common.nim

import parasound/dr_wav
import parasound/miniaudio
import os

proc play*(data: string | seq[uint8], sleepMsecs: int): bool =
  ## if `data` is a string, it is interpreted as a filename.
  ## if `data` is a byte sequence, it is interpreted as an in-memory buffer.
  var engine = newSeq[uint8](ma_engine_size())
  if MA_SUCCESS != ma_engine_init(nil, engine[0].addr):
    return false
  when data is string:
    if MA_SUCCESS != ma_engine_play_sound(engine[0].addr, data, nil):
      ma_engine_uninit(engine[0].addr)
      return false
    os.sleep(sleepMsecs)
    ma_engine_uninit(engine[0].addr)
  elif data is seq[uint8]:
    var decoder = newSeq[uint8](ma_decoder_size())
    if MA_SUCCESS != ma_decoder_init_memory(data[0].unsafeAddr, data.len.csize_t, nil, decoder[0].addr):
      ma_engine_uninit(engine[0].addr)
      return false
    var sound = newSeq[uint8](ma_sound_size())
    if MA_SUCCESS != ma_sound_init_from_data_source(engine[0].addr, decoder[0].addr, 0, nil, sound[0].addr):
      discard ma_decoder_uninit(decoder[0].addr)
      ma_engine_uninit(engine[0].addr)
      return false
    if MA_SUCCESS != ma_sound_start(sound[0].addr):
      ma_sound_uninit(sound[0].addr)
      discard ma_decoder_uninit(decoder[0].addr)
      ma_engine_uninit(engine[0].addr)
      return false
    os.sleep(sleepMsecs)
    ma_sound_uninit(sound[0].addr)
    discard ma_decoder_uninit(decoder[0].addr)
    ma_engine_uninit(engine[0].addr)
  true

proc writeFile*(filename: string, data: var openArray[cshort], numSamples: uint32, sampleRate: uint32) =
  var
    wav = newSeq[uint8](drwav_size())
    format: drwav_data_format
  format.container = drwav_container_riff
  format.format = DR_WAVE_FORMAT_PCM
  format.channels = 1
  format.sampleRate = sampleRate
  format.bitsPerSample = 16
  doAssert drwav_init_file_write(wav[0].addr, filename, addr(format), nil)
  doAssert numSamples == drwav_write_pcm_frames(wav[0].addr, numSamples, data.addr)
  discard drwav_uninit(wav[0].addr)

proc writeMemory*(data: var openArray[cshort], numSamples: uint32, sampleRate: uint32): seq[uint8] =
  var
    wav = newSeq[uint8](drwav_size())
    format: drwav_data_format
  format.container = drwav_container_riff
  format.format = DR_WAVE_FORMAT_PCM
  format.channels = 1
  format.sampleRate = sampleRate
  format.bitsPerSample = 16
  var
    outputRaw: pointer
    outputSize: csize_t
  doAssert drwav_init_memory_write_sequential(wav[0].addr, outputRaw.addr, outputSize.addr, format.addr, numSamples, nil)
  doAssert numSamples == drwav_write_pcm_frames(wav[0].addr, numSamples, data[0].addr)
  doAssert outputSize > 0
  result = newSeq[uint8](outputSize)
  copyMem(result[0].addr, outputRaw, outputSize)
  drwav_free(outputRaw, nil)
  discard drwav_uninit(wav[0].addr)