Added track fetching timeouts to PlaybackService. This should skirt a

couple edge cases and possibly allow us to not immediately stop playback
when reconnecting.

src/musikcore/audio/PlaybackService.cpp

@@ -60,6 +60,12 @@ using musik::core::ILibraryPtr;
 using musik::core::audio::ITransport;
 using Editor = PlaybackService::Editor;
 
+/* internally PlaybackService leverages a message queue for synchronization;
+tracks are a special in that they are heavy-weight so aggressively exjected
+from caches... sometimes we may have to query for them. if they take more than
+the specified timeout we consider it a failure and stop playback. */
+static const size_t kTrackTimeoutMs = 3000;
+
 #define NO_POSITION (size_t) -1
 #define START_OVER (size_t) -2
 
@@ -332,13 +338,17 @@ void PlaybackService::ProcessMessage(IMessage &message) {
                 }
 
                 if (this->index != NO_POSITION) {
-                    track = this->playlist.Get(this->index);
+                    track = this->playlist.GetWithTimeout(this->index, kTrackTimeoutMs);
                 }
             }
 
             if (track) {
                 this->OnTrackChanged(this->index, track);
             }
+            else {
+                this->Stop();
+                return;
+            }
 
             if (eventType == StreamPlaying) {
                 this->PrepareNextTrack();
@@ -365,10 +375,13 @@ void PlaybackService::ProcessMessage(IMessage &message) {
             /* notify track change as soon as we're prepared. if we wait until
             we start playing, it may be a while until the UI knows to redraw! */
             if (this->UriAtIndex(this->index) == transport->Uri()) {
-                auto track = this->playlist.Get(this->index);
+                auto track = this->playlist.GetWithTimeout(this->index, kTrackTimeoutMs);
                 if (track) {
                     this->OnTrackChanged(this->index, track);
                 }
+                else {
+                    this->Stop();
+                }
             }
         }
 
@@ -589,26 +602,18 @@ bool PlaybackService::HotSwap(const TrackList& tracks, size_t index) {
     bool found = false;
     auto playingTrack = this->GetPlaying();
     if (playingTrack && tracks.Count() > index) {
-        auto supplantTrack = tracks.Get(index);
-        auto supplantLibrary = supplantTrack->Library();
         auto supplantId = tracks.GetId(index);
-
-        auto playingId = playingTrack->GetId();
-        auto playingLibrary = playingTrack->Library();
+        const auto playingId = playingTrack->GetId();
 
         /* look at the index hint, see if we can find a matching track without
         iteration. */
-        if (supplantId == playingId && supplantLibrary == playingLibrary) {
+        if (supplantId == playingId) {
             found = true;
         }
         /* otherwise search the input */
         else {
             for (size_t i = 0; i < tracks.Count(); i++) {
-                supplantTrack = tracks.Get(i);
-                auto supplantLibrary = supplantTrack->Library();
-                auto supplantId = supplantTrack->GetId();
-
-                if (supplantId == playingId && supplantLibrary == playingLibrary) {
+                if (tracks.GetId(i) == playingId) {
                     index = i;
                     found = true;
                 }
@@ -828,7 +833,7 @@ double PlaybackService::GetDuration() {
 
         size_t index = this->index;
         if (index < this->playlist.Count()) {
-            track = this->playlist.Get(index);
+            track = this->playlist.GetWithTimeout(index, kTrackTimeoutMs);
         }
     }
 
@@ -845,7 +850,7 @@ ITrack* PlaybackService::GetTrack(size_t index) {
     const size_t count = this->playlist.Count();
 
     if (count && index < this->playlist.Count()) {
-        auto track = this->playlist.Get(index);
+        auto track = this->playlist.GetWithTimeout(index, kTrackTimeoutMs * 10);
         if (track) {
             return track->GetSdkValue();
         }
@@ -876,7 +881,7 @@ TrackPtr PlaybackService::GetTrackAtIndex(size_t index) {
         return TrackPtr();
     }
 
-    return this->playlist.Get(index);
+    return this->playlist.GetWithTimeout(index, kTrackTimeoutMs);
 }
 
 Editor PlaybackService::Edit() {
@@ -1101,7 +1106,7 @@ void PlaybackService::Editor::Release() {
 
 std::string PlaybackService::UriAtIndex(size_t index) {
     if (index < this->playlist.Count()) {
-        auto track = this->playlist.Get(index);
+        auto track = this->playlist.GetWithTimeout(index, kTrackTimeoutMs);
         if (track) {
             return this->library->GetResourceLocator().GetTrackUri(track.get());
         }
@@ -1128,7 +1133,7 @@ ITransport::Gain PlaybackService::GainAtIndex(size_t index) {
     Mode mode = (Mode)playbackPrefs->GetInt(keys::ReplayGainMode.c_str(), (int) Mode::Disabled);
 
     if (mode != Mode::Disabled && index < this->playlist.Count()) {
-        auto track = this->playlist.Get(index);
+        auto track = this->playlist.GetWithTimeout(index, kTrackTimeoutMs);
         if (track) {
             auto rg = track->GetReplayGain();
             float gain = (mode == Mode::Album) ? rg.albumGain : rg.trackGain;

src/musikcore/library/track/TrackList.cpp

@@ -172,6 +172,22 @@ TrackPtr TrackList::Get(size_t index, bool async) const {
 #endif
 }
 
+TrackPtr TrackList::GetWithTimeout(size_t index, size_t timeoutMs) const {
+    auto id = this->ids.at(index);
+    auto cached = this->GetFromCache(id);
+    if (cached) { return cached; }
+
+    auto target = std::make_shared<LibraryTrack>(id, this->library);
+    auto query = std::make_shared<TrackMetadataQuery>(target, this->library);
+    this->library->EnqueueAndWait(query, timeoutMs);
+    if (query->GetStatus() == IQuery::Finished) {
+        this->AddToCache(id, query->Result());
+        return query->Result();
+    }
+
+    return TrackPtr();
+}
+
 ITrack* TrackList::GetTrack(size_t index) const {
     return this->Get(index)->GetSdkValue();
 }

src/musikcore/library/track/TrackList.h

@@ -79,8 +79,7 @@ namespace musik { namespace core {
 
             /* implementation specific */
             TrackPtr Get(size_t index, bool async = false) const;
-            TrackPtr GetSync(size_t index) const { return this->Get(index, false); }
-            TrackPtr GetAsync(size_t index) const { return this->Get(index, true); }
+            TrackPtr GetWithTimeout(size_t index, size_t timeoutMs) const;
             void ClearCache();
             void Swap(TrackList& list);
             void CopyFrom(const TrackList& from);

src/musikcube/app/layout/MainLayout.cpp

@@ -292,16 +292,11 @@ void MainLayout::SwitchToLibraryLayout() {
 
 void MainLayout::OnLibraryConnectionStateChanged(ILibrary::ConnectionState state) {
     auto currentLayout = this->GetLayout();
-
     if (currentLayout == this->libraryLayout ||
         currentLayout == this->libraryNotConnectedLayout)
     {
         this->SwitchToLibraryLayout();
     }
-
-    if (state == ILibrary::ConnectionState::Disconnected) {
-        this->playback.Stop();
-    }
 }
 
 void MainLayout::OnLibraryChanged(musik::core::ILibraryPtr prev, musik::core::ILibraryPtr curr) {

src/musikcube/app/window/TrackListView.cpp

@@ -93,6 +93,7 @@ TrackListView::TrackListView(
     this->decorator = decorator;
     this->trackNumType = TrackRowRenderers::TrackNumType::Metadata;
     this->renderer = TrackRowRenderers::Get(TrackRowRenderers::Type::AlbumSort);
+    this->playing = playback.GetPlaying();
 }
 
 TrackListView::~TrackListView() {

src/musikcube/app/window/TransportWindow.cpp

@@ -373,6 +373,7 @@ TransportWindow::TransportWindow(
     this->repeatPos.y = 1;
     this->volumePos.y = 1;
     this->timePos.y = 1;
+    this->currentTrack = playback.GetPlaying();
     this->UpdateReplayGainState();
 }