ports Nebula's ammo magazines lazy-initialize

code/modules/projectiles/ammunition.dm

@@ -17,6 +17,19 @@
 	var/fall_sounds = list('sound/weapons/guns/casingfall1.ogg','sound/weapons/guns/casingfall2.ogg','sound/weapons/guns/casingfall3.ogg')
 
 
+
+/obj/item/ammo_magazine/proc/create_initial_contents()
+	if(contents_initialized || !initial_ammo || !ammo_type)
+		return
+	for(var/i in 1 to initial_ammo)
+		stored_ammo += new ammo_type(src)
+
+/obj/item/ammo_magazine/proc/get_stored_ammo_count()
+	. = length(stored_ammo)
+	if(!contents_initialized)
+		. += initial_ammo
+
+
 /obj/item/ammo_casing/Initialize()
 	if(ispath(projectile_type))
 		BB = new projectile_type(src)
@@ -126,6 +139,11 @@
 	var/list/icon_keys = list()		//keys
 	var/list/ammo_states = list()	//values
 
+	/// Determines whether or not we wait until the first time our contents are gotten to initialize contents. May lead to icon bugs if not handled delicately.
+	var/lazyload_contents = TRUE
+	/// Whether or not our contents have been initialized or not, used in lazyloaded contents.
+	var/contents_initialized = FALSE
+
 
 /obj/item/ammo_magazine/box
 	w_class = ITEM_SIZE_NORMAL
@@ -139,9 +157,8 @@
 	if(isnull(initial_ammo))
 		initial_ammo = max_ammo
 
-	if(initial_ammo)
-		for(var/i in 1 to initial_ammo)
-			stored_ammo += new ammo_type(src)
+	if(!lazyload_contents)
+		create_initial_contents()
 	if(caliber)
 		LAZYINSERT(labels, caliber, 1)
 	if(LAZYLEN(labels))
@@ -155,7 +172,7 @@
 		if(C.caliber != caliber)
 			to_chat(user, SPAN_WARNING("\The [C] does not fit into \the [src]."))
 			return TRUE
-		if(length(stored_ammo) >= max_ammo)
+		if(get_stored_ammo_count() >= max_ammo)
 			to_chat(user, SPAN_WARNING("\The [src] is full!"))
 			return TRUE
 		if(!user.unEquip(C, src))
@@ -168,6 +185,7 @@
 
 
 /obj/item/ammo_magazine/attack_self(mob/user)
+	create_initial_contents()
 	if(!length(stored_ammo))
 		to_chat(user, SPAN_NOTICE("[src] is already empty!"))
 		return
@@ -181,6 +199,7 @@
 
 /obj/item/ammo_magazine/attack_hand(mob/user)
 	if(user.get_inactive_hand() == src)
+		create_initial_contents()
 		if(!length(stored_ammo))
 			to_chat(user, SPAN_NOTICE("[src] is already empty!"))
 		else
@@ -214,19 +233,21 @@
 		icon_state = initial(icon_state)
 
 	if(multiple_sprites)
-		//find the lowest key greater than or equal to length(stored_ammo)
+		//find the lowest key greater than or equal to our ammo count
 		var/new_state = null
+		var/self_ammo_count = get_stored_ammo_count()
 		for(var/idx in 1 to length(icon_keys))
-			var/ammo_count = icon_keys[idx]
-			if (ammo_count >= length(stored_ammo))
+			var/icon_ammo_count = icon_keys[idx]
+			if (icon_ammo_count >= self_ammo_count)
 				new_state = ammo_states[idx]
 				break
 		icon_state = (new_state)? new_state : initial(icon_state)
 
 
 /obj/item/ammo_magazine/examine(mob/user)
 	. = ..()
-	to_chat(user, "There [(length(stored_ammo) == 1)? "is" : "are"] [length(stored_ammo)] round\s left!")
+	var/self_ammo_count = get_stored_ammo_count()
+	to_chat(user, "There [(self_ammo_count == 1)? "is" : "are"] [self_ammo_count] round\s left!")
 
 
 //magazine icon state caching

code/modules/projectiles/ammunition/boxes.dm

@@ -80,6 +80,7 @@
 
 /obj/item/ammo_magazine/shotholder/attack_hand(mob/user)
 	if((user.a_intent == I_HURT) && (length(stored_ammo)))
+		create_initial_contents()
 		var/obj/item/ammo_casing/C = stored_ammo[length(stored_ammo)]
 		stored_ammo-=C
 		user.put_in_hands(C)

code/modules/projectiles/guns/projectile.dm

@@ -73,10 +73,16 @@
 		chambered = loaded[1] //load next casing.
 		if(handle_casings != HOLD_CASINGS)
 			loaded -= chambered
-	else if(ammo_magazine && length(ammo_magazine.stored_ammo))
-		chambered = ammo_magazine.stored_ammo[length(ammo_magazine.stored_ammo)]
-		if(handle_casings != HOLD_CASINGS)
-			ammo_magazine.stored_ammo -= chambered
+	else if(ammo_magazine)
+		if(!ammo_magazine.contents_initialized && ammo_magazine.initial_ammo > 0)
+			chambered = new ammo_magazine.ammo_type(src)
+			if(handle_casings == HOLD_CASINGS)
+				ammo_magazine.stored_ammo += chambered
+			ammo_magazine.initial_ammo--
+		else if(ammo_magazine.stored_ammo.len)
+			chambered = ammo_magazine.stored_ammo[ammo_magazine.stored_ammo.len]
+			if(handle_casings != HOLD_CASINGS)
+				ammo_magazine.stored_ammo -= chambered
 
 	if (chambered)
 		return chambered.BB
@@ -315,7 +321,7 @@
 
 /obj/item/gun/projectile/afterattack(atom/A, mob/living/user)
 	..()
-	if(auto_eject && ammo_magazine && ammo_magazine.stored_ammo && !length(ammo_magazine.stored_ammo))
+	if(auto_eject && ammo_magazine && !ammo_magazine.get_stored_ammo_count())
 		ammo_magazine.dropInto(user.loc)
 		user.visible_message(
 			"[ammo_magazine] falls out and clatters on the floor!",
@@ -342,8 +348,8 @@
 	var/bullets = 0
 	if(loaded)
 		bullets += length(loaded)
-	if(ammo_magazine && ammo_magazine.stored_ammo)
-		bullets += length(ammo_magazine.stored_ammo)
+	if(ammo_magazine)
+		bullets += ammo_magazine.get_stored_ammo_count()
 	if(chambered)
 		bullets += 1
 	return bullets

code/modules/projectiles/guns/projectile/automatic.dm

@@ -246,7 +246,7 @@
 /obj/item/gun/projectile/automatic/bullpup_rifle/on_update_icon()
 	..()
 	if(ammo_magazine)
-		if(length(ammo_magazine.stored_ammo))
+		if(length(ammo_magazine.get_stored_ammo_count()))
 			icon_state = "carbine-loaded"
 		else
 			icon_state = "carbine-empty"
@@ -351,7 +351,7 @@
 /obj/item/gun/projectile/automatic/l6_saw/on_update_icon()
 	..()
 	if(istype(ammo_magazine, /obj/item/ammo_magazine/box))
-		icon_state = "l6[cover_open ? "open" : "closed"][round(length(ammo_magazine.stored_ammo), 10)]"
+		icon_state = "l6[cover_open ? "open" : "closed"][round(length(ammo_magazine.get_stored_ammo_count()), 10)]"
 		item_state = "l6[cover_open ? "open" : "closed"]"
 		wielded_item_state = "l6[cover_open ? "open" : "closed"]-wielded"
 	else if(ammo_magazine)

code/modules/projectiles/guns/projectile/dartgun.dm

@@ -81,12 +81,12 @@
 		icon_state = "dartgun-empty"
 		return 1
 
-	if(!ammo_magazine.stored_ammo || length(ammo_magazine.stored_ammo))
+	if(!ammo_magazine.get_stored_ammo_count() || length(ammo_magazine.get_stored_ammo_count()))
 		icon_state = "dartgun-0"
-	else if(length(ammo_magazine.stored_ammo) > 5)
+	else if(length(ammo_magazine.get_stored_ammo_count()) > 5)
 		icon_state = "dartgun-5"
 	else
-		icon_state = "dartgun-[length(ammo_magazine.stored_ammo)]"
+		icon_state = "dartgun-[length(ammo_magazine.get_stored_ammo_count())]"
 	return 1
 
 /obj/item/gun/projectile/dartgun/consume_next_projectile()
@@ -166,8 +166,8 @@
 			dat += " \[<A href='?src=\ref[src];eject=[i]'>Eject</A>\]<br>"
 
 	if(ammo_magazine)
-		if(ammo_magazine.stored_ammo && length(ammo_magazine.stored_ammo))
-			dat += "The dart cartridge has [length(ammo_magazine.stored_ammo)] shots remaining."
+		if(ammo_magazine.stored_ammo && length(ammo_magazine.get_stored_ammo_count()))
+			dat += "The dart cartridge has [length(ammo_magazine.get_stored_ammo_count())] shots remaining."
 		else
 			dat += SPAN_COLOR("red", "The dart cartridge is empty!")
 		dat += " \[<A href='?src=\ref[src];eject_cart=1'>Eject</A>\]<br>"