pub suberror TagError {
  Truncated(offset~ : Int, need~ : Int, actual~ : Int)
  NotTagged(format~ : String)
  BadHeader(reason~ : String)
  BadFrameHeader(reason~ : String)
  FrameOutOfBounds(frame_id~ : String, size~ : Int, available~ : Int)
  BadFrameData(frame_id~ : String, reason~ : String)
  Unsupported(what~ : String)
  UnsupportedVersion(version~ : Int)
}

pub struct ApeItem {
  key : String
  is_binary : Bool
  value : Bytes
}

pub struct ApeTag {
  items : Array[ApeItem]
  size : Int
  offset : Int
}

pub enum AudioFormat {
  Mp3
  Flac
  Mp4
  Ogg
  Unknown
}

pub struct ExistingTag {
  tag : Id3Tag?
  size : Int
}

pub struct FlacBlock {
  code : Int
  offset : Int
  length : Int
  is_last : Bool
}

pub enum FlacBlockType {
  StreamInfo
  Padding
  Application
  SeekTable
  VorbisComment
  CueSheet
  Picture
  Reserved
  Invalid
}

pub struct FlacMeta {
  blocks : Array[FlacBlock]
  audio_offset : Int
}

pub struct Frame {
  id : String
  data : Bytes
  status_flags : Int
  format_flags : Int
  group : Int?
}

pub struct Id3Tag {
  major : Int
  revision : Int
  flags : Int
  frames : Array[Frame]
  total_size : Int
}

pub struct Mp4Box {
  kind : String
  offset : Int
  length : Int
  start : Int
}

pub struct Mp4Tag {
  key : String
  value : Bytes
  data_type : Int
}

pub struct OggCommentLoc {
  payload : Bytes
  end_offset : Int
  serial : Int
  is_opus : Bool
}

pub struct OggPage {
  offset : Int
  n_segments : Int
  total_len : Int
  body_offset : Int
  is_bos : Bool
  is_eos : Bool
  is_continued : Bool
  serial : Int
  seq : Int
  data : Bytes
}

pub struct Picture {
  mime : String
  picture_type : PictureType
  raw_type : Int
  description : String
  data : Bytes
}

pub(all) enum PictureType {
  Other
  FileIcon
  OtherIcon
  FrontCover
  BackCover
  LeafletPage
  Media
  LeadArtist
  Artist
  Conductor
  Band
  Composer
  Lyricist
  RecordingLocation
  DuringRecording
  DuringPerformance
  MovieScreenCapture
  BrightColouredFish
  Illustration
  BandLogotype
  PublisherLogotype
}

pub struct TagField {
  id : String
  value : String
}

pub enum TextEncoding {
  Latin1
  Utf16Bom
  Utf16Be
  Utf8
}

pub struct TrackInfo {
  format : AudioFormat
  title : String?
  artist : String?
  album : String?
  track : String?
  date : String?
  genre : String?
  comment : String?
  has_cover : Bool
}

pub struct VorbisComment {
  vendor : String
  entries : Array[String]
}

pub struct WriteOptions {
  padding : Int
  default_major : Int
}

let OGG_HEADER_SIZE : Int

fn assemble_packets(data : Bytes, pages : Array[OggPage]) -> Array[Bytes]

fn cover_of(entries : Array[Mp4Tag]) -> Bytes?

fn detect_format(data : BytesView) -> AudioFormat

fn empty_ape_tag() -> ApeTag

fn empty_vorbis_comment(vendor : String) -> VorbisComment

fn field(id : String, value : String) -> TagField

fn find_ilst(data : BytesView) -> Mp4Box? raise TagError

fn make_page(serial : Int, seq : Int, header_type : Int, granule : Int64, payload : Bytes) -> Bytes

fn make_page_multi(serial : Int, seq : Int, header_type : Int, granule : Int64, packets : Array[Bytes]) -> Bytes

fn mp4_cover_tag(image : Bytes, is_png : Bool) -> Mp4Tag

fn mp4_text_tag(key : String, value : String) -> Mp4Tag

fn ogg_crc32(data : Bytes) -> UInt

fn parse(data : BytesView) -> Id3Tag raise TagError

fn parse_ape(data : BytesView) -> ApeTag? raise TagError

fn parse_ilst(data : BytesView, ilst : Mp4Box) -> Array[Mp4Tag] raise TagError

fn parse_meta(data : BytesView) -> FlacMeta raise TagError

fn parse_ogg_comment_payload(loc : OggCommentLoc) -> VorbisComment raise TagError

fn parse_page(data : Bytes, offset : Int) -> OggPage raise TagError

fn parse_picture(payload : BytesView) -> Picture raise TagError

fn parse_vorbis_comment(payload : BytesView) -> VorbisComment raise TagError

fn picture(mime : String, picture_type : PictureType, description : String, data : Bytes) -> Picture

fn read_mp4_tags(data : BytesView) -> Array[Mp4Tag] raise TagError

fn read_ogg_comment(data : Bytes) -> OggCommentLoc?

fn read_track_info(data : BytesView) -> TrackInfo raise TagError

fn read_vorbis_comment(data : BytesView) -> VorbisComment? raise TagError

fn serialize_picture(pic : Picture, major : Int) -> Bytes raise TagError

fn serialize_vorbis_comment(vc : VorbisComment) -> Bytes

fn set_ape_tag(data : BytesView, tag : ApeTag) -> Bytes raise TagError

fn set_fields(data : BytesView, fields : Array[TagField], options : WriteOptions) -> Bytes raise TagError

fn set_mp4_tags(data : BytesView, updates : Array[Mp4Tag]) -> Bytes raise TagError

fn set_ogg_comment(data : Bytes, vc : VorbisComment) -> Bytes raise TagError

fn set_picture(data : BytesView, picture : Picture?, options : WriteOptions) -> Bytes raise TagError

fn set_vorbis_comment(data : BytesView, vc : VorbisComment) -> Bytes raise TagError

fn split_strings(data : BytesView, encoding : TextEncoding, start : Int, end : Int) -> Array[String]

fn text_of(entries : Array[Mp4Tag], key : String) -> String?

fn unsynchronise(data : BytesView) -> Bytes