Adds a strict limit for how many antagonists of a type can be added i…

…n the round via storyteller (Bubberstation#1834)

## About The Pull Request

Adds a strict limit for how many antagonists of the same type can be
added in the round. This affects both midrounds and roundstarts.

### Current limits are:
- Bloodsucker: 3
- Changeling: 4
- Heretic: 2
- Malfunctioning AI: 1
- Nuke Ops: 5
- Spies: 4
- Traitor: 6

If an antagonist type is not listed here, there is no limit.

This does not affect an admin's ability to bus in additional antagonists
via the antag panel. This just affects storyteller.

## Why It's Good For The Game

Storyteller does not actually have a maximum cap of how many antagonists
of a certain type can be in the game. This means that while the maximum
heretics that storyteller can spawn roundstart is 2, there is actually
no limit (except for cost) for how many heretics can be in a round, as
the midround heretic event does not consider existing heretics in the
round.

This PR fixes that and adds a hard cap to antagonists of a certain type
in a round. This should prevent the rare and extremely stressful round
of 6 heretics spawning or something insane.

## Proof Of Testing

Untested. Can't really test this because I can't fake antag players.

## Changelog


:cl: BurgerBB
balance: Adds a strict limit for how many antagonists of the same type
can be added in the round. This affects both midrounds and roundstarts.
/:cl:

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modular_zubbers/code/modules/storyteller/event_defines/roleset/_antagonist_event.dm

@@ -38,6 +38,8 @@
 	var/base_antags = 2
 	/// How many maximum antags can we spawn
 	var/maximum_antags = 6
+	/// Strict limit on how many antagonists of this type that should be in this round. 0 to ignore.
+	var/maximum_antags_global = 0
 	/// For this many players we'll add 1 up to the maximum antag amount
 	var/denominator = 20
 	/// The antag flag to be used
@@ -83,8 +85,22 @@
 	typepath = /datum/round_event/antagonist/solo
 
 /datum/round_event_control/antagonist/proc/get_antag_amount()
+
 	var/people = SSgamemode.get_correct_popcount()
 	var/amount = base_antags + FLOOR(people / denominator, 1)
+
+	if(antag_datum && maximum_antags_global > 0)
+		var/antag_slots_left = maximum_antags_global
+		for(var/datum/antagonist/existing_antagonist as anything in GLOB.antagonists)
+			if(QDELETED(existing_antagonist) || QDELETED(existing_antagonist.owner) || QDELETED(existing_antagonist.owner.current)) //This feels messy, but it just werks.
+				continue
+			if(!istype(existing_antagonist,antag_datum)) //Obviously ignore other antagonists.
+				continue
+			antag_slots_left-- //Slot is occupied.
+			if(antag_slots_left <= 0) //No point in checking anymore.
+				break
+		amount = min(amount,antag_slots_left)
+
 	return min(amount, maximum_antags)
 
 /datum/round_event/antagonist

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/bloodsucker.dm

@@ -9,6 +9,7 @@
 
 	base_antags = 2
 	maximum_antags = 3
+	maximum_antags_global = 3
 
 	tags = list(TAG_COMBAT, TAG_SPOOKY, TAG_CREW_ANTAG)
 

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/changeling.dm

@@ -6,6 +6,7 @@
 	antag_datum = /datum/antagonist/changeling
 	weight = 8
 	min_players = 20
+	maximum_antags_global = 4
 
 	tags = list(TAG_COMBAT, TAG_CREW_ANTAG)
 

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/heretic.dm

@@ -7,8 +7,9 @@
 	weight = 8
 	min_players = 30
 
-	base_antags = 2
-	maximum_antags = 3
+	base_antags = 1
+	maximum_antags = 2
+	maximum_antags_global = 2
 
 	tags = list(TAG_COMBAT, TAG_SPOOKY, TAG_CREW_ANTAG)
 

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/malf.dm

@@ -4,6 +4,7 @@
 
 	base_antags = 1
 	maximum_antags = 1
+	maximum_antags_global = 1
 
 	min_players = 20
 

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/nuke_ops.dm

@@ -11,6 +11,7 @@
 
 	base_antags = 2
 	maximum_antags = 5
+	maximum_antags_global = 5
 
 	typepath = /datum/round_event/antagonist/team/nukie
 

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/spies.dm

@@ -5,6 +5,7 @@
 	antag_flag = ROLE_SPY
 	antag_datum = /datum/antagonist/spy
 	weight = 8
+	maximum_antags_global = 4
 
 	tags = list(TAG_CREW_ANTAG)
 

modular_zubbers/code/modules/storyteller/event_defines/roleset/crew_antagonists/traitor.dm

@@ -5,6 +5,7 @@
 	antag_flag = ROLE_TRAITOR
 	antag_datum = /datum/antagonist/traitor
 	weight = 8
+	maximum_antags_global = 6
 
 	tags = list(TAG_CREW_ANTAG)