Mainmenu: Refactor tab UI code

- Use local variables for tabs in place of globals
 - Merge together if statements where possible
 - Replace manual table searching code with indexof where possible

builtin/mainmenu/init.lua

@@ -37,23 +37,29 @@ dofile(menupath .. DIR_DELIM .. "common.lua")
 dofile(menupath .. DIR_DELIM .. "gamemgr.lua")
 dofile(menupath .. DIR_DELIM .. "modmgr.lua")
 dofile(menupath .. DIR_DELIM .. "store.lua")
+dofile(menupath .. DIR_DELIM .. "textures.lua")
+
 dofile(menupath .. DIR_DELIM .. "dlg_config_world.lua")
-dofile(menupath .. DIR_DELIM .. "tab_credits.lua")
-dofile(menupath .. DIR_DELIM .. "tab_mods.lua")
-dofile(menupath .. DIR_DELIM .. "tab_settings.lua")
 dofile(menupath .. DIR_DELIM .. "dlg_settings_advanced.lua")
 if PLATFORM ~= "Android" then
 	dofile(menupath .. DIR_DELIM .. "dlg_create_world.lua")
 	dofile(menupath .. DIR_DELIM .. "dlg_delete_mod.lua")
 	dofile(menupath .. DIR_DELIM .. "dlg_delete_world.lua")
 	dofile(menupath .. DIR_DELIM .. "dlg_rename_modpack.lua")
-	dofile(menupath .. DIR_DELIM .. "tab_multiplayer.lua")
-	dofile(menupath .. DIR_DELIM .. "tab_server.lua")
-	dofile(menupath .. DIR_DELIM .. "tab_singleplayer.lua")
-	dofile(menupath .. DIR_DELIM .. "tab_texturepacks.lua")
-	dofile(menupath .. DIR_DELIM .. "textures.lua")
+end
+
+local tabs = {}
+
+tabs.settings = dofile(menupath .. DIR_DELIM .. "tab_settings.lua")
+tabs.mods = dofile(menupath .. DIR_DELIM .. "tab_mods.lua")
+tabs.credits = dofile(menupath .. DIR_DELIM .. "tab_credits.lua")
+if PLATFORM == "Android" then
+	tabs.simple_main = dofile(menupath .. DIR_DELIM .. "tab_simple_main.lua")
 else
-	dofile(menupath .. DIR_DELIM .. "tab_simple_main.lua")
+	tabs.singleplayer = dofile(menupath .. DIR_DELIM .. "tab_singleplayer.lua")
+	tabs.multiplayer = dofile(menupath .. DIR_DELIM .. "tab_multiplayer.lua")
+	tabs.server = dofile(menupath .. DIR_DELIM .. "tab_server.lua")
+	tabs.texturepacks = dofile(menupath .. DIR_DELIM .. "tab_texturepacks.lua")
 end
 
 --------------------------------------------------------------------------------
@@ -69,8 +75,19 @@ local function init_globals()
 	-- Init gamedata
 	gamedata.worldindex = 0
 
+	if PLATFORM == "Android" then
+		local world_list = core.get_worlds()
+		local world_index = table.indexof(world_list, "singleplayerworld")
 
-	if PLATFORM ~= "Android" then
+		if world_index == -1 then
+			core.create_world("singleplayerworld", 1)
+
+			world_list = core.get_worlds()
+			world_index = table.indexof(world_list, "singleplayerworld")
+		end
+
+		gamedata.worldindex = world_index
+	else
 		menudata.worldlist = filterlist.create(
 			core.get_worlds,
 			compare_worlds,
@@ -93,57 +110,30 @@ local function init_globals()
 		end
 
 		mm_texture.init()
-	else
-		local world_list = core.get_worlds()
-
-		local found_singleplayerworld = false
-
-		for i,world in pairs(world_list) do
-			if world.name == "singleplayerworld" then
-				found_singleplayerworld = true
-				gamedata.worldindex = i
-				break
-			end
-		end
-
-		if not found_singleplayerworld then
-			core.create_world("singleplayerworld", 1)
-
-			local world_list = core.get_worlds()
-
-			for i,world in pairs(world_list) do
-				if world.name == "singleplayerworld" then
-					gamedata.worldindex = i
-					break
-				end
-			end
-		end
 	end
 
 	-- Create main tabview
 	local tv_main = tabview_create("maintab", {x = 12, y = 5.2}, {x = 0, y = 0})
-	if PLATFORM ~= "Android" then
-		tv_main:set_autosave_tab(true)
-	end
-	if PLATFORM ~= "Android" then
-		tv_main:add(tab_singleplayer)
-		tv_main:add(tab_multiplayer)
-		tv_main:add(tab_server)
+
+	if PLATFORM == "Android" then
+		tv_main:add(tabs.simple_main)
+		tv_main:add(tabs.settings)
 	else
-		tv_main:add(tab_simple_main)
+		tv_main:set_autosave_tab(true)
+		tv_main:add(tabs.singleplayer)
+		tv_main:add(tabs.multiplayer)
+		tv_main:add(tabs.server)
+		tv_main:add(tabs.settings)
+		tv_main:add(tabs.texturepacks)
 	end
-	tv_main:add(tab_settings)
-	if PLATFORM ~= "Android" then
-		tv_main:add(tab_texturepacks)
-	end
-	tv_main:add(tab_mods)
-	tv_main:add(tab_credits)
+
+	tv_main:add(tabs.mods)
+	tv_main:add(tabs.credits)
 
 	tv_main:set_global_event_handler(main_event_handler)
-
 	tv_main:set_fixed_size(false)
 
-	if not (PLATFORM == "Android") then
+	if PLATFORM ~= "Android" then
 		tv_main:set_tab(core.setting_get("maintab_LAST"))
 	end
 	ui.set_default("maintab")

builtin/mainmenu/tab_credits.lua

@@ -69,7 +69,7 @@ local previous_contributors = {
 	"Zefram <zefram@fysh.org>",
 }
 
-tab_credits = {
+return {
 	name = "credits",
 	caption = fgettext("Credits"),
 	cbf_formspec = function(tabview, name, tabdata)

builtin/mainmenu/tab_mods.lua

@@ -163,7 +163,7 @@ local function handle_buttons(tabview, fields, tabname, tabdata)
 end
 
 --------------------------------------------------------------------------------
-tab_mods = {
+return {
 	name = "mods",
 	caption = fgettext("Mods"),
 	cbf_formspec = get_formspec,

builtin/mainmenu/tab_multiplayer.lua

@@ -256,7 +256,7 @@ local function on_change(type,old_tab,new_tab)
 end
 
 --------------------------------------------------------------------------------
-tab_multiplayer = {
+return {
 	name = "multiplayer",
 	caption = fgettext("Client"),
 	cbf_formspec = get_formspec,

builtin/mainmenu/tab_server.lua

@@ -186,7 +186,7 @@ local function main_button_handler(this, fields, name, tabdata)
 end
 
 --------------------------------------------------------------------------------
-tab_server = {
+return {
 	name = "server",
 	caption = fgettext("Server"),
 	cbf_formspec = get_formspec,

builtin/mainmenu/tab_settings.lua

@@ -384,7 +384,7 @@ local function handle_settings_buttons(this, fields, tabname, tabdata)
 	return ddhandled
 end
 
-tab_settings = {
+return {
 	name = "settings",
 	caption = fgettext("Settings"),
 	cbf_formspec = formspec,

builtin/mainmenu/tab_simple_main.lua

@@ -196,7 +196,7 @@ local function on_activate(type,old_tab,new_tab)
 end
 
 --------------------------------------------------------------------------------
-tab_simple_main = {
+return {
 	name = "main",
 	caption = fgettext("Main"),
 	cbf_formspec = get_formspec,

builtin/mainmenu/tab_singleplayer.lua

@@ -241,7 +241,7 @@ local function on_change(type, old_tab, new_tab)
 end
 
 --------------------------------------------------------------------------------
-tab_singleplayer = {
+return {
 	name = "singleplayer",
 	caption = fgettext("Singleplayer"),
 	cbf_formspec = get_formspec,

builtin/mainmenu/tab_texturepacks.lua

@@ -123,7 +123,7 @@ local function main_button_handler(tabview, fields, name, tabdata)
 end
 
 --------------------------------------------------------------------------------
-tab_texturepacks = {
+return {
 	name = "texturepacks",
 	caption = fgettext("Texturepacks"),
 	cbf_formspec = get_formspec,