[MIRROR] Refactor /turf/var/intact [MDB IGNORE] (#9114)

* Refactor /turf/var/intact (#62331)

Turfs have a variable, intact, which conflates three meanings:

    Determining whether there's something that can be pried out, such as directly with a crowbar or indirectly with a tile stack and a crowbar off-hand.
    Determining whether underfloor pieces are visible.
    Determining whether underfloor pieces can be interacted with - by players with tools, through interaction with effects like chemical acid, or foam.

When plating is hit with a stack of tiles, /turf/open/floor/attackby checks whether the turf is intact, and if so, ends the attack chain regardless of whether or not the attempt to hotswap a turf (with a crowbar) is successful or not. However, turfs which want the underfloor to be visible - such as catwalks and glass - set the intact variable to FALSE, and so can be repeatedly placed over one another, as if they were the first tile to be placed over the plating.

This refactors /turf/var/intact into two distinct variables:

    /turf/var/overfloor_placed, for whether or not there is something over plating.
    /turf/var/underfloor_visible, for whether or not the various underfloor pieces should be invisible, visible, or both visible and interactable.

All references to /turf/var/intact have been replaced with an equivalent overfloor_placed or underfloor_visible reference, depending on which check is appropriate. underfloor_accessibility can take one of UNDERFLOOR_HIDDEN, UNDERFLOOR_VISIBLE, or UNDERFLOOR_INTERACTABLE. This prevents cases such as acid foam or tools phasing through glass floors to affect the underfloor pieces underneath, and covers all kinds of unusual, not-wiring-visiblity usage such as Holodeck completeness, Revenant interaction, or station integrity checking.

* Refactor /turf/var/intact

* Thank

Co-authored-by: esainane <esainane+github@gmail.com>
Co-authored-by: Funce <funce.973@gmail.com>

code/game/objects/effects/anomalies.dm

@@ -142,7 +142,7 @@
 		if(!O.anchored)
 			if(isturf(O.loc))
 				var/turf/T = O.loc
-				if(T.intact && HAS_TRAIT(O, TRAIT_T_RAY_VISIBLE))
+				if(T.underfloor_accessibility < UNDERFLOOR_INTERACTABLE && HAS_TRAIT(O, TRAIT_T_RAY_VISIBLE))
 					continue
 			var/mob/living/target = locate() in view(4,src)
 			if(target && !target.stat)

code/game/objects/effects/effect_system/effects_foam.dm

@@ -144,7 +144,7 @@
 			continue
 		if(isturf(O.loc))
 			var/turf/T = O.loc
-			if(T.intact && HAS_TRAIT(O, TRAIT_T_RAY_VISIBLE))
+			if(T.underfloor_accessibility < UNDERFLOOR_INTERACTABLE && HAS_TRAIT(O, TRAIT_T_RAY_VISIBLE))
 				continue
 		if(lifetime % reagent_divisor)
 			reagents.expose(O, VAPOR, fraction)

code/game/objects/effects/effect_system/effects_smoke.dm

@@ -241,7 +241,7 @@
 		for(var/atom/movable/AM in T)
 			if(AM.type == src.type)
 				continue
-			if(T.intact && HAS_TRAIT(AM, TRAIT_T_RAY_VISIBLE))
+			if(T.underfloor_accessibility < UNDERFLOOR_INTERACTABLE && HAS_TRAIT(AM, TRAIT_T_RAY_VISIBLE))
 				continue
 			reagents.expose(AM, TOUCH, fraction)
 

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

@@ -78,7 +78,7 @@
 	if(I.tool_behaviour == TOOL_WRENCH)
 		if(mode == DISCONNECTED)
 			var/turf/T = loc
-			if(isturf(T) && !T.intact)
+			if(isturf(T) && T.underfloor_accessibility >= UNDERFLOOR_INTERACTABLE)
 				attached = locate() in T
 				if(!attached)
 					to_chat(user, span_warning("\The [src] must be placed over an exposed, powered cable node!"))

code/game/objects/obj_defense.dm

@@ -45,7 +45,7 @@
 		return
 	if(isturf(loc))
 		var/turf/T = loc
-		if(T.intact && HAS_TRAIT(src, TRAIT_T_RAY_VISIBLE))
+		if(T.underfloor_accessibility < UNDERFLOOR_INTERACTABLE && HAS_TRAIT(src, TRAIT_T_RAY_VISIBLE))
 			return
 	take_damage(400, BRUTE, MELEE, 0, get_dir(src, B))
 
@@ -128,7 +128,7 @@ GLOBAL_DATUM_INIT(acid_overlay, /mutable_appearance, mutable_appearance('icons/e
 /obj/fire_act(exposed_temperature, exposed_volume)
 	if(isturf(loc))
 		var/turf/T = loc
-		if(T.intact && HAS_TRAIT(src, TRAIT_T_RAY_VISIBLE))
+		if(T.underfloor_accessibility < UNDERFLOOR_INTERACTABLE && HAS_TRAIT(src, TRAIT_T_RAY_VISIBLE))
 			return
 	if(exposed_temperature && !(resistance_flags & FIRE_PROOF))
 		take_damage(clamp(0.02 * exposed_temperature, 0, 20), BURN, FIRE, 0)