/*
 * Copyright (c) 2008-2014 Alexandre Ratchov <alex@caoua.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <fcntl.h>
#include <errno.h>
#include <poll.h>
#include <signal.h>
#include <sndio.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "abuf.h"
#include "afile.h"
#include "dsp.h"
#include "sysex.h"
#include "utils.h"

/*
 * masks to extract command and channel of status byte
 */
#define MIDI_CMDMASK	0xf0
#define MIDI_CHANMASK	0x0f

/*
 * MIDI status bytes of voice messages
 */
#define MIDI_NOFF	0x80		/* note off */
#define MIDI_NON	0x90		/* note on */
#define MIDI_KAT	0xa0		/* key after touch */
#define MIDI_CTL	0xb0		/* controller */
#define MIDI_PC		0xc0		/* program change */
#define MIDI_CAT	0xd0		/* channel after touch */
#define MIDI_BEND	0xe0		/* pitch bend */
#define MIDI_ACK	0xfe		/* active sensing message */

/*
 * MIDI controller numbers
 */
#define MIDI_CTL_VOL	7

/*
 * Max coarse value
 */
#define MIDI_MAXCTL	127

/*
 * MIDI status bytes for sysex
 */
#define MIDI_SX_START	0xf0
#define MIDI_SX_STOP	0xf7

/*
 * audio device defaults
 */
#define DEFAULT_RATE		48000
#define DEFAULT_BUFSZ_MS	200

struct slot {
	struct slot *next;		/* next on the play list */
	int vol;			/* dynamic range */
	int volctl;			/* volume in the 0..127 range */
	struct abuf buf;		/* file i/o buffer */
	int bpf;			/* bytes per frame */
	int cmin, cmax;			/* file channel range */
	struct cmap cmap;		/* channel mapper state */
	struct resamp resamp;		/* resampler state */
	struct conv conv;		/* format encoder state */
	int join;			/* channel join factor */
	int expand;			/* channel expand factor */
	void *resampbuf, *convbuf;	/* conversion tmp buffers */
	int dup;			/* mono-to-stereo and alike */
	int round;			/* slot-side block size */
	int mode;			/* MODE_{PLAY,REC} */
#define SLOT_CFG	0		/* buffers not allocated yet */
#define SLOT_INIT	1		/* not trying to do anything */
#define SLOT_RUN	2		/* playing/recording */
#define SLOT_STOP	3		/* draining (play only) */
	int pstate;			/* one of above */
	struct afile afile;			/* file desc & friends */
};

/*
 * device properties
 */
unsigned int dev_mode;			/* bitmap of SIO_{PLAY,REC} */
unsigned int dev_bufsz;			/* device buffer size */
unsigned int dev_round;			/* device block size */
int dev_rate;				/* device sample rate (Hz) */
unsigned int dev_pchan, dev_rchan;	/* play & rec channels count */
adata_t *dev_pbuf, *dev_rbuf;		/* play & rec buffers */
unsigned int dev_mmcpos;		/* last MMC position */
#define DEV_STOP	0		/* stopped */
#define DEV_START	1		/* started */
unsigned int dev_pstate;		/* one of above */
char *dev_name;				/* device sndio(7) name */
char *dev_port;				/* control port sndio(7) name */
struct sio_hdl *dev_sh;			/* device handle */
struct mio_hdl *dev_mh;			/* MIDI control port handle */
unsigned int dev_volctl = MIDI_MAXCTL;	/* master volume */

/*
 * MIDI parser state
 */
#define MIDI_MSGMAX	32		/* max size of MIDI msg */
unsigned char dev_msg[MIDI_MSGMAX];	/* parsed input message */
unsigned int dev_mst;			/* input MIDI running status */
unsigned int dev_mused;			/* bytes used in ``msg'' */
unsigned int dev_midx;			/* current ``msg'' size */
unsigned int dev_mlen;			/* expected ``msg'' length */
unsigned int dev_prime;			/* blocks to write to start */

unsigned int log_level = 1;
volatile sig_atomic_t quit_flag = 0;
struct slot *slot_list = NULL;

/*
 * length of voice and common MIDI messages (status byte included)
 */
unsigned int voice_len[] = { 3, 3, 3, 3, 2, 2, 3 };
unsigned int common_len[] = { 0, 2, 3, 2, 0, 0, 1, 1 };

char usagestr[] = "usage: aucat [-dn] [-b size] "
    "[-c min:max] [-e enc] [-f device] [-h fmt]\n\t"
    "[-i file] [-j flag] [-o file] [-q port] [-r rate] [-v volume]\n";

static void
slot_log(struct slot *s)
{
#ifdef DEBUG
	static char *pstates[] = {
		"cfg", "ini", "run", "stp"
	};
#endif
	log_puts(s->afile.path);
#ifdef DEBUG
	if (log_level >= 3) {
		log_puts(",pst=");
		log_puts(pstates[s->pstate]);
	}
#endif
}

static void
slot_flush(struct slot *s)
{
	int todo, count, n;
	unsigned char *data;

	todo = s->buf.used;
	while (todo > 0) {
		data = abuf_rgetblk(&s->buf, &count);
		if (count > todo)
			count = todo;
		n = afile_write(&s->afile, data, count);
		if (n == 0) {
			slot_log(s);
			log_puts(": can't write, disabled\n");
			s->pstate = SLOT_INIT;
			return;
		}
		abuf_rdiscard(&s->buf, n);
		todo -= n;
	}
}

static void
slot_fill(struct slot *s)
{
	int todo, count, n;
	unsigned char *data;

	todo = s->buf.len;
	while (todo > 0) {
		data = abuf_wgetblk(&s->buf, &count);
		if (count > todo)
			count = todo;
		n = afile_read(&s->afile, data, count);
		if (n == 0) {
#ifdef DEBUG
			if (log_level >= 3) {
				slot_log(s);
				log_puts(": eof reached, stopping\n");
			}
#endif
			s->pstate = SLOT_STOP;
			break;
		}
		abuf_wcommit(&s->buf, n);
		todo -= n;
	}
}

static int
slot_new(char *path, int mode, struct aparams *par, int hdr,
    int cmin, int cmax, int rate, int dup, int vol)
{
	struct slot *s;

	s = xmalloc(sizeof(struct slot));
	if (!afile_open(&s->afile, path, hdr,
		mode == SIO_PLAY ? AFILE_FREAD : AFILE_FWRITE,
		par, rate, cmax - cmin + 1)) {
		xfree(s);
		return 0;
	}
	s->cmin = cmin;
	s->cmax = cmin + s->afile.nch - 1;
	s->dup = dup;
	s->vol = MIDI_TO_ADATA(vol);
	s->mode = mode;
	s->pstate = SLOT_CFG;
	if (log_level >= 2) {
		slot_log(s);
		log_puts(": ");
		log_puts(s->mode == SIO_PLAY ? "play" : "rec");
		log_puts(", chan ");
		log_putu(s->cmin);
		log_puts(":");
		log_putu(s->cmax);
		log_puts(", ");
		log_putu(s->afile.rate);
		log_puts("Hz, ");
		switch (s->afile.fmt) {
		case AFILE_FMT_PCM:
			aparams_log(&s->afile.par);
			break;
		case AFILE_FMT_ULAW:
			log_puts("ulaw");
			break;
		case AFILE_FMT_ALAW:
			log_puts("alaw");
			break;
		case AFILE_FMT_FLOAT:
			log_puts("f32le");
			break;
		}
		if (s->mode == SIO_PLAY && s->afile.endpos >= 0) {
			log_puts(", bytes ");
			log_puti(s->afile.startpos);
			log_puts("..");
			log_puti(s->afile.endpos);
		}
		log_puts("\n");
	}
	s->next = slot_list;
	slot_list = s;
	return 1;
}

static void
slot_init(struct slot *s)
{
	unsigned int slot_nch, bufsz;

#ifdef DEBUG
	if (s->pstate != SLOT_CFG) {
		slot_log(s);
		log_puts(": slot_init: wrong state\n");
		panic();
	}
#endif
	s->bpf = s->afile.par.bps * (s->cmax - s->cmin + 1);
	s->round = (dev_round * s->afile.rate + dev_rate / 2) / dev_rate;

	bufsz = s->round * (dev_bufsz / dev_round);
	bufsz -= bufsz % s->round;
	if (bufsz == 0)
		bufsz = s->round;
	abuf_init(&s->buf, bufsz * s->bpf);
#ifdef DEBUG
	if (log_level >= 3) {
		slot_log(s);
		log_puts(": allocated ");
		log_putu(bufsz);
		log_puts(" frame buffer\n");
	}
#endif

	slot_nch = s->cmax - s->cmin + 1;
	s->convbuf = NULL;
	s->resampbuf = NULL;
	s->join = 1;
	s->expand = 1;
	if (s->mode & SIO_PLAY) {
		if (s->dup) {
			if (dev_pchan > slot_nch)
				s->expand = dev_pchan / slot_nch;
			else if (dev_pchan < slot_nch)
				s->join = slot_nch / dev_pchan;
		}
		cmap_init(&s->cmap,
		    s->cmin, s->cmax,
		    s->cmin, s->cmax,
		    0, dev_pchan - 1,
		    0, dev_pchan - 1);
		if (s->afile.fmt != AFILE_FMT_PCM || !aparams_native(&s->afile.par)) {
			dec_init(&s->conv, &s->afile.par, slot_nch);
			s->convbuf =
			    xmalloc(s->round * slot_nch * sizeof(adata_t));
		}
		if (s->afile.rate != dev_rate) {
			resamp_init(&s->resamp, s->round, dev_round,
			    slot_nch);
			s->resampbuf =
			    xmalloc(dev_round * slot_nch * sizeof(adata_t));
		}
	}
	if (s->mode & SIO_REC) {
		if (s->dup) {
			if (dev_rchan > slot_nch)
				s->join = dev_rchan / slot_nch;
			else if (dev_rchan < slot_nch)
				s->expand = slot_nch / dev_rchan;
		}
		cmap_init(&s->cmap,
		    0, dev_rchan - 1,
		    0, dev_rchan - 1,
		    s->cmin, s->cmax,
		    s->cmin, s->cmax);
		if (s->afile.rate != dev_rate) {
			resamp_init(&s->resamp, dev_round, s->round,
			    slot_nch);
			s->resampbuf =
			    xmalloc(dev_round * slot_nch * sizeof(adata_t));
		}
		if (!aparams_native(&s->afile.par)) {
			enc_init(&s->conv, &s->afile.par, slot_nch);
			s->convbuf =
			    xmalloc(s->round * slot_nch * sizeof(adata_t));
		}
	}
	s->pstate = SLOT_INIT;
#ifdef DEBUG
	if (log_level >= 3) {
		slot_log(s);
		log_puts(": chain initialized\n");
	}
#endif
}

static void
slot_start(struct slot *s, unsigned int mmc)
{
	off_t mmcpos;

#ifdef DEBUG
	if (s->pstate != SLOT_INIT) {
		slot_log(s);
		log_puts(": slot_start: wrong state\n");
		panic();
	}
#endif
	mmcpos = ((off_t)mmc * s->afile.rate / MTC_SEC) * s->bpf;
	if (!afile_seek(&s->afile, mmcpos)) {
		s->pstate = SLOT_INIT;
		return;
	}
	s->pstate = SLOT_RUN;
	if (s->mode & SIO_PLAY)
		slot_fill(s);
#ifdef DEBUG
	if (log_level >= 2) {
		slot_log(s);
		log_puts(": started\n");
	}
#endif
}

static void
slot_stop(struct slot *s)
{
	if (s->pstate == SLOT_INIT)
		return;
	if (s->mode & SIO_REC)
		slot_flush(s);
	if (s->mode & SIO_PLAY)
		s->buf.used = s->buf.start = 0;
	s->pstate = SLOT_INIT;
#ifdef DEBUG
	if (log_level >= 2) {
		slot_log(s);
		log_puts(": stopped\n");
	}
#endif
}

static void
slot_del(struct slot *s)
{
	struct slot **ps;

	if (s->pstate != SLOT_CFG) {
		slot_stop(s);
		afile_close(&s->afile);
#ifdef DEBUG
		if (log_level >= 3) {
			slot_log(s);
			log_puts(": closed\n");
		}
#endif
		abuf_done(&s->buf);
		if (s->resampbuf)
			xfree(s->resampbuf);
		if (s->convbuf)
			xfree(s->convbuf);
	}
	for (ps = &slot_list; *ps != s; ps = &(*ps)->next)
		; /* nothing */
	*ps = s->next;
	xfree(s);
}

static int 
play_filt_resamp(struct slot *s, void *res_in, void *out, int todo)
{
	int i, offs, vol, nch;
	void *in;

	if (s->resampbuf) {
		todo = resamp_do(&s->resamp,
		    res_in, s->resampbuf, todo);
		in = s->resampbuf;
	} else
		in = res_in;

	nch = s->cmap.nch;
	vol = s->vol / s->join; /* XXX */
	cmap_add(&s->cmap, in, out, vol, todo);

	offs = 0;
	for (i = s->join - 1; i > 0; i--) {
		offs += nch;
		cmap_add(&s->cmap, (adata_t *)in + offs, out, vol, todo);
	}
	offs = 0;
	for (i = s->expand - 1; i > 0; i--) {
		offs += nch;
		cmap_add(&s->cmap, in, (adata_t *)out + offs, vol, todo);
	}
	return todo;
}

static int 
play_filt_dec(struct slot *s, void *in, void *out, int todo)
{
	void *tmp;

	tmp = s->convbuf;
	if (tmp) {
		switch (s->afile.fmt) {
		case AFILE_FMT_PCM:
			dec_do(&s->conv, in, tmp, todo);
			break;
		case AFILE_FMT_ULAW:
			dec_do_ulaw(&s->conv, in, tmp, todo, 0);
			break;
		case AFILE_FMT_ALAW:
			dec_do_ulaw(&s->conv, in, tmp, todo, 1);
			break;
		case AFILE_FMT_FLOAT:
			dec_do_float(&s->conv, in, tmp, todo);
			break;
		}
	}
	return play_filt_resamp(s, tmp ? tmp : in, out, todo);
}

/*
 * Mix as many as possible frames (but not more than a block) from the
 * slot buffer to the given location. Return the number of frames mixed
 * in the output buffer
 */
static int
slot_mix_badd(struct slot *s, adata_t *odata)
{
	adata_t *idata;
	int icount, todo, done;

	idata = (adata_t *)abuf_rgetblk(&s->buf, &icount);
	todo = icount / s->bpf;
	if (todo > s->round)
		todo = s->round;
#ifdef DEBUG
	if (todo == 0) {
		log_puts("slot_mix_badd: not enough data\n");
		panic();
	}
#endif
	done = play_filt_dec(s, idata, odata, todo);
	abuf_rdiscard(&s->buf, todo * s->bpf);
	return done;
}

static int 
rec_filt_resamp(struct slot *s, void *in, void *res_out, int todo)
{
	int i, vol, offs, nch;
	void *out = res_out;

	out = (s->resampbuf) ? s->resampbuf : res_out;

	nch = s->cmap.nch;
	vol = ADATA_UNIT / s->join;
	cmap_copy(&s->cmap, in, out, vol, todo);

	offs = 0;
	for (i = s->join - 1; i > 0; i--) {
		offs += nch;
		cmap_add(&s->cmap, (adata_t *)in + offs, out, vol, todo);
	}
	offs = 0;
	for (i = s->expand - 1; i > 0; i--) {
		offs += nch;
		cmap_copy(&s->cmap, in, (adata_t *)out + offs, vol, todo);
	}
	if (s->resampbuf) {
		todo = resamp_do(&s->resamp,
		    s->resampbuf, res_out, todo);
	}
	return todo;
}

static int 
rec_filt_enc(struct slot *s, void *in, void *out, int todo)
{
	void *tmp;

	tmp = s->convbuf;
	todo = rec_filt_resamp(s, in, tmp ? tmp : out, todo);
	if (tmp)
		enc_do(&s->conv, tmp, out, todo);
	return todo;
}

/*
 * Copy "todo" frames from the given buffer to the slot buffer,
 * but not more than a block.
 */
static void
slot_sub_bcopy(struct slot *s, adata_t *idata, int todo)
{
	adata_t *odata;
	int ocount;

	odata = (adata_t *)abuf_wgetblk(&s->buf, &ocount);
#ifdef DEBUG
	if (ocount < s->round * s->bpf) {
		log_puts("slot_sub_bcopy: not enough space\n");
		panic();
	}
#endif
	ocount = rec_filt_enc(s, idata, odata, todo);
	abuf_wcommit(&s->buf, ocount * s->bpf);
}

static int
dev_open(char *dev, int mode, int bufsz, char *port)
{
	int rate, pmax, rmax;
	struct sio_par par;
	struct slot *s;

	if (port) {
		dev_port = port;
		dev_mh = mio_open(dev_port, MIO_IN, 0);
		if (dev_mh == NULL) {
			log_puts(port);
			log_puts(": couldn't open midi port\n");
			return 0;
		}
	} else
		dev_mh = NULL;

	dev_name = dev;
	dev_sh = sio_open(dev, mode, 0);
	if (dev_sh == NULL) {
		log_puts(dev_name);
		log_puts(": couldn't open audio device\n");
		return 0;
	}

	rate = pmax = rmax = 0;
	for (s = slot_list; s != NULL; s = s->next) {
		if (s->afile.rate > rate)
			rate = s->afile.rate;
		if (s->mode == SIO_PLAY) {
			if (s->cmax > pmax)
				pmax = s->cmax;
		}
		if (s->mode == SIO_REC) {
			if (s->cmax > rmax)
				rmax = s->cmax;
		}
	}
	sio_initpar(&par);
	par.bits = ADATA_BITS;
	par.bps = sizeof(adata_t);
	par.msb = 0;
	par.le = SIO_LE_NATIVE;
	if (mode & SIO_PLAY)
		par.pchan = pmax + 1;
	if (mode & SIO_REC)
		par.rchan = rmax + 1;
	par.appbufsz = bufsz > 0 ? bufsz : rate * DEFAULT_BUFSZ_MS / 1000;
	if (!sio_setpar(dev_sh, &par) || !sio_getpar(dev_sh, &par)) {
		log_puts(dev_name);
		log_puts(": couldn't set audio params\n");
		return 0;
	}
	if (par.bits != ADATA_BITS ||
	    par.bps != sizeof(adata_t) ||
	    par.le != SIO_LE_NATIVE ||
	    (par.bps != SIO_BPS(par.bits) && par.msb)) {
		log_puts(dev_name);
		log_puts(": unsupported audio params\n");
		return 0;
	}
	dev_mode = mode;
	dev_rate = par.rate;
	dev_bufsz = par.bufsz;
	dev_round = par.round;
	if (mode & SIO_PLAY) {
		dev_pchan = par.pchan;
		dev_pbuf = xmalloc(sizeof(adata_t) * dev_pchan * dev_round);
	}
	if (mode & SIO_REC) {
		dev_rchan = par.rchan;
		dev_rbuf = xmalloc(sizeof(adata_t) * dev_rchan * dev_round);
	}
	dev_mmcpos = 0;
	dev_pstate = DEV_STOP;
	if (log_level >= 2) {
		log_puts(dev_name);
		log_puts(": ");
		log_putu(dev_rate);
		log_puts("Hz");
		if (dev_mode & SIO_PLAY) {
			log_puts(", play 0:");
			log_puti(dev_pchan - 1);
		}
		if (dev_mode & SIO_REC) {
			log_puts(", rec 0:");
			log_puti(dev_rchan - 1);
		}
		log_puts(", ");
		log_putu(dev_bufsz / dev_round);
		log_puts(" blocks of ");
		log_putu(dev_round);
		log_puts(" frames\n");
	}
	return 1;
}

static void
dev_close(void)
{
	sio_close(dev_sh);
	if (dev_mh)
		mio_close(dev_mh);
	if (dev_mode & SIO_PLAY)
		xfree(dev_pbuf);
	if (dev_mode & SIO_REC)
		xfree(dev_rbuf);
}

static void
dev_master(int val)
{
	struct slot *s;
	int mastervol, slotvol;

	mastervol = MIDI_TO_ADATA(dev_volctl);
	for (s = slot_list; s != NULL; s = s->next) {
		slotvol = MIDI_TO_ADATA(val);
		s->vol = ADATA_MUL(mastervol, slotvol);
	}
#ifdef DEBUG
	if (log_level >= 3) {
		log_puts("master volume set to ");
		log_putu(val);
		log_puts("\n");
	}
#endif
}

static void
dev_slotvol(int midich, int val)
{
	struct slot *s;
	int mastervol, slotvol;

	for (s = slot_list; s != NULL; s = s->next) {
		if (midich == 0) {
			mastervol = MIDI_TO_ADATA(dev_volctl);
			slotvol = MIDI_TO_ADATA(val);
			s->vol = ADATA_MUL(mastervol, slotvol);
#ifdef DEBUG
			if (log_level >= 3) {
				slot_log(s);
				log_puts(": volume set to ");
				log_putu(val);
				log_puts("\n");
			}
#endif
			break;
		}
	}
}

/*
 * start all slots simultaneously
 */
static void
dev_mmcstart(void)
{
	struct slot *s;

	if (dev_pstate == DEV_STOP) {
		dev_pstate = DEV_START;
		for (s = slot_list; s != NULL; s = s->next)
			slot_start(s, dev_mmcpos);
		dev_prime = (dev_mode & SIO_PLAY) ? dev_bufsz / dev_round : 0;
		sio_start(dev_sh);
		if (log_level >= 2)
			log_puts("started\n");
	} else {
#ifdef DEBUG
		if (log_level >= 3)
			log_puts("ignoring mmc start\n");
#endif
	}
}

/*
 * stop all slots simultaneously
 */
static void
dev_mmcstop(void)
{
	struct slot *s;

	if (dev_pstate == DEV_START) {
		dev_pstate = DEV_STOP;
		for (s = slot_list; s != NULL; s = s->next)
			slot_stop(s);
		sio_stop(dev_sh);
		if (log_level >= 2)
			log_puts("stopped\n");
	} else {
#ifdef DEBUG
		if (log_level >= 3)
			log_puts("ignored mmc stop\n");
#endif
	}
}

/*
 * relocate all slots simultaneously
 */
static void
dev_mmcloc(unsigned int mmc)
{
	if (dev_mmcpos == mmc)
		return;
	dev_mmcpos = mmc;
	if (log_level >= 2) {
		log_puts("relocated to ");
		log_putu((dev_mmcpos / (MTC_SEC * 3600)) % 24);
		log_puts(":");
		log_putu((dev_mmcpos / (MTC_SEC * 60)) % 60);
		log_puts(":");
		log_putu((dev_mmcpos / (MTC_SEC)) % 60);
		log_puts(".");
		log_putu((dev_mmcpos / (MTC_SEC / 100)) % 100);
		log_puts("\n");
	}
	if (dev_pstate == DEV_START) {
		dev_mmcstop();
		dev_mmcstart();
	}
}

static void
dev_imsg(unsigned char *msg, unsigned int len)
{
	struct sysex *x;
	unsigned int fps, chan;

	if ((msg[0] & MIDI_CMDMASK) == MIDI_CTL && msg[1] == MIDI_CTL_VOL) {
		chan = msg[0] & MIDI_CHANMASK;
		dev_slotvol(chan, msg[2]);
		return;
	}
	x = (struct sysex *)msg;
	if (x->start != SYSEX_START)
		return;
	if (len < SYSEX_SIZE(empty))
		return;
	if (x->type != SYSEX_TYPE_RT)
		return;
	if (x->id0 == SYSEX_CONTROL && x->id1 == SYSEX_MASTER) {
		if (len == SYSEX_SIZE(master))
			dev_master(x->u.master.coarse);
		return;
	}
	if (x->id0 != SYSEX_MMC)
		return;
	switch (x->id1) {
	case SYSEX_MMC_STOP:
		if (len != SYSEX_SIZE(stop))
			return;
		dev_mmcstop();
		break;
	case SYSEX_MMC_START:
		if (len != SYSEX_SIZE(start))
			return;
		dev_mmcstart();
		break;
	case SYSEX_MMC_LOC:
		if (len != SYSEX_SIZE(loc) ||
		    x->u.loc.len != SYSEX_MMC_LOC_LEN ||
		    x->u.loc.cmd != SYSEX_MMC_LOC_CMD)
			return;
		switch (x->u.loc.hr >> 5) {
		case MTC_FPS_24:
			fps = 24;
			break;
		case MTC_FPS_25:
			fps = 25;
			break;
		case MTC_FPS_30:
			fps = 30;
			break;
		default:
			dev_mmcstop();
			return;
		}
		dev_mmcloc((x->u.loc.hr & 0x1f) * 3600 * MTC_SEC +
		    x->u.loc.min * 60 * MTC_SEC +
		    x->u.loc.sec * MTC_SEC +
		    x->u.loc.fr * (MTC_SEC / fps) +
		    x->u.loc.cent * (MTC_SEC / 100 / fps));
		break;
	}
}

/*
 * parse then given data chunk, and calling imsg() for each message
 */
static void
midi_in(unsigned char *idata, int icount)
{
	int i;
	unsigned char c;

	for (i = 0; i < icount; i++) {
		c = *idata++;
		if (c >= 0xf8) {
			/* we don't use reat-time events */
		} else if (c == SYSEX_END) {
			if (dev_mst == SYSEX_START) {
				dev_msg[dev_midx++] = c;
				dev_imsg(dev_msg, dev_midx);
			}
			dev_mst = 0;
			dev_midx = 0;
		} else if (c >= 0xf0) {
			dev_msg[0] = c;
			dev_mlen = common_len[c & 7];
			dev_mst = c;
			dev_midx = 1;
		} else if (c >= 0x80) {
			dev_msg[0] = c;
			dev_mlen = voice_len[(c >> 4) & 7];
			dev_mst = c;
			dev_midx = 1;
		} else if (dev_mst) {
			if (dev_midx == 0 && dev_mst != SYSEX_START)
				dev_msg[dev_midx++] = dev_mst;
			dev_msg[dev_midx++] = c;
			if (dev_midx == dev_mlen) {
				dev_imsg(dev_msg, dev_midx);
				if (dev_mst >= 0xf0)
					dev_mst = 0;
				dev_midx = 0;
			} else if (dev_midx == MIDI_MSGMAX) {
				/* sysex too long */
				dev_mst = 0;
			}
		}
	}
}

static int
slot_list_mix(unsigned int round, unsigned int pchan, adata_t *pbuf)
{
	unsigned int done, n;
	struct slot *s;

	memset(pbuf, 0, pchan * round * sizeof(adata_t));
	done = 0;
	for (s = slot_list; s != NULL; s = s->next) {
		if (s->pstate == SLOT_INIT || !(s->mode & SIO_PLAY))
			continue;
		if (s->pstate == SLOT_STOP && s->buf.used < s->bpf) {
			s->pstate = SLOT_INIT;
#ifdef DEBUG
			if (log_level >= 3) {
				slot_log(s);
				log_puts(": drained, done\n");
			}
#endif
			continue;
		}
		n = slot_mix_badd(s, dev_pbuf);
		if (n > done)
			done = n;
	}
	return done;
}

static int
slot_list_copy(unsigned int count, unsigned int rchan, adata_t *rbuf)
{
	unsigned int done;
	struct slot *s;

	done = 0;
	for (s = slot_list; s != NULL; s = s->next) {
		if (s->pstate == SLOT_INIT || !(s->mode & SIO_REC))
			continue;
		slot_sub_bcopy(s, rbuf, count);
		done = count;
	}
	return done;
}

static void
slot_list_iodo(void)
{
	struct slot *s;

	for (s = slot_list; s != NULL; s = s->next) {
		if (s->pstate != SLOT_RUN)
			continue;
		if ((s->mode & SIO_PLAY) && (s->buf.used == 0))
			slot_fill(s);
		if ((s->mode & SIO_REC) && (s->buf.used == s->buf.len))
			slot_flush(s);
	}
}

static int
offline(void)
{
	unsigned int todo;
	int rate, cmax;
	struct slot *s;

	rate = cmax = 0;
	for (s = slot_list; s != NULL; s = s->next) {
		if (s->afile.rate > rate)
			rate = s->afile.rate;
		if (s->cmax > cmax)
			cmax = s->cmax;
	}
	dev_sh = NULL;
	dev_name = "offline";
	dev_mode = SIO_PLAY | SIO_REC;
	dev_rate = rate;
	dev_bufsz = rate;
	dev_round = rate;
	dev_pchan = dev_rchan = cmax + 1;
	dev_pbuf = dev_rbuf = xmalloc(sizeof(adata_t) * dev_pchan * dev_round);
	dev_pstate = DEV_STOP;
	dev_mmcpos = 0;
	for (s = slot_list; s != NULL; s = s->next)
		slot_init(s);
	for (s = slot_list; s != NULL; s = s->next)
		slot_start(s, 0);
	for (;;) {
		todo = slot_list_mix(dev_round, dev_pchan, dev_pbuf);
		if (todo == 0)
			break;
		slot_list_copy(todo, dev_pchan, dev_pbuf);
		slot_list_iodo();
	}
	xfree(dev_pbuf);
	while (slot_list)
		slot_del(slot_list);
	return 1;
}

static int
playrec_cycle(void)
{
	unsigned int n, todo;
	unsigned char *p;
	int pcnt, rcnt;

#ifdef DEBUG
	if (log_level >= 4) {
		log_puts(dev_name);
		log_puts(": cycle, prime = ");
		log_putu(dev_prime);
		log_puts("\n");
	}
#endif
	pcnt = rcnt = 0;
	if (dev_mode & SIO_REC) {
		if (dev_prime > 0)
			dev_prime--;
		else {
			todo = dev_round * dev_rchan * sizeof(adata_t);
			p = (unsigned char *)dev_rbuf;
			while (todo > 0) {
				n = sio_read(dev_sh, p, todo);
				if (n == 0) {
					log_puts(dev_name);
					log_puts(": failed to read from device\n");
					return 0;
				}
				p += n;
				todo -= n;
			}
			rcnt = slot_list_copy(dev_round, dev_rchan, dev_rbuf);
		}
	}
	if (dev_mode & SIO_PLAY) {
		pcnt = slot_list_mix(dev_round, dev_pchan, dev_pbuf);
		todo = sizeof(adata_t) * dev_pchan * dev_round;
		n = sio_write(dev_sh, dev_pbuf, todo);
		if (n == 0) {
			log_puts(dev_name);
			log_puts(": failed to write to device\n");
			return 0;
		}
	}
	slot_list_iodo();
	return pcnt > 0 || rcnt > 0;
}

static void
sigint(int s)
{
	if (quit_flag)
		_exit(1);
	quit_flag = 1;
}

static int
playrec(char *dev, int mode, int bufsz, char *port)
{
#define MIDIBUFSZ 0x100
	unsigned char mbuf[MIDIBUFSZ];
	struct sigaction sa;
	struct pollfd *pfds;
	struct slot *s;
	int n, ns, nm, ev;

	if (!dev_open(dev, mode, bufsz, port))
		return 0;
	n = sio_nfds(dev_sh);
	if (dev_mh)
		n += mio_nfds(dev_mh);
	pfds = xmalloc(n * sizeof(struct pollfd));
	for (s = slot_list; s != NULL; s = s->next)
		slot_init(s);
	if (dev_mh == NULL)
		dev_mmcstart();
	else {
		if (log_level >= 2)
			log_puts("ready, waiting for mmc messages\n");
	}

	quit_flag = 0;
	sigfillset(&sa.sa_mask);
	sa.sa_flags = SA_RESTART;
	sa.sa_handler = sigint;
	sigaction(SIGINT, &sa, NULL);
	sigaction(SIGTERM, &sa, NULL);
	sigaction(SIGHUP, &sa, NULL);
	while (!quit_flag) {
		if (dev_pstate == DEV_START) {
			ev = 0;
			if (mode & SIO_PLAY)
				ev |= POLLOUT;
			if (mode & SIO_REC)
				ev |= POLLIN;
			ns = sio_pollfd(dev_sh, pfds, ev);
		} else
			ns = 0;
		if (dev_mh)
			nm = mio_pollfd(dev_mh, pfds + ns, POLLIN);
		else
			nm = 0;
		if (poll(pfds, ns + nm, -1) < 0) {
			if (errno == EINTR)
				continue;
			log_puts("poll failed\n");
			panic();
		}		
		if (dev_pstate == DEV_START) {
			ev = sio_revents(dev_sh, pfds);
			if (ev & POLLHUP) {
				log_puts(dev);
				log_puts(": audio device gone, stopping\n");
				break;
			}
			if (ev & (POLLIN | POLLOUT)) {
				if (!playrec_cycle() && dev_mh == NULL)
					break;
			}
		}
		if (dev_mh) {
			ev = mio_revents(dev_mh, pfds + ns);
			if (ev & POLLHUP) {
				log_puts(dev_port);
				log_puts(": midi port gone, stopping\n");
				break;
			}
			if (ev & POLLIN) {
				n = mio_read(dev_mh, mbuf, MIDIBUFSZ);
				midi_in(mbuf, n);
			}
		}
	}
	sigfillset(&sa.sa_mask);
	sa.sa_flags = SA_RESTART;
	sa.sa_handler = SIG_DFL;
	sigaction(SIGINT, &sa, NULL);
	sigaction(SIGTERM, &sa, NULL);
	sigaction(SIGHUP, &sa, NULL);

	if (dev_pstate == DEV_START)
		dev_mmcstop();
	xfree(pfds);
	dev_close();
	while (slot_list)
		slot_del(slot_list);
	return 1;
}

static int
opt_onoff(char *s, int *flag)
{
	if (strcmp("off", s) == 0) {
		*flag = 0;
		return 1;
	}
	if (strcmp("on", s) == 0) {
		*flag = 1;
		return 1;
	}
	log_puts(s);
	log_puts(": on/off expected\n");
	return 0;
}

static int
opt_enc(char *s, struct aparams *par)
{
	int len;

	len = aparams_strtoenc(par, s);
	if (len == 0 || s[len] != '\0') {
		log_puts(s);
		log_puts(": bad encoding\n");
		return 0;
	}
	return 1;
}

static int
opt_hdr(char *s, int *hdr)
{
	if (strcmp("auto", s) == 0) {
		*hdr = AFILE_HDR_AUTO;
		return 1;
	}
	if (strcmp("raw", s) == 0) {
		*hdr = AFILE_HDR_RAW;
		return 1;
	}
	if (strcmp("wav", s) == 0) {
		*hdr = AFILE_HDR_WAV;
		return 1;
	}
	if (strcmp("aiff", s) == 0) {
		*hdr = AFILE_HDR_AIFF;
		return 1;
	}
	if (strcmp("au", s) == 0) {
		*hdr = AFILE_HDR_AU;
		return 1;
	}
	log_puts(s);
	log_puts(": bad header type\n");
	return 0;
}

static int
opt_ch(char *s, int *rcmin, int *rcmax)
{
	char *next, *end;
	long cmin, cmax;

	errno = 0;
	cmin = strtol(s, &next, 10);
	if (next == s || *next != ':')
		goto failed;
	cmax = strtol(++next, &end, 10);
	if (end == next || *end != '\0')
		goto failed;
	if (cmin < 0 || cmax < cmin || cmax >= NCHAN_MAX)
		goto failed;
	*rcmin = cmin;
	*rcmax = cmax;
	return 1;
failed:
	log_puts(s);
	log_puts(": channel range expected\n");
	return 0;
}

static int
opt_num(char *s, int min, int max, int *num)
{
	const char *errstr;

	*num = strtonum(s, min, max, &errstr);
	if (errstr) {
		log_puts(s);
		log_puts(": expected integer between ");
		log_puti(min);
		log_puts(" and ");
		log_puti(max);
		log_puts("\n");
		return 0;
	}
	return 1;
}

int
main(int argc, char **argv)
{
	int dup, cmin, cmax, rate, vol, bufsz, hdr, mode;
	char *port, *dev;
	struct aparams par;
	int n_flag, c;

	vol = 127;
	dup = 0;
	bufsz = 0;
	rate = DEFAULT_RATE;
	cmin = 0;
	cmax = 1;
	aparams_init(&par);
	hdr = AFILE_HDR_AUTO;
	n_flag = 0;
	port = NULL;
	dev = NULL;
	mode = 0;
	
	while ((c = getopt(argc, argv, "b:c:de:f:h:i:j:no:q:r:t:v:")) != -1) {
		switch (c) {
		case 'b':
			if (!opt_num(optarg, 1, RATE_MAX, &bufsz))
				return 1;
			break;
		case 'c':
			if (!opt_ch(optarg, &cmin, &cmax))
				return 1;
			break;
		case 'd':
			log_level++;
			break;
		case 'e':
			if (!opt_enc(optarg, &par))
				return 1;
			break;
		case 'f':
			dev = optarg;
			break;
		case 'h':
			if (!opt_hdr(optarg, &hdr))
				return 1;
			break;
		case 'i':
			if (!slot_new(optarg, SIO_PLAY,
				&par, hdr, cmin, cmax, rate, dup, vol))
				return 1;
			mode |= SIO_PLAY;
			break;
		case 'j':
			if (!opt_onoff(optarg, &dup))
				return 1;
			break;
		case 'n':
			n_flag = 1;
			break;
		case 'o':
			if (!slot_new(optarg, SIO_REC,
				&par, hdr, cmin, cmax, rate, dup, 0))
				return 1;
			mode |= SIO_REC;
			break;
		case 'q':
			port = optarg;
			break;
		case 'r':
			if (!opt_num(optarg, RATE_MIN, RATE_MAX, &rate))
				return 1;
			break;
		case 'v':
			if (!opt_num(optarg, 0, MIDI_MAXCTL, &vol))
				return 1;
			break;
		default:
			goto bad_usage;
		}
	}
	argc -= optind;
	argv += optind;
	if (argc != 0) {
	bad_usage:
		log_puts(usagestr);
		return 1;
	}
	if (n_flag) {
		if (dev != NULL || port != NULL) {
			log_puts("-f and -q make no sense in off-line mode\n");
			return 1;
		}
		if (mode != (SIO_PLAY | SIO_REC)) {
			log_puts("both -i and -o required\n");
			return 0;
		}
		if (!offline())
			return 1;
	} else {
		if (dev == NULL)
			dev = SIO_DEVANY;
		if (mode == 0) {
			log_puts("at least of -i and -o required\n");
			return 1;
		} 
		if (!playrec(dev, mode, bufsz, port))
			return 1;
	}
	return 0;
}