Basic working use of resolvers for XSPF playlists.

src/CMakeLists.txt

@@ -191,6 +191,7 @@ set(SOURCES
   playlistparsers/xspfparser.cpp
 
   resolvers/libraryresolver.cpp
+  resolvers/songresolver.cpp
 
   smartplaylists/generator.cpp
   smartplaylists/generatorinserter.cpp
@@ -402,6 +403,7 @@ set(HEADERS
 
   resolvers/libraryresolver.h
   resolvers/resolver.h
+  resolvers/songresolver.h
 
   smartplaylists/generator.h
   smartplaylists/generatorinserter.h

src/playlistparsers/parserbase.cpp

@@ -19,6 +19,7 @@
 #include "library/librarybackend.h"
 #include "library/libraryquery.h"
 #include "library/sqlrow.h"
+#include "resolvers/songresolver.h"
 
 #include <QUrl>
 
@@ -31,6 +32,9 @@ ParserBase::ParserBase(LibraryBackendInterface* library, QObject *parent)
 void ParserBase::LoadSong(const QString& filename_or_url, qint64 beginning,
                           const QDir& dir, Song* song) const {
   if (filename_or_url.isEmpty()) {
+    // Try and resolve from various sources.
+    SongResolver resolver(library_);
+    resolver.ResolveSong(song);
     return;
   }
 

src/playlistparsers/xspfparser.cpp

@@ -90,13 +90,13 @@ Song XSPFParser::ParseTrack(QXmlStreamReader* reader, const QDir& dir) const {
   }
 
 return_song:
-  Song song = LoadSong(location, 0, dir);
-
-  // Override metadata with what was in the playlist
+  Song song;
   song.set_title(title);
   song.set_artist(artist);
   song.set_album(album);
   song.set_length_nanosec(nanosec);
+  LoadSong(location, 0, dir, &song);
+
   return song;
 }
 

src/resolvers/libraryresolver.cpp

@@ -22,6 +22,7 @@ int LibraryResolver::ResolveSong(const Song& song) {
   LibraryQuery* query = new LibraryQuery;
   query->AddWhere("artist", song.artist());
   query->AddWhere("title", song.title());
+  query->SetColumnSpec("%songs_table.ROWID, " + Song::kColumnSpec);
 
   QFuture<bool> future = QtConcurrent::run(
       backend_, &LibraryBackendInterface::ExecQuery, query);

src/resolvers/songresolver.cpp

@@ -0,0 +1,51 @@
+#include "songresolver.h"
+
+#include "core/logging.h"
+#include "core/song.h"
+#include "internet/internetmodel.h"
+#include "internet/spotifyservice.h"
+#include "libraryresolver.h"
+#include "spotifyresolver.h"
+
+SongResolver::SongResolver(LibraryBackendInterface* library, QObject* parent)
+    : QObject(parent),
+      song_(NULL),
+      resolvers_finished_(0),
+      resolved_(false) {
+  // Register in the other they should be checked.
+  RegisterResolver(new LibraryResolver(library));
+  RegisterResolver(new SpotifyResolver(InternetModel::Service<SpotifyService>()->server()));
+}
+
+SongResolver::~SongResolver() {
+  qDeleteAll(resolvers_);
+  resolvers_.clear();
+}
+
+void SongResolver::RegisterResolver(Resolver* resolver) {
+  resolvers_ << resolver;
+  connect(resolver, SIGNAL(ResolveFinished(int, SongList)), SLOT(ResolveFinished(int, SongList)));
+}
+
+bool SongResolver::ResolveSong(Song* song) {
+  song_ = song;
+  foreach (Resolver* resolver, resolvers_) {
+    resolver->ResolveSong(*song);
+  }
+  loop_.exec();
+  return resolved_;
+}
+
+void SongResolver::ResolveFinished(int, SongList resolved_songs) {
+  ++resolvers_finished_;
+  if (resolvers_finished_ == resolvers_.size()) {
+    loop_.quit();
+  }
+
+  if (!resolved_songs.isEmpty()) {
+    *song_ = resolved_songs.first();
+    qLog(Debug) << "Resolved song:" << song_->title() << "from:" << sender()->metaObject()->className();
+    resolved_ = true;
+    loop_.quit();
+  }
+}

src/resolvers/songresolver.h

@@ -0,0 +1,37 @@
+#ifndef SONGRESOLVER_H
+#define SONGRESOLVER_H
+
+#include <QEventLoop>
+#include <QList>
+#include <QObject>
+
+#include "core/song.h"
+
+class LibraryBackendInterface;
+class Resolver;
+
+class SongResolver : public QObject {
+  Q_OBJECT
+ public:
+  SongResolver(LibraryBackendInterface* library, QObject* parent = 0);
+  virtual ~SongResolver();
+
+  // Blocking
+  bool ResolveSong(Song* song);
+
+ private slots:
+  void ResolveFinished(int, SongList resolved_songs);
+
+ private:
+  void RegisterResolver(Resolver* resolver);
+
+  QList<Resolver*> resolvers_;
+  Song* song_;
+
+  QEventLoop loop_;
+
+  int resolvers_finished_;
+  bool resolved_;
+};
+
+#endif