QoL tweaks to stackable item component

code/modules/mob/living/carbon/human/human_update_icons.dm

@@ -662,21 +662,14 @@ generate/load female uniform sprites matching all previously decided variables
 	use_height_offset = TRUE,
 )
 
+	// NON-MODULE CHANGE // UPSTREAM ME
 	//Find a valid icon_state from variables+arguments
-	var/t_state
-	if(override_state)
-		t_state = override_state
-	else
-		t_state = !isinhands ? (worn_icon_state ? worn_icon_state : icon_state) : (inhand_icon_state ? inhand_icon_state : icon_state)
-
+	var/t_state = override_state || (isinhands ? inhand_icon_state : worn_icon_state) || icon_state
 	//Find a valid icon file from variables+arguments
-	var/file2use
-	if(override_file)
-		file2use = override_file
-	else
-		file2use = !isinhands ? (worn_icon ? worn_icon : default_icon_file) : default_icon_file
+	var/file2use = override_file || (isinhands ? null : worn_icon) || default_icon_file
 	//Find a valid layer from variables+arguments
-	var/layer2use = alternate_worn_layer ? alternate_worn_layer : default_layer
+	var/layer2use = alternate_worn_layer || default_layer
+	// NON-MODULE CHANGE END
 
 	var/mutable_appearance/standing
 	if(female_uniform)
@@ -687,7 +680,7 @@ generate/load female uniform sprites matching all previously decided variables
 	//Get the overlays for this item when it's being worn
 	//eg: ammo counters, primed grenade flashes, etc.
 	var/list/worn_overlays = worn_overlays(standing, isinhands, file2use)
-	if(worn_overlays?.len)
+	if(length(worn_overlays)) // NON-MODULE CHANGE
 		if(!isinhands && default_layer && ishuman(loc) && use_height_offset)
 			var/mob/living/carbon/human/human_loc = loc
 			if(human_loc.get_mob_height() != HUMAN_HEIGHT_MEDIUM)

maplestation_modules/code/__DEFINES/signals.dm

@@ -3,9 +3,6 @@
 /// (Flavor text should stay at the very very bottom though)
 #define COMSIG_LIVING_LATE_EXAMINE "late_examine"
 
-/// Item generating their worn icon
-#define COMSIG_ITEM_WORN_ICON_MADE "item_worn_icon_made"
-
 /// Entering or exiting a vent.
 #define COMSIG_HANDLE_VENTCRAWLING "handle_ventcrawl"
 	/// Return to block entrance / exit

maplestation_modules/code/datums/components/stackable_item.dm

@@ -1,15 +1,3 @@
-/obj/item/build_worn_icon(
-	default_layer = 0,
-	default_icon_file = null,
-	isinhands = FALSE,
-	female_uniform = NO_FEMALE_UNIFORM,
-	override_state = null,
-	override_file = null,
-	use_height_offset = TRUE,
-)
-	. = ..()
-	SEND_SIGNAL(src, COMSIG_ITEM_WORN_ICON_MADE, ., default_layer, default_icon_file, isinhands, female_uniform, override_state, override_file)
-
 /**
  * Stackble item component
  *
@@ -18,6 +6,8 @@
  * When the parent is equipped, so is the attached item. And when the parent is dropped, so is the attached item.
  */
 /datum/component/stackable_item
+	/// Descriptor for what you can attach to this item.
+	var/wearable_descriptor = ""
 	/// List of types that can be worn.
 	/// Swap to a typecache if people make really large lists.
 	var/list/wearables
@@ -30,31 +20,34 @@
 	/// Optional callback that is called when an item is dropped.
 	var/datum/callback/on_drop
 
-/datum/component/stackable_item/Initialize(list/wearables, datum/callback/can_stack, datum/callback/on_equip, datum/callback/on_drop)
+/datum/component/stackable_item/Initialize(list/wearables, wearable_descriptor, datum/callback/can_stack, datum/callback/on_equip, datum/callback/on_drop)
 	if(!isitem(parent))
 		return COMPONENT_INCOMPATIBLE
 
 	src.wearables = wearables
+	src.wearable_descriptor = wearable_descriptor
 	src.can_stack = can_stack
 	src.on_equip = on_equip
 	src.on_drop = on_drop
 
 /datum/component/stackable_item/RegisterWithParent()
-	RegisterSignal(parent, COMSIG_ITEM_WORN_ICON_MADE, PROC_REF(update_worn_icon))
+	RegisterSignal(parent, COMSIG_ATOM_ATTACKBY, PROC_REF(item_attackby))
+	RegisterSignal(parent, COMSIG_ATOM_EXAMINE, PROC_REF(on_examine))
 	RegisterSignal(parent, COMSIG_ATOM_EXITED, PROC_REF(atom_exited))
-	RegisterSignal(parent, COMSIG_ITEM_EQUIPPED, PROC_REF(item_equipped))
 	RegisterSignal(parent, COMSIG_ITEM_DROPPED, PROC_REF(item_dropped))
-	RegisterSignal(parent, COMSIG_ATOM_ATTACKBY, PROC_REF(item_attackby))
+	RegisterSignal(parent, COMSIG_ITEM_EQUIPPED, PROC_REF(item_equipped))
+	RegisterSignal(parent, COMSIG_ITEM_GET_WORN_OVERLAYS, PROC_REF(update_worn_icon))
 	RegisterSignals(parent, list(COMSIG_ATOM_DESTRUCTION, COMSIG_OBJ_DECONSTRUCT), PROC_REF(on_deconstruct))
 
 /datum/component/stackable_item/UnregisterFromParent()
 	UnregisterSignal(parent, list(
-		COMSIG_ITEM_WORN_ICON_MADE,
-		COMSIG_ATOM_EXITED,
-		COMSIG_ITEM_EQUIPPED,
-		COMSIG_ITEM_DROPPED,
 		COMSIG_ATOM_ATTACKBY,
 		COMSIG_ATOM_DESTRUCTION,
+		COMSIG_ATOM_EXAMINE,
+		COMSIG_ATOM_EXITED,
+		COMSIG_ITEM_DROPPED,
+		COMSIG_ITEM_EQUIPPED,
+		COMSIG_ITEM_GET_WORN_OVERLAYS,
 		COMSIG_OBJ_DECONSTRUCT,
 	))
 
@@ -65,32 +58,24 @@
 	on_drop = null
 	return ..()
 
-/datum/component/stackable_item/proc/update_worn_icon(
-	obj/item/source,
-	mutable_appearance/created_icon,
-	default_layer,
-	default_icon_file,
-	isinhands,
-	female_uniform,
-	override_state,
-	override_file,
-)
+/datum/component/stackable_item/proc/on_examine(obj/item/source, mob/user, list/examine_list)
+	SIGNAL_HANDLER
+
+	if(isnull(stacked_on))
+		if(wearable_descriptor)
+			examine_list += span_notice("Looks like you could attach [wearable_descriptor] to it.")
+
+	else
+		examine_list += span_notice("It has \a [stacked_on] attached.")
+
+/datum/component/stackable_item/proc/update_worn_icon(obj/item/source, list/overlays, mutable_appearance/standing, isinhands, ...)
 	SIGNAL_HANDLER
 
 	if(isinhands || isnull(stacked_on))
 		return
 
-	var/mutable_appearance/stacked_overlay = stacked_on.build_worn_icon(
-		default_layer,
-		default_icon_file,
-		isinhands,
-		female_uniform,
-		override_state,
-		override_file,
-	)
-
 	// Add in our new worn icon as an overlay of our item's icon.
-	created_icon.overlays.Add(stacked_overlay)
+	overlays += stacked_on.build_worn_icon(standing.layer)
 
 /datum/component/stackable_item/proc/atom_exited(obj/item/source, atom/movable/gone, direction)
 	SIGNAL_HANDLER

maplestation_modules/code/modules/clothing/glasses/hud_eyepatches.dm

@@ -8,22 +8,21 @@
 	. = ..()
 	AddComponent(/datum/component/stackable_item, \
 		wearables = list(/obj/item/clothing/glasses/hud), \
+		wearable_descriptor = "a HUD", \
 		can_stack = CALLBACK(src, PROC_REF(can_attach_hud)), \
 		on_drop = CALLBACK(src, PROC_REF(on_drop_patch)), \
 	)
 
 /obj/item/clothing/glasses/eyepatch/proc/can_attach_hud(obj/item/source, obj/item/clothing/glasses/hud/incoming_hud, mob/user)
 	// Basically, stops you from attaching HUDglasses. We only want the ones with one eye covered.
-	return (incoming_hud.flash_protect == 0 && incoming_hud.tint == 0)
+	return !(incoming_hud.flags_cover & GLASSESCOVERSEYES)
 
 /obj/item/clothing/glasses/eyepatch/proc/on_drop_patch(obj/item/clothing/glasses/hud/equipped_hud, mob/living/carbon/user, silent)
-	if(!istype(user))
+	if(!equipped_hud.hud_type)
 		return
-	if(user.glasses != src)
-		return
-	// This is HUGE hack but hud glasses rely on the user.glasses var to be set to the hud glasses
-	// If this ever changes this must be removed because then it will call dropped twice, which isn't bad but can be weird
-	var/obj/item/pre_slot = user.glasses
-	user.glasses = equipped_hud
-	equipped_hud.dropped(user, silent)
-	user.glasses = pre_slot
+
+	// A bit of a hack but HUD code checks that user.glasses == equipped_hud
+	// Which it is not here
+	// So even though equipping the hud works fine, unequipping it will fail
+	var/datum/atom_hud/our_hud = GLOB.huds[equipped_hud.hud_type]
+	our_hud.hide_from(user)