Ports Components from TG: "I don't actually know what I'm doing" edition (#8890)

God is with us.

code/controllers/subsystems/garbage.dm

@@ -187,9 +187,12 @@ var/datum/controller/subsystem/garbage_collector/SSgarbage
 	if(!istype(D))
 		del(D)
 	else if(isnull(D.gcDestroyed))
+		if (SEND_SIGNAL(D, COMSIG_PARENT_PREQDELETED, force)) // Give the components a chance to prevent their parent from being deleted
+			return
 		D.gcDestroyed = GC_CURRENTLY_BEING_QDELETED
 		var/start_time = world.time
 		var/hint = D.Destroy(force) // Let our friend know they're about to get fucked up.
+		SEND_SIGNAL(D, COMSIG_PARENT_QDELETING, force) // Let the (remaining) components know about the result of Destroy
 		if(world.time != start_time)
 			SSgarbage.sleptDestroy["[D.type]"]++
 		if(!D)

code/controllers/subsystems/processing/dcs.dm

@@ -0,0 +1,58 @@
+/var/datum/controller/subsystem/processing/dcs/SSdcs
+
+/datum/controller/subsystem/processing/dcs
+	name = "Datum Component System"
+	flags = SS_NO_INIT
+
+	var/list/elements_by_type = list()
+
+/datum/controller/subsystem/processing/dcs/New()
+	NEW_SS_GLOBAL(SSdcs)
+
+/datum/controller/subsystem/processing/dcs/Recover()
+	comp_lookup = SSdcs.comp_lookup
+
+/datum/controller/subsystem/processing/dcs/proc/GetElement(list/arguments)
+	var/datum/element/eletype = arguments[1]
+	var/element_id = eletype
+
+	if(!ispath(eletype, /datum/element))
+		CRASH("Attempted to instantiate [eletype] as a /datum/element")
+
+	if(initial(eletype.element_flags) & ELEMENT_BESPOKE)
+		element_id = GetIdFromArguments(arguments)
+
+	. = elements_by_type[element_id]
+	if(.)
+		return
+	. = elements_by_type[element_id] = new eletype
+
+/****
+	* Generates an id for bespoke elements when given the argument list
+	* Generating the id here is a bit complex because we need to support named arguments
+	* Named arguments can appear in any order and we need them to appear after ordered arguments
+	* We assume that no one will pass in a named argument with a value of null
+	**/
+/datum/controller/subsystem/processing/dcs/proc/GetIdFromArguments(list/arguments)
+	var/datum/element/eletype = arguments[1]
+	var/list/fullid = list("[eletype]")
+	var/list/named_arguments = list()
+	for(var/i in initial(eletype.id_arg_index) to length(arguments))
+		var/key = arguments[i]
+		var/value
+		if(istext(key))
+			value = arguments[key]
+		if(!(istext(key) || isnum(key)))
+			key = ref(key)
+		key = "[key]" // Key is stringified so numbers dont break things
+		if(!isnull(value))
+			if(!(istext(value) || isnum(value)))
+				value = ref(value)
+			named_arguments["[key]"] = value
+		else
+			fullid += "[key]"
+
+	if(length(named_arguments))
+		named_arguments = sortList(named_arguments)
+		fullid += named_arguments
+	return list2params(fullid)