/**
  audio: this file implements the audio system.
*/

#ifndef _LCR_AUDIO
#define _LCR_AUDIO

#define LCR_SOUND_NONE 0
#define LCR_SOUND_CLICK 1
#define LCR_SOUND_CRASH 2
#define LCR_SOUND_ACCELERATOR 3

#define LCR_AUDIO_MIN_RPM 128
#define LCR_AUDIO_MAX_RPM 2048

struct
{
  uint32_t frame;
  uint8_t soundPlayed;
  uint16_t soundPlayedSample;
  uint32_t noise;


int engineIntensity;
int engineOsc;




} LCR_audio;

void LCR_audioInit(void)
{
  LCR_LOG0("initializing audio");
  LCR_audio.frame = 0;
  LCR_audio.soundPlayed = LCR_SOUND_NONE;
  LCR_audio.soundPlayedSample = 0;
  LCR_audio.noise = 0;

LCR_audio.engineOsc = 0;
LCR_audio.engineIntensity = 0;

}

void LCR_audioSetEngineIntensity(uint8_t value)
{
  LCR_audio.engineIntensity = value;
}

void LCR_audioPlaySound(uint8_t sound)
{
  LCR_audio.soundPlayed = sound;
  LCR_audio.soundPlayedSample = 0;
}

uint8_t _LCR_audioNoise(void)
{
  LCR_audio.noise = LCR_audio.noise * 32310901 + 37;
  return LCR_audio.noise >> 16;
}

uint8_t LCR_audioGetNextSample(void)
{
  unsigned char result = 128;

  if (LCR_audio.engineIntensity > 5)
  {
    LCR_audio.engineOsc += 
      ((_LCR_audioNoise() % 256) < 
        (30 + LCR_audio.engineIntensity));

    result += LCR_audio.engineOsc;
  }

  LCR_audio.frame++;

  return result;
}



#endif // guard