Ports Ambience Subsystem (#15613)

* Ports Ambience Subsystem

* re-include

code/controllers/subsystem/ambience.dm

@@ -0,0 +1,28 @@
+/// The subsystem used to play ambience to users every now and then, makes them real excited.
+SUBSYSTEM_DEF(ambience)
+	name = "Ambience"
+	flags = SS_BACKGROUND | SS_NO_INIT
+	priority = FIRE_PRIORITY_AMBIENCE
+	runlevels = RUNLEVEL_GAME | RUNLEVEL_POSTGAME
+	wait = 1 SECONDS
+	///Assoc list of listening client - next ambience time
+	var/list/ambience_listening_clients = list()
+
+/datum/controller/subsystem/ambience/fire(resumed)
+	for(var/C in ambience_listening_clients)
+		var/client/client_iterator = C
+
+		if(isnull(client_iterator))
+			ambience_listening_clients -= client_iterator
+			continue
+
+		if(ambience_listening_clients[client_iterator] > world.time)
+			continue //Not ready for the next sound
+
+		var/area/current_area = get_area(client_iterator.mob)
+
+		var/sound = pick(current_area.ambientsounds)
+
+		SEND_SOUND(client_iterator.mob, sound(sound, repeat = 0, wait = 0, volume = 25 * client_iterator.prefs.get_channel_volume(CHANNEL_AMBIENCE), channel = CHANNEL_AMBIENCE))
+
+		ambience_listening_clients[client_iterator] = world.time + rand(current_area.min_ambience_cooldown, current_area.max_ambience_cooldown)