Distinguish monitors with identical Qt screen names

tools/chatgui/src/stream_publish_engine.cpp

@@ -7,6 +7,8 @@
 #include <QScreen>
 #include <QRandomGenerator>
 #include <QTransform>
+#include <QJsonArray>
+#include <QJsonDocument>
 #include <thread>
 #include <mutex>
 #include <condition_variable>
@@ -33,6 +35,19 @@ namespace {
 int64_t monotonicUs() { return std::chrono::duration_cast<std::chrono::microseconds>(
     std::chrono::steady_clock::now().time_since_epoch()).count(); }
 QString text(const char* value) { return QCoreApplication::translate("ChatGui", value); }
+#ifdef HAVE_STREAM_CAPTURE
+/* Имя QScreen не уникально (например, несколько X11 screens); номер различает одинаковые дескрипторы. */
+QByteArray screenId(QScreen* screen) {
+    int duplicate = 0;
+    for (auto* other : QGuiApplication::screens()) {
+        if (other == screen) break;
+        if (other->name() == screen->name() && other->manufacturer() == screen->manufacturer()
+            && other->model() == screen->model() && other->serialNumber() == screen->serialNumber()) duplicate++;
+    }
+    return QJsonDocument(QJsonArray{screen->name(), screen->manufacturer(), screen->model(), screen->serialNumber(), duplicate})
+        .toJson(QJsonDocument::Compact);
+}
+#endif
 }
 struct StreamPublishEngine::Impl {
     struct Audio { int64_t pts = 0, created = 0; uint64_t sequence = 0; unsigned frames = 0; int16_t pcm[1920]{}; };
@@ -148,9 +163,10 @@ QList<StreamVideoSource> StreamPublishEngine::sources() {
         || qEnvironmentVariableIsSet("WAYLAND_DISPLAY")) {
         sources.push_back({StreamVideoSource::Screen, text("Screen (system selection)"), "portal", {}});
     } else {
+        int number = 0;
         for (auto* screen : QGuiApplication::screens()) {
             QSize size = screen->size() * screen->devicePixelRatio();
-            sources.push_back({StreamVideoSource::Screen, screen->name(), screen->name().toUtf8(), {}, size});
+            sources.push_back({StreamVideoSource::Screen, QStringLiteral("%1: %2").arg(++number).arg(screen->name()), screenId(screen), {}, size});
             DEBUG_DEBUG(DEBUG_CATEGORY_VIDEO, "desktop screen capability source=%s logical=%dx%d scale=%.3f pixels=%dx%d",
                 qPrintable(screen->name()), screen->size().width(), screen->size().height(), screen->devicePixelRatio(), size.width(), size.height());
         }
@@ -225,7 +241,7 @@ bool StreamPublishEngine::openSource(const StreamPublishConfig& config) {
         m->screen = std::make_unique<QScreenCapture>();
         if (config.source.id != "portal") {
             QScreen* selected = nullptr;
-            for (auto* screen : QGuiApplication::screens()) if (screen->name().toUtf8() == config.source.id) selected = screen;
+            for (auto* screen : QGuiApplication::screens()) if (screenId(screen) == config.source.id) { selected = screen; break; }
             if (!selected) { DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop screen disappeared"); return false; }
             m->screen->setScreen(selected);
         }