chatgui: latch radio PTT on double click and release on next press

tools/chatgui/src/radiopanel.cpp

@@ -16,6 +16,7 @@ extern "C" {
 #include <QActionGroup>
 #include <QSignalBlocker>
 #include <QStyle>
+#include <QMouseEvent>
 #include <cstring>
 
 RadioPanel::RadioPanel(QWidget* parent) : QWidget(parent) {
@@ -52,13 +53,18 @@ RadioPanel::RadioPanel(QWidget* parent) : QWidget(parent) {
     m_ptt = new QPushButton(QStringLiteral("PTT"), this);
     m_ptt->setObjectName(QStringLiteral("radioPttButton"));
     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->installEventFilter(this);
     m_ptt->setFixedSize(64, 34);
     m_ptt->setStyleSheet("QPushButton[transmitting=\"true\"] { background: #27ae60; color: white; }");
     row->addWidget(m_ptt);
     auto* engine = RadioAudioEngine::instance();
-    connect(m_ptt, &QPushButton::pressed, engine, &RadioAudioEngine::talkBegin);
-    connect(m_ptt, &QPushButton::released, engine, &RadioAudioEngine::talkEnd);
+    connect(m_ptt, &QPushButton::pressed, this, [this, engine]() {
+        if (m_pttLatched) setPttLatched(false, "button-pressed");
+        else engine->talkBegin();
+    });
+    connect(m_ptt, &QPushButton::released, this, [this, engine]() {
+        if (!m_pttLatched) engine->talkEnd();
+    });
     connect(m_vad, &QPushButton::clicked, this, [this](bool checked) {
         RadioAudioEngine::instance()->applySettings({{QStringLiteral("radio_vad_enabled"), checked ? 1 : 0}});
         updateState();
@@ -69,12 +75,47 @@ RadioPanel::RadioPanel(QWidget* parent) : QWidget(parent) {
     updateDevices();
 }
 
+RadioPanel::~RadioPanel() {
+    if (m_pttLatched) setPttLatched(false, "panel-destroyed");
+}
+
+/* Второе нажатие Qt приходит как DoubleClick: не отдаём его обычному переключателю pressed. */
+bool RadioPanel::eventFilter(QObject* watched, QEvent* event) {
+    if (watched == m_ptt && event->type() == QEvent::MouseButtonDblClick && m_ptt->isEnabled()) {
+        auto* mouse = static_cast<QMouseEvent*>(event);
+        if (mouse->button() == Qt::LeftButton && m_ptt->rect().contains(mouse->pos())) {
+            setPttLatched(true, "double-click");
+            return true;
+        }
+    }
+    return QWidget::eventFilter(watched, event);
+}
+
+/* Фиксация владеет только кнопочным PTT; хоткей и автоматическая передача остаются независимыми. */
+void RadioPanel::setPttLatched(bool latched, const char* reason) {
+    if (m_pttLatched == latched) return;
+    m_pttLatched = latched;
+    auto* engine = RadioAudioEngine::instance();
+    DEBUG_INFO(DEBUG_CATEGORY_RADIO, "RadioPanel: PTT %s group=%016llx reason=%s",
+               latched ? "latched (click to release)" : "latch released", (unsigned long long)engine->groupId(), reason);
+    if (latched) engine->talkBegin();
+    else engine->talkEnd();
+    updateState();
+}
+
 void RadioPanel::updateState() {
     auto* engine = RadioAudioEngine::instance();
+    if (m_pttLatched && (!engine->isActive() || !engine->captureAvailable()))
+        setPttLatched(false, engine->isActive() ? "microphone-unavailable" : "radio-stopped");
     QSignalBlocker blocker(m_vad);
     m_vad->setChecked(engine->vadEnabled());
     m_vad->setEnabled(engine->isActive() && engine->settingsReady() && !engine->settingsBusy());
     m_ptt->setEnabled(engine->isActive() && engine->captureAvailable());
+    m_ptt->setText(m_pttLatched ? QStringLiteral("PTT \U0001F512") : QStringLiteral("PTT"));
+    m_ptt->setToolTip(m_pttLatched ? QCoreApplication::translate("ChatGui", "PTT locked. Click to release.")
+        : QCoreApplication::translate("ChatGui", "Hold to talk, or double-click to lock PTT. Click again to release. Global shortcuts also work."));
+    m_ptt->setAccessibleName(m_pttLatched ? QCoreApplication::translate("ChatGui", "PTT locked. Click to release.")
+                                        : QCoreApplication::translate("ChatGui", "Hold to talk"));
     bool transmitting = engine->isTransmitting();
     if (m_ptt->property("transmitting").toBool() != transmitting || !m_ptt->property("transmitting").isValid()) {
         m_ptt->setProperty("transmitting", transmitting);

tools/chatgui/src/radiopanel.h

@@ -12,7 +12,10 @@ class RadioPanel : public QWidget {
     Q_OBJECT
 public:
     explicit RadioPanel(QWidget* parent = nullptr);
+    ~RadioPanel() override;
 private:
+    bool eventFilter(QObject* watched, QEvent* event) override;
+    void setPttLatched(bool latched, const char* reason);
     void updateState();
     void updateDevices();
     void populateDevices(QToolButton* button, bool capture);
@@ -20,4 +23,5 @@ private:
     QToolButton *m_input, *m_output;
     QPushButton *m_vad, *m_ptt;
     QLabel* m_status;
+    bool m_pttLatched = false;
 };