Loading file in async way, in two times: fast loading files and insert them in playlist view, while loading info (tags, ...) in background thread

src/core/song.cpp

@@ -560,6 +560,24 @@ void Song::InitFromQuery(const SqlRow& q, int col) {
   #undef tofloat
 }
 
+void Song::InitFromFilePartial(const QString& filename) {
+  d->filename_ = filename;
+  // We currently rely on filename suffix to know if it's a music file or not.
+  // TODO: I know this is not satisfying, but currently, we rely on TagLib
+  // which seems to have the behavior (filename checks). Someday, it would be
+  // nice to perform some magic tests everywhere.
+  QFileInfo info(filename);
+  d->basefilename_ = info.fileName();
+  QString suffix = info.suffix().toLower();
+  if (suffix == "mp3" || suffix == "ogg" || suffix == "flac" || suffix == "mpc"
+      || suffix == "m4a" || suffix == "aac" || suffix == "wma" || suffix == "mp4"
+      || suffix == "spx" || suffix == "wav") {
+    d->valid_ = true;
+  } else {
+    d->valid_ = false;
+  }
+}
+
 #ifdef HAVE_LIBLASTFM
 void Song::InitFromLastFM(const lastfm::Track& track) {
   d->valid_ = true;

src/core/song.h

@@ -128,6 +128,7 @@ class Song {
   void Init(const QString& title, const QString& artist, const QString& album, qint64 beginning, qint64 end);
   void InitFromFile(const QString& filename, int directory_id);
   void InitFromQuery(const SqlRow& query, int col = 0);
+  void InitFromFilePartial(const QString& filename); // Just store the filename: incomplete but fast
 #ifdef HAVE_LIBLASTFM
   void InitFromLastFM(const lastfm::Track& track);
 #endif

src/core/songloader.cpp

@@ -82,6 +82,21 @@ SongLoader::Result SongLoader::Load(const QUrl& url) {
   return LoadRemote();
 }
 
+SongLoader::Result SongLoader::LoadLocalPartial(const QString& filename) {
+  qDebug() << "Fast Loading local file" << filename;
+  // First check to see if it's a directory - if so we can load all the songs
+  // inside right away.
+  if (QFileInfo(filename).isDir()) {
+    LoadLocalDirectory(filename);
+    return Success;
+  }
+  Song song;
+  song.InitFromFilePartial(filename);
+  if (song.is_valid())
+    songs_ << song;
+  return Success;
+}
+
 SongLoader::Result SongLoader::LoadLocal(const QString& filename, bool block,
                                          bool ignore_playlists) {
   qDebug() << "Loading local file" << filename;
@@ -166,8 +181,7 @@ SongLoader::Result SongLoader::LoadLocal(const QString& filename, bool block,
 
     }
   }
-
+  foreach (const Song& song, song_list) {
-  foreach(const Song& song, song_list) {
     if (song.is_valid())
       songs_ << song;
   }
@@ -175,6 +189,28 @@ SongLoader::Result SongLoader::LoadLocal(const QString& filename, bool block,
   return Success;
 }
 
+void SongLoader::EffectiveSongsLoad() {
+  for (int i = 0; i < songs_.size(); i++) {
+    Song& song = songs_[i];
+    QString filename = song.filename();
+    QFileInfo info(filename);
+
+    LibraryQuery query;
+    query.SetColumnSpec("%songs_table.ROWID, " + Song::kColumnSpec);
+    query.AddWhere("filename", info.canonicalFilePath());
+
+    if (library_->ExecQuery(&query) && query.Next()) {
+      // we may have many results when the file has many sections
+      do {
+        song.InitFromQuery(query);
+      } while(query.Next());
+    } else {
+      // it's a normal media file
+      song.InitFromFile(filename, -1);
+    }
+  }
+}
+
 void SongLoader::LoadPlaylistAndEmit(ParserBase* parser, const QString& filename) {
   LoadPlaylist(parser, filename);
   emit LoadFinished(true);
@@ -209,8 +245,7 @@ void SongLoader::LoadLocalDirectory(const QString& filename) {
                   QDirIterator::Subdirectories);
 
   while (it.hasNext()) {
-    // This is in another thread so we can do blocking calls.
+    LoadLocalPartial(it.next());
-    LoadLocal(it.next(), true, true);
   }
 
   qStableSort(songs_.begin(), songs_.end(), CompareSongs);

src/core/songloader.h

@@ -54,6 +54,9 @@ public:
 
   Result Load(const QUrl& url);
 
+  // For async load, to effectively load songs 
+  void EffectiveSongsLoad();
+
 signals:
   void LoadFinished(bool success);
 
@@ -70,6 +73,7 @@ private:
   };
 
   Result LoadLocal(const QString& filename, bool block = false, bool ignore_playlists = false);
+  Result LoadLocalPartial(const QString& filename);
   void LoadLocalDirectory(const QString& filename);
   void LoadPlaylist(ParserBase* parser, const QString& filename);
   void LoadLocalDirectoryAndEmit(const QString& filename);

src/playlist/playlist.cpp

@@ -952,6 +952,38 @@ void Playlist::InsertRadioStations(const RadioModel* model,
   InsertItems(playlist_items, pos, play_now, enqueue);
 }
 
+void Playlist::UpdateItems(const SongList& songs) {
+  qDebug() << "Updating playlist with new tracks' info";
+  foreach (const Song& song, songs) {
+    // Update current items list
+    for (int i=0; i<items_.size(); i++) {
+      PlaylistItemPtr item = items_[i];
+      if (item->Metadata().filename() == song.filename()) {
+        PlaylistItemPtr new_item;
+        if (song.id() == -1) {
+          new_item = PlaylistItemPtr(new SongPlaylistItem(song));
+        } else {
+          new_item = PlaylistItemPtr(new LibraryPlaylistItem(song));
+          library_items_by_id_.insertMulti(song.id(), new_item);
+        }
+        items_[i] = new_item;
+        emit dataChanged(index(i, 0), index(i, ColumnCount-1));
+        // Also update undo actions
+        for (int i=0; i<undo_stack_->count(); i++) {
+          QUndoCommand *undo_action = const_cast<QUndoCommand*>(undo_stack_->command(i));
+          PlaylistUndoCommands::InsertItems *undo_action_insert =
+            dynamic_cast<PlaylistUndoCommands::InsertItems*>(undo_action);
+          if (undo_action_insert) {
+            bool found_and_updated = undo_action_insert->UpdateItem(new_item);
+            if (found_and_updated) break;
+          }
+        }
+        break;
+      }
+    }
+  }
+}
+
 QMimeData* Playlist::mimeData(const QModelIndexList& indexes) const {
   QMimeData* data = new QMimeData;
 

src/playlist/playlist.h

@@ -211,6 +211,7 @@ class Playlist : public QAbstractListModel {
   void InsertUrls               (const QList<QUrl>& urls,           int pos = -1, bool play_now = false, bool enqueue = false);
   // Removes items with given indices from the playlist. This operation is not undoable.
   void RemoveItemsWithoutUndo   (const QList<int>& indices);
+  void UpdateItems              (const SongList& songs);
 
   // If this playlist contains the current item, this method will apply the "valid" flag on it.
   // If the "valid" flag is false, the song will be greyed out. Otherwise the grey color will

src/playlist/playlistundocommands.cpp

@@ -47,6 +47,17 @@ void InsertItems::undo() {
   playlist_->RemoveItemsWithoutUndo(start, items_.count());
 }
 
+bool InsertItems::UpdateItem(const PlaylistItemPtr& updated_item) {
+  for (int i=0; i<items_.size(); i++) {
+    PlaylistItemPtr item = items_[i];
+    if (item->Metadata().filename() == updated_item->Metadata().filename()) {
+      items_[i] = updated_item;
+      return true;
+    }
+  }
+  return false;
+}
+
 
 RemoveItems::RemoveItems(Playlist *playlist, int pos, int count)
   : Base(playlist)

src/playlist/playlistundocommands.h

@@ -47,6 +47,11 @@ namespace PlaylistUndoCommands {
 
     void undo();
     void redo();
+    // When load is async, items have already been pushed, so we need to update them.
+    // This function try to find the equivalent item, and replace it with the
+    // new (completely loaded) one.
+    // return true if the was found (and updated), false otherwise
+    bool UpdateItem(const PlaylistItemPtr& updated_item);
 
    private:
     PlaylistItemList items_;

src/playlist/songloaderinserter.cpp

@@ -15,6 +15,8 @@
    along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <QtConcurrentRun>
+
 #include "playlist.h"
 #include "songloaderinserter.h"
 #include "core/songloader.h"
@@ -34,6 +36,7 @@ SongLoaderInserter::SongLoaderInserter(
 
 SongLoaderInserter::~SongLoaderInserter() {
   qDeleteAll(pending_);
+  qDeleteAll(pending_async_);
 }
 
 void SongLoaderInserter::Load(Playlist *destination,
@@ -84,21 +87,44 @@ void SongLoaderInserter::PendingLoadFinished(bool success) {
   if (!loader || !pending_.contains(loader))
     return;
   pending_.remove(loader);
+  pending_async_.insert(loader);
 
   if (success)
     songs_ << loader->songs();
   else
     emit Error(tr("Error loading %1").arg(loader->url().toString()));
 
-  loader->deleteLater();
-
   task_manager_->SetTaskProgress(async_load_id_, ++async_progress_);
   if (pending_.isEmpty()) {
     task_manager_->SetTaskFinished(async_load_id_);
-    Finished();
+    async_progress_ = 0;
+    async_load_id_ = task_manager_->StartTask(tr("Loading tracks info"));
+    task_manager_->SetTaskProgress(async_load_id_, async_progress_, pending_async_.count());
+    PartiallyFinished();
   }
 }
 
+void SongLoaderInserter::PartiallyFinished() {
+  // Insert songs (that haven't been completelly loaded) to allow user to see
+  // and playing them while not loaded completely
+  if (destination_) {
+    destination_->InsertSongsOrLibraryItems(songs_, row_, play_now_, enqueue_);
+  }
+  QtConcurrent::run(this, &SongLoaderInserter::EffectiveLoad);
+}
+
+void SongLoaderInserter::EffectiveLoad() {
+  foreach (SongLoader* loader, pending_async_) {
+    loader->EffectiveSongsLoad();
+    task_manager_->SetTaskProgress(async_load_id_, ++async_progress_);
+    if(destination_) {
+      destination_->UpdateItems(loader->songs());
+    }
+    loader->deleteLater();
+  }
+  task_manager_->SetTaskFinished(async_load_id_);
+}
+
 void SongLoaderInserter::Finished() {
   if (destination_) {
     destination_->InsertSongsOrLibraryItems(songs_, row_, play_now_, enqueue_);

src/playlist/songloaderinserter.h

@@ -48,6 +48,8 @@ private slots:
   void DestinationDestroyed();
 
 private:
+  void PartiallyFinished();
+  void EffectiveLoad();
   void Finished();
 
 private:
@@ -61,6 +63,7 @@ private:
   SongList songs_;
 
   QSet<SongLoader*> pending_;
+  QSet<SongLoader*> pending_async_;
   int async_load_id_;
   int async_progress_;
   LibraryBackendInterface* library_;

tests/songloader_test.cpp

@@ -325,6 +325,7 @@ void SongLoaderTest::LoadLocalDirectory(const QString &filename) {
   QObject::connect(loader_.get(), SIGNAL(LoadFinished(bool)),
                    &loop, SLOT(quit()));
   loop.exec(QEventLoop::ExcludeUserInputEvents);
+  loader_.get()->EffectiveSongsLoad();
 
   // Check the signal was emitted with Success
   ASSERT_EQ(1, spy.count());