added valid checking

cybersyn/scripts/central-planning.lua

@@ -42,11 +42,33 @@ function create_delivery(map_data, r_station_id, p_station_id, train_id, manifes
 	local train = map_data.trains[train_id]
 	local depot = map_data.depots[train.depot_id]
 
-	local is_at_depot = remove_available_train(map_data, train_id, train)
 
+	if not train.entity.valid then
+		on_train_broken(map_data, train_id, train)
+		interface_raise_train_dispatch_failed(train_id)
+		return
+	end
+	if not depot.entity_stop.valid then
+		on_depot_broken(map_data, train.depot_id, depot)
+		interface_raise_train_dispatch_failed(train_id)
+		return
+	end
+	if not p_station.entity_stop.valid then
+		on_station_broken(map_data, p_station_id, p_station)
+		interface_raise_train_dispatch_failed(train_id)
+		return
+	end
+	if not r_station.entity_stop.valid then
+		on_station_broken(map_data, r_station_id, r_station)
+		interface_raise_train_dispatch_failed(train_id)
+		return
+	end
+
+	local is_at_depot = remove_available_train(map_data, train_id, train)
 	--NOTE: we assume that the train is not being teleported at this time
-	--NOTE: set_manifest_schedule is allowed to cancel the delivery at the last second if applying the schedule to the train makes it lost
+	--NOTE: set_manifest_schedule is allowed to cancel the delivery at the last second if applying the schedule to the train makes it lost and is_at_depot == false
-	if set_manifest_schedule(map_data, train.entity, depot.entity_stop, not train.use_any_depot, p_station.entity_stop, p_station.enable_inactive, r_station.entity_stop, mod_settings.allow_cargo_in_depot and r_station.enable_inactive--[[@as boolean]], manifest, is_at_depot) then
+	local r_enable_inactive = mod_settings.allow_cargo_in_depot and r_station.enable_inactive--[[@as boolean]]
+	if set_manifest_schedule(map_data, train.entity, depot.entity_stop, not train.use_any_depot, p_station.entity_stop, p_station.enable_inactive, r_station.entity_stop, r_enable_inactive, manifest, is_at_depot) then
 		local old_status = train.status
 		train.status = STATUS_TO_P
 		train.p_station_id = p_station_id
@@ -255,7 +277,7 @@ local function tick_dispatch(map_data, mod_settings)
 		for i, id in ipairs(r_stations) do
 			local station = stations[id]
 			--NOTE: the station at r_station_id could have been deleted and reregistered since last poll, this check here prevents it from being processed for a delivery in that case
-			if not station or station.deliveries_total >= station.entity_stop.trains_limit then
+			if not station or station.deliveries_total >= station.trains_limit then
 				goto continue
 			end
 
@@ -331,7 +353,7 @@ local function tick_dispatch(map_data, mod_settings)
 
 			local p_station_id = p_stations[j]
 			local p_station = stations[p_station_id]
-			if not p_station or p_station.deliveries_total >= p_station.entity_stop.trains_limit then
+			if not p_station or p_station.deliveries_total >= p_station.trains_limit then
 				goto p_continue
 			end
 
@@ -403,7 +425,8 @@ local function tick_dispatch(map_data, mod_settings)
 					end
 
 					--check if path is shortest so we prioritize locality
-					local t_to_p_dist = get_stop_dist(train.entity.front_stock, p_station.entity_stop) - DEPOT_PRIORITY_MULT*train.priority
+					local t = get_any_train_entity(train.entity)
+					local t_to_p_dist = t and p_station.entity_stop.valid and (get_dist(t, p_station.entity_stop) - DEPOT_PRIORITY_MULT*train.priority) or INF
 					if capacity == best_capacity and t_to_p_dist > best_t_to_p_dist then
 						goto train_continue
 					end
@@ -443,7 +466,7 @@ local function tick_dispatch(map_data, mod_settings)
 				goto p_continue
 			end
 
-			best_p_dist = best_t_to_p_dist + get_stop_dist(p_station.entity_stop, r_station.entity_stop)
+			best_p_dist = p_station.entity_stop.valid and r_station.entity_stop.valid and (best_t_to_p_dist + get_dist(p_station.entity_stop, r_station.entity_stop)) or INF
 			if p_prior == best_p_prior and best_p_dist > best_dist then
 				goto p_continue
 			end
@@ -501,11 +524,7 @@ local function tick_poll_station(map_data, mod_settings)
 		station_id = map_data.active_station_ids[tick_data.i]
 		station = map_data.stations[station_id]
 		if station then
-			if station_id == 70487 then
+			if station.network_name then
-				local i = 0
-			end
-			--NOTE: polling trains_limit here is expensive and not strictly necessary but using it to early out saves more ups
-			if station.network_name and station.deliveries_total < station.entity_stop.trains_limit then
 				break
 			end
 		else
@@ -514,6 +533,12 @@ local function tick_poll_station(map_data, mod_settings)
 			tick_data.i = tick_data.i - 1
 		end
 	end
+	if station.entity_stop.valid and station.entity_comb1.valid and (not station.entity_comb2 or station.entity_comb2.valid) then
+		station.trains_limit = station.entity_stop.trains_limit
+	else
+		on_station_broken(map_data, station_id, station)
+		return false
+	end
 	station.r_threshold = mod_settings.r_threshold
 	station.priority = mod_settings.priority
 	station.item_priority = nil
@@ -673,13 +698,22 @@ function tick_poll_entities(map_data, mod_settings)
 		local refueler_id, _ = next(map_data.each_refuelers, tick_data.last_refueler)
 		tick_data.last_refueler = refueler_id
 		if refueler_id then
-			set_refueler_from_comb(map_data, mod_settings, refueler_id)
+			local refueler = map_data.refuelers[refueler_id]
+			if refueler.entity_stop.valid and refueler.entity_comb.valid then
+				set_refueler_from_comb(map_data, mod_settings, refueler_id, refueler)
+			else
+				on_refueler_broken(map_data, refueler_id, refueler)
+			end
 		end
 	else
 		local comb_id, comb = next(map_data.to_comb, tick_data.last_comb)
 		tick_data.last_comb = comb_id
-		if comb and comb.valid then
+		if comb then
+			if comb.valid then
 				combinator_update(map_data, comb, true)
+			else
+				map_data.to_comb[comb_id] = nil
+			end
 		end
 	end
 end
@@ -697,7 +731,11 @@ function tick_init(map_data, mod_settings)
 			if station.last_delivery_tick + mod_settings.warmup_time*mod_settings.tps < map_data.total_ticks then
 				map_data.active_station_ids[#map_data.active_station_ids + 1] = id
 				map_data.warmup_station_ids[i] = nil
+				if station.entity_comb1.valid then
 					combinator_update(map_data, station.entity_comb1)
+				else
+					on_station_broken(map_data, id, station)
+				end
 			end
 		else
 			map_data.warmup_station_ids[i] = nil
@@ -708,10 +746,14 @@ function tick_init(map_data, mod_settings)
 			local station = map_data.stations[id]
 			if station then
 				local pre = station.allows_all_trains
+				if station.entity_comb1.valid then
 					set_station_from_comb(station)
 					if station.allows_all_trains ~= pre then
 						update_stop_if_auto(map_data, station, true)
 					end
+				else
+					on_station_broken(map_data, id, station)
+				end
 			end
 		end
 		map_data.queue_station_update = nil

cybersyn/scripts/factorio-api.lua

@@ -15,10 +15,10 @@ function get_stack_size(map_data, item_name)
 	return game.item_prototypes[item_name].stack_size
 end
 
-
+---NOTE: does not check .valid
 ---@param entity0 LuaEntity
 ---@param entity1 LuaEntity
-function get_stop_dist(entity0, entity1)
+function get_dist(entity0, entity1)
 	local surface0 = entity0.surface.index
 	local surface1 = entity1.surface.index
 	return (surface0 == surface1 and get_distance(entity0.position, entity1.position) or DIFFERENT_SURFACE_DISTANCE)
@@ -41,7 +41,7 @@ end
 
 ---@param train LuaTrain
 function get_any_train_entity(train)
-	return train.front_stock or train.back_stock or train.carriages[1]
+	return train.valid and (train.front_stock or train.back_stock or train.carriages[1]) or nil
 end
 
 
@@ -109,15 +109,20 @@ end
 ---@param train LuaTrain
 ---@param depot_name string
 function set_depot_schedule(train, depot_name)
+	if train.valid then
 		train.schedule = {current = 1, records = {create_inactivity_order(depot_name)}}
 	end
+end
 
 ---@param train LuaTrain
 function lock_train(train)
+	if train.valid then
 		train.manual_mode = true
 	end
+end
 ---@param train LuaTrain
 function lock_train_to_depot(train)
+	if train.valid then
 		local schedule = train.schedule
 		if schedule then
 			local record = schedule.records[schedule.current]
@@ -136,11 +141,13 @@ function lock_train_to_depot(train)
 			train.manual_mode = true
 		end
 	end
+end
 
 ---@param train LuaTrain
 ---@param stop LuaEntity
 ---@param old_name string
 function rename_manifest_schedule(train, stop, old_name)
+	if train.valid then
 		local new_name = stop.backer_name
 		local schedule = train.schedule
 		if not schedule then return end
@@ -151,12 +158,14 @@ function rename_manifest_schedule(train, stop, old_name)
 		end
 		train.schedule = schedule
 	end
+end
 
 ---@param elevator_name string
 ---@param is_train_in_orbit boolean
 function se_create_elevator_order(elevator_name, is_train_in_orbit)
 	return {station = elevator_name..(is_train_in_orbit and SE_ELEVATOR_ORBIT_SUFFIX or SE_ELEVATOR_PLANET_SUFFIX)}
 end
+---NOTE: does not check .valid
 ---@param map_data MapData
 ---@param train LuaTrain
 ---@param depot_stop LuaEntity
@@ -281,6 +290,7 @@ function set_manifest_schedule(map_data, train, depot_stop, same_depot, p_stop,
 	return true
 end
 
+---NOTE: does not check .valid
 ---@param map_data MapData
 ---@param train LuaTrain
 ---@param stop LuaEntity
@@ -355,14 +365,8 @@ end
 function get_comb_params(comb)
 	return comb.get_or_create_control_behavior().parameters--[[@as ArithmeticCombinatorParameters]]
 end
----@param comb LuaEntity
-function get_comb_network_name(comb)
-	local params = get_comb_params(comb)
-	local signal = params.first_signal
-
-	return signal and signal.name or nil
-end
 
+---NOTE: does not check .valid
 ---@param station Station
 function set_station_from_comb(station)
 	--NOTE: this does nothing to update currently active deliveries
@@ -387,6 +391,7 @@ function set_station_from_comb(station)
 		station.network_flag = {}
 	end
 end
+---NOTE: does not check .valid
 ---@param mod_settings CybersynModSettings
 ---@param train Train
 ---@param comb LuaEntity
@@ -437,9 +442,9 @@ end
 ---@param map_data MapData
 ---@param mod_settings CybersynModSettings
 ---@param id uint
-function set_refueler_from_comb(map_data, mod_settings, id)
+---@param refueler Refueler
+function set_refueler_from_comb(map_data, mod_settings, id, refueler)
 	--NOTE: this does nothing to update currently active deliveries
-	local refueler = map_data.refuelers[id]
 	local params = get_comb_params(refueler.entity_comb)
 	local bits = params.second_constant or 0
 	local signal = params.first_signal
@@ -620,7 +625,6 @@ end
 
 ---@param station Station
 function get_signals(station)
-	--NOTE: the combinator must be valid, but checking for valid every time is too slow
 	local comb1 = station.entity_comb1
 	local status1 = comb1.status
 	---@type Signal[]?
@@ -693,7 +697,7 @@ end
 
 ---@param train LuaTrain
 function send_alert_sounds(train)
-	local loco = train.front_stock or train.back_stock
+	local loco = get_any_train_entity(train)
 	if loco then
 		for _, player in pairs(loco.force.players) do
 			player.play_sound({path = ALERT_SOUND})

cybersyn/scripts/global.lua

@@ -34,6 +34,7 @@
 ---@field public allows_all_trains true?
 ---@field public deliveries_total int
 ---@field public last_delivery_tick int
+---@field public trains_limit int --transient
 ---@field public priority int --transient
 ---@field public item_priority int? --transient
 ---@field public r_threshold int >= 0 --transient

cybersyn/scripts/layout.lua

@@ -596,14 +596,15 @@ function update_stop_from_rail(map_data, rail, forbidden_entity, force)
 			return
 		end
 		if entity.name == "train-stop" then
-			local id = entity.unit_number
+			local id = entity.unit_number--[[@as uint]]
 			local is_station = true
+			---@type Station|Refueler
 			local stop = map_data.stations[id]
 			if not stop then
 				stop = map_data.refuelers[id]
 				is_station = false
 			end
-			if stop then
+			if stop and stop.entity_stop.valid then
 				if force then
 					reset_stop_layout(map_data, stop, is_station, forbidden_entity)
 				elseif not stop.allows_all_trains then

cybersyn/scripts/main.lua

@@ -21,11 +21,12 @@ end
 ---@param map_data MapData
 ---@param depot_id uint
 ---@param depot Depot
-local function on_depot_broken(map_data, depot_id, depot)
+function on_depot_broken(map_data, depot_id, depot)
 	for train_id, train in pairs(map_data.trains) do
 		if train.depot_id == depot_id then
 			if train.use_any_depot then
 				local e = get_any_train_entity(train.entity)
+				if e then
 					local stops = e.force.get_train_stops({name = depot.entity_stop.backer_name, surface = e.surface})
 					for stop in rnext_consume, stops do
 						local new_depot_id = stop.unit_number
@@ -35,6 +36,7 @@ local function on_depot_broken(map_data, depot_id, depot)
 						end
 					end
 				end
+			end
 			lock_train(train.entity)
 			send_alert_depot_of_train_broken(map_data, train.entity)
 			remove_train(map_data, train_id, train)
@@ -63,14 +65,14 @@ local function on_refueler_built(map_data, stop, comb)
 	}
 	local id = stop.unit_number--[[@as uint]]
 	map_data.refuelers[id] = refueler
-	set_refueler_from_comb(map_data, mod_settings, id)
+	set_refueler_from_comb(map_data, mod_settings, id, refueler)
 	update_stop_if_auto(map_data, refueler, false)
 	interface_raise_refueler_created(id)
 end
 ---@param map_data MapData
 ---@param refueler_id uint
 ---@param refueler Refueler
-local function on_refueler_broken(map_data, refueler_id, refueler)
+function on_refueler_broken(map_data, refueler_id, refueler)
 	if refueler.trains_total > 0 then
 		--search for trains coming to the destroyed refueler
 		for train_id, train in pairs(map_data.trains) do
@@ -121,6 +123,7 @@ local function on_station_built(map_data, stop, comb1, comb2)
 		--allows_all_trains = set_station_from_comb,
 		deliveries_total = 0,
 		last_delivery_tick = map_data.total_ticks,
+		trains_limit = math.huge,
 		priority = 0,
 		item_priotity = nil,
 		r_threshold = 0,
@@ -150,7 +153,7 @@ end
 ---@param map_data MapData
 ---@param station_id uint
 ---@param station Station
-local function on_station_broken(map_data, station_id, station)
+function on_station_broken(map_data, station_id, station)
 	if station.deliveries_total > 0 then
 		--search for trains coming to the destroyed station
 		for train_id, train in pairs(map_data.trains) do
@@ -430,7 +433,7 @@ function combinator_update(map_data, comb, reset_display)
 				else
 					local refueler = map_data.refuelers[id]
 					if refueler and refueler.entity_comb == comb then
-						set_refueler_from_comb(map_data, mod_settings, id)
+						set_refueler_from_comb(map_data, mod_settings, id, refueler)
 					end
 				end
 			end
@@ -448,7 +451,7 @@ function combinator_update(map_data, comb, reset_display)
 			local refueler = map_data.refuelers[id]
 			if refueler then
 				local pre = refueler.allows_all_trains
-				set_refueler_from_comb(map_data, mod_settings, id)
+				set_refueler_from_comb(map_data, mod_settings, id, refueler)
 				if refueler.allows_all_trains ~= pre then
 					update_stop_if_auto(map_data, refueler, false)
 				end
@@ -757,19 +760,27 @@ local function setup_se_compat()
 		if schedule then
 			if train.status == STATUS_TO_P then
 				local stop = map_data.stations[train.p_station_id].entity_stop
+				if stop.valid then
 					se_add_direct_to_station_order(schedule, stop, old_surface_index)
 				end
+			end
 			if train.status == STATUS_TO_P or train.status == STATUS_TO_R then
 				local stop = map_data.stations[train.r_station_id].entity_stop
+				if stop.valid then
 					se_add_direct_to_station_order(schedule, stop, old_surface_index)
 				end
+			end
 			if train.status == STATUS_TO_F then
 				local stop = map_data.refuelers[train.refueler_id].entity_stop
+				if stop.valid then
 					se_add_direct_to_station_order(schedule, stop, old_surface_index)
 				end
+			end
 			if not train.use_any_depot then
-				local depot = map_data.depots[train.depot_id]
+				local stop = map_data.depots[train.depot_id].entity_stop
-				se_add_direct_to_station_order(schedule, depot.entity_stop, old_surface_index)
+				if stop.valid then
+					se_add_direct_to_station_order(schedule, stop, old_surface_index)
+				end
 			end
 			train_entity.schedule = schedule
 		end

cybersyn/scripts/train-events.lua

@@ -34,20 +34,24 @@ function on_failed_delivery(map_data, train_id, train)
 	local is_r_in_progress = is_p_in_progress or train.status == STATUS_TO_R or train.status == STATUS_R
 	if is_p_in_progress then
 		local station = map_data.stations[p_station_id]
+		if station.entity_comb1.valid and (not station.entity_comb2 or station.entity_comb2.valid) then
 			remove_manifest(map_data, station, manifest, 1)
 			if train.status == STATUS_P then
 				set_comb1(map_data, station, nil)
 				unset_wagon_combs(map_data, station)
 			end
 		end
+	end
 	if is_r_in_progress then
 		local station = map_data.stations[r_station_id]
+		if station.entity_comb1.valid and (not station.entity_comb2 or station.entity_comb2.valid) then
 			remove_manifest(map_data, station, manifest, -1)
 			if train.status == STATUS_R then
 				set_comb1(map_data, station, nil)
 				unset_wagon_combs(map_data, station)
 			end
 		end
+	end
 	if train.has_filtered_wagon then
 		train.has_filtered_wagon = nil
 		for carriage_i, carriage in ipairs(train.entity.cargo_wagons) do
@@ -100,7 +104,9 @@ end
 ---@param train Train
 function add_available_train_to_depot(map_data, mod_settings, train_id, train, depot_id, depot)
 	local comb = depot.entity_comb
+	if comb.valid then
 		set_train_from_comb(mod_settings, train, comb)
+	end
 	depot.available_train_id = train_id
 	train.depot_id = depot_id
 	train.status = STATUS_D
@@ -141,8 +147,9 @@ end
 
 ---@param map_data MapData
 ---@param depot_id uint
+---@param depot Depot
 ---@param train_entity LuaTrain
-local function on_train_arrives_depot(map_data, depot_id, train_entity)
+local function on_train_arrives_depot(map_data, depot_id, depot, train_entity)
 	local is_train_empty = next(train_entity.get_contents()) == nil and next(train_entity.get_fluid_contents()) == nil
 	local train_id = train_entity.id
 	local train = map_data.trains[train_id]
@@ -161,7 +168,6 @@ local function on_train_arrives_depot(map_data, depot_id, train_entity)
 		end
 		if is_train_empty or mod_settings.allow_cargo_in_depot then
 			local old_status = train.status
-			local depot = map_data.depots[depot_id]
 			add_available_train_to_depot(map_data, mod_settings, train_id, train, depot_id, depot)
 			set_depot_schedule(train_entity, depot.entity_stop.backer_name)
 			interface_raise_train_status_changed(train_id, old_status, STATUS_D)
@@ -194,7 +200,6 @@ local function on_train_arrives_depot(map_data, depot_id, train_entity)
 		}--[[@as Train]]
 		set_train_layout(map_data, train)
 		map_data.trains[train_id] = train
-		local depot = map_data.depots[depot_id]
 		add_available_train_to_depot(map_data, mod_settings, train_id, train, depot_id, depot)
 
 		set_depot_schedule(train_entity, depot.entity_stop.backer_name)
@@ -208,20 +213,18 @@ local function on_train_arrives_depot(map_data, depot_id, train_entity)
 	end
 end
 ---@param map_data MapData
----@param station_id uint
+---@param station Station
 ---@param train_id uint
 ---@param train Train
-local function on_train_arrives_station(map_data, station_id, train_id, train)
+local function on_train_arrives_station(map_data, station, train_id, train)
 	---@type uint
 	if train.status == STATUS_TO_P then
 		train.status = STATUS_P
-		local station = map_data.stations[station_id]
 		set_comb1(map_data, station, train.manifest, mod_settings.invert_sign and 1 or -1)
 		set_p_wagon_combs(map_data, station, train)
 		interface_raise_train_status_changed(train_id, STATUS_TO_P, STATUS_P)
 	elseif train.status == STATUS_TO_R then
 		train.status = STATUS_R
-		local station = map_data.stations[station_id]
 		set_comb1(map_data, station, train.manifest, mod_settings.invert_sign and -1 or 1)
 		set_r_wagon_combs(map_data, station, train)
 		interface_raise_train_status_changed(train_id, STATUS_TO_R, STATUS_R)
@@ -229,12 +232,11 @@ local function on_train_arrives_station(map_data, station_id, train_id, train)
 end
 
 ---@param map_data MapData
----@param refueler_id uint
+---@param refueler Refueler
 ---@param train_id uint
 ---@param train Train
-local function on_train_arrives_refueler(map_data, refueler_id, train_id, train)
+local function on_train_arrives_refueler(map_data, refueler, train_id, train)
 	if train.status == STATUS_TO_F then
-		local refueler = map_data.refuelers[refueler_id]
 		train.status = STATUS_F
 		set_refueler_combs(map_data, refueler, train)
 		interface_raise_train_status_changed(train_id, STATUS_TO_F, STATUS_F)
@@ -319,24 +321,26 @@ local function on_train_leaves_stop(map_data, mod_settings, train_id, train)
 					local best_prior = -INF
 					for id, _ in pairs(refuelers) do
 						local refueler = map_data.refuelers[id]
-						set_refueler_from_comb(map_data, mod_settings, id)
+						if not refueler.entity_stop.valid or not refueler.entity_comb.valid then
+							on_refueler_broken(map_data, id, refueler)
+						else
+							set_refueler_from_comb(map_data, mod_settings, id, refueler)
 
 							local refueler_network_flag = get_network_flag(refueler, network_name)
 							local train_network_flag = get_network_flag(train, network_name)
 							if btest(train_network_flag, refueler_network_flag) and (refueler.allows_all_trains or refueler.accepted_layouts[train.layout_id]) and refueler.trains_total < refueler.entity_stop.trains_limit then
-							local accepted = false
+								if refueler.priority >= best_prior then
-							local dist = nil
+									local t = get_any_train_entity(train.entity)
-							if refueler.priority == best_prior then
+									local dist = t and get_dist(t, refueler.entity_stop) or INF
-								dist = get_stop_dist(train.entity.front_stock, refueler.entity_stop)
+									if refueler.priority > best_prior or dist < best_dist then
-								accepted = dist < best_dist
-							end
-							if accepted or refueler.priority > best_prior then
 										best_refueler_id = id
-								best_dist = dist or get_stop_dist(train.entity.front_stock, refueler.entity_stop)
+										best_dist = dist
 										best_prior = refueler.priority
 									end
 								end
 							end
+						end
+					end
 					if best_refueler_id then
 						local refueler = map_data.refuelers[best_refueler_id]
 						if add_refueler_schedule(map_data, train.entity, refueler.entity_stop) then
@@ -358,7 +362,9 @@ local function on_train_leaves_stop(map_data, mod_settings, train_id, train)
 		train.refueler_id = nil
 		refueler.trains_total = refueler.trains_total - 1
 		unset_wagon_combs(map_data, refueler)
+		if refueler.entity_comb.valid then
 			set_combinator_output(map_data, refueler.entity_comb, nil)
+		end
 		if not train.disable_bypass then
 			train.status = STATUS_TO_D_BYPASS
 			add_available_train(map_data, train_id, train)
@@ -427,8 +433,13 @@ function on_train_changed(event)
 		local stop = train_e.station
 		if stop and stop.valid and stop.name == "train-stop" then
 			local id = stop.unit_number--[[@as uint]]
-			if map_data.depots[id] then
+			local depot = map_data.depots[id]
-				on_train_arrives_depot(map_data, id, train_e)
+			if depot then
+				if depot.entity_comb.valid and depot.entity_stop.valid then
+					on_train_arrives_depot(map_data, id, depot, train_e)
+				else
+					on_depot_broken(map_data, id, depot)
+				end
 			end
 		else
 			local train = map_data.trains[train_id]
@@ -451,11 +462,13 @@ function on_train_changed(event)
 							station = map_data.refuelers[id]
 							is_station = false
 						end
-						if id and station.entity_stop.connected_rail == rail then
+						if id and station.entity_stop.valid and station.entity_stop.connected_rail == rail then
 							if is_station then
-								on_train_arrives_station(map_data, id, train_id, train)
+								if station.entity_comb1 and (not station.entity_comb2 or station.entity_comb2.valid) then
-							else
+									on_train_arrives_station(map_data, station, train_id, train)
-								on_train_arrives_refueler(map_data, id, train_id, train)
+								end
+							elseif station.entity_comb.valid then
+								on_train_arrives_refueler(map_data, station, train_id, train)
 							end
 						end
 					end