Add formspec toolkit and refactor mainmenu to use it

Fix crash on using cursor keys in client menu without selected server
Add support for non fixed size tabviews

2 files changed, 225 insertions, 54 deletions

diff --git a/doc/fst_api.txt b/doc/fst_api.txt
new file mode 100644
index 000000000..54f2d07a6
--- /dev/null
+++ b/doc/fst_api.txt
@@ -0,0 +1,171 @@
+Formspec toolkit api 0.0.3
+==========================
+
+Formspec toolkit is a set of functions to create basic ui elements.
+
+
+File: fst/ui.lua
+----------------
+
+ui.lua adds base ui interface to add additional components to.
+
+ui.add(component) -> returns name of added component
+^ add component to ui
+^ component: component to add
+
+ui.delete(component) -> true/false if a component was deleted or not
+^ remove a component from ui
+^ component: component to delete
+
+ui.set_default(name)
+^ set component to show if not a single component is set visible
+^ name: name of component to set as default
+
+ui.find_by_name(name) --> returns component or nil
+^ find a component within ui
+^ name: name of component to look for
+
+File: fst/tabview.lua
+---------------------
+
+tabview_create(name, size, tabheaderpos) --> returns tabview component
+^ create a new tabview component
+^ name: name of tabview (has to be unique per ui)
+^ size: size of tabview
+	{
+		x,
+		y
+	}
+^ tabheaderpos: upper left position of tabheader (relative to upper left fs corner)
+	{
+		x,
+		y
+	}
+
+Class reference tabview:
+
+methods:
+- add_tab(tab)
+  ^ add a tab to this tabview
+  ^ tab:
+  {
+	name               = "tabname",      -- name of tab to create
+	caption            = "tab caption",  -- text to show for tab header
+	cbf_button_handler = function(tabview, fields, tabname, tabdata), -- callback for button events
+	--TODO cbf_events         = function(tabview, event, tabname),           -- callback for events
+	cbf_formspec       = function(tabview, name, tabdata),            -- get formspec
+	tabsize            =
+		{
+			x, -- x width
+			y  -- y height
+		},                                                            -- special size for this tab (only relevant if no parent for tabview set)
+	on_change          = function(type,old_tab,new_tab)               -- called on tab chang, type is "ENTER" or "LEAVE"
+  }
+- set_autosave_tab(value)
+  ^ tell tabview to automaticaly save current tabname as "tabview_name"_LAST
+  ^ value: true/false
+- set_tab(name)
+  ^ set's tab to tab named "name", returns true/false on success
+  ^ name: name of tab to set
+- set_global_event_handler(handler)
+  ^ set a handler to be called prior calling tab specific event handler
+  ^ handler: function(tabview,event) --> returns true to finish event processing false to continue
+- set_global_button_handler(handler)
+  ^ set a handler to be called prior calling tab specific button handler
+  ^ handler: function(tabview,fields) --> returns true to finish button processing false to continue
+- set_parent(parent)
+  ^ set parent to attach tabview to. TV's with parent are hidden if their parent
+	is hidden and they don't set their specified size.
+  ^ parent: component to attach to
+- show()
+  ^ show tabview
+- hide()
+  ^ hide tabview
+- delete()
+  ^ delete tabview
+- set_fixed_size(state)
+  ^ true/false set to fixed size, variable size
+
+File: fst/dialog.lua
+---------------------
+Only one dialog can be shown at a time. If a dialog is closed it's parent is
+gonna be activated and shown again.
+
+dialog_create(name, cbf_formspec, cbf_button_handler, cbf_events)
+^ create a dialog component
+^ name: name of component (unique per ui)
+^ cbf_formspec: function to be called to get formspec
+	function(dialogdata)
+^ cbf_button_handler: function to handle buttons
+	function(dialog, fields)
+^ cbf_events: function to handle events
+	function(dialog, event)
+
+Class reference dialog:
+
+methods:
+- set_parent(parent)
+  ^ set parent to attach a dialog to
+  ^ parent: component to attach to
+- show()
+  ^ show dialog
+- hide()
+  ^ hide dialog
+- delete()
+  ^ delete dialog from ui
+  
+members:
+- data
+  ^ variable data attached to this dialog
+- parent
+  ^ parent component to return to on exit
+  
+File: fst/buttonbar.lua
+-----------------------
+
+buttonbar_create(name, cbf_buttonhandler, pos, orientation, size)
+^ create a buttonbar
+^ name: name of component (unique per ui)
+^ cbf_buttonhandler: function to be called on button pressed
+	function(buttonbar,buttonname,buttondata)
+^ pos: position relative to upper left of current shown formspec
+	{
+		x,
+		y
+	}
+^ orientation: "vertical" or "horizontal"
+^ size: size of bar
+	{
+		width,
+		height
+	}
+
+Class reference buttonbar:
+
+methods:
+- add_button(btn_id, caption, button_image)
+- set_parent(parent)
+  ^ set parent to attach a buttonbar to
+  ^ parent: component to attach to
+- show()
+  ^ show buttonbar
+- hide()
+  ^ hide buttonbar
+- delete()
+  ^ delete buttonbar from ui
+
+Developer doc:
+==============
+Skeleton for any component:
+{
+	name           = "some id",               -- unique id
+	type           = "toplevel",              -- type of component
+	                                          -- toplevel: componant can be show without additional components
+	                                          -- addon:    component is an addon to be shown along toplevel component
+	hide           = function(this) end,      -- called to hide the component
+	show           = function(this) end,      -- called to show the component
+	delete         = function(this) end,      -- called to delete component from ui
+	handle_buttons = function(this,fields)    -- called upon button press
+	handle_events  = function(this,event)     -- called upon event reception
+	get_formspec   = function(this)           -- has to return formspec to be displayed
+}
diff --git a/doc/menu_lua_api.txt b/doc/menu_lua_api.txt
index 109aededa..cd44fa815 100644
--- a/doc/menu_lua_api.txt
+++ b/doc/menu_lua_api.txt
@@ -1,4 +1,4 @@
-Minetest Lua Mainmenu API Reference 0.4.9
+Minetest Lua Mainmenu API Reference 0.4.10
 ========================================
 
 Introduction
@@ -8,14 +8,14 @@ Description of formspec language to show your menu is in lua_api.txt
 
 Callbacks
 ---------
-engine.buttonhandler(fields): called when a button is pressed.
+core.buttonhandler(fields): called when a button is pressed.
 ^ fields = {name1 = value1, name2 = value2, ...}
-engine.event_handler(event)
+core.event_handler(event)
 ^ event: "MenuQuit", "KeyEnter", "ExitButton" or "EditBoxEnter"
 
 Gamedata
 --------
-The "gamedata" table is read when calling engine.start(). It should contain:
+The "gamedata" table is read when calling core.start(). It should contain:
 {
 	playername     = <name>,
 	password       = <password>,
@@ -27,15 +27,15 @@ The "gamedata" table is read when calling engine.start(). It should contain:
 
 Functions
 ---------
-engine.start()
-engine.close()
+core.start()
+core.close()
 
 Filesystem:
-engine.get_scriptdir()
+core.get_scriptdir()
 ^ returns directory of script
-engine.get_modpath() (possible in async calls)
+core.get_modpath() (possible in async calls)
 ^ returns path to global modpath
-engine.get_modstore_details(modid) (possible in async calls)
+core.get_modstore_details(modid) (possible in async calls)
 ^ modid numeric id of mod in modstore
 ^ returns {
 	id			= <numeric id of mod in modstore>,
@@ -47,7 +47,7 @@ engine.get_modstore_details(modid) (possible in async calls)
 	license		= <short description of license>,
 	rating		= <float value of current rating>
 }
-engine.get_modstore_list() (possible in async calls)
+core.get_modstore_list() (possible in async calls)
 ^ returns {
 	[1] = {
 		id		 = <numeric id of mod in modstore>,
@@ -55,60 +55,60 @@ engine.get_modstore_list() (possible in async calls)
 		basename = <basename for mod>
 	}
 }
-engine.get_gamepath() (possible in async calls)
+core.get_gamepath() (possible in async calls)
 ^ returns path to global gamepath
-engine.get_texturepath() (possible in async calls)
+core.get_texturepath() (possible in async calls)
 ^ returns path to default textures
-engine.get_dirlist(path,onlydirs) (possible in async calls)
+core.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)
+core.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)
+core.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)
+core.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]
+core.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)
+core.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)
+core.get_version() (possible in async calls)
 ^ returns current core version
-engine.sound_play(spec, looped) -> handle
+core.sound_play(spec, looped) -> handle
 ^ spec = SimpleSoundSpec (see lua-api.txt)
 ^ looped = bool
-engine.sound_stop(handle)
+core.sound_stop(handle)
 
 Formspec:
-engine.update_formspec(formspec)
-engine.get_table_index(tablename) -> index
+core.update_formspec(formspec)
+core.get_table_index(tablename) -> index
 ^ can also handle textlists
-engine.formspec_escape(string) -> string
+core.formspec_escape(string) -> string
 ^ escapes characters [ ] \ , ; that can not be used in formspecs
-engine.explode_table_event(string) -> table
+core.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
+core.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)
+core.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)
+core.set_clouds(<true/false>)
+core.set_topleft_text(text)
+core.show_keys_menu()
+core.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"
@@ -116,7 +116,7 @@ engine.file_open_dialog(formname,caption)
 ^     -if dialog was canceled "_cancelled"
 ^        will be added to fieldname value is set to formname itself
 ^ returns nil or selected file/folder
-engine.get_screen_info()
+core.get_screen_info()
 ^ returns {
 	density         = <screen density 0.75,1.0,2.0,3.0 ... (dpi)>,
 	display_width   = <width of display>,
@@ -126,7 +126,7 @@ engine.get_screen_info()
 	}
 
 Games:
-engine.get_game(index)
+core.get_game(index)
 ^ returns {
 	id               = <id>,
 	path             = <full path to game>,
@@ -136,10 +136,10 @@ engine.get_game(index)
 	DEPRECATED:
 	addon_mods_paths = {[1] = <path>,},
 }
-engine.get_games() -> table of all games in upper format (possible in async calls)
+core.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)
+core.get_favorites(location) -> list of favorites (possible in async calls)
 ^ location: "local" or "online"
 ^ returns {
 	[1] = {
@@ -156,24 +156,24 @@ engine.get_favorites(location) -> list of favorites (possible in async calls)
 	port          = <port>
 	},
 }
-engine.delete_favorite(id, location) -> success
+core.delete_favorite(id, location) -> success
 
 Logging:
-engine.debug(line) (possible in async calls)
+core.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)
+core.log(line) (possible in async calls)
+core.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
+core.setting_set(name, value)
+core.setting_get(name) -> string or nil (possible in async calls)
+core.setting_setbool(name, value)
+core.setting_getbool(name) -> bool or nil (possible in async calls)
+core.setting_save() -> nil, save all settings to config file
 
 Worlds:
-engine.get_worlds() -> list of worlds (possible in async calls)
+core.get_worlds() -> list of worlds (possible in async calls)
 ^ returns {
 	[1] = {
 	path   = <full path to world>,
@@ -181,16 +181,16 @@ engine.get_worlds() -> list of worlds (possible in async calls)
 	gameid = <gameid of world>,
 	},
 }
-engine.create_world(worldname, gameid)
-engine.delete_world(index)
+core.create_world(worldname, gameid)
+core.delete_world(index)
 
 Helpers:
-engine.gettext(string) -> string
+core.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)
+^ call core.gettext(string), replace "$1"..."$9" with the given
+^ extra arguments, call core.formspec_escape and return the result
+core.parse_json(string[, nullvalue]) -> something (possible in async calls)
 ^ see core.parse_json (lua_api.txt)
 dump(obj, dumped={})
 ^ Return object serialized as a string
@@ -202,7 +202,7 @@ core.is_yes(arg) (possible in async calls)
 ^ returns whether arg can be interpreted as yes
 
 Async:
-engine.handle_async(async_job,parameters,finished)
+core.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
@@ -212,8 +212,8 @@ engine.handle_async(async_job,parameters,finished)
 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
+	e.g. No access to functions modifying menu like core.start,core.close,
+	core.file_open_dialog
 			
 
 Class reference