/*

 *  A simple PCM loopback utility

 *  Copyright (c) 2010 by Jaroslav Kysela <perex@perex.cz>

 *

 *     Author: Jaroslav Kysela <perex@perex.cz>

 *

 *

 *   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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 *

 */

#include <ctype.h>

#include <syslog.h>

#include <alsa/asoundlib.h>

#include "alsaloop.h"

static char *id_str(snd_ctl_elem_id_t *id)

{

	static char str[128];

	sprintf(str, "%i,%s,%i,%i,%s,%i",

		snd_ctl_elem_id_get_numid(id),

		snd_ctl_elem_iface_name(snd_ctl_elem_id_get_interface(id)),

		snd_ctl_elem_id_get_device(id),

		snd_ctl_elem_id_get_subdevice(id),

		snd_ctl_elem_id_get_name(id),

		snd_ctl_elem_id_get_index(id));

	return str;

}

int control_parse_id(const char *str, snd_ctl_elem_id_t *id)

{

	int c, size, numid;

	char *ptr;

	while (*str == ' ' || *str == '\t')

		str++;

	if (!(*str))

		return -EINVAL;

	snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_MIXER);	/* default */

	while (*str) {

		if (!strncasecmp(str, "numid=", 6)) {

			str += 6;

			numid = atoi(str);

			if (numid <= 0) {

				logit(LOG_CRIT, "Invalid numid %d\n", numid);

				return -EINVAL;

			}

			snd_ctl_elem_id_set_numid(id, atoi(str));

			while (isdigit(*str))

				str++;

		} else if (!strncasecmp(str, "iface=", 6)) {

			str += 6;

			if (!strncasecmp(str, "card", 4)) {

				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_CARD);

				str += 4;

			} else if (!strncasecmp(str, "mixer", 5)) {

				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_MIXER);

				str += 5;

			} else if (!strncasecmp(str, "pcm", 3)) {

				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_PCM);

				str += 3;

			} else if (!strncasecmp(str, "rawmidi", 7)) {

				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_RAWMIDI);

				str += 7;

			} else if (!strncasecmp(str, "timer", 5)) {

				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_TIMER);

				str += 5;

			} else if (!strncasecmp(str, "sequencer", 9)) {

				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_SEQUENCER);

				str += 9;

			} else {

				return -EINVAL;

			}

		} else if (!strncasecmp(str, "name=", 5)) {

			char buf[64];

			str += 5;

			ptr = buf;

			size = 0;

			if (*str == '\'' || *str == '\"') {

				c = *str++;

				while (*str && *str != c) {

					if (size < (int)sizeof(buf)) {

						*ptr++ = *str;

						size++;

					}

					str++;

				}

				if (*str == c)

					str++;

			} else {

				while (*str && *str != ',') {

					if (size < (int)sizeof(buf)) {

						*ptr++ = *str;

						size++;

					}

					str++;

				}

			}

			*ptr = '\0';

			snd_ctl_elem_id_set_name(id, buf);

		} else if (!strncasecmp(str, "index=", 6)) {

			str += 6;

			snd_ctl_elem_id_set_index(id, atoi(str));

			while (isdigit(*str))

				str++;

		} else if (!strncasecmp(str, "device=", 7)) {

			str += 7;

			snd_ctl_elem_id_set_device(id, atoi(str));

			while (isdigit(*str))

				str++;

		} else if (!strncasecmp(str, "subdevice=", 10)) {

			str += 10;

			snd_ctl_elem_id_set_subdevice(id, atoi(str));

			while (isdigit(*str))

				str++;

		}

		if (*str == ',') {

			str++;

		} else {

			if (*str)

				return -EINVAL;

		}

	}

	return 0;

}

int control_id_match(snd_ctl_elem_id_t *id1, snd_ctl_elem_id_t *id2)

{

	if (snd_ctl_elem_id_get_interface(id1) !=

	    snd_ctl_elem_id_get_interface(id2))

		return 0;

	if (snd_ctl_elem_id_get_device(id1) !=

	    snd_ctl_elem_id_get_device(id2))

		return 0;

	if (snd_ctl_elem_id_get_subdevice(id1) !=

	    snd_ctl_elem_id_get_subdevice(id2))

		return 0;

	if (strcmp(snd_ctl_elem_id_get_name(id1),

		   snd_ctl_elem_id_get_name(id2)) != 0)

		return 0;

	if (snd_ctl_elem_id_get_index(id1) !=

	    snd_ctl_elem_id_get_index(id2))

		return 0;

	return 1;

}

static int control_init1(struct loopback_handle *lhandle,

			 struct loopback_control *ctl)

{

	int err;

	snd_ctl_elem_info_set_id(ctl->info, ctl->id);

	snd_ctl_elem_value_set_id(ctl->value, ctl->id);

	if (lhandle->ctl == NULL) {

		logit(LOG_WARNING, "Unable to read control info for '%s'\n", id_str(ctl->id));

		return -EIO;

	}

	err = snd_ctl_elem_info(lhandle->ctl, ctl->info);

	if (err < 0) {

		logit(LOG_WARNING, "Unable to read control info '%s': %s\n", id_str(ctl->id), snd_strerror(err));

		return err;

	}

	err = snd_ctl_elem_read(lhandle->ctl, ctl->value);

	if (err < 0) {

		logit(LOG_WARNING, "Unable to read control value (init1) '%s': %s\n", id_str(ctl->id), snd_strerror(err));

		return err;

	}

	return 0;

}

static int copy_value(struct loopback_control *dst,

		      struct loopback_control *src)

{

	snd_ctl_elem_type_t type;

	unsigned int count;

	int i;

	type = snd_ctl_elem_info_get_type(dst->info);

	count = snd_ctl_elem_info_get_count(dst->info);

	switch (type) {

	case SND_CTL_ELEM_TYPE_BOOLEAN:

		for (i = 0; i < count; i++)

			snd_ctl_elem_value_set_boolean(dst->value,

				i, snd_ctl_elem_value_get_boolean(src->value, i));

		break;

	case SND_CTL_ELEM_TYPE_INTEGER:

		for (i = 0; i < count; i++) {

			snd_ctl_elem_value_set_integer(dst->value,

				i, snd_ctl_elem_value_get_integer(src->value, i));

		}

		break;

	default:

		logit(LOG_CRIT, "Unable to copy control value for type %s\n", snd_ctl_elem_type_name(type));

		return -EINVAL;

	}

	return 0;

}

static int oss_set(struct loopback *loop,

		   struct loopback_ossmixer *ossmix,

		   int enable)

{

	char buf[128], file[128];

	int fd;

	if (loop->capt->card_number < 0)

		return 0;

	if (!enable) {

		sprintf(buf, "%s \"\" 0\n", ossmix->oss_id);

	} else {

		sprintf(buf, "%s \"%s\" %i\n", ossmix->oss_id, ossmix->alsa_id, ossmix->alsa_index);

	}

	sprintf(file, "/proc/asound/card%i/oss_mixer", loop->capt->card_number);

	if (verbose)

		snd_output_printf(loop->output, "%s: Initialize OSS volume %s: %s", loop->id, file, buf);

	fd = open(file, O_WRONLY);

	if (fd >= 0 && write(fd, buf, strlen(buf)) == strlen(buf)) {

		close(fd);

		return 0;

	}

	if (fd >= 0)

		close(fd);

	logit(LOG_INFO, "%s: Unable to initialize OSS Mixer ID '%s'\n", loop->id, ossmix->oss_id);

	return -1;

}

static int control_init2(struct loopback *loop,

			 struct loopback_mixer *mix)

{

	snd_ctl_elem_type_t type;

	unsigned int count;

	int err;

	snd_ctl_elem_info_copy(mix->dst.info, mix->src.info);

	snd_ctl_elem_info_set_id(mix->dst.info, mix->dst.id);

	snd_ctl_elem_value_clear(mix->dst.value);

	snd_ctl_elem_value_set_id(mix->dst.value, mix->dst.id);

	type = snd_ctl_elem_info_get_type(mix->dst.info);

	count = snd_ctl_elem_info_get_count(mix->dst.info);

	snd_ctl_elem_remove(loop->capt->ctl, mix->dst.id);

	switch (type) {

	case SND_CTL_ELEM_TYPE_BOOLEAN:

		err = snd_ctl_elem_add_boolean(loop->capt->ctl,

					       mix->dst.id, count);

		copy_value(&mix->dst, &mix->src);

		break;

	case SND_CTL_ELEM_TYPE_INTEGER:

		err = snd_ctl_elem_add_integer(loop->capt->ctl,

				mix->dst.id, count,

				snd_ctl_elem_info_get_min(mix->dst.info),

				snd_ctl_elem_info_get_max(mix->dst.info),

				snd_ctl_elem_info_get_step(mix->dst.info));

		copy_value(&mix->dst, &mix->src);

		break;

	default:

		logit(LOG_CRIT, "Unable to handle control type %s\n", snd_ctl_elem_type_name(type));

		err = -EINVAL;

		break;

	}

	if (err < 0) {

		logit(LOG_CRIT, "Unable to create control '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));

		return err;

	}

	err = snd_ctl_elem_unlock(loop->capt->ctl, mix->dst.id);

	if (err < 0) {

		logit(LOG_CRIT, "Unable to unlock control info '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));

		return err;

	}

	err = snd_ctl_elem_info(loop->capt->ctl, mix->dst.info);

	if (err < 0) {

		logit(LOG_CRIT, "Unable to read control info '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));

		return err;

	}

	if (snd_ctl_elem_info_is_tlv_writable(mix->dst.info)) {

		unsigned int tlv[64];

		err = snd_ctl_elem_tlv_read(loop->play->ctl,

					    mix->src.id,

					    tlv, sizeof(tlv));

		if (err < 0) {

			logit(LOG_CRIT, "Unable to read TLV for '%s': %s\n", id_str(mix->src.id), snd_strerror(err));

			tlv[0] = tlv[1] = 0;

		}

		err = snd_ctl_elem_tlv_write(loop->capt->ctl,

					     mix->dst.id,

					     tlv);

		if (err < 0) {

			logit(LOG_CRIT, "Unable to write TLV for '%s': %s\n", id_str(mix->src.id), snd_strerror(err));

			return err;

		}

	}

	err = snd_ctl_elem_write(loop->capt->ctl, mix->dst.value);

	if (err < 0) {

		logit(LOG_CRIT, "Unable to write control value '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));

		return err;

	}

	return 0;

}

int control_init(struct loopback *loop)

{

	struct loopback_mixer *mix;

	struct loopback_ossmixer *ossmix;

	int err;

	for (ossmix = loop->oss_controls; ossmix; ossmix = ossmix->next)

		oss_set(loop, ossmix, 0);

	for (mix = loop->controls; mix; mix = mix->next) {

		err = control_init1(loop->play, &mix->src);

		if (err < 0) {

			logit(LOG_WARNING, "%s: Disabling playback control '%s'\n", loop->id, id_str(mix->src.id));

			mix->skip = 1;

			continue;

		}

		err = control_init2(loop, mix);

		if (err < 0)

			return err;

	}

	for (ossmix = loop->oss_controls; ossmix; ossmix = ossmix->next) {

		err = oss_set(loop, ossmix, 1);

		if (err < 0) {

			ossmix->skip = 1;

			logit(LOG_WARNING, "%s: Disabling OSS mixer ID '%s'\n", loop->id, ossmix->oss_id);

		}

	}

	return 0;

}

int control_done(struct loopback *loop)

{

	struct loopback_mixer *mix;

	struct loopback_ossmixer *ossmix;

	int err;

	if (loop->capt->ctl == NULL)

		return 0;

	for (ossmix = loop->oss_controls; ossmix; ossmix = ossmix->next) {

		err = oss_set(loop, ossmix, 0);

		if (err < 0)

			logit(LOG_WARNING, "%s: Unable to remove OSS control '%s'\n", loop->id, ossmix->oss_id);

	}

	for (mix = loop->controls; mix; mix = mix->next) {

		if (mix->skip)

			continue;

		err = snd_ctl_elem_remove(loop->capt->ctl, mix->dst.id);

		if (err < 0)

			logit(LOG_WARNING, "%s: Unable to remove control '%s': %s\n", loop->id, id_str(mix->dst.id), snd_strerror(err));

	}

	return 0;

}

static int control_event1(struct loopback *loop,

			  struct loopback_mixer *mix,

			  snd_ctl_event_t *ev,

			  int capture)

{

	unsigned int mask = snd_ctl_event_elem_get_mask(ev);

	int err;

	if (mask == SND_CTL_EVENT_MASK_REMOVE)

		return 0;

	if ((mask & SND_CTL_EVENT_MASK_VALUE) == 0)

		return 0;

	if (!capture) {

		snd_ctl_elem_value_set_id(mix->src.value, mix->src.id);

		err = snd_ctl_elem_read(loop->play->ctl, mix->src.value);

		if (err < 0) {

			logit(LOG_CRIT, "Unable to read control value (event1) '%s': %s\n", id_str(mix->src.id), snd_strerror(err));

			return err;

		}

		copy_value(&mix->dst, &mix->src);

		err = snd_ctl_elem_write(loop->capt->ctl, mix->dst.value);

		if (err < 0) {

			logit(LOG_CRIT, "Unable to write control value (event1) '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));

			return err;

		}

	} else {

		err = snd_ctl_elem_read(loop->capt->ctl, mix->dst.value);

		if (err < 0) {

			logit(LOG_CRIT, "Unable to read control value (event2) '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));

			return err;

		}

		copy_value(&mix->src, &mix->dst);

		err = snd_ctl_elem_write(loop->play->ctl, mix->src.value);

		if (err < 0) {

			logit(LOG_CRIT, "Unable to write control value (event2) '%s': %s\n", id_str(mix->src.id), snd_strerror(err));

			return err;

		}

	}

	return 0;

}

int control_event(struct loopback_handle *lhandle, snd_ctl_event_t *ev)

{

	snd_ctl_elem_id_t *id2;

	struct loopback_mixer *mix;

	int capt = lhandle == lhandle->loopback->capt;

	int err;

	snd_ctl_elem_id_alloca(&id2);

	snd_ctl_event_elem_get_id(ev, id2);

	for (mix = lhandle->loopback->controls; mix; mix = mix->next) {

		if (mix->skip)

			continue;

		if (control_id_match(id2, capt ? mix->dst.id : mix->src.id)) {

			err = control_event1(lhandle->loopback, mix, ev, capt);

			if (err < 0)

				return err;

		}

	}

	return 0;

}