Apply the selected language immediately in first-run setup

tools/chatgui/src/main.cpp

@@ -11,6 +11,7 @@
 #include <QLockFile>
 #include <QMessageBox>
 #include <QTranslator>
+#include <QComboBox>
 #include <QDialogButtonBox>
 #include <QHostInfo>
 #include <QLabel>
@@ -190,17 +191,23 @@ int main(int argc, char *argv[]) {
     }
 
     QTranslator guiTranslator, qtTranslator;
-    const QString language = resolveGuiLanguage(cfg.language());
+    auto loadLanguage = [&](const QString& selected) {
-    if (!guiTranslator.load(":/translations/chatgui_" + language + ".qm") || !app.installTranslator(&guiTranslator)) {
+        app.removeTranslator(&guiTranslator);
-        DEBUG_ERROR(DEBUG_CATEGORY_CONFIG, "GUI language: failed to load embedded catalog for %s", qPrintable(language));
+        app.removeTranslator(&qtTranslator);
-        return 1;
+        if (!guiTranslator.load(":/translations/chatgui_" + selected + ".qm") || !app.installTranslator(&guiTranslator)) {
-    }
+            DEBUG_ERROR(DEBUG_CATEGORY_CONFIG, "GUI language: failed to load embedded catalog for %s", qPrintable(selected));
-    if (language == "ru") {
+            return false;
-        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 (selected == "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 false;
+            }
+        }
+        return true;
+    };
+    QString language = resolveGuiLanguage(cfg.language());
+    if (!loadLanguage(language)) return 1;
     if (!locked) {
         QMessageBox::warning(nullptr, "vibechat", QCoreApplication::translate("ChatGui", "vibechat is already running."));
         return 1;
@@ -210,23 +217,47 @@ int main(int argc, char *argv[]) {
     const bool firstRun = !cfg.exists();
     if (firstRun) {
         QDialog wizard;
-        wizard.setWindowTitle(QCoreApplication::translate("ChatGui", "Welcome to vibechat"));
         wizard.setMinimumWidth(380);
         auto* layout = new QVBoxLayout(&wizard);
-        layout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Your nickname:"), &wizard));
+        auto* languageLabel = new QLabel(QStringLiteral("Language / Язык"), &wizard);
+        layout->addWidget(languageLabel);
+        auto* languageCombo = new QComboBox(&wizard);
+        languageCombo->addItem(QString(), QStringLiteral("system"));
+        languageCombo->addItem(QStringLiteral("English"), QStringLiteral("en"));
+        languageCombo->addItem(QStringLiteral("Русский"), QStringLiteral("ru"));
+        layout->addWidget(languageCombo);
+        auto* nicknameLabel = new QLabel(&wizard);
+        layout->addWidget(nicknameLabel);
         auto* nickname = new QLineEdit(&wizard);
         nickname->setMaxLength(32);
         const QString host = QHostInfo::localHostName();
         nickname->setText(host.isEmpty() ? QStringLiteral("vibechat") : host);
         layout->addWidget(nickname);
-        auto* hint = new QLabel(QCoreApplication::translate("ChatGui", "Others will see this name. You can change it later in Settings."), &wizard);
+        auto* hint = new QLabel(&wizard);
         hint->setWordWrap(true);
         layout->addWidget(hint);
         layout->addSpacing(12);
         auto* buttons = new QDialogButtonBox(QDialogButtonBox::Cancel, &wizard);
-        auto* start = buttons->addButton(QCoreApplication::translate("ChatGui", "Start chatting"), QDialogButtonBox::AcceptRole);
+        auto* start = buttons->addButton(QString(), QDialogButtonBox::AcceptRole);
         start->setDefault(true);
         layout->addWidget(buttons);
+        auto translateWizard = [&] {
+            wizard.setWindowTitle(QCoreApplication::translate("ChatGui", "Welcome to vibechat"));
+            languageCombo->setItemText(0, QCoreApplication::translate("ChatGui", "System language"));
+            nicknameLabel->setText(QCoreApplication::translate("ChatGui", "Your nickname:"));
+            hint->setText(QCoreApplication::translate("ChatGui", "Others will see this name. You can change it later in Settings."));
+            start->setText(QCoreApplication::translate("ChatGui", "Start chatting"));
+        };
+        translateWizard();
+        bool languageReady = true;
+        QObject::connect(languageCombo, qOverload<int>(&QComboBox::currentIndexChanged), &wizard, [&](int) {
+            const QString preference = languageCombo->currentData().toString();
+            language = resolveGuiLanguage(preference);
+            languageReady = loadLanguage(language);
+            if (!languageReady) { wizard.reject(); return; }
+            translateWizard();
+            DEBUG_INFO(DEBUG_CATEGORY_CONFIG, "First-run setup: language preference=%s selected=%s", qPrintable(preference), qPrintable(language));
+        });
         QObject::connect(nickname, &QLineEdit::textChanged, &wizard, [start](const QString& text) {
             start->setEnabled(!text.trimmed().isEmpty());
         });
@@ -243,11 +274,13 @@ int main(int argc, char *argv[]) {
         QObject::connect(buttons, &QDialogButtonBox::rejected, &wizard, &QDialog::reject);
         nickname->setFocus();
         nickname->selectAll();
-        DEBUG_INFO(DEBUG_CATEGORY_CONFIG, "First-run setup: requesting nickname, config=%s", qPrintable(cfgPath));
+        DEBUG_INFO(DEBUG_CATEGORY_CONFIG, "First-run setup: requesting nickname and language, config=%s", qPrintable(cfgPath));
         if (wizard.exec() != QDialog::Accepted) {
+            if (!languageReady) return 1;
             DEBUG_INFO(DEBUG_CATEGORY_CONFIG, "First-run setup: cancelled, config not created");
             return 0;
         }
+        cfg.setLanguage(languageCombo->currentData().toString());
         if (!cfg.create(nickname->text().trimmed(), 1333)) {
             DEBUG_ERROR(DEBUG_CATEGORY_CONFIG, "First-run setup: failed to create config=%s", qPrintable(cfgPath));
             QMessageBox::critical(nullptr, wizard.windowTitle(),