elementize pet collars (#29209)

code/__DEFINES/dcs/mob_signals.dm

@@ -196,6 +196,7 @@
 
 ///from of mob/MouseDrop(): (/atom/over, /mob/user)
 #define COMSIG_DO_MOB_STRIP "do_mob_strip"
+#define COMSIG_STRIPPABLE_REQUEST_ITEMS "strippable_request_items"
 
 // Sent when a mob spawner is attacked directly or via projectile.
 #define COMSIG_SPAWNER_SET_TARGET "spawner_set_target"
@@ -239,3 +240,5 @@
 	#define MOVE_ARG_NEW_LOC 1
 	/// The arugment of move_args which dictates our movement direction
 	#define MOVE_ARG_DIRECTION 2
+
+#define COMSIG_LIVING_RESTING "living_resting"

code/datums/elements/strippable.dm

@@ -313,8 +313,11 @@
 
 	var/list/items = list()
 
-	for(var/strippable_key in strippable.items)
-		var/datum/strippable_item/item_data = strippable.items[strippable_key]
+	var/list/unfiltered_items = strippable.items.Copy()
+	SEND_SIGNAL(owner, COMSIG_STRIPPABLE_REQUEST_ITEMS, unfiltered_items)
+
+	for(var/strippable_key in unfiltered_items)
+		var/datum/strippable_item/item_data = unfiltered_items[strippable_key]
 
 		if(!item_data.should_show(owner, user))
 			continue
@@ -389,11 +392,14 @@
 	if(!isliving(ui.user) || !HAS_TRAIT(user, TRAIT_CAN_STRIP))
 		return
 
+	var/list/unfiltered_items = strippable.items.Copy()
+	SEND_SIGNAL(owner, COMSIG_STRIPPABLE_REQUEST_ITEMS, unfiltered_items)
+
 	. = TRUE
 	switch(action)
 		if("use")
 			var/key = params["key"]
-			var/datum/strippable_item/strippable_item = strippable.items[key]
+			var/datum/strippable_item/strippable_item = unfiltered_items[key]
 
 			if(isnull(strippable_item))
 				return

code/datums/elements/wears_collar.dm

@@ -0,0 +1,122 @@
+/datum/element/wears_collar
+	element_flags = ELEMENT_BESPOKE
+	argument_hash_start_idx = 2
+	///our icon's pathfile
+	var/collar_icon
+	///our collar's icon state
+	var/collar_icon_state
+	///iconstate of our collar while resting
+	var/collar_resting_icon_state
+
+	var/datum/strippable_item/pet_collar/pet_collar
+
+/datum/element/wears_collar/Attach(datum/target, collar_icon_ = 'icons/mob/pets.dmi', collar_icon_state_, collar_resting_icon_state_ = FALSE)
+	. = ..()
+
+	if(!isliving(target))
+		return ELEMENT_INCOMPATIBLE
+
+	collar_icon = collar_icon_
+	collar_icon_state = collar_icon_state_
+	collar_resting_icon_state = collar_resting_icon_state_
+	pet_collar = new
+
+	RegisterSignal(target, COMSIG_ATTACK_BY, PROC_REF(attach_collar))
+	RegisterSignal(target, COMSIG_ATOM_UPDATE_OVERLAYS, PROC_REF(on_overlays_updated))
+	RegisterSignal(target, COMSIG_ATOM_EXITED, PROC_REF(on_content_exit))
+	RegisterSignal(target, COMSIG_ATOM_ENTERED, PROC_REF(on_content_enter))
+	RegisterSignal(target, COMSIG_LIVING_RESTING, PROC_REF(on_rest))
+	RegisterSignal(target, COMSIG_MOB_STATCHANGE, PROC_REF(on_stat_change))
+	RegisterSignal(target, COMSIG_STRIPPABLE_REQUEST_ITEMS, PROC_REF(on_strippable_request_items))
+
+/datum/element/wears_collar/Detach(datum/target)
+	. = ..()
+	UnregisterSignal(target, list(
+		COMSIG_ATTACK_BY,
+		COMSIG_ATOM_UPDATE_OVERLAYS,
+		COMSIG_ATOM_EXITED,
+		COMSIG_ATOM_ENTERED,
+		COMSIG_LIVING_RESTING,
+		COMSIG_MOB_STATCHANGE,
+		COMSIG_STRIPPABLE_REQUEST_ITEMS,
+	))
+
+/datum/element/wears_collar/proc/on_strippable_request_items(datum/source, list/items)
+	SIGNAL_HANDLER // COMSIG_STRIPPABLE_REQUEST_ITEMS
+	items[STRIPPABLE_ITEM_PET_COLLAR] = pet_collar
+
+/datum/element/wears_collar/proc/on_stat_change(mob/living/source)
+	SIGNAL_HANDLER // COMSIG_MOB_STATCHANGE
+
+	if(collar_icon_state)
+		source.update_icon(UPDATE_OVERLAYS)
+
+/datum/element/wears_collar/proc/on_content_exit(mob/living/source, atom/moved)
+	SIGNAL_HANDLER // COMSIG_ATOM_EXITED
+
+	var/obj/item/petcollar/collar = moved
+	if(!istype(moved))
+		return
+
+	if(collar.tagname)
+		source.name = collar.original_name
+		source.real_name = collar.original_real_name
+
+	collar.original_name = null
+	collar.original_real_name = null
+
+	if(collar_icon_state)
+		source.update_appearance()
+
+/datum/element/wears_collar/proc/on_content_enter(mob/living/source, obj/item/petcollar/new_collar)
+	SIGNAL_HANDLER // COMSIG_ATOM_ENTERED
+
+	if(!istype(new_collar))
+		return
+
+	if(new_collar.tagname)
+		new_collar.original_name = source.name
+		new_collar.original_real_name = source.real_name
+		source.name = new_collar.tagname
+		source.real_name = new_collar.tagname
+
+	if(collar_icon_state)
+		source.update_appearance()
+
+/datum/element/wears_collar/proc/attach_collar(atom/source, atom/movable/attacking_item, mob/user, params)
+	SIGNAL_HANDLER // COMSIG_ATTACK_BY
+
+	if(!istype(attacking_item, /obj/item/petcollar))
+		return NONE
+	if(locate(/obj/item/petcollar) in source)
+		to_chat(user, "<span class='warning'>[source] is already wearing a collar!</span>")
+		return COMPONENT_SKIP_AFTERATTACK
+
+	if(user.drop_item())
+		attacking_item.forceMove(source)
+		to_chat(user, "<span class='notice'>You put [attacking_item] around [source]'s neck.</span>")
+	else
+		to_chat(user, "<span class='warning'>[attacking_item] is stuck to your hand!</span>")
+
+	return COMPONENT_SKIP_AFTERATTACK
+
+/datum/element/wears_collar/proc/on_overlays_updated(mob/living/source, list/overlays)
+	SIGNAL_HANDLER // COMSIG_ATOM_UPDATE_OVERLAYS
+
+	if(!locate(/obj/item/petcollar) in source)
+		return
+
+	var/icon_tag = ""
+
+	if(source.stat == DEAD || HAS_TRAIT(source, TRAIT_FAKEDEATH))
+		icon_tag = "_dead"
+	else if(collar_resting_icon_state && source.resting)
+		icon_tag =  "_rest"
+
+	overlays += mutable_appearance(collar_icon, "[collar_icon_state][icon_tag]collar")
+	overlays += mutable_appearance(collar_icon, "[collar_icon_state][icon_tag]tag")
+
+/datum/element/wears_collar/proc/on_rest(atom/movable/source)
+	SIGNAL_HANDLER // COMSIG_LIVING_RESTING
+
+	source.update_icon(UPDATE_OVERLAYS)

code/game/objects/items/collar.dm

@@ -4,6 +4,8 @@
 	icon_state = "petcollar"
 	item_color = "petcollar"
 	var/tagname = null
+	var/original_name
+	var/original_real_name
 	var/obj/item/card/id/access_id
 
 /obj/item/petcollar/Destroy()
@@ -62,7 +64,7 @@
 /obj/item/petcollar/process()
 	var/mob/living/simple_animal/M = loc
 	// if it wasn't intentionally unequipped but isn't being worn, possibly gibbed
-	if(istype(M) && src == M.pcollar && M.stat != DEAD)
+	if(istype(M) && M.stat != DEAD)
 		return
 
 	var/area/pet_death_area = get_area(M)

code/modules/admin/topic.dm

@@ -2093,10 +2093,9 @@
 					P.master_commander = H
 					P.universal_speak = TRUE
 					P.universal_understand = TRUE
-					P.set_can_collar(TRUE)
+					P.AddElement(/datum/element/wears_collar)
 					P.faction = list("neutral")
-					var/obj/item/petcollar/C = new
-					P.add_collar(C)
+					var/obj/item/petcollar/C = new(P)
 					var/obj/item/card/id/I = H.wear_id
 					if(I)
 						var/obj/item/card/id/D = new /obj/item/card/id(C)

code/modules/events/sentience.dm

@@ -27,7 +27,7 @@
 	dust_if_respawnable(SG)
 	SA.universal_speak = TRUE
 	SA.sentience_act()
-	SA.set_can_collar(TRUE)
+	SA.AddElement(/datum/element/wears_collar)
 	SA.maxHealth = max(SA.maxHealth, 200)
 	SA.health = SA.maxHealth
 	SA.del_on_death = FALSE

code/modules/mining/equipment/lazarus_injector.dm

@@ -27,7 +27,7 @@
 			if(M.stat == DEAD)
 				M.faction = list("neutral")
 				M.revive()
-				M.set_can_collar(TRUE)
+				M.AddElement(/datum/element/wears_collar)
 				if(ishostile(target))
 					var/mob/living/simple_animal/hostile/H = M
 					if(isretaliate(target))

code/modules/mob/living/living_status_procs.dm

@@ -120,6 +120,7 @@ STATUS EFFECTS
 			layer = LYING_MOB_LAYER //so mob lying always appear behind standing mobs
 	ADD_TRAIT(src, TRAIT_UI_BLOCKED, LYING_DOWN_TRAIT)
 	ADD_TRAIT(src, TRAIT_CANNOT_PULL, LYING_DOWN_TRAIT)
+	SEND_SIGNAL(src, COMSIG_LIVING_RESTING, TRUE)
 	RegisterSignal(src, COMSIG_ATOM_DIR_CHANGE, PROC_REF(orient_crawling))
 	set_density(FALSE)
 	set_lying_angle(pick(90, 270))
@@ -129,6 +130,7 @@ STATUS EFFECTS
 		layer = initial(layer)
 	set_density(initial(density))
 	REMOVE_TRAITS_IN(src, LYING_DOWN_TRAIT)
+	SEND_SIGNAL(src, COMSIG_LIVING_RESTING, FALSE)
 	UnregisterSignal(src, COMSIG_ATOM_DIR_CHANGE)
 	set_lying_angle(0)
 	pixel_y = 0

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

@@ -1,8 +1,3 @@
-/mob/living/simple_animal/item_interaction(mob/living/user, obj/item/O, list/modifiers)
-	if(can_collar && istype(O, /obj/item/petcollar) && !pcollar)
-		add_collar(O, user)
-		return ITEM_INTERACT_COMPLETE
-
 /mob/living/simple_animal/attack_hand(mob/living/carbon/human/M)
 	..()
 	switch(M.a_intent)

code/modules/mob/living/simple_animal/friendly/bunny.dm

@@ -25,10 +25,13 @@
 	maxbodytemp = 323	//Above 50 Degrees Celcius
 	can_hide = TRUE
 	holder_type = /obj/item/holder/bunny
-	can_collar = TRUE
 	gold_core_spawnable = FRIENDLY_SPAWN
 	ventcrawler = VENTCRAWLER_ALWAYS
 
+/mob/living/simple_animal/bunny/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /mob/living/simple_animal/bunny/attack_hand(mob/living/carbon/human/M)
 	if(M.a_intent == INTENT_HELP)
 		get_scooped(M, TRUE)

code/modules/mob/living/simple_animal/friendly/cat.dm

@@ -22,12 +22,16 @@
 	response_disarm = "gently pushes aside"
 	response_harm   = "kicks"
 	gold_core_spawnable = FRIENDLY_SPAWN
-	collar_type = "cat"
 	var/turns_since_scan = 0
 	var/mob/living/simple_animal/mouse/movement_target
 	var/eats_mice = 1
+	var/collar_icon_state = "cat"
 	footstep_type = FOOTSTEP_MOB_CLAW
 
+/mob/living/simple_animal/pet/cat/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar, collar_icon_state_ = collar_icon_state, collar_resting_icon_state_ = TRUE)
+
 //RUNTIME IS ALIVE! SQUEEEEEEEE~
 /mob/living/simple_animal/pet/cat/runtime
 	name = "Runtime"
@@ -118,7 +122,6 @@
 	resting = TRUE
 	custom_emote(EMOTE_VISIBLE, pick("sits down.", "crouches on its hind legs.", "looks alert."))
 	icon_state = "[icon_living]_sit"
-	collar_type = "[initial(collar_type)]_sit"
 
 /mob/living/simple_animal/pet/cat/handle_automated_action()
 	if(stat == CONSCIOUS && !buckled)
@@ -195,7 +198,7 @@
 	gender = NEUTER
 	density = FALSE
 	pass_flags = PASSMOB
-	collar_type = "kitten"
+	collar_icon_state = "kitten"
 
 /mob/living/simple_animal/pet/cat/syndi
 	name = "SyndiCat"

code/modules/mob/living/simple_animal/friendly/corgi_stripping.dm

@@ -2,8 +2,7 @@
 
 GLOBAL_LIST_INIT(strippable_corgi_items, create_strippable_list(list(
 	/datum/strippable_item/corgi_head,
-	/datum/strippable_item/corgi_back,
-	/datum/strippable_item/pet_collar
+	/datum/strippable_item/corgi_back
 )))
 
 /datum/strippable_item/corgi_head
@@ -41,7 +40,7 @@ GLOBAL_LIST_INIT(strippable_corgi_items, create_strippable_list(list(
 	if(!istype(pet_source))
 		return
 
-	return pet_source.pcollar
+	return (locate(/obj/item/petcollar) in source)
 
 /datum/strippable_item/pet_collar/try_equip(atom/source, obj/item/equipping, mob/user)
 	. = ..()
@@ -59,15 +58,15 @@ GLOBAL_LIST_INIT(strippable_corgi_items, create_strippable_list(list(
 	if(!istype(pet_source))
 		return
 
-	INVOKE_ASYNC(source, TYPE_PROC_REF(/mob/living/simple_animal, add_collar), equipping, user)
+	user.transfer_item_to(equipping, source)
 
 /datum/strippable_item/pet_collar/finish_unequip(atom/source, mob/user)
 	var/mob/living/simple_animal/pet_source = source
 	if(!istype(pet_source))
 		return
 
-	INVOKE_ASYNC(pet_source, TYPE_PROC_REF(/mob/living/simple_animal, remove_collar), user.drop_location(), user)
-
+	var/obj/item/petcollar/collar = locate() in source
+	user.put_in_hands(collar)
 
 /datum/strippable_item/corgi_back
 	key = STRIPPABLE_ITEM_BACK

code/modules/mob/living/simple_animal/friendly/crab.dm

@@ -18,9 +18,12 @@
 	friendly = "pinches"
 	ventcrawler = VENTCRAWLER_ALWAYS
 	can_hide = TRUE
-	can_collar = TRUE
 	gold_core_spawnable = FRIENDLY_SPAWN
 
+/mob/living/simple_animal/crab/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /mob/living/simple_animal/crab/handle_automated_movement()
 	//CRAB movement
 	if(stat == CONSCIOUS || !isturf(loc) || IS_HORIZONTAL(src) || buckled)

code/modules/mob/living/simple_animal/friendly/deer.dm

@@ -15,6 +15,9 @@
 	response_help = "pets"
 	response_disarm = "gently pushes aside"
 	response_harm = "kicks"
-	can_collar = TRUE
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST
 	gold_core_spawnable = FRIENDLY_SPAWN
+
+/mob/living/simple_animal/deer/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)

code/modules/mob/living/simple_animal/friendly/diona_nymph.dm

@@ -43,7 +43,6 @@
 
 	var/list/donors = list()
 	holder_type = /obj/item/holder/diona
-	can_collar = TRUE
 
 	a_intent = INTENT_HELP
 	var/evolve_donors = 5 //amount of blood donors needed before evolving
@@ -54,6 +53,10 @@
 	var/datum/action/innate/diona/evolve/evolve_action = new()
 	var/datum/action/innate/diona/steal_blood/steal_blood_action = new()
 
+/mob/living/simple_animal/diona/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /datum/action/innate/diona/merge
 	name = "Merge with gestalt"
 	button_overlay_icon = 'icons/mob/human_races/r_diona.dmi'

code/modules/mob/living/simple_animal/friendly/dog.dm

@@ -73,7 +73,6 @@
 	butcher_results = list(/obj/item/food/meat/corgi = 3, /obj/item/stack/sheet/animalhide/corgi = 1)
 	childtype = list(/mob/living/simple_animal/pet/dog/corgi/puppy = 95, /mob/living/simple_animal/pet/dog/corgi/puppy/void = 5)
 	animal_species = /mob/living/simple_animal/pet/dog
-	collar_type = "corgi"
 	hud_type = /datum/hud/corgi
 	///Currently worn item on the head slot
 	var/obj/item/inventory_head = null
@@ -84,13 +83,14 @@
 	var/shaved = FALSE
 	var/nofur = FALSE 		//Corgis that have risen past the material plane of existence.
 	var/razor_shave_delay = 5 SECONDS
+	var/collar_icon_state = "corgi"
+
 
 /mob/living/simple_animal/pet/dog/corgi/Initialize(mapload)
 	. = ..()
-	regenerate_icons()
-
-/mob/living/simple_animal/pet/dog/corgi/add_strippable_element()
+	AddElement(/datum/element/wears_collar, collar_icon_state_ = collar_icon_state)
 	AddElement(/datum/element/strippable, length(strippable_inventory_slots) ? create_strippable_list(strippable_inventory_slots) : GLOB.strippable_corgi_items)
+	regenerate_icons()
 
 /mob/living/simple_animal/pet/dog/corgi/Destroy()
 	QDEL_NULL(inventory_head)
@@ -246,7 +246,7 @@
 		item_to_add.forceMove(src)
 		inventory_head = item_to_add
 		update_corgi_fluff()
-		regenerate_icons()
+		update_appearance()
 	else
 		to_chat(user, "<span class='warning'>You set [item_to_add] on [src]'s head, but it falls off!</span>")
 		item_to_add.forceMove(drop_location())
@@ -276,8 +276,9 @@
 		var/datum/dog_fashion/DF = new inventory_back.dog_fashion(src)
 		DF.apply(src)
 
-/mob/living/simple_animal/pet/dog/corgi/regenerate_icons()
-	..()
+/mob/living/simple_animal/pet/dog/corgi/update_overlays()
+	. = ..()
+
 	if(inventory_head)
 		var/image/head_icon
 		var/datum/dog_fashion/DF = new inventory_head.dog_fashion(src)
@@ -296,7 +297,7 @@
 		else
 			head_icon = DF.get_overlay()
 
-		add_overlay(head_icon)
+		. += head_icon
 
 	if(inventory_back)
 		var/image/back_icon
@@ -315,7 +316,8 @@
 			back_icon.transform = turn(back_icon.transform, 180)
 		else
 			back_icon = DF.get_overlay()
-		add_overlay(back_icon)
+
+		. += back_icon
 
 //IAN! SQUEEEEEEEEE~
 /mob/living/simple_animal/pet/dog/corgi/ian
@@ -519,9 +521,8 @@
 	density = FALSE
 	pass_flags = PASSMOB
 	mob_size = MOB_SIZE_SMALL
-	collar_type = "puppy"
-	strippable_inventory_slots = list(/datum/strippable_item/pet_collar) // Puppies do not have a head or back equipment slot.
-
+	strippable_inventory_slots = list() // Puppies do not have a head or back equipment slot.
+	collar_icon_state = "puppy"
 
 /// Tribute to the corgis born in nullspace
 /mob/living/simple_animal/pet/dog/corgi/puppy/void
@@ -553,7 +554,7 @@
 	response_help  = "pets"
 	response_disarm = "bops"
 	response_harm   = "kicks"
-	strippable_inventory_slots = list(/datum/strippable_item/corgi_back, /datum/strippable_item/pet_collar) //Lisa already has a cute bow!
+	strippable_inventory_slots = list(/datum/strippable_item/corgi_back) //Lisa already has a cute bow!
 	var/turns_since_scan = 0
 
 /mob/living/simple_animal/pet/dog/corgi/lisa/Life()
@@ -655,7 +656,10 @@
 	icon_living = "pug"
 	icon_dead = "pug_dead"
 	butcher_results = list(/obj/item/food/meat/pug = 3)
-	collar_type = "pug"
+
+/mob/living/simple_animal/pet/dog/pug/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar, collar_icon_state_ = "pug")
 
 /mob/living/simple_animal/pet/dog/pug/handle_automated_movement()
 	. = ..()

code/modules/mob/living/simple_animal/friendly/farm_animals.dm

@@ -26,7 +26,6 @@
 	melee_damage_lower = 1
 	melee_damage_upper = 2
 	stop_automated_movement_when_pulled = TRUE
-	can_collar = TRUE
 	blood_volume = BLOOD_VOLUME_NORMAL
 	var/obj/item/udder/cow/udder = null
 	gender = FEMALE
@@ -35,6 +34,7 @@
 /mob/living/simple_animal/hostile/retaliate/goat/Initialize(mapload)
 	. = ..()
 	udder = new()
+	AddElement(/datum/element/wears_collar)
 
 /mob/living/simple_animal/hostile/retaliate/goat/Destroy()
 	QDEL_NULL(udder)
@@ -135,12 +135,12 @@
 	mob_size = MOB_SIZE_TINY
 	holder_type = /obj/item/holder/chicken
 	can_hide = TRUE
-	can_collar = TRUE
 	gold_core_spawnable = FRIENDLY_SPAWN
 	footstep_type = FOOTSTEP_MOB_CLAW
 
 /mob/living/simple_animal/chick/Initialize(mapload)
 	. = ..()
+	AddElement(/datum/element/wears_collar)
 	scatter_atom()
 
 /mob/living/simple_animal/chick/scatter_atom(x_offset, y_offset)
@@ -157,10 +157,10 @@
 				C.name = name
 			if(mind)
 				mind.transfer_to(C)
-			if(pcollar)
-				var/the_collar = pcollar
-				drop_item_to_ground(pcollar)
-				C.add_collar(the_collar)
+
+			for(var/atom/movable/AM in contents)
+				AM.forceMove(C)
+
 			qdel(src)
 
 
@@ -208,7 +208,6 @@ GLOBAL_VAR_INIT(chicken_count, 0)
 	mob_size = MOB_SIZE_SMALL
 	holder_type = /obj/item/holder/chicken
 	can_hide = TRUE
-	can_collar = TRUE
 	var/list/feedMessages = list("It clucks happily.","It clucks happily.")
 	var/list/layMessage = EGG_LAYING_MESSAGES
 	var/list/validColors = list("brown","black","white")
@@ -222,6 +221,7 @@ GLOBAL_VAR_INIT(chicken_count, 0)
 	icon_state = "[icon_prefix]_[body_color]"
 	icon_living = "[icon_prefix]_[body_color]"
 	icon_dead = "[icon_prefix]_[body_color]_dead"
+	AddElement(/datum/element/wears_collar)
 	scatter_atom()
 	update_appearance(UPDATE_ICON_STATE)
 	GLOB.chicken_count += 1
@@ -325,11 +325,14 @@ GLOBAL_VAR_INIT(chicken_count, 0)
 	attacktext = "pecks"
 	health = 50
 	maxHealth = 50
-	can_collar = TRUE
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST
 	gold_core_spawnable = FRIENDLY_SPAWN
 	footstep_type = FOOTSTEP_MOB_CLAW
 
+/mob/living/simple_animal/turkey/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /mob/living/simple_animal/goose
 	name = "goose"
 	desc = "A pretty goose. Would make a nice comforter."
@@ -350,11 +353,14 @@ GLOBAL_VAR_INIT(chicken_count, 0)
 	attacktext = "kicks"
 	health = 50
 	maxHealth = 50
-	can_collar = TRUE
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST
 	gold_core_spawnable = FRIENDLY_SPAWN
 	footstep_type = FOOTSTEP_MOB_CLAW
 
+/mob/living/simple_animal/goose/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /mob/living/simple_animal/seal
 	name = "seal"
 	desc = "A beautiful white seal."
@@ -375,11 +381,14 @@ GLOBAL_VAR_INIT(chicken_count, 0)
 	attacktext = "kicks"
 	health = 50
 	maxHealth = 50
-	can_collar = TRUE
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST
 	gold_core_spawnable = FRIENDLY_SPAWN
 	blood_volume = BLOOD_VOLUME_NORMAL
 
+/mob/living/simple_animal/seal/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /mob/living/simple_animal/walrus
 	name = "walrus"
 	desc = "A big brown walrus."
@@ -400,11 +409,14 @@ GLOBAL_VAR_INIT(chicken_count, 0)
 	attacktext = "kicks"
 	health = 50
 	maxHealth = 50
-	can_collar = TRUE
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST
 	gold_core_spawnable = FRIENDLY_SPAWN
 	blood_volume = BLOOD_VOLUME_NORMAL
 
+/mob/living/simple_animal/walrus/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /obj/item/udder
 	name = "udder"
 

code/modules/mob/living/simple_animal/friendly/lizard.dm

@@ -23,13 +23,16 @@
 	can_hide = TRUE
 	pass_door_while_hidden = TRUE
 	butcher_results = list(/obj/item/food/meat = 1)
-	can_collar = TRUE
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST | MOB_REPTILE
 	gold_core_spawnable = FRIENDLY_SPAWN
 	var/eating_sound = 'sound/weapons/bite.ogg'
 	/// Lizards start with a tail
 	var/has_tail = TRUE
 
+/mob/living/simple_animal/lizard/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
+
 /mob/living/simple_animal/lizard/handle_automated_action()
 	if(stat == CONSCIOUS && !buckled)
 		if(prob(1))

code/modules/mob/living/simple_animal/friendly/mouse.dm

@@ -34,12 +34,12 @@
 	can_hide = TRUE
 	pass_door_while_hidden = TRUE
 	holder_type = /obj/item/holder/mouse
-	can_collar = TRUE
 	gold_core_spawnable = FRIENDLY_SPAWN
 	var/chew_probability = 1
 
 /mob/living/simple_animal/mouse/Initialize(mapload)
 	. = ..()
+	AddElement(/datum/element/wears_collar)
 	AddComponent(/datum/component/squeak, list('sound/creatures/mousesqueak.ogg' = 1), 100, extrarange = SHORT_RANGE_SOUND_EXTRARANGE) //as quiet as a mouse or whatever
 
 /mob/living/simple_animal/mouse/handle_automated_action()

code/modules/mob/living/simple_animal/friendly/nian_caterpillar.dm

@@ -41,7 +41,6 @@
 	attack_sound = 'sound/weapons/bite.ogg'
 
 	holder_type = /obj/item/holder/nian_caterpillar
-	can_collar = TRUE
 
 	/// Evolution action.
 	var/datum/action/innate/nian_caterpillar_emerge/evolve_action = new()
@@ -51,6 +50,7 @@
 /mob/living/simple_animal/nian_caterpillar/Initialize(mapload)
 	. = ..()
 	real_name = name
+	AddElement(/datum/element/wears_collar)
 	add_language("Tkachi")
 	evolve_action.Grant(src)
 

code/modules/mob/living/simple_animal/friendly/penguin.dm

@@ -19,6 +19,7 @@
 
 /mob/living/simple_animal/pet/penguin/Initialize(mapload)
 	. = ..()
+	AddElement(/datum/element/wears_collar)
 	AddElement(/datum/element/waddling)
 
 /mob/living/simple_animal/pet/penguin/emperor

code/modules/mob/living/simple_animal/friendly/pet.dm

@@ -3,7 +3,6 @@
 	mob_size = MOB_SIZE_SMALL
 	mob_biotypes = MOB_ORGANIC | MOB_BEAST
 	blood_volume = BLOOD_VOLUME_NORMAL
-	can_collar = TRUE
 	speed = 0 // same speed as a person.
 	hud_type = /datum/hud/corgi
 

code/modules/mob/living/simple_animal/friendly/sloth.dm

@@ -25,6 +25,9 @@
 	speed = 2
 	footstep_type = FOOTSTEP_MOB_CLAW
 
+/mob/living/simple_animal/pet/sloth/Initialize(mapload)
+	. = ..()
+	AddElement(/datum/element/wears_collar)
 
 //IAA Sloth
 /mob/living/simple_animal/pet/sloth/paperwork

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

@@ -33,7 +33,6 @@
 	icon_dead = "parrot_dead"
 	icon_resting = "parrot_sit"
 	pass_flags = PASSTABLE
-	can_collar = TRUE
 	blocks_emissive = EMISSIVE_BLOCK_UNIQUE
 	faction = list("neutral", "jungle")
 
@@ -127,7 +126,7 @@
 		/obj/machinery/computer/guestpass
 	))
 
-/mob/living/simple_animal/parrot/add_strippable_element()
+	AddElement(/datum/element/wears_collar)
 	AddElement(/datum/element/strippable, GLOB.strippable_parrot_items)
 
 /mob/living/simple_animal/parrot/Destroy()

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

@@ -1,6 +1,5 @@
 GLOBAL_LIST_INIT(strippable_parrot_items, create_strippable_list(list(
 	/datum/strippable_item/parrot_headset,
-	/datum/strippable_item/pet_collar
 )))
 
 /datum/strippable_item/parrot_headset

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

@@ -87,13 +87,8 @@
 	/// Allows a mob to pass unbolted doors while hidden
 	var/pass_door_while_hidden = FALSE
 
-	var/obj/item/petcollar/pcollar = null
-	/// If the mob has collar sprites, define them.
-	var/collar_type
 	/// If the mob can be renamed
 	var/unique_pet = FALSE
-	/// Can add collar to mob or not, use the set_can_collar if you want to change this on runtime
-	var/can_collar = FALSE
 
 	/// Hot simple_animal baby making vars
 	var/list/childtype = null
@@ -152,12 +147,8 @@
 	if(can_hide)
 		var/datum/action/innate/hide/hide = new()
 		hide.Grant(src)
-	if(pcollar)
-		pcollar = new(src)
-		regenerate_icons()
 	if(footstep_type)
 		AddComponent(/datum/component/footstep, footstep_type)
-	add_strippable_element()
 
 	apply_atmos_requirements()
 	AddElement(/datum/element/body_temperature, minbodytemp, maxbodytemp, cold_damage_per_tick, heat_damage_per_tick)
@@ -165,7 +156,6 @@
 /mob/living/simple_animal/Destroy()
 	/// We need to clear the reference to where we're walking to properly GC
 	GLOB.move_manager.stop_looping(src)
-	QDEL_NULL(pcollar)
 	for(var/datum/action/innate/hide/hide in actions)
 		hide.Remove(src)
 	master_commander = null
@@ -200,11 +190,6 @@
 /mob/living/simple_animal/proc/remove_atmos_requirements()
 	RemoveElement(/datum/element/atmos_requirements)
 
-/mob/living/simple_animal/handle_atom_del(atom/A)
-	if(A == pcollar)
-		pcollar = null
-	return ..()
-
 /mob/living/simple_animal/examine(mob/user)
 	. = ..()
 	if(stat == DEAD)
@@ -222,9 +207,6 @@
 	..()
 	if(icon_resting && stat != DEAD)
 		icon_state = icon_resting
-		if(collar_type)
-			collar_type = "[initial(collar_type)]_rest"
-			regenerate_icons()
 	if(!can_crawl)
 		ADD_TRAIT(src, TRAIT_IMMOBILIZED, LYING_DOWN_TRAIT) //simple mobs cannot crawl (unless they can)
 
@@ -232,9 +214,6 @@
 	..()
 	if(icon_resting && stat != DEAD)
 		icon_state = icon_living
-		if(collar_type)
-			collar_type = "[initial(collar_type)]"
-			regenerate_icons()
 
 /mob/living/simple_animal/update_stat(reason = "none given")
 	if(status_flags & GODMODE)
@@ -316,10 +295,8 @@
 		for(var/path in butcher_results)
 			for(var/i in 1 to butcher_results[path])
 				new path(Tsec)
-	if(pcollar)
-		pcollar.forceMove(drop_location())
-		pcollar = null
 	..()
+
 /mob/living/simple_animal/say_quote(message)
 	var/verb = "says"
 
@@ -353,9 +330,6 @@
 	density = initial(density)
 	if(TRAIT_FLYING in initial_traits)
 		ADD_TRAIT(src, TRAIT_FLYING, INNATE_TRAIT)
-	if(collar_type)
-		collar_type = "[initial(collar_type)]"
-		regenerate_icons()
 
 /mob/living/simple_animal/death(gibbed)
 	// Only execute the below if we successfully died
@@ -389,9 +363,6 @@
 		if(flip_on_death)
 			transform = transform.Turn(180)
 		density = FALSE
-		if(collar_type)
-			collar_type = "[initial(collar_type)]_dead"
-			regenerate_icons()
 
 /mob/living/simple_animal/proc/CanAttack(atom/the_target)
 	if(see_invisible < the_target.invisibility)
@@ -472,20 +443,11 @@
 /mob/living/simple_animal/get_item_by_slot(slot_id)
 	switch(slot_id)
 		if(ITEM_SLOT_COLLAR)
-			return pcollar
+			return (locate(/obj/item/petcollar) in src)
 	. = ..()
 
 /mob/living/simple_animal/can_equip(obj/item/I, slot, disable_warning = 0)
-	// . = ..() // Do not call parent. We do not want animals using their hand slots.
-	switch(slot)
-		if(ITEM_SLOT_COLLAR)
-			if(pcollar)
-				return FALSE
-			if(!can_collar)
-				return FALSE
-			if(!istype(I, /obj/item/petcollar))
-				return FALSE
-			return TRUE
+	return FALSE
 
 /mob/living/simple_animal/equip_to_slot(obj/item/W, slot, initial = FALSE)
 	if(!istype(W))
@@ -497,23 +459,15 @@
 	W.layer = ABOVE_HUD_LAYER
 	W.plane = ABOVE_HUD_PLANE
 
-	switch(slot)
-		if(ITEM_SLOT_COLLAR)
-			add_collar(W)
-
 /mob/living/simple_animal/unequip_to(obj/item/target, atom/destination, force = FALSE, silent = FALSE, drop_inventory = TRUE, no_move = FALSE)
 	. = ..()
 	if(!. || !target)
 		return
 
-	if(target == pcollar)
-		pcollar = null
-		regenerate_icons()
-
 /mob/living/simple_animal/get_access()
 	. = ..()
-	if(pcollar)
-		. |= pcollar.GetAccess()
+	for(var/obj/item/petcollar/collar in contents)
+		. |= collar.GetAccess()
 
 /mob/living/simple_animal/update_transform()
 	var/matrix/ntransform = matrix(transform) //aka transform.Copy()
@@ -587,41 +541,6 @@
 		LAZYREMOVE(idle_mobs_on_old_z, src)
 		toggle_ai(initial(AIStatus))
 
-/mob/living/simple_animal/proc/add_collar(obj/item/petcollar/P, mob/user)
-	if(!istype(P) || QDELETED(P) || pcollar)
-		return
-	if(user && !user.drop_item_to_ground(P))
-		return
-	P.forceMove(src)
-	P.equipped(src)
-	pcollar = P
-	regenerate_icons()
-	if(user)
-		to_chat(user, "<span class='notice'>You put [P] around [src]'s neck.</span>")
-	if(P.tagname && !unique_pet)
-		name = P.tagname
-		real_name = P.tagname
-
-/mob/living/simple_animal/proc/remove_collar(atom/new_loc, mob/user)
-	if(!pcollar)
-		return
-
-	var/obj/old_collar = pcollar
-
-	drop_item_to_ground(pcollar)
-
-	if(user)
-		user.put_in_hands(old_collar)
-
-	return old_collar
-
-
-/mob/living/simple_animal/regenerate_icons()
-	cut_overlays()
-	if(pcollar && collar_type)
-		add_overlay("[collar_type]collar")
-		add_overlay("[collar_type]tag")
-
 /mob/living/simple_animal/Login()
 	..()
 	GLOB.move_manager.stop_looping(src) // if mob is moving under ai control, then stop AI movement
@@ -639,16 +558,3 @@
 
 /mob/living/simple_animal/proc/end_dchat_plays()
 	stop_automated_movement = FALSE
-
-/mob/living/simple_animal/proc/set_can_collar(new_value)
-	can_collar = (new_value ? TRUE : FALSE)
-	if(can_collar)
-		add_strippable_element()
-		return
-	remove_collar(drop_location())
-	RemoveElement(/datum/element/strippable)
-
-/mob/living/simple_animal/proc/add_strippable_element()
-	if(!can_collar)
-		return
-	AddElement(/datum/element/strippable, create_strippable_list(list(/datum/strippable_item/pet_collar)))

code/modules/mob/mob_misc_procs.dm

@@ -5,13 +5,6 @@
 			return 1
 	return 0
 
-/proc/ispet(A)
-	if(isanimal(A))
-		var/mob/living/simple_animal/SA = A
-		if(SA.can_collar)
-			return 1
-	return 0
-
 /mob/proc/get_screen_colour()
 	SHOULD_CALL_PARENT(TRUE)
 	// OOC Colourblind setting takes priority over everything else.

code/modules/research/xenobiology/xenobiology.dm

@@ -253,7 +253,7 @@
 		SM.faction = user.faction
 		SM.master_commander = user
 		SM.sentience_act()
-		SM.set_can_collar(TRUE)
+		SM.AddElement(/datum/element/wears_collar)
 		to_chat(SM, "<span class='warning'>All at once it makes sense: you know what you are and who you are! Self awareness is yours!</span>")
 		to_chat(SM, "<span class='userdanger'>You are grateful to be self aware and owe [user] a great debt. Serve [user], and assist [user.p_them()] in completing [user.p_their()] goals at any cost.</span>")
 		if(SM.flags_2 & HOLOGRAM_2) //Check to see if it's a holodeck creature
@@ -322,7 +322,7 @@
 	SM.universal_speak = TRUE
 	SM.faction = user.faction
 	SM.sentience_act() //Same deal here as with sentience
-	SM.set_can_collar(TRUE)
+	SM.AddElement(/datum/element/wears_collar)
 	user.death()
 	to_chat(SM, "<span class='notice'>In a quick flash, you feel your consciousness flow into [SM]!</span>")
 	to_chat(SM, "<span class='warning'>You are now [SM]. Your allegiances, alliances, and roles are still the same as they were prior to consciousness transfer!</span>")

code/tests/game_tests.dm

@@ -47,6 +47,7 @@
 #include "test_subsystem_init.dm"
 #include "test_subsystem_metric_sanity.dm"
 #include "test_timer_sanity.dm"
+#include "test_wears_collar.dm"
 #endif
 
 #ifdef MAP_TESTS

code/tests/test_wears_collar.dm

@@ -0,0 +1,24 @@
+/datum/game_test/wears_collar/Run()
+	var/datum/test_puppeteer/player = new(src)
+
+	var/obj/chair = player.spawn_obj_nearby(/obj/structure/chair)
+	var/mob/corgi = player.spawn_mob_nearby(/mob/living/simple_animal/pet/dog/corgi)
+	chair.buckle_mob(corgi) // So it doesn't wander off
+
+	var/obj/item/petcollar/collar = player.spawn_obj_in_hand(/obj/item/petcollar)
+	player.click_on(corgi)
+	TEST_ASSERT(collar in corgi, "Collar not placed on corgi")
+	TEST_ASSERT_EQUAL(corgi.name, "corgi", "animal name not preserved")
+
+	qdel(collar)
+	qdel(corgi)
+
+	corgi = player.spawn_mob_nearby(/mob/living/simple_animal/pet/dog/corgi)
+	chair.buckle_mob(corgi) // So it doesn't wander off
+
+	collar = player.spawn_obj_in_hand(/obj/item/petcollar)
+	collar.tagname = "Bucephalus"
+	player.click_on(corgi)
+	TEST_ASSERT(collar in corgi, "Collar not placed on corgi")
+	TEST_ASSERT_EQUAL(corgi.name, "Bucephalus", "animal name not changed")
+