chatgui: нативный move/resize (Wayland) + фикс замирания видео при перемотке

- окно: startSystemMove/startSystemResize вместо ручного move/setGeometry
  (Wayland игнорирует позицию окна) — драг и resize за левый/верхний край работают
- пропорции: снэп к videoAspect после нативного resize (дебаунс 150мс)
- перемотка: backpressure по m_buffered (декод не убегает вперёд и воркер живёт
  для seek), seek через av_seek_frame(-1, us), пропуск кадров с AV_NOPTS_VALUE
- SeekSlider: клик по шкале = прыжок к позиции
- крестик закрытия справа вверху; курсор контролов — стрелка
- test_video_engine: проверка seek

tools/chatgui/src/videoplayer_engine.cpp

@@ -18,7 +18,7 @@ extern "C" {
 }
 #endif
 
-static const int kMaxInFlight = 24;
+static const int kMaxBuffered = 30;
 
 /* ── Worker: демюкс + декод в отдельном потоке ── */
 
@@ -30,7 +30,7 @@ public:
     QAtomicInt* paused = nullptr;
     QAtomicInt* seekReq = nullptr;
     QAtomicInteger<qint64>* seekTargetMs = nullptr;
-    QAtomicInt* inFlight = nullptr;
+    QAtomicInt* buffered = nullptr;
     QAtomicInt* epoch = nullptr;
 
 signals:
@@ -184,35 +184,45 @@ void Worker::run() {
                              SWS_BILINEAR, nullptr, nullptr, nullptr);
         if (!sws) { worker_fail(this, "sws init failed"); cleanup(); return; }
 
+        int gen = epoch->loadRelaxed();
         auto emitFrame = [&](AVFrame* fr) {
+            if (fr->pts == AV_NOPTS_VALUE) return;  /* кадр без pts ломает очередь */
             QImage img(vw, vh, QImage::Format_RGB888);
             uint8_t* dst[1] = { img.bits() };
             int dstStride[1] = { (int)img.bytesPerLine() };
             sws_scale(sws, fr->data, fr->linesize, 0, vh, dst, dstStride);
             qint64 ptsMs = av_rescale_q(fr->pts, vst->time_base, AVRational{1, 1000});
-            inFlight->fetchAndAddRelaxed(1);
-            emit frameDecoded(img, ptsMs, epoch->loadRelaxed());
+            buffered->fetchAndAddRelaxed(1);
+            emit frameDecoded(img, ptsMs, gen);
         };
 
         bool eof = false;
-        while (!abort->loadRelaxed() && !eof) {
+        while (!abort->loadRelaxed()) {
             if (seekReq->loadRelaxed()) {
                 qint64 targetMs = seekTargetMs->loadRelaxed();
-                qint64 ts = av_rescale_q(targetMs, AVRational{1, 1000}, vst->time_base);
-                av_seek_frame(fmt, vidx, ts, AVSEEK_FLAG_BACKWARD);
+                int sret = av_seek_frame(fmt, -1, targetMs * 1000, AVSEEK_FLAG_BACKWARD);
+                if (sret < 0)
+                    DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "VideoEngine: seek to %lldms failed ret=%d",
+                                (long long)targetMs, sret);
+                else
+                    DEBUG_DEBUG(DEBUG_CATEGORY_VIDEO, "VideoEngine: seek to %lldms", (long long)targetMs);
                 avcodec_flush_buffers(vdec);
+                gen = epoch->loadRelaxed();
+                eof = false;
                 seekReq->storeRelaxed(0);
-                DEBUG_DEBUG(DEBUG_CATEGORY_VIDEO, "VideoEngine: seek to %lldms", (long long)targetMs);
             }
             if (paused->loadRelaxed()) { QThread::msleep(10); continue; }
-            if (inFlight->loadRelaxed() >= kMaxInFlight) { QThread::msleep(3); continue; }
+            if (eof) { QThread::msleep(10); continue; }  /* ждём seek или abort */
+            if (buffered->loadRelaxed() >= kMaxBuffered) { QThread::msleep(3); continue; }
 
             int ret = av_read_frame(fmt, pkt);
             if (ret < 0) {
                 avcodec_send_packet(vdec, nullptr);
                 while (avcodec_receive_frame(vdec, frame) == 0) emitFrame(frame);
                 eof = true;
-                break;
+                DEBUG_INFO(DEBUG_CATEGORY_VIDEO, "VideoEngine: decode finished");
+                emit finished();
+                continue;
             }
             if (pkt->stream_index == vidx) {
                 avcodec_send_packet(vdec, pkt);
@@ -220,11 +230,6 @@ void Worker::run() {
             }
             av_packet_unref(pkt);
         }
-
-        if (!abort->loadRelaxed()) {
-            DEBUG_INFO(DEBUG_CATEGORY_VIDEO, "VideoEngine: decode finished");
-            emit finished();
-        }
     }
 
     cleanup();
@@ -258,7 +263,7 @@ void VideoPlayerEngine::open(const QString& path) {
     m_abort.storeRelaxed(0);
     m_paused.storeRelaxed(0);
     m_seekReq.storeRelaxed(0);
-    m_inFlight.storeRelaxed(0);
+    m_buffered.storeRelaxed(0);
     clearPending();
     m_renderFrame = QImage();
     m_durationMs = 0; m_positionMs = 0; m_hasAudio = false;
@@ -272,7 +277,7 @@ void VideoPlayerEngine::open(const QString& path) {
     m_worker->paused = &m_paused;
     m_worker->seekReq = &m_seekReq;
     m_worker->seekTargetMs = &m_seekTargetMs;
-    m_worker->inFlight = &m_inFlight;
+    m_worker->buffered = &m_buffered;
     m_worker->epoch = &m_epoch;
     m_worker->moveToThread(m_thread);
 
@@ -282,7 +287,6 @@ void VideoPlayerEngine::open(const QString& path) {
     connect(m_worker, &Worker::frameDecoded, this, &VideoPlayerEngine::onFrameDecoded);
     connect(m_worker, &Worker::error, this, &VideoPlayerEngine::onWorkerError);
     connect(m_worker, &Worker::finished, this, &VideoPlayerEngine::onWorkerFinished);
-    connect(m_worker, &Worker::finished, m_thread, &QThread::quit);
 
     DEBUG_INFO(DEBUG_CATEGORY_VIDEO, "VideoEngine: open %s", qPrintable(path));
     m_thread->start();
@@ -326,7 +330,6 @@ void VideoPlayerEngine::seekMs(qint64 ms) {
         m_elapsed.restart();
     }
     m_positionMs = ms;
-    m_inFlight.storeRelaxed(0);
     if (m_state == Finished) setState(Paused);
     emit positionChanged(ms);
 }
@@ -372,6 +375,7 @@ void VideoPlayerEngine::setState(State s) {
 }
 
 void VideoPlayerEngine::clearPending() {
+    m_buffered.fetchAndSubRelaxed((int)m_pending.size());
     m_pending.clear();
 }
 
@@ -414,8 +418,10 @@ void VideoPlayerEngine::onAudioDecoded(std::shared_ptr<std::vector<int16_t>> pcm
 }
 
 void VideoPlayerEngine::onFrameDecoded(const QImage& image, qint64 ptsMs, int epoch) {
-    m_inFlight.fetchAndSubRelaxed(1);
-    if (epoch != m_epoch.loadRelaxed()) return;  /* устаревший кадр после seek */
+    if (epoch != m_epoch.loadRelaxed()) {
+        m_buffered.fetchAndSubRelaxed(1);  /* устаревший кадр после seek — не будет показан */
+        return;
+    }
     m_pending.push_back({ image, ptsMs });
 }
 
@@ -442,6 +448,7 @@ void VideoPlayerEngine::presentTick() {
     while (!m_pending.empty() && m_pending.front().second <= clk) {
         show = m_pending.front().first;
         m_pending.pop_front();
+        m_buffered.fetchAndSubRelaxed(1);
         have = true;
     }
     if (have) { m_renderFrame = show; emit framePresented(); }