/*
Minetest
Copyright (C) 2013 sapier

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "lua_api/l_mainmenu.h"
#include "lua_api/l_internal.h"
#include "common/c_content.h"
#include "cpp_api/s_async.h"
#include "scripting_mainmenu.h"
#include "gui/guiEngine.h"
#include "gui/guiMainMenu.h"
#include "gui/guiKeyChangeMenu.h"
#include "gui/guiPathSelectMenu.h"
#include "version.h"
#include "porting.h"
#include "filesys.h"
#include "convert_json.h"
#include "content/content.h"
#include "content/subgames.h"
#include "serverlist.h"
#include "mapgen/mapgen.h"
#include "settings.h"
#include "client/client.h"
#include "client/renderingengine.h"
#include "network/networkprotocol.h"
#include "content/mod_configuration.h"
#include "threading/mutex_auto_lock.h"

/******************************************************************************/
std::string ModApiMainMenu::getTextData(lua_State *L, std::string name)
{
	lua_getglobal(L, "gamedata");

	lua_getfield(L, -1, name.c_str());

	if(lua_isnil(L, -1))
		return "";

	return luaL_checkstring(L, -1);
}

/******************************************************************************/
int ModApiMainMenu::getIntegerData(lua_State *L, std::string name,bool& valid)
{
	lua_getglobal(L, "gamedata");

	lua_getfield(L, -1, name.c_str());

	if(lua_isnil(L, -1)) {
		valid = false;
		return -1;
		}

	valid = true;
	return luaL_checkinteger(L, -1);
}

/******************************************************************************/
int ModApiMainMenu::getBoolData(lua_State *L, std::string name,bool& valid)
{
	lua_getglobal(L, "gamedata");

	lua_getfield(L, -1, name.c_str());

	if(lua_isnil(L, -1)) {
		valid = false;
		return false;
		}

	valid = true;
	return readParam<bool>(L, -1);
}

/******************************************************************************/
int ModApiMainMenu::l_update_formspec(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	if (engine->m_startgame)
		return 0;

	//read formspec
	std::string formspec(luaL_checkstring(L, 1));

	if (engine->m_formspecgui != 0) {
		engine->m_formspecgui->setForm(formspec);
	}

	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_set_formspec_prepend(lua_State *L)
{
	GUIEngine *engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	if (engine->m_startgame)
		return 0;

	std::string formspec(luaL_checkstring(L, 1));
	engine->setFormspecPrepend(formspec);

	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_start(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	//update c++ gamedata from lua table

	bool valid = false;

	MainMenuData *data = engine->m_data;

	data->selected_world = getIntegerData(L, "selected_world",valid) -1;
	data->simple_singleplayer_mode = getBoolData(L,"singleplayer",valid);
	data->do_reconnect = getBoolData(L, "do_reconnect", valid);
	if (!data->do_reconnect) {
		data->name     = getTextData(L,"playername");
		data->password = getTextData(L,"password");
		data->address  = getTextData(L,"address");
		data->port     = getTextData(L,"port");

		const auto val = getTextData(L, "allow_login_or_register");
		if (val == "login")
			data->allow_login_or_register = ELoginRegister::Login;
		else if (val == "register")
			data->allow_login_or_register = ELoginRegister::Register;
		else
			data->allow_login_or_register = ELoginRegister::Any;
	}
	data->serverdescription = getTextData(L,"serverdescription");
	data->servername        = getTextData(L,"servername");

	//close menu next time
	engine->m_startgame = true;
	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_close(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	engine->m_kill = true;
	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_set_background(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	std::string backgroundlevel(luaL_checkstring(L, 1));
	std::string texturename(luaL_checkstring(L, 2));

	bool tile_image = false;
	bool retval     = false;
	unsigned int minsize = 16;

	if (!lua_isnone(L, 3)) {
		tile_image = readParam<bool>(L, 3);
	}

	if (!lua_isnone(L, 4)) {
		minsize = lua_tonumber(L, 4);
	}

	if (backgroundlevel == "background") {
		retval |= engine->setTexture(TEX_LAYER_BACKGROUND, texturename,
				tile_image, minsize);
	}

	if (backgroundlevel == "overlay") {
		retval |= engine->setTexture(TEX_LAYER_OVERLAY, texturename,
				tile_image, minsize);
	}

	if (backgroundlevel == "header") {
		retval |= engine->setTexture(TEX_LAYER_HEADER,  texturename,
				tile_image, minsize);
	}

	if (backgroundlevel == "footer") {
		retval |= engine->setTexture(TEX_LAYER_FOOTER, texturename,
				tile_image, minsize);
	}

	lua_pushboolean(L,retval);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_set_clouds(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	bool value = readParam<bool>(L,1);

	engine->m_clouds_enabled = value;

	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_get_textlist_index(lua_State *L)
{
	// get_table_index accepts both tables and textlists
	return l_get_table_index(L);
}

/******************************************************************************/
int ModApiMainMenu::l_get_table_index(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	std::string tablename(luaL_checkstring(L, 1));
	GUITable *table = engine->m_menu->getTable(tablename);
	s32 selection = table ? table->getSelected() : 0;

	if (selection >= 1)
		lua_pushinteger(L, selection);
	else
		lua_pushnil(L);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_worlds(lua_State *L)
{
	std::vector<WorldSpec> worlds = getAvailableWorlds();

	lua_newtable(L);
	int top = lua_gettop(L);
	unsigned int index = 1;

	for (const WorldSpec &world : worlds) {
		lua_pushnumber(L,index);

		lua_newtable(L);
		int top_lvl2 = lua_gettop(L);

		lua_pushstring(L,"path");
		lua_pushstring(L, world.path.c_str());
		lua_settable(L, top_lvl2);

		lua_pushstring(L,"name");
		lua_pushstring(L, world.name.c_str());
		lua_settable(L, top_lvl2);

		lua_pushstring(L,"gameid");
		lua_pushstring(L, world.gameid.c_str());
		lua_settable(L, top_lvl2);

		lua_settable(L, top);
		index++;
	}
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_games(lua_State *L)
{
	std::vector<SubgameSpec> games = getAvailableGames();

	lua_newtable(L);
	int top = lua_gettop(L);
	unsigned int index = 1;

	for (const SubgameSpec &game : games) {
		lua_pushnumber(L, index);
		lua_newtable(L);
		int top_lvl2 = lua_gettop(L);

		lua_pushstring(L,  "id");
		lua_pushstring(L,  game.id.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "path");
		lua_pushstring(L,  game.path.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "type");
		lua_pushstring(L,  "game");
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "gamemods_path");
		lua_pushstring(L,  game.gamemods_path.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "name");
		lua_pushstring(L,  game.title.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "title");
		lua_pushstring(L,  game.title.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "author");
		lua_pushstring(L,  game.author.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "release");
		lua_pushinteger(L, game.release);
		lua_settable(L,    top_lvl2);

		lua_pushstring(L,  "menuicon_path");
		lua_pushstring(L,  game.menuicon_path.c_str());
		lua_settable(L,    top_lvl2);

		lua_pushstring(L, "addon_mods_paths");
		lua_newtable(L);
		int table2 = lua_gettop(L);
		int internal_index = 1;
		for (const auto &addon_mods_path : game.addon_mods_paths) {
			lua_pushnumber(L, internal_index);
			lua_pushstring(L, addon_mods_path.second.c_str());
			lua_settable(L,   table2);
			internal_index++;
		}
		lua_settable(L, top_lvl2);
		lua_settable(L, top);
		index++;
	}
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_content_info(lua_State *L)
{
	std::string path = luaL_checkstring(L, 1);

	ContentSpec spec;
	spec.path = path;
	parseContentInfo(spec);

	lua_newtable(L);

	lua_pushstring(L, spec.name.c_str());
	lua_setfield(L, -2, "name");

	lua_pushstring(L, spec.type.c_str());
	lua_setfield(L, -2, "type");

	lua_pushstring(L, spec.author.c_str());
	lua_setfield(L, -2, "author");

	if (!spec.title.empty()) {
		lua_pushstring(L, spec.title.c_str());
		lua_setfield(L, -2, "title");
	}

	lua_pushinteger(L, spec.release);
	lua_setfield(L, -2, "release");

	lua_pushstring(L, spec.desc.c_str());
	lua_setfield(L, -2, "description");

	lua_pushstring(L, spec.path.c_str());
	lua_setfield(L, -2, "path");

	if (spec.type == "mod") {
		ModSpec spec;
		spec.path = path;
		parseModContents(spec);

		// Dependencies
		lua_newtable(L);
		int i = 1;
		for (const auto &dep : spec.depends) {
			lua_pushstring(L, dep.c_str());
			lua_rawseti(L, -2, i++);
		}
		lua_setfield(L, -2, "depends");

		// Optional Dependencies
		lua_newtable(L);
		i = 1;
		for (const auto &dep : spec.optdepends) {
			lua_pushstring(L, dep.c_str());
			lua_rawseti(L, -2, i++);
		}
		lua_setfield(L, -2, "optional_depends");
	}

	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_check_mod_configuration(lua_State *L)
{
	std::string worldpath = luaL_checkstring(L, 1);

	ModConfiguration modmgr;

	// Add all game mods
	SubgameSpec gamespec = findWorldSubgame(worldpath);
	modmgr.addGameMods(gamespec);
	modmgr.addModsInPath(worldpath + DIR_DELIM + "worldmods", "worldmods");

	// Add user-configured mods
	std::vector<ModSpec> modSpecs;

	luaL_checktype(L, 2, LUA_TTABLE);

	lua_pushnil(L);
	while (lua_next(L, 2)) {
		// Ignore non-string keys
		if (lua_type(L, -2) != LUA_TSTRING) {
			throw LuaError(
					"Unexpected non-string key in table passed to "
					"core.check_mod_configuration");
		}

		std::string modpath = luaL_checkstring(L, -1);
		lua_pop(L, 1);
		std::string virtual_path = lua_tostring(L, -1);

		modSpecs.emplace_back();
		ModSpec &spec = modSpecs.back();
		spec.name = fs::GetFilenameFromPath(modpath.c_str());
		spec.path = modpath;
		spec.virtual_path = virtual_path;
		if (!parseModContents(spec)) {
			throw LuaError("Not a mod!");
		}
	}

	modmgr.addMods(modSpecs);
	try {
		modmgr.checkConflictsAndDeps();
	} catch (const ModError &err) {
		errorstream << err.what() << std::endl;

		lua_newtable(L);

		lua_pushboolean(L, false);
		lua_setfield(L, -2, "is_consistent");

		lua_newtable(L);
		lua_setfield(L, -2, "unsatisfied_mods");

		lua_newtable(L);
		lua_setfield(L, -2, "satisfied_mods");

		lua_pushstring(L, err.what());
		lua_setfield(L, -2, "error_message");
		return 1;
	}


	lua_newtable(L);

	lua_pushboolean(L, modmgr.isConsistent());
	lua_setfield(L, -2, "is_consistent");

	lua_newtable(L);
	int top = lua_gettop(L);
	unsigned int index = 1;
	for (const auto &spec : modmgr.getUnsatisfiedMods()) {
		lua_pushnumber(L, index);
		push_mod_spec(L, spec, true);
		lua_settable(L, top);
		index++;
	}

	lua_setfield(L, -2, "unsatisfied_mods");

	lua_newtable(L);
	top = lua_gettop(L);
	index = 1;
	for (const auto &spec : modmgr.getMods()) {
		lua_pushnumber(L, index);
		push_mod_spec(L, spec, false);
		lua_settable(L, top);
		index++;
	}
	lua_setfield(L, -2, "satisfied_mods");

	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_show_keys_menu(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	GUIKeyChangeMenu *kmenu = new GUIKeyChangeMenu(
			engine->m_rendering_engine->get_gui_env(),
			engine->m_parent,
			-1,
			engine->m_menumanager,
			engine->m_texture_source);
	kmenu->drop();
	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_create_world(lua_State *L)
{
	const char *name   = luaL_checkstring(L, 1);
	const char *gameid = luaL_checkstring(L, 2);

	StringMap use_settings;
	luaL_checktype(L, 3, LUA_TTABLE);
	lua_pushnil(L);
	while (lua_next(L, 3) != 0) {
		// key at index -2 and value at index -1
		use_settings[luaL_checkstring(L, -2)] = luaL_checkstring(L, -1);
		lua_pop(L, 1);
	}
	lua_pop(L, 1);

	std::string path = porting::path_user + DIR_DELIM
			"worlds" + DIR_DELIM
			+ sanitizeDirName(name, "world_");

	std::vector<SubgameSpec> games = getAvailableGames();
	auto game_it = std::find_if(games.begin(), games.end(), [gameid] (const SubgameSpec &spec) {
		return spec.id == gameid;
	});
	if (game_it == games.end()) {
		lua_pushstring(L, "Game ID not found");
		return 1;
	}

	// Set the settings for world creation
	// this is a bad hack but the best we have right now..
	StringMap backup;
	for (auto it : use_settings) {
		if (g_settings->existsLocal(it.first))
			backup[it.first] = g_settings->get(it.first);
		g_settings->set(it.first, it.second);
	}

	// Create world if it doesn't exist
	try {
		loadGameConfAndInitWorld(path, name, *game_it, true);
		lua_pushnil(L);
	} catch (const BaseException &e) {
		auto err = std::string("Failed to initialize world: ") + e.what();
		lua_pushstring(L, err.c_str());
	}

	// Restore previous settings
	for (auto it : use_settings) {
		auto it2 = backup.find(it.first);
		if (it2 == backup.end())
			g_settings->remove(it.first); // wasn't set before
		else
			g_settings->set(it.first, it2->second); // was set before
	}

	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_delete_world(lua_State *L)
{
	int world_id = luaL_checkinteger(L, 1) - 1;
	std::vector<WorldSpec> worlds = getAvailableWorlds();
	if (world_id < 0 || world_id >= (int) worlds.size()) {
		lua_pushstring(L, "Invalid world index");
		return 1;
	}
	const WorldSpec &spec = worlds[world_id];
	if (!fs::RecursiveDelete(spec.path)) {
		lua_pushstring(L, "Failed to delete world");
		return 1;
	}
	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_set_topleft_text(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	std::string text;

	if (!lua_isnone(L,1) &&	!lua_isnil(L,1))
		text = luaL_checkstring(L, 1);

	engine->setTopleftText(text);
	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_get_mapgen_names(lua_State *L)
{
	std::vector<const char *> names;
	bool include_hidden = lua_isboolean(L, 1) && readParam<bool>(L, 1);
	Mapgen::getMapgenNames(&names, include_hidden);

	lua_newtable(L);
	for (size_t i = 0; i != names.size(); i++) {
		lua_pushstring(L, names[i]);
		lua_rawseti(L, -2, i + 1);
	}

	return 1;
}


/******************************************************************************/
int ModApiMainMenu::l_get_user_path(lua_State *L)
{
	std::string path = fs::RemoveRelativePathComponents(porting::path_user);
	lua_pushstring(L, path.c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_modpath(lua_State *L)
{
	std::string modpath = fs::RemoveRelativePathComponents(
		porting::path_user + DIR_DELIM + "mods" + DIR_DELIM);
	lua_pushstring(L, modpath.c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_modpaths(lua_State *L)
{
	lua_newtable(L);

	ModApiMainMenu::l_get_modpath(L);
	lua_setfield(L, -2, "mods");

	for (const std::string &component : getEnvModPaths()) {
		lua_pushstring(L, component.c_str());
		lua_setfield(L, -2, fs::AbsolutePath(component).c_str());
	}
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_clientmodpath(lua_State *L)
{
	std::string modpath = fs::RemoveRelativePathComponents(
		porting::path_user + DIR_DELIM + "clientmods" + DIR_DELIM);
	lua_pushstring(L, modpath.c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_gamepath(lua_State *L)
{
	std::string gamepath = fs::RemoveRelativePathComponents(
		porting::path_user + DIR_DELIM + "games" + DIR_DELIM);
	lua_pushstring(L, gamepath.c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_texturepath(lua_State *L)
{
	std::string gamepath = fs::RemoveRelativePathComponents(
		porting::path_user + DIR_DELIM + "textures");
	lua_pushstring(L, gamepath.c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_texturepath_share(lua_State *L)
{
	std::string gamepath = fs::RemoveRelativePathComponents(
		porting::path_share + DIR_DELIM + "textures");
	lua_pushstring(L, gamepath.c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_cache_path(lua_State *L)
{
	lua_pushstring(L, fs::RemoveRelativePathComponents(porting::path_cache).c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_temp_path(lua_State *L)
{
	if (lua_isnoneornil(L, 1) || !lua_toboolean(L, 1))
		lua_pushstring(L, fs::TempPath().c_str());
	else
		lua_pushstring(L, fs::CreateTempFile().c_str());
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_create_dir(lua_State *L) {
	const char *path = luaL_checkstring(L, 1);

	if (ModApiMainMenu::mayModifyPath(path)) {
		lua_pushboolean(L, fs::CreateAllDirs(path));
		return 1;
	}

	lua_pushboolean(L, false);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_delete_dir(lua_State *L)
{
	const char *path = luaL_checkstring(L, 1);

	std::string absolute_path = fs::RemoveRelativePathComponents(path);

	if (ModApiMainMenu::mayModifyPath(absolute_path)) {
		lua_pushboolean(L, fs::RecursiveDelete(absolute_path));
		return 1;
	}

	lua_pushboolean(L, false);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_copy_dir(lua_State *L)
{
	const char *source	= luaL_checkstring(L, 1);
	const char *destination	= luaL_checkstring(L, 2);

	bool keep_source = true;
	if (!lua_isnoneornil(L, 3))
		keep_source = readParam<bool>(L, 3);

	std::string abs_destination = fs::RemoveRelativePathComponents(destination);
	std::string abs_source = fs::RemoveRelativePathComponents(source);

	if (!ModApiMainMenu::mayModifyPath(abs_destination) ||
		(!keep_source && !ModApiMainMenu::mayModifyPath(abs_source))) {
		lua_pushboolean(L, false);
		return 1;
	}

	bool retval;
	if (keep_source)
		retval = fs::CopyDir(abs_source, abs_destination);
	else
		retval = fs::MoveDir(abs_source, abs_destination);
	lua_pushboolean(L, retval);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_is_dir(lua_State *L)
{
	const char *path = luaL_checkstring(L, 1);

	lua_pushboolean(L, fs::IsDir(path));
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_extract_zip(lua_State *L)
{
	const char *zipfile	= luaL_checkstring(L, 1);
	const char *destination	= luaL_checkstring(L, 2);

	std::string absolute_destination = fs::RemoveRelativePathComponents(destination);

	if (ModApiMainMenu::mayModifyPath(absolute_destination)) {
		auto fs = RenderingEngine::get_raw_device()->getFileSystem();
		bool ok = fs::extractZipFile(fs, zipfile, destination);
		lua_pushboolean(L, ok);
		return 1;
	}

	lua_pushboolean(L,false);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_mainmenu_path(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	lua_pushstring(L,engine->getScriptDir().c_str());
	return 1;
}

/******************************************************************************/
bool ModApiMainMenu::mayModifyPath(std::string path)
{
	path = fs::RemoveRelativePathComponents(path);

	if (fs::PathStartsWith(path, fs::TempPath()))
		return true;

	std::string path_user = fs::RemoveRelativePathComponents(porting::path_user);

	if (fs::PathStartsWith(path, path_user + DIR_DELIM "client"))
		return true;
	if (fs::PathStartsWith(path, path_user + DIR_DELIM "games"))
		return true;
	if (fs::PathStartsWith(path, path_user + DIR_DELIM "mods"))
		return true;
	if (fs::PathStartsWith(path, path_user + DIR_DELIM "textures"))
		return true;
	if (fs::PathStartsWith(path, path_user + DIR_DELIM "worlds"))
		return true;

	if (fs::PathStartsWith(path, fs::RemoveRelativePathComponents(porting::path_cache)))
		return true;

	return false;
}


/******************************************************************************/
int ModApiMainMenu::l_may_modify_path(lua_State *L)
{
	const char *target = luaL_checkstring(L, 1);
	std::string absolute_destination = fs::RemoveRelativePathComponents(target);
	lua_pushboolean(L, ModApiMainMenu::mayModifyPath(absolute_destination));
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_show_path_select_dialog(lua_State *L)
{
	GUIEngine* engine = getGuiEngine(L);
	sanity_check(engine != NULL);

	const char *formname= luaL_checkstring(L, 1);
	const char *title	= luaL_checkstring(L, 2);
	bool is_file_select = readParam<bool>(L, 3);

	GUIFileSelectMenu* fileOpenMenu =
		new GUIFileSelectMenu(engine->m_rendering_engine->get_gui_env(),
				engine->m_parent,
				-1,
				engine->m_menumanager,
				title,
				formname,
				is_file_select);
	fileOpenMenu->setTextDest(engine->m_buttonhandler);
	fileOpenMenu->drop();
	return 0;
}

/******************************************************************************/
int ModApiMainMenu::l_download_file(lua_State *L)
{
	const char *url    = luaL_checkstring(L, 1);
	const char *target = luaL_checkstring(L, 2);

	//check path
	std::string absolute_destination = fs::RemoveRelativePathComponents(target);

	if (ModApiMainMenu::mayModifyPath(absolute_destination)) {
		if (GUIEngine::downloadFile(url,absolute_destination)) {
			lua_pushboolean(L,true);
			return 1;
		}
	} else {
		errorstream << "DOWNLOAD denied: " << absolute_destination
				<< " isn't an allowed path" << std::endl;
	}
	lua_pushboolean(L,false);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_video_drivers(lua_State *L)
{
	std::vector<irr::video::E_DRIVER_TYPE> drivers = RenderingEngine::getSupportedVideoDrivers();

	lua_newtable(L);
	for (u32 i = 0; i != drivers.size(); i++) {
		auto &info = RenderingEngine::getVideoDriverInfo(drivers[i]);

		lua_newtable(L);
		lua_pushstring(L, info.name.c_str());
		lua_setfield(L, -2, "name");
		lua_pushstring(L, info.friendly_name.c_str());
		lua_setfield(L, -2, "friendly_name");

		lua_rawseti(L, -2, i + 1);
	}

	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_gettext(lua_State *L)
{
	const char *srctext = luaL_checkstring(L, 1);
	const char *text = *srctext ? gettext(srctext) : "";
	lua_pushstring(L, text);

	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_screen_info(lua_State *L)
{
	lua_newtable(L);
	int top = lua_gettop(L);
	lua_pushstring(L,"density");
	lua_pushnumber(L,RenderingEngine::getDisplayDensity());
	lua_settable(L, top);

	const v2u32 &window_size = RenderingEngine::getWindowSize();
	lua_pushstring(L,"window_width");
	lua_pushnumber(L, window_size.X);
	lua_settable(L, top);

	lua_pushstring(L,"window_height");
	lua_pushnumber(L, window_size.Y);
	lua_settable(L, top);

	lua_pushstring(L, "render_info");
	lua_pushstring(L, wide_to_utf8(RenderingEngine::get_video_driver()->getName()).c_str());
	lua_settable(L, top);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_get_min_supp_proto(lua_State *L)
{
	lua_pushinteger(L, CLIENT_PROTOCOL_VERSION_MIN);
	return 1;
}

int ModApiMainMenu::l_get_max_supp_proto(lua_State *L)
{
	lua_pushinteger(L, CLIENT_PROTOCOL_VERSION_MAX);
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_open_url(lua_State *L)
{
	std::string url = luaL_checkstring(L, 1);
	lua_pushboolean(L, porting::open_url(url));
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_open_dir(lua_State *L)
{
	std::string path = luaL_checkstring(L, 1);
	lua_pushboolean(L, porting::open_directory(path));
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_share_file(lua_State *L)
{
#ifdef __ANDROID__
	std::string path = luaL_checkstring(L, 1);
	porting::shareFileAndroid(path);
	lua_pushboolean(L, true);
#else
	lua_pushboolean(L, false);
#endif
	return 1;
}

/******************************************************************************/
int ModApiMainMenu::l_do_async_callback(lua_State *L)
{
	MainMenuScripting *script = getScriptApi<MainMenuScripting>(L);

	size_t func_length, param_length;
	const char* serialized_func_raw = luaL_checklstring(L, 1, &func_length);
	const char* serialized_param_raw = luaL_checklstring(L, 2, &param_length);

	sanity_check(serialized_func_raw != NULL);
	sanity_check(serialized_param_raw != NULL);

	u32 jobId = script->queueAsync(
		std::string(serialized_func_raw, func_length),
		std::string(serialized_param_raw, param_length));

	lua_pushinteger(L, jobId);

	return 1;
}

/******************************************************************************/
// this is intentionally a global and not part of MainMenuScripting or such
namespace {
	std::unordered_map<std::string, std::string> once_values;
	std::mutex once_mutex;
}

int ModApiMainMenu::l_set_once(lua_State *L)
{
	std::string key = readParam<std::string>(L, 1);
	if (lua_isnil(L, 2))
		return 0;
	std::string value = readParam<std::string>(L, 2);

	{
		MutexAutoLock lock(once_mutex);
		once_values[key] = value;
	}

	return 0;
}

int ModApiMainMenu::l_get_once(lua_State *L)
{
	std::string key = readParam<std::string>(L, 1);

	{
		MutexAutoLock lock(once_mutex);
		auto it = once_values.find(key);
		if (it == once_values.end())
			lua_pushnil(L);
		else
			lua_pushstring(L, it->second.c_str());
	}

	return 1;
}

/******************************************************************************/
void ModApiMainMenu::Initialize(lua_State *L, int top)
{
	API_FCT(update_formspec);
	API_FCT(set_formspec_prepend);
	API_FCT(set_clouds);
	API_FCT(get_textlist_index);
	API_FCT(get_table_index);
	API_FCT(get_worlds);
	API_FCT(get_games);
	API_FCT(get_content_info);
	API_FCT(check_mod_configuration);
	API_FCT(start);
	API_FCT(close);
	API_FCT(show_keys_menu);
	API_FCT(create_world);
	API_FCT(delete_world);
	API_FCT(set_background);
	API_FCT(set_topleft_text);
	API_FCT(get_mapgen_names);
	API_FCT(get_user_path);
	API_FCT(get_modpath);
	API_FCT(get_modpaths);
	API_FCT(get_clientmodpath);
	API_FCT(get_gamepath);
	API_FCT(get_texturepath);
	API_FCT(get_texturepath_share);
	API_FCT(get_cache_path);
	API_FCT(get_temp_path);
	API_FCT(create_dir);
	API_FCT(delete_dir);
	API_FCT(copy_dir);
	API_FCT(is_dir);
	API_FCT(extract_zip);
	API_FCT(may_modify_path);
	API_FCT(get_mainmenu_path);
	API_FCT(show_path_select_dialog);
	API_FCT(download_file);
	API_FCT(gettext);
	API_FCT(get_video_drivers);
	API_FCT(get_screen_info);
	API_FCT(get_min_supp_proto);
	API_FCT(get_max_supp_proto);
	API_FCT(open_url);
	API_FCT(open_dir);
	API_FCT(share_file);
	API_FCT(do_async_callback);
	API_FCT(set_once);
	API_FCT(get_once);
}

/******************************************************************************/
void ModApiMainMenu::InitializeAsync(lua_State *L, int top)
{
	API_FCT(get_worlds);
	API_FCT(get_games);
	API_FCT(get_mapgen_names);
	API_FCT(get_user_path);
	API_FCT(get_modpath);
	API_FCT(get_modpaths);
	API_FCT(get_clientmodpath);
	API_FCT(get_gamepath);
	API_FCT(get_texturepath);
	API_FCT(get_texturepath_share);
	API_FCT(get_cache_path);
	API_FCT(get_temp_path);
	API_FCT(create_dir);
	API_FCT(delete_dir);
	API_FCT(copy_dir);
	API_FCT(is_dir);
	API_FCT(extract_zip);
	API_FCT(may_modify_path);
	API_FCT(download_file);
	API_FCT(get_min_supp_proto);
	API_FCT(get_max_supp_proto);
	API_FCT(gettext);
}