Add autocompletion to artist & album tags in playlist.

Thanks to christoph.gysin
Updates issue #130

src/libraryquery.cpp

@@ -56,6 +56,11 @@ void LibraryQuery::AddWhere(const QString& column, const QVariant& value) {
   }
 }
 
+void LibraryQuery::AddWhereLike(const QString& column, const QVariant& value) {
+  where_clauses_ << QString("%1 LIKE ?").arg(column);
+  bound_values_ << value;
+}
+
 void LibraryQuery::AddCompilationRequirement(bool compilation) {
   where_clauses_ << QString("effective_compilation = %1").arg(compilation ? 1 : 0);
 }

src/libraryquery.h

@@ -42,6 +42,7 @@ class LibraryQuery {
   void SetColumnSpec(const QString& spec) { column_spec_ = spec; }
   void SetOrderBy(const QString& order_by) { order_by_ = order_by; }
   void AddWhere(const QString& column, const QVariant& value);
+  void AddWhereLike(const QString& column, const QVariant& value);
   void AddCompilationRequirement(bool compilation);
 
   QSqlQuery Query(QSqlDatabase db) const;

src/mainwindow.cpp

@@ -105,6 +105,7 @@ MainWindow::MainWindow(QNetworkAccessManager* network, QWidget *parent)
 
   playlist_->IgnoreSorting(true);
   ui_.playlist->setModel(playlist_);
+  ui_.playlist->setItemDelegates(library_);
   playlist_->IgnoreSorting(false);
 
   ui_.library_view->setModel(library_sort_model_);

src/playlist.cpp

@@ -91,31 +91,31 @@ bool Playlist::set_column_value(Song& song, Playlist::Column column,
     return false;
 
   switch(column) {
-    case Playlist::Column_Title:
+    case Column_Title:
       song.set_title(value.toString());
       break;
-    case Playlist::Column_Artist:
+    case Column_Artist:
       song.set_artist(value.toString());
       break;
-    case Playlist::Column_Album:
+    case Column_Album:
       song.set_album(value.toString());
       break;
-    case Playlist::Column_AlbumArtist:
+    case Column_AlbumArtist:
       song.set_albumartist(value.toString());
       break;
-    case Playlist::Column_Composer:
+    case Column_Composer:
       song.set_composer(value.toString());
       break;
-    case Playlist::Column_Track:
+    case Column_Track:
       song.set_track(value.toInt());
       break;
-    case Playlist::Column_Disc:
+    case Column_Disc:
       song.set_disc(value.toInt());
       break;
-    case Playlist::Column_Year:
+    case Column_Year:
       song.set_year(value.toInt());
       break;
-    case Playlist::Column_Genre:
+    case Column_Genre:
       song.set_genre(value.toString());
       break;
     default:

src/playlistview.cpp

@@ -28,6 +28,8 @@
 #include <QMenu>
 #include <QScrollBar>
 #include <QDateTime>
+#include <QLineEdit>
+#include <QCompleter>
 
 #include <math.h>
 
@@ -172,6 +174,46 @@ QString FileTypeItemDelegate::displayText(const QVariant &value, const QLocale &
   }
 }
 
+QWidget* TextItemDelegate::createEditor(
+    QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const {
+  return new QLineEdit(parent);
+}
+
+QWidget* TagCompletionItemDelegate::createEditor(
+    QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const {
+  QStringList choices;
+
+  switch(column_) {
+    case Playlist::Column_Artist: {
+      choices = library_->GetBackend()->GetAllArtists();
+      break;
+    }
+    case Playlist::Column_Album: {
+      // TODO: add optimised query to library backend?
+      LibraryBackend::AlbumList albums = library_->GetBackend()->GetAllAlbums();
+      foreach(const LibraryBackend::Album& album, albums)
+        choices << album.album_name;
+      break;
+    }
+    case Playlist::Column_AlbumArtist: {
+      // TODO: get all albumartists?
+      break;
+    }
+    default:
+      break;
+  }
+
+  QLineEdit* editor = new QLineEdit(parent);
+
+  if(!choices.isEmpty()) {
+    QCompleter* completer = new QCompleter(choices, editor);
+    completer->setCaseSensitivity(Qt::CaseInsensitive);
+    editor->setCompleter(completer);
+  }
+
+  return editor;
+}
+
 
 PlaylistView::PlaylistView(QWidget *parent)
   : QTreeView(parent),
@@ -182,13 +224,6 @@ PlaylistView::PlaylistView(QWidget *parent)
     currenttrack_play_(":currenttrack_play.png"),
     currenttrack_pause_(":currenttrack_pause.png")
 {
-  setItemDelegate(new PlaylistDelegateBase(this));
-  setItemDelegateForColumn(Playlist::Column_Length, new LengthItemDelegate(this));
-  setItemDelegateForColumn(Playlist::Column_Filesize, new SizeItemDelegate(this));
-  setItemDelegateForColumn(Playlist::Column_Filetype, new FileTypeItemDelegate(this));
-  setItemDelegateForColumn(Playlist::Column_DateCreated, new DateItemDelegate(this));
-  setItemDelegateForColumn(Playlist::Column_DateModified, new DateItemDelegate(this));
-
   setHeader(new PlaylistHeader(Qt::Horizontal, this));
   header()->setMovable(true);
 
@@ -201,6 +236,22 @@ PlaylistView::PlaylistView(QWidget *parent)
   setAlternatingRowColors(true);
 }
 
+void PlaylistView::setItemDelegates(Library* library) {
+  setItemDelegate(new PlaylistDelegateBase(this));
+  setItemDelegateForColumn(Playlist::Column_Title, new TextItemDelegate(this));
+  setItemDelegateForColumn(Playlist::Column_Album,
+      new TagCompletionItemDelegate(this, library, Playlist::Column_Album));
+  setItemDelegateForColumn(Playlist::Column_Artist,
+      new TagCompletionItemDelegate(this, library, Playlist::Column_Artist));
+  setItemDelegateForColumn(Playlist::Column_AlbumArtist,
+      new TagCompletionItemDelegate(this, library, Playlist::Column_AlbumArtist));
+  setItemDelegateForColumn(Playlist::Column_Length, new LengthItemDelegate(this));
+  setItemDelegateForColumn(Playlist::Column_Filesize, new SizeItemDelegate(this));
+  setItemDelegateForColumn(Playlist::Column_Filetype, new FileTypeItemDelegate(this));
+  setItemDelegateForColumn(Playlist::Column_DateCreated, new DateItemDelegate(this));
+  setItemDelegateForColumn(Playlist::Column_DateModified, new DateItemDelegate(this));
+}
+
 void PlaylistView::setModel(QAbstractItemModel *model) {
   QTreeView::setModel(model);
   LoadGeometry();

src/playlistview.h

@@ -17,6 +17,9 @@
 #ifndef PLAYLISTVIEW_H
 #define PLAYLISTVIEW_H
 
+#include "playlist.h"
+#include "library.h"
+
 #include <QStyledItemDelegate>
 #include <QTreeView>
 
@@ -59,6 +62,26 @@ class FileTypeItemDelegate : public PlaylistDelegateBase {
   QString displayText(const QVariant& value, const QLocale& locale) const;
 };
 
+class TextItemDelegate : public PlaylistDelegateBase {
+ public:
+  TextItemDelegate(QTreeView* view) : PlaylistDelegateBase(view) {};
+  QWidget* createEditor(QWidget* parent, const QStyleOptionViewItem& option,
+      const QModelIndex& index) const;
+};
+
+class TagCompletionItemDelegate : public PlaylistDelegateBase {
+ public:
+  TagCompletionItemDelegate(QTreeView* view, Library* library, Playlist::Column column) :
+    PlaylistDelegateBase(view), library_(library), column_(column) {};
+
+  QWidget* createEditor(QWidget* parent, const QStyleOptionViewItem& option,
+      const QModelIndex& index) const;
+
+ private:
+  Library* library_;
+  Playlist::Column column_;
+};
+
 
 class PlaylistView : public QTreeView {
   Q_OBJECT
@@ -66,6 +89,7 @@ class PlaylistView : public QTreeView {
  public:
   PlaylistView(QWidget* parent = 0);
 
+  void setItemDelegates(Library* library);
   void RemoveSelected();
 
   // QTreeView