var tween  = use('prosperon/tween')
var io     = use('cellfs')
var res    = use('resources')
var doc    = use('doc')
var wav = use('audio/wav')
var mp3 = use('audio/mp3')
var flac = use('audio/flac')
var dsp = use('audio/dsp')

var audio = {}
var pcms  = {}

// keep every live voice here so GC can’t collect it prematurely
var voices = []

// load-and-cache WAVs/MP3s/FLACs
audio.pcm = function pcm(file) {
  file = res.find_sound(file); if (!file) return
  if (pcms[file]) return pcms[file]
  
  var buf = io.slurp(file)
  if (!buf) return null

  var decoded = null
  if (file.endsWith('.wav')) {
    decoded = wav.decode(buf)
  } else if (file.endsWith('.mp3')) {
    decoded = mp3.decode(buf)
  } else if (file.endsWith('.flac')) {
    decoded = flac.decode(buf)
  }

  if (decoded && decoded.pcm) {
    // Store extra info needed for playback
    decoded.file = file
    return pcms[file] = decoded
  }
  return null
}

function cleanup() {
  // Remove voices that have finished playing
  var active_voices = []
  for (var i = 0; i < voices.length; i++) {
    var v = voices[i]
    // Check if voice has finished (pos >= total_frames)
    // We can calculate total frames from pcm length and format
    var total_samples = v.pcm.length / 4 // f32 is 4 bytes
    var total_frames = total_samples / v.channels
    
    if (v.pos < total_frames && !v.stopped) {
      active_voices.push(v)
    } else {
        v.finish_hook?.()
    }
  }
  voices = active_voices
}

// Voice class
function Voice(pcm_data) {
    this.pcm = pcm_data.pcm
    this.channels = pcm_data.channels || 1
    this.sample_rate = pcm_data.sample_rate || 44100
    this.pos = 0
    this.vol = 1.0
    this.stopped = false
}

Voice.prototype.stop = function() {
    this.stopped = true
}

Voice.prototype.set_volume = function(v) {
    this.vol = v
}

// play a one‑shot; returns the voice for volume/stop control
audio.play = function play(file) {
  var pcm_data = audio.pcm(file); if (!pcm_data) return
  var voice = new Voice(pcm_data)
  voices.push(voice)
  return voice
}

// cry is just a play+stop closure
audio.cry = function cry(file) {
  var v = audio.play(file); if (!v) return
  return function() { v.stop(); v = null }
}

//
// pump + periodic cleanup
//
var ss      = use('sdl/audio')
var feeder  = ss.open_stream("playback")
// We output stereo float32 at 44100Hz
feeder.set_format({format:"f32", channels:2, samplerate:44100})
feeder.resume()

var FRAMES       = 1024
var CHANNELS     = 2
var BYTES_PER_F  = 4
var CHUNK_BYTES  = FRAMES * CHANNELS * BYTES_PER_F

function pump() {
  // Keep buffer full
  if (feeder.queued() < CHUNK_BYTES*3) {
    // Mix voices
    var mixed_blob = dsp.mix(voices, FRAMES)
    if (mixed_blob) {
        feeder.put(mixed_blob)
    } else {
        // If mix failed or no voices, output silence? 
        // dsp.mix should return silence if no voices, but let's be safe
        // Actually dsp.mix returns a zeroed buffer if no voices.
    }
    cleanup()
  }
  $_.delay(pump, 1/240)
}

pump()

return audio