From 46f1a09018d7cadd3bf49a6aa385ef7d92e3595f Mon Sep 17 00:00:00 2001
From: larentoun <31931237+larentoun@users.noreply.github.com>
Date: Thu, 6 Jun 2024 23:24:26 +0300
Subject: [PATCH] Only one IV bag at a time (#25805)

* single iv bag

* add to traits.dm

* comment for called signal
---
 code/__HELPERS/trait_helpers.dm                    |  1 +
 code/_globalvars/traits.dm                         |  1 +
 code/modules/reagents/reagent_containers/iv_bag.dm | 11 +++++++++++
 3 files changed, 13 insertions(+)

diff --git a/code/__HELPERS/trait_helpers.dm b/code/__HELPERS/trait_helpers.dm
index 85eff70a89a..21d632a2e45 100644
--- a/code/__HELPERS/trait_helpers.dm
+++ b/code/__HELPERS/trait_helpers.dm
@@ -234,6 +234,7 @@ Remember to update _globalvars/traits.dm if you're adding/removing/renaming trai
 #define TRAIT_ABSTRACT_HANDS "abstract_hands" // Mobs with this trait can only pick up abstract items.
 #define TRAIT_SLOW_GRABBER "slow_grabber" // Adds a 1.5 * CLICK_CD_MELEE delay to upgrading into a aggressive grab.
 #define TRAIT_LANGUAGE_LOCKED "language_locked" // cant add/remove languages until removed (excludes babel because fuck everything i guess)
+#define TRAIT_HAS_IV_BAG "iv_bag" // Used to check if there is an active IV bag. Currently blocks another IV bags from being inserted.
 
 //***** MIND TRAITS *****/
 #define TRAIT_HOLY "is_holy" // The mob is holy in regards to religion
diff --git a/code/_globalvars/traits.dm b/code/_globalvars/traits.dm
index cf78a9c78dd..48c993c8bf2 100644
--- a/code/_globalvars/traits.dm
+++ b/code/_globalvars/traits.dm
@@ -97,6 +97,7 @@ GLOBAL_LIST_INIT(traits_by_type, list(
 		"TRAIT_ABSTRACT_HANDS" = TRAIT_ABSTRACT_HANDS,
 		"TRAIT_SLOW_GRABBER" = TRAIT_SLOW_GRABBER,
 		"TRAIT_LANGUAGE_LOCKED" = TRAIT_LANGUAGE_LOCKED,
+		"TRAIT_HAS_IV_BAG" = TRAIT_HAS_IV_BAG
 	),
 
 	/datum/mind = list(
diff --git a/code/modules/reagents/reagent_containers/iv_bag.dm b/code/modules/reagents/reagent_containers/iv_bag.dm
index d2d0de9697f..9bee791230f 100644
--- a/code/modules/reagents/reagent_containers/iv_bag.dm
+++ b/code/modules/reagents/reagent_containers/iv_bag.dm
@@ -41,11 +41,19 @@
 	..()
 	update_icon(UPDATE_OVERLAYS)
 
+/obj/item/reagent_containers/iv_bag/proc/on_examine(datum/source, mob/examiner, list/examine_list)
+	SIGNAL_HANDLER // COMSIG_PARENT_EXAMINE
+	examine_list += "<span class='notice'>[source.p_they(TRUE)] [source.p_have()] an active IV bag.</span>"
+
 /obj/item/reagent_containers/iv_bag/proc/begin_processing(mob/target)
 	injection_target = target
+	ADD_TRAIT(injection_target, TRAIT_HAS_IV_BAG, UID())
+	RegisterSignal(injection_target, COMSIG_PARENT_EXAMINE, PROC_REF(on_examine))
 	START_PROCESSING(SSobj, src)
 
 /obj/item/reagent_containers/iv_bag/proc/end_processing()
+	REMOVE_TRAIT(injection_target, TRAIT_HAS_IV_BAG, UID())
+	UnregisterSignal(injection_target, COMSIG_PARENT_EXAMINE)
 	injection_target = null
 	STOP_PROCESSING(SSobj, src)
 
@@ -106,6 +114,9 @@
 		else // Inserting the needle
 			if(!L.can_inject(user, TRUE))
 				return
+			if(HAS_TRAIT(target, TRAIT_HAS_IV_BAG))
+				to_chat(user, "<span class='warning'>[target] already [target.p_have()] another IV bag inserted into [target.p_them()]!</span>")
+				return
 			if(amount_per_transfer_from_this > 10) // We only want to be able to transfer 1, 5, or 10 units to people. Higher numbers are for transfering to other containers
 				to_chat(user, "<span class='warning'>The IV bag can only be used on someone with a transfer amount of 1, 5 or 10.</span>")
 				return