#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/shm.h>
#include <sys/wait.h>
#include <linux/soundcard.h>
#include <stdio.h>
#include "quakedef.h"

int audio_fd;
int snd_inited;

static int tryrates[] = { 11025, 22051, 44100, 8000 };

qboolean SNDDMA_Init(void)
{

  int rc;
    int fmt;
  int tmp;
    int i;
    char *s;
  struct audio_buf_info info;
  int caps;

  snd_inited = 0;

// open /dev/dsp, confirm capability to mmap, and get size of dma buffer

    audio_fd = open("/dev/dsp", O_RDWR);
    if (audio_fd < 0)
  {
    perror("/dev/dsp");
        Con_Printf("Could not open /dev/dsp\n");
    return 0;
  }

    rc = ioctl(audio_fd, SNDCTL_DSP_RESET, 0);
    if (rc < 0)
  {
    perror("/dev/dsp");
    Con_Printf("Could not reset /dev/dsp\n");
    close(audio_fd);
    return 0;
  }

  if (ioctl(audio_fd, SNDCTL_DSP_GETCAPS, &caps)==-1)
  {
    perror("/dev/dsp");
        Con_Printf("Sound driver too old\n");
    close(audio_fd);
    return 0;
  }

  if (!(caps & DSP_CAP_TRIGGER) || !(caps & DSP_CAP_MMAP))
  {
    Con_Printf("Sorry but your soundcard can't do this\n");
    close(audio_fd);
    return 0;
  }

    if (ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &info)==-1)
    {   
        perror("GETOSPACE");
    Con_Printf("Um, can't do GETOSPACE?\n");
    close(audio_fd);
    return 0;
    }
    
  shm = &sn;
    shm->splitbuffer = 0;

// set sample bits & speed

    s = getenv("QUAKE_SOUND_SAMPLEBITS");
    if (s) shm->samplebits = atoi(s);
  else if ((i = COM_CheckParm("-sndbits")) != 0)
    shm->samplebits = atoi(com_argv[i+1]);
  if (shm->samplebits != 16 && shm->samplebits != 8)
    {
        ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &fmt);
        if (fmt & AFMT_S16_LE) shm->samplebits = 16;
        else if (fmt & AFMT_U8) shm->samplebits = 8;
    }

    s = getenv("QUAKE_SOUND_SPEED");
    if (s) shm->speed = atoi(s);
  else if ((i = COM_CheckParm("-sndspeed")) != 0)
    shm->speed = atoi(com_argv[i+1]);
    else
    {
        for (i=0 ; i<sizeof(tryrates)/4 ; i++)
            if (!ioctl(audio_fd, SNDCTL_DSP_SPEED, &tryrates[i])) break;
        shm->speed = tryrates[i];
    }

    s = getenv("QUAKE_SOUND_CHANNELS");
    if (s) shm->channels = atoi(s);
  else if ((i = COM_CheckParm("-sndmono")) != 0)
    shm->channels = 1;
  else if ((i = COM_CheckParm("-sndstereo")) != 0)
    shm->channels = 2;
    else shm->channels = 2;

  shm->samples = info.fragstotal * info.fragsize / (shm->samplebits/8);
  shm->submission_chunk = 1;

// memory map the dma buffer

  shm->buffer = (unsigned char *) mmap(NULL, info.fragstotal
    * info.fragsize, PROT_WRITE, MAP_FILE|MAP_SHARED, audio_fd, 0);
  if (!shm->buffer)
  {
    perror("/dev/dsp");
    Con_Printf("Could not mmap /dev/dsp\n");
    close(audio_fd);
    return 0;
  }

  tmp = 0;
  if (shm->channels == 2)
    tmp = 1;
    rc = ioctl(audio_fd, SNDCTL_DSP_STEREO, &tmp);
    if (rc < 0)
    {
    perror("/dev/dsp");
        Con_Printf("Could not set /dev/dsp to stereo=%d", shm->channels);
    close(audio_fd);
        return 0;
    }
  if (tmp)
    shm->channels = 2;
  else
    shm->channels = 1;

    rc = ioctl(audio_fd, SNDCTL_DSP_SPEED, &shm->speed);
    if (rc < 0)
    {
    perror("/dev/dsp");
        Con_Printf("Could not set /dev/dsp speed to %d", shm->speed);
    close(audio_fd);
        return 0;
    }

    if (shm->samplebits == 16)
    {
        rc = AFMT_S16_LE;
        rc = ioctl(audio_fd, SNDCTL_DSP_SETFMT, &rc);
        if (rc < 0)
    {
      perror("/dev/dsp");
      Con_Printf("Could not support 16-bit data.  Try 8-bit.\n");
      close(audio_fd);
      return 0;
    }
    }
    else if (shm->samplebits == 8)
    {
        rc = AFMT_U8;
        rc = ioctl(audio_fd, SNDCTL_DSP_SETFMT, &rc);
        if (rc < 0)
    {
      perror("/dev/dsp");
      Con_Printf("Could not support 8-bit data.\n");
      close(audio_fd);
      return 0;
    }
    }
  else
  {
    perror("/dev/dsp");
    Con_Printf("%d-bit sound not supported.", shm->samplebits);
    close(audio_fd);
    return 0;
  }

// toggle the trigger & start her up

    tmp = 0;
    rc  = ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &tmp);
  if (rc < 0)
  {
    perror("/dev/dsp");
    Con_Printf("Could not toggle.\n");
    close(audio_fd);
    return 0;
  }
    tmp = PCM_ENABLE_OUTPUT;
    rc = ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &tmp);
  if (rc < 0)
  {
    perror("/dev/dsp");
    Con_Printf("Could not toggle.\n");
    close(audio_fd);
    return 0;
  }

  shm->samplepos = 0;

  snd_inited = 1;
  return 1;

}

int SNDDMA_GetDMAPos(void)
{

  struct count_info count;

  if (!snd_inited) return 0;

  if (ioctl(audio_fd, SNDCTL_DSP_GETOPTR, &count)==-1)
  {
    perror("/dev/dsp");
    Con_Printf("Uh, sound dead.\n");
    close(audio_fd);
    snd_inited = 0;
    return 0;
  }
//  shm->samplepos = (count.bytes / (shm->samplebits / 8)) & (shm->samples-1);
//  fprintf(stderr, "%d    \r", count.ptr);
  shm->samplepos = count.ptr / (shm->samplebits / 8);

  return shm->samplepos;

}

void SNDDMA_Shutdown(void)
{
  if (snd_inited)
  {
    close(audio_fd);
    snd_inited = 0;
  }
}

/*
==============
SNDDMA_Submit

Send sound to device if buffer isn't really the dma buffer
===============
*/
void SNDDMA_Submit(void)
{
}