Optimizes grid check event a bit (+minor fixes) (#96075)

code/modules/power/apc/apc_main.dm

@@ -100,7 +100,7 @@
 	var/long_term_power = 10
 	///Automatically name the APC after the area is in
 	var/auto_name = FALSE
-	///Time to allow the APC to regain some power and to turn the channels back online
+	///Time to allow the APC to regain some power and to turn the channels back online in seconds
 	var/failure_timer = 0
 	///Forces an update on the power use to ensure that the apc has enough power
 	var/force_update = FALSE
@@ -282,8 +282,8 @@
 
 /obj/machinery/power/apc/on_saboteur(datum/source, disrupt_duration)
 	. = ..()
-	disrupt_duration *= 0.1 // so, turns out, failure timer is in seconds, not deciseconds; without this, disruptions last 10 times as long as they probably should
-	energy_fail(disrupt_duration)
+	// failure timer is in seconds, not deciseconds, so we need to convert
+	energy_fail(disrupt_duration * 0.1)
 	return TRUE
 
 /obj/machinery/power/apc/on_set_is_operational(old_value)
@@ -589,7 +589,7 @@
 	if(!area?.requires_power)
 		return
 	if(failure_timer)
-		failure_timer--
+		failure_timer = max(0, failure_timer - seconds_per_tick)
 		force_update = TRUE
 		return
 

code/modules/power/apc/apc_power_proc.dm

@@ -127,16 +127,15 @@
 		terminal.master = null
 		terminal = null
 
+/**
+ * Temporarily disables all power to the room for a set duration
+ *
+ * Some rooms are immune to this effect due to having important machines
+ *
+ * * duration - the duration of the power failure in seconds (not deciseconds)
+ */
 /obj/machinery/power/apc/proc/energy_fail(duration)
-	for(var/obj/machinery/failing_machine in area.contents)
-		if(failing_machine.critical_machine)
-			return
-
-	for(var/mob/living/silicon/ai as anything in GLOB.ai_list)
-		if(get_area(ai) == area)
-			return
-
-	failure_timer = max(failure_timer, round(duration))
+	failure_timer = max(failure_timer, round(duration, SSMACHINES_DT))
 	update()
 	queue_icon_update()
 
@@ -147,10 +146,9 @@
 	if(nightshift_lights == on)
 		return //no change
 	nightshift_lights = on
-	for (var/list/zlevel_turfs as anything in area.get_zlevel_turf_lists())
-		for(var/turf/area_turf as anything in zlevel_turfs)
-			for(var/obj/machinery/light/night_light in area_turf)
-				if(night_light.nightshift_allowed)
-					night_light.nightshift_enabled = nightshift_lights
-					night_light.update(FALSE)
-				CHECK_TICK
+	for(var/turf/area_turf as anything in area.get_turfs_from_all_zlevels())
+		for(var/obj/machinery/light/night_light in area_turf)
+			if(night_light.nightshift_allowed)
+				night_light.nightshift_enabled = nightshift_lights
+				night_light.update(FALSE)
+			CHECK_TICK