/*
	snd_alsa_0_5.c

	Support for ALSA 0.5, the old stable version of ALSA.

	Copyright (C) 1999,2000  contributors of the QuakeForge project
	Please see the file "AUTHORS" for a list of contributors

	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:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
static const char rcsid[] = 
	"$Id$";

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
# include <sys/ioctl.h>
#endif
#ifdef HAVE_SYS_MMAN_H
# include <sys/mman.h>
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#ifdef HAVE_SYS_SOUNDCARD_H
# include <sys/soundcard.h>
#elif defined HAVE_LINUX_SOUNDCARD_H
# include <linux/soundcard.h>
#elif HAVE_MACHINE_SOUNDCARD_H
# include <machine/soundcard.h>
#endif

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/asoundlib.h>
#include <sys/types.h>

#include "QF/cvar.h"
#include "QF/plugin.h"
#include "QF/qargs.h"
#include "QF/sound.h"
#include "QF/sys.h"

#ifndef MAP_FAILED
# define MAP_FAILED ((void*)-1)
#endif

static int  snd_inited;

static snd_pcm_t *pcm_handle;
static struct snd_pcm_channel_info cinfo;
static struct snd_pcm_channel_params params;
static struct snd_pcm_channel_setup setup;
static snd_pcm_mmap_control_t *mmap_control = NULL;
static char *mmap_data = NULL;
static int  card = -1, dev = -1;
static int snd_blocked = 0;
static volatile dma_t sn;

static cvar_t     *snd_stereo;
static cvar_t     *snd_rate;
static cvar_t     *snd_device;
static cvar_t     *snd_bits;

static plugin_t           plugin_info;
static plugin_data_t      plugin_info_data;
static plugin_funcs_t     plugin_info_funcs;
static general_data_t     plugin_info_general_data;
static general_funcs_t    plugin_info_general_funcs;
static snd_output_data_t       plugin_info_snd_output_data;
static snd_output_funcs_t      plugin_info_snd_output_funcs;


static void
SNDDMA_Init_Cvars (void)
{
	snd_stereo = Cvar_Get ("snd_stereo", "1", CVAR_ROM, NULL,
						   "sound stereo output");
	snd_rate = Cvar_Get ("snd_rate", "0", CVAR_ROM, NULL,
						 "sound playback rate. 0 is system default");
	snd_device = Cvar_Get ("snd_device", "", CVAR_ROM, NULL,
						   "sound device. \"\" is system default");
	snd_bits = Cvar_Get ("snd_bits", "0", CVAR_ROM, NULL,
						 "sound sample depth. 0 is system default");
}

static int
check_card (int card)
{
	int			rc;
	snd_ctl_t  *handle;
	snd_ctl_hw_info_t info;

	if ((rc = snd_ctl_open (&handle, card)) < 0) {
		Sys_Printf ("Error: control open (%i): %s\n", card, snd_strerror (rc));
		return rc;
	}
	if ((rc = snd_ctl_hw_info (handle, &info)) < 0) {
		Sys_Printf ("Error: control hardware info (%i): %s\n", card,
					snd_strerror (rc));
		snd_ctl_close (handle);
		return rc;
	}
	snd_ctl_close (handle);
	if (dev == -1) {
		for (dev = 0; dev < info.pcmdevs; dev++) {
			if ((rc = snd_pcm_open (&pcm_handle, card, dev,
									SND_PCM_OPEN_PLAYBACK
									| SND_PCM_OPEN_NONBLOCK)) == 0) {
				return 0;
			}
		}
	} else {
		if (dev >= 0 && dev < info.pcmdevs) {
			if ((rc = snd_pcm_open (&pcm_handle, card, dev,
									SND_PCM_OPEN_PLAYBACK
									| SND_PCM_OPEN_NONBLOCK)) == 0) {
				return 0;
			}
		}
	}
	return 1;
}

static qboolean
SNDDMA_Init (void)
{
	char	   *err_msg = "";
	int			bps, frag_size, i;
	int			format = -1, rate = -1, stereo = -1, rc = 0;
	unsigned int mask;

	mask = snd_cards_mask ();
	if (!mask) {
		Sys_Printf ("No sound cards detected\n");
		return 0;
	}
	if (snd_device->string[0]) {
		sscanf (snd_device->string, "%d,%d", &card, &dev);
	}
	if (snd_bits->int_val) {
		i = snd_bits->int_val;
		if (i == 16) {
			format = SND_PCM_SFMT_S16_LE;
		} else if (i == 8) {
			format = SND_PCM_SFMT_U8;
		} else {
			Sys_Printf ("Error: invalid sample bits: %d\n", i);
			return 0;
		}
	}
	if (snd_rate->int_val) {
		rate = snd_rate->int_val;
		if (rate != 44100 && rate != 22050 && rate != 11025) {
			Sys_Printf ("Error: invalid sample rate: %d\n", rate);
			return 0;
		}
	}
	stereo = snd_stereo->int_val;
	if (card == -1) {
		for (card = 0; card < SND_CARDS; card++) {
			if (!(mask & (1 << card)))
				continue;
			rc = check_card (card);
			if (rc < 0)
				return 0;
			if (!rc)
				goto dev_openned;
		}
	} else {
		if (dev == -1) {
			rc = check_card (card);
			if (rc < 0)
				return 0;
			if (!rc)
				goto dev_openned;
		} else {
			if ((rc = snd_pcm_open (&pcm_handle, card, dev,
									SND_PCM_OPEN_PLAYBACK
									| SND_PCM_OPEN_NONBLOCK)) < 0) {
				Sys_Printf ("Error: audio open error: %s\n",
							snd_strerror (rc));
				return 0;
			}
			goto dev_openned;
		}
	}
	Sys_Printf ("Error: audio open error: %s\n", snd_strerror (rc));
	return 0;

  dev_openned:
	Sys_Printf ("Using card %d, device %d.\n", card, dev);
	memset (&cinfo, 0, sizeof (cinfo));
	cinfo.channel = SND_PCM_CHANNEL_PLAYBACK;
	snd_pcm_channel_info (pcm_handle, &cinfo);
	Sys_Printf ("%08x %08x %08x\n", cinfo.flags, cinfo.formats, cinfo.rates);
	if ((rate == -1 || rate == 44100) && cinfo.rates & SND_PCM_RATE_44100) {
		rate = 44100;
		frag_size = 512;				/* assuming stereo 8 bit */
	} else if ((rate == -1 || rate == 22050)
			   && cinfo.rates & SND_PCM_RATE_22050) {
		rate = 22050;
		frag_size = 256;				/* assuming stereo 8 bit */
	} else if ((rate == -1 || rate == 11025)
			   && cinfo.rates & SND_PCM_RATE_11025) {
		rate = 11025;
		frag_size = 128;				/* assuming stereo 8 bit */
	} else {
		Sys_Printf ("ALSA: desired rates not supported\n");
		goto error_2;
	}
	if ((format == -1 || format == SND_PCM_SFMT_S16_LE)
		&& cinfo.formats & SND_PCM_FMT_S16_LE) {
		format = SND_PCM_SFMT_S16_LE;
		bps = 16;
		frag_size *= 2;
	} else if ((format == -1 || format == SND_PCM_SFMT_U8)
			   && cinfo.formats & SND_PCM_FMT_U8) {
		format = SND_PCM_SFMT_U8;
		bps = 8;
	} else {
		Sys_Printf ("ALSA: desired formats not supported\n");
		goto error_2;
	}
	if (stereo && cinfo.max_voices >= 2) {
		stereo = 1;
	} else {
		stereo = 0;
		frag_size /= 2;
	}

//	err_msg="audio flush";
//	if ((rc=snd_pcm_channel_flush(pcm_handle, SND_PCM_CHANNEL_PLAYBACK))<0)
//		goto error;
	err_msg = "audio munmap";
	if ((rc = snd_pcm_munmap (pcm_handle, SND_PCM_CHANNEL_PLAYBACK)) < 0)
		goto error;

	memset (&params, 0, sizeof (params));
	params.channel = SND_PCM_CHANNEL_PLAYBACK;
	params.mode = SND_PCM_MODE_BLOCK;
	params.format.interleave = 1;
	params.format.format = format;
	params.format.rate = rate;
	params.format.voices = stereo + 1;
	params.start_mode = SND_PCM_START_GO;
	params.stop_mode = SND_PCM_STOP_ROLLOVER;
	params.buf.block.frag_size = frag_size;
	params.buf.block.frags_min = 1;
	params.buf.block.frags_max = -1;
//	err_msg="audio flush";
//	if ((rc=snd_pcm_channel_flush(pcm_handle, SND_PCM_CHANNEL_PLAYBACK))<0)
//		goto error;
	err_msg = "audio params";
	if ((rc = snd_pcm_channel_params (pcm_handle, &params)) < 0)
		goto error;

	err_msg = "audio mmap";
	if (
		(rc =
		 snd_pcm_mmap (pcm_handle, SND_PCM_CHANNEL_PLAYBACK, &mmap_control,
					   (void **) &mmap_data)) < 0)
		goto error;
	err_msg = "audio prepare";
	if ((rc = snd_pcm_plugin_prepare (pcm_handle, SND_PCM_CHANNEL_PLAYBACK)) <
		0) goto error;

	memset (&setup, 0, sizeof (setup));
	setup.mode = SND_PCM_MODE_BLOCK;
	setup.channel = SND_PCM_CHANNEL_PLAYBACK;
	err_msg = "audio setup";
	if ((rc = snd_pcm_channel_setup (pcm_handle, &setup)) < 0)
		goto error;

	shm = &sn;
	memset ((dma_t *) shm, 0, sizeof (*shm));
	shm->splitbuffer = 0;
	shm->channels = setup.format.voices;
	shm->submission_chunk = 128;		// don't mix less than this #
	shm->samplepos = 0;					// in mono samples
	shm->samplebits = setup.format.format == SND_PCM_SFMT_S16_LE ? 16 : 8;
	shm->samples = setup.buf.block.frags * setup.buf.block.frag_size /
		(shm->samplebits / 8);	// mono samples in buffer
	shm->speed = setup.format.rate;
	shm->buffer = (unsigned char *) mmap_data;
	Sys_Printf ("%5d stereo\n", shm->channels - 1);
	Sys_Printf ("%5d samples\n", shm->samples);
	Sys_Printf ("%5d samplepos\n", shm->samplepos);
	Sys_Printf ("%5d samplebits\n", shm->samplebits);
	Sys_Printf ("%5d submission_chunk\n", shm->submission_chunk);
	Sys_Printf ("%5d speed\n", shm->speed);
	Sys_Printf ("0x%x dma buffer\n", (int) shm->buffer);
	Sys_Printf ("%5d total_channels\n", total_channels);

	snd_inited = 1;
	return 1;
  error:
	Sys_Printf ("Error: %s: %s\n", err_msg, snd_strerror (rc));
  error_2:
	snd_pcm_close (pcm_handle);
	return 0;
}

static int
SNDDMA_GetDMAPos (void)
{
	if (!snd_inited)
		return 0;
	shm->samplepos = (mmap_control->status.frag_io + 1) *
		setup.buf.block.frag_size / (shm->samplebits / 8);
	return shm->samplepos;
}

static void
SNDDMA_Shutdown (void)
{
	if (snd_inited) {
		snd_pcm_close (pcm_handle);
		snd_inited = 0;
	}
}

/*
	SNDDMA_Submit

	Send sound to device if buffer isn't really the dma buffer
*/
static void
SNDDMA_Submit (void)
{
	int		rc, e, i, s;
	int		count = (*plugin_info_snd_output_data.paintedtime -
					 *plugin_info_snd_output_data.soundtime);

	if (snd_blocked)
		return;
	count += setup.buf.block.frag_size - 1;
	count /= setup.buf.block.frag_size;
	s = *plugin_info_snd_output_data.soundtime / setup.buf.block.frag_size;
	e = s + count;
	for (i = s; i < e; i++)
		mmap_control->fragments[i % setup.buf.block.frags].data = 1;
	switch (mmap_control->status.status) {
		case SND_PCM_STATUS_PREPARED:
			if ((rc = snd_pcm_channel_go (pcm_handle,
										  SND_PCM_CHANNEL_PLAYBACK)) < 0) {
				Sys_Error ("unable to start playback. %s",
						   snd_strerror (rc));
			}
			break;
		case SND_PCM_STATUS_RUNNING:
			break;
		case SND_PCM_STATUS_UNDERRUN:
			if ((rc = snd_pcm_plugin_prepare (pcm_handle,
											  SND_PCM_CHANNEL_PLAYBACK)) < 0) {
				Sys_Error ("underrun: playback channel prepare error. %s",
						   snd_strerror (rc));
			}
			break;
		default:
			break;
	}
}

static void
SNDDMA_BlockSound (void)
{
	if (++snd_blocked == 1)
		snd_pcm_playback_pause (pcm_handle, 1);
}

static void
SNDDMA_UnblockSound (void)
{
	if (!snd_blocked)
		return;
	if (!--snd_blocked)
		snd_pcm_playback_pause (pcm_handle, 0);
}

plugin_t *
PLUGIN_INFO(snd_output, alsa0_5) (void) {
	plugin_info.type = qfp_snd_output;
	plugin_info.api_version = QFPLUGIN_VERSION;
	plugin_info.plugin_version = "0.1";
	plugin_info.description = "ALSA 0.5.x digital output";
	plugin_info.copyright = "Copyright (C) 1996-1997 id Software, Inc.\n"
		"Copyright (C) 1999,2000,2001  contributors of the QuakeForge "
		"project\n"
		"Please see the file \"AUTHORS\" for a list of contributors";
	plugin_info.functions = &plugin_info_funcs;
	plugin_info.data = &plugin_info_data;

	plugin_info_data.general = &plugin_info_general_data;
	plugin_info_data.input = NULL;
	plugin_info_data.snd_output = &plugin_info_snd_output_data;

	plugin_info_funcs.general = &plugin_info_general_funcs;
	plugin_info_funcs.input = NULL;
	plugin_info_funcs.snd_output = &plugin_info_snd_output_funcs;

	plugin_info_general_funcs.p_Init = SNDDMA_Init_Cvars;
	plugin_info_general_funcs.p_Shutdown = NULL;
	plugin_info_snd_output_funcs.pS_O_Init = SNDDMA_Init;
	plugin_info_snd_output_funcs.pS_O_Shutdown = SNDDMA_Shutdown;
	plugin_info_snd_output_funcs.pS_O_GetDMAPos = SNDDMA_GetDMAPos;
	plugin_info_snd_output_funcs.pS_O_Submit = SNDDMA_Submit;
	plugin_info_snd_output_funcs.pS_O_BlockSound = SNDDMA_BlockSound;
	plugin_info_snd_output_funcs.pS_O_UnblockSound = SNDDMA_UnblockSound;

	return &plugin_info;
}