Fire: Ignite tnt, gunpowder, permanent flame above coalblock

Enable ignition of tnt, gunpowder and permanent
flame above coalblock using flint and steel
Override coalblock to remove flame above when dug
Add depends.txt for default mod

Author: paramat

mods/fire/depends.txt

@@ -0,0 +1 @@
+default

mods/fire/init.lua

@@ -80,26 +80,51 @@ minetest.register_node("fire:permanent_flame", {
 	end,
 })
 
+
+-- Flint and steel
+
 minetest.register_tool("fire:flint_and_steel", {
 	description = "Flint and Steel",
 	inventory_image = "fire_flint_steel.png",
 	on_use = function(itemstack, user, pointed_thing)
-		local player_name = user:get_player_name()
+		itemstack:add_wear(1000)
 		local pt = pointed_thing
-
-		if pt.type == "node" and minetest.get_node(pt.above).name == "air" then
-			itemstack:add_wear(1000)
+		if pt.type == "node" then
 			local node_under = minetest.get_node(pt.under).name
-
-			if minetest.get_item_group(node_under, "flammable") >= 1 then
-				if not minetest.is_protected(pt.above, player_name) then
-					minetest.set_node(pt.above, {name = "fire:basic_flame"})
-				else
-					minetest.chat_send_player(player_name, "This area is protected")
+			local is_coalblock = node_under == "default:coalblock"
+			local is_tnt = node_under == "tnt:tnt"
+			local is_gunpowder = node_under == "tnt:gunpowder"
+			if minetest.get_item_group(node_under, "flammable") >= 1 or
+					is_coalblock or is_tnt or is_gunpowder then
+				local flame_pos = pt.above
+				if is_coalblock then
+					flame_pos = {x = pt.under.x, y = pt.under.y + 1, z = pt.under.z}
+				elseif is_tnt or is_gunpowder then
+					flame_pos = pt.under
+				end
+				if minetest.get_node(flame_pos).name == "air" or
+						is_tnt or is_gunpowder then
+					local player_name = user:get_player_name()
+					if not minetest.is_protected(flame_pos, player_name) then
+						if is_coalblock then
+							minetest.set_node(flame_pos,
+								{name = "fire:permanent_flame"})
+						elseif is_tnt then
+							minetest.set_node(flame_pos,
+								{name = "tnt:tnt_burning"})
+						elseif is_gunpowder then
+							minetest.set_node(flame_pos,
+								{name = "tnt:gunpowder_burning"})
+						else
+							minetest.set_node(flame_pos,
+								{name = "fire:basic_flame"})
+						end
+					else
+						minetest.chat_send_player(player_name, "This area is protected")
+					end
 				end
 			end
 		end
-
 		if not minetest.setting_getbool("creative_mode") then
 			return itemstack
 		end
@@ -113,6 +138,20 @@ minetest.register_craft({
 	}
 })
 
+
+-- Override coalblock to enable permanent flame above
+-- Coalblock is non-flammable to avoid unwanted basic_flame nodes
+
+minetest.override_item("default:coalblock", {
+	after_destruct = function(pos, oldnode)
+		pos.y = pos.y + 1
+		if minetest.get_node(pos).name == "fire:permanent_flame" then
+			minetest.remove_node(pos)
+		end
+	end,
+})
+
+
 -- Get sound area of position
 
 fire.D = 6 -- size of sound areas