/* osmo-cc-ss5-endpoint main
 *
 * (C) 2020 by Andreas Eversberg <jolly@eversberg.eu>
 * All Rights Reserved
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <stdint.h>
#include <stdlib.h>
#include <termios.h>
#include "../libdebug/debug.h"
#include "../liboptions/options.h"
#include "../libg711/g711.h"
#include "ss5.h"
#include "display.h"

ss5_endpoint_t *ss5_ep_sunset = NULL, *ss5_ep_sunrise = NULL;
int num_kanal = 2;

int endpoints = 1;
int links = 0;
int prevent_blueboxing = 0;
int suppress_disconnect = 1;
int crosstalk = 1;
int delay_ms = 300;
int comfort_noise = 1;
double sense_db = 5;
#define MAX_CC_ARGS 1024
static int cc_argc_sunset, cc_argc_sunrise = 0;
static const char *cc_argv_sunset[MAX_CC_ARGS], *cc_argv_sunrise[MAX_CC_ARGS];

static void print_usage(const char *app)
{
	printf("Usage: %s [--port <misdn port>] [--nt] [<options>]\n", app);
	printf("This will create pairs of SS5 channels that are bridged together, so that\n");
	printf("calls from one link to the other can be made using SS5. The a bluebox can be\n");
	printf("used to play with it.\n");
	printf("If one endpoint is used (default), its name is 'sunset' and each pair of\n");
	printf("channels are bridged together. If two endpoints are used, their names are\n");
	printf("'sunset' and 'sunrise' and same channel index of both endpoints are bridged\n");
	printf("together.\n");
}

static void print_help()
{
	/*      -                                                                             - */
	printf(" -h --help\n");
	printf("        This help\n");
	printf(" --config [~/]<path to config file>\n");
	printf("        Give a config file to use. If it starts with '~/', path is at home dir.\n");
	printf("        Each line in config file is one option, '-' or '--' must not be given!\n");
	printf(" -v --verbose <level> | <level>,<category>[,<category>[,...]] | list\n");
	printf("        Use 'list' to get a list of all levels and categories\n");
	printf("        Verbose level: digit of debug level (default = '%d')\n", debuglevel);
	printf("        Verbose level+category: level digit followed by one or more categories\n");
	printf("        -> If no category is specified, all categories are selected\n");
	printf(" -2 --two\n");
	printf("        Create two Osmo-CC endpoints instead of one.\n");
	printf(" -c --channels\n");
	printf("        Give number of channels per endpoint. If you use a single endpoint,\n");
	printf("        you must define an even number. By default this is '2' for one\n");
	printf("        endpoint and '1' for two endpoints.\n");
	printf(" -s --suppress-disconnect 1 | 0\n");
	printf("        When a 'busy-flash' or 'release-guard' is received a disconnect is\n");
	printf("        forwarded towards OsmoCC. Set to 1 to suppress this. (Default is %d.)\n", suppress_disconnect);
	printf(" -p --prevent-blueboxing 1 | 0\n");
	printf("        Prevent blueboxing by making 'release-guard' 200 ms minimum length.\n");
	printf(" -x --crosstalk 1 | 0\n");
	printf("        Enable or disable some minor crosstalk. This allows you to hear\n");
	printf("        transmitted tones at a low volume. (Default is %d.).\n", crosstalk);
	printf(" -d --delay <ms> | 0\n");
	printf("        Add one-way delay to the connection between two SS5 links. This allows\n");
	printf("        to hear 'acknowlege' tones delayed. (Default is %d ms.).\n", delay_ms);
	printf(" -n --comfort-noise 1 | 0\n");
	printf("        Add comfort noise whenever there is no audio from the remote link\n");
	printf("        (before or after call). (Default is %d ms.).\n", comfort_noise);
	printf("    --sense 0 | <db>\n");
	printf("        Change sensitivity (level) of tone detector. A bluebox must not be\n");
	printf("        that loud. (Default is %.0f dB.).\n", sense_db);
	printf(" -C --cc \"<osmo-cc arg>\" [--cc ...]\n");
	printf("    --cc2 \"<osmo-cc arg>\" [--cc2 ...]\n");
	printf("        Pass arguments to Osmo-CC endpoint. Use '-cc help' for description.\n");
	printf("        If you select two endpoints, use '--cc2' to pass arguments to the\n");
	printf("        second endpoint.\n");
}

#define OPT_SENSE	256
#define OPT_CC2		257

static void add_options(void)
{
	option_add('h', "help", 0);
	option_add('v', "verbose", 1);
	option_add('2', "two", 0);
	option_add('c', "channels", 1);
	option_add('s', "suppress-disconnect", 1);
	option_add('p', "prevent-blueboxing", 1);
	option_add('x', "crosstalk", 1);
	option_add('d', "delay", 1);
	option_add('n', "comfort-noise", 1);
	option_add(OPT_SENSE, "sense", 1);
	option_add('C', "cc", 1);
	option_add(OPT_CC2, "cc2", 1);
}

static int handle_options(int short_option, int argi, char **argv)
{
	int rc;

	switch (short_option) {
	case 'h':
		print_usage(argv[0]);
		print_help();
		return 0;
	case 'v':
		if (!strcasecmp(argv[argi], "list")) {
			debug_list_cat();
			return 0;
		}
		rc = parse_debug_opt(argv[argi]);
		if (rc < 0) {
			fprintf(stderr, "Failed to parse debug option, please use -h for help.\n");
			return rc;
		}
		break;
	case '2':
		endpoints = 2;
		break;
	case 'c':
		links = atoi(argv[argi]);
		break;
	case 's':
		suppress_disconnect = atoi(argv[argi]);
		break;
	case 'p':
		prevent_blueboxing = atoi(argv[argi]);
		break;
	case 'x':
		crosstalk = atoi(argv[argi]);
		break;
	case 'd':
		delay_ms = atoi(argv[argi]);
		break;
	case 'n':
		comfort_noise = atoi(argv[argi]);
		break;
	case OPT_SENSE:
		sense_db = (double)atoi(argv[argi]);
		break;
	case 'C':
		if (!strcasecmp(argv[argi], "help")) {
			osmo_cc_help();
			return 0;
		}
		if (cc_argc_sunset == MAX_CC_ARGS) {
			fprintf(stderr, "Too many osmo-cc args!\n");
			break;
		}
		cc_argv_sunset[cc_argc_sunset++] = options_strdup(argv[argi]);
		break;
	case OPT_CC2:
		if (!strcasecmp(argv[argi], "help")) {
			osmo_cc_help();
			return 0;
		}
		if (cc_argc_sunrise == MAX_CC_ARGS) {
			fprintf(stderr, "Too many osmo-cc args!\n");
			break;
		}
		cc_argv_sunrise[cc_argc_sunrise++] = options_strdup(argv[argi]);
		break;
	default:
		return -EINVAL;
	}
	return 1;
}

static int quit = 0;
void sighandler(int sigset)
{
	if (sigset == SIGHUP || sigset == SIGPIPE)
		return;

	fprintf(stderr, "\nSignal %d received.\n", sigset);

	quit = 1;
}

static int get_char()
{
	struct timeval tv = {0, 0};
	fd_set fds;
	char c = 0;
	int __attribute__((__unused__)) rc;

	FD_ZERO(&fds);
	FD_SET(0, &fds);
	select(0+1, &fds, NULL, NULL, &tv);
	if (FD_ISSET(0, &fds)) {
		rc = read(0, &c, 1);
		return c;
	} else
		return -1;
}

int main(int argc, char *argv[])
{
	int argi, rc;
	struct termios term, term_orig;
	double now, last_time_call = 0.0;
	int c;

	/* init MF */
	mf_init(0);

	/* init codecs (for recording) */
	g711_init();

	cc_argv_sunset[cc_argc_sunset++] = options_strdup("remote auto");
	cc_argv_sunrise[cc_argc_sunrise++] = options_strdup("remote auto");

	/* handle options / config file */
	add_options();
	rc = options_config_file(argc, argv, "~/.osmocom/ss5/ss5.conf", handle_options);
	if (rc < 0)
		return 0;
	argi = options_command_line(argc, argv, handle_options);
	if (argi <= 0)
		return argi;

	/* check links (per endpoint) */
	if (!links)
		links = (endpoints == 2) ? 1 : 2;
	if (links == 1 && (endpoints % 1)) {
		PDEBUG(DSS5, DEBUG_ERROR, "You must define an even number of channels on a single endpoint!\n");
		goto error;
	}

	/* create sunset and (optionally) sunrise */
	ss5_ep_sunset = ss5_ep_create("sunset", links, prevent_blueboxing, crosstalk, delay_ms, comfort_noise, suppress_disconnect, sense_db);
	if (!ss5_ep_sunset)
		goto error;
	rc = osmo_cc_new(&ss5_ep_sunset->cc_ep, OSMO_CC_VERSION, "sunset", OSMO_CC_LOCATION_BEYOND_INTERWORKING, cc_message, NULL, ss5_ep_sunset, cc_argc_sunset, cc_argv_sunset);
	if (rc < 0)
		goto error;
	if (endpoints == 2) {
		ss5_ep_sunrise = ss5_ep_create("sunrise", links, prevent_blueboxing, crosstalk, delay_ms, comfort_noise, suppress_disconnect, sense_db);
		if (!ss5_ep_sunrise)
			goto error;
		rc = osmo_cc_new(&ss5_ep_sunrise->cc_ep, OSMO_CC_VERSION, "sunrise", OSMO_CC_LOCATION_BEYOND_INTERWORKING, cc_message, NULL, ss5_ep_sunrise, cc_argc_sunrise, cc_argv_sunrise);
		if (rc < 0)
			goto error;
		PDEBUG(DSS5, DEBUG_NOTICE, "Created endpoints 'sunset' and 'sunrise' with %d links that connect these endpoints.\n", links);
	} else
		PDEBUG(DSS5, DEBUG_NOTICE, "Created endpoint 'sunset' with %d links, each pair connected.\n", links);
	refresh_status();

	/* prepare terminal */
	tcgetattr(0, &term_orig);
	term = term_orig;
	term.c_lflag &= ~(ISIG|ICANON|ECHO);
	term.c_cc[VMIN]=1;
	term.c_cc[VTIME]=2;
	tcsetattr(0, TCSANOW, &term);

	/* catch signals */
	signal(SIGINT, sighandler);
	signal(SIGHUP, sighandler);
	signal(SIGTERM, sighandler);
	signal(SIGPIPE, sighandler);

	while (!quit) {
		int w;

		/* send clock calls to play/record audio files */
		now = get_time();
		if (now - last_time_call >= 0.1)
			last_time_call = now;
		if (now - last_time_call >= 0.020) {
			last_time_call += 0.020;
			/* call clock every 20ms */
			audio_clock(ss5_ep_sunset, ss5_ep_sunrise, 160);
		}

		process_timer();
		do {
			w = 0;
			w |= osmo_cc_handle();
		} while (w);
		usleep(1000);

		/* process keyboard input */
next_char:
		c = get_char();
		switch (c) {
		case 3:
			printf("CTRL+c received, quitting!\n");
			quit = 1;
			goto next_char;
		case 'c':
			display_status_on(-1);
			goto next_char;
		}
	}

	/* reset signals */
	signal(SIGINT, SIG_DFL);
	signal(SIGTSTP, SIG_DFL);
	signal(SIGHUP, SIG_DFL);
	signal(SIGTERM, SIG_DFL);
	signal(SIGPIPE, SIG_DFL);

	/* reset terminal */
	tcsetattr(0, TCSANOW, &term_orig);

error:
	/* destroy endpoints */
	if (ss5_ep_sunset) {
		osmo_cc_delete(&ss5_ep_sunset->cc_ep);
		ss5_ep_destroy(ss5_ep_sunset);
	}
	if (ss5_ep_sunrise) {
		osmo_cc_delete(&ss5_ep_sunrise->cc_ep);
		ss5_ep_destroy(ss5_ep_sunrise);
	}

	/* exit MF */
	mf_exit();

	options_free();

	return 0;
}