To Whom It May Concern - Bullet Writing (#3552)

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## About The Pull Request

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You can now write on bullets with a pen to give your ~~victim~~
recipient a lovely message when they're hit.


![image](https://github.com/user-attachments/assets/859b62ac-5597-40f2-bc70-59bb6091015e)


## Why It's Good For The Game

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benefit the game. If you can't justify it in words, it might not be
worth adding. -->

Adds a little personalization to your death dealing, and I think it'd be
funny.
## Changelog

:cl:
add: Bullets can have a message written on them.
/:cl:

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code/modules/projectiles/ammunition/_ammo_casing.dm

@@ -51,7 +51,20 @@
 	var/stack_size = 12
 
 /obj/item/ammo_casing/attackby(obj/item/attacking_item, mob/user, params)
-	if(istype(attacking_item, /obj/item/ammo_box) && user.is_holding(src))
+	if(istype(attacking_item, /obj/item/pen))
+		if(!user.is_literate())
+			to_chat(user, "<span class='notice'>You scribble illegibly on the [src]!</span>")
+			return
+		var/inputvalue = stripped_input(user, "What would you like to label the round?", "Bullet Labelling", "", MAX_NAME_LEN)
+
+		if(!inputvalue)
+			return
+
+		if(user.canUseTopic(src, BE_CLOSE))
+			name = "[initial(src.name)][(inputvalue ? " - '[inputvalue]'" : null)]"
+			if(BB)
+				BB.name = "[initial(BB.name)][(inputvalue ? " - '[inputvalue]'" : null)]"
+	else if(istype(attacking_item, /obj/item/ammo_box) && user.is_holding(src))
 		add_fingerprint(user)
 		var/obj/item/ammo_box/ammo_box = attacking_item
 		var/obj/item/ammo_casing/other_casing = ammo_box.get_round(TRUE)
@@ -92,6 +105,10 @@
 
 	return ..()
 
+/obj/item/ammo_casing/examine(mob/user)
+	. = ..()
+	span_notice("You could write a message on \the [src] by writing on it with a pen.")
+
 /obj/item/ammo_casing/proc/try_stacking(obj/item/ammo_casing/other_casing, mob/living/user)
 	if(user)
 		add_fingerprint(user)