add: Pref viewer & bitflag helpers

code/__DEFINES/dcs/signals.dm

@@ -456,8 +456,10 @@
 #define COMSIG_MOB_THROW "mob_throw"
 ///called when a user is getting new weapon and we want to remove previous weapon to clear hands
 #define COMSIG_MOB_WEAPON_APPEARS "mob_weapon_appears"
-///from base of /mob/verb/examinate(): (atom/target)
-#define COMSIG_MOB_EXAMINATE "mob_examinate"
+/// from base of /mob/verb/examinate(): (atom/target)
+#define COMSIG_MOB_VERB_EXAMINATE "mob_examinate"
+/// from base of /mob/proc/run_examinate(): (atom/target, list/result)
+#define COMSIG_MOB_RUN_EXAMINATE "mob_run_examinate"
 ///from base of /mob/update_sight(): ()
 #define COMSIG_MOB_UPDATE_SIGHT "mob_update_sight"
 ////from /mob/living/say(): ()

code/__HELPERS/bitflags.dm

@@ -0,0 +1,7 @@
+#define HASBIT(CONTAINER, FLAG)     ((CONTAINER) & (FLAG))
+
+#define SETBIT(CONTAINER, FLAG)     (CONTAINER |= (FLAG))
+
+#define CLEARBIT(CONTAINER, FLAG)   (CONTAINER &= ~(FLAG))
+
+#define TOGGLEBIT(CONTAINER, FLAG)  (CONTAINER ^= (FLAG))

code/datums/components/pref_viewer.dm

@@ -0,0 +1,41 @@
+/datum/component/pref_viewer
+    var/list/preferences_to_show
+
+/datum/component/pref_viewer/Destroy(force)
+    LAZYNULL(preferences_to_show)
+
+    return ..()
+
+/datum/component/pref_viewer/Initialize(    
+	list/preferences_to_show
+)
+	if(!ismob(parent))
+		return COMPONENT_INCOMPATIBLE
+
+	for(var/datum/preference_info/pref as anything in preferences_to_show)
+		LAZYADD(src.preferences_to_show, new pref)
+
+/datum/component/pref_viewer/RegisterWithParent()
+	RegisterSignal(parent, COMSIG_MOB_RUN_EXAMINATE, PROC_REF(on_examine))
+
+/datum/component/pref_viewer/UnregisterFromParent()
+	UnregisterSignal(parent, COMSIG_MOB_RUN_EXAMINATE)
+
+/datum/component/pref_viewer/proc/on_examine(mob/source, mob/target, list/result)
+    SIGNAL_HANDLER
+
+    if(!istype(target) || !target.client)
+        return
+
+    INVOKE_ASYNC(src, PROC_REF(modify_examine), target, result)
+
+/datum/component/pref_viewer/proc/modify_examine(mob/target, list/result)
+	for(var/datum/preference_info/pref as anything in preferences_to_show)
+		var/datum/preference_toggle/toggle = pref.get_preference_toggle()
+
+		if(!HASBIT(target.client.prefs.toggles, toggle::preftoggle_bitflag) \
+        && !HASBIT(target.client.prefs.toggles2, toggle::preftoggle_bitflag)
+        )
+			continue
+
+		LAZYADD(result, pref.get_examine_text())

code/datums/mind.dm

@@ -2608,8 +2608,11 @@
  */
 /datum/mind/proc/remove_antag_datum(datum_type)
 	var/datum/antagonist/antag = has_antag_datum(datum_type)
-	if(antag)
-		qdel(antag)
+
+	if(!antag)
+		return
+
+	qdel(antag)
 
 
 /**

code/modules/antagonists/_common/antag_datum.dm

@@ -53,20 +53,32 @@ GLOBAL_LIST_EMPTY(antagonists)
 /datum/antagonist/Destroy(force)
 	for(var/datum/objective/objective as anything in objectives)
 		objectives -= objective
+
 		if(!objective.team)
 			qdel(objective)
+
 	remove_owner_from_gamemode()
 	GLOB.antagonists -= src
+
 	if(!silent)
 		farewell()
+
 	remove_innate_effects()
+
 	antag_memory = null
+
 	var/datum/team/team = get_team()
 	team?.remove_member(owner)
+
 	if(owner)
 		LAZYREMOVE(owner.antag_datums, src)
+
+		if(!LAZYLEN(owner.antag_datums)) // that one was the last antag datum.
+			handle_last_instance_removal()
+
 	restore_last_hud_and_role()
 	owner = null
+
 	return ..()
 
 
@@ -92,8 +104,15 @@ GLOBAL_LIST_EMPTY(antagonists)
 /datum/antagonist/proc/is_banned(mob/user)
 	if(!user)
 		return FALSE
+
 	return (jobban_isbanned(user, ROLE_SYNDICATE) || (job_rank && jobban_isbanned(user, job_rank)))
 
+/**
+ * When our datum was last and became removed. 
+ */
+/datum/antagonist/proc/handle_last_instance_removal()
+	return
+
 
 /**
  * Attempts to replace the role banned antag with a ghost player.

code/modules/antagonists/changeling/changeling_datum.dm

@@ -160,6 +160,17 @@ GLOBAL_LIST_INIT(possible_changeling_IDs, list("Alpha","Beta","Gamma","Delta","E
 	var/obj/item/organ/internal/brain/ling_brain = carbon_user.get_organ_slot(INTERNAL_ORGAN_BRAIN)
 	ling_brain?.decoy_brain = TRUE
 
+	user.AddComponent( \
+		/datum/component/pref_viewer, \
+		list(/datum/preference_info/take_out_of_the_round_without_obj), \
+	)
+
+/datum/antagonist/changeling/on_body_transfer(mob/living/old_body, mob/living/new_body)
+	. = ..()
+	qdel(old_body.GetComponent(/datum/component/pref_viewer))
+
+/datum/antagonist/changeling/handle_last_instance_removal()
+	qdel(owner.current.GetComponent(/datum/component/pref_viewer))
 
 /datum/antagonist/changeling/remove_innate_effects(mob/living/mob_override)
 	var/mob/living/user = ..()

code/modules/antagonists/space_ninja/ninja_datum.dm

@@ -114,6 +114,17 @@
 	var/mob/living/user = ..()
 	user.faction = list(ROLE_NINJA)
 
+	user.AddComponent( \
+		/datum/component/pref_viewer, \
+		list(/datum/preference_info/take_out_of_the_round_without_obj), \
+	)
+
+/datum/antagonist/ninja/handle_last_instance_removal()
+	qdel(owner.current.GetComponent(/datum/component/pref_viewer))
+
+/datum/antagonist/ninja/on_body_transfer(mob/living/old_body, mob/living/new_body)
+	. = ..()
+	qdel(old_body.GetComponent(/datum/component/pref_viewer))
 
 /datum/antagonist/ninja/proc/change_species(mob/living/mob_to_change = null) // This should be used to fully to remove robo-limbs & change species for lack of sprites
 	human_ninja = ishuman(mob_to_change) ? mob_to_change : null

code/modules/antagonists/traitor/datum_traitor.dm

@@ -38,6 +38,18 @@
 	datum_owner.AddComponent(/datum/component/codeword_hearing, GLOB.syndicate_code_phrase_regex, "codephrases", src)
 	datum_owner.AddComponent(/datum/component/codeword_hearing, GLOB.syndicate_code_response_regex, "coderesponses", src)
 
+	datum_owner.AddComponent( \
+		/datum/component/pref_viewer, \
+		list(/datum/preference_info/take_out_of_the_round_without_obj), \
+	)
+
+/datum/antagonist/traitor/on_body_transfer(mob/living/old_body, mob/living/new_body)
+	. = ..()
+	qdel(old_body.GetComponent(/datum/component/pref_viewer))
+
+/datum/antagonist/traitor/handle_last_instance_removal()
+	qdel(owner.current.GetComponent(/datum/component/pref_viewer))
+
 /datum/antagonist/traitor/remove_innate_effects(mob/living/mob_override)
 	. = ..()
 	var/mob/living/datum_owner = mob_override || owner.current

code/modules/antagonists/vampire/vampire_datum.dm

@@ -113,6 +113,17 @@
 			//slaved.leave_serv_hud(mob_override.mind)
 			//.mind.som = null
 
+	user.AddComponent( \
+		/datum/component/pref_viewer, \
+		list(/datum/preference_info/take_out_of_the_round_without_obj), \
+	)
+
+/datum/antagonist/vampire/on_body_transfer(mob/living/old_body, mob/living/new_body)
+	. = ..()
+	qdel(old_body.GetComponent(/datum/component/pref_viewer))
+
+/datum/antagonist/vampire/handle_last_instance_removal()
+	qdel(owner.current.GetComponent(/datum/component/pref_viewer))
 
 /datum/antagonist/vampire/remove_innate_effects(mob/living/mob_override, transformation = FALSE)
 	var/mob/living/user = ..()