Merge pull request #15892 from SandPoot/let's-sing-the-reference-clearing-song

Solves some harddels

code/__HELPERS/weakref.dm

@@ -0,0 +1,2 @@
+/// Checks if potential_weakref is a weakref of thing.
+#define IS_WEAKREF_OF(thing, potential_weakref) (istype(thing, /datum) && !isnull(potential_weakref) && thing.weak_reference == potential_weakref)

code/controllers/subsystem/throwing.dm

@@ -87,6 +87,7 @@ SUBSYSTEM_DEF(throwing)
 	if(HAS_TRAIT_FROM(thrownthing, TRAIT_SPOOKY_THROW, "revenant"))
 		REMOVE_TRAIT(thrownthing, TRAIT_SPOOKY_THROW, "revenant")
 	SSthrowing.processing -= thrownthing
+	SSthrowing.currentrun -= thrownthing
 	thrownthing.throwing = null
 	thrownthing = null
 	target = null

code/datums/action.dm

@@ -43,8 +43,7 @@
 	if(owner)
 		Remove(owner)
 	target = null
-	qdel(button)
-	button = null
+	QDEL_NULL(button)
 	return ..()
 
 /datum/action/proc/Grant(mob/M)

code/datums/wounds/_scars.dm

@@ -28,6 +28,8 @@
 		LAZYREMOVE(limb.scars, src)
 	if(victim)
 		LAZYREMOVE(victim.all_scars, src)
+	limb = null
+	victim = null
 	. = ..()
 
 /**
@@ -45,6 +47,8 @@
 		qdel(src)
 		return
 	limb = BP
+	RegisterSignal(limb, COMSIG_PARENT_QDELETING, .proc/limb_gone)
+
 	severity = W.severity
 	if(limb.owner)
 		victim = limb.owner
@@ -84,6 +88,7 @@
 		return
 
 	limb = BP
+	RegisterSignal(limb, COMSIG_PARENT_QDELETING, .proc/limb_gone)
 	src.severity = severity
 	LAZYADD(limb.scars, src)
 	if(BP.owner)
@@ -102,6 +107,10 @@
 			visibility = 7
 	return TRUE
 
+/datum/scar/proc/limb_gone()
+	SIGNAL_HANDLER
+	qdel(src)
+
 /// What will show up in examine_more() if this scar is visible
 /datum/scar/proc/get_examine_description(mob/viewer)
 	if(!victim || !is_visible(viewer))

code/datums/wounds/_wounds.dm

@@ -73,8 +73,6 @@
 
 	/// What status effect we assign on application
 	var/status_effect_type
-	/// The status effect we're linked to
-	var/datum/status_effect/linked_status_effect
 	/// If we're operating on this wound and it gets healed, we'll nix the surgery too
 	var/datum/surgery/attached_surgery
 	/// if you're a lazy git and just throw them in cryo, the wound will go away after accumulating severity * 25 power
@@ -127,12 +125,13 @@
 			return
 
 	victim = L.owner
+	RegisterSignal(victim, COMSIG_PARENT_QDELETING, .proc/null_victim)
 	limb = L
 	LAZYADD(victim.all_wounds, src)
 	LAZYADD(limb.wounds, src)
 	limb.update_wounds()
 	if(status_effect_type)
-		linked_status_effect = victim.apply_status_effect(status_effect_type, src)
+		victim.apply_status_effect(status_effect_type, src)
 	SEND_SIGNAL(victim, COMSIG_CARBON_GAIN_WOUND, src, limb)
 	victim.emote("pain")
 	if(!victim.alerts["wound"]) // only one alert is shared between all of the wounds
@@ -161,6 +160,14 @@
 		wound_injury(old_wound)
 		second_wind()
 
+/datum/wound/proc/null_victim()
+	SIGNAL_HANDLER
+	victim = null
+
+/datum/wound/proc/source_died()
+	SIGNAL_HANDLER
+	qdel(src)
+
 /// Remove the wound from whatever it's afflicting, and cleans up whateverstatus effects it had or modifiers it had on interaction times. ignore_limb is used for detachments where we only want to forget the victim
 /datum/wound/proc/remove_wound(ignore_limb, replaced = FALSE)
 	//TODO: have better way to tell if we're getting removed without replacement (full heal) scar stuff

code/game/area/areas.dm

@@ -15,7 +15,10 @@
 
 	var/area_flags = VALID_TERRITORY | BLOBS_ALLOWED | UNIQUE_AREA | CULT_PERMITTED
 
-	var/fire = null
+	///Do we have an active fire alarm?
+	var/fire = FALSE
+	///How many fire alarm sources do we have?
+	var/triggered_firealarms = 0
 	///Whether there is an atmos alarm in this area
 	var/atmosalm = FALSE
 	var/poweralm = FALSE
@@ -443,7 +446,18 @@ GLOBAL_LIST_EMPTY(teleportlocs)
 	START_PROCESSING(SSobj, src)
 
 /area/proc/firereset(obj/source)
-	if (fire)
+	var/should_reset_alarms = fire
+	if(source)
+		if(istype(source, /obj/machinery/firealarm))
+			var/obj/machinery/firealarm/alarm = source
+			if(alarm.triggered)
+				alarm.triggered = FALSE
+				triggered_firealarms -= 1
+		if(triggered_firealarms > 0)
+			should_reset_alarms = FALSE
+		should_reset_alarms = should_reset_alarms & power_environ //No resetting if there's no power
+
+	if (should_reset_alarms) // if there's a source, make sure there's no fire alarms left
 		set_fire_alarm_effects(FALSE)
 		ModifyFiredoors(TRUE)
 
@@ -463,6 +477,18 @@ GLOBAL_LIST_EMPTY(teleportlocs)
 
 	STOP_PROCESSING(SSobj, src)
 
+///Get rid of any dangling camera refs
+/area/proc/clear_camera(obj/machinery/camera/cam)
+	LAZYREMOVE(cameras, cam)
+	for (var/mob/living/silicon/aiPlayer as anything in GLOB.silicon_mobs)
+		aiPlayer.freeCamera(src, cam)
+	for (var/obj/machinery/computer/station_alert/comp as anything in GLOB.alert_consoles)
+		comp.freeCamera(src, cam)
+	for (var/mob/living/simple_animal/drone/drone_on as anything in GLOB.drones_list)
+		drone_on.freeCamera(src, cam)
+	for(var/datum/computer_file/program/alarm_monitor/monitor as anything in GLOB.alarmdisplay)
+		monitor.freeCamera(src, cam)
+
 /area/process()
 	if(firedoors_last_closed_on + 100 < world.time)	//every 10 seconds
 		ModifyFiredoors(FALSE)

code/game/atoms_movable.dm

@@ -117,11 +117,16 @@
 
 	. = ..()
 
+	//We add ourselves to this list, best to clear it out
+	// LAZYCLEARLIST(area_sensitive_contents)
+
 	for(var/movable_content in contents)
 		qdel(movable_content)
 
 	moveToNullspace()
 
+	vis_contents.Cut()
+
 /atom/movable/proc/update_emissive_block()
 	if(blocks_emissive != EMISSIVE_BLOCK_GENERIC)
 		return

code/game/machinery/Beacon.dm

@@ -38,7 +38,7 @@
 		icon_state = "[state]"
 
 /obj/machinery/bluespace_beacon/process()
-	if(!Beacon)
+	if(QDELETED(Beacon)) //Don't move it out of nullspace BACK INTO THE GAME for the love of god
 		var/turf/T = loc
 		Beacon = new(T)
 		Beacon.invisibility = INVISIBILITY_MAXIMUM

code/game/machinery/camera/camera.dm

@@ -81,15 +81,15 @@
 	if(can_use())
 		toggle_cam(null, 0) //kick anyone viewing out and remove from the camera chunks
 	GLOB.cameranet.cameras -= src
+	cancelCameraAlarm()
 	if(isarea(myarea))
-		LAZYREMOVE(myarea.cameras, src)
+		myarea.clear_camera(src)
 	QDEL_NULL(assembly)
 	if(bug)
-		bug.bugged_cameras -= src.c_tag
+		bug.bugged_cameras -= c_tag
 		if(bug.current == src)
 			bug.current = null
 		bug = null
-	cancelCameraAlarm()
 	return ..()
 
 /obj/machinery/camera/emp_act(severity)

code/game/machinery/computer/station_alert.dm

@@ -33,31 +33,46 @@
 
 	return data
 
-/obj/machinery/computer/station_alert/proc/triggerAlarm(class, area/A, O, obj/source)
+/obj/machinery/computer/station_alert/proc/triggerAlarm(class, area/home, cameras, obj/source)
 	if(source.z != z)
 		return
 	if(stat & (BROKEN))
 		return
 
-	var/list/L = alarms[class]
-	for(var/I in L)
-		if (I == A.name)
-			var/list/alarm = L[I]
+	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 1
-	var/obj/machinery/camera/C = null
-	var/list/CL = null
-	if(O && islist(O))
-		CL = O
-		if (CL.len == 1)
-			C = CL[1]
-	else if(O && istype(O, /obj/machinery/camera))
-		C = O
-	L[A.name] = list(A, (C ? C : O), list(source))
-	return 1
+			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))
+	return TRUE
+
+/obj/machinery/computer/station_alert/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
 
 /obj/machinery/computer/station_alert/proc/cancelAlarm(class, area/A, obj/origin)
 	if(stat & (BROKEN))

code/game/machinery/embedded_controller/embedded_controller_base.dm

@@ -3,6 +3,10 @@
 	var/state
 	var/obj/machinery/embedded_controller/master
 
+/datum/computer/file/embedded_program/Destroy()
+	master = null
+	. = ..()
+
 /datum/computer/file/embedded_program/proc/post_signal(datum/signal/signal, comm_line)
 	if(master)
 		master.post_signal(signal, comm_line)
@@ -25,6 +29,11 @@
 
 	var/on = TRUE
 
+/obj/machinery/embedded_controller/Destroy()
+	if(program)
+		QDEL_NULL(program)
+	. = ..()
+
 /obj/machinery/embedded_controller/ui_interact(mob/user)
 	. = ..()
 	user.set_machine(src)

code/game/machinery/firealarm.dm

@@ -33,8 +33,10 @@
 
 	var/detecting = 1
 	var/buildstage = 2 // 2 = complete, 1 = no wires, 0 = circuit gone
-	var/last_alarm = 0
+	COOLDOWN_DECLARE(last_alarm)
 	var/area/myarea = null
+	//Has this firealarm been triggered by its enviroment?
+	var/triggered = FALSE
 
 /obj/machinery/firealarm/Initialize(mapload, dir, building)
 	. = ..()
@@ -50,6 +52,7 @@
 	LAZYADD(myarea.firealarms, src)
 
 /obj/machinery/firealarm/Destroy()
+	myarea.firereset(src)
 	LAZYREMOVE(myarea.firealarms, src)
 	return ..()
 
@@ -102,7 +105,7 @@
 		. += mutable_appearance(icon, "fire_on")
 		. += emissive_appearance(icon, "fire_on")
 
-	if(!panel_open && detecting) //It just looks horrible with the panel open
+	if(!panel_open && detecting && triggered) //It just looks horrible with the panel open
 		. += "fire_detected"
 		. += mutable_appearance(icon, "fire_detected")
 		. += emissive_appearance(icon, "fire_detected") //Pain
@@ -129,14 +132,14 @@
 	return TRUE
 
 /obj/machinery/firealarm/temperature_expose(datum/gas_mixture/air, temperature, volume)
-	if((temperature > T0C + 200 || temperature < BODYTEMP_COLD_DAMAGE_LIMIT) && (last_alarm+FIREALARM_COOLDOWN < world.time) && !(obj_flags & EMAGGED) && detecting && !stat)
+	if((temperature > T0C + 200 || temperature < BODYTEMP_COLD_DAMAGE_LIMIT) && COOLDOWN_FINISHED(src, last_alarm) && !(obj_flags & EMAGGED) && detecting && !stat)
 		alarm()
-	..()
+	return ..()
 
 /obj/machinery/firealarm/proc/alarm(mob/user)
-	if(!is_operational() || (last_alarm+FIREALARM_COOLDOWN > world.time))
+	if(!is_operational() || !COOLDOWN_FINISHED(src, last_alarm))
 		return
-	last_alarm = world.time
+	COOLDOWN_START(src, last_alarm, FIREALARM_COOLDOWN)
 	var/area/A = get_base_area(src)
 	A.firealert(src)
 	playsound(loc, 'goon/sound/machinery/FireAlarm.ogg', 75)
@@ -147,7 +150,7 @@
 	if(!is_operational())
 		return
 	var/area/A = get_base_area(src)
-	A.firereset(src)
+	A.firereset()
 	if(user)
 		log_game("[user] reset a fire alarm at [COORD(src)]")
 

code/game/machinery/mechlaunchpad.dm

@@ -24,6 +24,7 @@
 		connected_console = null
 	for(var/obj/machinery/computer/mechpad/console in consoles)
 		console.mechpads -= src
+	GLOB.mechpad_list -= src
 	return ..()
 
 /obj/machinery/mechpad/screwdriver_act(mob/user, obj/item/tool)

code/game/objects/effects/decals/cleanable/gibs.dm

@@ -11,6 +11,7 @@
 	var/body_colors = "#e3ba84"	//a default color just in case.
 	var/gibs_reagent_id = /datum/reagent/liquidgibs
 	var/gibs_bloodtype = "A+"
+	turf_loc_check = FALSE
 
 /obj/effect/decal/cleanable/blood/gibs/Initialize(mapload, list/datum/disease/diseases, list/blood_data)
 	. = ..()
@@ -22,6 +23,9 @@
 		add_blood_DNA(list("Non-human DNA" = gibs_bloodtype), diseases)
 	update_icon()
 
+/obj/effect/decal/cleanable/blood/gibs/replace_decal(obj/effect/decal/cleanable/C)
+	return FALSE //Never fail to place us
+
 /obj/effect/decal/cleanable/blood/gibs/update_icon()
 	add_atom_colour(blood_DNA_to_color(), FIXED_COLOUR_PRIORITY)
 	cut_overlays()

code/game/objects/items/circuitboards/machine_circuitboards.dm

@@ -725,6 +725,26 @@
 	def_components = list(/obj/item/stock_parts/cell = /obj/item/stock_parts/cell/high)
 	needs_anchored = FALSE
 
+/obj/item/circuitboard/machine/chem_dispenser/fullupgrade
+	build_path = /obj/machinery/chem_dispenser/fullupgrade
+	req_components = list(
+		/obj/item/stock_parts/matter_bin/bluespace = 2,
+		/obj/item/stock_parts/capacitor/quadratic = 2,
+		/obj/item/stock_parts/manipulator/femto = 2,
+		/obj/item/stack/sheet/glass = 1,
+		/obj/item/stock_parts/cell/bluespace = 1,
+	)
+
+/obj/item/circuitboard/machine/chem_dispenser/mutagensaltpeter
+	build_path = /obj/machinery/chem_dispenser/mutagensaltpeter
+	req_components = list(
+		/obj/item/stock_parts/matter_bin/bluespace = 2,
+		/obj/item/stock_parts/capacitor/quadratic = 2,
+		/obj/item/stock_parts/manipulator/femto = 2,
+		/obj/item/stack/sheet/glass = 1,
+		/obj/item/stock_parts/cell/bluespace = 1,
+	)
+
 /obj/item/circuitboard/machine/chem_dispenser/apothecary
 	name = "Apotechary Chem Dispenser (Machine Board)"
 	build_path = /obj/machinery/chem_dispenser/apothecary
@@ -740,7 +760,13 @@
 	name = "Reagent Synthesizer (Abductor Machine Board)"
 	icon_state = "abductor_mod"
 	build_path = /obj/machinery/chem_dispenser/abductor
-	def_components = list(/obj/item/stock_parts/cell = /obj/item/stock_parts/cell/high)
+	req_components = list(
+		/obj/item/stock_parts/matter_bin/bluespace = 2,
+		/obj/item/stock_parts/capacitor/quadratic = 2,
+		/obj/item/stock_parts/manipulator/femto = 2,
+		/obj/item/stack/sheet/glass = 1,
+		/obj/item/stock_parts/cell/bluespace = 1,
+	)
 	needs_anchored = FALSE
 
 /obj/item/circuitboard/machine/chem_heater
@@ -1175,11 +1201,31 @@
 	icon_state = "service"
 	build_path = /obj/machinery/chem_dispenser/drinks
 
+/obj/item/circuitboard/machine/chem_dispenser/drinks/fullupgrade
+	build_path = /obj/machinery/chem_dispenser/drinks/fullupgrade
+	req_components = list(
+		/obj/item/stock_parts/matter_bin/bluespace = 2,
+		/obj/item/stock_parts/capacitor/quadratic = 2,
+		/obj/item/stock_parts/manipulator/femto = 2,
+		/obj/item/stack/sheet/glass = 1,
+		/obj/item/stock_parts/cell/bluespace = 1,
+	)
+
 /obj/item/circuitboard/machine/chem_dispenser/drinks/beer
 	name = "Booze Dispenser (Machine Board)"
 	icon_state = "service"
 	build_path = /obj/machinery/chem_dispenser/drinks/beer
 
+/obj/item/circuitboard/machine/chem_dispenser/drinks/beer/fullupgrade
+	build_path = /obj/machinery/chem_dispenser/drinks/beer/fullupgrade
+	req_components = list(
+		/obj/item/stock_parts/matter_bin/bluespace = 2,
+		/obj/item/stock_parts/capacitor/quadratic = 2,
+		/obj/item/stock_parts/manipulator/femto = 2,
+		/obj/item/stack/sheet/glass = 1,
+		/obj/item/stock_parts/cell/bluespace = 1,
+	)
+
 /obj/item/circuitboard/machine/chem_master/condi
 	name = "CondiMaster 3000 (Machine Board)"
 	icon_state = "service"

code/game/objects/items/devices/beacon.dm

@@ -17,7 +17,7 @@
 		icon_state = "beacon-off"
 
 /obj/item/beacon/Destroy()
-	GLOB.teleportbeacons.Remove(src)
+	GLOB.teleportbeacons -= src
 	return ..()
 
 /obj/item/beacon/attack_self(mob/user)
@@ -27,7 +27,7 @@
 		GLOB.teleportbeacons += src
 	else
 		icon_state = "beacon-off"
-		GLOB.teleportbeacons.Remove(src)
+		GLOB.teleportbeacons -= src
 	to_chat(user, "<span class='notice'>You [enabled ? "enable" : "disable"] the beacon.</span>")
 	return
 

code/game/objects/items/devices/taperecorder.dm

@@ -28,6 +28,10 @@
 		mytape = new starting_tape_type(src)
 	update_icon()
 
+/obj/item/taperecorder/Destroy()
+	// QDEL_NULL(soundloop)
+	QDEL_NULL(mytape)
+	return ..()
 
 /obj/item/taperecorder/examine(mob/user)
 	. = ..()

code/game/objects/items/tanks/jetpack.dm

@@ -19,6 +19,10 @@
 	ion_trail = new
 	ion_trail.set_up(src)
 
+/obj/item/tank/jetpack/Destroy()
+	QDEL_NULL(ion_trail)
+	return ..()
+
 /obj/item/tank/jetpack/populate_gas()
 	if(gas_type)
 		air_contents.set_moles(gas_type, ((6 * ONE_ATMOSPHERE) * volume / (R_IDEAL_GAS_EQUATION * T20C)))

code/game/objects/structures/crates_lockers/crates.dm

@@ -139,7 +139,7 @@
 
 /obj/structure/closet/crate/freezer/Destroy()
 	recursive_organ_check(src)
-	..()
+	return ..()
 
 /obj/structure/closet/crate/freezer/Initialize(mapload)
 	. = ..()

code/game/turfs/turf.dm

@@ -137,6 +137,8 @@ GLOBAL_LIST_EMPTY(station_turfs)
 	requires_activation = FALSE
 	..()
 
+	vis_contents.Cut()
+
 /turf/on_attack_hand(mob/user)
 	user.Move_Pulled(src)
 

code/modules/atmospherics/machinery/airalarm.dm

@@ -238,6 +238,8 @@
 	SSradio.remove_object(src, frequency)
 	qdel(wires)
 	wires = null
+	var/area/ourarea = get_area(src)
+	ourarea.atmosalert(FALSE, src)
 	return ..()
 
 /obj/machinery/airalarm/examine(mob/user)

code/modules/cargo/console.dm

@@ -40,7 +40,7 @@
 
 /obj/machinery/computer/cargo/Destroy()
 	QDEL_NULL(radio)
-	..()
+	return ..()
 
 /obj/machinery/computer/cargo/proc/get_export_categories()
 	. = EXPORT_CARGO

code/modules/clothing/gloves/tacklers.dm

@@ -25,6 +25,10 @@
 	/// See: [/datum/component/tackler/var/skill_mod]
 	var/skill_mod = 1
 
+/obj/item/clothing/gloves/tackler/Destroy()
+	tackler = null
+	return ..()
+
 /obj/item/clothing/gloves/tackler/equipped(mob/user, slot)
 	. = ..()
 	if(!ishuman(user))
@@ -34,12 +38,12 @@
 			var/mob/living/carbon/human/H = user
 			tackler = H.AddComponent(/datum/component/tackler, stamina_cost=tackle_stam_cost, base_knockdown = base_knockdown, range = tackle_range, speed = tackle_speed, skill_mod = skill_mod, min_distance = min_distance)
 		else
-			qdel(tackler) // Only wearing it!
+			QDEL_NULL(tackler) // Only wearing it!
 
 /obj/item/clothing/gloves/tackler/dropped(mob/user)
 	. = ..()
 	if(tackler)
-		qdel(tackler)
+		QDEL_NULL(tackler)
 
 /obj/item/clothing/gloves/tackler/dolphin
 	name = "dolphin gloves"

code/modules/lighting/lighting_source.dm

@@ -63,6 +63,10 @@
 	if (needs_update)
 		GLOB.lighting_update_lights -= src
 
+	top_atom = null
+	source_atom = null
+	source_turf = null
+	pixel_turf = null
 	. = ..()
 
 // Yes this doesn't align correctly on anything other than 4 width tabs.

code/modules/mob/living/carbon/alien/humanoid/alien_powers.dm

@@ -17,10 +17,6 @@ Doesn't work on other aliens/AI.*/
 	action_icon_state = "spell_default"
 	action_background_icon_state = "bg_alien"
 
-/obj/effect/proc_holder/alien/Initialize(mapload)
-	. = ..()
-	action = new(src)
-
 /obj/effect/proc_holder/alien/Trigger(mob/living/carbon/user, skip_cost_check = FALSE)
 	if(!istype(user))
 		return TRUE

code/modules/mob/living/silicon/ai/ai.dm

@@ -493,43 +493,61 @@
 	call_bot_cooldown = 0
 
 
-/mob/living/silicon/ai/triggerAlarm(class, area/A, O, obj/alarmsource)
-	if(alarmsource.z != z)
+/mob/living/silicon/ai/triggerAlarm(class, area/home, cameras, obj/source)
+	if(source.z != z)
 		return
-	var/list/L = alarms[class]
-	for (var/I in L)
-		if (I == A.name)
-			var/list/alarm = L[I]
+	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 (!(alarmsource in sources))
-				sources += alarmsource
-			return 1
-	var/obj/machinery/camera/C = null
-	var/list/CL = null
-	if (O && istype(O, /list))
-		CL = O
-		if (CL.len == 1)
-			C = CL[1]
-	else if (O && istype(O, /obj/machinery/camera))
-		C = O
-	L[A.name] = list(A, (C) ? C : O, list(alarmsource))
-	if (O)
-		if (C && C.can_use())
-			queueAlarm("--- [class] alarm detected in [A.name]! (<A HREF=?src=[REF(src)];switchcamera=[REF(C)]>[C.c_tag]</A>)", class)
-		else if (CL && CL.len)
+			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))
+
+	if (cameras)
+		if (cam?.can_use())
+			queueAlarm("--- [class] alarm detected in [home.name]! (<A HREF=?src=[REF(src)];switchcamera=[REF(cam)]>[cam.c_tag]</A>)", class)
+		else if (our_cams?.len)
 			var/foo = 0
 			var/dat2 = ""
-			for (var/obj/machinery/camera/I in CL)
+			for (var/obj/machinery/camera/I in our_cams)
 				dat2 += text("[]<A HREF=?src=[REF(src)];switchcamera=[REF(I)]>[]</A>", (!foo) ? "" : " | ", I.c_tag)	//I'm not fixing this shit...
 				foo = 1
-			queueAlarm(text ("--- [] alarm detected in []! ([])", class, A.name, dat2), class)
+			queueAlarm(text ("--- [] alarm detected in []! ([])", class, home.name, dat2), class)
 		else
-			queueAlarm(text("--- [] alarm detected in []! (No Camera)", class, A.name), class)
+			queueAlarm(text("--- [] alarm detected in []! (No Camera)", class, home.name), class)
 	else
-		queueAlarm(text("--- [] alarm detected in []! (No Camera)", class, A.name), class)
-	if (viewalerts) ai_alerts()
+		queueAlarm(text("--- [] alarm detected in []! (No Camera)", class, home.name), class)
+	if (viewalerts)
+		ai_alerts()
 	return 1
 
+/mob/living/silicon/ai/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
+
 /mob/living/silicon/ai/cancelAlarm(class, area/A, obj/origin)
 	var/list/L = alarms[class]
 	var/cleared = 0

code/modules/mob/living/silicon/robot/robot.dm

@@ -262,31 +262,47 @@
 /mob/living/silicon/robot/restrained(ignore_grab)
 	. = 0
 
-/mob/living/silicon/robot/triggerAlarm(class, area/A, O, obj/alarmsource)
-	if(alarmsource.z != z)
+/mob/living/silicon/robot/triggerAlarm(class, area/home, cameras, obj/source)
+	if(source.z != z)
 		return
 	if(stat == DEAD)
 		return 1
-	var/list/L = alarms[class]
-	for (var/I in L)
-		if (I == A.name)
-			var/list/alarm = L[I]
+	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 (!(alarmsource in sources))
-				sources += alarmsource
+			if (!(source in sources))
+				sources += source
 			return 1
-	var/obj/machinery/camera/C = null
-	var/list/CL = null
-	if (O && istype(O, /list))
-		CL = O
-		if (CL.len == 1)
-			C = CL[1]
-	else if (O && istype(O, /obj/machinery/camera))
-		C = O
-	L[A.name] = list(A, (C) ? C : O, list(alarmsource))
-	queueAlarm(text("--- [class] alarm detected in [A.name]!"), class)
+
+	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))
+	queueAlarm(text("--- [class] alarm detected in [home.name]!"), class)
 	return TRUE
 
+/mob/living/silicon/robot/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
+
 /mob/living/silicon/robot/cancelAlarm(class, area/A, obj/origin)
 	var/list/L = alarms[class]
 	var/cleared = 0

code/modules/mob/living/silicon/silicon.dm

@@ -87,6 +87,9 @@
 /mob/living/silicon/proc/cancelAlarm()
 	return
 
+/mob/living/silicon/proc/freeCamera()
+	return
+
 /mob/living/silicon/proc/triggerAlarm()
 	return
 

code/modules/mob/living/simple_animal/bot/bot.dm

@@ -194,9 +194,9 @@
 	GLOB.bots_list -= src
 	if(paicard)
 		ejectpai()
-	qdel(Radio)
-	qdel(access_card)
-	qdel(bot_core)
+	QDEL_NULL(Radio)
+	QDEL_NULL(access_card)
+	QDEL_NULL(bot_core)
 	return ..()
 
 /mob/living/simple_animal/bot/bee_friendly()

code/modules/mob/living/simple_animal/friendly/drone/_drone.dm

@@ -231,20 +231,26 @@
 		adjustBruteLoss(heavy_emp_damage)
 		to_chat(src, "<span class='userdanger'>HeAV% DA%^MMA+G TO I/O CIR!%UUT!</span>")
 
-/mob/living/simple_animal/drone/proc/triggerAlarm(class, area/A, O, obj/alarmsource)
-	if(alarmsource.z != z)
+/mob/living/simple_animal/drone/proc/triggerAlarm(class, area/home, cameras, obj/source)
+	if(source.z != z)
 		return
-	if(stat != DEAD)
-		var/list/L = src.alarms[class]
-		for (var/I in L)
-			if (I == A.name)
-				var/list/alarm = L[I]
-				var/list/sources = alarm[2]
-				if (!(alarmsource in sources))
-					sources += alarmsource
-				return
-		L[A.name] = list(A, list(alarmsource))
-		to_chat(src, "--- [class] alarm detected in [A.name]!")
+	if(stat == DEAD)
+		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
+
+	our_sort[home.name] = list(home, list(source))
+	to_chat(src, "--- [class] alarm detected in [home.name]!")
+
+///This isn't currently needed since drones do jack shit with cameras. I hate this code so much
+/mob/living/simple_animal/drone/proc/freeCamera(area/home, obj/machinery/camera/cam)
+	return
 
 /mob/living/simple_animal/drone/proc/cancelAlarm(class, area/A, obj/origin)
 	if(stat != DEAD)

code/modules/mob/mob_lists.dm

@@ -10,6 +10,8 @@
 
 ///Adds the mob reference to the list of all mobs alive. If mob is cliented, it adds it to the list of all living player-mobs.
 /mob/proc/add_to_alive_mob_list()
+	if(QDELETED(src))
+		return
 	GLOB.alive_mob_list |= src
 	if(client)
 		add_to_current_living_players()
@@ -23,6 +25,8 @@
 
 ///Adds the mob reference to the list of all the dead mobs. If mob is cliented, it adds it to the list of all dead player-mobs.
 /mob/proc/add_to_dead_mob_list()
+	if(QDELETED(src))
+		return
 	GLOB.dead_mob_list |= src
 	if(client)
 		add_to_current_dead_players()

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

@@ -36,35 +36,49 @@
 
 	return data
 
-/datum/computer_file/program/alarm_monitor/proc/triggerAlarm(class, area/A, O, obj/source)
+/datum/computer_file/program/alarm_monitor/proc/triggerAlarm(class, area/home, cameras, obj/source)
 	if(is_station_level(source.z))
-		if(!(A.type in GLOB.the_station_areas))
+		if(!(home.type in GLOB.the_station_areas))
 			return
-	else if(!is_mining_level(source.z) || istype(A, /area/ruin))
+	else if(!is_mining_level(source.z) || istype(home, /area/ruin))
 		return
 
-	var/list/L = alarms[class]
-	for(var/I in L)
-		if (I == A.name)
-			var/list/alarm = L[I]
+	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 1
-	var/obj/machinery/camera/C = null
-	var/list/CL = null
-	if(O && istype(O, /list))
-		CL = O
-		if (CL.len == 1)
-			C = CL[1]
-	else if(O && istype(O, /obj/machinery/camera))
-		C = O
-	L[A.name] = list(A, (C ? C : O), list(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
 
-	return 1
-
+/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]

code/modules/paperwork/ticketmachine.dm

@@ -82,15 +82,15 @@
 		if(M.buffer && !istype(M.buffer, /obj/machinery/ticket_machine))
 			return
 		var/obj/item/assembly/control/ticket_machine/controller = device
-		controller.linked = M.buffer
+		controller.linked = WEAKREF(M.buffer)
 		id = null
 		controller.id = null
-		to_chat(user, "<span class='warning'>You've linked [src] to [controller.linked].</span>")
+		to_chat(user, "<span class='warning'>You've linked [src] to [M.buffer].</span>")
 
 /obj/item/assembly/control/ticket_machine
 	name = "ticket machine controller"
 	desc = "A remote controller for the HoP's ticket machine."
-	var/obj/machinery/ticket_machine/linked //To whom are we linked?
+	var/datum/weakref/linked //To whom are we linked?
 
 /obj/item/assembly/control/ticket_machine/Initialize(mapload)
 	..()
@@ -102,7 +102,7 @@
 /obj/item/assembly/control/ticket_machine/proc/find_machine() //Locate the one to which we're linked
 	for(var/obj/machinery/ticket_machine/ticketsplease in GLOB.machines)
 		if(ticketsplease.id == id)
-			linked = ticketsplease
+			linked = WEAKREF(ticketsplease)
 	if(linked)
 		return TRUE
 	else
@@ -113,8 +113,11 @@
 		return
 	if(!linked)
 		return
+	var/obj/machinery/ticket_machine/machine = linked.resolve()
+	if(!machine)
+		return
 	cooldown = TRUE
-	linked.increment()
+	machine.increment()
 	addtimer(VARSET_CALLBACK(src, cooldown, FALSE), 10)
 
 /obj/machinery/ticket_machine/update_icon()

code/modules/power/apc.dm

@@ -300,7 +300,7 @@
 	area.power_equip = FALSE
 	area.power_environ = FALSE
 	area.power_change()
-	area.poweralert(TRUE, src)
+	area.poweralert(FALSE, src)
 	if(occupier)
 		malfvacate(1)
 	qdel(wires)

code/modules/power/lighting.dm

@@ -500,7 +500,7 @@
 				drop_light_tube()
 			new /obj/item/stack/cable_coil(loc, 1, "red")
 		transfer_fingerprints_to(newlight)
-		if(cell)
+		if(!QDELETED(cell))
 			newlight.cell = cell
 			cell.forceMove(newlight)
 			cell = null

code/modules/reagents/chemistry/machinery/chem_dispenser.dm

@@ -628,19 +628,11 @@
 	desc = "Contains a large reservoir of soft drinks. This model has had its safeties shorted out."
 	obj_flags = CAN_BE_HIT | EMAGGED
 	flags_1 = NODECONSTRUCT_1
+	circuit = /obj/item/circuitboard/machine/chem_dispenser/drinks/fullupgrade
 
 /obj/machinery/chem_dispenser/drinks/fullupgrade/Initialize(mapload)
 	. = ..()
 	dispensable_reagents |= emagged_reagents //adds emagged reagents
-	component_parts = list()
-	component_parts += new /obj/item/circuitboard/machine/chem_dispenser/drinks(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/capacitor/quadratic(null)
-	component_parts += new /obj/item/stock_parts/manipulator/femto(null)
-	component_parts += new /obj/item/stack/sheet/glass(null)
-	component_parts += new /obj/item/stock_parts/cell/bluespace(null)
-	RefreshParts()
 
 /obj/machinery/chem_dispenser/drinks/beer
 	name = "booze dispenser"
@@ -688,19 +680,11 @@
 	desc = "Contains a large reservoir of the good stuff. This model has had its safeties shorted out."
 	obj_flags = CAN_BE_HIT | EMAGGED
 	flags_1 = NODECONSTRUCT_1
+	circuit = /obj/item/circuitboard/machine/chem_dispenser/drinks/beer/fullupgrade
 
 /obj/machinery/chem_dispenser/drinks/beer/fullupgrade/Initialize(mapload)
 	. = ..()
 	dispensable_reagents |= emagged_reagents //adds emagged reagents
-	component_parts = list()
-	component_parts += new /obj/item/circuitboard/machine/chem_dispenser/drinks/beer(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/capacitor/quadratic(null)
-	component_parts += new /obj/item/stock_parts/manipulator/femto(null)
-	component_parts += new /obj/item/stack/sheet/glass(null)
-	component_parts += new /obj/item/stock_parts/cell/bluespace(null)
-	RefreshParts()
 
 /obj/machinery/chem_dispenser/mutagen
 	name = "mutagen dispenser"
@@ -716,6 +700,7 @@
 	desc = "Creates and dispenses chemicals useful for botany."
 	flags_1 = NODECONSTRUCT_1
 	canStore = FALSE
+	circuit = /obj/item/circuitboard/machine/chem_dispenser/mutagensaltpeter
 
 	dispensable_reagents = list(
 		/datum/reagent/toxin/mutagen,
@@ -736,35 +721,15 @@
 	upgrade_reagents2 = null
 	upgrade_reagents3 = null
 
-/obj/machinery/chem_dispenser/mutagensaltpeter/Initialize(mapload)
-	. = ..()
-	component_parts = list()
-	component_parts += new /obj/item/circuitboard/machine/chem_dispenser(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/capacitor/quadratic(null)
-	component_parts += new /obj/item/stock_parts/manipulator/femto(null)
-	component_parts += new /obj/item/stack/sheet/glass(null)
-	component_parts += new /obj/item/stock_parts/cell/bluespace(null)
-	RefreshParts()
-
 /obj/machinery/chem_dispenser/fullupgrade //fully ugpraded stock parts, emagged
 	desc = "Creates and dispenses chemicals. This model has had its safeties shorted out."
 	obj_flags = CAN_BE_HIT | EMAGGED
 	flags_1 = NODECONSTRUCT_1
+	circuit = /obj/item/circuitboard/machine/chem_dispenser/fullupgrade
 
 /obj/machinery/chem_dispenser/fullupgrade/Initialize(mapload)
 	. = ..()
 	dispensable_reagents |= emagged_reagents //adds emagged reagents
-	component_parts = list()
-	component_parts += new /obj/item/circuitboard/machine/chem_dispenser(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/capacitor/quadratic(null)
-	component_parts += new /obj/item/stock_parts/manipulator/femto(null)
-	component_parts += new /obj/item/stack/sheet/glass(null)
-	component_parts += new /obj/item/stock_parts/cell/bluespace(null)
-	RefreshParts()
 
 /obj/machinery/chem_dispenser/abductor
 	name = "reagent synthesizer"
@@ -818,18 +783,6 @@
 		/datum/reagent/medicine/morphine
 	)
 
-/obj/machinery/chem_dispenser/abductor/Initialize(mapload)
-	. = ..()
-	component_parts = list()
-	component_parts += new /obj/item/circuitboard/machine/chem_dispenser(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(null)
-	component_parts += new /obj/item/stock_parts/capacitor/quadratic(null)
-	component_parts += new /obj/item/stock_parts/manipulator/femto(null)
-	component_parts += new /obj/item/stack/sheet/glass(null)
-	component_parts += new /obj/item/stock_parts/cell/bluespace(null)
-	RefreshParts()
-
 ///An unique, less efficient model found in the medbay apothecary room.
 /obj/machinery/chem_dispenser/apothecary
 	name = "apothecary chem dispenser"

code/modules/recycling/disposal/pipe.dm

@@ -54,7 +54,7 @@
 	if(H)
 		H.active = FALSE
 		expel(H, get_turf(src), 0)
-	QDEL_NULL(stored)
+	stored = null //The qdel is handled in expel()
 	return ..()
 
 // returns the direction of the next pipe object, given the entrance dir

code/modules/spells/spell.dm

@@ -35,6 +35,7 @@
 GLOBAL_LIST_INIT(spells, typesof(/obj/effect/proc_holder/spell)) //needed for the badmin verb for now
 
 /obj/effect/proc_holder/Destroy()
+	QDEL_NULL(action)
 	if(ranged_ability_user)
 		remove_ranged_ability()
 	return ..()

code/modules/surgery/bodyparts/_bodyparts.dm

@@ -9,7 +9,7 @@
 	icon_state = ""
 	layer = BELOW_MOB_LAYER //so it isn't hidden behind objects when on the floor
 	var/mob/living/carbon/owner = null
-	var/mob/living/carbon/original_owner = null
+	var/datum/weakref/original_owner = null
 	var/status = BODYPART_ORGANIC
 	var/needs_processing = FALSE
 
@@ -639,8 +639,8 @@
 	if(source)
 		C = source
 		if(!original_owner)
-			original_owner = source
-	else if(original_owner && owner != original_owner) //Foreign limb
+			original_owner = WEAKREF(source)
+	else if(original_owner && !IS_WEAKREF_OF(owner, original_owner)) //Foreign limb
 		no_update = TRUE
 	else
 		C = owner

code/modules/vehicles/mecha/_mecha.dm

@@ -167,6 +167,7 @@
 	hud_possible = list (DIAG_STAT_HUD, DIAG_BATT_HUD, DIAG_MECH_HUD, DIAG_TRACK_HUD)
 
 /obj/item/radio/mech //this has to go somewhere
+	subspace_transmission = TRUE
 
 /obj/vehicle/sealed/mecha/Initialize(mapload)
 	. = ..()
@@ -196,41 +197,40 @@
 	update_icon()
 
 /obj/vehicle/sealed/mecha/Destroy()
-	if(obj_integrity > 0) //no explody if we have hp remaining!
-		explode_on_death = FALSE
-	for(var/M in occupants)
-		var/mob/living/occupant = M
-		if(isAI(occupant))
-			occupant.gib() //No wreck, no AI to recover
-		else
-			occupant.forceMove(loc)
-			occupant.SetSleeping(destruction_sleep_duration)
+	for(var/ejectee in occupants)
+		mob_exit(ejectee, TRUE, TRUE)
 	if(LAZYLEN(equipment))
-		for(var/E in equipment)
-			var/obj/item/mecha_parts/mecha_equipment/equip = E
+		for(var/obj/item/mecha_parts/mecha_equipment/equip as anything in equipment)
 			equip.detach(loc)
 			qdel(equip)
-	if(cell)
-		QDEL_NULL(cell)
-	if(scanmod)
-		QDEL_NULL(scanmod)
-	if(capacitor)
-		QDEL_NULL(capacitor)
-	if(internal_tank)
-		QDEL_NULL(internal_tank)
+	radio = null
+
 	STOP_PROCESSING(SSobj, src)
-	GLOB.poi_list.Remove(src)
 	LAZYCLEARLIST(equipment)
-	if(loc)
-		loc.assume_air(cabin_air)
-		air_update_turf()
-	else
-		qdel(cabin_air)
-	cabin_air = null
+
+	QDEL_NULL(cell)
+	QDEL_NULL(scanmod)
+	QDEL_NULL(capacitor)
+	QDEL_NULL(internal_tank)
+	QDEL_NULL(cabin_air)
 	QDEL_NULL(spark_system)
 	QDEL_NULL(smoke_system)
 
+	GLOB.poi_list -= src
 	GLOB.mechas_list -= src //global mech list
+	for(var/datum/atom_hud/data/diagnostic/diag_hud in GLOB.huds)
+		diag_hud.remove_from_hud(src) //YEET
+	return ..()
+
+/obj/vehicle/sealed/mecha/obj_destruction()
+	loc.assume_air(cabin_air)
+	air_update_turf(FALSE, FALSE)
+	for(var/mob/living/occupant as anything in occupants)
+		if(isAI(occupant))
+			occupant.gib() //No wreck, no AI to recover
+			continue
+		mob_exit(occupant, FALSE, TRUE)
+		occupant.SetSleeping(destruction_sleep_duration)
 	return ..()
 
 /obj/vehicle/sealed/mecha/update_icon()

tgstation.dme

@@ -222,6 +222,7 @@
 #include "code\__HELPERS\vector.dm"
 #include "code\__HELPERS\verbs.dm"
 #include "code\__HELPERS\view.dm"
+#include "code\__HELPERS\weakref.dm"
 #include "code\__HELPERS\yelling.dm"
 #include "code\__HELPERS\matrices\color_matrix.dm"
 #include "code\__HELPERS\matrices\transform_matrix.dm"