perf: remove the periodic ghost receiver cleanup

changelog.txt

@@ -1,10 +1,12 @@
 ---------------------------------------------------------------------------------------------------
 Version: 1.2.0
-Date: 2020.12.12
+Date: 2020.12.20
   Features:
     - More mods compatibility. Battery Locomotive has come to handle `script_raised_built`, `script_raised_destroy` and `on_entity_cloned` events.
   Bugfixes:
     - Fixed a bug that caused a crash when an invalid BatteryLocomotive receiver entity was created for some reason.
+  Optimisations:
+    - Reduced the load by removing the internal processing that was being executed periodically.
   Modding:
     - Added remote interface to add a new battery locomotive type.
 ---------------------------------------------------------------------------------------------------

control.lua

@@ -53,6 +53,12 @@ local function remove_all_invalid_receivers()
     end
 end
 
+local function remove_uncontrolled_receiver(entity)
+    if not receiver.is_receiver(entity) then return end
+    if receiver.is_valid_receiver(global.entities, entity) then return end
+    entity.destroy()
+end
+
 script.on_event(defines.events.on_train_changed_state, function(event)
     if event.train.speed == 0 then
         --- create hidden receiver over locomotive when the train stopped
@@ -72,6 +78,7 @@ script.on_event({
 }, function(event)
     local entity = event.created_entity or event.entity or event.destination
     create_receiver(entity)
+    remove_uncontrolled_receiver(entity)
 end)
 
 script.on_event({
@@ -90,19 +97,6 @@ script.on_event({
     end
 end)
 
-script.on_nth_tick(180, function()
-    -- remove ghost receivers
-    remove_all_invalid_receivers()
-    for _, surface in pairs(game.surfaces) do
-        local receivers = surface.find_entities_filtered {name = key.receiver}
-        for _, r in pairs(receivers) do
-            if not receiver.is_valid_receiver(global.entities, r) then
-                r.destroy()
-            end
-        end
-    end
-end)
-
 -- receivers feed battery locomotives on every tick
 script.on_event(defines.events.on_tick, function()
     for i, e in pairs(global.entities) do

utils/receiver.lua

@@ -1,4 +1,10 @@
 local train = require "train"
+local key = require "key"
+
+local function is_receiver(entity)
+    if not entity then return false end
+    return entity.name == key.receiver
+end
 
 local function is_valid_receiver(global_pool, receiver)
     -- existence check
@@ -35,4 +41,8 @@ local function refuel(receiver, locomotive)
         locomotive.burner.remaining_burning_fuel + transfer_energy
 end
 
-return {is_valid_receiver = is_valid_receiver, refuel = refuel}
+return {
+    is_receiver = is_receiver,
+    is_valid_receiver = is_valid_receiver,
+    refuel = refuel
+}