/*
 * Copyright 2003-2020 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef MPD_DB_UNIQUE_TAGS_HXX
#define MPD_DB_UNIQUE_TAGS_HXX

#include "tag/Type.h"

#include <string>

class Database;
struct DatabaseSelection;
template<typename Key> class RecursiveMap;
template<typename T> struct ConstBuffer;

/**
 * Walk the database and collect unique tag values.
 */
RecursiveMap<std::string>
CollectUniqueTags(const Database &db, const DatabaseSelection &selection,
		  ConstBuffer<TagType> tag_types);

#endif
