QLabel("Interface:", this), 5, 0);
+    formLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Interface:"), this), 5, 0);
    m_interfaceCombo = new QComboBox(this);
    m_interfaceCombo->setMinimumWidth(180);
    formLayout->addWidget(m_interfaceCombo, 5, 1);

    layout->addLayout(formLayout);

-    auto* note = new QLabel("Changes take effect after restart.", this);
+    auto* note = new QLabel(QCoreApplication::translate("ChatGui", "Changes take effect after restart."), this);
    note->setStyleSheet("color: gray; font-size: 11px;");
    layout->addWidget(note);
    layout->addStretch();
@@ -111,7 +115,7 @@ static void splitAddr(const QString& addr, QString& ip, int& port) {
 }

 void NetworkSettingsPage::populateInterfaces() {
-    m_interfaceCombo->addItem("Auto (any)");
+    m_interfaceCombo->addItem(QCoreApplication::translate("ChatGui", "Auto (any)"));
    for (const QNetworkInterface& iface : QNetworkInterface::allInterfaces()) {
        if (iface.flags() & QNetworkInterface::IsLoopBack) continue;
        if (!(iface.flags() & QNetworkInterface::IsUp)) continue;
@@ -120,7 +124,7 @@ void NetworkSettingsPage::populateInterfaces() {
 }

 void NetworkSettingsPage::populateAddresses() {
-    m_ipCombo->addItem(AUTO_IP_LABEL);
+    m_ipCombo->addItem(autoIpLabel());
    for (const QNetworkInterface& iface : QNetworkInterface::allInterfaces()) {
        if (iface.flags() & QNetworkInterface::IsLoopBack) continue;
        if (!(iface.flags() & QNetworkInterface::IsUp)) continue;
@@ -166,11 +170,11 @@ void NetworkSettingsPage::loadFormFromSelected() {
    m_nameEdit->setText(s.name);
    QString ip; int port = 0;
    splitAddr(s.addr, ip, port);
-    if (ip == "0.0.0.0") ip = AUTO_IP_LABEL;
+    if (ip == "0.0.0.0") ip = autoIpLabel();
    m_ipCombo->setCurrentText(ip);
    m_portSpin->setValue(port > 0 ? port : 1333);
    m_protoCombo->setCurrentIndex(s.transport == "tcp" ? 1 : 0);
-    int typeIdx = m_typeCombo->findText(s.type);
+    int typeIdx = m_typeCombo->findData(s.type);
    m_typeCombo->setCurrentIndex(typeIdx >= 0 ? typeIdx : 0);
    int ifIdx = m_interfaceCombo->findText(s.netif);
    m_interfaceCombo->setCurrentIndex(ifIdx >= 0 ? ifIdx : 0);
@@ -185,13 +189,13 @@ void NetworkSettingsPage::updateSelectedServerFromForm() {
    s.name = m_nameEdit->text().trimmed();

    QString ip = m_ipCombo->currentText().trimmed();
-    if (ip == AUTO_IP_LABEL) ip = "0.0.0.0";
+    if (ip == autoIpLabel()) ip = "0.0.0.0";
    s.addr = ip + ":" + QString::number(m_portSpin->value());

    s.transport = (m_protoCombo->currentIndex() == 1) ? "tcp" : "udp";
-    s.type = m_typeCombo->currentText().trimmed();
+    s.type = m_typeCombo->currentData().toString();
    QString iface = m_interfaceCombo->currentText();
-    s.netif = iface.startsWith("Auto") ? QString() : iface;
+    s.netif = m_interfaceCombo->currentIndex() == 0 ? QString() : iface;
 }

 void NetworkSettingsPage::updateSelectedListItemText() {
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 // nodespage.cpp — Nodes table + dump in settings
 #include "nodespage.h"
 #include "../db/db_manager.h"
@@ -59,12 +60,15 @@ NodesPage::NodesPage(DbManager* db, QWidget* parent)
    layout->setSpacing(8);
    layout->setContentsMargins(0, 0, 0, 0);

-    auto* title = new QLabel("Known Nodes", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "Known Nodes"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);

    m_table = new QTableWidget(0, 5, this);
-    m_table->setHorizontalHeaderLabels({"Node ID", "Name", "x25519", "ed25519", "Addrs"});
+    m_table->setHorizontalHeaderLabels({QCoreApplication::translate("ChatGui",
+        "Node ID"), QCoreApplication::translate("ChatGui",
+        "Name"), "x25519", "ed25519", QCoreApplication::translate("ChatGui",
+        "Addrs")});
    m_table->horizontalHeader()->setStretchLastSection(true);
    m_table->setSelectionBehavior(QAbstractItemView::SelectRows);
    m_table->setSelectionMode(QAbstractItemView::SingleSelection);
@@ -78,7 +82,7 @@ NodesPage::NodesPage(DbManager* db, QWidget* parent)
        " font-weight: bold; font-size: 9px; }");
    layout->addWidget(m_table, 2);

-    auto* dumpLabel = new QLabel("Details", this);
+    auto* dumpLabel = new QLabel(QCoreApplication::translate("ChatGui", "Details"), this);
    dumpLabel->setStyleSheet("font-weight: bold; font-size: 12px; margin-top: 8px;");
    layout->addWidget(dumpLabel);

@@ -88,13 +92,13 @@ NodesPage::NodesPage(DbManager* db, QWidget* parent)
    m_dumpText->setStyleSheet(
        "QPlainTextEdit { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 8px; background: palette(base); }");
-    m_dumpText->setPlaceholderText("Click Refresh to load nodes");
+    m_dumpText->setPlaceholderText(QCoreApplication::translate("ChatGui", "Click Refresh to load nodes"));
    layout->addWidget(m_dumpText, 3);

    auto* btnLayout = new QHBoxLayout();
    btnLayout->addStretch();
-    m_refreshBtn = new QPushButton("Refresh", this);
-    m_refreshBtn->setFixedWidth(90);
+    m_refreshBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Refresh"), this);
+    m_refreshBtn->setMinimumWidth(90);
    m_refreshBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -109,7 +113,7 @@ void NodesPage::onRefreshClicked() { refreshNodes(); }
 void NodesPage::refreshNodes() {
    if (!m_db || !m_db->m_db) {
        m_table->setRowCount(0);
-        m_dumpText->setPlainText(QString("Database not connected (m_db=%1, m_db->m_db=%2)")
+        m_dumpText->setPlainText(QCoreApplication::translate("ChatGui", "Database not connected (m_db=%1, m_db->m_db=%2)")
            .arg((quintptr)m_db, 0, 16).arg(m_db ? (quintptr)m_db->m_db : 0, 0, 16));
        qWarning("NodesPage::refreshNodes: DB not ready m_db=%p m_db->m_db=%p", (void*)m_db, m_db ? (void*)m_db->m_db : nullptr);
        return;
@@ -167,7 +171,7 @@ void NodesPage::refreshNodes() {
        "SELECT node_id, name, x25519_pubkey, ed25519_pubkey,"
        " last_seen_at, created_at FROM nodes ORDER BY node_id",
        -1, &st, nullptr);
-    if (!st) { m_dumpText->setPlainText("Query error"); return; }
+    if (!st) { m_dumpText->setPlainText(QCoreApplication::translate("ChatGui", "Query error")); return; }

    int nodeCount = 0;
    while (sqlite3_step(st) == SQLITE_ROW) {
@@ -181,15 +185,17 @@ void NodesPage::refreshNodes() {
        qint64 last_seen = sqlite3_column_int64(st, 4);
        qint64 created = sqlite3_column_int64(st, 5);

-        dump += QString("Node: %1").arg(hex16(nid));
+        dump += QCoreApplication::translate("ChatGui", "Node: %1").arg(hex16(nid));
        if (!name.isEmpty()) dump += QString(" (%1)").arg(name);
        dump += QString("  id=0x%1\n").arg(nid, 16, 16, QChar('0'));
        dump += QString("  x25519: %1\n").arg(x25.isEmpty() ? "-" : shortenKey(x25));
        dump += QString("  ed25519: %1\n").arg(ed.isEmpty()  ? "-" : shortenKey(ed));
        if (last_seen > 0)
-            dump += QString("  last_seen: %1\n").arg(QDateTime::fromSecsSinceEpoch(last_seen).toString("yyyy-MM-dd hh:mm:ss"));
+            dump += QCoreApplication::translate("ChatGui",
+                "  last seen: %1\n").arg(QDateTime::fromSecsSinceEpoch(last_seen).toString("yyyy-MM-dd hh:mm:ss"));
        if (created > 0)
-            dump += QString("  created: %1\n").arg(QDateTime::fromSecsSinceEpoch(created).toString("yyyy-MM-dd hh:mm:ss"));
+            dump += QCoreApplication::translate("ChatGui",
+                "  created: %1\n").arg(QDateTime::fromSecsSinceEpoch(created).toString("yyyy-MM-dd hh:mm:ss"));

        sqlite3_stmt* na = nullptr;
        sqlite3_prepare_v2(d,
@@ -200,7 +206,7 @@ void NodesPage::refreshNodes() {
            sqlite3_bind_int64(na, 1, (sqlite3_int64)nid);
            int ac = 0;
            while (sqlite3_step(na) == SQLITE_ROW) {
-                if (ac == 0) dump += "  addresses:\n";
+                if (ac == 0) dump += QCoreApplication::translate("ChatGui", "  addresses:\n");
                int family = sqlite3_column_int(na, 0);
                int proto  = sqlite3_column_int(na, 1);
                const void* addr = sqlite3_column_blob(na, 2);
@@ -219,14 +225,14 @@ void NodesPage::refreshNodes() {
                }
                ac++;
            }
-            if (ac == 0) dump += "  addresses: none\n";
+            if (ac == 0) dump += QCoreApplication::translate("ChatGui", "  addresses: none\n");
            sqlite3_finalize(na);
        } else {
-            dump += "  addresses: none\n";
+            dump += QCoreApplication::translate("ChatGui", "  addresses: none\n");
        }
    }
    sqlite3_finalize(st);

-    if (nodeCount == 0) dump = "No nodes found.";
+    if (nodeCount == 0) dump = QCoreApplication::translate("ChatGui", "No nodes found.");
    m_dumpText->setPlainText(dump);
 }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "ptt_hotkey_manager.h"
 #include "radio_audio_engine.h"
 #include "../db/db_manager.h"
@@ -196,7 +197,7 @@ QString PttHotkeyManager::keyName(int key) const {
        if (name) return QString::fromLatin1(name);
    }
 #endif
-    return QString("Key %1").arg(key);
+    return QCoreApplication::translate("ChatGui", "Key %1").arg(key);
 }

 QString PttHotkeyManager::describe(const PttKeyChord& chord) const {
@@ -204,7 +205,7 @@ QString PttHotkeyManager::describe(const PttKeyChord& chord) const {
    std::sort(keys.begin(), keys.end());
    QStringList names;
    for (int key : keys) names << keyName(key);
-    return names.isEmpty() ? QStringLiteral("Не задано") : names.join(" + ");
+    return names.isEmpty() ? QCoreApplication::translate("ChatGui", "Not set") : names.join(" + ");
 }

 bool PttHotkeyManager::usesPortal() {
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "ptt_portal.h"
 #include "../../lib/debug_config.h"

@@ -50,7 +51,7 @@ void PttPortal::setStatus(const QString& text) { m_status = text; emit statusCha
 void PttPortal::initialize() {
    if (busy() || m_state == State::Ready || m_state == State::Unbound) return;
    m_state = State::Checking;
-    setStatus("Подключение глобальных хоткеев…");
+    setStatus(QCoreApplication::translate("ChatGui", "Connecting global shortcuts…"));
    auto message = QDBusMessage::createMethodCall(kService, kPath, "org.freedesktop.DBus.Properties", "Get");
    message.setArguments({kInterface, "version"});
    auto* watcher = new QDBusPendingCallWatcher(QDBusConnection::sessionBus().asyncCall(message), this);
@@ -108,7 +109,7 @@ void PttPortal::response(uint code, const QVariantMap& results, const QDBusMessa
    DEBUG_DEBUG(DEBUG_CATEGORY_RADIO, "PTT portal: response state=%d code=%u", int(state), code);
    if (code != 0) {
        fail(QString("request %1: response=%2%3").arg(int(state)).arg(code).arg(code == 1 ? " (cancelled)" : ""));
-        if (code == 1) setStatus("Назначение отменено. Нажмите кнопку, чтобы повторить.");
+        if (code == 1) setStatus(QCoreApplication::translate("ChatGui", "Assignment cancelled. Click the button to try again."));
        return;
    }
    if (state == State::Creating) {
@@ -127,11 +128,11 @@ void PttPortal::response(uint code, const QVariantMap& results, const QDBusMessa
        m_configureAfterBind = known.size() == 3 && m_configureRequested;
        m_state = State::Unbound;
        if (!known.isEmpty() || m_configureRequested) bind();
-        else setStatus("Назначьте сочетание в системных настройках.");
+        else setStatus(QCoreApplication::translate("ChatGui", "Assign a shortcut in system settings."));
    } else if (state == State::Binding) {
        m_state = State::Ready;
        updateDescriptions(qdbus_cast<PttPortalShortcuts>(results.value("shortcuts")));
-        setStatus("Глобальные хоткеи подключены.");
+        setStatus(QCoreApplication::translate("ChatGui", "Global shortcuts connected."));
        DEBUG_INFO(DEBUG_CATEGORY_RADIO, "PTT portal: bindings ready session=%s", qPrintable(m_session));
        // Первое BindShortcuts само открывает окно назначения, повторное Configure — отдельный вызов.
        m_configureRequested = false;
@@ -143,9 +144,10 @@ bool PttPortal::isPttId(const QString& id) { return id == "ptt1" || id == "ptt2"

 void PttPortal::bind() {
    PttPortalShortcuts shortcuts;
-    for (int i = 1; i <= 3; i++) shortcuts << PttPortalShortcut{QString("ptt%1").arg(i), {{"description", QString("Рация: передача %1").arg(i)}}};
+    for (int i = 1; i <= 3; i++) shortcuts << PttPortalShortcut{QString("ptt%1").arg(i), {{"description", QCoreApplication::translate("ChatGui",
+        "Radio: transmit %1").arg(i)}}};
    m_state = State::Binding;
-    setStatus("Назначение глобальных хоткеев…");
+    setStatus(QCoreApplication::translate("ChatGui", "Assigning global shortcuts…"));
    request("BindShortcuts", {QVariant::fromValue(QDBusObjectPath(m_session)), QVariant::fromValue(shortcuts), m_parentWindow}, {});
 }

@@ -230,6 +232,6 @@ void PttPortal::fail(const QString& detail) {
    m_configureRequested = m_configureAfterBind = false;
    m_state = State::Failed;
    m_descriptions = {"", "", ""}; emit descriptionsChanged();
-    setStatus("Глобальные хоткеи недоступны. Повторите назначение; подробности в логе radio.");
+    setStatus(QCoreApplication::translate("ChatGui", "Global shortcuts unavailable. Try assigning again; see the radio log for details."));
 }
 void PttPortal::sessionClosed() { fail("portal session closed"); }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "radio_audio_engine.h"
 #include "sound_manager.h"
 #include "../transport/audio_diagnostics.h"
@@ -82,7 +83,7 @@ void RadioAudioEngine::loadSettings(const QString& configPath) {
 /* Проверяем значения и атомарно сохраняем INI до отправки команды в ядро. */
 bool RadioAudioEngine::applySettings(const QMap<QString, int>& values) {
    if (!m_settingsReady || m_settingsBusy || !gui_bridge_is_uasync_ready() || !gui_bridge_get_inst()) {
-        m_settingsError = QStringLiteral("Настройки рации ещё не готовы");
+        m_settingsError = QCoreApplication::translate("ChatGui", "Radio settings are not ready yet");
        DEBUG_WARN(DEBUG_CATEGORY_RADIO, "RadioAudio: cannot apply settings ready=%d busy=%d", m_settingsReady, m_settingsBusy);
        emit stateChanged();
        return false;
@@ -92,7 +93,7 @@ bool RadioAudioEngine::applySettings(const QMap<QString, int>& values) {
        size_t index = 0;
        while (index < next.size() && it.key() != QLatin1String(settingKeys[index])) ++index;
        if (index == next.size() || it.value() < settingMin[index] || it.value() > settingMax[index]) {
-            m_settingsError = QStringLiteral("Некорректная настройка рации: %1").arg(it.key());
+            m_settingsError = QCoreApplication::translate("ChatGui", "Invalid radio setting: %1").arg(it.key());
            DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioAudio: invalid setting %s=%d", qPrintable(it.key()), it.value());
            emit stateChanged();
            return false;
@@ -103,7 +104,7 @@ bool RadioAudioEngine::applySettings(const QMap<QString, int>& values) {
    if (next != m_settings && !m_configPath.isEmpty()) {
        QFile input(m_configPath);
        if (!input.open(QIODevice::ReadOnly)) {
-            m_settingsError = QStringLiteral("Не удалось прочитать конфигурацию: %1").arg(input.errorString());
+            m_settingsError = QCoreApplication::translate("ChatGui", "Failed to read configuration: %1").arg(input.errorString());
            DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioAudio: read config failed: %s", qPrintable(input.errorString()));
            emit stateChanged();
            return false;
@@ -116,7 +117,7 @@ bool RadioAudioEngine::applySettings(const QMap<QString, int>& values) {
        if (!data.endsWith('\n')) data.append('\n');
        QSaveFile output(m_configPath);
        if (!output.open(QIODevice::WriteOnly) || output.write(data) != data.size() || !output.commit()) {
-            m_settingsError = QStringLiteral("Не удалось сохранить конфигурацию: %1").arg(output.errorString());
+            m_settingsError = QCoreApplication::translate("ChatGui", "Failed to save configuration: %1").arg(output.errorString());
            DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioAudio: save config failed: %s", qPrintable(output.errorString()));
            emit stateChanged();
            return false;
@@ -131,7 +132,7 @@ void RadioAudioEngine::postSettings(const std::array<int, 6>& values, bool apply
    auto* inst = gui_bridge_get_inst();
    void* memory = inst && gui_bridge_is_uasync_ready() ? u_malloc(sizeof(SettingsRequest)) : nullptr;
    if (!memory) {
-        m_settingsError = QStringLiteral("Не удалось отправить настройки рации в ядро");
+        m_settingsError = QCoreApplication::translate("ChatGui", "Failed to send radio settings to the core");
        DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioAudio: settings request unavailable inst=%d uasync=%d",
                    inst != nullptr, gui_bridge_is_uasync_ready());
        emit stateChanged();
@@ -164,7 +165,7 @@ void RadioAudioEngine::postSettings(const std::array<int, 6>& values, bool apply
            engine->m_settings = snapshot;
            engine->m_settingsReady = true;
            engine->m_settingsBusy = false;
-            if (!success) engine->m_settingsError = QStringLiteral("Ядро отклонило настройки рации");
+            if (!success) engine->m_settingsError = QCoreApplication::translate("ChatGui", "The core rejected radio settings");
            DEBUG_INFO(DEBUG_CATEGORY_RADIO, "RadioAudio: settings applied=%d vad=%d threshold=%d hangover=%dms TX_AGC=%d "
                       "TX_gain=%ddB VAD_gain=%ddB", success, snapshot[0], snapshot[1], snapshot[2], snapshot[3], snapshot[4], snapshot[5]);
            if ((changed || apply) && engine->m_active) engine->reconfigureCapture();
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "radiopanel.h"
 #include "radio_audio_engine.h"
 #include "sound_manager.h"
@@ -24,8 +25,8 @@ RadioPanel::RadioPanel(QWidget* parent) : QWidget(parent) {
    row->setSpacing(8);
    m_input = new QToolButton(this);
    m_output = new QToolButton(this);
-    m_input->setText(QStringLiteral("Микрофон"));
-    m_output->setText(QStringLiteral("Выход звука"));
+    m_input->setText(QCoreApplication::translate("ChatGui", "Microphone"));
+    m_output->setText(QCoreApplication::translate("ChatGui", "Audio output"));
    m_input->setObjectName(QStringLiteral("radioInputButton"));
    m_output->setObjectName(QStringLiteral("radioOutputButton"));
    for (auto* button : {m_input, m_output}) {
@@ -43,15 +44,15 @@ RadioPanel::RadioPanel(QWidget* parent) : QWidget(parent) {
    row->addWidget(m_status, 1);
    m_vad = new QPushButton(QStringLiteral("VAD"), this);
    m_vad->setObjectName(QStringLiteral("radioVadButton"));
-    m_vad->setAccessibleName(QStringLiteral("Автоматическая передача по голосу"));
+    m_vad->setAccessibleName(QCoreApplication::translate("ChatGui", "Automatic voice transmission"));
    m_vad->setCheckable(true);
    m_vad->setFixedSize(52, 34);
    m_vad->setStyleSheet("QPushButton:checked { background: #3390EC; color: white; }");
    row->addWidget(m_vad);
    m_ptt = new QPushButton(QStringLiteral("PTT"), this);
    m_ptt->setObjectName(QStringLiteral("radioPttButton"));
-    m_ptt->setAccessibleName(QStringLiteral("Держите и говорите"));
-    m_ptt->setToolTip(QStringLiteral("Держите кнопку или глобальный хоткей для передачи"));
+    m_ptt->setAccessibleName(QCoreApplication::translate("ChatGui", "Hold to talk"));
+    m_ptt->setToolTip(QCoreApplication::translate("ChatGui", "Hold the button or a global shortcut to transmit"));
    m_ptt->setFixedSize(64, 34);
    m_ptt->setStyleSheet("QPushButton[transmitting=\"true\"] { background: #27ae60; color: white; }");
    row->addWidget(m_ptt);
@@ -82,16 +83,16 @@ void RadioPanel::updateState() {
        m_ptt->update();
    }
    QString state;
-    if (!engine->settingsError().isEmpty()) state = QStringLiteral("Ошибка настройки");
-    else if (engine->settingsBusy()) state = QStringLiteral("Применение настроек…");
-    else if (!engine->captureAvailable()) state = QStringLiteral("Микрофон недоступен");
-    else if (engine->vadEnabled() && !engine->vadAvailable()) state = QStringLiteral("VAD недоступен");
-    else if (transmitting) state = QStringLiteral("Передача");
-    else state = engine->vadEnabled() ? QStringLiteral("VAD слушает") : QStringLiteral("Приём");
+    if (!engine->settingsError().isEmpty()) state = QCoreApplication::translate("ChatGui", "Settings error");
+    else if (engine->settingsBusy()) state = QCoreApplication::translate("ChatGui", "Applying settings…");
+    else if (!engine->captureAvailable()) state = QCoreApplication::translate("ChatGui", "Microphone unavailable");
+    else if (engine->vadEnabled() && !engine->vadAvailable()) state = QCoreApplication::translate("ChatGui", "VAD unavailable");
+    else if (transmitting) state = QCoreApplication::translate("ChatGui", "Transmitting");
+    else state = engine->vadEnabled() ? QCoreApplication::translate("ChatGui", "VAD listening") : QCoreApplication::translate("ChatGui", "Receiving");
    m_status->setText(state);
    m_status->setToolTip(engine->settingsError().isEmpty() ? state : engine->settingsError());
-    m_vad->setToolTip(engine->vadEnabled() ? QStringLiteral("Выключить автоматическую передачу по голосу")
-                                          : QStringLiteral("Включить автоматическую передачу по голосу"));
+    m_vad->setToolTip(engine->vadEnabled() ? QCoreApplication::translate("ChatGui", "Disable automatic voice transmission")
+                                          : QCoreApplication::translate("ChatGui", "Enable automatic voice transmission"));
 }

 /* Список перечитывается при открытии меню: подключённые устройства видны без перезапуска. */
@@ -107,7 +108,7 @@ void RadioPanel::populateDevices(QToolButton* button, bool capture) {
        group->addAction(action);
        connect(action, &QAction::triggered, this, [this, id, capture]() { selectDevice(id, capture); });
    };
-    add(QStringLiteral("По умолчанию (авто)"), QString());
+    add(QCoreApplication::translate("ChatGui", "Default (auto)"), QString());
    auto devices = capture ? SoundManager::enumerateCaptureDevices() : SoundManager::enumeratePlaybackDevices();
    for (const auto& device : devices) add(device.name, device.id);
 }
@@ -116,7 +117,7 @@ void RadioPanel::selectDevice(const QString& id, bool capture) {
    auto* inst = gui_bridge_get_inst();
    if (!inst || !gui_bridge_is_uasync_ready()) {
        DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioPanel: cannot save device: core unavailable");
-        m_status->setText(QStringLiteral("Ядро недоступно"));
+        m_status->setText(QCoreApplication::translate("ChatGui", "Core unavailable"));
        return;
    }
    const char* key = capture ? "audio_input_id" : "audio_output_id";
@@ -124,14 +125,14 @@ void RadioPanel::selectDevice(const QString& id, bool capture) {
    auto* request = static_cast<save_ui_state_arg*>(u_calloc(1, sizeof(save_ui_state_arg)));
    if (!request) {
        DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioPanel: device settings allocation failed");
-        m_status->setText(QStringLiteral("Не удалось выбрать устройство"));
+        m_status->setText(QCoreApplication::translate("ChatGui", "Failed to select device"));
        return;
    }
    size_t keyLen = strlen(key), valueLen = value.size();
    if (keyLen + valueLen + 2 > sizeof(request->data)) {
        DEBUG_ERROR(DEBUG_CATEGORY_RADIO, "RadioPanel: device ID too long bytes=%zu", valueLen);
        u_free(request);
-        m_status->setText(QStringLiteral("Не удалось выбрать устройство"));
+        m_status->setText(QCoreApplication::translate("ChatGui", "Failed to select device"));
        return;
    }
    request->inst = inst;
@@ -148,9 +149,9 @@ void RadioPanel::updateDevices() {
    for (auto* button : {m_input, m_output}) {
        bool capture = button == m_input;
        QString id = capture ? manager->captureDevice() : manager->playbackDevice();
-        QString name = QStringLiteral("По умолчанию (авто)");
+        QString name = QCoreApplication::translate("ChatGui", "Default (auto)");
        if (!id.isEmpty()) {
-            name = QStringLiteral("Выбранное устройство недоступно; используется доступное");
+            name = QCoreApplication::translate("ChatGui", "Selected device unavailable; using an available device");
            auto devices = capture ? manager->enumerateCaptureDevices() : manager->enumeratePlaybackDevices();
            for (const auto& device : devices) if (device.id == id) { name = device.name; break; }
        }
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "radiosettingspage.h"
 #include "ptt_hotkey_manager.h"
 #include "radio_audio_engine.h"
@@ -17,7 +18,7 @@

 RadioSettingsPage::RadioSettingsPage(DbManager* db, QWidget* parent) : QWidget(parent), m_db(db) {
    auto* layout = new QVBoxLayout(this);
-    auto* title = new QLabel("Рация (PTT)", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "Radio (PTT)"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);
    m_audioSettings = new QWidget(this);
@@ -30,16 +31,20 @@ RadioSettingsPage::RadioSettingsPage(DbManager* db, QWidget* parent) : QWidget(p
        form->addRow(label, spin);
        return spin;
    };
-    m_threshold = add(QStringLiteral("Порог речи VAD:"), 10, 95, QStringLiteral(" %"));
-    m_threshold->setToolTip(QStringLiteral("Порог вероятности речи: меньше — чувствительнее. Это не порог громкости."));
-    m_hangover = add(QStringLiteral("Тишина до окончания передачи:"), 50, 2000, QStringLiteral(" мс"));
-    m_compressor = new QCheckBox(QStringLiteral("Компрессор передачи и VAD"), m_audioSettings);
+    m_threshold = add(QCoreApplication::translate("ChatGui", "VAD speech threshold:"), 10, 95, QStringLiteral(" %"));
+    m_threshold->setToolTip(QCoreApplication::translate("ChatGui",
+        "Speech probability threshold: lower is more sensitive. This is not a volume threshold."));
+    m_hangover = add(QCoreApplication::translate("ChatGui",
+        "Silence before ending transmission:"), 50, 2000, QCoreApplication::translate("ChatGui",
+        " ms"));
+    m_compressor = new QCheckBox(QCoreApplication::translate("ChatGui", "Transmission and VAD compressor"), m_audioSettings);
    form->addRow(m_compressor);
-    m_txGain = add(QStringLiteral("Max gain передачи:"), 1, 60, QStringLiteral(" dB"));
-    m_vadGain = add(QStringLiteral("Max gain VAD:"), 1, 60, QStringLiteral(" dB"));
-    auto* explanation = new QLabel(QStringLiteral("VAD включается кнопкой на панели рации. Буфер начала речи — 0,6 с. "
-        "Компрессор VAD имеет отдельный max gain; остальные параметры общие с компрессором передачи. "
-        "Скорость нарастания усиления задаётся в разделе Audio."), m_audioSettings);
+    m_txGain = add(QCoreApplication::translate("ChatGui", "Transmission max gain:"), 1, 60, QCoreApplication::translate("ChatGui", " dB"));
+    m_vadGain = add(QCoreApplication::translate("ChatGui", "VAD max gain:"), 1, 60, QCoreApplication::translate("ChatGui", " dB"));
+    auto* explanation = new QLabel(QCoreApplication::translate("ChatGui",
+        "Enable VAD using the button on the radio panel. Speech prebuffer is 0.6 s. The VAD "
+        "compressor has a separate maximum gain; other parameters are shared with the transmission "
+        "compressor. Set the gain rise rate in Audio."), m_audioSettings);
    explanation->setWordWrap(true);
    form->addRow(explanation);
    layout->addWidget(m_audioSettings);
@@ -50,12 +55,13 @@ RadioSettingsPage::RadioSettingsPage(DbManager* db, QWidget* parent) : QWidget(p
    });
    loadAudioSettings();
    if (PttHotkeyManager::usesPortal()) {
-        auto* hint = new QLabel("Глобальные хоткеи работают из любых приложений. "
-            "Назначьте обычную клавишу с Ctrl, Shift, Alt или Win в системном окне. "
-            "Изменения сохраняются системой сразу. Во время настройки передача с клавиатуры отключена.", this);
+        auto* hint = new QLabel(QCoreApplication::translate("ChatGui",
+            "Global shortcuts work from any application. Assign a regular key with Ctrl, Shift, Alt or "
+            "Win in the system dialog. Changes are saved by the system immediately. Keyboard "
+            "transmission is disabled during setup."), this);
        hint->setWordWrap(true);
        layout->addWidget(hint);
-        auto* button = new QPushButton("Задать PTT хоткеи…", this);
+        auto* button = new QPushButton(QCoreApplication::translate("ChatGui", "Set PTT shortcuts…"), this);
        layout->addWidget(button);
        m_buttons << button;
        for (int i = 0; i < 3; i++) {
@@ -75,23 +81,27 @@ RadioSettingsPage::RadioSettingsPage(DbManager* db, QWidget* parent) : QWidget(p
        return;
    }
    auto* hint = new QLabel(
-        "Удерживайте сочетание для передачи из любого приложения — даже когда ChatGUI не в фокусе. "
-        "Рация канала должна быть включена. Для записи зажмите нужные клавиши вместе и отпустите их. "
-        "Левые и правые Ctrl, Shift, Alt, Win различаются. Fn доступна, только если клавиатура передаёт её ОС.", this);
+        QCoreApplication::translate("ChatGui",
+            "Hold a shortcut to transmit from any application, even when ChatGUI is not focused. "
+            "Channel radio must be enabled. To record a shortcut, hold the desired keys together and "
+            "release them. Left and right Ctrl, Shift, Alt and Win are distinct. Fn is available only "
+            "if the keyboard reports it to the OS."), this);
    hint->setWordWrap(true);
    hint->setStyleSheet("color: gray; font-size: 11px;");
    layout->addWidget(hint);
    if (!PttHotkeyManager::isSupported()) {
-        auto* warn = new QLabel("Глобальные хоткеи доступны на Windows и Linux/X11. На этой платформе запись недоступна.", this);
+        auto* warn = new QLabel(QCoreApplication::translate("ChatGui",
+            "Global shortcuts are available on Windows and Linux/X11. Shortcut recording is "
+            "unavailable on this platform."), this);
        warn->setWordWrap(true);
        warn->setStyleSheet("color: #e74c3c; font-size: 12px;");
        layout->addWidget(warn);
    }
    for (int i = 0; i < 3; i++) {
        auto* row = new QHBoxLayout();
-        auto* button = new QPushButton(QString("Задать PTT хоткей %1").arg(i + 1), this);
+        auto* button = new QPushButton(QCoreApplication::translate("ChatGui", "Set PTT shortcut %1").arg(i + 1), this);
        button->setEnabled(PttHotkeyManager::isSupported());
-        auto* clear = new QPushButton("Очистить", this);
+        auto* clear = new QPushButton(QCoreApplication::translate("ChatGui", "Clear"), this);
        row->addWidget(button); row->addWidget(clear);
        layout->addLayout(row);
        auto* label = new QLabel(this);
@@ -127,13 +137,13 @@ RadioSettingsPage::~RadioSettingsPage() {
 void RadioSettingsPage::startCapture(int index) {
    finishCapture(false);
    if (!PttHotkeyManager::instance()->beginCapture()) {
-        m_labels[index]->setText("Не удалось начать запись клавиш. Подробности в логе radio.");
+        m_labels[index]->setText(QCoreApplication::translate("ChatGui", "Failed to start key recording. See the radio log for details."));
        return;
    }
    m_captureIndex = index;
    m_capture.candidate.clear();
-    m_buttons[index]->setText("Отменить запись");
-    m_labels[index]->setText("Нажмите одну или несколько клавиш вместе…");
+    m_buttons[index]->setText(QCoreApplication::translate("ChatGui", "Cancel recording"));
+    m_labels[index]->setText(QCoreApplication::translate("ChatGui", "Press one or more keys together…"));
    qApp->installEventFilter(this);
 }

@@ -147,7 +157,7 @@ void RadioSettingsPage::finishCapture(bool save) {
    m_captureIndex = -1;
    qApp->removeEventFilter(this);
    PttHotkeyManager::instance()->endCapture();
-    m_buttons[index]->setText(QString("Задать PTT хоткей %1").arg(index + 1));
+    m_buttons[index]->setText(QCoreApplication::translate("ChatGui", "Set PTT shortcut %1").arg(index + 1));
    updateLabel(index);
 }

@@ -223,7 +233,9 @@ void RadioSettingsPage::updatePortalLabels() {
    const auto descriptions = manager->portalDescriptions();
    for (int i = 0; i < m_labels.size(); i++) {
        QString text = descriptions.value(i);
-        m_labels[i]->setText(QString("PTT хоткей %1: %2").arg(i + 1).arg(text.isEmpty() ? "Не задано" : text));
+        m_labels[i]->setText(QCoreApplication::translate("ChatGui",
+            "PTT shortcut %1: %2").arg(i + 1).arg(text.isEmpty() ? QCoreApplication::translate("ChatGui",
+            "Not set") : text));
    }
    m_portalStatus->setText(manager->portalStatus());
    m_buttons[0]->setEnabled(!manager->portalBusy());
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "renamedialog.h"
 #include "../db/db_manager.h"
 #include <QVBoxLayout>
@@ -13,7 +14,7 @@ RenameDialog::RenameDialog(DbManager* db, const QString& channelId,
    , m_channelId(channelId)
    , m_nodeId(nodeId)
 {
-    setWindowTitle("Rename");
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Rename"));
    setMinimumWidth(300);
    setModal(true);

@@ -50,8 +51,8 @@ RenameDialog::RenameDialog(DbManager* db, const QString& channelId,
    auto* btnLayout = new QHBoxLayout();
    btnLayout->addStretch();

-    auto* cancelBtn = new QPushButton("Cancel", this);
-    cancelBtn->setFixedWidth(90);
+    auto* cancelBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Cancel"), this);
+    cancelBtn->setMinimumWidth(90);
    cancelBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -59,8 +60,8 @@ RenameDialog::RenameDialog(DbManager* db, const QString& channelId,
    connect(cancelBtn, &QPushButton::clicked, this, &QDialog::reject);
    btnLayout->addWidget(cancelBtn);

-    auto* saveBtn = new QPushButton("Save", this);
-    saveBtn->setFixedWidth(90);
+    auto* saveBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Save"), this);
+    saveBtn->setMinimumWidth(90);
    saveBtn->setDefault(true);
    saveBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 4px;"
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 // settingsdialog.cpp — Settings dialog with category list
 #include "settingsdialog.h"
 #include "networksettingspage.h"
@@ -14,6 +15,9 @@
 #include "../../lib/mem.h"
 #include "../db/db_manager.h"
 #include "../transport/utun_node.h"
+#include "../transport/node_config.h"
+#include "../transport/config_updater.h"
+#include "../../lib/debug_config.h"
 extern "C" {
 #include "chat/chat_core.h"
 }
@@ -33,7 +37,7 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
    : QDialog(parent)
    , m_configPath(configPath)
 {
-    setWindowTitle("Settings");
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Settings"));
    setMinimumSize(760, 460);
    setWindowModality(Qt::WindowModal);

@@ -49,16 +53,16 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
        " background: palette(window); font-size: 13px; }"
        "QListWidget::item { padding: 10px 14px; }"
        "QListWidget::item:selected { background: #3390EC; color: white; }");
-    m_categoryList->addItem("Profile");
-    m_categoryList->addItem("Storage");
-    m_categoryList->addItem("Network");
-    m_categoryList->addItem("Connections");
-    m_categoryList->addItem("Database");
-    m_categoryList->addItem("Status");
-    m_categoryList->addItem("Nodes");
-    m_categoryList->addItem("Sound");
-    m_categoryList->addItem("Audio");
-    m_categoryList->addItem("Рация");
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Profile"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Storage"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Network"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Connections"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Database"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Status"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Nodes"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Sound"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Audio"));
+    m_categoryList->addItem(QCoreApplication::translate("ChatGui", "Radio"));
    mainLayout->addWidget(m_categoryList);

    // --- Right panel: stacked pages ---
@@ -73,35 +77,50 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
    auto* profilePage = new QWidget(m_pages);
    auto* profLayout = new QFormLayout(profilePage);
    profLayout->setContentsMargins(0, 12, 0, 0);
-    auto* nameLabel = new QLabel("Display name:", profilePage);
+    auto* nameLabel = new QLabel(QCoreApplication::translate("ChatGui", "Display name:"), profilePage);
    m_nicknameEdit = new QLineEdit(profilePage);
-    m_nicknameEdit->setPlaceholderText("Your name (shown to others)");
+    m_nicknameEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Your name (shown to others)"));
    m_nicknameEdit->setMaxLength(32);
    m_nicknameEdit->setStyleSheet(
        "QLineEdit { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 10px; font-size: 13px; background: palette(base); }");
    profLayout->addRow(nameLabel, m_nicknameEdit);

-    auto* sortLabel = new QLabel("Channel sorting:", profilePage);
+    m_languageCombo = new QComboBox(profilePage);
+    m_languageCombo->setObjectName(QStringLiteral("languageCombo"));
+    m_languageCombo->addItem(QCoreApplication::translate("ChatGui", "System language"), QStringLiteral("system"));
+    m_languageCombo->addItem(QStringLiteral("English"), QStringLiteral("en"));
+    m_languageCombo->addItem(QStringLiteral("Русский"), QStringLiteral("ru"));
+    NodeConfig languageConfig(m_configPath);
+    if (!languageConfig.load()) {
+        DEBUG_WARN(DEBUG_CATEGORY_CONFIG, "GUI language: cannot read preferences from %s", qPrintable(m_configPath));
+    }
+    m_languageCombo->setCurrentIndex(m_languageCombo->findData(languageConfig.language()));
+    profLayout->addRow(QCoreApplication::translate("ChatGui", "Interface language:"), m_languageCombo);
+    auto* languageNote = new QLabel(QCoreApplication::translate("ChatGui", "Language changes take effect after restart."), profilePage);
+    languageNote->setWordWrap(true);
+    profLayout->addRow(languageNote);
+
+    auto* sortLabel = new QLabel(QCoreApplication::translate("ChatGui", "Channel sorting:"), profilePage);
    m_sortCombo = new QComboBox(profilePage);
-    m_sortCombo->addItem("Alphabetical (A-Z)");
-    m_sortCombo->addItem("Recent Activity");
+    m_sortCombo->addItem(QCoreApplication::translate("ChatGui", "Alphabetical (A-Z)"));
+    m_sortCombo->addItem(QCoreApplication::translate("ChatGui", "Recent Activity"));
    m_sortCombo->setStyleSheet(
        "QComboBox { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 10px; font-size: 13px; background: palette(base); }");
    profLayout->addRow(sortLabel, m_sortCombo);
    
-    auto* joinLabel = new QLabel("Join requests:", profilePage);
+    auto* joinLabel = new QLabel(QCoreApplication::translate("ChatGui", "Join requests:"), profilePage);
    m_joinPolicyCombo = new QComboBox(profilePage);
-    m_joinPolicyCombo->addItem("Auto-join");
-    m_joinPolicyCombo->addItem("Ask before joining");
-    m_joinPolicyCombo->addItem("Deny all");
+    m_joinPolicyCombo->addItem(QCoreApplication::translate("ChatGui", "Auto-join"));
+    m_joinPolicyCombo->addItem(QCoreApplication::translate("ChatGui", "Ask before joining"));
+    m_joinPolicyCombo->addItem(QCoreApplication::translate("ChatGui", "Deny all"));
    m_joinPolicyCombo->setStyleSheet(
        "QComboBox { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 10px; font-size: 13px; background: palette(base); }");
    profLayout->addRow(joinLabel, m_joinPolicyCombo);

-    m_autoConnectCheck = new QCheckBox("Auto-connect to group nodes", profilePage);
+    m_autoConnectCheck = new QCheckBox(QCoreApplication::translate("ChatGui", "Auto-connect to group nodes"), profilePage);
    m_autoConnectCheck->setStyleSheet("font-size: 13px;");
    profLayout->addRow(m_autoConnectCheck);
    m_pages->addWidget(profilePage);
@@ -120,11 +139,11 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
        auto* connPage = new QWidget(m_pages);
        auto* connLayout = new QVBoxLayout(connPage);
        connLayout->setAlignment(Qt::AlignCenter);
-        auto* hintLabel = new QLabel("Live ETCP connection monitor\nwith per-link BBR statistics", connPage);
+        auto* hintLabel = new QLabel(QCoreApplication::translate("ChatGui", "Live ETCP connection monitor\nwith per-link BBR statistics"), connPage);
        hintLabel->setAlignment(Qt::AlignCenter);
        hintLabel->setStyleSheet("font-size: 12px; color: palette(text); padding: 20px;");
        connLayout->addWidget(hintLabel);
-        auto* openBtn = new QPushButton("Open Connection Monitor", connPage);
+        auto* openBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Open Connection Monitor"), connPage);
        openBtn->setStyleSheet("QPushButton { padding: 10px 20px; font-size: 13px; }");
        connect(openBtn, &QPushButton::clicked, this, &SettingsDialog::onOpenConnMonitor);
        connLayout->addWidget(openBtn);
@@ -160,8 +179,8 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
    btnLayout->setSpacing(8);
    btnLayout->addStretch();

-    auto* cancelBtn = new QPushButton("Cancel", rightPanel);
-    cancelBtn->setFixedWidth(90);
+    auto* cancelBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Cancel"), rightPanel);
+    cancelBtn->setMinimumWidth(90);
    cancelBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -169,8 +188,8 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
    connect(cancelBtn, &QPushButton::clicked, this, &QDialog::reject);
    btnLayout->addWidget(cancelBtn);

-    m_saveBtn = new QPushButton("Save", rightPanel);
-    m_saveBtn->setFixedWidth(90);
+    m_saveBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Save"), rightPanel);
+    m_saveBtn->setMinimumWidth(90);
    m_saveBtn->setDefault(true);
    m_saveBtn->setStyleSheet(
        "QPushButton { border: none; border-radius: 4px;"
@@ -299,8 +318,10 @@ void SettingsDialog::onSave() {
    m_audioDevicePage->applyAndSave();
    m_storagePage->applyAndSave();
    if (!m_radioPage->apply()) {
-        QMessageBox::warning(this, QStringLiteral("Настройки рации"), QStringLiteral("Не удалось применить настройки рации. "
-            "Проверьте доступность ядра и файла конфигурации; подробности в логе radio."));
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui",
+            "Radio settings"), QCoreApplication::translate("ChatGui",
+            "Failed to apply radio settings. Check that the core and configuration file are available; "
+            "see the radio log for details."));
        return;
    }

@@ -357,6 +378,15 @@ void SettingsDialog::onSave() {
            postChatSetting(m_configPath, "group_autoconnect", v);
        }
    }
+    const QString language = m_languageCombo->currentData().toString();
+    if (!config_update_option(m_configPath, "gui", "language", language)) {
+        DEBUG_ERROR(DEBUG_CATEGORY_CONFIG, "GUI language: failed to save preference=%s path=%s",
+                    qPrintable(language), qPrintable(m_configPath));
+        QMessageBox::warning(this, QCoreApplication::translate("ChatGui", "Settings"),
+                             QCoreApplication::translate("ChatGui", "Failed to save the interface language. Check the configuration file."));
+        return;
+    }
+    DEBUG_INFO(DEBUG_CATEGORY_CONFIG, "GUI language: saved preference=%s; applies after restart", qPrintable(language));
    accept();
 }

@@ -43,6 +43,7 @@ private:
    QPushButton*          m_saveBtn;
    QLineEdit*            m_nicknameEdit;
    QComboBox*            m_sortCombo;
+    QComboBox*            m_languageCombo;
    QComboBox*            m_joinPolicyCombo;
    QCheckBox*            m_autoConnectCheck;
    QString               m_oldNickname;
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "soundsettingspage.h"
 #include "sound_manager.h"
 #include "../db/db_manager.h"
@@ -22,12 +23,12 @@ SoundSettingsPage::SoundSettingsPage(DbManager* db, QWidget* parent)
    layout->setContentsMargins(0, 12, 0, 0);
    layout->setSpacing(14);

-    m_enabledCheck = new QCheckBox("Enable sounds", this);
+    m_enabledCheck = new QCheckBox(QCoreApplication::translate("ChatGui", "Enable sounds"), this);
    m_enabledCheck->setStyleSheet("font-size: 13px;");
    layout->addWidget(m_enabledCheck);

    auto* volLayout = new QHBoxLayout();
-    auto* volLabel = new QLabel("Volume:", this);
+    auto* volLabel = new QLabel(QCoreApplication::translate("ChatGui", "Volume:"), this);
    volLabel->setStyleSheet("font-size: 13px;");
    volLayout->addWidget(volLabel);

@@ -51,25 +52,25 @@ SoundSettingsPage::SoundSettingsPage(DbManager* db, QWidget* parent)
    sep->setStyleSheet("QFrame { color: palette(mid); }");
    layout->addWidget(sep);

-    auto* header = new QLabel("Events", this);
+    auto* header = new QLabel(QCoreApplication::translate("ChatGui", "Events"), this);
    header->setStyleSheet("font-size: 13px; font-weight: bold;");
    layout->addWidget(header);

-    m_events[0] = {"msg_incoming", "Incoming message", nullptr, nullptr, nullptr};
-    m_events[1] = {"msg_outgoing", "Outgoing message", nullptr, nullptr, nullptr};
-    m_events[2] = {"connect",     "Peer connected",  nullptr, nullptr, nullptr};
-    m_events[3] = {"disconnect",  "Peer disconnected", nullptr, nullptr, nullptr};
-    m_events[4] = {"call_incoming", "Incoming call", nullptr, nullptr, nullptr};
-    m_events[5] = {"call_connecting", "Call: connecting", nullptr, nullptr, nullptr};
-    m_events[6] = {"call_ringing", "Call: ringback", nullptr, nullptr, nullptr};
+    m_events[0] = {"msg_incoming", QT_TRANSLATE_NOOP("ChatGui", "Incoming message"), nullptr, nullptr, nullptr};
+    m_events[1] = {"msg_outgoing", QT_TRANSLATE_NOOP("ChatGui", "Outgoing message"), nullptr, nullptr, nullptr};
+    m_events[2] = {"connect",     QT_TRANSLATE_NOOP("ChatGui", "Peer connected"),  nullptr, nullptr, nullptr};
+    m_events[3] = {"disconnect",  QT_TRANSLATE_NOOP("ChatGui", "Peer disconnected"), nullptr, nullptr, nullptr};
+    m_events[4] = {"call_incoming", QT_TRANSLATE_NOOP("ChatGui", "Incoming call"), nullptr, nullptr, nullptr};
+    m_events[5] = {"call_connecting", QT_TRANSLATE_NOOP("ChatGui", "Call: connecting"), nullptr, nullptr, nullptr};
+    m_events[6] = {"call_ringing", QT_TRANSLATE_NOOP("ChatGui", "Call: ringback"), nullptr, nullptr, nullptr};

    for (int i = 0; i < 7; i++) {
        auto& e = m_events[i];
        auto* row = new QHBoxLayout();
        row->setSpacing(8);

-        auto* lbl = new QLabel(e.label, this);
-        lbl->setFixedWidth(140);
+        auto* lbl = new QLabel(QCoreApplication::translate("ChatGui", e.label), this);
+        lbl->setMinimumWidth(140);
        lbl->setStyleSheet("font-size: 13px;");
        row->addWidget(lbl);

@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 // statuspage.cpp — Status page (NTP + connections) in settings
 #include "statuspage.h"
 #include "../transport/utun_node.h"
@@ -50,7 +51,7 @@ StatusPage::StatusPage(UtunNode* node, QWidget* parent)
    layout->addWidget(m_clockFrame);

    /* ── System Status section ── */
-    auto* title = new QLabel("System Status", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "System Status"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);

@@ -60,13 +61,13 @@ StatusPage::StatusPage(UtunNode* node, QWidget* parent)
    m_textEdit->setStyleSheet(
        "QPlainTextEdit { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 8px; background: palette(base); }");
-    m_textEdit->setPlaceholderText("Click Refresh to load status");
+    m_textEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Click Refresh to load status"));
    layout->addWidget(m_textEdit, 1);

    auto* btnLayout = new QHBoxLayout();
    btnLayout->addStretch();
-    m_refreshBtn = new QPushButton("Refresh", this);
-    m_refreshBtn->setFixedWidth(90);
+    m_refreshBtn = new QPushButton(QCoreApplication::translate("ChatGui", "Refresh"), this);
+    m_refreshBtn->setMinimumWidth(90);
    m_refreshBtn->setStyleSheet(
        "QPushButton { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 16px; font-size: 13px; background: palette(button); }"
@@ -104,7 +105,7 @@ void StatusPage::updateClock() {
    if (synced)
        m_clockLabel->setText(QString("%1  [NTP ✓]").arg(t));
    else
-        m_clockLabel->setText(QString("%1  [LOCAL]").arg(t));
+        m_clockLabel->setText(QCoreApplication::translate("ChatGui", "%1  [LOCAL]").arg(t));

    int msToNext = 1000 - (corrected.time().msec());
    m_clockTimer->start(msToNext);
@@ -112,7 +113,7 @@ void StatusPage::updateClock() {

 void StatusPage::refreshStatus() {
    updateClock();
-    m_textEdit->setPlainText("Loading...");
+    m_textEdit->setPlainText(QCoreApplication::translate("ChatGui", "Loading..."));
    gui_bridge_post_uasync_fn(chat_core_collect_status_trampoline, gui_bridge_get_inst());
 }

@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "storagesettingspage.h"
 #include "../db/db_manager.h"
 #include "../transport/gui_bridge.h"
@@ -46,7 +47,7 @@ StorageSettingsPage::StorageSettingsPage(DbManager* db, QWidget* parent)
    layout->setContentsMargins(0, 12, 0, 0);
    layout->setSpacing(14);

-    auto* title = new QLabel("Media Storage", this);
+    auto* title = new QLabel(QCoreApplication::translate("ChatGui", "Media Storage"), this);
    title->setStyleSheet("font-weight: bold; font-size: 13px;");
    layout->addWidget(title);

@@ -54,27 +55,27 @@ StorageSettingsPage::StorageSettingsPage(DbManager* db, QWidget* parent)
    form->setSpacing(10);
    form->setContentsMargins(0, 8, 0, 0);

-    m_autoloadCheck = new QCheckBox("Autoload media", this);
+    m_autoloadCheck = new QCheckBox(QCoreApplication::translate("ChatGui", "Autoload media"), this);
    m_autoloadCheck->setStyleSheet("font-size: 13px;");
    form->addRow(m_autoloadCheck);

    m_autoloadMaxSize = new QSpinBox(this);
    m_autoloadMaxSize->setRange(1, 500);
-    m_autoloadMaxSize->setSuffix(" MB");
+    m_autoloadMaxSize->setSuffix(QCoreApplication::translate("ChatGui", " MB"));
    m_autoloadMaxSize->setFixedWidth(110);
    m_autoloadMaxSize->setStyleSheet(
        "QSpinBox { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 5px 8px; font-size: 13px; background: palette(base); }");
-    form->addRow("Autoload max size:", m_autoloadMaxSize);
+    form->addRow(QCoreApplication::translate("ChatGui", "Autoload max size:"), m_autoloadMaxSize);

    m_maxStorageSize = new QSpinBox(this);
    m_maxStorageSize->setRange(1, 100);
-    m_maxStorageSize->setSuffix(" GB");
+    m_maxStorageSize->setSuffix(QCoreApplication::translate("ChatGui", " GB"));
    m_maxStorageSize->setFixedWidth(110);
    m_maxStorageSize->setStyleSheet(
        "QSpinBox { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 5px 8px; font-size: 13px; background: palette(base); }");
-    form->addRow("Max storage size:", m_maxStorageSize);
+    form->addRow(QCoreApplication::translate("ChatGui", "Max storage size:"), m_maxStorageSize);

    layout->addLayout(form);

@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "videoplayer_engine.h"
 #include "sound_manager.h"
 #include "../../lib/debug_config.h"
@@ -74,10 +75,10 @@ void Worker::run() {
    };

    if (avformat_open_input(&fmt, path.toUtf8().constData(), nullptr, nullptr) != 0) {
-        worker_fail(this, QString("cannot open: %1").arg(path)); return;
+        worker_fail(this, QCoreApplication::translate("ChatGui", "cannot open: %1").arg(path)); return;
    }
    if (avformat_find_stream_info(fmt, nullptr) < 0) {
-        worker_fail(this, QString("no stream info: %1").arg(path)); cleanup(); return;
+        worker_fail(this, QCoreApplication::translate("ChatGui", "no stream info: %1").arg(path)); cleanup(); return;
    }

    for (unsigned i = 0; i < fmt->nb_streams; i++) {
@@ -85,7 +86,7 @@ void Worker::run() {
        if (p->codec_type == AVMEDIA_TYPE_VIDEO && vidx < 0) vidx = (int)i;
        else if (p->codec_type == AVMEDIA_TYPE_AUDIO && aidx < 0) aidx = (int)i;
    }
-    if (vidx < 0) { worker_fail(this, QString("no video stream: %1").arg(path)); cleanup(); return; }
+    if (vidx < 0) { worker_fail(this, QCoreApplication::translate("ChatGui", "no video stream: %1").arg(path)); cleanup(); return; }

    AVStream* vst = fmt->streams[vidx];
    int vw = vst->codecpar->width, vh = vst->codecpar->height;
@@ -131,7 +132,7 @@ void Worker::run() {
    if (aidx >= 0) {
        aframe = av_frame_alloc();
        pkt = av_packet_alloc();
-        if (!aframe || !pkt) { worker_fail(this, "alloc failed"); cleanup(); return; }
+        if (!aframe || !pkt) { worker_fail(this, QCoreApplication::translate("ChatGui", "alloc failed")); cleanup(); return; }

        while (av_read_frame(fmt, pkt) >= 0) {
            if (abort->loadRelaxed()) { av_packet_unref(pkt); cleanup(); return; }
@@ -175,11 +176,11 @@ void Worker::run() {
        vdec = avcodec_alloc_context3(vc);
        if (!vc || !vdec || avcodec_parameters_to_context(vdec, vst->codecpar) < 0 ||
            avcodec_open2(vdec, vc, nullptr) < 0) {
-            worker_fail(this, "video decoder open failed"); cleanup(); return;
+            worker_fail(this, QCoreApplication::translate("ChatGui", "video decoder open failed")); cleanup(); return;
        }
        frame = av_frame_alloc();
        pkt = av_packet_alloc();
-        if (!frame || !pkt) { worker_fail(this, "alloc failed"); cleanup(); return; }
+        if (!frame || !pkt) { worker_fail(this, QCoreApplication::translate("ChatGui", "alloc failed")); cleanup(); return; }
        /* YUVJ* (deprecated full-range) → обычный формат + явный range, чтобы
         * не ловить warning swscaler и не искажать цвета */
        AVPixelFormat srcFmt = vdec->pix_fmt;
@@ -192,7 +193,7 @@ void Worker::run() {
        }
        sws = sws_getContext(vw, vh, srcFmt, vw, vh, AV_PIX_FMT_RGB24,
                             SWS_BILINEAR, nullptr, nullptr, nullptr);
-        if (!sws) { worker_fail(this, "sws init failed"); cleanup(); return; }
+        if (!sws) { worker_fail(this, QCoreApplication::translate("ChatGui", "sws init failed")); cleanup(); return; }
        int *invTbl = nullptr, *tbl = nullptr, sr = 0, dr = 0, br = 0, ct = 0, st = 0;
        if (sws_getColorspaceDetails(sws, &invTbl, &sr, &tbl, &dr, &br, &ct, &st) >= 0)
            sws_setColorspaceDetails(sws, invTbl, srcRange, tbl, 1 /* RGB full-range */, br, ct, st);
@@ -252,7 +253,7 @@ void Worker::run() {

 void Worker::run() {
    DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "VideoEngine: built without FFmpeg");
-    emit error(QStringLiteral("видео недоступно (сборка без FFmpeg)"));
+    emit error(QCoreApplication::translate("ChatGui", "video unavailable (built without FFmpeg)"));
 }

 #endif /* HAVE_FFMPEG */
@@ -1,3 +1,4 @@
+#include <QCoreApplication>
 #include "videoplayer_window.h"
 #include "videoplayer_engine.h"
 #include "../../lib/debug_config.h"
@@ -76,7 +77,7 @@ public:
 VideoPlayerWindow::VideoPlayerWindow(QWidget* parent)
    : QWidget(parent, Qt::Window | Qt::FramelessWindowHint)
 {
-    setWindowTitle(QStringLiteral("Video"));
+    setWindowTitle(QCoreApplication::translate("ChatGui", "Video"));
    setFocusPolicy(Qt::StrongFocus);
    setMouseTracking(true);

@@ -99,7 +100,7 @@ VideoPlayerWindow::VideoPlayerWindow(QWidget* parent)
        "QSlider::handle:horizontal { width: 12px; margin: -4px 0; background: white; border-radius: 6px; }");

    m_playBtn = new QPushButton(QStringLiteral("⏸"), m_controls);
-    m_playBtn->setToolTip(QStringLiteral("Пауза"));
+    m_playBtn->setToolTip(QCoreApplication::translate("ChatGui", "Pause"));
    m_playBtn->setFixedWidth(40);
    m_slider = new QSlider(Qt::Horizontal, m_controls);
    m_slider->setStyle(new SeekSliderStyle());
@@ -115,7 +116,7 @@ VideoPlayerWindow::VideoPlayerWindow(QWidget* parent)

    /* крестик закрытия — отдельно, справа вверху */
    m_closeBtn = new QPushButton(QStringLiteral("✕"), this);
-    m_closeBtn->setToolTip(QStringLiteral("Закрыть"));
+    m_closeBtn->setToolTip(QCoreApplication::translate("ChatGui", "Close"));
    m_closeBtn->setCursor(Qt::ArrowCursor);
    m_closeBtn->setStyleSheet(
        "QPushButton { background: rgba(0,0,0,0.5); color: white; border: none; "
@@ -193,10 +194,10 @@ void VideoPlayerWindow::onStateChanged(int state) {
    VideoPlayerEngine::State s = (VideoPlayerEngine::State)state;
    if (s == VideoPlayerEngine::Playing) {
        m_playBtn->setText(QStringLiteral("⏸"));
-        m_playBtn->setToolTip(QStringLiteral("Пауза"));
+        m_playBtn->setToolTip(QCoreApplication::translate("ChatGui", "Pause"));
    } else if (s == VideoPlayerEngine::Paused || s == VideoPlayerEngine::Finished) {
        m_playBtn->setText(QStringLiteral("▶"));
-        m_playBtn->setToolTip(QStringLiteral("Играть"));
+        m_playBtn->setToolTip(QCoreApplication::translate("ChatGui", "Play"));
        showControls();
    }
 }
@@ -0,0 +1,153 @@
+#include "../src/gui_language.h"
+#include "../src/networksettingspage.h"
+#include "../transport/node_config.h"
+#include "../transport/config_updater.h"
+#include "../../../lib/debug_config.h"
+
+#include <QtTest>
+#include <QComboBox>
+#include <QDialogButtonBox>
+#include <QPushButton>
+#include <QFile>
+#include <QTemporaryDir>
+#include <QTranslator>
+#include <QXmlStreamReader>
+#include <QRegularExpression>
+
+class GuiLanguageTest : public QObject {
+    Q_OBJECT
+
+private slots:
+    void initTestCase() { debug_config_init(); }
+
+    void systemPreference() {
+        QCOMPARE(resolveGuiLanguage("system", {"ru-RU", "en-US"}), QString("ru"));
+        QCOMPARE(resolveGuiLanguage("system", {"en-GB", "ru-RU"}), QString("en"));
+        QCOMPARE(resolveGuiLanguage("system", {"de-DE", "ru_RU"}), QString("ru"));
+        QCOMPARE(resolveGuiLanguage("system", {"fr-FR"}), QString("en"));
+        QCOMPARE(resolveGuiLanguage("system", {}), QString("en"));
+        QCOMPARE(resolveGuiLanguage("ru", {"en-US"}), QString("ru"));
+        QCOMPARE(resolveGuiLanguage("en", {"ru-RU"}), QString("en"));
+    }
+
+    void preferencePersistence() {
+        QTemporaryDir directory;
+        QVERIFY(directory.isValid());
+        const QString path = directory.filePath("vibechat.cfg");
+        NodeConfig config(path);
+        QVERIFY(config.create("Language test", 1333));
+        QCOMPARE(config.language(), QString("system"));
+        for (const QString& language : {QString("ru"), QString("en"), QString("system")}) {
+            QVERIFY(config_update_option(path, "gui", "language", language));
+            QVERIFY(config.load());
+            QVERIFY2(!config.hasErrors(), qPrintable(config.errors().join('\n')));
+            QCOMPARE(config.language(), language);
+            QVERIFY(config.save());
+            NodeConfig reloaded(path);
+            QVERIFY(reloaded.load());
+            QCOMPARE(reloaded.language(), language);
+            QVERIFY(reloaded.saveFull());
+            QVERIFY(reloaded.load());
+            QCOMPARE(reloaded.language(), language);
+        }
+        QVERIFY(config_update_option(path, "gui", "language", "invalid"));
+        QVERIFY(config.load());
+        QCOMPARE(config.language(), QString("system"));
+        QVERIFY(config_update_option(path, "gui", "language", "ru"));
+        QVERIFY(config.load());
+        QFile file(path);
+        QVERIFY(file.open(QIODevice::WriteOnly | QIODevice::Truncate));
+        const QByteArray minimalConfig("[gui]\ndb_path=chat_data\n");
+        QCOMPARE(file.write(minimalConfig), qint64(minimalConfig.size()));
+        file.close();
+        QVERIFY(config.load());
+        QCOMPARE(config.language(), QString("system"));
+    }
+
+    void embeddedCatalogs() {
+        for (const QString& language : {QString("en"), QString("ru")}) {
+            QTranslator translator;
+            QVERIFY(translator.load(":/translations/chatgui_" + language + ".qm"));
+            QVERIFY(qApp->installTranslator(&translator));
+            QCOMPARE(QCoreApplication::translate("ChatGui", "Settings"), language == "ru" ? QString("Настройки") : QString("Settings"));
+            QFile file(QStringLiteral(GUI_TS_DIR) + "/chatgui_" + language + ".ts");
+            QVERIFY(file.open(QIODevice::ReadOnly));
+            QXmlStreamReader xml(&file);
+            QString source;
+            int count = 0;
+            const QRegularExpression placeholders("%(?:L?[1-9][0-9]?|n)");
+            auto parameters = [&](const QString& text) {
+                QStringList list;
+                auto matches = placeholders.globalMatch(text);
+                while (matches.hasNext()) list.append(matches.next().captured());
+                list.sort();
+                return list;
+            };
+            while (!xml.atEnd()) {
+                xml.readNext();
+                if (!xml.isStartElement()) continue;
+                if (xml.name() == QLatin1String("source")) source = xml.readElementText();
+                if (xml.name() != QLatin1String("translation")) continue;
+                QVERIFY(!xml.attributes().hasAttribute("type"));
+                const QString translation = xml.readElementText();
+                QVERIFY2(!translation.isEmpty(), qPrintable(source));
+                QCOMPARE(parameters(translation), parameters(source));
+                QCOMPARE(QCoreApplication::translate("ChatGui", source.toUtf8().constData()), translation);
+                if (language == "en") QCOMPARE(translation, source);
+                count++;
+            }
+            QVERIFY2(!xml.hasError(), qPrintable(xml.errorString()));
+            QVERIFY(count > 0);
+            qApp->removeTranslator(&translator);
+        }
+    }
+
+    void standardButtons() {
+        QTranslator translator;
+        QVERIFY(translator.load(":/translations/qtbase_ru.qm"));
+        QVERIFY(qApp->installTranslator(&translator));
+        QDialogButtonBox buttons(QDialogButtonBox::Cancel | QDialogButtonBox::Save);
+        QCOMPARE(buttons.button(QDialogButtonBox::Cancel)->text().remove('&'), QString("Отмена"));
+        QCOMPARE(buttons.button(QDialogButtonBox::Save)->text().remove('&'), QString("Сохранить"));
+        qApp->removeTranslator(&translator);
+    }
+
+    void translatedNetworkValues_data() {
+        QTest::addColumn<QString>("language");
+        QTest::newRow("English") << QString("en");
+        QTest::newRow("Russian") << QString("ru");
+    }
+
+    void translatedNetworkValues() {
+        QFETCH(QString, language);
+        QTranslator translator;
+        QVERIFY(translator.load(":/translations/chatgui_" + language + ".qm"));
+        QVERIFY(qApp->installTranslator(&translator));
+        QTemporaryDir directory;
+        QVERIFY(directory.isValid());
+        const QString path = directory.filePath("vibechat.cfg");
+        QVERIFY(config_rewrite_servers(path, {{"test", "0.0.0.0:1333", "tcp", "private", ""}}));
+        NetworkSettingsPage page;
+        page.loadFromConfig(path);
+        QComboBox* type = nullptr;
+        for (auto* combo : page.findChildren<QComboBox*>()) {
+            if (combo->findData(QString("public")) >= 0) type = combo;
+        }
+        QVERIFY(type);
+        QCOMPARE(type->currentData().toString(), QString("private"));
+        QCOMPARE(type->currentText(), language == "ru" ? QString("Частный") : QString("Private"));
+        type->setCurrentIndex(type->findData(QString("local")));
+        page.saveToConfig(path);
+        QFile file(path);
+        QVERIFY(file.open(QIODevice::ReadOnly));
+        const QByteArray content = file.readAll();
+        QVERIFY(content.contains("type=local\n"));
+        QVERIFY(content.contains("addr=0.0.0.0:1333\n"));
+        QVERIFY(content.contains("transport=tcp\n"));
+        QVERIFY(!content.contains("netif="));
+        qApp->removeTranslator(&translator);
+    }
+};
+
+QTEST_MAIN(GuiLanguageTest)
+#include "test_gui_language.moc"
@@ -159,7 +159,7 @@ int main(int argc, char** argv) {
        QTimer::singleShot(10000, &app, &QCoreApplication::quit);
        portal.initialize();
        app.exec();
-        return done && !portal.status().contains("недоступны") ? 0 : 1;
+        return done && !portal.status().contains("unavailable") ? 0 : 1;
    }
    PortalTest test;
    return QTest::qExec(&test, argc, argv);
@@ -144,7 +144,7 @@ int main(int argc, char** argv) {
    detectorAvailable = false;
    vad->click();
    await([&]() { return !engine->settingsBusy(); });
-    REQUIRE(vad->isChecked() && engine->captureAvailable() && !engine->vadAvailable() && status->text() == "VAD недоступен");
+    REQUIRE(vad->isChecked() && engine->captureAvailable() && !engine->vadAvailable() && status->text() == "VAD unavailable");
    QTest::mousePress(ptt, Qt::LeftButton);
    await([&]() { return engine->isTransmitting(); });
    QTest::mouseRelease(ptt, Qt::LeftButton);
@@ -0,0 +1,7 @@
+<RCC>
+    <qresource prefix="/translations">
+        <file alias="chatgui_en.qm">@CMAKE_CURRENT_BINARY_DIR@/translations/chatgui_en.qm</file>
+        <file alias="chatgui_ru.qm">@CMAKE_CURRENT_BINARY_DIR@/translations/chatgui_ru.qm</file>
+        <file alias="qtbase_ru.qm">@QT_RUSSIAN_CATALOG@</file>
+    </qresource>
+</RCC>
@@ -1,6 +1,7 @@
 // node_config.cpp — Simplified INI config manager for embedded uTun node
 #include "node_config.h"
 #include "config_updater.h"
+#include "../../../lib/debug_config.h"
 #include <QHostInfo>

 extern "C" {
@@ -39,7 +40,7 @@ static const QSet<QString> CONTROL_KEYS = {
 };

 static const QSet<QString> GUI_KEYS = {
-    "db_path", "debug_file", "debug_level",
+    "db_path", "debug_file", "debug_level", "language",
    "sound_dir", "sound_msg_incoming", "sound_msg_outgoing",
    "sound_connect", "sound_disconnect"
 };
@@ -225,6 +226,7 @@ bool NodeConfig::load() {
    m_servers.clear();
    m_clients.clear();
    m_errors.clear();
+    m_language = QStringLiteral("system");

    QString section, controlIp, controlPort;
    QTextStream in(&f);
@@ -336,6 +338,10 @@ bool NodeConfig::load() {
            if (key == "db_path") m_dbPath = val;
            else if (key == "debug_file") m_debugFile = val;
            else if (key == "debug_level") m_debugLevel = val;
+            else if (key == "language") {
+                if (val == "system" || val == "en" || val == "ru") m_language = val;
+                else DEBUG_WARN(DEBUG_CATEGORY_CONFIG, "GUI language: invalid preference '%s', using system language", qPrintable(val));
+            }
        } else if (debugSection) {
            if (!m_debugCategories.isEmpty()) m_debugCategories += ',';
            m_debugCategories += key + '=' + val;
@@ -386,6 +392,7 @@ bool NodeConfig::saveFull() {
    out << "[gui]\n";
    out << "db_path=" << (m_dbPath.isEmpty() ? "chat_data" : m_dbPath) << "\n";
    out << "debug_file=" << m_debugFile << "\n";
+    out << "language=" << m_language << "\n";
    out << "debug_level=" << (m_debugLevel.isEmpty() ? "info" : m_debugLevel) << "\n\n";

    out << "[debug]\n";
@@ -445,6 +452,7 @@ bool NodeConfig::save() {

    config_update_in_lines(lines, "gui", "db_path", m_dbPath.isEmpty() ? "chat_data" : m_dbPath, true);
    config_update_in_lines(lines, "gui", "debug_file", m_debugFile, true);
+    config_update_in_lines(lines, "gui", "language", m_language, true);
    config_update_in_lines(lines, "gui", "debug_level", m_debugLevel.isEmpty() ? "info" : m_debugLevel, true);

    /* [debug] section: each category=level as separate line */
@@ -54,6 +54,7 @@ public:
    void setDebugFile(const QString& p) { m_debugFile = p; }
    QString debugLevel() const { return m_debugLevel; }
    QString debugCategories() const { return m_debugCategories; }
+    QString language() const { return m_language; }

    /* Config validation errors (collected during load()) */
    bool hasErrors() const { return !m_errors.isEmpty(); }
@@ -77,6 +78,7 @@ private:
    QString m_debugFile;
    QString m_debugLevel;
    QString m_debugCategories;
+    QString m_language = QStringLiteral("system");
    QStringList m_errors;
 };
 #endif // NODE_CONFIG_H