#ifdef WITHSOUND

#include "snd.h"

ALCdevice *adev;

ALCcontext *actx;

void sndInit() {

  if (adev) return;

  adev = alcOpenDevice(NULL);

  if (!adev) LOGWRN("sndInit: cannot open device");

  actx = alcCreateContext(adev, NULL);

  if (!actx) LOGWRN("sndInit: cannot create context");

  alcMakeContextCurrent(actx);

}

void sndDeinit() {

  alcMakeContextCurrent(NULL);

  if (actx) alcDestroyContext(actx);

  if (adev) alcCloseDevice(adev);

  actx = NULL;

  adev = NULL;

}

void sndFree(Sound *snd) {

  if (!snd) return;

  if (snd->src) alDeleteSources(1, &snd->src);

  if (snd->buf) alDeleteBuffers(1, &snd->buf);

  *snd = (Sound){};

}

Sound sndGen(int rate, int freq, int samples) {

  Sound snd = {};

  if (rate <= 0 || freq <= 0 || samples <= 0)

    return snd;

  short *buf = malloc(samples*sizeof(*buf));

  if (!buf)

    return LOGERR("sndGen: cannot alocate memory for samples (%d)", samples), (Sound){};

  for(int i = 0; i < samples; ++i)

    buf[i] = (int)(32760*sin(2*3.14159*i*freq/rate));

  alGenBuffers(1, &snd.buf);

  alBufferData(snd.buf, AL_FORMAT_MONO16, buf, sizeof(*buf)*samples, rate);

  free(buf);

  alGenSources(1, &snd.src);

  alSourcei(snd.src, AL_BUFFER, snd.buf);

  return snd;

}

Sound sndLoadRaw(const char *filename, int rate) {

  LOGDBG("sndLoadRaw: open: %s", filename);

  FILE *f = fopen(filename, "rb");

  if (!f)

    return LOGERR("sndLoadRaw: cannot open file for read: %s", filename), (Sound){};

  fseek(f, 0, SEEK_END);

  int samples = ftell(f)/sizeof(short);

  fseek(f, 0, SEEK_SET);

  if (samples <= 0)

    return LOGERR("sndLoadRaw: file is empty: %s", filename), (Sound){};

  unsigned short *buf = (unsigned short*)malloc(sizeof(*buf)*samples);

  if (!buf)

    return LOGERR("sndGen: cannot alocate memory for samples (%d): %s", samples, filename), fclose(f), (Sound){};

  for(int i = 0; i < samples; ++i) {

    unsigned int a = fgetc(f), b = fgetc(f);

    buf[i] = a | (b << 8);

  }

  fclose(f);

  Sound snd = {};

  alGenBuffers(1, &snd.buf);

  alBufferData(snd.buf, AL_FORMAT_MONO16, buf, sizeof(*buf)*samples, rate);

  free(buf);

  alGenSources(1, &snd.src);

  alSourcei(snd.src, AL_BUFFER, snd.buf);

  return snd;

}

void sndPlay(Sound snd) {

  LOGDBG("sndPlay: %d", snd.src);

  alSourcePlay(snd.src);

}

#endif