From dac07b526461c554bcf54b835d4a7e89c6b5fec6 Mon Sep 17 00:00:00 2001
From: Ghom <42542238+Ghommie@users.noreply.github.com>
Date: Sun, 14 Nov 2021 11:42:39 +0100
Subject: [PATCH] Fixes Multi lavaland tumor combat (and possible sources of
 harddels) (#62540)

This will fix #62065 by adding a new trait that prevents mobs from activating another elite tumor structure until he's won or lost the previous challenge, along with possible sources of harddels by making sure the hard-refs are properly cleared if the mobs get qdeleted.
---
 code/__DEFINES/traits.dm                      |  2 +
 .../hostile/mining_mobs/elites/elite.dm       | 82 ++++++++++++-------
 2 files changed, 55 insertions(+), 29 deletions(-)

diff --git a/code/__DEFINES/traits.dm b/code/__DEFINES/traits.dm
index dbe7517a110..7410d78ce83 100644
--- a/code/__DEFINES/traits.dm
+++ b/code/__DEFINES/traits.dm
@@ -327,6 +327,8 @@ Remember to update _globalvars/traits.dm if you're adding/removing/renaming trai
 #define TRAIT_ALLOWED_HONORBOUND_ATTACK "allowed_honorbound_attack"
 /// The user is sparring
 #define TRAIT_SPARRING "sparring"
+/// The user is currently challenging an elite mining mob. Prevents him from challenging another until he's either lost or won.
+#define TRAIT_ELITE_CHALLENGER "elite_challenger"
 
 #define TRAIT_NOBLEED "nobleed" //This carbon doesn't bleed
 /// This atom can ignore the "is on a turf" check for simple AI datum attacks, allowing them to attack from bags or lockers as long as any other conditions are met
diff --git a/code/modules/mob/living/simple_animal/hostile/mining_mobs/elites/elite.dm b/code/modules/mob/living/simple_animal/hostile/mining_mobs/elites/elite.dm
index 09e999290e9..580cb98e2d9 100644
--- a/code/modules/mob/living/simple_animal/hostile/mining_mobs/elites/elite.dm
+++ b/code/modules/mob/living/simple_animal/hostile/mining_mobs/elites/elite.dm
@@ -126,7 +126,7 @@ While using this makes the system rely on OnFire, it still gives options for tim
 	var/activity = TUMOR_INACTIVE
 	var/boosted = FALSE
 	var/times_won = 0
-	var/mob/living/carbon/human/activator = null
+	var/mob/living/carbon/human/activator
 	var/mob/living/simple_animal/hostile/asteroid/elite/mychild = null
 	var/potentialspawns = list(/mob/living/simple_animal/hostile/asteroid/elite/broodmother,
 								/mob/living/simple_animal/hostile/asteroid/elite/pandora,
@@ -138,19 +138,29 @@ While using this makes the system rely on OnFire, it still gives options for tim
 	if(ishuman(user))
 		switch(activity)
 			if(TUMOR_PASSIVE)
+				// Prevents the user from being forcemoved back and forth between two elite arenas.
+				if(HAS_TRAIT(user, TRAIT_ELITE_CHALLENGER))
+					user.visible_message(span_warning("[user] reaches for [src] with [user.p_their()] arm, but nothing happens."),
+						span_warning("You reach for [src] with your arm... but nothing happens."))
+					return
 				activity = TUMOR_ACTIVE
-				visible_message(span_boldwarning("[src] convulses as your arm enters its radius.  Your instincts tell you to step back."))
-				activator = user
+				user.visible_message(span_boldwarning("[src] convulses as [user]'s arm enters its radius.  Uh-oh..."),
+					span_boldwarning("[src] convulses as your arm enters its radius.  Your instincts tell you to step back."))
+				make_activator(user)
 				if(boosted)
 					mychild.playsound_local(get_turf(mychild), 'sound/effects/magic.ogg', 40, 0)
 					to_chat(mychild, "<b>Someone has activated your tumor.  You will be returned to fight shortly, get ready!</b>")
 				addtimer(CALLBACK(src, .proc/return_elite), 30)
 				INVOKE_ASYNC(src, .proc/arena_checks)
 			if(TUMOR_INACTIVE)
+				if(HAS_TRAIT(user, TRAIT_ELITE_CHALLENGER))
+					user.visible_message(span_warning("[user] reaches for [src] with [user.p_their()] arm, but nothing happens."),
+						span_warning("You reach for [src] with your arm... but nothing happens."))
+					return
 				activity = TUMOR_ACTIVE
 				var/mob/dead/observer/elitemind = null
 				visible_message(span_boldwarning("[src] begins to convulse.  Your instincts tell you to step back."))
-				activator = user
+				make_activator(user)
 				if(!boosted)
 					addtimer(CALLBACK(src, .proc/spawn_elite), 30)
 					return
@@ -165,7 +175,7 @@ While using this makes the system rely on OnFire, it still gives options for tim
 				else
 					visible_message(span_boldwarning("The stirring stops, and nothing emerges.  Perhaps try again later."))
 					activity = TUMOR_INACTIVE
-					activator = null
+					clear_activator(user)
 
 /obj/structure/elite_tumor/proc/spawn_elite(mob/dead/observer/elitemind)
 	var/selectedspawn = pick(potentialspawns)
@@ -177,8 +187,12 @@ While using this makes the system rely on OnFire, it still gives options for tim
 		mychild.sentience_act()
 		notify_ghosts("\A [mychild] has been awakened in \the [get_area(src)]!", source = mychild, action = NOTIFY_ORBIT, flashwindow = FALSE, header = "Lavaland Elite awakened")
 	icon_state = "tumor_popped"
+	RegisterSignal(mychild, COMSIG_PARENT_QDELETING, .proc/mychild_gone_missing)
 	INVOKE_ASYNC(src, .proc/arena_checks)
 
+/obj/structure/elite_tumor/proc/mychild_gone_missing()
+	mychild = null
+
 /obj/structure/elite_tumor/proc/return_elite()
 	mychild.forceMove(loc)
 	visible_message(span_boldwarning("[mychild] emerges from [src]!"))
@@ -197,9 +211,23 @@ While using this makes the system rely on OnFire, it still gives options for tim
 /obj/structure/elite_tumor/Destroy()
 	STOP_PROCESSING(SSobj, src)
 	mychild = null
-	activator = null
+	clear_activator(activator)
 	return ..()
 
+/obj/structure/elite_tumor/proc/make_activator(mob/user)
+	if(activator)
+		return
+	activator = user
+	ADD_TRAIT(user, TRAIT_ELITE_CHALLENGER, REF(src))
+	RegisterSignal(user, COMSIG_PARENT_QDELETING, .proc/clear_activator)
+
+/obj/structure/elite_tumor/proc/clear_activator(mob/source)
+	if(!activator)
+		return
+	activator = null
+	REMOVE_TRAIT(source, TRAIT_ELITE_CHALLENGER, REF(src))
+	UnregisterSignal(source, COMSIG_PARENT_QDELETING)
+
 /obj/structure/elite_tumor/process(delta_time)
 	if(isturf(loc))
 		for(var/mob/living/simple_animal/hostile/asteroid/elite/elitehere in loc)
@@ -230,21 +258,26 @@ While using this makes the system rely on OnFire, it still gives options for tim
 		addtimer(CALLBACK(src, .proc/arena_checks), 50)
 
 /obj/structure/elite_tumor/proc/fighters_check()
-	if(activator != null && activator.stat == DEAD || activity == TUMOR_ACTIVE && QDELETED(activator))
-		onEliteWon()
-	if(mychild != null && mychild.stat == DEAD || activity == TUMOR_ACTIVE && QDELETED(mychild))
+	if(QDELETED(mychild) || mychild.stat == DEAD)
 		onEliteLoss()
+		return
+	if(QDELETED(activator) || activator.stat == DEAD || (activator.health <= HEALTH_THRESHOLD_DEAD && HAS_TRAIT(activator, TRAIT_NODEATH)))
+		if(!QDELETED(activator) && HAS_TRAIT(activator, TRAIT_NODEATH)) // dust the unkillable activator
+			activator.dust(drop_items = TRUE)
+		onEliteWon()
 
 /obj/structure/elite_tumor/proc/arena_trap()
 	var/turf/T = get_turf(src)
 	if(loc == null)
 		return
+	var/datum/weakref/activator_ref = WEAKREF(activator)
+	var/datum/weakref/mychild_ref = WEAKREF(mychild)
 	for(var/t in RANGE_TURFS(12, T))
 		if(get_dist(t, T) == 12)
 			var/obj/effect/temp_visual/elite_tumor_wall/newwall
 			newwall = new /obj/effect/temp_visual/elite_tumor_wall(t, src)
-			newwall.activator = src.activator
-			newwall.ourelite = src.mychild
+			newwall.activator_ref = activator_ref
+			newwall.ourelite_ref = mychild_ref
 
 /obj/structure/elite_tumor/proc/border_check()
 	if(activator != null && get_dist(src, activator) >= 12)
@@ -261,23 +294,16 @@ While using this makes the system rely on OnFire, it still gives options for tim
 	visible_message(span_boldwarning("[src] begins to convulse violently before beginning to dissipate."))
 	visible_message(span_boldwarning("As [src] closes, something is forced up from down below."))
 	var/obj/structure/closet/crate/necropolis/tendril/lootbox = new /obj/structure/closet/crate/necropolis/tendril(loc)
-	if(!boosted)
-		mychild = null
-		activator = null
-		qdel(src)
-		return
-	var/lootpick = rand(1, 2)
-	if(lootpick == 1 && mychild.loot_drop != null)
-		new mychild.loot_drop(lootbox)
-	else
-		new /obj/item/tumor_shard(lootbox)
-	mychild = null
-	activator = null
+	if(boosted)
+		if(mychild.loot_drop != null && prob(50))
+			new mychild.loot_drop(lootbox)
+		else
+			new /obj/item/tumor_shard(lootbox)
 	qdel(src)
 
 /obj/structure/elite_tumor/proc/onEliteWon()
 	activity = TUMOR_PASSIVE
-	activator = null
+	clear_activator(activator)
 	mychild.revive(full_heal = TRUE, admin_revive = TRUE)
 	if(boosted)
 		times_won++
@@ -336,8 +362,8 @@ While using this makes the system rely on OnFire, it still gives options for tim
 	color = rgb(255,0,0)
 	light_range = MINIMUM_USEFUL_LIGHT_RANGE
 	light_color = COLOR_SOFT_RED
-	var/mob/living/carbon/human/activator = null
-	var/mob/living/simple_animal/hostile/asteroid/elite/ourelite = null
+	var/datum/weakref/activator_ref
+	var/datum/weakref/ourelite_ref
 
 /obj/effect/temp_visual/elite_tumor_wall/Initialize(mapload, new_caster)
 	. = ..()
@@ -348,11 +374,9 @@ While using this makes the system rely on OnFire, it still gives options for tim
 /obj/effect/temp_visual/elite_tumor_wall/Destroy()
 	if(smoothing_flags & (SMOOTH_CORNERS|SMOOTH_BITMASK))
 		QUEUE_SMOOTH_NEIGHBORS(src)
-	activator = null
-	ourelite = null
 	return ..()
 
 /obj/effect/temp_visual/elite_tumor_wall/CanAllowThrough(atom/movable/mover, border_dir)
 	. = ..()
-	if(mover == ourelite || mover == activator)
+	if(mover == ourelite_ref.resolve() || mover == activator_ref.resolve())
 		return FALSE