/*
 * audriver-oss.c
 *
 * OSS sound system interface code
 *
 * Copyright (c) 2005 Todd MacDermid <tmacd@synacklabs.net>
 *                    Jack Lloyd <lloyd@randombit.net>
 */

#include <cutlass.h>

#ifdef HAVE_SYS_SOUNDCARD

#include <sys/types.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/soundcard.h>
#include <sys/stat.h>

/* FIXME: this should not be hardcoded, that's just terrible */
#define DEVICE_NAME "/dev/dsp"

extern int errno;

void *
oss_audio_open(cutlass_t *cut_handle, int rate)
{
  cutlass_oss_t *oss_handle;
  int channels = 1;

  if((NULL == cut_handle)) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: Passed a NULL pointer\n");
    return(NULL);
  }

  oss_handle = calloc(1, sizeof(cutlass_oss_t));
  if (NULL == oss_handle) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: Memory allocation failed\n");
    return(NULL);
  }
  
  oss_handle->fd = open(DEVICE_NAME, O_RDWR, 0);
  if(oss_handle->fd < 0) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: "
                   "Failed to open %s: %s\n", DEVICE_NAME, strerror(errno));
    goto fail;
  }

  oss_handle->format = AFMT_S16_NE;
  if(ioctl(oss_handle->fd, SNDCTL_DSP_SETFMT, &(oss_handle->format)) < 0) {
    oss_handle->format = AFMT_U8;
    if(ioctl(oss_handle->fd, SNDCTL_DSP_SETFMT, &(oss_handle->format)) < 0) {
      cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: "
                   "Failed to set format: %s\n", strerror(errno));
      goto fail;
    }
  }

  if(ioctl(oss_handle->fd, SNDCTL_DSP_CHANNELS, &channels) < 0) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: "
                   "Failed to set channels: %s\n", strerror(errno));
    goto fail;
  }

  if(channels != 1) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: "
                   "Could not set mono mode, and we don't support stereo "
                   "(yet)\n");
    goto fail;
  }

  oss_handle->rate = rate;
  if(ioctl(oss_handle->fd, SNDCTL_DSP_SPEED, &(oss_handle->rate)) < 0) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_open: "
                   "Failed to set rate: %s\n", strerror(errno));
    goto fail;
  }
  
  return(oss_handle);
  fail:
  free(oss_handle);
  return(NULL);
}

int
oss_audio_capture(cutlass_t *cut_handle, cutlass_oss_t *oss_handle, 
                  float *samples, int max_samples)
{
  int16_t local_samples16[CUTLASS_AUDIO_RING_SIZE];
  uint8_t local_samples8[CUTLASS_AUDIO_RING_SIZE];
  int i;
  int len;
  int to_read;

  if((NULL == cut_handle) || (NULL == oss_handle) || (NULL == samples)) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_capture: Passed a NULL pointer\n");
    return(-1);
  }
  
  if(max_samples > CUTLASS_AUDIO_RING_SIZE) {
    to_read = CUTLASS_AUDIO_RING_SIZE;
  } else {
    to_read = max_samples;
  }

  switch(oss_handle->format) {
  case AFMT_S16_NE:
    len = read(oss_handle->fd, local_samples16, to_read * 2);
    len = len/2;
    for(i = 0; (i < len) && (i < max_samples); i++) {
      samples[i] = local_samples16[i];
      /*      if(!(i%32)) {
        printf("cap %d: %f %d\n", i, samples[i], local_samples16[i]);
        } */
    }
    break;
  case AFMT_U8:
    len = read(oss_handle->fd, local_samples8, to_read);
    for(i = 0; (i < len) && (i < max_samples); i++) {
      samples[i] = (local_samples8[i] - 128) * 256.0;
    }
    break;
  default:
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_capture: oss_handle has unknown format\n");
    return(-1);
  }
  
  if(len < 0) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_capture: Read returned %d bytes: %s\n",
                   len, strerror(errno));
  }
  
  return(len);
}

int
oss_audio_play(cutlass_t *cut_handle, cutlass_oss_t *oss_handle, 
               float *samples, int num_samples)
{
  int16_t local_samples16[CUTLASS_AUDIO_RING_SIZE];
  uint8_t local_samples8[CUTLASS_AUDIO_RING_SIZE];
  int i;
  int len;
  int num_bytes;

  if((NULL == cut_handle) || (NULL == oss_handle) || (NULL == samples)) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_play: Passed a NULL pointer\n");
    return(-1);
  }
  
  switch(oss_handle->format) {
  case AFMT_S16_NE:
    for(i = 0; (i < num_samples) && (i < CUTLASS_AUDIO_RING_SIZE); i++) {
      local_samples16[i] = samples[i];
    }
    num_bytes = num_samples * 2;
    len = write(oss_handle->fd, local_samples16, num_bytes);
    break;
  case AFMT_U8:
    for(i = 0; (i < num_samples) && (i < CUTLASS_AUDIO_RING_SIZE); i++) {
      local_samples8[i] = ((samples[i] / 256) + 128);
    }
    num_bytes = num_samples;
    len = write(oss_handle->fd, local_samples8, num_bytes);
    break;
  default:
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_play: oss_handle has unknown format\n");
    return(-1);
  }
  
  if(len != num_bytes) {
    cutlass_sysmsg(cut_handle, CUT_ERROR,
                   "oss_audio_play: Meant to write %d samples, wrote %d\n",
                   num_samples, len);
    return(-1);
  }

  return(0);
}

int
oss_audio_close(cutlass_oss_t *oss_handle)
{
  
  close(oss_handle->fd);
  free(oss_handle);
  return(0);
}

#else /* no sys/soundcard.h */

#include <cutlass.h>

void *
oss_audio_open(cutlass_t *cut_handle, int rate)
{
    return NULL;
}

int
oss_audio_close(cutlass_oss_t *oss_handle)
{
    return 0;
}

int
oss_audio_capture(cutlass_t *cut_handle, cutlass_oss_t *oss_handle, 
                  float *samples, int max_samples)
{
    return -1;
}

int
oss_audio_play(cutlass_t *cut_handle, cutlass_oss_t *oss_handle, 
               float *samples, int num_samples)
{
    return -1;
}

#endif