/* Copyright (c) 2015, Vsevolod Stakhov
 * All rights reserved.
 *
 * Redistribution and use 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.
 *
 * THIS SOFTWARE IS PROVIDED ''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 AUTHOR 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 "lua_common.h"
#include "task.h"
#include "main.h"
#include "cfg_rcl.h"

/***
 * @function util.create_event_base()
 * Creates new event base for processing asynchronous events
 * @return {ev_base} new event processing base
 */
LUA_FUNCTION_DEF (util, create_event_base);
/***
 * @function util.load_rspamd_config(filename)
 * Load rspamd config from the specified file
 * @return {confg} new configuration object suitable for access
 */
LUA_FUNCTION_DEF (util, load_rspamd_config);
/***
 * @function util.config_from_ucl(any)
 * Load rspamd config from ucl reperesented by any lua table
 * @return {confg} new configuration object suitable for access
 */
LUA_FUNCTION_DEF (util, config_from_ucl);
LUA_FUNCTION_DEF (util, process_message);

static const struct luaL_reg utillib_f[] = {
	LUA_INTERFACE_DEF (util, create_event_base),
	LUA_INTERFACE_DEF (util, load_rspamd_config),
	LUA_INTERFACE_DEF (util, config_from_ucl),
	LUA_INTERFACE_DEF (util, process_message),
	{NULL, NULL}
};

static gint
lua_util_create_event_base (lua_State *L)
{
	struct event_base **pev_base;

	pev_base = lua_newuserdata (L, sizeof (struct event_base *));
	rspamd_lua_setclass (L, "rspamd{ev_base}", -1);
	*pev_base = event_init ();

	return 1;
}

static gint
lua_util_load_rspamd_config (lua_State *L)
{
	struct rspamd_config *cfg, **pcfg;
	const gchar *cfg_name;

	cfg_name = luaL_checkstring (L, 1);

	if (cfg_name) {
		cfg = g_malloc0 (sizeof (struct rspamd_config));
		rspamd_init_cfg (cfg, FALSE);

		if (rspamd_config_read (cfg, cfg_name, NULL, NULL, NULL)) {
			msg_err ("cannot load config from %s", cfg_name);
			lua_pushnil (L);
		}
		else {
			rspamd_config_post_load (cfg);
			init_symbols_cache (cfg->cfg_pool, cfg->cache, cfg, NULL, TRUE);
			pcfg = lua_newuserdata (L, sizeof (struct rspamd_config *));
			rspamd_lua_setclass (L, "rspamd{config}", -1);
			*pcfg = cfg;
		}
	}

	return 1;
}

static gint
lua_util_config_from_ucl (lua_State *L)
{
	struct rspamd_config *cfg, **pcfg;
	struct rspamd_rcl_section *top;
	GError *err = NULL;
	ucl_object_t *obj;

	obj = ucl_object_lua_import (L, 1);

	if (obj) {
		cfg = g_malloc0 (sizeof (struct rspamd_config));
		rspamd_init_cfg (cfg, FALSE);
		cfg->lua_state = L;
		cfg->rcl_obj = obj;
		top = rspamd_rcl_config_init ();

		if (!rspamd_rcl_parse (top, cfg, cfg->cfg_pool, cfg->rcl_obj, &err)) {
			msg_err ("rcl parse error: %s", err->message);
			ucl_object_unref (obj);
			lua_pushnil (L);
		}
		else {
			rspamd_config_post_load (cfg);
			init_symbols_cache (cfg->cfg_pool, cfg->cache, cfg, NULL, TRUE);
			pcfg = lua_newuserdata (L, sizeof (struct rspamd_config *));
			rspamd_lua_setclass (L, "rspamd{config}", -1);
			*pcfg = cfg;
		}
	}

	return 1;
}

static gboolean
lua_util_task_fin (struct rspamd_task *task, void *ud)
{
	ucl_object_t **target = ud;

	*target = rspamd_protocol_write_ucl (task, NULL);
	rdns_resolver_release (task->resolver->r);

	return TRUE;
}

static gint
lua_util_process_message (lua_State *L)
{
	struct rspamd_config *cfg = lua_check_config (L, 1);
	const gchar *message;
	gsize mlen;
	struct rspamd_task *task;
	struct event_base *base;
	ucl_object_t *res = NULL;

	message = luaL_checklstring (L, 2, &mlen);

	if (cfg != NULL && message != NULL) {
		base = event_init ();
		rspamd_init_filters (cfg, FALSE);
		task = rspamd_task_new (NULL);
		task->cfg = cfg;
		task->ev_base = base;
		task->msg.start = rspamd_mempool_alloc (task->task_pool, mlen + 1);
		rspamd_strlcpy ((gpointer)task->msg.start, message, mlen + 1);
		task->msg.len = mlen;
		task->fin_callback = lua_util_task_fin;
		task->fin_arg = &res;
		task->resolver = dns_resolver_init (NULL, base, cfg);
		task->s = new_async_session (task->task_pool, rspamd_task_fin,
					rspamd_task_restore, rspamd_task_free_hard, task);

		if (rspamd_task_process (task, NULL, message, mlen, NULL, TRUE)) {
			event_base_loop (base, 0);

			if (res != NULL) {
				ucl_object_push_lua (L, res, true);

				ucl_object_unref (res);
			}
			else {
				ucl_object_push_lua (L, rspamd_protocol_write_ucl (task, NULL),
						true);
				rdns_resolver_release (task->resolver->r);
				rspamd_task_free_hard (task);
			}
		}
		else {
			lua_pushnil (L);
		}

		event_base_free (base);
	}
	else {
		lua_pushnil (L);
	}

	return 1;
}

static gint
lua_load_util (lua_State * L)
{
	lua_newtable (L);
	luaL_register (L, NULL, utillib_f);

	return 1;
}

void
luaopen_util (lua_State * L)
{
	rspamd_lua_add_preload (L, "rspamd_util", lua_load_util);
}