You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
62 lines
1.5 KiB
C++
62 lines
1.5 KiB
C++
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
// Copyright The Music Player Daemon Project
|
|
|
|
#ifndef MPD_TAG_FALLBACK_HXX
|
|
#define MPD_TAG_FALLBACK_HXX
|
|
|
|
#include "Type.hxx"
|
|
|
|
#include <utility>
|
|
|
|
/**
|
|
* Invoke the given function for all fallback tags of the given
|
|
* #TagType, until the function returns true (or until there are no
|
|
* more fallback tags).
|
|
*/
|
|
template<typename F>
|
|
bool
|
|
ApplyTagFallback(TagType type, F &&f) noexcept
|
|
{
|
|
if (type == TAG_ALBUM_ARTIST_SORT) {
|
|
/* fall back to "AlbumArtist", "ArtistSort" and
|
|
"Artist" if no "AlbumArtistSort" was found */
|
|
if (f(TAG_ALBUM_ARTIST))
|
|
return true;
|
|
|
|
return ApplyTagFallback(TAG_ARTIST_SORT, std::forward<F>(f));
|
|
}
|
|
|
|
if (type == TAG_ALBUM_ARTIST || type == TAG_ARTIST_SORT)
|
|
/* fall back to "Artist" if no
|
|
"AlbumArtist"/"ArtistSort" was found */
|
|
return f(TAG_ARTIST);
|
|
|
|
if (type == TAG_ALBUM_SORT)
|
|
/* fall back to "Album" if no "AlbumSort" was found */
|
|
return f(TAG_ALBUM);
|
|
|
|
if (type == TAG_TITLE_SORT)
|
|
/* fall back to "Title" if no "TitleSort" was found */
|
|
return f(TAG_TITLE);
|
|
|
|
if (type == TAG_COMPOSERSORT)
|
|
/* fall back to "Composer" if no "ComposerSort" was found */
|
|
return f(TAG_COMPOSER);
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Invoke the given function for the given #TagType and all of its
|
|
* fallback tags, until the function returns true (or until there are
|
|
* no more fallback tags).
|
|
*/
|
|
template<typename F>
|
|
bool
|
|
ApplyTagWithFallback(TagType type, F &&f) noexcept
|
|
{
|
|
return f(type) || ApplyTagFallback(type, std::forward<F>(f));
|
|
}
|
|
|
|
#endif
|