Basic ship spawning queue (#2578)

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## About The Pull Request

Not even a queue really. Basically it just prevents people from spawning
a ship while a ship is already spawning.

## Why It's Good For The Game

Multiple ships spawning is a recipe for disaster and lag.

## Changelog

:cl:
fix: Only one ship can spawn at a time.
/:cl:

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code/controllers/subsystem/overmap.dm

@@ -31,6 +31,9 @@ SUBSYSTEM_DEF(overmap)
 	///The two-dimensional list that contains every single tile in the overmap as a sublist.
 	var/list/list/overmap_container
 
+	///Whether or not a ship is currently being spawned. Used to prevent multiple ships from being spawned at once.
+	var/ship_spawning //TODO: Make a proper queue for this
+
 /datum/controller/subsystem/overmap/get_metrics()
 	. = ..()
 	var/list/cust = list()
@@ -227,13 +230,18 @@ SUBSYSTEM_DEF(overmap)
  * Inteded for ship purchases, etc.
  */
 /datum/controller/subsystem/overmap/proc/spawn_ship_at_start(datum/map_template/shuttle/template)
+	//Should never happen, but just in case. This'll delay the next spawn until the current one is done.
+	UNTIL(!ship_spawning)
+
 	var/ship_loc
 	if(template.space_spawn)
 		ship_loc = null
 	else
 		ship_loc = SSovermap.outposts[1]
 
-	return new /datum/overmap/ship/controlled(ship_loc, template)
+	ship_spawning = TRUE
+	. = new /datum/overmap/ship/controlled(ship_loc, template) //This statement SHOULDN'T runtime (not counting runtimes actually in the constructor) so ship_spawning should always be toggled.
+	ship_spawning = FALSE
 
 /**
  * Creates an overmap object for each ruin level, making them accessible.

code/modules/mob/dead/new_player/ship_select.dm

@@ -71,6 +71,9 @@
 				return
 
 			var/datum/map_template/shuttle/template = SSmapping.ship_purchase_list[params["name"]]
+			if(SSovermap.ship_spawning)
+				to_chat(spawnee, "<span class='danger'>A ship is currently spawning. Try again in a little while.</span>")
+				return
 			if(!SSovermap.player_ship_spawn_allowed())
 				to_chat(spawnee, "<span class='danger'>No more ships may be spawned at this time!</span>")
 				return
@@ -104,6 +107,10 @@
 				to_chat(spawnee, "<span class='danger'>Ship spawned, but you were unable to be spawned. You can likely try to spawn in the ship through joining normally, but if not, please contact an admin.</span>")
 				spawnee.new_player_panel()
 
+/datum/ship_select/ui_data(mob/user)
+	. = list()
+	.["shipSpawning"] = SSovermap.ship_spawning
+
 /datum/ship_select/ui_static_data(mob/user)
 	// tracks the number of existing ships of each template type so that their unavailability for purchase can be communicated to the user
 	var/list/template_num_lookup = list()

tgui/packages/tgui/interfaces/ShipSelect.js

@@ -67,7 +67,9 @@ export const ShipSelect = (props, context) => {
                     (data.purchaseBanned &&
                       'You are banned from purchasing ships.') ||
                     (!data.shipSpawnAllowed &&
-                      'No more ships may be spawned at this time.')
+                      'No more ships may be spawned at this time.') ||
+                    (data.shipSpawning &&
+                      'A ship is currently spawning. Please wait.')
                   }
                   disabled={data.purchaseBanned}
                   onClick={() => {
@@ -254,10 +256,13 @@ export const ShipSelect = (props, context) => {
                         'There are too many ships of this type.') ||
                       (!data.autoMeet &&
                         data.playMin < template.minTime &&
-                        'You do not have enough playtime to buy this ship.')
+                        'You do not have enough playtime to buy this ship.') ||
+                      (data.shipSpawning &&
+                        'A ship is currently spawning. Please wait.')
                     }
                     disabled={
                       !data.shipSpawnAllowed ||
+                      data.shipSpawning ||
                       template.curNum >= template.limit ||
                       (!data.autoMeet && data.playMin < template.minTime)
                     }