Unit tests, refactor & realignment for map loaded wall mounts (#93662)

## About The Pull Request
This 1st has to be PR'd so the integration tests can point out all
wallmounts that could not find a support structure to mount on. I then
will do many map edits to align them onto the closest atom

Yes we no longer use wall mount but atom mounted component. All objects
that are mounted on windows/tables & fences now also fall off when
destroyed

It'll probably be a WHILE before I can fix all wall mounts. Long day.
Expect me to misalign many stuff to fix failing CI so make sure to
provide suggestions when possible

Improved wallmount code overall
- Fixes #93793


## Changelog
🆑
fix: fixes all incorrectly maploded wall mounts that aren't actually
hanging on any support structure
fix: objects mounted on tables, windows & fences also fall off now when
destoryed
qol: lights can be mounted on windows
qol: cameras can be mounted on windows
qol: buttons can be mounted on tables
refactor: improved how wall mounts interact with objects as a whole
report bugs on github
/🆑

code/game/objects/items/apc_frame.dm

@@ -6,34 +6,21 @@
 	result_path = /obj/machinery/power/apc/auto_name
 
 /obj/item/wallframe/apc/try_build(turf/on_wall, user)
-	if(!..())
-		return
 	var/turf/T = get_turf(on_wall) //the user is not where it needs to be.
 	var/area/A = get_area(user)
 	if(A.apc)
 		to_chat(user, span_warning("This area already has an APC!"))
-		return //only one APC per area
-	if(!A.requires_power)
+		return FALSE //only one APC per area
+	if(!A.requires_power || A.always_unpowered)
 		to_chat(user, span_warning("You cannot place [src] in this area!"))
-		return //can't place apcs in areas with no power requirement
+		return FALSE //can't place apcs in areas with no power requirement
 	for(var/obj/machinery/power/terminal/E in T)
 		if(E.master)
 			to_chat(user, span_warning("There is another network terminal here!"))
-			return
-		else
-			new /obj/item/stack/cable_coil(T, 10)
-			to_chat(user, span_notice("You cut the cables and disassemble the unused power terminal."))
-			qdel(E)
-	return TRUE
+			return FALSE
+	return ..()
 
-/obj/item/wallframe/apc/screwdriver_act(mob/living/user, obj/item/tool)
-	//overriding the wallframe parent screwdriver act with this one which allows applying to existing apc frames.
-
-	var/turf/turf = get_step(get_turf(user), user.dir)
-	if(iswallturf(turf))
-		if(locate(/obj/machinery/power/apc) in get_turf(user))
-			var/obj/machinery/power/apc/mounted_apc = locate(/obj/machinery/power/apc) in get_turf(user)
-			mounted_apc.wallframe_act(user, src)
-			return ITEM_INTERACT_SUCCESS
-		turf.item_interaction(user, src)
-	return ITEM_INTERACT_SUCCESS
+/obj/item/wallframe/apc/after_attach(obj/machinery/power/apc/attached_to)
+	for(var/obj/machinery/power/terminal/E in attached_to.loc)
+		attached_to.make_terminal()
+		return

code/game/objects/items/devices/radio/intercom.dm

@@ -39,7 +39,7 @@
 		return
 	RegisterSignal(current_area, COMSIG_AREA_POWER_CHANGE, PROC_REF(AreaPowerCheck))
 	if(mapload)
-		find_and_hang_on_wall()
+		find_and_hang_on_atom()
 	GLOB.intercoms_list += src
 
 /obj/item/radio/intercom/Destroy()

code/game/objects/items/stacks/sheets/sheet_types.dm

@@ -142,7 +142,7 @@ GLOBAL_LIST_INIT(metal_recipes, list ( \
 	new/datum/stack_recipe("telescreen turbine frame", /obj/item/wallframe/telescreen/turbine, 7, crafting_flags = NONE, category = CAT_STRUCTURE), \
 	new/datum/stack_recipe("telescreen engine frame", /obj/item/wallframe/telescreen/engine, 7, crafting_flags = NONE, category = CAT_STRUCTURE), \
 	new/datum/stack_recipe("telescreen auxbase frame", /obj/item/wallframe/telescreen/auxbase, 7, crafting_flags = NONE, category = CAT_STRUCTURE), \
-	new/datum/stack_recipe("tram controller frame", /obj/item/wallframe/tram/controller, 20, crafting_flags = NONE, category = CAT_STRUCTURE), \
+	new/datum/stack_recipe("tram controller frame", /obj/item/wallframe/tram, 20, crafting_flags = NONE, category = CAT_STRUCTURE), \
 	new/datum/stack_recipe("tram display frame", /obj/item/wallframe/indicator_display, 7, crafting_flags = NONE, category = CAT_STRUCTURE), \
 	null, \
 	new/datum/stack_recipe("iron door", /obj/structure/mineral_door/iron, 20, time = 5 SECONDS, crafting_flags = CRAFT_CHECK_DENSITY | CRAFT_ONE_PER_TURF | CRAFT_ON_SOLID_GROUND | CRAFT_APPLIES_MATS, category = CAT_DOORS), \

code/game/objects/items/wall_mounted.dm

@@ -6,66 +6,93 @@
 	lefthand_file = 'icons/mob/inhands/equipment/medical_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/equipment/medical_righthand.dmi'
 	w_class = WEIGHT_CLASS_SMALL
+	///The final object to construct after mount
 	var/result_path
-	var/wall_external = FALSE // For frames that are external to the wall they are placed on, like light fixtures and cameras.
-	var/pixel_shift //The amount of pixels
+	/// For frames that are external to the wall they are placed on, like light fixtures and cameras.
+	var/wall_external = FALSE
+	//The amount of pixels to shift when mounted
+	var/pixel_shift
 
-/obj/item/wallframe/proc/try_build(turf/on_wall, mob/user)
-	if(get_dist(on_wall,user) > 1)
+/**
+ * Returns an structure to mount on from the atom passed
+ * for e.g if its not an closed turf then return an structure on the turf to mount on
+ * Arguments
+ * * atom/structure - the atom or something in this atom we are trying to mount on
+*/
+/obj/item/wallframe/proc/find_support_structure(atom/structure)
+	SHOULD_BE_PURE(TRUE)
+
+	return isclosedturf(structure) ? structure : null
+
+/obj/item/wallframe/interact_with_atom(atom/interacting_with, mob/living/user, list/modifiers)
+	var/atom/support_structure = find_support_structure(interacting_with)
+	if(isnull(support_structure))
+		return NONE
+	if(!try_build(support_structure, user))
+		return ITEM_INTERACT_FAILURE
+
+	playsound(loc, 'sound/machines/click.ogg', 75, TRUE)
+	user.visible_message(span_notice("[user.name] attaches [src] to the wall."),
+		span_notice("You attach [src] to the wall."),
+		span_hear("You hear clicking."))
+
+	var/floor_to_support = get_dir(user, support_structure)
+	var/obj/hanging_object = new result_path(get_turf(user))
+	hanging_object.setDir(floor_to_support)
+	if(pixel_shift)
+		switch(floor_to_support)
+			if(NORTH)
+				hanging_object.pixel_y = pixel_shift
+			if(SOUTH)
+				hanging_object.pixel_y = -pixel_shift
+			if(EAST)
+				hanging_object.pixel_x = pixel_shift
+			if(WEST)
+				hanging_object.pixel_x = -pixel_shift
+	if(!hanging_object.find_and_hang_on_atom())
+		to_chat(user, span_warning("[src] Could not find all to mount on!."))
+		return
+	after_attach(hanging_object)
+	qdel(src)
+
+	return ITEM_INTERACT_SUCCESS
+
+/**
+ * Check if we can build on this support structure
+ *
+ * Arguments
+ * * atom/support - the atom we are trying to mount on
+ * * mob/user - the player attempting to do the mount
+*/
+/obj/item/wallframe/proc/try_build(atom/support, mob/user)
+	if(get_dist(support, user) > 1)
 		balloon_alert(user, "you are too far!")
-		return
-	var/floor_to_wall = get_dir(user, on_wall)
-	if(!(floor_to_wall in GLOB.cardinals))
+		return FALSE
+	var/floor_to_support = get_dir(user, support)
+	if(!(floor_to_support in GLOB.cardinals))
 		balloon_alert(user, "stand in line with wall!")
-		return
+		return FALSE
 	var/turf/T = get_turf(user)
-	var/area/A = get_area(T)
 	if(!isfloorturf(T))
 		balloon_alert(user, "cannot place here!")
-		return
-	if(A.always_unpowered)
-		balloon_alert(user, "cannot place in this area!")
-		return
-	if(check_wall_item(T, floor_to_wall, wall_external))
+		return FALSE
+	if(check_wall_item(T, floor_to_support, wall_external))
 		balloon_alert(user, "already something here!")
-		return
+		return FALSE
 
 	return TRUE
 
-/obj/item/wallframe/proc/attach(turf/on_wall, mob/user)
-	if(result_path)
-		playsound(src.loc, 'sound/machines/click.ogg', 75, TRUE)
-		user.visible_message(span_notice("[user.name] attaches [src] to the wall."),
-			span_notice("You attach [src] to the wall."),
-			span_hear("You hear clicking."))
-		var/floor_to_wall = get_dir(user, on_wall)
-
-		var/obj/hanging_object = new result_path(get_turf(user))
-		hanging_object.setDir(floor_to_wall)
-		if(pixel_shift)
-			switch(floor_to_wall)
-				if(NORTH)
-					hanging_object.pixel_y = pixel_shift
-				if(SOUTH)
-					hanging_object.pixel_y = -pixel_shift
-				if(EAST)
-					hanging_object.pixel_x = pixel_shift
-				if(WEST)
-					hanging_object.pixel_x = -pixel_shift
-		hanging_object.find_and_hang_on_wall()
-		after_attach(hanging_object)
-
-	qdel(src)
-
+/**
+ * Stuff to do after wallframe attached to support atom
+ *
+ * Arguments
+ * * obj/attached_to - the object that has been created on the atom
+*/
 /obj/item/wallframe/proc/after_attach(obj/attached_to)
 	transfer_fingerprints_to(attached_to)
 
 /obj/item/wallframe/screwdriver_act(mob/living/user, obj/item/tool)
-	// For camera-building borgs
-	var/turf/wall_turf = get_step(get_turf(user), user.dir)
-	if(iswallturf(wall_turf))
-		wall_turf.item_interaction(user, src)
-	return ITEM_INTERACT_SUCCESS
+	return interact_with_atom(get_step(get_turf(user), user.dir), user)
 
 /obj/item/wallframe/wrench_act(mob/living/user, obj/item/tool)
 	var/metal_amt = round(custom_materials[GET_MATERIAL_REF(/datum/material/iron)]/SHEET_MATERIAL_AMOUNT) //Replace this shit later