Allows roundstart observers to freely use antag HUD without losing respawnability (#23009)

* First pass

* do away with old antag hud variable

* rework cannotPossess

* some verification + cleanups

* Update code/modules/mob/dead/observer/observer_base.dm

Co-authored-by: Contrabang <91113370+Contrabang@users.noreply.github.com>

* splits up log call

* Slightly refactor proc calls, continuing contra's review

* Log admin

---------

Co-authored-by: Contrabang <91113370+Contrabang@users.noreply.github.com>

code/modules/mob/dead/observer/observer_base.dm

@@ -828,3 +828,17 @@ This is the proc mobs get to turn into a ghost. Forked from ghostize due to comp
 
 	var/datum/spawners_menu/menu = new /datum/spawners_menu(src)
 	menu.ui_interact(src)
+
+/**
+ * Check if a player has antag-hudded, and if so, if they can rejoin.
+ * Returns TRUE if the player can rejoin, and FALSE if the player is ineligible to rejoin.
+ * If allow_roundstart_observers is FALSE (TRUE by default), then any observers who were able to ahud due to joining roundstart will be excluded as well.
+ */
+/mob/dead/observer/proc/check_ahud_rejoin_eligibility(allow_roundstart_observers = TRUE)
+	if(!GLOB.configuration.general.restrict_antag_hud_rejoin || !has_ahudded())
+		return TRUE
+
+	if(is_roundstart_observer())
+		return allow_roundstart_observers
+	return FALSE
+

code/modules/mob/living/carbon/brain/robotic_brain.dm

@@ -62,7 +62,7 @@
 			to_chat(O, "<span class='boldnotice'>\A [src] has been activated. (<a href='?src=[O.UID()];jump=\ref[src]'>Teleport</a> | <a href='?src=[UID()];signup=\ref[O]'>Sign Up</a>)</span>")
 
 /obj/item/mmi/robotic_brain/proc/check_observer(mob/dead/observer/O)
-	if(cannotPossess(O))
+	if(!O.check_ahud_rejoin_eligibility())
 		return FALSE
 	if(jobban_isbanned(O, "Cyborg") || jobban_isbanned(O, "nonhumandept"))
 		return FALSE
@@ -121,6 +121,10 @@
 	to_chat(brainmob, "<b>Remember, the purpose of your existence is to serve [imprinted_master]'s every word, unless lawed  or placed into a mech in the future.</b>")
 	brainmob.mind.assigned_role = "Positronic Brain"
 
+	if(brainmob.has_ahudded())
+		log_admin("[key_name(brainmob)] has joined as a robot brain, after having toggled antag hud.")
+		message_admins("[key_name(brainmob)] has joined as a robot brain, after having toggled antag hud.")
+
 	visible_message("<span class='notice'>[src] chimes quietly.</span>")
 	become_occupied(occupied_icon)
 
@@ -155,7 +159,7 @@
 	if(!check_observer(O))
 		to_chat(O, "<span class='warning'>You cannot be \a [src].</span>")
 		return
-	if(cannotPossess(O))
+	if(!O.check_ahud_rejoin_eligibility())
 		to_chat(O, "<span class='warning'>Upon using the antagHUD you forfeited the ability to join the round.</span>")
 		return
 	if(jobban_isbanned(O, "Cyborg") || jobban_isbanned(O, "nonhumandept"))

code/modules/mob/living/silicon/pai/pai.dm

@@ -114,6 +114,10 @@
 	var/datum/data/pda/app/messenger/M = pda.find_program(/datum/data/pda/app/messenger)
 	M.toff = TRUE
 
+	if(has_ahudded())
+		message_admins("[key_name(src)] has joined as a pAI, having previously enabled antag hud.")
+		log_admin("[key_name(src)] has joined as a pAI, having previously enabled antag hud.")
+
 	// Software modules. No these var names have nothing to do with photoshop
 	for(var/PS in subtypesof(/datum/pai_software))
 		var/datum/pai_software/PSD = new PS(src)

code/modules/mob/living/silicon/pai/recruit.dm

@@ -355,7 +355,7 @@ GLOBAL_DATUM_INIT(paiController, /datum/paiController, new) // Global handler fo
 		return 0
 	if(!player_old_enough_antag(O.client,ROLE_PAI))
 		return 0
-	if(cannotPossess(O))
+	if(!O.check_ahud_rejoin_eligibility())
 		return 0
 	if(!HAS_TRAIT(O, TRAIT_RESPAWNABLE))
 		return 0

code/modules/mob/living/silicon/robot/drone/drone_manufacturer.dm

@@ -121,7 +121,7 @@
 	var/joinedasobserver = FALSE
 	if(isobserver(src))
 		var/mob/dead/observer/G = src
-		if(cannotPossess(G))
+		if(!G.check_ahud_rejoin_eligibility())
 			to_chat(usr, "<span class='warning'>Upon using the antagHUD you forfeited the ability to join the round.</span>")
 			return
 		if(G.started_as_observer == TRUE)

code/modules/mob/living/silicon/robot/drone/maint_drone.dm

@@ -291,7 +291,7 @@
 
 /mob/living/silicon/robot/drone/proc/request_player()
 	for(var/mob/dead/observer/O in GLOB.player_list)
-		if(cannotPossess(O))
+		if(!O.check_ahud_rejoin_eligibility())
 			continue
 		if(jobban_isbanned(O, "nonhumandept") || jobban_isbanned(O, "Drone"))
 			continue

code/modules/mob/living/simple_animal/hostile/terror_spiders/terror_ghost_interaction.dm

@@ -16,8 +16,10 @@
 	humanize_prompt += " Role: [spider_role_summary]"
 	if(user.ckey in GLOB.ts_ckey_blacklist)
 		error_on_humanize = "You are not able to control any terror spider this round."
-	else if(cannotPossess(user))
-		error_on_humanize = "You have enabled antag HUD and are unable to re-enter the round."
+	else if(isobserver(user))
+		var/mob/dead/observer/O = user
+		if(!O.check_ahud_rejoin_eligibility())
+			error_on_humanize = "You have enabled antag HUD and are unable to re-enter the round."
 	else if(!ai_playercontrol_allowtype)
 		error_on_humanize = "This specific type of terror spider is not player-controllable."
 	else if(degenerate)

code/modules/mob/mob_misc_procs.dm

@@ -137,13 +137,6 @@
 
 	return 1
 
-/proc/cannotPossess(A)
-	var/mob/dead/observer/G = A
-	if(G.has_enabled_antagHUD && GLOB.configuration.general.restrict_antag_hud_rejoin)
-		return 1
-	return 0
-
-
 /proc/iscuffed(A)
 	if(iscarbon(A))
 		var/mob/living/carbon/C = A
@@ -808,6 +801,12 @@ GLOBAL_LIST_INIT(intents, list(INTENT_HELP,INTENT_DISARM,INTENT_GRAB,INTENT_HARM
 /mob/proc/attempt_listen_to_deadsay()
 
 
+/mob/proc/is_roundstart_observer()
+	return (ckey in GLOB.roundstart_observer_keys)
+
+/mob/proc/has_ahudded()
+	return (ckey in GLOB.antag_hud_users)
+
 /// Proc to PROPERLY set mob invisibility, huds gotta get set too!
 /mob/proc/set_invisible(invis_value)
 	if(invis_value)

code/modules/mob/mob_vars.dm

@@ -122,8 +122,6 @@
 
 	var/move_on_shuttle = TRUE // Can move on the shuttle.
 
-	/// Whether antagHUD has been enabled previously.
-	var/has_enabled_antagHUD = FALSE
 	var/antagHUD = FALSE  // Whether AntagHUD is active right now
 	var/can_change_intents = TRUE //all mobs can change intents by default.
 	///Override for sound_environments. If this is set the user will always hear a specific type of reverb (Instead of the area defined reverb)

code/modules/mob/new_player/new_player.dm

@@ -186,8 +186,9 @@
 			src << browse(null, "window=playersetup")
 			spawning = TRUE
 			stop_sound_channel(CHANNEL_LOBBYMUSIC)
-
-
+			if(SSticker.current_state < GAME_STATE_PLAYING)
+				GLOB.roundstart_observer_keys |= ckey
+				to_chat(src, "<span class='notice'>As you observed before the round started, you can freely toggle antag-hud without losing respawnability.</span>")
 			observer.started_as_observer = 1
 			close_spawn_windows()
 			var/obj/O = locate("landmark*Observer-Start")