Add conversion from GetFunction to tag type

src/format.h

@@ -60,9 +60,13 @@ private:
 	unsigned m_delimiter;
 };
 
-template <typename CharT> using SongTagMap = std::vector<
+template <typename CharT>
-	std::pair<SongTag, std::basic_string<CharT> >
+using SongTagMap = std::vector<
->;
+	std::pair<
+		SongTag,
+		std::basic_string<CharT>
+		>
+	>;
 
 enum class Result { Empty, Missing, Ok };
 

src/utility/type_conversions.cpp

@@ -199,6 +199,36 @@ MPD::Song::GetFunction charToGetFunction(char c)
 	}
 }
 
+boost::optional<mpd_tag_type> getFunctionToTagType(MPD::Song::GetFunction f)
+{
+	if (f == &MPD::Song::getArtist)
+		return MPD_TAG_ARTIST;
+	else if (f == &MPD::Song::getTitle)
+		return MPD_TAG_TITLE;
+	else if (f == &MPD::Song::getAlbum)
+		return MPD_TAG_ALBUM;
+	else if (f == &MPD::Song::getAlbumArtist)
+		return MPD_TAG_ALBUM_ARTIST;
+	else if (f == &MPD::Song::getTrack)
+		return MPD_TAG_TRACK;
+	else if (f == &MPD::Song::getDate)
+		return MPD_TAG_DATE;
+	else if (f == &MPD::Song::getGenre)
+		return MPD_TAG_GENRE;
+	else if (f == &MPD::Song::getComposer)
+		return MPD_TAG_COMPOSER;
+	else if (f == &MPD::Song::getPerformer)
+		return MPD_TAG_PERFORMER;
+	else if (f == &MPD::Song::getComment)
+		return MPD_TAG_COMMENT;
+	else if (f == &MPD::Song::getDisc)
+		return MPD_TAG_DISC;
+	else if (f == &MPD::Song::getComment)
+		return MPD_TAG_COMMENT;
+	else
+		return boost::none;
+}
+
 std::string itemTypeToString(MPD::Item::Type type)
 {
 	std::string result;

src/utility/type_conversions.h

@@ -21,6 +21,8 @@
 #ifndef NCMPCPP_UTILITY_TYPE_CONVERSIONS_H
 #define NCMPCPP_UTILITY_TYPE_CONVERSIONS_H
 
+#include <boost/optional.hpp>
+
 #include "curses/window.h"
 #include "mpdpp.h"
 #include "mutable_song.h"
@@ -36,6 +38,8 @@ MPD::MutableSong::SetFunction tagTypeToSetFunction(mpd_tag_type tag);
 mpd_tag_type charToTagType(char c);
 MPD::Song::GetFunction charToGetFunction(char c);
 
+boost::optional<mpd_tag_type> getFunctionToTagType(MPD::Song::GetFunction f);
+
 std::string itemTypeToString(MPD::Item::Type type);
 
 #endif // NCMPCPP_UTILITY_TYPE_CONVERSIONS_H