/* osmo-cc-alsa-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 <sched.h>
#include "../libdebug/debug.h"
#include "../liboptions/options.h"
#include "../libg711/g711.h"
#include "telephone.h"

telephone_t *telephone_ep = NULL;
int num_kanal = 1;

static const char *name = "alsa";
static const char *audiodev = NULL;
static int samplerate = 48000;
static int latency = 50;
static int rt_prio = 1;
static const char *caller_id = "";
static int early_audio = 0;
static int autoalert = 0, autoanswer = 1;
#define MAX_CC_ARGS 1024
static int cc_argc = 0;
static const char *cc_argv[MAX_CC_ARGS];

static void print_usage(const char *app)
{
	printf("Usage: %s -a hw:<card>,<device> [<options>] [dialing]\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");
	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(" -n --name <interface name>\n");
	printf("        Give name of this interface. It will be sent in each call towards\n");
	printf(" -I --caller-id <caller id>\n");
	printf("        What caller ID to send on calls made from terminal. (default = '%s')\n", caller_id);
	printf(" -A --auto alerting | answer | off\n");
	printf("        An incoming call can be responded automatically with an alerting or an\n");
	printf("        answer, or not be responded automatically. (default = 'answer')\n");
	printf(" -E --early-audio\n");
	printf("        Send early audio when call is not yet connected. Must be used in\n");
	printf("        conjunction with --auto\n");
	printf(" -a --audio-device hw:<card>,<device>\n");
	printf("        Sound card and device number (default = '%s')\n", audiodev);
	printf(" -s --samplerate <rate>\n");
	printf("        Sample rate of sound device (default = '%d')\n", samplerate);
	printf(" -b --buffer <ms>\n");
	printf("        How many milliseconds are processed in advance (default = '%d')\n", latency);
	printf(" -r --realtime <prio>\n");
	printf("        Set prio: 0 to disable, 99 for maximum (default = %d)\n", rt_prio);
	printf(" -C --cc \"<osmo-cc arg>\" [--cc ...]\n");
	printf("        Pass arguments to Osmo-CC endpoint. Use '-cc help' for description.\n");
}

static void add_options(void)
{
	option_add('h', "help", 0);
	option_add('v', "verbose", 1);
	option_add('n', "name", 1);
	option_add('I', "caller-id", 1);
	option_add('A', "auto", 1);
	option_add('E', "early-audio", 0);
	option_add('a', "audio-device", 1);
	option_add('s', "samplerate", 1);
	option_add('b', "buffer", 1);
	option_add('r', "realtime", 1);
	option_add('C', "cc", 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 'n':
		name = options_strdup(argv[argi]);
		break;
	case 'I':
		caller_id = options_strdup(argv[argi]);
		break;
	case 'A':
		if (!strcasecmp(argv[argi], "alerting")) {
			autoalert = 1;
			autoanswer = 0;
		} else
		if (!strcasecmp(argv[argi], "answer")) {
			autoalert = 0;
			autoanswer = 1;
		} else
		if (!strcasecmp(argv[argi], "off")) {
			autoalert = 0;
			autoanswer = 0;
		} else {
			fprintf(stderr, "Unknown parameter '%s', please use -h for help.\n", argv[argi]);
			return -EINVAL;
		}
		break;
	case 'E':
		early_audio = 1;
		break;
	case 'a':
		audiodev = options_strdup(argv[argi]);
		break;
	case 's':
		samplerate = atoi(argv[argi]);
		break;
	case 'b':
		latency = atoi(argv[argi]);
		break;
	case 'r':
		rt_prio = atoi(argv[argi]);
		break;
	case 'C':
		if (!strcasecmp(argv[argi], "help")) {
			osmo_cc_help();
			return 0;
		}
		if (cc_argc == MAX_CC_ARGS) {
			fprintf(stderr, "Too many osmo-cc args!\n");
			break;
		}
		cc_argv[cc_argc++] = 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;
	const char *dialing = "";
	struct termios term, term_orig;
	char c;

	g711_init();

	telephone_ep = telephone_create();
	if (!telephone_ep)
		goto error;

	cc_argv[cc_argc++] = options_strdup("remote auto");

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

	if (argi < argc)
		dialing = argv[argi];

	rc = ui_init(dialing, autoalert, autoanswer);
	if (rc) {
		PDEBUG(DTEL, DEBUG_ERROR, "UI initializing failed!\n");
		goto error;
	}

	rc = telephone_init(telephone_ep, name, caller_id, OSMO_CC_LOCATION_USER, early_audio, audiodev, samplerate, samplerate * latency / 1000);
	if (rc) {
		PDEBUG(DTEL, DEBUG_ERROR, "Endpoint initializing failed!\n");
		goto error;
	}

	rc = osmo_cc_new(&telephone_ep->cc_ep, OSMO_CC_VERSION, name, OSMO_CC_LOCATION_USER, cc_message, NULL, telephone_ep, cc_argc, cc_argv);
	if (rc < 0)
		goto error;

	/* real time priority */
	if (rt_prio > 0) {
		struct sched_param schedp;
		int rc;

		memset(&schedp, 0, sizeof(schedp));
		schedp.sched_priority = rt_prio;
		rc = sched_setscheduler(0, SCHED_RR, &schedp);
		if (rc)
			fprintf(stderr, "Error setting SCHED_RR with prio %d\n", rt_prio);
	}

	/* 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);

	signal(SIGINT, sighandler);
	signal(SIGHUP, sighandler);
	signal(SIGTERM, sighandler);
	signal(SIGPIPE, sighandler);

	while (!quit) {
		int w;
		c = get_char();
		if (c == 3) {
			/* quit */
			if (clear_console_text)
			clear_console_text();
			printf("CTRL+c received, quitting!\n");
			quit = 1;
			continue;
		}
		process_timer();
		alsa_work(telephone_ep);
		rtp_work(telephone_ep);
		do {
			w = 0;
			w |= osmo_cc_handle();
			w |= ui_work(telephone_ep, c);
			c = 0;
		} while (w);
		usleep(1000);
	}

	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);
	
	/* reset real time prio */
	if (rt_prio > 0) {
		struct sched_param schedp;

		memset(&schedp, 0, sizeof(schedp));
		schedp.sched_priority = 0;
		sched_setscheduler(0, SCHED_OTHER, &schedp);
	}

error:
	if (telephone_ep) {
		osmo_cc_delete(&telephone_ep->cc_ep);
		telephone_destroy(telephone_ep);
	}

	options_free();

	return 0;
}