Minetest Lua Mainmenu API Reference 0.4.9
========================================

Introduction
-------------
The main menu is defined as a formspec by Lua in builtin/mainmenu.lua
Description of formspec language to show your menu is in lua_api.txt

Callbacks
---------
engine.buttonhandler(fields): called when a button is pressed.
^ fields = {name1 = value1, name2 = value2, ...}
engine.event_handler(event)
^ event: "MenuQuit", "KeyEnter", "ExitButton" or "EditBoxEnter"

Gamedata
--------
The "gamedata" table is read when calling engine.start(). It should contain:
{
	playername     = <name>,
	password       = <password>,
	address        = <IP/adress>,
	port           = <port>,
	selected_world = <index>, -- 0 for client mode
	singleplayer   = <true/false>,
}

Functions
---------
engine.start()
engine.close()

Filesystem:
engine.get_scriptdir()
^ returns directory of script
engine.get_modpath() (possible in async calls)
^ returns path to global modpath
engine.get_modstore_details(modid) (possible in async calls)
^ modid numeric id of mod in modstore
^ returns {
	id			= <numeric id of mod in modstore>,
	title		= <human readable title>,
	basename	= <basename for mod>,
	description = <description of mod>,
	author		= <author of mod>,
	download_url= <best match download url>,
	license		= <short description of license>,
	rating		= <float value of current rating>
}
engine.get_modstore_list() (possible in async calls)
^ returns {
	[1] = {
		id		 = <numeric id of mod in modstore>,
		title	 = <human readable title>,
		basename = <basename for mod>
	}
}
engine.get_gamepath() (possible in async calls)
^ returns path to global gamepath
engine.get_texturepath() (possible in async calls)
^ returns path to default textures
engine.get_dirlist(path,onlydirs) (possible in async calls)
^ path to get subdirs from
^ onlydirs should result contain only dirs?
^ returns list of folders within path
engine.create_dir(absolute_path) (possible in async calls)
^ absolute_path to directory to create (needs to be absolute)
^ returns true/false
engine.delete_dir(absolute_path) (possible in async calls)
^ absolute_path to directory to delete (needs to be absolute)
^ returns true/false
engine.copy_dir(source,destination,keep_soure) (possible in async calls)
^ source folder
^ destination folder
^ keep_source DEFAULT true --> if set to false source is deleted after copying
^ returns true/false
engine.extract_zip(zipfile,destination) [unzip within path required]
^ zipfile to extract
^ destination folder to extract to
^ returns true/false
engine.download_file(url,target) (possible in async calls)
^ url to download
^ target to store to
^ returns true/false
engine.get_version() (possible in async calls)
^ returns current minetest version
engine.sound_play(spec, looped) -> handle
^ spec = SimpleSoundSpec (see lua-api.txt)
^ looped = bool
engine.sound_stop(handle)

Formspec:
engine.update_formspec(formspec)
engine.get_table_index(tablename) -> index
^ can also handle textlists
engine.formspec_escape(string) -> string
^ escapes characters [ ] \ , ; that can not be used in formspecs
engine.explode_table_event(string) -> table
^ returns e.g. {type="CHG", row=1, column=2}
^ type: "INV" (no row selected), "CHG" (selected) or "DCL" (double-click)
engine.explode_textlist_event(string) -> table
^ returns e.g. {type="CHG", index=1}
^ type: "INV" (no row selected), "CHG" (selected) or "DCL" (double-click)

GUI:
engine.set_background(type, texturepath)
^ type: "background", "overlay", "header" or "footer"
engine.set_clouds(<true/false>)
engine.set_topleft_text(text)
engine.show_keys_menu()
engine.file_open_dialog(formname,caption)
^ shows a file open dialog
^ formname is base name of dialog response returned in fields
^     -if dialog was accepted "_accepted"
^^       will be added to fieldname containing the path
^     -if dialog was canceled "_cancelled"
^        will be added to fieldname value is set to formname itself
^ returns nil or selected file/folder

Games:
engine.get_game(index)
^ returns {
	id               = <id>,
	path             = <full path to game>,
	gamemods_path    = <path>,
	name             = <name of game>,
	menuicon_path    = <full path to menuicon>,
	DEPRECATED:
	addon_mods_paths = {[1] = <path>,},
}
engine.get_games() -> table of all games in upper format (possible in async calls)

Favorites:
engine.get_favorites(location) -> list of favorites (possible in async calls)
^ location: "local" or "online"
^ returns {
	[1] = {
	clients       = <number of clients/nil>,
	clients_max   = <maximum number of clients/nil>,
	version       = <server version/nil>,
	password      = <true/nil>,
	creative      = <true/nil>,
	damage        = <true/nil>,
	pvp           = <true/nil>,
	description   = <server description/nil>,
	name          = <server name/nil>,
	address       = <address of server/nil>,
	port          = <port>
	},
}
engine.delete_favorite(id, location) -> success

Logging:
engine.debug(line) (possible in async calls)
^ Always printed to stderr and logfile (print() is redirected here)
engine.log(line) (possible in async calls)
engine.log(loglevel, line) (possible in async calls)
^ loglevel one of "error", "action", "info", "verbose"

Settings:
engine.setting_set(name, value)
engine.setting_get(name) -> string or nil (possible in async calls)
engine.setting_setbool(name, value)
engine.setting_getbool(name) -> bool or nil (possible in async calls)
engine.setting_save() -> nil, save all settings to config file

Worlds:
engine.get_worlds() -> list of worlds (possible in async calls)
^ returns {
	[1] = {
	path   = <full path to world>,
	name   = <name of world>,
	gameid = <gameid of world>,
	},
}
engine.create_world(worldname, gameid)
engine.delete_world(index)

Helpers:
engine.gettext(string) -> string
^ look up the translation of a string in the gettext message catalog
fgettext(string, ...) -> string
^ call engine.gettext(string), replace "$1"..."$9" with the given
^ extra arguments, call engine.formspec_escape and return the result
engine.parse_json(string[, nullvalue]) -> something (possible in async calls)
^ see minetest.parse_json (lua_api.txt)
dump(obj, dumped={})
^ Return object serialized as a string
string:split(separator)
^ eg. string:split("a,b", ",") == {"a","b"}
string:trim()
^ eg. string.trim("\n \t\tfoo bar\t ") == "foo bar"
minetest.is_yes(arg) (possible in async calls)
^ returns whether arg can be interpreted as yes

Async:
engine.handle_async(async_job,parameters,finished)
^ execute a function asynchronously
^ async_job is a function receiving one parameter and returning one parameter
^ parameters parameter table passed to async_job
^ finished function to be called once async_job has finished 
^    the result of async_job is passed to this function

Limitations of Async operations
 -No access to global lua variables, don't even try
 -Limited set of available functions
	e.g. No access to functions modifying menu like engine.start,engine.close,
	engine.file_open_dialog
			

Class reference
----------------
Settings: see lua_api.txt