Optimizes customizable foods slightly + makes stacking beyond the limit of 41 impossible to avoid the server from dying (#16108)

* Optimizes customizable snacks + fixes exploit
Makes adding ingredients to customizable snacks less performance heavy.
Makes it impossible to add customizable snacks together if that would make it go over the ingredient limit

* Fixes the auto doc syntax used

* QOL put in active hand + bug fix

code/modules/food_and_drinks/food/customizables.dm

@@ -1,43 +1,43 @@
+#define MAKE_CUSTOM_FOOD(snack_to_add, user, type) \
+do {\
+	var/obj/item/reagent_containers/food/snacks/customizable/custom_snack = new type(get_turf(user));\
+	custom_snack.add_ingredient(snack_to_add, user); \
+	user.put_in_active_hand(custom_snack); \
+	qdel(src);\
+} while(FALSE)
+
 /obj/item/reagent_containers/food/snacks/breadslice/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/reagent_containers/food/snacks) && !(W.flags & NODROP))
-		var/obj/item/reagent_containers/food/snacks/customizable/sandwich/S = new(get_turf(user))
-		S.attackby(W,user, params)
-		qdel(src)
+		MAKE_CUSTOM_FOOD(W, user, /obj/item/reagent_containers/food/snacks/customizable/sandwich)
 	else
 		..()
 
 /obj/item/reagent_containers/food/snacks/bun/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/reagent_containers/food/snacks) && !(W.flags & NODROP))
-		var/obj/item/reagent_containers/food/snacks/customizable/burger/S = new(get_turf(user))
-		S.attackby(W,user, params)
-		qdel(src)
+		MAKE_CUSTOM_FOOD(W, user, /obj/item/reagent_containers/food/snacks/customizable/burger)
 
 /obj/item/reagent_containers/food/snacks/sliceable/flatdough/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/reagent_containers/food/snacks) && !(W.flags & NODROP))
-		var/obj/item/reagent_containers/food/snacks/customizable/pizza/S = new(get_turf(user))
-		S.attackby(W,user, params)
-		qdel(src)
+		MAKE_CUSTOM_FOOD(W, user, /obj/item/reagent_containers/food/snacks/customizable/pizza)
 	else
 		..()
 
 
 /obj/item/reagent_containers/food/snacks/boiledspaghetti/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/reagent_containers/food/snacks) && !(W.flags & NODROP))
-		var/obj/item/reagent_containers/food/snacks/customizable/pasta/S = new(get_turf(user))
-		S.attackby(W,user, params)
-		qdel(src)
+		MAKE_CUSTOM_FOOD(W, user, /obj/item/reagent_containers/food/snacks/customizable/pasta)
 	else
 		..()
 
 
 /obj/item/trash/plate/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/reagent_containers/food/snacks) && !(W.flags & NODROP))
-		var/obj/item/reagent_containers/food/snacks/customizable/fullycustom/S = new(get_turf(user))
-		S.attackby(W,user, params)
-		qdel(src)
+		MAKE_CUSTOM_FOOD(W, user, /obj/item/reagent_containers/food/snacks/customizable/fullycustom)
 	else
 		..()
 
+#undef MAKE_CUSTOM_FOOD
+
 /obj/item/trash/bowl
 	name = "bowl"
 	desc = "An empty bowl. Put some food in it to start making a soup."
@@ -58,7 +58,6 @@
 	icon_state = "breadslice"
 	baseicon = "sandwichcustom"
 	basename = "sandwich"
-	toptype = new /obj/item/reagent_containers/food/snacks/breadslice()
 
 
 
@@ -70,16 +69,24 @@
 	var/baseicon = "sandwichcustom"
 	var/basename = "sandwichcustom"
 	bitesize = 4
-	var/top = 1	//Do we have a top?
-	var/obj/item/toptype
+	/// Do we have a top?
+	var/top = TRUE
+	/// The image of the top
+	var/image/top_image
 	var/snack_overlays = 1	//Do we stack?
 //	var/offsetstuff = 1 //Do we offset the overlays?
-	var/sandwich_limit = 40
+	var/ingredient_limit = 40
 	var/fullycustom = 0
 	trash = /obj/item/trash/plate
 	var/list/ingredients = list()
 	list_reagents = list("nutriment" = 8)
 
+/obj/item/reagent_containers/food/snacks/customizable/Initialize(mapload)
+	. = ..()
+	if(top)
+		top_image = new(icon, "[baseicon]_top")
+		add_overlay(top_image)
+
 /obj/item/reagent_containers/food/snacks/customizable/pizza
 	name = "personal pizza"
 	desc = "A personalized pan pizza meant for only one person."
@@ -303,7 +310,7 @@
 	basename = "on a plate"
 	snack_overlays = 0
 	top = 0
-	sandwich_limit = 20
+	ingredient_limit = 20
 	fullycustom = 1
 
 /obj/item/reagent_containers/food/snacks/customizable/soup
@@ -321,71 +328,102 @@
 /obj/item/reagent_containers/food/snacks/customizable/burger
 	name = "burger bun"
 	desc = "A bun for a burger. Delicious."
-	icon_state = "burger"
+	icon_state = "burgercustom"
 	baseicon = "burgercustom"
 	basename = "burger"
-	toptype = new /obj/item/reagent_containers/food/snacks/bun()
 	tastes = list("bun" = 4)
 
+
 /obj/item/reagent_containers/food/snacks/customizable/attackby(obj/item/I, mob/user, params)
-	if(contents.len > sandwich_limit)
+	if(!istype(I, /obj/item/reagent_containers/food/snacks))
+		to_chat(user, "<span class='warning'>[I] isn't exactly something that you would want to eat.</span>")
+		return
+
+	add_ingredient(I, user)
+
+/**
+ * Tries to add one ingredient and it's ingredients, if any and applicable, to this snack
+ *
+ * Arguments:
+ * * snack - The ingredient that will be added
+ */
+/obj/item/reagent_containers/food/snacks/customizable/proc/add_ingredient(obj/item/reagent_containers/food/snacks/snack, mob/user)
+	if(length(ingredients) > ingredient_limit)
 		to_chat(user, "<span class='warning'>If you put anything else in or on [src] it's going to make a mess.</span>")
 		return
-	if(!istype(I, /obj/item/reagent_containers/food/snacks))
-		to_chat(user, "\The [I] isn't exactly something that you would want to eat.")
+
+	// Fully custom snacks don't add the ingredients. So no need to check
+	if(!fullycustom && istype(snack, /obj/item/reagent_containers/food/snacks/customizable))
+		var/obj/item/reagent_containers/food/snacks/customizable/origin = snack
+		if(length(ingredients) + length(origin.ingredients) > ingredient_limit)
+			to_chat(user, "<span class='warning'>Merging [snack] and [src] together is going to make a mess.</span>")
+			return
+
+	if(!user.unEquip(snack))
+		to_chat(user, "<span class='warning'>[snack] is stuck to your hand!</span>")
 		return
-	to_chat(user, "<span class='notice'>You add [I] to [src].</span>")
-	if(istype(I,  /obj/item/reagent_containers/))
-		var/obj/item/reagent_containers/F = I
-		F.reagents.trans_to(src, F.reagents.total_volume)
-	if(istype(I, /obj/item/reagent_containers/food/snacks/customizable))
-		var/obj/item/reagent_containers/food/snacks/customizable/origin = I
-		ingredients += origin.ingredients
-	user.drop_item()
-	cooktype[basename] = 1
-	I.loc = src
-	if(!istype(I, toptype))
-		ingredients += I
-	updateicon()
+
+	to_chat(user, "<span class='notice'>You add [snack] to [src].</span>")
+	snack.reagents.trans_to(src, snack.reagents.total_volume)
+
+	var/list/added_ingredients = list(snack)
+
+	// Only merge when it is not fullycustom. Else it looks weird
+	if(!fullycustom && istype(snack, /obj/item/reagent_containers/food/snacks/customizable))
+		var/obj/item/reagent_containers/food/snacks/customizable/origin = snack
+		added_ingredients += origin.ingredients
+		origin.ingredients.Cut()
+		origin.name = initial(origin.name) // Reset the name for the examine text
+
+	cooktype[basename] = TRUE
+	snack.forceMove(src)
+	add_ingredients(added_ingredients)
+
 	name = newname()
 
+/**
+ * Adds a list of ingredients to the existing snack. Updates the overlays as well
+ *
+ * Arguments:
+ * * new_ingredients - The new ingredients to be added
+ */
+/obj/item/reagent_containers/food/snacks/customizable/proc/add_ingredients(list/new_ingredients)
+	cut_overlay(top_image) // Remove the top image so we can change it again
 
-/obj/item/reagent_containers/food/snacks/customizable/proc/updateicon()
-	overlays = 0
-	var/i=0
-	for(var/obj/item/O in ingredients)
-		i++
+	var/ingredient_num = length(ingredients)
+	ingredients += new_ingredients
+	for(var/obj/item/reagent_containers/food/snacks/food as anything in new_ingredients)
+		ingredient_num++
+		var/image/ingredient_image
 		if(!fullycustom)
-			var/image/I = new(icon, "[baseicon]_filling")
-			if(istype(O, /obj/item/reagent_containers/food/snacks))
-				var/obj/item/reagent_containers/food/snacks/food = O
-				if(!food.filling_color == "#FFFFFF")
-					I.color = food.filling_color
-				else
-					I.color = pick("#FF0000","#0000FF","#008000","#FFFF00")
+			ingredient_image = new(icon, "[baseicon]_filling")
+			if(!food.filling_color == "#FFFFFF")
+				ingredient_image.color = food.filling_color
 			else
-				I.color = pick("#FF0000","#0000FF","#008000","#FFFF00")
+				ingredient_image.color = pick("#FF0000", "#0000FF", "#008000", "#FFFF00")
 			if(snack_overlays)
-				I.pixel_x = pick(list(-1,0,1))
-				I.pixel_y = (i*2)+1
-			overlays += I
+				ingredient_image.pixel_x = rand(2) - 1
+				ingredient_image.pixel_y = ingredient_num * 2 + 1
 		else
-			var/image/F = new(O.icon, O.icon_state)
-			F.pixel_x = pick(list(-1,0,1))
-			F.pixel_y = pick(list(-1,0,1))
-			overlays += F
-			overlays += O.overlays
+			ingredient_image = new(food.icon, food.icon_state)
+			ingredient_image.pixel_x = rand(2) - 1
+			ingredient_image.pixel_y = rand(2) - 1
+			add_overlay(food.overlays)
+
+		add_overlay(ingredient_image)
+
+	if(top_image)
+		top_image.pixel_x = rand(2) - 1
+		top_image.pixel_y = ingredient_num * 2 + 1
+		add_overlay(top_image)
 
-	if(top)
-		var/image/T = new(icon, "[baseicon]_top")
-		T.pixel_x = pick(list(-1,0,1))
-		T.pixel_y = (ingredients.len * 2)+1
-		overlays += T
 
 /obj/item/reagent_containers/food/snacks/customizable/Destroy()
 	QDEL_LIST(ingredients)
+	qdel(top_image)
 	return ..()
 
+
 /obj/item/reagent_containers/food/snacks/customizable/examine(mob/user)
 	. = ..()
 	if(LAZYLEN(ingredients))