/*
Copyright (C) 1996-1997 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/

#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"
#include "sound.h"

int audio_fd;
int snd_inited;

static char snd_dev[64] = "/dev/dsp";

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

qboolean SNDDMA_Init(void) {
	int rc, fmt, tmp, caps, i;
    char *s;
	struct audio_buf_info info;

	snd_inited = 0;

	// open snd_dev, confirm capability to mmap, and get size of dma buffer
	if ((i = COM_CheckParm("-snddev"))&& i < com_argc - 1)
		Q_strncpyz (snd_dev, com_argv[i + 1], sizeof(snd_dev));

    audio_fd = open(snd_dev, O_RDWR|O_NONBLOCK);
    if (audio_fd < 0) {
		perror(snd_dev);
        Com_Printf ("Could not open %s\n", snd_dev);
		return 0;
	}

    rc = ioctl(audio_fd, SNDCTL_DSP_RESET, 0);
    if (rc < 0) {
		perror(snd_dev);
		Com_Printf ("Could not reset %s\n", snd_dev);
		close(audio_fd);
		return 0;
	}

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

	if (!(caps & DSP_CAP_TRIGGER) || !(caps & DSP_CAP_MMAP)) {
		Com_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");
		Com_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")) && i + 1 < com_argc)
		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")) && i + 1 < com_argc) {
		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 (COM_CheckParm("-sndmono"))
		shm->channels = 1;
	else if (COM_CheckParm("-sndstereo"))
		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 = (byte *) mmap(NULL, info.fragstotal * info.fragsize, PROT_WRITE, MAP_FILE|MAP_SHARED, audio_fd, 0);
	if (!shm->buffer) {
		perror(snd_dev);
		Com_Printf ("Could not mmap %s\n", snd_dev);
		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(snd_dev);
        Com_Printf ("Could not set %s to stereo=%d", snd_dev, 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(snd_dev);
        Com_Printf ("Could not set %s speed to %d", snd_dev, 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(snd_dev);
			Com_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(snd_dev);
			Com_Printf ("Could not support 8-bit data.\n");
			close(audio_fd);
			return 0;
		}
    } else {
		perror(snd_dev);
		Com_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(snd_dev);
		Com_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(snd_dev);
		Com_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(snd_dev);
		Com_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;
	}
}

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