/*
 * Copyright (C) 2019 by Sukchan Lee <acetcom@gmail.com>
 *
 * This file is part of Open5GS.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero 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 <https://www.gnu.org/licenses/>.
 */

#include <signal.h>
#include <unistd.h>
#include <sys/stat.h>

#include "ogs-app.h"
#include "version.h"

static void show_version(void)
{
    printf("Open5GS %s\n\n", OPEN5GS_VERSION);
}

static void show_help(const char *name)
{
    printf("Usage: %s [options]\n"
        "Options:\n"
       "   -c filename    : set configuration file\n"
       "   -l filename    : set logging file\n"
       "   -e level       : set global log-level (default:info)\n"
       "   -m domain      : set log-domain (e.g. mme:sgw:gtp)\n"
       "   -d             : print lots of debugging information\n"
       "   -t             : print tracing information for developer\n"
       "   -D             : start as a daemon\n"
       "   -v             : show version number and exit\n"
       "   -h             : show this message and exit\n"
       "\n", name);
}

static int check_signal(int signum)
{
    switch (signum) {
    case SIGTERM:
    case SIGINT:
        ogs_info("%s received", 
                signum == SIGTERM ? "SIGTERM" : "SIGINT");

        return 1;
    case SIGHUP:
        ogs_info("SIGHUP received");
        ogs_log_cycle();

        break;
    case SIGWINCH:
        ogs_info("Signal-NUM[%d] received (%s)",
                signum, ogs_signal_description_get(signum));
        break;
    case SIGUSR1:
        fprintf(stderr,
                "%*s%-30s contains %6lu bytes in %3lu blocks (ref %d) %p\n",
                0, "", "core",
                (unsigned long)talloc_total_size(__ogs_talloc_core),
                (unsigned long)talloc_total_blocks(__ogs_talloc_core),
                (int)talloc_reference_count(__ogs_talloc_core),
                __ogs_talloc_core);
        break;

    case SIGUSR2:
        talloc_report_full(__ogs_talloc_core, stderr);
        break;

    default:
        ogs_error("Signal-NUM[%d] received (%s)",
                signum, ogs_signal_description_get(signum));
        break;
            
    }
    return 0;
}

static void terminate(void)
{
    app_terminate();

    ogs_app_terminate();
}

int main(int argc, const char *const argv[])
{
    /**************************************************************************
     * Starting up process.
     *
     * Keep the order of starting-up
     */
    int rv, i, opt;
    ogs_getopt_t options;
    struct {
        char *config_file;
        char *log_file;
        char *log_level;
        char *domain_mask;

        bool enable_debug;
        bool enable_trace;
    } optarg;
    const char *argv_out[argc+1];

    memset(&optarg, 0, sizeof(optarg));

    ogs_getopt_init(&options, (char**)argv);
    while ((opt = ogs_getopt(&options, "vhDc:l:e:m:dt")) != -1) {
        switch (opt) {
        case 'v':
            show_version();
            return OGS_OK;
        case 'h':
            show_help(argv[0]);
            return OGS_OK;
        case 'D':
#if !defined(_WIN32)
        {
            pid_t pid;
            pid = fork();

            ogs_assert(pid >= 0);

            if (pid != 0)
            {
                /* Parent */
                return EXIT_SUCCESS;
            }
            /* Child */

            setsid();
            umask(027);
        }
#else
            printf("%s: Not Support in WINDOWS", argv[0]);
#endif
            break;
        case 'c':
            optarg.config_file = options.optarg;
            break;
        case 'l':
            optarg.log_file = options.optarg;
            break;
        case 'e':
            optarg.log_level = options.optarg;
            break;
        case 'm':
            optarg.domain_mask = options.optarg;
            break;
        case 'd':
            optarg.enable_debug = true;
            break;
        case 't':
            optarg.enable_trace = true;
            break;
        case '?':
            fprintf(stderr, "%s: %s\n", argv[0], options.errmsg);
            show_help(argv[0]);
            return OGS_ERROR;
        default:
            fprintf(stderr, "%s: should not be reached\n", OGS_FUNC);
            return OGS_ERROR;
        }
    }

    if (optarg.enable_debug) optarg.log_level = (char*)"debug";
    if (optarg.enable_trace) optarg.log_level = (char*)"trace";

    i = 0;
    argv_out[i++] = argv[0];

    if (optarg.config_file) {
        argv_out[i++] = "-c";
        argv_out[i++] = optarg.config_file;
    }
    if (optarg.log_file) {
        argv_out[i++] = "-l";
        argv_out[i++] = optarg.log_file;
    }
    if (optarg.log_level) {
        argv_out[i++] = "-e";
        argv_out[i++] = optarg.log_level;
    }
    if (optarg.domain_mask) {
        argv_out[i++] = "-m";
        argv_out[i++] = optarg.domain_mask;
    }

    argv_out[i] = NULL;

    ogs_signal_init();
    ogs_setup_signal_thread();

    rv = ogs_app_initialize(OPEN5GS_VERSION, DEFAULT_CONFIG_FILENAME, argv_out);
    if (rv != OGS_OK) {
        if (rv == OGS_RETRY)
            return EXIT_SUCCESS;

        ogs_fatal("Open5GS initialization failed. Aborted");
        return OGS_ERROR;
    }

    rv = app_initialize(argv_out);
    if (rv != OGS_OK) {
        if (rv == OGS_RETRY)
            return EXIT_SUCCESS;

        ogs_fatal("Open5GS initialization failed. Aborted");
        return OGS_ERROR;
    }

    atexit(terminate);
    ogs_signal_thread(check_signal);

    ogs_info("Open5GS daemon terminating...");

    return OGS_OK;
}