Decode voice files asynchronously before starting Qt playback

tools/chatgui/src/voiceplayback.cpp

@@ -10,6 +10,10 @@ extern "C" {
 
 #include <QFile>
 #include <QDebug>
+#include <QThread>
+#include <QPointer>
+#include <QCoreApplication>
+#include <memory>
 
 static const uint32_t OPUS_MAGIC = 0x5355504F;
 
@@ -78,21 +82,41 @@ int VoicePlayer::decodeOpusFile(const QString& filePath, std::vector<int16_t>& o
     return frameCount;
 }
 
-float VoicePlayer::playOpusFile(const QString& filePath) {
-    DEBUG_DEBUG(DEBUG_CATEGORY_DEBUG, "VoicePlayer::playOpusFile: %s", qPrintable(filePath));
-    std::vector<int16_t> pcm;
-    int sampleRate, channels;
-    float duration;
-
-    if (decodeOpusFile(filePath, pcm, sampleRate, channels, duration) <= 0) {
-        DEBUG_WARN(DEBUG_CATEGORY_DEBUG, "VoicePlayer::playOpusFile: decode failed for %s", qPrintable(filePath));
-        return 0.0f;
-    }
-
-    DEBUG_DEBUG(DEBUG_CATEGORY_DEBUG, "VoicePlayer::playOpusFile: decoded %zu samples %dHz %dch %.1fs",
-               pcm.size(), sampleRate, channels, duration);
-    SoundManager::instance()->playRawPcm(pcm.data(), pcm.size() / channels, sampleRate, channels);
-    return duration;
+static unsigned s_decodeGeneration = 0; /* Только GUI-поток. */
+static bool s_decoding = false;
+
+void VoicePlayer::cancelPending() { s_decodeGeneration++; }
+
+/* Декодирование и выделение PCM выполняются в worker; GUI принимает готовый буфер. */
+void VoicePlayer::playOpusFile(const QString& filePath, QObject* context, std::function<void(float)> ready) {
+    if (s_decoding) { DEBUG_WARN(DEBUG_CATEGORY_MEDIA, "voice: decoder busy"); ready(0); return; }
+    struct Result {
+        std::shared_ptr<std::vector<int16_t>> pcm = std::make_shared<std::vector<int16_t>>();
+        int rate = 0, channels = 0;
+        float duration = 0;
+    };
+    auto result = std::make_shared<Result>();
+    unsigned generation = ++s_decodeGeneration;
+    s_decoding = true;
+    QPointer<QObject> receiver(context);
+    auto* thread = QThread::create([filePath, result]() {
+        try {
+            if (decodeOpusFile(filePath, *result->pcm, result->rate, result->channels, result->duration) <= 0)
+                result->duration = 0;
+        } catch (const std::exception& error) {
+            DEBUG_ERROR(DEBUG_CATEGORY_MEDIA, "voice: decode failed path=%s reason=%s", qPrintable(filePath), error.what());
+            result->duration = 0;
+        }
+    });
+    QObject::connect(thread, &QThread::finished, QCoreApplication::instance(), [result, receiver, ready, generation]() {
+        s_decoding = false;
+        if (!receiver || generation != s_decodeGeneration) return;
+        if (result->duration > 0) SoundManager::instance()->playRawPcm(result->pcm->data(),
+            (int)(result->pcm->size() / result->channels), result->rate, result->channels, result->pcm);
+        ready(result->duration);
+    });
+    QObject::connect(thread, &QThread::finished, thread, &QObject::deleteLater);
+    thread->start();
 }
 
 float VoicePlayer::playOpusFromReader(MediaBlockReader& reader) {

tools/chatgui/src/voiceplayback.h

@@ -3,12 +3,15 @@
 #include <QString>
 #include <vector>
 #include <cstdint>
+#include <functional>
+class QObject;
 
 class MediaBlockReader;
 
 class VoicePlayer {
 public:
-    static float playOpusFile(const QString& filePath);
+    static void playOpusFile(const QString& filePath, QObject* context, std::function<void(float)> ready);
+    static void cancelPending();
     static int decodeOpusFile(const QString& filePath, std::vector<int16_t>& outPcm,
                                 int& outSampleRate, int& outChannels, float& outDurationSec);
     static float playOpusFromReader(MediaBlockReader& reader);