/*
Copyright (C) 1997-2001 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 <pthread.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 "../client/client.h"
#include "../client/snd_loc.h"

#define FRAGSIZEEXP 9
#define FRAGSIZE    (1<<FRAGSIZEEXP)

#define AUDIOBUFFERSIZE 4096
#define AUDIOBUFFERS    64

static int audio_fd = -1;
static volatile int snd_inited;
static volatile int frags_sent;
static int mmapped = 0;

cvar_t *sndbits;
cvar_t *sndspeed;
cvar_t *sndchannels;
cvar_t *snddevice;

static int tryrates[] = { 11025, 22051, 44100, 48000, 8000 };

static pthread_t audio;

void * thesound(void * arg) {
	while (snd_inited) {
		write(audio_fd, dma.buffer + frags_sent * FRAGSIZE, FRAGSIZE);
		frags_sent++;
		frags_sent &= (dma.samples * (dma.samplebits/8) / FRAGSIZE) - 1;
	}
	pthread_exit(0L);
}

qboolean SNDDMA_Init(void)
{
	int rc;
    int fmt;
	int tmp;
    int i;
	struct audio_buf_info info;
	int caps;
	extern uid_t saved_euid;

	if (snd_inited)
		return 1;

	snd_inited = 0;

	if (!snddevice)
	{
		sndbits = Cvar_Get("sndbits", "16", CVAR_ARCHIVE);
		sndspeed = Cvar_Get("sndspeed", "0", CVAR_ARCHIVE);
		sndchannels = Cvar_Get("sndchannels", "2", CVAR_ARCHIVE);
		snddevice = Cvar_Get("snddevice", "/dev/dsp", CVAR_ARCHIVE);
	}

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

	if (audio_fd == -1)
	{
		seteuid(saved_euid);

		audio_fd = open(snddevice->string, O_RDWR);

		if (audio_fd == -1)
		{
			perror(snddevice->string);
			seteuid(getuid());
			Com_Printf("SNDDMA_Init: Could not open %s.\n", snddevice->string);
			return 0;
		}
		seteuid(getuid());
	}

    rc = ioctl(audio_fd, SNDCTL_DSP_RESET, 0);
    if (rc == -1)
	{
		perror(snddevice->string);
		Com_Printf("SNDDMA_Init: Could not reset %s.\n", snddevice->string);
		close(audio_fd);
		audio_fd = -1;
		return 0;
	}

	if (ioctl(audio_fd, SNDCTL_DSP_GETCAPS, &caps) == -1
			|| !(caps & DSP_CAP_TRIGGER) || !(caps & DSP_CAP_MMAP)) {
		Com_Printf("SNDDMA_Init: Sound device does not support mmap");
	} else {
		if (ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &info) == -1) {
			perror(snddevice->string);
			Com_Printf("SNDDMA_Init: Sound driver too old.\n");
			close(audio_fd);
			audio_fd = -1;
			return 0;
		} else
			mmapped = 1;
	}

	if (!(caps & DSP_CAP_TRIGGER) || !(caps & DSP_CAP_MMAP)) {
		if (!mmapped) {
			int frags = 2 << 16 | FRAGSIZEEXP;

			if (ioctl(audio_fd, SNDCTL_DSP_SETFRAGMENT, &frags) == -1) {
				perror(snddevice->string);
				Com_Printf("SNDDMA_Init: Could not set sound fragments");
/* NOMMAP - jaq
		Com_Printf("SNDDMA_Init: Sorry, but your soundcard doesn't support trigger or mmap. (%08x)\n", caps);
*/
				close(audio_fd);
				audio_fd = -1;
				return 0;
			}
		}
	}
/* NOMMAP - jaq
    if (ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &info)==-1)
    {   
        perror("GETOSPACE");
		Com_Printf("SNDDMA_Init: GETOSPACE ioctl failed.\n");
		close(audio_fd);
		audio_fd = -1;
		return 0;
    }
*/
	
// set sample bits & speed

    dma.samplebits = (int)sndbits->value;
	if (dma.samplebits != 16 && dma.samplebits != 8)
    {
        ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &fmt);
        if (fmt & AFMT_S16_NE) dma.samplebits = 16;
        else if (fmt & AFMT_U8) dma.samplebits = 8;
    }

	dma.speed = (int)sndspeed->value;
	if (!dma.speed)
	{
		for (i=0 ; i<sizeof(tryrates)/4 ; i++)
			if (!ioctl(audio_fd, SNDCTL_DSP_SPEED, &tryrates[i]))
				break;
		dma.speed = tryrates[i];
	}

	dma.channels = (int)sndchannels->value;
	if (dma.channels < 1 || dma.channels > 2)
		dma.channels = 2;

	if (mmapped) {
		dma.samples = info.fragstotal * info.fragsize / (dma.samplebits/8);
		dma.submission_chunk = 1;

		// memory map the dma buffer

		if (!dma.buffer)
			dma.buffer = (unsigned char *) mmap(NULL, info.fragstotal
				* info.fragsize, PROT_WRITE, MAP_FILE|MAP_SHARED, audio_fd, 0);
		if (!dma.buffer || dma.buffer == MAP_FAILED) {
			perror(snddevice->string);
			Com_Printf("SNDDMA_Init: Could not mmap %s.\n", snddevice->string);
			close(audio_fd);
			audio_fd = -1;
			return 0;
		}
	}

	tmp = 0;
	if (dma.channels == 2)
		tmp = 1;
    rc = ioctl(audio_fd, SNDCTL_DSP_STEREO, &tmp);
    if (rc < 0)
    {
		perror(snddevice->string);
		Com_Printf("SNDDMA_Init: Could not set %s to stereo=%d.", snddevice->string, dma.channels);
		close(audio_fd);
		audio_fd = -1;
        return 0;
    }

	if (tmp)
		dma.channels = 2;
	else
		dma.channels = 1;

    if (dma.samplebits == 16)
    {
        rc = AFMT_S16_NE;
        rc = ioctl(audio_fd, SNDCTL_DSP_SETFMT, &rc);
        if (rc < 0)
		{
			perror(snddevice->string);
			Com_Printf("SNDDMA_Init: Could not support 16-bit data.  Try 8-bit.\n");
			close(audio_fd);
			audio_fd = -1;
			return 0;
		}
    }
    else if (dma.samplebits == 8)
    {
        rc = AFMT_U8;
        rc = ioctl(audio_fd, SNDCTL_DSP_SETFMT, &rc);
        if (rc < 0)
		{
			perror(snddevice->string);
			Com_Printf("SNDDMA_Init: Could not support 8-bit data.\n");
			close(audio_fd);
			audio_fd = -1;
			return 0;
		}
    }
	else
	{
		perror(snddevice->string);
		Com_Printf("SNDDMA_Init: %d-bit sound not supported.", dma.samplebits);
		close(audio_fd);
		audio_fd = -1;
		return 0;
	}

	rc = ioctl(audio_fd, SNDCTL_DSP_SPEED, &dma.speed);
	if (rc < 0)
	{
		perror(snddevice->string);
		Com_Printf("SNDDMA_Init: Could not set %s speed to %d.", snddevice->string, dma.speed);
		close(audio_fd);
		audio_fd = -1;
		return 0;
	}

// toggle the trigger & start her up

	if (!mmapped) {
		dma.submission_chunk = AUDIOBUFFERSIZE;
		dma.samples = AUDIOBUFFERS * dma.submission_chunk * dma.channels;
		dma.samplepos = 0;
		
		if ((dma.buffer = malloc(dma.samples * (dma.samplebits/8))) == 0) {
			perror(snddevice->string);
			Com_Printf("Could not allocate shm->buffer");
			close(audio_fd);
			audio_fd = -1;
			return 0;
		}

		snd_inited = 1;

		pthread_create(&audio, 0L, thesound, 0L);
	} else {
	    tmp = 0;
    	rc  = ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &tmp);
		if (rc < 0) {
			perror(snddevice->string);
			Com_Printf("SNDDMA_Init: Could not toggle. (1)\n");
			close(audio_fd);
			audio_fd = -1;
			return 0;
		}
    	tmp = PCM_ENABLE_OUTPUT;
	    rc = ioctl(audio_fd, SNDCTL_DSP_SETTRIGGER, &tmp);
		if (rc < 0) {
			perror(snddevice->string);
			Com_Printf("SNDDMA_Init: Could not toggle. (2)\n");
			close(audio_fd);
			audio_fd = -1;
			return 0;
		}

		dma.samplepos = 0;
		snd_inited = 1;
	}
	return 1;
}

int SNDDMA_GetDMAPos(void)
{
	struct count_info count;

	if (!snd_inited) return 0;

	if (!mmapped)
		return (frags_sent * FRAGSIZE) / (dma.samplebits/8) + FRAGSIZE/16;

	if (ioctl(audio_fd, SNDCTL_DSP_GETOPTR, &count)==-1)
	{
		perror(snddevice->string);
		Com_Printf("SNDDMA_GetDMAPos: GETOPTR failed.\n");
		close(audio_fd);
		audio_fd = -1;
		snd_inited = 0;
		return 0;
	}
//	dma.samplepos = (count.bytes / (dma.samplebits / 8)) & (dma.samples-1);
//	fprintf(stderr, "%d    \r", count.ptr);
	dma.samplepos = count.ptr / (dma.samplebits / 8);

	return dma.samplepos;
}

void SNDDMA_Shutdown(void) {
#if 0
	if (snd_inited)
	{
		close(audio_fd);
		audio_fd = -1;
		snd_inited = 0;
	}
#endif
	if (snd_inited) {
		if (!mmapped) {
			snd_inited = 0L;
			pthread_join(audio, 0L);

			if (dma.buffer) {
				free(dma.buffer);
				dma.buffer = 0L;
			}
		}

		/* FIXME: use munmap() ? */
		close(audio_fd);
		audio_fd = -1;
		snd_inited = 0;
	}
}

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

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

void SNDDMA_BeginPainting (void)
{
}