Handle window close cleanly and show exit popup selection

src/audio/Audio.cpp

@@ -217,6 +217,7 @@ void Audio::startBackgroundLoading() {
             return;
         }
     }
+    loadingAbort = false;
     loadingComplete = false;
     loadedCount = 0;
     loadingThread = std::thread(&Audio::backgroundLoadingThread, this);
@@ -235,12 +236,18 @@ void Audio::backgroundLoadingThread() {
 #endif
 
     while (true) {
+        if (loadingAbort.load()) {
+            break;
+        }
         std::string path;
         {
             std::lock_guard<std::mutex> lock(pendingTracksMutex);
             if (pendingTracks.empty()) break;
             path = std::move(pendingTracks.front());
             pendingTracks.erase(pendingTracks.begin());
+            if (loadingAbort.load()) {
+                break;
+            }
         }
         AudioTrack t;
         t.path = path;
@@ -255,6 +262,10 @@ void Audio::backgroundLoadingThread() {
 #endif
         
         // Thread-safe addition to tracks
+        if (loadingAbort.load()) {
+            break;
+        }
+
         {
             std::lock_guard<std::mutex> lock(tracksMutex);
             tracks.push_back(std::move(t));
@@ -262,8 +273,12 @@ void Audio::backgroundLoadingThread() {
         
     loadedCount++;
         
-        // Small delay to prevent overwhelming the system
-        std::this_thread::sleep_for(std::chrono::milliseconds(10));
+        // Small delay to prevent overwhelming the system (unless abort requested)
+        if (!loadingAbort.load()) {
+            std::this_thread::sleep_for(std::chrono::milliseconds(10));
+        } else {
+            break;
+        }
     }
     
 #ifdef _WIN32
@@ -328,9 +343,15 @@ void Audio::playGameMusic() {
 
 void Audio::shutdown(){ 
     // Stop background loading thread first
+    loadingAbort = true;
+    {
+        std::lock_guard<std::mutex> lock(pendingTracksMutex);
+        pendingTracks.clear();
+    }
     if (loadingThread.joinable()) {
         loadingThread.join();
     }
+    loadingComplete = true;
     
     if(audioStream){ SDL_DestroyAudioStream(audioStream); audioStream=nullptr; } 
     tracks.clear(); 

src/audio/Audio.h

@@ -72,6 +72,7 @@ private:
     std::mutex tracksMutex;
     std::mutex pendingTracksMutex;
     std::atomic<bool> loadingComplete{false};
+    std::atomic<bool> loadingAbort{false};
     std::atomic<int> loadedCount{0};
 
     // SFX mixing support