Make mesechest more reliable (#35)

The current hack to get on the `on_player_receive_fields` function is quite likely to break with instrumented code.
This also changes the workaround to get custom inventory callbacks by using `minetest.override_item`.

.luacheckrc

@@ -1,22 +1,9 @@
 read_globals = {
 	-- Defined by Minetest
-	"vector", "PseudoRandom", "VoxelArea", "table",
+	"minetest", "vector", "PseudoRandom", "VoxelArea", "table",
 
 	-- Mods
 	"digiline", "default", "creative",
-
-	-- Required for the mesechest registration
-	minetest = {
-		fields = {
-			register_lbm = {read_only = false},
-			register_node = {read_only = false},
-			registered_on_player_receive_fields = {
-				read_only = false,
-				other_fields = true,
-			},
-		},
-		other_fields = true
-	}
 }
 globals = {"moremesecons", "mesecon"}
 ignore = {"212", "631", "422", "432"}

moremesecons_mesechest/init.lua

@@ -8,59 +8,8 @@ local function mesechest_get_output_rules(node)
 	return rules
 end
 
-
+-- default.chest.register_chest() doesn't allow to register most of the callbacks we need
-local open_chests = {}
+-- we have to override the chest node we registered again
-
--- Override minetest.register_node so it adds a prefix ":"
-local old_minetest_register_node = minetest.register_node
-minetest.register_node = function(name, def)
-	local old_on_metadata_inventory_put = def.on_metadata_inventory_put
-	local old_on_metadata_inventory_take = def.on_metadata_inventory_take
-	local old_on_rightclick = def.on_rightclick
-
-	def.on_metadata_inventory_put = function(pos, ...)
-		old_on_metadata_inventory_put(pos, ...)
-		mesecon.receptor_on(pos, {mesechest_get_output_rules(minetest.get_node(pos))[2]})
-		minetest.after(1, function(pos)
-			mesecon.receptor_off(pos, {mesechest_get_output_rules(minetest.get_node(pos))[2]})
-		end, pos)
-	end
-	def.on_metadata_inventory_take = function(pos, ...)
-		old_on_metadata_inventory_take(pos, ...)
-		mesecon.receptor_on(pos, {mesechest_get_output_rules(minetest.get_node(pos))[3]})
-		minetest.after(1, function(pos)
-			mesecon.receptor_off(pos, {mesechest_get_output_rules(minetest.get_node(pos))[3]})
-		end, pos)
-	end
-	def.on_rightclick = function(pos, node, clicker, ...)
-		if old_on_rightclick(pos, node, clicker, ...) == nil then
-			mesecon.receptor_on(pos, {mesechest_get_output_rules(node)[1]})
-			open_chests[clicker:get_player_name()] = pos
-		end
-	end
-
-	old_minetest_register_node(":"..name, def)
-end
-local old_minetest_register_lbm = minetest.register_lbm
-minetest.register_lbm = function() end
-
--- Get the on_player_receive_fields function. That's a huge hack
-for i, f in ipairs(minetest.registered_on_player_receive_fields) do
-	local serialized = minetest.serialize(f)
-	if string.find(serialized, "default:chest") then
-		minetest.registered_on_player_receive_fields[i] = function(player, formname, fields)
-			if f(player, formname, fields) == true then
-				local pn = player:get_player_name()
-				if open_chests[pn] then
-					mesecon.receptor_off(open_chests[pn], {mesechest_get_output_rules(minetest.get_node(open_chests[pn]))[1]})
-					open_chests[pn] = nil
-				end
-			end
-		end
-		break
-	end
-end
-
 default.chest.register_chest("moremesecons_mesechest:mesechest", {
 	description = "Mese Chest",
 	tiles = {
@@ -104,8 +53,55 @@ default.chest.register_chest("moremesecons_mesechest:mesechest_locked", {
 	}
 })
 
-minetest.register_node = old_minetest_register_node
+local moremesecons_chests = {}
-minetest.register_lbm = old_minetest_register_lbm
+
+for _, chest in ipairs({"moremesecons_mesechest:mesechest", "moremesecons_mesechest:mesechest_locked",
+						"moremesecons_mesechest:mesechest_open", "moremesecons_mesechest:mesechest_locked_open"}) do
+	local old_def = minetest.registered_nodes[chest]
+
+	local old_on_metadata_inventory_put = old_def.on_metadata_inventory_put
+	local old_on_metadata_inventory_take = old_def.on_metadata_inventory_take
+	local old_on_rightclick = old_def.on_rightclick
+
+	local override = {}
+	override.on_metadata_inventory_put = function(pos, ...)
+		old_on_metadata_inventory_put(pos, ...)
+		mesecon.receptor_on(pos, {mesechest_get_output_rules(minetest.get_node(pos))[2]})
+		minetest.after(1, function(pos)
+			mesecon.receptor_off(pos, {mesechest_get_output_rules(minetest.get_node(pos))[2]})
+		end, pos)
+	end
+	override.on_metadata_inventory_take = function(pos, ...)
+		old_on_metadata_inventory_take(pos, ...)
+		mesecon.receptor_on(pos, {mesechest_get_output_rules(minetest.get_node(pos))[3]})
+		minetest.after(1, function(pos)
+			mesecon.receptor_off(pos, {mesechest_get_output_rules(minetest.get_node(pos))[3]})
+		end, pos)
+	end
+	override.on_rightclick = function(pos, node, clicker, ...)
+		if old_on_rightclick(pos, node, clicker, ...) == nil then
+			mesecon.receptor_on(pos, {mesechest_get_output_rules(node)[1]})
+		end
+	end
+
+	minetest.override_item(chest, override)
+	moremesecons_chests[chest] = true
+end
+
+-- if the chest is getting closed, turn the signal off
+-- luacheck: ignore 122
+local old_lid_close = default.chest.chest_lid_close
+function default.chest.chest_lid_close(pn)
+	local pos = default.chest.open_chests[pn].pos
+	-- old_lid_close will return true if the chest won't be closed
+	if old_lid_close(pn) then
+		return true
+	end
+	local node = minetest.get_node(pos)
+	if moremesecons_chests[node.name] then
+		mesecon.receptor_off(pos, {mesechest_get_output_rules(node)[1]})
+	end
+end
 
 minetest.register_craft({
 	output = "moremesecons_mesechest:mesechest",