Basic main structure for centralized alarm handling.

code/modules/alarm/alarm.dm

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+/datum/alarm_source
+	var/source		= null	// The source trigger
+	var/source_name = ""	// The name of the source should it be lost (for example a destroyed camera)
+	var/duration	= 0		// How long this source will be alarming, 0 for indefinetely.
+	var/start_time	= 0		// When this source began alarming.
+	var/end_time	= 0		// Use to set when this trigger should clear, in case the source is lost.
+
+/datum/alarm_source/New(var/atom/source)
+	src.source = source
+	source_name = source.name
+	start_time = world.time
+
+/datum/alarm
+	var/atom/origin					//Used to identify the alarm area.
+	var/list/sources = new()		//List of sources triggering the alarm. Used to determine when the alarm should be cleared.
+	var/list/sources_assoc = new()	//Associative list of source triggers. Used to efficiently acquire the alarm source.
+	var/list/cameras				//List of cameras that can be switched to, if the player has that capability.
+	var/area/last_area				//The last acquired area, used should origin be lost (for example a destroyed borg containing an alarming camera).
+
+/datum/alarm/New(var/atom/origin, var/atom/source, var/duration)
+	src.origin = origin
+	last_area = alarm_area()
+	set_duration(source, duration)
+
+/datum/alarm/proc/set_duration(var/atom/source, var/duration)
+	var/datum/alarm_source/AS = sources[source]
+	if(!AS)
+		AS = new/datum/alarm_source(source)
+		sources += AS
+		sources_assoc[source] = AS
+	// Currently only non-0 durations can be altered (normal alarms VS EMP blasts)
+	if(AS.duration)
+		AS.duration = duration
+
+/datum/alarm/proc/clear(var/source)
+	var/datum/alarm_source/AS = sources[source]
+	sources -= AS
+	sources_assoc -= source
+
+/datum/alarm/proc/alarm_area()
+	if(!origin)
+		return last_area
+
+	last_area = origin.get_alarm_area()
+	return last_area
+
+/datum/alarm/proc/cameras()
+	if(!origin)
+		return list()
+
+	if(!cameras)
+		cameras = origin.get_alarm_cameras()
+
+	return cameras
+
+
+/atom/proc/get_alarm_area()
+	return get_area(src)
+
+/area/get_alarm_area()
+	return src
+
+/atom/proc/get_alarm_cameras()
+	var/area/A = get_area(src)
+	return A.get_cameras()
+
+/area/get_alarm_cameras()
+	return get_cameras()
+
+/mob/living/silicon/robot/get_alarm_cameras()
+	var/list/cameras = ..()
+	if(camera)
+		cameras += camera
+
+	return cameras
+
+/mob/living/silicon/robot/syndicate/get_alarm_cameras()
+	return list()