/*********************************************************************************************************
* Software License Agreement (BSD License)                                                               *
* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
*													 *
* Copyright (c) 2015, WIDE Project and NICT								 *
* All rights reserved.											 *
* 													 *
* Redistribution and use of this software in source and binary forms, with or without modification, are  *
* permitted provided that the following conditions are met:						 *
* 													 *
* * Redistributions of source code must retain the above 						 *
*   copyright notice, this list of conditions and the 							 *
*   following disclaimer.										 *
*    													 *
* * Redistributions in binary form must reproduce the above 						 *
*   copyright notice, this list of conditions and the 							 *
*   following disclaimer in the documentation and/or other						 *
*   materials provided with the distribution.								 *
* 													 *
* * Neither the name of the WIDE Project or NICT nor the 						 *
*   names of its contributors may be used to endorse or 						 *
*   promote products derived from this software without 						 *
*   specific prior written permission of WIDE Project and 						 *
*   NICT.												 *
* 													 *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 	 *
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF   *
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.								 *
*********************************************************************************************************/

#include <freeDiameter/freeDiameter-host.h>
#include <freeDiameter/libfdcore.h>

#include <signal.h>
#include <getopt.h>
#include <locale.h>


/* forward declarations */
static int main_cmdline(int argc, char *argv[]);
static void * catch_signals(void * arg);
static pthread_t signals_thr;

static char *conffile = NULL;
static int gnutls_debug = 0;

/* gnutls debug */
static void fd_gnutls_debug(int level, const char * str) {
	fd_log_debug(" [gnutls:%d] %s", level, str);
}


/* freeDiameter starting point */
int main(int argc, char * argv[])
{
	int ret;
	sigset_t sig_all;
	
	/* Block all signals from the current thread and all its future children -- we will catch everything in catch_signals */
	sigfillset(&sig_all);
	ret = pthread_sigmask(SIG_BLOCK, &sig_all, NULL);
	ASSERT(ret == 0);
	
	/* Parse the command-line */
	ret = main_cmdline(argc, argv);
	if (ret != 0) {
		return ret;
	}
	
	/* Initialize the core library */
	ret = fd_core_initialize();
	if (ret != 0) {
		fprintf(stderr, "An error occurred during freeDiameter core library initialization.\n");
		return ret;
	}
	
	/* Set gnutls debug level ? */
	if (gnutls_debug) {
		gnutls_global_set_log_function((gnutls_log_func)fd_gnutls_debug);
		gnutls_global_set_log_level (gnutls_debug);
		TRACE_DEBUG(INFO, "Enabled GNUTLS debug at level %d", gnutls_debug);
	}
	
	/* Parse the configuration file */
	CHECK_FCT_DO( fd_core_parseconf(conffile), goto error );
	
	/* Start the servers */
	CHECK_FCT_DO( fd_core_start(), goto error );
	
	/* Allow SIGINT and SIGTERM from this point to terminate the application */
	CHECK_POSIX_DO( pthread_create(&signals_thr, NULL, catch_signals, NULL), goto error );
	
	TRACE_DEBUG(INFO, FD_PROJECT_BINARY " daemon initialized.");

	/* Now, just wait for termination */
	CHECK_FCT( fd_core_wait_shutdown_complete() );
	
	/* Just in case it was not the result of a signal, we cancel signals_thr */
	fd_thr_term(&signals_thr);
	
	return 0;
error:	
	CHECK_FCT_DO( fd_core_shutdown(),  );
	CHECK_FCT( fd_core_wait_shutdown_complete() );
	fd_thr_term(&signals_thr);
	return -1;
}


/* Display package version */
static void main_version_core(void)
{
	printf("%s, version %s\n", FD_PROJECT_NAME, fd_core_version);
}

/* Display package version and general info */
static void main_version(void)
{
	main_version_core();
	printf( "%s\n", FD_PROJECT_COPYRIGHT);
	printf( "\nSee " FD_PROJECT_NAME " homepage at http://www.freediameter.net/\n"
		" for information, updates and bug reports on this software.\n");
}

/* Print command-line options */
static void main_help( void )
{
	main_version_core();
	printf(	"  This daemon is an implementation of the Diameter protocol\n"
		"  used for Authentication, Authorization, and Accounting (AAA).\n");
	printf("\nUsage:  " FD_PROJECT_BINARY " [OPTIONS]...\n");
	printf( "  -h, --help             Print help and exit\n"
  		"  -V, --version          Print version and exit\n"
  		"  -c, --config=filename  Read configuration from this file instead of the \n"
		"                           default location (" DEFAULT_CONF_PATH "/" FD_DEFAULT_CONF_FILENAME ").\n");
 	printf( "\nDebug:\n"
  		"  These options are mostly useful for developers\n"
  		"  -l, --dbglocale         Set the locale for error messages\n"
  		"  -d, --debug             Increase verbosity of debug messages if default logger is used\n"
  		"  -q, --quiet             Decrease verbosity if default logger is used\n"
  		"  -f, --dbg_func <func>   Enable all traces within the function <func>\n"
  		"  -F, --dbg_file <file.c> Enable all traces within the file <file.c> (basename match)\n"
  		"  --dbg_gnutls <int>      Enable GNU TLS debug at level <int>\n"
	);
}

/* Parse the command-line */
static int main_cmdline(int argc, char *argv[])
{
	int c;
	int option_index = 0;
	char * locale;
	
      	struct option long_options[] = {
		{ "help",	no_argument, 		NULL, 'h' },
		{ "version",	no_argument, 		NULL, 'V' },
		{ "config",	required_argument, 	NULL, 'c' },
		{ "debug",	no_argument, 		NULL, 'd' },
		{ "quiet",	no_argument, 		NULL, 'q' },
		{ "dbglocale",	optional_argument, 	NULL, 'l' },
		{ "dbg_func",	required_argument, 	NULL, 'f' },
		{ "dbg_file",	required_argument, 	NULL, 'F' },
		{ "dbg_gnutls",	required_argument, 	NULL, 'g' },
		{ NULL,		0, 			NULL, 0 }
	};
	
	/* Loop on arguments */
	while (1) {
		c = getopt_long (argc, argv, "hVc:dql:f:F:g:", long_options, &option_index);
		if (c == -1) 
			break;	/* Exit from the loop.  */
		
		switch (c) {
			case 'h':	/* Print help and exit.  */
				main_help();
				exit(0);

			case 'V':	/* Print version and exit.  */
				main_version();
				exit(0);

			case 'c':	/* Read configuration from this file instead of the default location..  */
				if (optarg == NULL ) {
					fprintf(stderr, "Missing argument with --config directive\n");
					return EINVAL;
				}
				conffile = optarg;
				break;

			case 'l':	/* Change the locale.  */
				locale = setlocale(LC_ALL, optarg?:"");
				if (!locale) {
					fprintf(stderr, "Unable to set locale (%s)\n", optarg);
					return EINVAL;
				}
				break;
				
			case 'd':	/* Increase verbosity of debug messages.  */
				fd_g_debug_lvl--;
				break;
				
			case 'f':	/* Full debug for the function with this name.  */
				#ifdef DEBUG
				fd_debug_one_function = optarg;
				fd_g_debug_lvl = FD_LOG_DEBUG;
				#else /* DEBUG */
				fprintf(stderr, "Error: must compile with DEBUG support to use --dbg_func feature!\n");
				return EINVAL;
				#endif /* DEBUG */
				break;
				
			case 'F':	/* Full debug for the file with this name.  */
				#ifdef DEBUG
				fd_debug_one_file = basename(optarg);
				fd_g_debug_lvl = FD_LOG_DEBUG;
				#else /* DEBUG */
				fprintf(stderr, "Error: must compile with DEBUG support to use --dbg_file feature!\n");
				return EINVAL;
				#endif /* DEBUG */
				break;
				
			case 'g':	/* Set a debug level and function for GNU TLS calls.  */
				gnutls_debug = (int)atoi(optarg);
				break;
				
			case 'q':	/* Decrease verbosity then remove debug messages.  */
				fd_g_debug_lvl++;
				break;

			case '?':	/* Invalid option.  */
				/* `getopt_long' already printed an error message.  */
				fprintf(stderr, "getopt_long found an invalid character\n");
				return EINVAL;

			default:	/* bug: option not considered.  */
				fprintf(stderr, "A command-line option is missing in parser: %c\n", c);
				ASSERT(0);
				return EINVAL;
		}
	}
		
	return 0;
}

/* Handle some signals */
static void * catch_signals(void * arg)
{
	sigset_t ss;
	fd_log_threadname ( "signals catcher" );
	
	sigemptyset(&ss);
	
	/* Signals that terminate the daemon */
	sigaddset(&ss, SIGTERM);
	sigaddset(&ss, SIGINT);
	
	/* Signals that send an event */
	sigaddset(&ss, SIGUSR1);
	sigaddset(&ss, SIGUSR2);
	
	/* We unblock all other signals, so that their default handler is used (such as SIGTSTP) */
	CHECK_SYS_DO( pthread_sigmask( SIG_SETMASK, &ss, NULL ), goto out );
	
	/* Now loop on the reception of the signal */
	while (1) {
		int sig, *ps;
		
		/* Wait to receive the next signal */
		CHECK_POSIX_DO( sigwait(&ss, &sig), break );
		
		TRACE_DEBUG(FULL, "Signal %d caught", sig);
		
		switch (sig) {
			case SIGUSR1:
			case SIGUSR2:
				CHECK_MALLOC_DO( ps = malloc(sizeof(int)), goto out);
				*ps = sig;
				CHECK_FCT_DO( fd_event_send(fd_g_config->cnf_main_ev, FDEV_TRIGGER, sizeof(int), ps), goto out );
				break;
				
			case SIGINT:
			case SIGTERM:
				CHECK_FCT_DO( fd_core_shutdown(), goto out );

		}
	}
out:	
	/* Better way to handle this ? */
	ASSERT(0);
	return NULL;
}