/* osmo-cc-router 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 "call.h"
#include "audio.h"
#include "display.h"

int show_help = 0;
int num_kanal = 1;
static osmo_cc_endpoint_t *cc_ep1 = NULL, *cc_ep2 = NULL;

static char *routing_script = "~/.osmocom/router/routing.sh";
static char *routing_shell = "bash";
#define MAX_CC_ARGS 1024
static int cc_argc1 = 0, cc_argc2 = 0;
static const char *cc_argv1[MAX_CC_ARGS], *cc_argv2[MAX_CC_ARGS];

static void print_usage(const char *app)
{
	printf("Usage: %s [<options>]\n", app);
}

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");
	debug_print_help();
	printf(" -r --routing-script <script>\n");
	printf("        Define the script/executable that is executed to perform routing\n");
	printf("        decision for each call. (default = %s)\n", routing_script);
	printf(" -s --routing-shell <>\n");
	printf("        Define the shell to run the routing scrip. (default = %s)\n", routing_shell);
	printf(" -C --cc \"<osmo-cc arg>\" [--cc ...]\n");
	printf("        Pass arguments to Osmo-CC endpoint. Use '-cc help' for description.\n");
	printf(" --cc2 \"<osmo-cc arg>\" [--cc2 ...]\n");
	printf("        Pass arguments to Osmo-CC endpoint of second instance. (multistack).\n");
}

#define OPT_CC2	256


static void add_options(void)
{
	option_add('h', "help", 0);
	option_add('v', "verbose", 1);
	option_add('r', "routing-script", 1);
	option_add('s', "routing-shell", 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':
		show_help = 1;
		break;
	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 'r':
		routing_script = options_strdup(argv[argi]);
		break;
	case 's':
		routing_shell = options_strdup(argv[argi]);
		break;
	case 'C':
		if (!strcasecmp(argv[argi], "help")) {
			osmo_cc_help();
			return 0;
		}
		if (cc_argc1 == MAX_CC_ARGS) {
			fprintf(stderr, "Too many osmo-cc args!\n");
			break;
		}
		cc_argv1[cc_argc1++] = options_strdup(argv[argi]);
		break;
	case OPT_CC2:
		if (!strcasecmp(argv[argi], "help")) {
			osmo_cc_help();
			return 0;
		}
		if (cc_argc2 == MAX_CC_ARGS) {
			fprintf(stderr, "Too many osmo-cc args!\n");
			break;
		}
		cc_argv2[cc_argc2++] = 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[])
{
	double last_time_call = 0, now;
	int argi, rc;
	struct termios term, term_orig;
	int c;

	/* init FM */
	fm_init(0);

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

        /* handle options / config file */
	add_options();
	rc = options_config_file(argc, argv, "~/.osmocom/router/router.conf", handle_options);
	if (rc < 0)
		return 0;
	argi = options_command_line(argc, argv, handle_options);
	if (argi <= 0)
		return argi;
	if (show_help) {
		if (argi < argc) {
			routing_help(argv[argi]);
			return 0;
		}
		print_usage(argv[0]);
		print_help();
		printf("\n");
		env_help();
		printf("\n");
		routing_help(NULL);
		return 0;
	}

	/* init osmo-cc endpoint */
	cc_ep1 = calloc(1, sizeof(*cc_ep1));
	if (!cc_ep1)
		goto error;
	rc = osmo_cc_new(cc_ep1, OSMO_CC_VERSION, NULL, OSMO_CC_LOCATION_PRIV_SERV_LOC_USER, cc_message, NULL, NULL, cc_argc1, cc_argv1);
	if (rc < 0)
		goto error;
	if (cc_argc2) {
		/* init osmo-cc endpoint */
		cc_ep2 = calloc(1, sizeof(*cc_ep2));
		if (!cc_ep2)
			goto error;
		rc = osmo_cc_new(cc_ep2, OSMO_CC_VERSION, NULL, OSMO_CC_LOCATION_PRIV_SERV_LOC_USER, cc_message, NULL, NULL, cc_argc2, cc_argv2);
		if (rc < 0)
			goto error;
	}

	/* init call handling */
	call_init(cc_ep1, cc_ep2, routing_script, routing_shell);

	/* 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);

	printf("\nRouter is ready to process calls.\n\n");

	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 */
			call_clock(160);
		}

		process_timer();
		call_media_handle();
		do {
			w = 0;
			w |= osmo_cc_handle();
			w |= call_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:
	if (cc_ep1) {
		/* exit call handling */
		call_exit();

		/* exit osmo-cc endpoint */
		osmo_cc_delete(cc_ep1);
		free(cc_ep1);
	}
	if (cc_ep2) {
		/* exit call handling */
		call_exit();

		/* exit osmo-cc endpoint */
		osmo_cc_delete(cc_ep2);
		free(cc_ep2);
	}

	/* exit FM */
	fm_exit();

	options_free();

	return 0;
}