From a960bf2e8e3da2dd4086a511f85aec97694d23c7 Mon Sep 17 00:00:00 2001
From: Dehydrate6684 <minetest.ysjbc@aleeas.com>
Date: Sat, 16 Sep 2023 13:16:49 +0800
Subject: [PATCH] Update trapdoor climbable behavior

---
 mods/ITEMS/mcl_core/nodes_climb.lua    | 48 ++++++++++++++++++++++++-
 mods/ITEMS/mcl_doors/api_trapdoors.lua | 50 +++++++++++++++++++++++---
 2 files changed, 93 insertions(+), 5 deletions(-)

diff --git a/mods/ITEMS/mcl_core/nodes_climb.lua b/mods/ITEMS/mcl_core/nodes_climb.lua
index 33a34f899..1e94a37dc 100644
--- a/mods/ITEMS/mcl_core/nodes_climb.lua
+++ b/mods/ITEMS/mcl_core/nodes_climb.lua
@@ -33,7 +33,14 @@ minetest.register_node("mcl_core:ladder", {
 		wall_side = { -0.5, -0.5, -0.5, -7/16, 0.5, 0.5 },
 	},
 	stack_max = 64,
-	groups = {handy=1,axey=1, attached_node=1, deco_block=1, dig_by_piston=1},
+	groups = {
+		handy = 1,
+		axey = 1,
+		attached_node = 1,
+		deco_block = 1,
+		dig_by_piston = 1,
+		ladder = 1
+	},
 	sounds = mcl_sounds.node_sound_wood_defaults(),
 	node_placement_prediction = "",
 	-- Restrict placement of ladders
@@ -80,7 +87,46 @@ minetest.register_node("mcl_core:ladder", {
 		end
 		return itemstack
 	end,
+	after_destruct = function(pos, oldnode)
+		local pos_above = vector.add(pos, {x = 0, y = 1, z = 0 })
+		local node_above = minetest.get_node_or_nil(pos_above)
 
+		if node_above then
+			local is_trapdoor = minetest.get_item_group(node_above.name, "trapdoor")
+
+			-- If node above is an opened trapdoor
+			if is_trapdoor == 2 then
+				local above_def = minetest.registered_nodes[node_above.name]
+				if above_def._other then
+					minetest.swap_node(pos_above, {
+										   name = above_def._other,
+										   param1 = node_above.param1,
+										   param2 = node_above.param2,
+					})
+				end
+			end
+		end
+	end,
+	after_place_node = function(pos, oldnode)
+		local pos_above = vector.add(pos, {x = 0, y = 1, z = 0 })
+		local node_above = minetest.get_node_or_nil(pos_above)
+
+		if node_above then
+			local is_trapdoor = minetest.get_item_group(node_above.name, "trapdoor")
+
+			-- If node above is an opened trapdoor
+			if is_trapdoor == 2 then
+				local above_def = minetest.registered_nodes[node_above.name]
+				if above_def._other then
+					minetest.swap_node(pos_above, {
+										   name = above_def._other,
+										   param1 = node_above.param1,
+										   param2 = node_above.param2,
+					})
+				end
+			end
+		end
+	end,
 	_mcl_blast_resistance = 0.4,
 	_mcl_hardness = 0.4,
 	on_rotate = rotate_climbable,
diff --git a/mods/ITEMS/mcl_doors/api_trapdoors.lua b/mods/ITEMS/mcl_doors/api_trapdoors.lua
index 5b7a0e5d0..c42ffd7c3 100644
--- a/mods/ITEMS/mcl_doors/api_trapdoors.lua
+++ b/mods/ITEMS/mcl_doors/api_trapdoors.lua
@@ -72,7 +72,21 @@ function mcl_doors:register_trapdoor(name, def)
 		-- Open
 		else
 			minetest.sound_play(def.sound_open, {pos = pos, gain = 0.3, max_hear_distance = 16}, true)
-			tmp_node = {name=name.."_open", param1=me.param1, param2=me.param2}
+
+			local bottom_node = minetest.get_node_or_nil(vector.subtract(pos, { x = 0, y = 1, z = 0 }))
+			local name_end = "_open"
+
+			-- Checking if there is something underneath the trapdoor
+			if bottom_node then
+				local bottom_def = minetest.registered_nodes[bottom_node.name]
+				local trapdoor = minetest.get_item_group(bottom_node.name, "trapdoor")
+
+				-- Changing trapdoor into a ladder if bottom node is climbable and not a trapdoor
+				if trapdoor ~= 2 and bottom_def.climbable then
+					name_end = "_ladder"
+				end
+			end
+			tmp_node = {name=name..name_end, param1=me.param1, param2=me.param2}
 		end
 		minetest.set_node(pos, tmp_node)
 	end
@@ -193,6 +207,7 @@ function mcl_doors:register_trapdoor(name, def)
 
 	groups_open.trapdoor = 2
 	groups_open.not_in_creative_inventory = 1
+	-- Non-climbable opened
 	minetest.register_node(name.."_open", {
 		drawtype = "nodebox",
 		tiles = tiles_open,
@@ -200,9 +215,35 @@ function mcl_doors:register_trapdoor(name, def)
 		is_ground_content = false,
 		paramtype = "light",
 		paramtype2 = "facedir",
-		-- TODO: Implement Minecraft behaviour: Climbable if directly above
-		-- ladder w/ matching orientation.
-		-- Current behavour: Always climbable
+		sunlight_propagates = true,
+		pointable = true,
+		groups = groups_open,
+		_mcl_hardness = def._mcl_hardness,
+		_mcl_blast_resistance = def._mcl_blast_resistance,
+		sounds = def.sounds,
+		drop = name,
+		node_box = {
+			type = "fixed",
+			fixed = {-0.5, -0.5, 5/16, 0.5, 0.5, 0.5}
+		},
+		on_rightclick = on_rightclick,
+		mesecons = {effector = {
+			action_off = (function(pos, node)
+				punch(pos)
+			end),
+		}},
+		on_rotate = on_rotate,
+		_other = name .. "_ladder"
+	})
+
+	-- Climbable opened
+	minetest.register_node(name.."_ladder", {
+		drawtype = "nodebox",
+		tiles = tiles_open,
+		use_texture_alpha = minetest.features.use_texture_alpha_string_modes and "clip" or true,
+		is_ground_content = false,
+		paramtype = "light",
+		paramtype2 = "facedir",
 		climbable = true,
 		sunlight_propagates = true,
 		pointable = true,
@@ -222,6 +263,7 @@ function mcl_doors:register_trapdoor(name, def)
 			end),
 		}},
 		on_rotate = on_rotate,
+		_other = name .. "_open"
 	})
 
 	if minetest.get_modpath("doc") then