Fix showing up complex images

Some complex texture strings contains [ character that needs to be escaped.
Issue found with [halloween](https://github.com/GreenXenith/halloween) preview texture on player tab page button in smart_inventory. The button was dissapeared, after this change visible again.

docs/API.md

@@ -1,5 +1,5 @@
-#Full API
-##Smartfs
+# Full API
+## Smartfs
 * smartfs( name ) - returns the form regisered with the name 'name'
 * smartfs.create( name,function ) - creates a new form and adds elements to it by running the function. Use before Minetest loads. (like minetest.register_node)
 * smartfs.element( name, data ) - creates a new element type.
@@ -10,21 +10,21 @@
 * smartfs.override_load_checks() - Allows you to use smartfs.create after the game loads. Not recommended!
 * smartfs.nodemeta_on_receive_fields(nodepos, formname, fields, sender) - on_receive_fields callback can be used in minetest.register_node for nodemeta forms
 
-##Form
+## Form
 * form:show( playername [, parameters] ) - shows the form to a player. See state.param.
 * form.name - the name of the form.
 * form:attach_to_node(nodepos, params) - Attach a form to a node meta (usable in register_node's constructor, on_placenode, or dynamically)
 
-##Supported locations
+## Supported locations
 * unified_inventory or inventory_plus plugins - assigned by smartfs.add_to_inventory() - auto-detection which inventory should be used
 * player / show_formspec() - used for form:show(player)
 * (main) inventory - assigned by smartfs.set_player_inventory()
 * nodemeta - assigned by form:attach_to_node(nodepos, params)
 * container - used internally for state:container()
 
-##State
+## State
 
-###Methods
+### Methods
 * state:size( width,height ) - sets the forms width and height.
 * state:get( name ) - gets an element by name.
 * state:show() - reshows the form to the player.
@@ -53,7 +53,7 @@
   * state:view(x,y,name) - Add a virtual container (view). element coordinates are ablsolute to the parent view
 * state:element( element_type, data ) - Semi-private, create an element with type and data.
 
-###Variables
+### Variables
 * state.players - Object to handle players connected to the formspec
   * state.players:connect(playername) - register player is viewing the formspec (should be used only by framework)
   * state.players:disconnect(playername) - remove player from active viewers (should be used only by framework)
@@ -65,9 +65,9 @@
   * state.location.player - the assigned player ("player" and "inventory" only)
   * state.location.pos - the assigned node position ("nodemeta" only)
 
-##State Elements
+## State Elements
 
-###All elements / abstract
+### All elements / abstract
 * element:setPosition( x,y ) - change the position
 * element:getPosition() - get the current position
 * element:setSize( w,h ) - set the size
@@ -80,7 +80,7 @@
 * element:setTooltip(text) - set the tooltip for the button
 * element:getTooltip() - get the current tooltip
 
-###Button
+### Button
 * element:setText( text ) - set the caption of the button
 * element:getText() - get the caption of the button
 * element:setImage( filename ) - sets the background of the button
@@ -91,26 +91,26 @@
 * element:getClose() - get the current close setting
 * element:click( func(self,state,playername) ) - specify a function to run when the button is clicked (equal to onClick)
 
-###Toggle Button
+### Toggle Button
 * element:getText() - get the text of the toggle option
 * element:setId( filename ) - sets the selected id
 * element:getId() - get the selected id
 * element:onToggle( func(self,state,playername) ) - specify a function to run when the value if toggled
 
-###Label
+### Label
 * element:setText( text ) - set the caption of the label
 * element:getText() - get the caption of the label
 
-###Image and Background
+### Image and Background
 * element:setImage( image ) - set image
 * element:getImage() - get the image
 
-###Checkbox
+### Checkbox
 * element:setValue( bool ) - set the value
 * element:getValue() - get the value
 * element:onToggle( func(self,state,playername) ) - specify a function to run when the value if toggled
 
-###Field and Text Area
+### Field and Text Area
 * element:setText( text ) - set the caption of the button
 * element:getText() - get the caption of the field
 * element:isPassword() - returns true if the field is a password field
@@ -119,7 +119,7 @@
 * element:getCloseOnEnter() - Get the field_close_on_enter value
 * element:onKeyEnter(func(self, state, playername) - process the Enter key action for this fiels
 
-###List box
+### List box
 * element:onClick( func(self,state,idx,playername) ) - function to run when listbox item idx is clicked
 * element:onDoubleClick( func(self,state,idx,playername) ) - function to run when listbox item idx is double clicked
 * element:addItem( item ) - appends and item - returns the index for the item
@@ -131,7 +131,7 @@
 * element:getSelected() - get selected item (index)
 * element:getSelectedItem() - get selected item (value)
 
-###Drop Down list
+### Drop Down list
 * element:onSelect( func(self,state,field,playername) ) - function to run when dropdown entry selected
 * element:addItem( item ) - appends and item
 * element:removeItem( idx ) - remove item
@@ -142,7 +142,7 @@
 * element:getSelected() - get selected item (index)
 * element:getSelectedItem() - get selected item (value)
 
-###Inventory listing
+### Inventory listing
 * element:setLocation( location ) - set a custom inventory location or nil for the default (current_player)
   * element:usePosition( position ) - use a node metadata attached inventory of the node at the given positon
   * element:useDetached( name ) - use a detached inventory with the given name
@@ -151,11 +151,11 @@
 * element:setIndex( index ) - set the inventory starting index
 * element:getIndex() - returns the inventory starting index
 
-###Custom Code
+### Custom Code
 * element:onSubmit( func(self) ) - on form submit
 * element:onBuild( func(self) ) - run every time form is shown. You can set code from here
 * element:setCode( code ) - set the formspec code
 * element:getCode( code ) - get the formspec code
 
-###Container/View
+### Container/View
 * element:getContainerState() - returns the container's sub-state to work with or add container elements

smartfs.lua

@@ -187,7 +187,9 @@ smartfs._ldef.player = {
 					minetest.after(0, function(state)
 						if state then
 							state._show_queued = nil
-							minetest.show_formspec(state.location.player, state.def.name, state:_buildFormspec_(true))
+							if (not state.closed) and (not state.obsolete) then
+								minetest.show_formspec(state.location.player, state.def.name, state:_buildFormspec_(true))
+							end
 						end
 					end, state) -- state given as reference. Maybe additional updates are done in the meantime or the form is obsolete
 				end
@@ -213,6 +215,7 @@ smartfs._ldef.inventory = {
 		end)
 		minetest.register_on_leaveplayer(function(player)
 			local name = player:get_player_name()
+			smartfs.inv[name].obsolete = true
 			smartfs.inv[name] = nil
 		end)
 	end,
@@ -252,6 +255,7 @@ smartfs._ldef.nodemeta = {
 							local meta = minetest.get_meta(state.location.pos)
 							meta:set_string("formspec", state:_buildFormspec_(true))
 							meta:set_string("smartfs_name", state.def.name)
+							meta:mark_as_private("smartfs_name")
 						end
 					end, state)
 				end
@@ -293,9 +297,13 @@ function smartfs.nodemeta_on_receive_fields(nodepos, formname, fields, sender, p
 	local state
 	local form = smartfs.get(nodeform)
 	if not smartfs.opened[opened_id] or      -- If opened first time
-			smartfs.opened[opened_id].def.name ~= nodeform then -- Or form is changed
+			smartfs.opened[opened_id].def.name ~= nodeform or -- Or form is changed
+			smartfs.opened[opened_id].obsolete then
 		local statelocation = smartfs._ldef.nodemeta._make_state_location_(nodepos)
 		state = smartfs._makeState_(form, params, statelocation)
+		if smartfs.opened[opened_id] then
+			smartfs.opened[opened_id].obsolete = true
+		end
 		smartfs.opened[opened_id] = state
 		form.form_setup_callback(state)
 	else
@@ -313,7 +321,7 @@ function smartfs.nodemeta_on_receive_fields(nodepos, formname, fields, sender, p
 	state:_sfs_on_receive_fields_(name, fields)
 
 	-- Reset form if all players disconnected
-	if sender and not state.players:get_first() then
+	if sender and not state.players:get_first() and not state.obsolete then
 		local statelocation = smartfs._ldef.nodemeta._make_state_location_(nodepos)
 		local resetstate = smartfs._makeState_(form, params, statelocation)
 		if form.form_setup_callback(resetstate) ~= false then
@@ -331,9 +339,13 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 	if smartfs.opened[name] and smartfs.opened[name].location.type == "player" then
 		if smartfs.opened[name].def.name == formname then
 			local state = smartfs.opened[name]
-			return state:_sfs_on_receive_fields_(name, fields)
-		else
-			smartfs.opened[name] = nil
+			state:_sfs_on_receive_fields_(name, fields)
+
+			-- disconnect player if form closed
+			if not state.players:get_first() then
+				smartfs.opened[name].obsolete = true
+				smartfs.opened[name] = nil
+			end
 		end
 	elseif smartfs.inv[name] and smartfs.inv[name].location.type == "inventory" then
 		local state = smartfs.inv[name]
@@ -359,6 +371,9 @@ function smartfs._show_(form, name, params)
 	local statelocation = smartfs._ldef.player._make_state_location_(name)
 	local state = smartfs._makeState_(form, params, statelocation, name)
 	if form.form_setup_callback(state) ~= false then
+		if smartfs.opened[name] then -- set maybe previous form to obsolete
+			smartfs.opened[name].obsolete = true
+		end
 		smartfs.opened[name] = state
 		state:show()
 	end
@@ -375,6 +390,10 @@ function smartfs._attach_to_node_(form, nodepos, params)
 	local statelocation = smartfs._ldef.nodemeta._make_state_location_(nodepos)
 	local state = smartfs._makeState_(form, params, statelocation)
 	if form.form_setup_callback(state) ~= false then
+		local opened_id = minetest.pos_to_string(nodepos)
+		if smartfs.opened[opened_id] then -- set maybe previous form to obsolete
+			smartfs.opened[opened_id].obsolete = true
+		end
 		state:show()
 	end
 	return state
@@ -517,14 +536,11 @@ function smartfs._makeState_(form, params, location, newplayer)
 				end
 			end
 
-			if not fields.quit and not self.closed then
+			if not fields.quit and not self.closed and not self.obsolete then
 				self:show()
 			else
 				self.players:disconnect(player)
-				if self.location.type == "player" then
-					smartfs.opened[player] = nil
-				end
-				if not fields.quit and self.closed then
+				if not fields.quit and self.closed and not self.obsolete then
 					--closed by application (without fields.quit). currently not supported, see: https://github.com/minetest/minetest/pull/4675
 					minetest.show_formspec(player,"","size[5,1]label[0,0;Formspec closing not yet created!]")
 				end
@@ -869,7 +885,7 @@ smartfs.element("button", {
 				self.data.pos.x..","..self.data.pos.y..";"..
 				self.data.size.w..","..self.data.size.h..";"
 		if self.data.image then
-			specstring = specstring..self.data.image..";"
+			specstring = specstring..minetest.formspec_escape(self.data.image)..";"
 		elseif self.data.item then
 			specstring = specstring..self.data.item..";"
 		end
@@ -1080,7 +1096,7 @@ smartfs.element("image", {
 				";"..
 				self.data.size.w..","..self.data.size.h..
 				";"..
-				self.data.value..
+				minetest.formspec_escape(self.data.value)..
 				"]"
 		else
 			return "image["..
@@ -1088,7 +1104,7 @@ smartfs.element("image", {
 				";"..
 				self.data.size.w..","..self.data.size.h..
 				";"..
-				self.data.value..
+				minetest.formspec_escape(self.data.value)..
 				"]"
 		end
 	end,
@@ -1299,7 +1315,7 @@ smartfs.element("inventory", {
 	end,
 	build = function(self)
 		return "list["..
-			(self.data.location or "current_player") ..
+			(self.data.invlocation or "current_player") ..
 			";"..
 			self.name..    --no namespacing
 			";"..
@@ -1316,20 +1332,20 @@ smartfs.element("inventory", {
 	-- "nodemeta:<X>,<Y>,<Z>": Any node metadata
 	-- "detached:<name>": A detached inventory
 	-- "context" does not apply to smartfs, since there is no node-metadata as context available
-	setLocation = function(self,location)
-		self.data.location = location
+	setLocation = function(self,invlocation)
+		self.data.invlocation = invlocation
 	end,
 	getLocation = function(self)
-		return self.data.location or "current_player"
+		return self.data.invlocation or "current_player"
 	end,
 	usePosition = function(self, pos)
-		self.data.location = string.format("nodemeta:%d,%d,%d", pos.x, pos.y, pos.z)
+		self.data.invlocation = string.format("nodemeta:%d,%d,%d", pos.x, pos.y, pos.z)
 	end,
 	usePlayer = function(self, name)
-		self.data.location = "player:" .. name
+		self.data.invlocation = "player:" .. name
 	end,
 	useDetached = function(self, name)
-		self.data.location = "detached:" .. name
+		self.data.invlocation = "detached:" .. name
 	end,
 	setIndex = function(self,index)
 		self.data.index = index