Port Baystruments PR from tgstation

code/controllers/subsystem/processing/instruments.dm

@@ -0,0 +1,86 @@
+PROCESSING_SUBSYSTEM_DEF(instruments)
+	name = "Instruments"
+	init_order = INIT_ORDER_INSTRUMENTS
+	wait = 0.5
+	flags = SS_KEEP_TIMING
+	offline_implications = "Instruments will no longer play. No immediate action is needed."
+	stat_tag = "Instruments"
+
+	/// List of all instrument data, associative id = datum
+	var/list/datum/instrument/instrument_data
+	/// List of all song datums.
+	var/list/datum/song/songs
+	/// Max lines in songs
+	var/musician_maxlines = 600
+	/// Max characters per line in songs
+	var/musician_maxlinechars = 300
+	/// Deciseconds between hearchecks. Too high and instruments seem to lag when people are moving around in terms of who can hear it. Too low and the server lags from this.
+	var/musician_hearcheck_mindelay = 5
+	/// Maximum instrument channels total instruments are allowed to use. This is so you don't have instruments deadlocking all sound channels.
+	var/max_instrument_channels = MAX_INSTRUMENT_CHANNELS
+	/// Current number of channels allocated for instruments
+	var/current_instrument_channels = 0
+	/// Single cached list for synthesizer instrument ids, so you don't have to have a new list with every synthesizer.
+	var/list/synthesizer_instrument_ids
+
+/datum/controller/subsystem/processing/instruments/Initialize()
+	initialize_instrument_data()
+	synthesizer_instrument_ids = get_allowed_instrument_ids()
+	return ..()
+
+/**
+  * Initializes all instrument datums
+  */
+/datum/controller/subsystem/processing/instruments/proc/initialize_instrument_data()
+	instrument_data = list()
+	for(var/path in subtypesof(/datum/instrument))
+		var/datum/instrument/I = path
+		if(initial(I.abstract_type) == path)
+			continue
+		I = new path
+		I.Initialize()
+		if(!I.id)
+			qdel(I)
+			continue
+		instrument_data[I.id] = I
+		CHECK_TICK
+
+/**
+  * Reserves a sound channel for a given instrument datum
+  *
+  * Arguments:
+  * * I - The instrument datum
+  */
+/datum/controller/subsystem/processing/instruments/proc/reserve_instrument_channel(datum/instrument/I)
+	if(current_instrument_channels > max_instrument_channels)
+		return
+	. = SSsounds.reserve_sound_channel(I)
+	if(!isnull(.))
+		current_instrument_channels++
+
+/**
+  * Called when a datum/song is created
+  *
+  * Arguments:
+  * * S - The created datum/song
+  */
+/datum/controller/subsystem/processing/instruments/proc/on_song_new(datum/song/S)
+	LAZYADD(songs, S)
+
+/**
+  * Called when a datum/song is deleted
+  *
+  * Arguments:
+  * * S - The deleted datum/song
+  */
+/datum/controller/subsystem/processing/instruments/proc/on_song_del(datum/song/S)
+	LAZYREMOVE(songs, S)
+
+/**
+  * Returns the instrument datum at the given ID or path
+  *
+  * Arguments:
+  * * id_or_path - The ID or path of the instrument
+  */
+/datum/controller/subsystem/processing/instruments/proc/get_instrument(id_or_path)
+	return instrument_data["[id_or_path]"]