module Melody
    exposing
        ( NoteEvent(..)
        , MelodyLine
        , SingleNote
        , ABar
        )

{-| Data structures for describing an ABC melody  (i.e just a succession of notes and durations)

# Definition

# Data Types
@docs NoteEvent, MelodyLine, SingleNote, ABar

-}

import Abc.ParseTree exposing (PitchClass, Accidental, KeySet, Repeat)
import Music.Notation exposing (NoteTime, MidiPitch)
import Music.Accidentals exposing (Accidentals)
import RepeatTypes exposing (GeneralisedBar)


{-| an individual Note (no pitch class implies a rest)
-}
type alias SingleNote =
    { time : NoteTime
    , pitch : MidiPitch
    , pc : Maybe PitchClass
    , accidental : Maybe Accidental
    }


{-| a Note Event (note or chord)
-}
type NoteEvent
    = ANote SingleNote Bool
      -- Bool indicates whether note is tied
    | AChord (List SingleNote)



{- A Bar -}


type alias ABar =
    GeneralisedBar NoteEvent



{- GeneralisedBar is a parameterised type defined in RepeatTypes.elm
      which makes ABar (when expanded) look like this:
   type alias ABar =
     {  number : Int               -- sequential from zero
     ,  repeat : Maybe Repeat      -- the bar owns a repeat of some kind
     ,  iteration : Maybe Int      -- the bar has an iteration marker  (|1  or |2 etc)
     ,  accidentals : Accidentals  -- any notes marked explicitly as accidentals in the bar (updated in sequence)
     ,  notes : List NoteEvent     -- the notes in the bar
     }
-}
{- the overall melody -}


type alias MelodyLine =
    List ABar