/*

 * Copyright (C) 2019-2023 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 "ogs-app.h"

int __ogs_app_domain;

static int read_config(void);

static int parse_config(void);

int ogs_app_initialize(

        const char *version, const char *default_config,

        const char *const argv[])

{

    int rv, opt;

    ogs_getopt_t options;

    struct {

        char *config_file;

        char *log_file;

        char *log_level;

        char *domain_mask;

        char *config_section_id;

    } optarg;

    ogs_core_initialize();

    ogs_app_setup_log();

    ogs_app_context_init();

    ogs_app_config_init();

    ogs_app()->version = version;

    /**************************************************************************

     * Stage 1 : Command Line Options

     */

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

    ogs_getopt_init(&options, (char**)argv);

    while ((opt = ogs_getopt(&options, "c:l:e:m:k:")) != -1) {

        switch (opt) {

        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 'k':

            optarg.config_section_id = options.optarg;

            break;

        case '?':

        default:

            ogs_assert_if_reached();

            return OGS_ERROR;

        }

    }

    /**************************************************************************

     * Stage 2 : Load Configuration File

     */

    if (optarg.config_file)

        ogs_app()->file = optarg.config_file;

    else

        ogs_app()->file = default_config;

    rv = read_config();

    if (rv != OGS_OK) return rv;

    rv = parse_config();

    if (rv != OGS_OK) return rv;

    /**************************************************************************

     * Stage 3 : Initialize Default Memory Pool

     */

    ogs_pkbuf_default_create(&ogs_global_conf()->pkbuf_config);

    /**************************************************************************

     * Stage 4 : Setup LOG Module

     */

    if (optarg.log_file)

        ogs_app()->logger.file = optarg.log_file;

    if (ogs_app()->logger.file) {

        if (ogs_log_add_file(ogs_app()->logger.file) == NULL) {

            ogs_fatal("cannot open log file : %s", 

                    ogs_app()->logger.file);

            return OGS_ERROR;

        }

    }

    if (optarg.domain_mask)

        ogs_app()->logger.domain = optarg.domain_mask;

    if (optarg.log_level) 

        ogs_app()->logger.level = optarg.log_level;

    rv = ogs_log_config_domain(

            ogs_app()->logger.domain, ogs_app()->logger.level);

    if (rv != OGS_OK) return rv;

    ogs_log_set_timestamp(ogs_app()->logger_default.timestamp,

                          ogs_app()->logger.timestamp);

    /**************************************************************************

     * Stage 5 : Setup Database Module

     */

    if (ogs_env_get("DB_URI"))

        ogs_app()->db_uri = ogs_env_get("DB_URI");

    /**************************************************************************

     * Stage 6 : Setup configuration section ID for running multiple NF from

     * same config file

     */

    if (optarg.config_section_id)

        ogs_app()->config_section_id = atoi(optarg.config_section_id);

    /**************************************************************************

     * Stage 7 : Print Banner

     */

    if (ogs_app()->version) {

        ogs_log_print(OGS_LOG_INFO,

                "Open5GS daemon %s\n\n", ogs_app()->version);

        ogs_info("Configuration: '%s'", ogs_app()->file);

        if (ogs_app()->logger.file) {

            ogs_info("File Logging: '%s'", ogs_app()->logger.file);

            if (ogs_app()->logger.level)

                ogs_info("LOG-LEVEL: '%s'", ogs_app()->logger.level);

            if (ogs_app()->logger.domain)

                ogs_info("LOG-DOMAIN: '%s'", ogs_app()->logger.domain);

        }

    }

    /**************************************************************************

     * Stage 8 : Queue, Timer and Poll

     */

    ogs_app()->queue = ogs_queue_create(ogs_app()->pool.event);

    ogs_assert(ogs_app()->queue);

    ogs_app()->timer_mgr = ogs_timer_mgr_create(ogs_app()->pool.timer);

    ogs_assert(ogs_app()->timer_mgr);

    ogs_app()->pollset = ogs_pollset_create(ogs_app()->pool.socket);

    ogs_assert(ogs_app()->pollset);

    return rv;

}

void ogs_app_terminate(void)

{

    ogs_app_config_final();

    ogs_app_context_final();

    ogs_pkbuf_default_destroy();

    ogs_core_terminate();

}

static int read_config(void)

{

    FILE *file;

    yaml_parser_t parser;

    yaml_document_t *document = NULL;

    ogs_assert(ogs_app()->file);

    file = fopen(ogs_app()->file, "rb");

    if (!file) {

        ogs_fatal("cannot open file `%s`", ogs_app()->file);

        return OGS_ERROR;

    }

    ogs_assert(yaml_parser_initialize(&parser));

    yaml_parser_set_input_file(&parser, file);

    document = calloc(1, sizeof(yaml_document_t));

    if (!yaml_parser_load(&parser, document)) {

        ogs_fatal("Failed to parse configuration file '%s'", ogs_app()->file);

        switch (parser.error) {

        case YAML_MEMORY_ERROR:

            ogs_error("Memory error: Not enough memory for parsing");

            break;

        case YAML_READER_ERROR:

            if (parser.problem_value != -1)

                ogs_error("Reader error - %s: #%X at %zd", parser.problem,

                    parser.problem_value, parser.problem_offset);

            else

                ogs_error("Reader error - %s at %zd", parser.problem,

                    parser.problem_offset);

            break;

        case YAML_SCANNER_ERROR:

            if (parser.context)

                ogs_error("Scanner error - %s at line %zu, column %zu "

                        "%s at line %zu, column %zu", parser.context,

                        parser.context_mark.line+1,

                        parser.context_mark.column+1,

                        parser.problem, parser.problem_mark.line+1,

                        parser.problem_mark.column+1);

            else

                ogs_error("Scanner error - %s at line %zu, column %zu",

                        parser.problem, parser.problem_mark.line+1,

                        parser.problem_mark.column+1);

            break;

        case YAML_PARSER_ERROR:

            if (parser.context)

                ogs_error("Parser error - %s at line %zu, column %zu "

                        "%s at line %zu, column %zu", parser.context,

                        parser.context_mark.line+1,

                        parser.context_mark.column+1,

                        parser.problem, parser.problem_mark.line+1,

                        parser.problem_mark.column+1);

            else

                ogs_error("Parser error - %s at line %zu, column %zu",

                        parser.problem, parser.problem_mark.line+1,

                        parser.problem_mark.column+1);

            break;

        default:

            /* Couldn't happen. */

            ogs_assert_if_reached();

            break;

        }

        free(document);

        yaml_parser_delete(&parser);

        ogs_assert(!fclose(file));

        return OGS_ERROR;

    }

    ogs_app()->document = document;

    yaml_parser_delete(&parser);

    ogs_assert(!fclose(file));

    return OGS_OK;

}

static int context_prepare(void)

{

    int rv;

#define USRSCTP_LOCAL_UDP_PORT      9899

    ogs_app()->usrsctp.udp_port = USRSCTP_LOCAL_UDP_PORT;

    rv = ogs_app_global_conf_prepare();

    if (rv != OGS_OK) return rv;

    return OGS_OK;

}

static int context_validation(void)

{

    return OGS_OK;

}

static void parse_config_logger_file(ogs_yaml_iter_t *logger_iter,

                                     const char *logger_key)

{

    ogs_yaml_iter_t iter;

    /* Legacy format:

     *   logger:

     *     file: /var/log/open5gs/mme.log */

    if (!strcmp(logger_key, "file") && ogs_yaml_iter_has_value(logger_iter)) {

        ogs_app()->logger.file = ogs_yaml_iter_value(logger_iter);

        ogs_warn("Please change the configuration file as below.");

        ogs_log_print(OGS_LOG_WARN, "\n<OLD Format>\n");

        ogs_log_print(OGS_LOG_WARN, "logger:\n");

        ogs_log_print(OGS_LOG_WARN, "  file: %s\n", ogs_app()->logger.file);

        ogs_log_print(OGS_LOG_WARN, "\n<NEW Format>\n");

        ogs_log_print(OGS_LOG_WARN, "logger:\n");

        ogs_log_print(OGS_LOG_WARN, "  file:\n");

        ogs_log_print(OGS_LOG_WARN, "    path: %s\n", ogs_app()->logger.file);

        ogs_log_print(OGS_LOG_WARN, "\n\n\n");

        return;

    }

    /* Current format:

     *   logger:

     *     default:

     *       timestamp: false

     *     file:

     *       path: /var/log/open5gs/mme.log

     *       timestamp: true */

    ogs_yaml_iter_recurse(logger_iter, &iter);

    while (ogs_yaml_iter_next(&iter)) {

        const char *key = ogs_yaml_iter_key(&iter);

        ogs_assert(key);

        if (!strcmp(key, "timestamp")) {

            ogs_log_ts_e ts = ogs_yaml_iter_bool(&iter)

                              ? OGS_LOG_TS_ENABLED

                              : OGS_LOG_TS_DISABLED;

            if (!strcmp(logger_key, "default")) {

                ogs_app()->logger_default.timestamp = ts;

            } else if (!strcmp(logger_key, "file")) {

                ogs_app()->logger.timestamp = ts;

            }

        } else if (!strcmp(key, "path")) {

            if (!strcmp(logger_key, "file")) {

                ogs_app()->logger.file = ogs_yaml_iter_value(&iter);

            }

        }

    }

}

static int parse_config(void)

{

    int rv;

    yaml_document_t *document = NULL;

    ogs_yaml_iter_t root_iter;

    document = ogs_app()->document;

    ogs_assert(document);

    rv = context_prepare();

    if (rv != OGS_OK) return rv;

    ogs_yaml_iter_init(&root_iter, document);

    while (ogs_yaml_iter_next(&root_iter)) {

        const char *root_key = ogs_yaml_iter_key(&root_iter);

        ogs_assert(root_key);

        if (!strcmp(root_key, "db_uri")) {

            ogs_app()->db_uri = ogs_yaml_iter_value(&root_iter);

        } else if (!strcmp(root_key, "logger")) {

            ogs_yaml_iter_t logger_iter;

            ogs_yaml_iter_recurse(&root_iter, &logger_iter);

            while (ogs_yaml_iter_next(&logger_iter)) {

                const char *logger_key = ogs_yaml_iter_key(&logger_iter);

                ogs_assert(logger_key);

                parse_config_logger_file(&logger_iter, logger_key);

                if (!strcmp(logger_key, "level")) {

                    ogs_app()->logger.level =

                        ogs_yaml_iter_value(&logger_iter);

                } else if (!strcmp(logger_key, "domain")) {

                    ogs_app()->logger.domain =

                        ogs_yaml_iter_value(&logger_iter);

                }

            }

        } else if (!strcmp(root_key, "global")) {

            rv = ogs_app_parse_global_conf(&root_iter);

            if (rv != OGS_OK) {

                ogs_error("ogs_global_conf_parse_config() failed");

                return rv;

            }

        } else {

            rv = ogs_app_count_nf_conf_sections(root_key);

            if (rv != OGS_OK) {

                ogs_error("ogs_app_count_nf_conf_sections() failed");

                return rv;

            }

        }

    }

    rv = context_validation();

    if (rv != OGS_OK) return rv;

    return OGS_OK;

}

void ogs_app_setup_log(void)

{

    ogs_log_install_domain(&__ogs_app_domain, "app", ogs_core()->log.level);

}