ybot_audio_file_player.xtm

;; Include guard
(if (and (defined? '*xtmlib-ybot-audio-file-player-loaded*) *xtmlib-ybot-audio-file-player-loaded*)
    (sys:load-escape "ybot_audio_file_player library already loaded"))
(define *xtmlib-ybot-audio-file-player-loaded* #f)

(if (not (defined? '*ybot-lib-dir*))
    (sys:load-escape "Set the *ybot-lib-dir* variable before loading this library"))
(sys:load (string-append *ybot-lib-dir* "/ybot_audio_file_reader.xtm"))
(sys:load (string-append *ybot-lib-dir* "/samplerate.xtm"))

;; Other Dependencies
;; returns the audio SAMPLE, inputs are desired frame, desired channel, and desired samplerate
(bind-alias YbotAudioFilePlayer_t [SAMPLE,i64,i64,SAMPLE]*)
(bind-val YAFP_READBUF_WIDTH i64 10000000)
(bind-val YAFP_SRCBUF_SIZE i64 FRAMES)

(bind-func YbotAudioFilePlayer_c:[YbotAudioFilePlayer_t,i8*]*
  (lambda (filename)
    (let 
        ((play_sr:SAMPLE SAMPLERATE)
         (reader:YbotAudioFileReader_t (YbotAudioFileReader_c filename 1000000))
         (pError:i32* (zalloc))
         (inputSampleRate:SAMPLE (reader.samplerate:SAMPLE))
         (inputFrames:i64 (reader.frames:i64))
         (inputChannels:i64 (reader.channels:i64))
         (inputBuffer:float* (zalloc YAFP_SRCBUF_SIZE))
         (converter_src_callback:src_callback_t
          (lambda (pUserData:i8* pBuffer:float**)
            (let* ((pTransport:i64* (cast pUserData i64*))
                   (inputFrame:i64 (pref pTransport 0))
                   (inputChannel:i64 (pref pTransport 1))
                   (cc:i64 0))
              (dotimes (cc (* inputFrames inputChannels))
                (pset! inputBuffer cc (reader inputFrame inputChannel)))
              (pset! pBuffer 0 inputBuffer)
              (* inputFrames inputChannels))))
         (src:SRC_STATE* (src_callback_new converter_src_callback SRC_SINC_BEST_QUALITY (i64toi32 inputChannels) pError null)))
      (lambda (frame:i64 channel:i64 rate:SAMPLE)
        (let ((pOutput:SAMPLE* (zalloc 1)))
          (src_callback_read src (/ (ftod rate) (ftod inputSampleRate)) 1 pOutput)
          (pref pOutput channel))))))



;;;;; Example usage ;;;;;;
(bind-func dsp:DSP
 (let* ((playhead:i64 0)
        (playing:i64 1)
        (master_gain:float 0.2)
        (player (YbotAudioFilePlayer_c "/Users/s2805534/Dropbox/ybot/grants/SwishGoTheFish/audio/Crossbows/Toby_CrossbowsMixStereo.wav"))
        (val:float 0.0))
   (lambda (in:SAMPLE time:i64 channel:i64	data:SAMPLE*)
     (if (< 0 playing)
         (set! val (player playhead channel SAMPLERATE))
         (set! val (dtof 0.0)))
     (cond ((= channel 0)
            (set! playhead (+ playhead 1))
            (cond ((> playhead (player.reader.frames:i64))
                   (println "Looping")
                   (set! playhead 0)))))
     (* master_gain val))))


(dsp:set! dsp)
(dsp.master_gain 0.5)
;; (dsp.playhead 0)
(dsp.playing 1)