/** Configuration parser.
 *
 * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
 * @copyright 2017, Institute for Automation of Complex Power Systems, EONERC
 *********************************************************************************/

#include <stdlib.h>
#include <string.h>
#include <libgen.h>
#include <unistd.h>

#include "utils.h"
#include "list.h"
#include "cfg.h"
#include "node.h"
#include "path.h"
#include "hook.h"
#include "advio.h"
#include "web.h"
#include "log.h"
#include "api.h"
#include "plugin.h"
#include "node.h"

#include "kernel/rt.h"

int cfg_init_pre(struct cfg *cfg)
{
	config_init(&cfg->cfg);
	
	info("Inititliaze logging sub-system");
	log_init(&cfg->log, V, LOG_ALL);

	list_init(&cfg->nodes);
	list_init(&cfg->paths);
	list_init(&cfg->plugins);

	return 0;
}

int cfg_init_post(struct cfg *cfg)
{
	info("Initialize memory system");
	memory_init();

	rt_init(cfg->priority, cfg->affinity);
	api_init(&cfg->api, cfg);
	web_init(&cfg->web, &cfg->api);
	
	info("Initialize node types");
	list_foreach(struct node *n, &cfg->nodes) { INDENT
		config_setting_t *cfg_root = config_root_setting(&cfg->cfg);
		
		node_type_init(n->_vt, cfg->cli.argc, cfg->cli.argv, cfg_root);
	}
	
	return 0;
}

int cfg_deinit(struct cfg *cfg)
{
	info("De-initializing node types");
	list_foreach(struct plugin *p, &plugins) { INDENT
		if (p->type == PLUGIN_TYPE_NODE)
			node_type_deinit(&p->node);
	}
	
	info("De-initializing web interface");
	web_deinit(&cfg->web);
	
	info("De-initialize API");
	api_deinit(&cfg->api);
	
	info("De-initialize log sub-system");
	log_deinit(&cfg->log);
	
	return 0;
}

int cfg_destroy(struct cfg *cfg)
{
	config_destroy(&cfg->cfg);

	web_destroy(&cfg->web);
	log_destroy(&cfg->log);
	api_destroy(&cfg->api);

	list_destroy(&cfg->plugins, (dtor_cb_t) plugin_destroy, false);
	list_destroy(&cfg->paths,   (dtor_cb_t) path_destroy, true);
	list_destroy(&cfg->nodes,   (dtor_cb_t) node_destroy, true);
	
	return 0;
}

int cfg_parse_cli(struct cfg *cfg, int argc, char *argv[])
{
	cfg->cli.argc = argc;
	cfg->cli.argv = argv;
	
	char *uri = (argc == 2) ? argv[1] : NULL;
	
	return cfg_parse(cfg, uri);
}

int cfg_parse(struct cfg *cfg, const char *uri)
{
	config_setting_t *cfg_root, *cfg_nodes, *cfg_paths, *cfg_plugins, *cfg_logging, *cfg_web;

	info("Parsing configuration: uri=%s", uri);

	int ret = CONFIG_FALSE;

	if (uri) {
		/* Setup libconfig */
		config_set_auto_convert(&cfg->cfg, 1);

		FILE *f;
		AFILE *af;
	
		/* Via stdin */
		if (strcmp("-", uri) == 0) {
			af = NULL;
			f = stdin;
		}
		/* Local file? */
		else if (access(uri, F_OK) != -1) {
			/* Setup libconfig include path.
			 * This is only supported for local files */
			char *uri_cpy = strdup(uri);
			char *include_dir = dirname(uri_cpy);

			config_set_include_dir(&cfg->cfg, include_dir);
				
			free(uri_cpy);

			af = NULL;
			f = fopen(uri, "r");
		}
		/* Use advio (libcurl) to fetch the config from a remote */
		else {
			af = afopen(uri, "r", ADVIO_MEM);
			f = af ? af->file : NULL;
		}

		/* Check if file could be loaded / opened */
		if (!f)
			error("Failed to open configuration from: %s", uri);
		
		/* Parse config */
		ret = config_read(&cfg->cfg, f);
		if (ret != CONFIG_TRUE)
			error("Failed to parse configuration: %s in %s:%d", config_error_text(&cfg->cfg), uri, config_error_line(&cfg->cfg));

		/* Close configuration file */
		if (af)
			afclose(af);
		else
			fclose(f);
	}
	else {
		warn("No configuration file specified. Starting unconfigured. Use the API to configure this instance.");

		cfg->web.port = 80;
		cfg->web.htdocs = "/villas/web/socket/";
	}

	/* Parse global settings */
	cfg_root = config_root_setting(&cfg->cfg);
	if (cfg_root) {
		if (!config_setting_is_group(cfg_root))
			warn("Missing global section in config file.");

		if (!config_setting_lookup_int(cfg_root, "affinity", &cfg->affinity))
			cfg->affinity = 0;

		if (!config_setting_lookup_int(cfg_root, "priority", &cfg->priority))
			cfg->priority = 0;

		if (!config_setting_lookup_float(cfg_root, "stats", &cfg->stats))
			cfg->stats = 0;
	}
	
	cfg_web = config_setting_get_member(cfg_root, "http");
	if (cfg_web)
		web_parse(&cfg->web, cfg_web);

	/* Parse logging settings */
	cfg_logging = config_setting_get_member(cfg_root, "logging");
	if (cfg_logging)
		log_parse(&cfg->log, cfg_logging);

	/* Parse plugins */
	cfg_plugins = config_setting_get_member(cfg_root, "plugins");
	if (cfg_plugins) {
		if (!config_setting_is_array(cfg_plugins))
			cerror(cfg_plugins, "Setting 'plugins' must be a list of strings");

		for (int i = 0; i < config_setting_length(cfg_plugins); i++) {
			struct config_setting_t *cfg_plugin = config_setting_get_elem(cfg_plugins, i);
			
			struct plugin plugin;
			
			ret = plugin_parse(&plugin, cfg_plugin);
			if (ret)
				cerror(cfg_plugin, "Failed to parse plugin");
			
			list_push(&cfg->plugins, memdup(&plugin, sizeof(plugin)));
		}
	}

	/* Parse nodes */
	cfg_nodes = config_setting_get_member(cfg_root, "nodes");
	if (cfg_nodes) {
		if (!config_setting_is_group(cfg_nodes))
			warn("Setting 'nodes' must be a group with node name => group mappings.");

		for (int i = 0; i < config_setting_length(cfg_nodes); i++) {
			config_setting_t *cfg_node = config_setting_get_elem(cfg_nodes, i);

			struct plugin *p;
			const char *type;

			/* Required settings */
			if (!config_setting_lookup_string(cfg_node, "type", &type))
				cerror(cfg_node, "Missing node type");
			
			
			p = plugin_lookup(PLUGIN_TYPE_NODE, type);
			if (!p)
				cerror(cfg_node, "Invalid node type: %s", type);
			
			struct node *n = node_create(&p->node);

			ret = node_parse(n, cfg_node);
			if (ret)
				cerror(cfg_node, "Failed to parse node");
			
			list_push(&cfg->nodes, n);
		}
	}

	/* Parse paths */
	cfg_paths = config_setting_get_member(cfg_root, "paths");
	if (cfg_paths) {
		if (!config_setting_is_list(cfg_paths))
			warn("Setting 'paths' must be a list.");

		for (int i = 0; i < config_setting_length(cfg_paths); i++) {
			config_setting_t *cfg_path = config_setting_get_elem(cfg_paths, i);

			struct path *p = path_create();
			
			ret = path_parse(p, cfg_path, &cfg->nodes);
			if (ret)
				cerror(cfg_path, "Failed to parse path");
			
			list_push(&cfg->paths, p);

			if (p->reverse) {
				struct path *r = path_create();
		
				ret = path_reverse(p, r);
				if (ret)
					cerror(cfg_path, "Failed to reverse path %s", path_name(p));

				list_push(&cfg->paths, r);
			}
		}
	}

	return 0;
}