Respect protection in MVPS (#466)

mesecons_movestones/init.lua

@@ -43,10 +43,16 @@ function mesecon.register_movestone(name, def, is_sticky, is_vertical)
 	local function movestone_move(pos, node, rulename)
 		local direction = get_movestone_direction(rulename, is_vertical)
 		local frontpos = vector.add(pos, direction)
+		local meta = minetest.get_meta(pos)
+		local owner = meta:get_string("owner")
 
 		-- ### Step 1: Push nodes in front ###
-		local success, stack, oldstack = mesecon.mvps_push(frontpos, direction, max_push)
+		local success, stack, oldstack = mesecon.mvps_push(frontpos, direction, max_push, owner)
 		if not success then
+			if stack == "protected" then
+				meta:set_string("infotext", "Can't move: protected area on the way")
+				return
+			end
 			minetest.get_node_timer(pos):start(timer_interval)
 			return
 		end
@@ -54,6 +60,8 @@ function mesecon.register_movestone(name, def, is_sticky, is_vertical)
 
 		-- ### Step 2: Move the movestone ###
 		minetest.set_node(frontpos, node)
+		local meta2 = minetest.get_meta(frontpos)
+		meta2:set_string("owner", owner)
 		minetest.remove_node(pos)
 		mesecon.on_dignode(pos, node)
 		mesecon.on_placenode(frontpos, node)
@@ -62,7 +70,7 @@ function mesecon.register_movestone(name, def, is_sticky, is_vertical)
 		-- ### Step 3: If sticky, pull stack behind ###
 		if is_sticky then
 			local backpos = vector.subtract(pos, direction)
-			success, stack, oldstack = mesecon.mvps_pull_all(backpos, direction, max_pull)
+			success, stack, oldstack = mesecon.mvps_pull_all(backpos, direction, max_pull, owner)
 			if success then
 				mesecon.mvps_move_objects(backpos, vector.multiply(direction, -1), oldstack, -1)
 			end
@@ -83,6 +91,16 @@ function mesecon.register_movestone(name, def, is_sticky, is_vertical)
 		rules = mesecon.rules.default,
 	}}
 
+	def.after_place_node = mesecon.mvps_set_owner
+
+	def.on_punch = function(pos, node, player)
+		local player_name = player and player.get_player_name and player:get_player_name()
+		if mesecon.mvps_claim(pos, player_name) then
+			minetest.get_node_timer(pos):start(timer_interval)
+			minetest.chat_send_player(player_name, "Reclaimed movestone")
+		end
+	end
+
 	def.on_timer = function(pos, elapsed)
 		local sourcepos = mesecon.is_powered(pos)
 		if not sourcepos then

mesecons_mvps/init.lua

@@ -133,31 +133,100 @@ function mesecon.mvps_get_stack(pos, dir, maximum, all_pull_sticky)
 	return nodes
 end
 
-function mesecon.mvps_push(pos, dir, maximum)
+function mesecon.mvps_set_owner(pos, placer)
-	return mesecon.mvps_push_or_pull(pos, dir, dir, maximum)
+	local meta = minetest.get_meta(pos)
+	local owner = placer and placer.get_player_name and placer:get_player_name()
+	if owner and owner ~= "" then
+		meta:set_string("owner", owner)
+	else
+		meta:set_string("owner", "$unknown") -- to distinguish from older pistons
+	end
 end
 
-function mesecon.mvps_pull_all(pos, dir, maximum)
+function mesecon.mvps_claim(pos, player_name)
-	return mesecon.mvps_push_or_pull(pos, vector.multiply(dir, -1), dir, maximum, true)
+	if not player_name or player_name == "" then return end
+	local meta = minetest.get_meta(pos)
+	if meta:get_string("infotext") == "" then return end
+	if meta:get_string("owner") == player_name then return end -- already owned
+	if minetest.is_protected(pos, player_name) then
+		minetest.chat_send_player(player_name, "Can't reclaim: protected")
+		return
+	end
+	meta:set_string("owner", player_name)
+	meta:set_string("infotext", "")
+	return true
 end
 
-function mesecon.mvps_pull_single(pos, dir, maximum)
+local function add_pos(positions, pos)
-	return mesecon.mvps_push_or_pull(pos, vector.multiply(dir, -1), dir, maximum)
+	local hash = minetest.hash_node_position(pos)
+	positions[hash] = pos
 end
 
--- pos: pos of mvps; stackdir: direction of building the stack
+local function are_protected(positions, player_name)
+	local mode = mesecon.setting("mvps_protection_mode", "normal")
+	if mode == "ignore" then
+		return false
+	end
+	local name = player_name
+	if player_name == "" or not player_name then -- legacy MVPS
+		if mode == "normal" then
+			name = "$unknown" -- sentinel, for checking for *any* protection
+		elseif mode == "compat" then
+			return false
+		elseif mode == "restrict" then
+			return true
+		else
+			error("Invalid protection mode")
+		end
+	end
+	local is_protected = minetest.is_protected
+	for _, pos in pairs(positions) do
+		if is_protected(pos, name) then
+			return true
+		end
+	end
+	return false
+end
+
+function mesecon.mvps_push(pos, dir, maximum, player_name)
+	return mesecon.mvps_push_or_pull(pos, dir, dir, maximum, false, player_name)
+end
+
+function mesecon.mvps_pull_all(pos, dir, maximum, player_name)
+	return mesecon.mvps_push_or_pull(pos, vector.multiply(dir, -1), dir, maximum, true, player_name)
+end
+
+function mesecon.mvps_pull_single(pos, dir, maximum, player_name)
+	return mesecon.mvps_push_or_pull(pos, vector.multiply(dir, -1), dir, maximum, false, player_name)
+end
+
+-- pos: pos of mvps
+-- stackdir: direction of building the stack
 -- movedir: direction of actual movement
 -- maximum: maximum nodes to be pushed
 -- all_pull_sticky: All nodes are sticky in the direction that they are pulled from
-function mesecon.mvps_push_or_pull(pos, stackdir, movedir, maximum, all_pull_sticky)
+-- player_name: Player responsible for the action.
+--  - empty string means legacy MVPS, actual check depends on configuration
+--  - "$unknown" is a sentinel for forcing the check
+function mesecon.mvps_push_or_pull(pos, stackdir, movedir, maximum, all_pull_sticky, player_name)
 	local nodes = mesecon.mvps_get_stack(pos, movedir, maximum, all_pull_sticky)
 
 	if not nodes then return end
+
+	local protection_check_set = {}
+	if vector.equals(stackdir, movedir) then -- pushing
+		add_pos(protection_check_set, pos)
+	end
 	-- determine if one of the nodes blocks the push / pull
 	for id, n in ipairs(nodes) do
 		if mesecon.is_mvps_stopper(n.node, movedir, nodes, id) then
 			return
 		end
+		add_pos(protection_check_set, n.pos)
+		add_pos(protection_check_set, vector.add(n.pos, movedir))
+	end
+	if are_protected(protection_check_set, player_name) then
+		return false, "protected"
 	end
 
 	-- remove all nodes

mesecons_pistons/init.lua

@@ -86,11 +86,15 @@ local piston_on = function(pos, node)
 	local pistonspec = get_pistonspec(node.name, "offname")
 	local dir = vector.multiply(minetest.facedir_to_dir(node.param2), -1)
 	local pusher_pos = vector.add(pos, dir)
-	local success, stack, oldstack = mesecon.mvps_push(pusher_pos, dir, max_push)
+	local meta = minetest.get_meta(pos)
+	local success, stack, oldstack = mesecon.mvps_push(pusher_pos, dir, max_push, meta:get_string("owner"))
 	if not success then
+		if stack == "protected" then
+			meta:set_string("infotext", "Can't extend: protected area on the way")
+		end
 		return
 	end
-	minetest.set_node(pos, {param2 = node.param2, name = pistonspec.onname})
+	minetest.swap_node(pos, {param2 = node.param2, name = pistonspec.onname})
 	minetest.set_node(pusher_pos, {param2 = node.param2, name = pistonspec.pusher})
 	minetest.sound_play("piston_extend", {
 		pos = pos,
@@ -103,15 +107,16 @@ end
 
 local function piston_off(pos, node)
 	local pistonspec = get_pistonspec(node.name, "onname")
-	minetest.set_node(pos, {param2 = node.param2, name = pistonspec.offname})
+	minetest.swap_node(pos, {param2 = node.param2, name = pistonspec.offname})
-	piston_remove_pusher(pos, node, not pistonspec.sticky)
+	piston_remove_pusher(pos, node, not pistonspec.sticky) -- allow that even in protected area
 
 	if not pistonspec.sticky then
 		return
 	end
 	local dir = minetest.facedir_to_dir(node.param2)
 	local pullpos = vector.add(pos, vector.multiply(dir, -2))
-	local success, stack, oldstack = mesecon.mvps_pull_single(pullpos, dir, max_pull)
+	local meta = minetest.get_meta(pos)
+	local success, stack, oldstack = mesecon.mvps_pull_single(pullpos, dir, max_pull, meta:get_string("owner"))
 	if success then
 		mesecon.mvps_move_objects(pullpos, vector.multiply(dir, -1), oldstack, -1)
 	end
@@ -125,6 +130,7 @@ local orientations = {
 }
 
 local function piston_orientate(pos, placer)
+	mesecon.mvps_set_owner(pos, placer)
 	if not placer then
 		return
 	end
@@ -237,6 +243,13 @@ local function piston_rotate_pusher(pos, node, player, mode)
 	return piston_rotate_on(piston_pos, piston_node, player, mode)
 end
 
+local function piston_punch(pos, node, player)
+	local player_name = player and player.get_player_name and player:get_player_name()
+	if mesecon.mvps_claim(pos, player_name) then
+		minetest.chat_send_player(player_name, "Reclaimed piston")
+	end
+end
+
 
 -- Boxes:
 
@@ -279,6 +292,7 @@ minetest.register_node("mesecons_pistons:piston_normal_off", {
 		action_on = piston_on,
 		rules = piston_get_rules,
 	}},
+	on_punch = piston_punch,
 	on_rotate = piston_rotate,
 	on_blast = mesecon.on_blastnode,
 })
@@ -357,6 +371,7 @@ minetest.register_node("mesecons_pistons:piston_sticky_off", {
 		action_on = piston_on,
 		rules = piston_get_rules,
 	}},
+	on_punch = piston_punch,
 	on_rotate = piston_rotate,
 	on_blast = mesecon.on_blastnode,
 })

settingtypes.txt

@@ -28,6 +28,17 @@ mesecon.luacontroller_memsize (Controller memory limit) int 100000 10000 1000000
 # IID is ignored and at most one interrupt may be queued if this setting is enabled.
 mesecon.luacontroller_lightweight_interrupts (Lightweight interrupts) bool false
 
+[mesecons_mvps]
+
+# In pre-existing world, MVPS may not be labelled with the owner.
+# Protection handling for them is configurable.
+# - normal: allow legacy MVPS to work in unprotected areas only
+# - compat: allow legacy MVPS to work everywhere
+# - ignore: allow all MVPS to work everywhere
+# - restrict: disallow legacy MVPS
+# Note that new unowned (e.g. machine-placed) MVPS are always
+# handled as in `normal` mode.
+mesecon.mvps_protection_mode (MVPS [movestones, pistons] protection handling) enum compat normal,compat,ignore,restrict
 
 [mesecons_movestones]