/* Extended Module Player
 * Copyright (C) 1996-1999 Claudio Matsuoka and Hipolito Carraro Jr
 *
 * This file is part of the Extended Module Player and is distributed
 * under the terms of the GNU General Public License. See doc/COPYING
 * for more information.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

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

#if defined(HAVE_SYS_SOUNDCARD_H)
#include <sys/soundcard.h>
#elif defined(HAVE_MACHINE_SOUNDCARD_H)
#include <machine/soundcard.h>
#endif

#include "driver.h"
#include "mixer.h"

static int audio_fd;

static void from_fmt (struct xmp_control *, int);
static int to_fmt (struct xmp_control *);
static void setaudio (struct xmp_control *);
static int init (struct xmp_control *);
static void shutdown (void);
static void bufdump (int);
static void flush (void);

static void dummy () { }

static char *help[] = {
    "frag=num,size", "Set the number and size of fragments",
    "dev=<device_name>", "Audio device to use (default /dev/dsp)",
    "nosync", "Don't flush OSS buffers between modules",
#ifdef HAVE_AUDIO_BUF_INFO
    "voxware", "For VoxWare 2.90 (used in Linux 1.2.13)",
#endif
    NULL
};

struct xmp_drv_info drv_oss_mix = {
    "oss_mix",		/* driver ID */
    "OSS PCM audio",	/* driver description */
    help,		/* help */
    init,		/* init */
    shutdown,		/* shutdown */
    xmp_smix_numvoices,	/* numvoices */
    dummy,		/* voicepos */
    xmp_smix_echoback,	/* echoback */
    dummy,		/* setpatch */
    xmp_smix_setvol,	/* setvol */
    dummy,		/* setnote */
    xmp_smix_setpan,	/* setpan */
    dummy,		/* setbend */
    dummy,		/* seteffect */
    dummy,		/* starttimer */
    flush,		/* stctlimer */
    dummy,		/* reset */
    bufdump,		/* bufdump */
    dummy,		/* bufwipe */
    dummy,		/* clearmem */
    dummy,		/* sync */
    xmp_smix_writepatch,/* writepatch */
    xmp_smix_getmsg,	/* getmsg */
    NULL
};

static char *dev_audio = "/dev/dsp";
static int fragnum, fragsize;
static int do_sync = 1;
#ifdef HAVE_AUDIO_BUF_INFO
static int voxware = 0;		/* For Linux 1.2.13 */
#endif


static int to_fmt (struct xmp_control *ctl)
{
    int fmt;

    if (!ctl->resol)
	return AFMT_MU_LAW;

    if (ctl->resol == 8)
	fmt = AFMT_U8 | AFMT_S8;
    else {
#ifdef WORDS_BIGENDIAN
	fmt = AFMT_S16_BE | AFMT_U16_BE;
#else
	fmt = AFMT_S16_LE | AFMT_U16_LE;
#endif
    }
    if (ctl->outfmt & XMP_FMT_UNS)
	fmt &= AFMT_U8 | AFMT_U16_LE | AFMT_U16_BE;
    else
	fmt &= AFMT_S8 | AFMT_S16_LE | AFMT_S16_BE;

    return fmt;
}


static void from_fmt (struct xmp_control *ctl, int outfmt)
{
    if (outfmt & AFMT_MU_LAW) {
	ctl->resol = 0;
	return;
    }

    if (outfmt & (AFMT_S16_LE | AFMT_S16_BE | AFMT_U16_LE | AFMT_U16_BE))
	ctl->resol = 16;
    else
	ctl->resol = 8;

    if (outfmt & (AFMT_U8 | AFMT_U16_LE | AFMT_U16_BE))
	ctl->outfmt |= XMP_FMT_UNS;
    else
	ctl->outfmt &= ~XMP_FMT_UNS;

    if (outfmt & (AFMT_S16_BE | AFMT_U16_BE))
	ctl->outfmt |= XMP_FMT_BIGEND;
    else
	ctl->outfmt &= ~XMP_FMT_BIGEND;
}


static void setaudio (struct xmp_control *ctl)
{
    static int fragset = 0;
    int frag = 0;
    int fmt;

    frag = (fragnum << 16) + fragsize;

    fmt = to_fmt (ctl);
    ioctl (audio_fd, SNDCTL_DSP_SETFMT, &fmt);
    from_fmt (ctl, fmt);

    fmt = !(ctl->outfmt & XMP_FMT_MONO);
    ioctl (audio_fd, SNDCTL_DSP_STEREO, &fmt);
    if (fmt)
	ctl->outfmt &= ~XMP_FMT_MONO;
    else
	ctl->outfmt |= XMP_FMT_MONO;

    ioctl (audio_fd, SNDCTL_DSP_SPEED, &ctl->freq);

    /* Set the fragments only once */
    if (!fragset) {
	if (fragnum && fragsize)
	    ioctl (audio_fd, SNDCTL_DSP_SETFRAGMENT, &frag);
	fragset++;
    }
}


static int init (struct xmp_control *ctl)
{
#ifdef HAVE_AUDIO_BUF_INFO
    audio_buf_info info;
    static char buf[80];
#endif
    char *token, **parm;
    int i = 1024;

    parm_init ();
    chkparm2 ("frag", "%d,%d", &fragnum, &i);
    chkparm1 ("dev", dev_audio = token);
#ifdef HAVE_AUDIO_BUF_INFO
    chkparm1 ("voxware", voxware = 1);
#endif
    chkparm1 ("nosync", do_sync = 0);
    parm_end ();

    for (fragsize = 0; i >>= 1; fragsize++);
    if (fragsize < 4)
	fragsize = 4;
    if (fragnum > 1)
	fragnum--;

    if ((audio_fd = open (dev_audio, O_WRONLY)) == -1)
	return XMP_ERR_DINIT;

    setaudio (ctl);

#ifdef HAVE_AUDIO_BUF_INFO
    if (!voxware) {
	if (ioctl (audio_fd, SNDCTL_DSP_GETOSPACE, &info) == 0) {
	    snprintf (buf, 80, "%s [%d fragments of %d bytes]",
		drv_oss_mix.description, info.fragstotal, info.fragsize);
	    drv_oss_mix.description = buf;
	}
    }
#endif

    return xmp_smix_on (ctl);
}


/* Build and write one tick (one PAL frame or 1/50 s in standard vblank
 * timed mods) of audio data to the output device.
 */
static void bufdump (int i)
{
    int j;
    void *b;

    /* Doesn't work if EINTR -- reported by Ruda Moura <ruda@helllabs.org> */
    /* for (; i -= write (audio_fd, xmp_smix_buffer (), i); ); */

    b = xmp_smix_buffer ();
    while (i) {
	if ((j = write (audio_fd, b, i)) > 0) {
	    i -= j;
	    (char *)b += j;
	} else
	    break;
    };
}


static void shutdown ()
{
    xmp_smix_off ();
    close (audio_fd);
}


static void flush ()
{
    if (!do_sync)
	return;

    ioctl (audio_fd, SNDCTL_DSP_SYNC);
}
