Adds hats to dionaea.

code/modules/clothing/clothing.dm

@@ -276,15 +276,39 @@ BLIND     // can't see anything
 	user.update_action_buttons()
 
 /obj/item/clothing/head/attack_ai(var/mob/user)
-	if(Adjacent(user) && istype(user, /mob/living/silicon/robot/drone))
+	if(!mob_wear_hat(user))
+		return ..()
+
+/obj/item/clothing/head/attack_generic(var/mob/user)
+	if(!mob_wear_hat(user))
+		return ..()
+
+/obj/item/clothing/head/proc/mob_wear_hat(var/mob/user)
+	if(!Adjacent(user))
+		return 0
+	var/success
+	if(istype(user, /mob/living/silicon/robot/drone))
 		var/mob/living/silicon/robot/drone/D = user
-		if(!D.hat)
-			D.wear_hat(src)
-			D << "<span class='notice'>You crawl under \the [src].</span>"
+		if(D.hat)
+			success = 2
 		else
-			D << "<span class='warning'>You are already wearing \the [D.hat].</span>"
-		return
-	return ..()
+			D.wear_hat(src)
+			success = 1
+	else if(istype(user, /mob/living/carbon/alien/diona))
+		var/mob/living/carbon/alien/diona/D = user
+		if(D.hat)
+			success = 2
+		else
+			D.wear_hat(src)
+			success = 1
+
+	if(!success)
+		return 0
+	else if(success == 2)
+		user << "<span class='warning'>You are already wearing a hat.</span>"
+	else if(success == 1)
+		user << "<span class='notice'>You crawl under \the [src].</span>"
+	return 1
 
 /obj/item/clothing/head/update_icon(var/mob/user)
 

code/modules/mob/living/carbon/alien/diona/diona.dm

@@ -9,6 +9,7 @@
 	universal_understand = 1
 	universal_speak = 0      // Dionaea do not need to speak to people other than other dionaea.
 	holder_type = /obj/item/weapon/holder/diona
+	var/obj/item/hat
 
 /mob/living/carbon/alien/diona/New()
 
@@ -32,3 +33,10 @@
 /mob/living/carbon/alien/diona/put_in_hands(var/obj/item/W) // No hands.
 	W.loc = get_turf(src)
 	return 1
+
+/mob/living/carbon/alien/diona/proc/wear_hat(var/obj/item/new_hat)
+	if(hat)
+		return
+	hat = new_hat
+	new_hat.loc = src
+	update_icons()

code/modules/mob/living/carbon/alien/diona/diona_attacks.dm

@@ -6,5 +6,22 @@
 			return
 		get_scooped(H)
 		return
+	else if(H.a_intent == "grab" && hat && !(H.l_hand && H.r_hand))
+		hat.loc = get_turf(src)
+		H.put_in_hands(hat)
+		H.visible_message("<span class='danger'>\The [H] removes \the [src]'s [hat].</span>")
+		hat = null
+		update_icons()
 	else
 		return ..()
+
+/mob/living/carbon/alien/diona/attackby(var/obj/item/weapon/W, var/mob/user)
+	if(user.a_intent == "help" && istype(W, /obj/item/clothing/head))
+		if(hat)
+			user << "<span class='warning'>\The [src] is already wearing \the [hat].</span>"
+			return
+		user.unEquip(W)
+		wear_hat(W)
+		user.visible_message("<span class='notice'>\The [user] puts \the [W] on \the [src].</span>")
+		return
+	return ..()

code/modules/mob/living/carbon/alien/diona/update_icons.dm

@@ -6,3 +6,7 @@
 		icon_state = "[initial(icon_state)]_sleep"
 	else
 		icon_state = "[initial(icon_state)]"
+
+	overlays.Cut()
+	if(hat)
+		overlays |= get_hat_icon(hat, 0, -8)

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

@@ -1,4 +1,22 @@
-var/list/drone_hat_cache = list()
+var/list/mob_hat_cache = list()
+/proc/get_hat_icon(var/obj/item/hat, var/offset_x = 0, var/offset_y = 0)
+	var/t_state = hat.icon_state
+	if(hat.item_state_slots && hat.item_state_slots[slot_head_str])
+		t_state = hat.item_state_slots[slot_head_str]
+	else if(hat.item_state)
+		t_state = hat.item_state
+	var/key = "[t_state]_[offset_x]_[offset_y]"
+	if(!mob_hat_cache[key])            // Not ideal as there's no guarantee all hat icon_states
+		var/t_icon = INV_HEAD_DEF_ICON // are unique across multiple dmis, but whatever.
+		if(hat.icon_override)
+			t_icon = hat.icon_override
+		else if(hat.item_icons && (slot_head_str in hat.item_icons))
+			t_icon = hat.item_icons[slot_head_str]
+		var/image/I = image(icon = t_icon, icon_state = t_state)
+		I.pixel_x = offset_x
+		I.pixel_y = offset_y
+		mob_hat_cache[key] = I
+	return mob_hat_cache[key]
 
 /mob/living/silicon/robot/drone
 	name = "drone"
@@ -101,26 +119,8 @@ var/list/drone_hat_cache = list()
 		overlays += "eyes-[icon_state]"
 	else
 		overlays -= "eyes"
-
-	if(hat)
-		// Copied from human inventory.
-		// Let the drones wear hats.
-		var/t_state = hat.icon_state
-		if(hat.item_state_slots && hat.item_state_slots[slot_head_str])
-			t_state = hat.item_state_slots[slot_head_str]
-		else if(hat.item_state)
-			t_state = hat.item_state
-		if(!drone_hat_cache["[t_state]-[icon_state]"]) // Not ideal as there's no guarantee all hat icon_states
-			var/t_icon = INV_HEAD_DEF_ICON             // are unique across multiple dmis, but whatever.
-			if(hat.icon_override)
-				t_icon = hat.icon_override
-			else if(hat.item_icons && (slot_head_str in hat.item_icons))
-				t_icon = hat.item_icons[slot_head_str]
-			var/image/I = image(icon = t_icon, icon_state = t_state)
-			I.pixel_x = hat_x_offset
-			I.pixel_y = hat_y_offset
-			drone_hat_cache[t_state] = I
-		overlays |= drone_hat_cache[t_state]
+	if(hat) // Let the drones wear hats.
+		overlays |= get_hat_icon(hat, hat_x_offset, hat_y_offset)
 
 /mob/living/silicon/robot/drone/choose_icon()
 	return