Alarm centralization completion

Ensures the master area is always used, to avoid issues caused by dynamic lightning which splits areas into sub-areas.
Power alarms now handled centrally.

code/modules/alarm/alarm.dm

@@ -95,7 +95,7 @@
 
 /atom/proc/get_alarm_name()
 	var/area/A = get_area(src)
-	return A.name
+	return A.master.name
 
 /area/get_alarm_name()
 	return name

code/modules/alarm/alarm_handler.dm

@@ -15,8 +15,9 @@
 /datum/alarm_handler/proc/triggerAlarm(var/atom/origin, var/atom/source, var/duration = 0)
 	var/new_alarm
 	//Proper origin and source mandatory
-	if(!origin || !source)
+	if(!(origin && source))
 		return
+	origin = origin.get_alarm_origin()
 
 	new_alarm = 0
 	//see if there is already an alarm of this origin
@@ -37,8 +38,9 @@
 
 /datum/alarm_handler/proc/clearAlarm(var/atom/origin, var/source)
 	//Proper origin and source mandatory
-	if(!origin || !source)
+	if(!(origin && source))
 		return
+	origin = origin.get_alarm_origin()
 
 	var/datum/alarm/existing = alarms_assoc[origin]
 	if(existing)
@@ -53,6 +55,13 @@
 		return 1
 	return 0
 
+/atom/proc/get_alarm_origin()
+	return src
+
+/turf/get_alarm_origin()
+	var/area/area = get_area(src)
+	return area.master	// Very important to get area.master, as dynamic lightning can and will split areas.
+
 /datum/alarm_handler/proc/register(var/object, var/procName)
 	listeners[object] = procName
 

code/modules/alarm/power_alarm.dm

@@ -1,2 +1,10 @@
 /datum/alarm_handler/power
 	category = "Power"
+
+/datum/alarm_handler/power/notify_listeners(var/datum/alarm/alarm, var/was_raised)
+	..()
+	var/area/A = alarm.origin
+	if(istype(A))
+		A.power_alert(was_raised)
+
+/area/proc/power_alert(var/alarming)