[MIRROR] (code bounty) refactors all uses of Crossed() and Uncrossed() into signals sent to loc, tracked by connect_loc (#5524)

* (code bounty) refactors all uses of Crossed() and Uncrossed() into signals sent to loc, tracked by connect_loc

* WHEW THAT WAS EASY

* Update ammo.dm

Co-authored-by: Kylerace <kylerlumpkin1@gmail.com>
Co-authored-by: Gandalf <jzo123@hotmail.com>

code/modules/assembly/bomb.dm

@@ -80,13 +80,6 @@
 	else
 		bombtank.release()
 
-//Assembly / attached device memes
-
-/obj/item/onetankbomb/Crossed(atom/movable/AM as mob|obj) //for mousetraps
-	. = ..()
-	if(bombassembly)
-		bombassembly.Crossed(AM)
-
 /obj/item/onetankbomb/on_found(mob/finder) //for mousetraps
 	if(bombassembly)
 		bombassembly.on_found(finder)

code/modules/assembly/holder.dm

@@ -43,6 +43,7 @@
 	else
 		a_right = A
 	A.holder_movement()
+	A.on_attach()
 
 /obj/item/assembly_holder/update_appearance(updates=ALL)
 	. = ..()
@@ -70,13 +71,6 @@
 		right.add_overlay("[right_overlay]_l")
 	. += right
 
-/obj/item/assembly_holder/Crossed(atom/movable/AM as mob|obj)
-	. = ..()
-	if(a_left)
-		a_left.Crossed(AM)
-	if(a_right)
-		a_right.Crossed(AM)
-
 /obj/item/assembly_holder/on_found(mob/finder)
 	if(a_left)
 		a_left.on_found(finder)

code/modules/assembly/infrared.dm

@@ -229,12 +229,19 @@
 	pass_flags_self = LETPASSTHROW
 	var/obj/item/assembly/infra/master
 
-/obj/effect/beam/i_beam/Crossed(atom/movable/AM as mob|obj)
+/obj/effect/beam/i_beam/Initialize(mapload)
 	. = ..()
+	var/static/list/loc_connections = list(
+		COMSIG_ATOM_ENTERED = .proc/on_entered,
+	)
+	AddElement(/datum/element/connect_loc, src, loc_connections)
+
+/obj/effect/beam/i_beam/proc/on_entered(datum/source, atom/movable/AM as mob|obj)
+	SIGNAL_HANDLER
 	if(istype(AM, /obj/effect/beam))
 		return
 	if (isitem(AM))
 		var/obj/item/I = AM
 		if (I.item_flags & ABSTRACT)
 			return
-	master.trigger_beam(AM, get_turf(src))
+	INVOKE_ASYNC(master, /obj/item/assembly/infra.proc/trigger_beam, AM, get_turf(src))

code/modules/assembly/mousetrap.dm

@@ -9,6 +9,17 @@
 	drop_sound = 'sound/items/handling/component_drop.ogg'
 	pickup_sound =  'sound/items/handling/component_pickup.ogg'
 
+	///if we are attached to an assembly holder, we attach a connect_loc element to ourselves that listens to this from the holder
+	var/static/list/holder_connections = list(
+		COMSIG_ATOM_ENTERED = .proc/on_entered,
+	)
+
+/obj/item/assembly/mousetrap/Initialize()
+	. = ..()
+	var/static/list/loc_connections = list(
+		COMSIG_ATOM_ENTERED = .proc/on_entered,
+	)
+	AddElement(/datum/element/connect_loc, src, loc_connections)
 
 /obj/item/assembly/mousetrap/examine(mob/user)
 	. = ..()
@@ -34,6 +45,14 @@
 	. = ..()
 	holder?.update_icon(updates)
 
+/obj/item/assembly/mousetrap/on_attach()
+	. = ..()
+	AddElement(/datum/element/connect_loc, holder, holder_connections)
+
+/obj/item/assembly/mousetrap/on_detach()
+	. = ..()
+	RemoveElement(/datum/element/connect_loc, holder, holder_connections)
+
 /obj/item/assembly/mousetrap/proc/triggered(mob/target, type = "feet")
 	if(!armed)
 		return
@@ -107,7 +126,8 @@
 	return ..()
 
 
-/obj/item/assembly/mousetrap/Crossed(atom/movable/AM as mob|obj)
+/obj/item/assembly/mousetrap/proc/on_entered(datum/source, atom/movable/AM as mob|obj)
+	SIGNAL_HANDLER
 	if(armed)
 		if(ismob(AM))
 			var/mob/MM = AM
@@ -115,15 +135,13 @@
 				if(ishuman(AM))
 					var/mob/living/carbon/H = AM
 					if(H.m_intent == MOVE_INTENT_RUN)
-						triggered(H)
+						INVOKE_ASYNC(src, .proc/triggered, H)
 						H.visible_message("<span class='warning'>[H] accidentally steps on [src].</span>", \
 							"<span class='warning'>You accidentally step on [src]</span>")
 				else if(ismouse(MM) || israt(MM) || isregalrat(MM))
-					triggered(MM)
+					INVOKE_ASYNC(src, .proc/triggered, MM)
 		else if(AM.density) // For mousetrap grenades, set off by anything heavy
-			triggered(AM)
-	..()
-
+			INVOKE_ASYNC(src, .proc/triggered, AM)
 
 /obj/item/assembly/mousetrap/on_found(mob/finder)
 	if(armed)