Clementine-audio-player-Mac.../src/smartplaylists/generator.h

91 lines
2.7 KiB
C++

/* This file is part of Clementine.
Copyright 2010, David Sansome <me@davidsansome.com>
Clementine is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Clementine is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Clementine. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef PLAYLISTGENERATOR_H
#define PLAYLISTGENERATOR_H
#include "playlist/playlistitem.h"
#include <memory>
class LibraryBackend;
namespace smart_playlists {
class Generator : public QObject,
public std::enable_shared_from_this<Generator> {
Q_OBJECT
public:
Generator();
static const int kDefaultLimit;
static const int kDefaultDynamicHistory;
static const int kDefaultDynamicFuture;
// Creates a new Generator of the given type
static std::shared_ptr<Generator> Create(const QString& type);
// Should be called before Load on a new Generator
void set_library(LibraryBackend* backend) { backend_ = backend; }
void set_name(const QString& name) { name_ = name; }
LibraryBackend* library() const { return backend_; }
QString name() const { return name_; }
// Name of the subclass
virtual QString type() const = 0;
// Serialises the Generator's settings
// Called on UI-thread.
virtual void Load(const QByteArray& data) = 0;
// Called on UI-thread.
virtual QByteArray Save() const = 0;
// Creates and returns a playlist
// Called from non-UI thread.
virtual PlaylistItemList Generate() = 0;
// If the generator can be used as a dynamic playlist then GenerateMore
// should return the next tracks in the sequence. The subclass should
// remember the last GetDynamicHistory() + GetDynamicFuture() tracks and
// ensure that
// the tracks returned from this method are not in that set.
virtual bool is_dynamic() const { return false; }
virtual void set_dynamic(bool dynamic) {}
// Called from non-UI thread.
virtual PlaylistItemList GenerateMore(int count) {
return PlaylistItemList();
}
virtual int GetDynamicHistory() { return kDefaultDynamicHistory; }
virtual int GetDynamicFuture() { return kDefaultDynamicFuture; }
signals:
void Error(const QString& message);
protected:
LibraryBackend* backend_;
private:
QString name_;
};
} // namespace
#include "generator_fwd.h"
#endif // PLAYLISTGENERATOR_H