Forbid track modification when train, IP or TCB is on it, better handle removing of TCBs (H#149)

3 files changed, 68 insertions, 11 deletions

diff --git a/advtrains/locale/advtrains.de.tr b/advtrains/locale/advtrains.de.tr
index 520b200..f0d797f 100644
--- a/advtrains/locale/advtrains.de.tr
+++ b/advtrains/locale/advtrains.de.tr
@@ -64,3 +64,8 @@ Passenger Wagon=Passagierwaggon
 Box wagon=Güterwaggon
 Subway Passenger Wagon=U-Bahn-Waggon
 The wagon's inventory is not empty!=Das Inventar dieses Waggons ist nicht leer!
+This track can not be changed!=Diese Schiene kann nicht geändert werden!
+This track can not be rotated!=Diese Schiene kann nicht gedreht werden!
+Position is occupied by a train.=Ein Zug steht an dieser Position.
+There's a Track Circuit Break here.=Hier ist eine Gleisabschnittsgrenze (TCB).
+There's a Signal Influence Point here.=Hier ist ein Signal-Beeinflussungspunkt.
diff --git a/advtrains/trackplacer.lua b/advtrains/trackplacer.lua
index db65cd9..904d851 100644
--- a/advtrains/trackplacer.lua
+++ b/advtrains/trackplacer.lua
@@ -120,6 +120,11 @@ function tp.rail_and_can_be_bent(originpos, conn)
 			return advtrains.conn_matches_to(conn, cconns)
 		end
 	end
+	-- If the rail is not allowed to be modified, also only use if already in desired direction
+	if not advtrains.can_dig_or_modify_track(pos) then
+		local cconns=advtrains.get_track_connections(node.name, node.param2)
+		return advtrains.conn_matches_to(conn, cconns)
+	end
 	--rail at other end?
 	local adj1, adj2=tp.find_already_connected(pos)
 	if adj1 and adj2 then
@@ -326,15 +331,7 @@ minetest.register_craftitem("advtrains:trackworker",{
 				local node=minetest.get_node(pos)
 
 				--if not advtrains.is_track_and_drives_on(minetest.get_node(pos).name, advtrains.all_tracktypes) then return end
-				if advtrains.get_train_at_pos(pos) then return end
 				
-				if has_aux1_down then
-					--feature: flip the node by 180°
-					--i've always wanted this!
-					advtrains.ndb.swap_node(pos, {name=node.name, param2=(node.param2+2)%4})
-					return
-				end
-
 				local nnprefix, suffix, rotation=string.match(node.name, "^(.+)_([^_]+)(_[^_]+)$")
 				--atdebug(node.name.."\npattern recognizes:"..nnprefix.." / "..suffix.." / "..rotation)
 				--atdebug("nntab: ",tp.tracks[nnprefix])
@@ -346,6 +343,28 @@ minetest.register_craftitem("advtrains:trackworker",{
 						return
 					end
 				end
+				
+				-- check if the node is modify-protected
+				if advtrains.is_track_and_drives_on(minetest.get_node(pos).name, advtrains.all_tracktypes) then
+					-- is a track, we can query
+					local can_modify, reason = advtrains.can_dig_or_modify_track(pos)
+					if not can_modify then
+						local str = attrans("This track can not be rotated!")
+						if reason then
+							str = str .. " " .. reason
+						end
+						minetest.chat_send_player(placer:get_player_name(), str)
+						return
+					end
+				end
+				
+				if has_aux1_down then
+					--feature: flip the node by 180°
+					--i've always wanted this!
+					advtrains.ndb.swap_node(pos, {name=node.name, param2=(node.param2+2)%4})
+					return
+				end
+				
 				local modext=tp.tracks[nnprefix].twrotate[suffix]
 
 				if rotation==modext[#modext] then --increase param2
@@ -390,6 +409,21 @@ minetest.register_craftitem("advtrains:trackworker",{
 					return
 				  end
 				end
+				
+				-- check if the node is modify-protected
+				if advtrains.is_track_and_drives_on(minetest.get_node(pos).name, advtrains.all_tracktypes) then
+					-- is a track, we can query
+					local can_modify, reason = advtrains.can_dig_or_modify_track(pos)
+					if not can_modify then
+						local str = attrans("This track can not be changed!")
+						if reason then
+							str = str .. " " .. reason
+						end
+						minetest.chat_send_player(user:get_player_name(), str)
+						return
+					end
+				end
+				
 				local nextsuffix=tp.tracks[nnprefix].twcycle[suffix]
 				advtrains.ndb.swap_node(pos, {name=nnprefix.."_"..nextsuffix..rotation, param2=node.param2})
 				
diff --git a/advtrains/tracks.lua b/advtrains/tracks.lua
index 45d45ff..6799c40 100644
--- a/advtrains/tracks.lua
+++ b/advtrains/tracks.lua
@@ -478,9 +478,7 @@ function advtrains.register_tracks(tracktype, def, preset)
 						not_blocking_trains=1,

 					},

 						

-					can_dig=function(pos)

-						return not advtrains.get_train_at_pos(pos)

-					end,

+					can_dig = advtrains.can_dig_or_modify_track,

 					after_dig_node=function(pos)

 						advtrains.ndb.update(pos)

 					end,

@@ -602,6 +600,26 @@ function advtrains.get_track_connections(name, param2)
 	return advtrains.rotate_conn_by(nodedef.at_conns, noderot*AT_CMAX/4), (nodedef.at_rail_y or 0), tracktype

 end

 

+-- Function called when a track is about to be dug or modified by the trackworker

+-- Returns either true (ok) or false,"translated string describing reason why it isn't allowed"

+function advtrains.can_dig_or_modify_track(pos)

+	if advtrains.get_train_at_pos(pos) then

+		return false, attrans("Position is occupied by a train.")

+	end

+	-- interlocking: tcb, signal IP a.s.o.

+	if advtrains.interlocking then

+		-- TCB?

+		if advtrains.interlocking.db.get_tcb(pos) then

+			return false, attrans("There's a Track Circuit Break here.")

+		end

+		-- signal ip?

+		if advtrains.interlocking.db.is_ip_at(pos) then

+			return false, attrans("There's a Signal Influence Point here.")

+		end

+	end

+	return true

+end

+

 -- slope placer. Defined in register_tracks.

 --crafted with rail and gravel

 local sl={}