Merge branch 'master' of https://github.com/orwell96/advtrains

1 files changed, 148 insertions, 0 deletions

diff --git a/advtrains/protection.lua b/advtrains/protection.lua
new file mode 100644
index 0000000..73b725f
--- /dev/null
+++ b/advtrains/protection.lua
@@ -0,0 +1,148 @@
+-- advtrains
+-- protection.lua: privileges and rail protection, and some helpers
+
+
+-- Privileges to control TRAIN DRIVING/COUPLING
+minetest.register_privilege("train_operator", {
+	description = "Without this privilege, a player can't do anything about trains, neither place or remove them nor drive or couple them (but he can build tracks if he has track_builder)",
+	give_to_singleplayer= true,
+});
+
+minetest.register_privilege("train_admin", {
+	description = "Player may drive, place or remove any trains from/to anywhere, regardless of owner, whitelist or protection",
+	give_to_singleplayer= true,
+});
+
+-- Privileges to control TRACK BUILDING
+minetest.register_privilege("track_builder", {
+	description = "Player can place and/or dig rails not protected from him. If he also has protection_bypass, he can place/dig any rails",
+	give_to_singleplayer= true,
+});
+
+-- Privileges to control OPERATING TURNOUTS/SIGNALS
+minetest.register_privilege("railway_operator", {
+	description = "Player can operate turnouts and signals not protected from him. If he also has protection_bypass, he can operate any turnouts/signals",
+	give_to_singleplayer= true,
+});
+
+-- there is a configuration option "allow_build_only_owner". If this is active, a player having track_builder can only build rails and operate signals/turnouts in an area explicitly belonging to him
+-- (checked using a dummy player called "*dummy*" (which is not an allowed player name))
+
+--[[
+Protection/privilege concept:
+Tracks:
+	Protected 1 node all around a rail and 4 nodes upward (maybe make this dynamically determined by the rail...)
+	if track_builder privilege:
+		if not protected from* player:
+			if allow_build_only_owner:
+				if unprotected:
+					deny
+			else:
+				allow
+	deny
+Wagons in general:
+	Players can only place/destroy wagons if they have train_operator
+Wagon driving controls:
+	The former seat_access tables are unnecessary, instead there is a whitelist for the driving stands
+	on player trying to access a driver stand:
+	if is owner or is on whitelist:
+		allow
+	else:
+		deny
+Wagon coupling:
+	Derived from the privileges for driving stands. The whitelist is shared (and also settable on non-driverstand wagons)
+	for each of the two bordering wagons:
+		if is owner or is on whitelist:
+			allow
+
+*"protected from" means the player is not allowed to do things, while "protected by" means that the player is (one of) the owner(s) of this area
+
+]]--
+
+local boo = minetest.settings:get_bool("advtrains_allow_build_to_owner")
+
+
+local nocheck
+-- Check if the node we are about to check is in the range of a track that is protected from a player
+--WARN: true means here that the action is forbidden!
+function advtrains.check_track_protection(pos, pname)
+	if nocheck or pname=="" then
+		return false
+	end
+	nocheck=true --prevent recursive calls, never check this again if we're already in
+	local r, vr = 1, 3
+	local nodes = minetest.find_nodes_in_area(
+		{x = pos.x - r, y = pos.y - vr, z = pos.z - r},
+		{x = pos.x + r, y = pos.y, z = pos.z + r},
+		{"group:advtrains_track"})
+	for _,npos in ipairs(nodes) do
+		if not minetest.check_player_privs(pname, {track_builder = true}) then
+			if boo and not minetest.is_protected(npos, pname) and minetest.is_protected(npos, "*dummy*") then
+				nocheck = false
+				return false
+			else
+				minetest.chat_send_player(pname, "You are not allowed to dig or place nodes near tracks (missing track_builder privilege)")
+				minetest.log("action", pname.." tried to dig/place nodes near the track at "..minetest.pos_to_string(npos).." but does not have track_builder")
+				nocheck = false
+				return true
+			end
+		end
+		if not minetest.check_player_privs(pname, {protection_bypass = true}) then
+			if minetest.is_protected(npos, pname) then
+				nocheck = false
+				minetest.record_protection_violation(pos, pname)
+				return true
+			end
+		end
+	end
+	nocheck=false
+	return false
+end
+
+local old_is_protected = minetest.is_protected
+minetest.is_protected = function(pos, pname)
+	if advtrains.check_track_protection(pos, pname) then
+		return true
+	end
+	return old_is_protected(pos, pname)
+end
+
+--WARN: true means here that the action is allowed!
+function advtrains.check_driving_couple_protection(pname, owner, whitelist)
+	if minetest.check_player_privs(pname, {train_admin = true}) then
+		return true
+	end
+	if not minetest.check_player_privs(pname, {train_operator = true}) then
+		return false
+	end
+	if not owner or owner == pname then
+		return true
+	end
+	if whitelist and string.find(" "..whitelist.." ", " "..pname.." ", nil, true) then
+		return true
+	end
+	return false
+end
+function advtrains.check_turnout_signal_protection(pos, pname)
+	nocheck=true
+	if not minetest.check_player_privs(pname, {railway_operator = true}) then
+		if boo and not minetest.is_protected(pos, pname) and minetest.is_protected(pos, "*dummy*") then
+			nocheck=false
+			return true
+		else
+			minetest.chat_send_player(pname, "You are not allowed to operate turnouts and signals (missing railway_operator privilege)")
+			minetest.log("action", pname.." tried to operate turnout/signal at "..minetest.pos_to_string(pos).." but does not have railway_operator")
+			nocheck=false
+			return false
+		end
+	end
+	if not minetest.check_player_privs(pname, {protection_bypass = true}) then
+		if minetest.is_protected(pos, pname) then
+			minetest.record_protection_violation(pos, pname)
+			nocheck=false
+			return false
+		end
+	end
+	nocheck=false
+	return true
+end