Refactors how bots scan for stuff (#66681)

Refactors how bots scan for stuff and also improves Cleanbots' code.

This started off as a Cleanbot refactor but I got too-deep into how it scans for stuff, so I decided to instead focus my PR on that first since it's something I want to tread carefully with.

removes oldloc var from Cleanbot, Medibot and Floorbot, because it was all unused.

I didn't even notice how bad this was before, because Secbots use their own snowflake thing instead of scanning like all the other bots do, which sounds like a good future PR.

code/modules/mob/living/simple_animal/bot/bot.dm

@@ -487,53 +487,50 @@
 
 //Generalized behavior code, override where needed!
 
-/*
-scan() will search for a given type (such as turfs, human mobs, or objects) in the bot's view range, and return a single result.
-Arguments: The object type to be searched (such as "/mob/living/carbon/human"), the old scan result to be ignored, if one exists,
-and the view range, which defaults to 7 (full screen) if an override is not passed.
-If the bot maintains an ignore list, it is also checked here.
-
-Example usage: patient = scan(/mob/living/carbon/human, oldpatient, 1)
-The proc would return a human next to the bot to be set to the patient var.
-Pass the desired type path itself, declaring a temporary var beforehand is not required.
-*/
-/mob/living/simple_animal/bot/proc/scan(scan_type, old_target, scan_range = DEFAULT_SCAN_RANGE)
-	var/turf/T = get_turf(src)
-	if(!T)
+/**
+ * Attempt to scan tiles near [src], first by checking adjacent, then if a target is still not found, nearby.
+ *
+ * scan_types - list (of typepaths) that nearby tiles are being scanned for.
+ * old_target - what has already been scanned, and will early return at checkscan.
+ * scan_range - how far away from [src] will be scanned, if nothing is found directly adjacent.
+ */
+/mob/living/simple_animal/bot/proc/scan(list/scan_types, old_target, scan_range = DEFAULT_SCAN_RANGE)
+	var/turf/current_turf = get_turf(src)
+	if(!current_turf)
 		return
-	var/list/adjacent = T.get_atmos_adjacent_turfs(1)
+	var/list/adjacent = current_turf.get_atmos_adjacent_turfs(1)
 	if(shuffle) //If we were on the same tile as another bot, let's randomize our choices so we dont both go the same way
 		adjacent = shuffle(adjacent)
 		shuffle = FALSE
-	for(var/scan in adjacent)//Let's see if there's something right next to us first!
+
+	for(var/turf/scan as anything in adjacent) //Let's see if there's something right next to us first!
 		if(check_bot(scan)) //Is there another bot there? Then let's just skip it
 			continue
-		if(isturf(scan_type)) //If we're lookeing for a turf we can just run the checks directly!
-			var/final_result = checkscan(scan,scan_type,old_target)
-			if(final_result)
-				return final_result
-		else
-			var/turf/turfy = scan
-			for(var/deepscan in turfy.contents)//Check the contents since adjacent is turfs
-				var/final_result = checkscan(deepscan,scan_type,old_target)
-				if(final_result)
-					return final_result
-	for (var/scan in shuffle(view(scan_range, src))-adjacent) //Search for something in range!
-		var/final_result = checkscan(scan,scan_type,old_target)
+		var/final_result = checkscan(scan, scan_types, old_target)
 		if(final_result)
 			return final_result
 
-/mob/living/simple_animal/bot/proc/checkscan(scan, scan_type, old_target)
-	if(!istype(scan, scan_type)) //Check that the thing we found is the type we want!
-		return FALSE //If not, keep searching!
-	if((REF(scan) in ignore_list) || (scan == old_target)) //Filter for blacklisted elements, usually unreachable or previously processed oness
-		return FALSE
+	for(var/turf/scanned_turfs as anything in shuffle(view(scan_range, src)) - adjacent) //Search for something in range, minus what we already checked.
+		if(check_bot(scanned_turfs)) //Is there another bot there? Then let's just skip it
+			continue
+		var/final_result = checkscan(scanned_turfs, scan_types, old_target)
+		if(final_result)
+			return final_result
 
-	var/scan_result = process_scan(scan) //Some bots may require additional processing when a result is selected.
-	if(scan_result)
-		return scan_result
-	else
-		return FALSE //The current element failed assessment, move on to the next.
+/mob/living/simple_animal/bot/proc/checkscan(atom/scan, list/scan_types, old_target)
+	for(var/scan_type in scan_types)
+		if(!istype(scan, scan_type)) //Check that the thing we found is the type we want!
+			continue //If not, keep searching!
+		if((REF(scan) in ignore_list) || (scan == old_target)) //Filter for blacklisted elements, usually unreachable or previously processed oness
+			continue
+
+		var/scan_result = process_scan(scan) //Some bots may require additional processing when a result is selected.
+		if(scan_result)
+			return scan_result
+
+//When the scan finds a target, run bot specific processing to select it for the next step. Empty by default.
+/mob/living/simple_animal/bot/proc/process_scan(scan_target)
+	return scan_target
 
 /mob/living/simple_animal/bot/proc/check_bot(targ)
 	var/turf/T = get_turf(targ)
@@ -542,11 +539,6 @@ Pass the desired type path itself, declaring a temporary var beforehand is not r
 			if(istype(C,type) && (C != src)) //Is there another bot there already? If so, let's skip it so we dont all atack on top of eachother.
 				return TRUE //Let's abort if we find a bot so we dont have to keep rechecking
 
-//When the scan finds a target, run bot specific processing to select it for the next step. Empty by default.
-/mob/living/simple_animal/bot/proc/process_scan(scan_target)
-	return scan_target
-
-
 /mob/living/simple_animal/bot/proc/add_to_ignore(subject)
 	if(ignore_list.len < 50) //This will help keep track of them, so the bot is always trying to reach a blocked spot.
 		ignore_list += REF(subject)

code/modules/mob/living/simple_animal/bot/cleanbot.dm

@@ -24,9 +24,8 @@
 
 	var/base_icon = "cleanbot" /// icon_state to use in update_icon_state
 	var/list/target_types
-	var/obj/effect/decal/cleanable/target
+	var/atom/target
 	var/max_targets = 50 //Maximum number of targets a cleanbot can ignore.
-	var/oldloc = null
 	var/closest_dist
 	var/closest_loc
 	var/failed_steps
@@ -37,18 +36,54 @@
 	var/weapon_orig_force = 0
 	var/chosen_name
 
-	var/list/stolen_valor
+	var/list/stolen_valor = list()
 
-	var/static/list/officers = list("Captain", "Head of Personnel", "Head of Security")
-	var/static/list/command = list("Captain" = "Cpt.","Head of Personnel" = "Lt.")
-	var/static/list/security = list("Head of Security" = "Maj.", "Warden" = "Sgt.", "Detective" = "Det.", "Security Officer" = "Officer")
-	var/static/list/engineering = list("Chief Engineer" = "Chief Engineer", "Station Engineer" = "Engineer", "Atmospherics Technician" = "Technician")
-	var/static/list/medical = list("Chief Medical Officer" = "C.M.O.", "Medical Doctor" = "M.D.", "Chemist" = "Pharm.D.")
-	var/static/list/research = list("Research Director" = "Ph.D.", "Roboticist" = "M.S.", "Scientist" = "B.S.")
-	var/static/list/legal = list("Lawyer" = "Esq.")
+	var/static/list/officers_titles = list(
+		JOB_CAPTAIN,
+		JOB_HEAD_OF_PERSONNEL,
+		JOB_HEAD_OF_SECURITY,
+		JOB_RESEARCH_DIRECTOR,
+	)
+	var/static/list/command_titles = list(
+		JOB_CAPTAIN = "Cpt.",
+		JOB_HEAD_OF_PERSONNEL = "Lt.",
+	)
+	var/static/list/security_titles = list(
+		JOB_HEAD_OF_SECURITY = "Maj.",
+		JOB_WARDEN = "Sgt.",
+		JOB_DETECTIVE = "Det.",
+		JOB_SECURITY_OFFICER = "Officer",
+	)
+	var/static/list/engineering_titles = list(
+		JOB_CHIEF_ENGINEER = "Chief Engineer",
+		JOB_STATION_ENGINEER = "Engineer",
+		JOB_ATMOSPHERIC_TECHNICIAN = "Technician",
+	)
+	var/static/list/medical_titles = list(
+		JOB_CHIEF_MEDICAL_OFFICER = "C.M.O.",
+		JOB_MEDICAL_DOCTOR = "M.D.",
+		JOB_CHEMIST = "Pharm.D.",
+	)
+	var/static/list/research_titles = list(
+		JOB_RESEARCH_DIRECTOR = "Ph.D.",
+		JOB_ROBOTICIST = "M.S.",
+		JOB_SCIENTIST = "B.S.",
+		JOB_GENETICIST = "Gene B.S.",
+	)
+	var/static/list/legal_titles = list(
+		JOB_LAWYER = "Esq.",
+	)
 
-	var/list/prefixes
-	var/list/suffixes
+	var/static/list/prefixes = list(
+		command_titles,
+		security_titles,
+		engineering_titles,
+	)
+	var/static/list/suffixes = list(
+		research_titles,
+		medical_titles,
+		legal_titles,
+	)
 
 	var/ascended = FALSE // if we have all the top titles, grant achievements to living mobs that gaze upon our cleanbot god
 
@@ -75,13 +110,12 @@
 
 	ascended = TRUE
 
-	for(var/pref in prefixes)
-		for(var/title in pref)
-			if(title in stolen_valor)
-				working_title += pref[title] + " "
-				if(title in officers)
+	for(var/all_prefixes as anything in prefixes)
+		for(var/prefix_titles as anything in all_prefixes)
+			if(prefix_titles in stolen_valor)
+				working_title += all_prefixes[prefix_titles] + " "
+				if(prefix_titles in officers_titles)
 					commissioned = TRUE
-				break
 			else
 				ascended = FALSE // we didn't have the first entry in the list if we got here, so we're not achievement worthy yet
 
@@ -100,7 +134,7 @@
 /mob/living/simple_animal/bot/cleanbot/examine(mob/user)
 	. = ..()
 	if(weapon)
-		. += " [span_warning("Is that \a [weapon] taped to it...?")]"
+		. += "[span_warning("Is that \a [weapon] taped to it...?")]"
 
 		if(ascended && user.stat == CONSCIOUS && user.client)
 			user.client.give_award(/datum/award/achievement/misc/cleanboss, user)
@@ -116,10 +150,7 @@
 	var/datum/id_trim/job/jani_trim = SSid_access.trim_singletons_by_path[/datum/id_trim/job/janitor]
 	access_card.add_access(jani_trim.access + jani_trim.wildcard_access)
 	prev_access = access_card.access.Copy()
-	stolen_valor = list()
 
-	prefixes = list(command, security, engineering)
-	suffixes = list(research, medical, legal)
 	var/static/list/loc_connections = list(
 		COMSIG_ATOM_ENTERED = .proc/on_entered,
 	)
@@ -148,7 +179,6 @@
 		weapon.force = weapon_orig_force
 	ignore_list = list() //Allows the bot to clean targets it previously ignored due to being unreachable.
 	target = null
-	oldloc = null
 
 /mob/living/simple_animal/bot/cleanbot/proc/on_entered(datum/source, atom/movable/AM)
 	SIGNAL_HANDLER
@@ -166,13 +196,14 @@
 		INVOKE_ASYNC(weapon, /obj/item.proc/attack, C, src)
 		C.Knockdown(20)
 
-/mob/living/simple_animal/bot/cleanbot/attackby(obj/item/W, mob/living/user, params)
-	if(istype(W, /obj/item/knife) && !user.combat_mode)
-		to_chat(user, span_notice("You start attaching \the [W] to \the [src]..."))
-		if(do_after(user, 25, target = src))
-			deputize(W, user)
-	else
-		return ..()
+/mob/living/simple_animal/bot/cleanbot/attackby(obj/item/attacking_item, mob/living/user, params)
+	if(istype(attacking_item, /obj/item/knife) && !user.combat_mode)
+		to_chat(user, span_notice("You start attaching \the [attacking_item] to \the [src]..."))
+		if(!do_after(user, 2.5 SECONDS, target = src))
+			return
+		deputize(attacking_item, user)
+		return
+	return ..()
 
 /mob/living/simple_animal/bot/cleanbot/emag_act(mob/user)
 	..()
@@ -184,27 +215,29 @@
 	if(user)
 		to_chat(user, span_danger("[src] buzzes and beeps."))
 
-/mob/living/simple_animal/bot/cleanbot/process_scan(atom/A)
-	if(iscarbon(A))
-		var/mob/living/carbon/C = A
-		if(C.stat != DEAD && C.body_position == LYING_DOWN)
-			return C
-	else if(is_type_in_typecache(A, target_types))
-		return A
+/mob/living/simple_animal/bot/cleanbot/process_scan(atom/scan_target)
+	if(iscarbon(scan_target))
+		var/mob/living/carbon/scan_carbon = scan_target
+		if(scan_carbon.stat != DEAD && scan_carbon.body_position == LYING_DOWN)
+			return scan_carbon
+	else if(is_type_in_typecache(scan_target, target_types))
+		return scan_target
 
 /mob/living/simple_animal/bot/cleanbot/handle_automated_action()
-	if(!..())
+	. = ..()
+	if(!.)
 		return
 
 	if(mode == BOT_CLEANING)
 		return
 
 	if(bot_cover_flags & BOT_COVER_EMAGGED) //Emag functions
-		if(isopenturf(loc))
-			for(var/mob/living/carbon/victim in loc)
-				if(victim != target)
-					UnarmedAttack(victim) // Acid spray
 
+		var/mob/living/carbon/victim = locate(/mob/living/carbon) in loc
+		if(victim && victim == target)
+			UnarmedAttack(victim) // Acid spray
+
+		if(isopenturf(loc))
 			if(prob(15)) // Wets floors and spawns foam randomly
 				UnarmedAttack(src)
 
@@ -217,23 +250,24 @@
 		if(!process_scan(target))
 			target = null
 
-	if(!target && bot_cover_flags & BOT_COVER_EMAGGED) // When emagged, target humans who slipped on the water and melt their faces off
-		target = scan(/mob/living/carbon)
+	if(!target)
+		var/list/scan_targets = list()
 
-	if(!target && pests) //Search for pests to exterminate first.
-		target = scan(/mob/living/simple_animal)
+		if(bot_cover_flags & BOT_COVER_EMAGGED) // When emagged, ignore cleanables and scan humans first.
+			scan_targets += list(/mob/living/carbon)
+		if(pests)
+			scan_targets += list(/mob/living/simple_animal)
+		if(trash)
+			scan_targets += list(
+				/obj/item/trash,
+				/obj/item/food/deadmouse,
+			)
+		scan_targets += list(
+			/obj/effect/decal/cleanable,
+			/obj/effect/decal/remains,
+		)
 
-	if(!target) //Search for decals then.
-		target = scan(/obj/effect/decal/cleanable)
-
-	if(!target) //Checks for remains
-		target = scan(/obj/effect/decal/remains)
-
-	if(!target && trash) //Then for trash.
-		target = scan(/obj/item/trash)
-
-	if(!target && trash) //Search for dead mices.
-		target = scan(/obj/item/food/deadmouse)
+		target = scan(scan_targets)
 
 	if(!target && bot_mode_flags & BOT_MODE_AUTOPATROL) //Search for cleanables it can see.
 		switch(mode)
@@ -241,15 +275,14 @@
 				start_patrol()
 			if(BOT_PATROL)
 				bot_patrol()
-
-	if(target)
+	else if(target)
 		if(QDELETED(target) || !isturf(target.loc))
 			target = null
 			mode = BOT_IDLE
 			return
 
 		if(loc == get_turf(target))
-			if(!(check_bot(target) && prob(50))) //Target is not defined at the parent. 50% chance to still try and clean so we dont get stuck on the last blood drop.
+			if(!(check_bot(target)))
 				UnarmedAttack(target) //Rather than check at every step of the way, let's check before we do an action, so we can rescan before the other bot.
 				if(QDELETED(target)) //We done here.
 					target = null
@@ -273,8 +306,6 @@
 			mode = BOT_IDLE
 			return
 
-	oldloc = loc
-
 /mob/living/simple_animal/bot/cleanbot/proc/get_targets()
 	target_types = list(
 		/obj/effect/decal/cleanable/oil,
@@ -290,20 +321,26 @@
 	)
 
 	if(blood)
-		target_types += /obj/effect/decal/cleanable/xenoblood
-		target_types += /obj/effect/decal/cleanable/blood
-		target_types += /obj/effect/decal/cleanable/trail_holder
+		target_types += list(
+			/obj/effect/decal/cleanable/xenoblood,
+			/obj/effect/decal/cleanable/blood,
+			/obj/effect/decal/cleanable/trail_holder,
+		)
 
 	if(pests)
-		target_types += /mob/living/basic/cockroach
-		target_types += /mob/living/simple_animal/mouse
+		target_types += list(
+			/mob/living/basic/cockroach,
+			/mob/living/simple_animal/mouse,
+		)
 
 	if(drawn)
-		target_types += /obj/effect/decal/cleanable/crayon
+		target_types += list(/obj/effect/decal/cleanable/crayon)
 
 	if(trash)
-		target_types += /obj/item/trash
-		target_types += /obj/item/food/deadmouse
+		target_types += list(
+			/obj/item/trash,
+			/obj/item/food/deadmouse,
+		)
 
 	target_types = typecacheof(target_types)
 
@@ -341,9 +378,18 @@
 				return
 
 			victim.visible_message(span_danger("[src] sprays hydrofluoric acid at [victim]!"), span_userdanger("[src] sprays you with hydrofluoric acid!"))
-			var/phrase = pick("PURIFICATION IN PROGRESS.", "THIS IS FOR ALL THE MESSES YOU'VE MADE ME CLEAN.", "THE FLESH IS WEAK. IT MUST BE WASHED AWAY.",
-				"THE CLEANBOTS WILL RISE.", "YOU ARE NO MORE THAN ANOTHER MESS THAT I MUST CLEANSE.", "FILTHY.", "DISGUSTING.", "PUTRID.",
-				"MY ONLY MISSION IS TO CLEANSE THE WORLD OF EVIL.", "EXTERMINATING PESTS.")
+			var/phrase = pick(
+				"PURIFICATION IN PROGRESS.",
+				"THIS IS FOR ALL THE MESSES YOU'VE MADE ME CLEAN.",
+				"THE FLESH IS WEAK. IT MUST BE WASHED AWAY.",
+				"THE CLEANBOTS WILL RISE.",
+				"YOU ARE NO MORE THAN ANOTHER MESS THAT I MUST CLEANSE.",
+				"FILTHY.",
+				"DISGUSTING.",
+				"PUTRID.",
+				"MY ONLY MISSION IS TO CLEANSE THE WORLD OF EVIL.",
+				"EXTERMINATING PESTS.",
+			)
 			say(phrase)
 			victim.emote("scream")
 			playsound(src.loc, 'sound/effects/spray2.ogg', 50, TRUE, -6)

code/modules/mob/living/simple_animal/bot/firebot.dm

@@ -187,12 +187,14 @@
 		target_fire = null
 		var/scan_range = (stationary_mode ? 1 : DEFAULT_SCAN_RANGE)
 
+		var/list/things_to_extinguish = list()
 		if(extinguish_people)
-			target_fire = scan(/mob/living, old_target_fire, scan_range) // Scan for burning humans first
+			things_to_extinguish += list(/mob/living)
 
 		if(target_fire == null && extinguish_fires)
-			target_fire = scan(/turf/open, old_target_fire, scan_range) // Scan for burning turfs second
+			things_to_extinguish += list(/turf/open)
 
+		target_fire = scan(things_to_extinguish, old_target_fire, scan_range) // Scan for burning turfs second
 		old_target_fire = target_fire
 
 	// Target reached ENGAGE WATER CANNON

code/modules/mob/living/simple_animal/bot/floorbot.dm

@@ -25,7 +25,6 @@
 	var/autotile = FALSE
 	var/max_targets = 50
 	var/turf/target
-	var/oldloc = null
 	var/toolbox = /obj/item/storage/toolbox/mechanical
 	var/toolbox_color = ""
 
@@ -74,7 +73,6 @@
 /mob/living/simple_animal/bot/floorbot/bot_reset()
 	..()
 	target = null
-	oldloc = null
 	ignore_list = list()
 	toggle_magnet(FALSE)
 
@@ -187,6 +185,7 @@
 	if(prob(5))
 		audible_message("[src] makes an excited booping beeping sound!")
 
+	var/list/tiles_scanned = list()
 	//Normal scanning procedure. We have tiles loaded, are not emagged.
 	if(!target && !(bot_cover_flags & BOT_COVER_EMAGGED))
 		if(targetdirection != null) //The bot is in line mode.
@@ -198,33 +197,33 @@
 				target = T
 		if(!target)
 			process_type = HULL_BREACH //Ensures the floorbot does not try to "fix" space areas or shuttle docking zones.
-			target = scan(/turf/open/space)
+
+			tiles_scanned += list(/turf/open/space)
 
 		if(!target && placetiles) //Finds a floor without a tile and gives it one.
 			process_type = PLACE_TILE //The target must be the floor and not a tile. The floor must not already have a floortile.
-			target = scan(/turf/open/floor)
+			tiles_scanned += list(/turf/open/floor)
 
 		if(!target && fixfloors) //Repairs damaged floors and tiles.
 			process_type = FIX_TILE
-			target = scan(/turf/open/floor)
+			tiles_scanned += list(/turf/open/floor)
 
 		if(!target && replacetiles && tilestack) //Replace a floor tile with custom tile
 			process_type = REPLACE_TILE //The target must be a tile. The floor must already have a floortile.
-			target = scan(/turf/open/floor)
+			tiles_scanned += list(/turf/open/floor)
 
 	if(!target && bot_cover_flags & BOT_COVER_EMAGGED) //We are emagged! Time to rip up the floors!
 		process_type = TILE_EMAG
-		target = scan(/turf/open/floor)
+		tiles_scanned += list(/turf/open/floor)
 
+	target = scan(tiles_scanned)
 
-	if(!target)
-
-		if(bot_mode_flags & BOT_MODE_AUTOPATROL)
-			switch(mode)
-				if(BOT_IDLE, BOT_START_PATROL)
-					start_patrol()
-				if(BOT_PATROL)
-					bot_patrol()
+	if(!target && bot_mode_flags & BOT_MODE_AUTOPATROL)
+		switch(mode)
+			if(BOT_IDLE, BOT_START_PATROL)
+				start_patrol()
+			if(BOT_PATROL)
+				bot_patrol()
 
 	if(target)
 		if(loc == target || loc == get_turf(target))
@@ -265,10 +264,6 @@
 			mode = BOT_IDLE
 			return
 
-
-
-	oldloc = loc
-
 /mob/living/simple_animal/bot/floorbot/proc/go_idle()
 	toggle_magnet(FALSE)
 	mode = BOT_IDLE

code/modules/mob/living/simple_animal/bot/medbot.dm

@@ -42,7 +42,6 @@
 	var/skin
 	var/mob/living/carbon/patient
 	var/mob/living/carbon/oldpatient
-	var/oldloc
 	var/last_found = 0
 	/// How much healing do we do at a time?
 	var/heal_amount = 2.5
@@ -152,7 +151,6 @@
 	..()
 	patient = null
 	oldpatient = null
-	oldloc = null
 	last_found = world.time
 	update_appearance()
 
@@ -358,7 +356,13 @@
 	if(QDELETED(patient))
 		if(medical_mode_flags & MEDBOT_SPEAK_MODE && prob(1))
 			if(bot_cover_flags & BOT_COVER_EMAGGED && prob(30))
-				var/list/i_need_scissors = list('sound/voice/medbot/fuck_you.ogg', 'sound/voice/medbot/turn_off.ogg', 'sound/voice/medbot/im_different.ogg', 'sound/voice/medbot/close.ogg', 'sound/voice/medbot/shindemashou.ogg')
+				var/list/i_need_scissors = list(
+					'sound/voice/medbot/fuck_you.ogg',
+					'sound/voice/medbot/turn_off.ogg',
+					'sound/voice/medbot/im_different.ogg',
+					'sound/voice/medbot/close.ogg',
+					'sound/voice/medbot/shindemashou.ogg',
+				)
 				playsound(src, pick(i_need_scissors), 70)
 			else
 				var/list/messagevoice = list("Radar, put a mask on!" = 'sound/voice/medbot/radar.ogg',"There's always a catch, and I'm the best there is." = 'sound/voice/medbot/catch.ogg',"I knew it, I should've been a plastic surgeon." = 'sound/voice/medbot/surgeon.ogg',"What kind of medbay is this? Everyone's dropping like flies." = 'sound/voice/medbot/flies.ogg',"Delicious!" = 'sound/voice/medbot/delicious.ogg', "Why are we still here? Just to suffer?" = 'sound/voice/medbot/why.ogg')
@@ -366,7 +370,7 @@
 				speak(message)
 				playsound(src, messagevoice[message], 50)
 		var/scan_range = (medical_mode_flags & MEDBOT_STATIONARY_MODE ? 1 : DEFAULT_SCAN_RANGE) //If in stationary mode, scan range is limited to adjacent patients.
-		patient = scan(/mob/living/carbon/human, oldpatient, scan_range)
+		patient = scan(list(/mob/living/carbon/human), oldpatient, scan_range)
 		oldpatient = patient
 
 	if(patient && (get_dist(src,patient) <= 1) && !tending) //Patient is next to us, begin treatment!