Implement LR current row propagation.

This means that after this commit, all core Listening Room operations
should work, for both DJs and listeners.
Optimized LR model updating so we don't reload unless stuff has really
changed.
Also added tons of debug spam and a little debug UI.

src/libtomahawk/ListeningRoom.cpp

@@ -80,6 +80,7 @@ ListeningRoom::ListeningRoom( const source_ptr& author,
     , m_lastmodified( 0 )
     , m_createdOn( 0 ) //will be set later
     , m_entries( entries )
+    , m_currentRow( -1 )
 {
     init();
 }
@@ -203,6 +204,12 @@ ListeningRoom::updateFrom( const listeningroom_ptr& other )
         isChanged = true;
     }
 
+    if ( m_currentRow != other->m_currentRow )
+    {
+        setCurrentRow( other->m_currentRow );
+        isChanged = true;
+    }
+
     //TODO: don't reload if not needed
     m_entries.clear();
     m_entries.append( other->m_entries );
@@ -361,6 +368,7 @@ ListeningRoom::addEntries( const QList< query_ptr >& queries )
     const int prevSize = m_entries.size();
 
     m_entries.append( el );
+    emit changed();
 
     pushUpdate();
 

src/libtomahawk/ListeningRoom.h

@@ -99,6 +99,7 @@ class DLLEXPORT ListeningRoom : public QObject
     Q_PROPERTY( uint createdon          READ createdOn          WRITE setCreatedOn )
     Q_PROPERTY( QVariantList entries    READ entriesV           WRITE setEntriesV )
     Q_PROPERTY( QVariantList listenerIds READ listenerIdsV      WRITE setListenerIdsV )
+    Q_PROPERTY( int currentRow          READ currentRow         WRITE setCurrentRow )
 
     friend class ::DatabaseCommand_ListeningRoomInfo;
     friend class ::ListeningRoomModel;
@@ -125,6 +126,7 @@ class DLLEXPORT ListeningRoom : public QObject
     QString guid() const            { return m_guid; }
     uint lastmodified() const       { return m_lastmodified; }
     uint createdOn() const          { return m_createdOn; }
+    int currentRow() const          { return m_currentRow; }
 
     const QList< Tomahawk::lrentry_ptr >& entries() const { return m_entries; }
 
@@ -159,6 +161,7 @@ class DLLEXPORT ListeningRoom : public QObject
     void setEntriesV( const QVariantList& l );
     void setListenerIdsV( const QVariantList& v );
     QVariantList listenerIdsV() const;
+    void setCurrentRow( int row )               { m_currentRow = row; }
     // </IGNORE>
 
     QStringList listenerIds() const { return m_listenerIds; }
@@ -235,6 +238,7 @@ private slots:
     uint m_createdOn;
     QList< Tomahawk::lrentry_ptr > m_entries;
     QStringList m_listenerIds;
+    int m_currentRow;
 
     Tomahawk::playlistinterface_ptr m_playlistInterface;
 };

src/libtomahawk/ListeningRoomModel.cpp

@@ -235,12 +235,11 @@ ListeningRoomModel::listeningRoomEntries() const
 void
 ListeningRoomModel::loadListeningRoom( const Tomahawk::listeningroom_ptr& room, bool loadEntries )
 {
+    tDebug() << "BEGIN" << Q_FUNC_INFO;
     if ( !m_listeningRoom.isNull() ) //NOTE: LR already loaded, does this ever happen?
     {
         disconnect( m_listeningRoom.data(), SIGNAL( deleted( Tomahawk::listeningroom_ptr ) ),
                     this, SIGNAL( listeningRoomDeleted() ) );
-        disconnect( m_listeningRoom.data(), SIGNAL( changed() ),
-                    this, SIGNAL( listeningRoomChanged() ) );
         disconnect( m_listeningRoom.data(), SIGNAL( changed() ),
                     this, SLOT( reload() ) );
         disconnect( m_listeningRoom.data(), SIGNAL( listenersChanged() ),
@@ -255,8 +254,6 @@ ListeningRoomModel::loadListeningRoom( const Tomahawk::listeningroom_ptr& room,
     m_listeningRoom = room;
     connect( m_listeningRoom.data(), SIGNAL( deleted( Tomahawk::listeningroom_ptr ) ),
              this, SIGNAL( listeningRoomDeleted() ) );
-    connect( m_listeningRoom.data(), SIGNAL( changed() ),
-             this, SIGNAL( listeningRoomChanged() ) );
     connect( m_listeningRoom.data(), SIGNAL( changed() ),
              this, SLOT( reload() ) );
     connect( m_listeningRoom.data(), SIGNAL( listenersChanged() ),
@@ -274,12 +271,14 @@ ListeningRoomModel::loadListeningRoom( const Tomahawk::listeningroom_ptr& room,
     }
 
     reload();
+    tDebug() << "END" << Q_FUNC_INFO;
 }
 
 
 void
 ListeningRoomModel::reloadRoomMetadata()
 {
+    tDebug() << "BEGIN" << Q_FUNC_INFO;
     setTitle( m_listeningRoom->title() );
     QString age = TomahawkUtils::ageToString( QDateTime::fromTime_t( m_listeningRoom->createdOn() ), true );
 
@@ -294,11 +293,13 @@ ListeningRoomModel::reloadRoomMetadata()
     setDescription( desc );
 
     emit listenersChanged();
+    tDebug() << "BEGIN" << Q_FUNC_INFO;
 }
 
 void
 ListeningRoomModel::reload()
 {
+    tDebug() << "BEGIN" << Q_FUNC_INFO;
     m_isLoading = true;
 
     reloadRoomMetadata();
@@ -307,12 +308,66 @@ ListeningRoomModel::reload()
     foreach ( const lrentry_ptr& p, entries )
         tDebug() << p->guid() << p->query()->track() << p->query()->artist();
 
-    clear();
-    appendEntries( entries );
+    // Since LR dbcmds are all singletons, they give all listeners the complete LR data every time,
+    // even if the actual list of tracks has not changed.
+    // To avoid unnecessary model/view reload, we make sure that we only reload if stuff has changed.
+    // It is an expensive O(n) entry-by-entry search for changes, but it surely beats clearing and
+    // reloading the whole model and view every time.
+    bool hasChanged = false;
+    if ( entries.count() != rowCount( QModelIndex() ) )
+    {
+        hasChanged = true;
+    }
+    else //could be unchanged
+    {
+        for ( int i = 0; i < entries.count(); ++i )
+        {
+            QModelIndex idx = index( i, 0, QModelIndex() );
+            if ( !idx.isValid() )
+            {
+                hasChanged = true;
+                break;
+            }
+
+            PlayableItem* item = itemFromIndex( idx );
+            if ( item && !item->lrentry().isNull() )
+            {
+                if ( item->lrentry()->query() != entries.at( i )->query() )
+                {
+                    hasChanged = true;
+                    break;
+                }
+            }
+            else
+            {
+                hasChanged = true;
+                break;
+            }
+        }
+    }
+
+    if ( hasChanged )
+    {
+        clear();
+        appendEntries( entries ); //emits signals and stuff
+        tDebug() << "done with appendEntries call from LRM::reload()";
+    }
+
+    bool hasRowChanged = false;
+    if ( currentItem().row() != m_listeningRoom->currentRow() )
+    {
+        tDebug() << "CHANGING ROW to " << m_listeningRoom->currentRow();
+        hasRowChanged = true;
+        int row = m_listeningRoom->currentRow();
+        if ( row >= 0 && row < rowCount( QModelIndex() ) )
+            setCurrentItem( index( row, 0, QModelIndex() ) );
+    }
 
-    emit listeningRoomChanged();
+    if ( hasChanged || hasRowChanged )
+        emit currentRowChanged();
 
     m_isLoading = false;
+    tDebug() << "END" << Q_FUNC_INFO;
 }
 
 
@@ -366,6 +421,7 @@ ListeningRoomModel::insertArtists( const QList< artist_ptr >& artists, int row )
 void
 ListeningRoomModel::insertQueries( const QList< query_ptr >& queries, int row )
 {
+    tDebug() << "BEGIN" << Q_FUNC_INFO;
     QList< Tomahawk::lrentry_ptr > entries;
     foreach ( const query_ptr& query, queries )
     {
@@ -381,6 +437,7 @@ ListeningRoomModel::insertQueries( const QList< query_ptr >& queries, int row )
     }
 
     insertEntriesPrivate( entries, row );
+    tDebug() << "END" << Q_FUNC_INFO;
 }
 
 
@@ -399,6 +456,7 @@ ListeningRoomModel::insertEntriesFromView( const QList< lrentry_ptr >& entries,
 void
 ListeningRoomModel::insertEntriesPrivate( const QList< lrentry_ptr >& entries, int row )
 {
+    tDebug() << "BEGIN" << Q_FUNC_INFO;
     if ( !entries.count() )
     {
         emit trackCountChanged( rowCount( QModelIndex() ) );
@@ -446,9 +504,11 @@ ListeningRoomModel::insertEntriesPrivate( const QList< lrentry_ptr >& entries, i
         emit loadingStarted();
     }
 
+    tDebug() << "some emissions in" << Q_FUNC_INFO;
     emit endInsertRows();
     emit trackCountChanged( rowCount( QModelIndex() ) );
     finishLoading();
+    tDebug() << "END" << Q_FUNC_INFO;
 }
 
 
@@ -500,3 +560,15 @@ ListeningRoomModel::removeIndex( const QModelIndex& index, bool moreToCome )
     if ( !moreToCome )
         endRoomChanges();
 }
+
+
+void
+ListeningRoomModel::setCurrentItem( const QModelIndex& index )
+{
+    PlayableModel::setCurrentItem( index );
+    if ( !m_listeningRoom.isNull() && m_listeningRoom->author() == SourceList::instance()->getLocal() )
+    {
+        m_listeningRoom->setCurrentRow( index.row() );
+        m_listeningRoom->pushUpdate();
+    }
+}

src/libtomahawk/ListeningRoomModel.h

@@ -55,9 +55,11 @@ public slots:
 
     void removeIndex( const QModelIndex& index, bool moreToCome = false );
 
+    void setCurrentItem( const QModelIndex& index );
+
 signals:
     void listeningRoomDeleted();
-    void listeningRoomChanged();
+    void currentRowChanged();
     void listenersChanged();
 
 protected:

src/libtomahawk/ViewManager.cpp

@@ -162,9 +162,18 @@ ViewManager::createPageForListeningRoom( const listeningroom_ptr& room )
     ListeningRoomModel* model = new ListeningRoomModel();
 
     model->loadListeningRoom( room );
+    if ( model->currentItem() != QModelIndex() )
+        tDebug() << Q_FUNC_INFO << "current row is "<< model->currentItem().row();
+    else
+        tDebug() << Q_FUNC_INFO << "current row is null";
+
     w->setModel( model );
     room->resolve();
 
+    if ( !w->playlistInterface().isNull() && !w->playlistInterface()->currentItem().isNull() )
+        tDebug() << Q_FUNC_INFO << "current track is "<< w->playlistInterface()->currentItem()->track();
+    else
+        tDebug() << Q_FUNC_INFO << "current track is null";
     return w;
 }
 
@@ -218,8 +227,16 @@ ViewManager::show( const Tomahawk::listeningroom_ptr& listeningRoom )
     {
         w = m_listeningRoomWidgets.value( listeningRoom ).data();
     }
-
+    if ( !w->playlistInterface().isNull() && !w->playlistInterface()->currentItem().isNull() )
+        tDebug() << Q_FUNC_INFO << "current track is "<< w->playlistInterface()->currentItem()->track();
+    else
+        tDebug() << Q_FUNC_INFO << "current track is null";
     setPage( w );
+    tDebug() << Q_FUNC_INFO << "setPage done!";
+    if ( !w->playlistInterface().isNull() && !w->playlistInterface()->currentItem().isNull() )
+        tDebug() << Q_FUNC_INFO << "current track is "<< w->playlistInterface()->currentItem()->track();
+    else
+        tDebug() << Q_FUNC_INFO << "current track is null";
     return w;
 }
 

src/libtomahawk/audio/AudioEngine.cpp

@@ -826,6 +826,7 @@ AudioEngine::setPlaylist( Tomahawk::playlistinterface_ptr playlist )
         emit playlistChanged( playlist );
         return;
     }
+    tDebug() << Q_FUNC_INFO <<( (!playlist->currentItem().isNull())? playlist->currentItem()->track() : "" );
 
     m_playlist = playlist;
     m_stopAfterTrack.clear();

src/libtomahawk/playlist/PlayableProxyModelPlaylistInterface.cpp

@@ -95,6 +95,7 @@ PlayableProxyModelPlaylistInterface::siblingItem( int itemsAway, bool readOnly )
         return result_ptr();
 
     PlayableProxyModel* proxyModel = m_proxyModel.data();
+    tDebug() << "current item is "<< proxyModel->sourceModel()->currentItem().row();
 
     while ( m_shuffleHistory.count() && m_shuffleHistory.count() >= proxyModel->rowCount() )
     {
@@ -165,6 +166,7 @@ PlayableProxyModelPlaylistInterface::siblingItem( int itemsAway, bool readOnly )
             }
         }
     }
+    tDebug() << "current item is "<< proxyModel->sourceModel()->currentItem().row();
 
     if ( !idx.isValid() && m_repeatMode == PlaylistModes::RepeatAll )
     {
@@ -180,6 +182,7 @@ PlayableProxyModelPlaylistInterface::siblingItem( int itemsAway, bool readOnly )
             idx = proxyModel->index( proxyModel->rowCount() - 1, 0 );
         }
     }
+    tDebug() << "current item is "<< proxyModel->sourceModel()->currentItem().row();
 
     // Try to find the next available PlaylistItem (with results)
     while ( idx.isValid() )
@@ -194,15 +197,18 @@ PlayableProxyModelPlaylistInterface::siblingItem( int itemsAway, bool readOnly )
                 m_shuffleHistory << item->query();
                 m_shuffleCache = QPersistentModelIndex();
             }
+            tDebug() << "current item before return is "<< proxyModel->sourceModel()->currentItem().row();
 
             return item->query()->results().at( 0 );
         }
 
         idx = proxyModel->index( idx.row() + ( itemsAway > 0 ? 1 : -1 ), 0 );
     }
+    tDebug() << "current item is "<< proxyModel->sourceModel()->currentItem().row();
 
     if ( !readOnly )
         proxyModel->setCurrentIndex( QModelIndex() );
+    tDebug() << "current item is "<< proxyModel->sourceModel()->currentItem().row();
 
     return result_ptr();
 }

src/libtomahawk/widgets/ListeningRoomCurrentTrackWidget.cpp

@@ -116,8 +116,12 @@ ListeningRoomCurrentTrackWidget::setItem( const QPersistentModelIndex& idx )
 
     unsigned int duration = q->duration();
 
-    const QPixmap sourceIcon = q->results().first()->sourceIcon( Tomahawk::Result::DropShadow, QSize( 32, 32 ) );
-    m_avatarLabel->setPixmap( sourceIcon );
+    if ( !q->results().isEmpty() &&
+         !q->results().first()->sourceIcon( Tomahawk::Result::DropShadow, QSize( 32, 32 ) ).isNull() )
+    {
+        const QPixmap sourceIcon = q->results().first()->sourceIcon( Tomahawk::Result::DropShadow, QSize( 32, 32 ) );
+        m_avatarLabel->setPixmap( sourceIcon );
+    }
 
     if ( duration > 0 )
     {