package model import ( "errors" "fmt" "strings" ) type Kind struct { prefix string name string } func (k Kind) String() string { return k.name } var ( KindMediaFileArtwork = Kind{"mf", "media_file"} KindArtistArtwork = Kind{"ar", "artist"} KindAlbumArtwork = Kind{"al", "album"} KindPlaylistArtwork = Kind{"pl", "playlist"} ) var artworkKindMap = map[string]Kind{ KindMediaFileArtwork.prefix: KindMediaFileArtwork, KindArtistArtwork.prefix: KindArtistArtwork, KindAlbumArtwork.prefix: KindAlbumArtwork, KindPlaylistArtwork.prefix: KindPlaylistArtwork, } type ArtworkID struct { Kind Kind ID string } func (id ArtworkID) String() string { if id.ID == "" { return "" } return fmt.Sprintf("%s-%s", id.Kind.prefix, id.ID) } func NewArtworkID(kind Kind, id string) ArtworkID { return ArtworkID{kind, id} } func ParseArtworkID(id string) (ArtworkID, error) { parts := strings.SplitN(id, "-", 2) if len(parts) != 2 { return ArtworkID{}, errors.New("invalid artwork id") } if kind, ok := artworkKindMap[parts[0]]; !ok { return ArtworkID{}, errors.New("invalid artwork kind") } else { return ArtworkID{ Kind: kind, ID: parts[1], }, nil } } func MustParseArtworkID(id string) ArtworkID { artID, err := ParseArtworkID(id) if err != nil { panic(artID) } return artID } func artworkIDFromAlbum(al Album) ArtworkID { return ArtworkID{ Kind: KindAlbumArtwork, ID: al.ID, } } func artworkIDFromMediaFile(mf MediaFile) ArtworkID { return ArtworkID{ Kind: KindMediaFileArtwork, ID: mf.ID, } } func artworkIDFromPlaylist(pls Playlist) ArtworkID { return ArtworkID{ Kind: KindPlaylistArtwork, ID: pls.ID, } } func artworkIDFromArtist(ar Artist) ArtworkID { return ArtworkID{ Kind: KindArtistArtwork, ID: ar.ID, } }