module Synthesizer.Storable.ALSA.Server.Common where

import qualified Sound.ALSA.PCM as ALSA
import qualified Sound.ALSA.Sequencer.Event as Event
import qualified Synthesizer.Storable.ALSA.Play as Play

import qualified Synthesizer.EventList.ALSA.MIDI as MIDIEv
import Synthesizer.EventList.ALSA.MIDI (Channel, StrictTime, )

import qualified Synthesizer.Storable.Signal      as SigSt
import qualified Data.StorableVector.Lazy         as SVL

import qualified Synthesizer.Generic.Signal    as SigG

import qualified Sound.MIDI.Message.Channel       as ChannelMsg

import qualified Data.EventList.Relative.TimeBody  as EventList

import qualified Sound.Sox.Frame         as SoxFrame

import Control.Category ((.), )

import qualified Algebra.RealField as RealField
import qualified Algebra.Field     as Field
import qualified Algebra.Ring      as Ring
import qualified Algebra.ToInteger as ToInteger
import qualified Algebra.Additive  as Additive

import NumericPrelude.Numeric (zero, round, )
import Prelude hiding (Real, round, break, id, (.), )


channel :: Channel
channel = ChannelMsg.toChannel 0

sampleRate :: Num a => a
-- sampleRate = 24000
-- sampleRate = 48000
sampleRate = 44100

latency :: Int
latency = 0
-- latency = 256
-- latency = 1000

chunkSize :: SVL.ChunkSize
chunkSize = Play.defaultChunkSize

lazySize :: SigG.LazySize
lazySize =
   let (SVL.ChunkSize size) = chunkSize
   in  SigG.LazySize size

periodTime :: Field.C t => t
periodTime =
   let (SVL.ChunkSize size) = chunkSize
   in  ToInteger.fromIntegral size Field./ Ring.fromInteger sampleRate


type Real = Float


{-# INLINE withMIDIEvents #-}
withMIDIEvents ::
   (Double -> Double -> a -> IO b) ->
   (EventList.T StrictTime [Event.T] -> a) -> IO b
withMIDIEvents action proc =
   let rate = sampleRate
       per  = periodTime
   in  MIDIEv.withMIDIEvents per rate $
       action per rate . proc


{-# INLINE play #-}
play ::
   (RealField.C t, Additive.C y, ALSA.SampleFmt y) =>
   t -> t -> SigSt.T y -> IO ()
play period rate =
   Play.auto period (round rate) .
   SigSt.append (SigSt.replicate chunkSize latency zero)
--   FiltG.delayPosLazySize chunkSize latency
--   FiltG.delayPos latency

-- ToDo: do not record the empty chunk that is inserted for latency
{-# INLINE playAndRecord #-}
playAndRecord ::
   (RealField.C t, Additive.C y, ALSA.SampleFmt y, SoxFrame.C y) =>
   FilePath -> t -> t -> SigSt.T y -> IO ()
playAndRecord fileName period rate =
   Play.autoAndRecord period fileName (round rate) .
   SigSt.append (SigSt.replicate chunkSize latency zero)