listener update

code/modules/modular_computers/file_system/programs/alarm.dm

@@ -9,7 +9,20 @@
 	tgui_id = "NtosStationAlertConsole"
 	program_icon = "bell"
 	var/has_alert = 0
-	var/alarms = list("Fire" = list(), "Atmosphere" = list(), "Power" = list())
+	///Listens for alarms, manages our listing of alarms
+	var/datum/alarm_listener/listener
+
+/datum/computer_file/program/alarm_monitor/New()
+	//We want to send an alarm if we're in one of the mining home areas
+	//Or if we're on station. Otherwise, die.
+	var/list/allowed_areas = GLOB.the_station_areas + typesof(/area/mine)
+	listener = new(list(ALARM_ATMOS, ALARM_FIRE, ALARM_POWER), null, allowed_areas)
+	RegisterSignal(listener, list(COMSIG_ALARM_TRIGGERED, COMSIG_ALARM_CLEARED), .proc/update_alarm_display)
+	return ..()
+
+/datum/computer_file/program/alarm_monitor/Destroy()
+	QDEL_NULL(listener)
+	return ..()
 
 /datum/computer_file/program/alarm_monitor/process_tick()
 	..()
@@ -29,87 +42,19 @@
 	var/list/data = get_header_data()
 
 	data["alarms"] = list()
-	for(var/class in alarms)
-		data["alarms"][class] = list()
-		for(var/area in alarms[class])
-			data["alarms"][class] += area
+	var/list/alarms = listener.alarms
+	for(var/alarm_type in alarms)
+		data["alarms"][alarm_type] = list()
+		for(var/area in alarms[alarm_type])
+			data["alarms"][alarm_type] += area
 
 	return data
 
-/datum/computer_file/program/alarm_monitor/proc/triggerAlarm(class, area/home, cameras, obj/source)
-	if(is_station_level(source.z))
-		if(!(home.type in GLOB.the_station_areas))
-			return
-	else if(!is_mining_level(source.z) || istype(home, /area/ruin))
-		return
-
-	var/list/our_sort = alarms[class]
-	for(var/areaname in our_sort)
-		if (areaname == home.name)
-			var/list/alarm = our_sort[areaname]
-			var/list/sources = alarm[3]
-			if (!(source in sources))
-				sources += source
-			return TRUE
-
-	var/obj/machinery/camera/cam = null
-	var/list/our_cams = null
-	if(cameras && islist(cameras))
-		our_cams = cameras
-		if (our_cams.len == 1)
-			cam = our_cams[1]
-	else if(cameras && istype(cameras, /obj/machinery/camera))
-		cam = cameras
-	our_sort[home.name] = list(home, (cam ? cam : cameras), list(source))
-
-	update_alarm_display()
-	return TRUE
-
-/datum/computer_file/program/alarm_monitor/proc/freeCamera(area/home, obj/machinery/camera/cam)
-	for(var/class in alarms)
-		var/our_area = alarms[class][home.name]
-		if(!our_area)
-			continue
-		var/cams = our_area[2] //Get the cameras
-		if(!cams)
-			continue
-		if(islist(cams))
-			cams -= cam
-			if(length(cams) == 1)
-				our_area[2] = cams[1]
-		else
-			our_area[2] = null
-
-/datum/computer_file/program/alarm_monitor/proc/cancelAlarm(class, area/A, obj/origin)
-	var/list/L = alarms[class]
-	var/cleared = 0
-	var/arealevelalarm = FALSE // set to TRUE for alarms that set/clear whole areas
-	if (class=="Fire")
-		arealevelalarm = TRUE
-	for (var/I in L)
-		if (I == A.name)
-			if (!arealevelalarm) // the traditional behaviour
-				var/list/alarm = L[I]
-				var/list/srcs  = alarm[3]
-				if (origin in srcs)
-					srcs -= origin
-				if (srcs.len == 0)
-					cleared = 1
-					L -= I
-			else
-				L -= I // wipe the instances entirely
-				cleared = 1
-
-
-	update_alarm_display()
-	return !cleared
-
 /datum/computer_file/program/alarm_monitor/proc/update_alarm_display()
+	SIGNAL_HANDLER
 	has_alert = FALSE
-	for(var/cat in alarms)
-		var/list/L = alarms[cat]
-		if(L.len)
-			has_alert = TRUE
+	if(length(listener.alarms))
+		has_alert = TRUE
 
 /datum/computer_file/program/alarm_monitor/run_program(mob/user)
 	. = ..(user)
@@ -117,4 +62,4 @@
 
 /datum/computer_file/program/alarm_monitor/kill_program(forced = FALSE)
 	GLOB.alarmdisplay -= src
-	..()
+	return ..()