🕹️ simple gamestate managment

src/main/kotlin/cc/lixou/stracciatella/game/Game.kt

@@ -10,10 +10,11 @@ import java.util.*
 
 abstract class Game {
 
-    protected val players = ArrayList<Player>()
-    protected lateinit var instance: Instance
-    protected val uuid: UUID = UUID.randomUUID()
-    protected val eventNode =
+    val players = ArrayList<Player>()
+    lateinit var instance: Instance
+        protected set
+    val uuid: UUID = UUID.randomUUID()
+    val eventNode =
         EventNode.type("${this.javaClass.simpleName}-${uuid}", EventFilter.INSTANCE) { event, instance ->
             if (event is PlayerEvent) {
                 return@type players.contains(event.player)
@@ -26,6 +27,8 @@ abstract class Game {
         Manager.globalEvent.addChild(eventNode)
     }
 
+    protected fun <T : Enum<*>> initGameState(defaultState: T) = GameState(this, defaultState)
+
     /**
      * @param newPlayers the players that should join
      * @return false if game is full, then creates new instance

src/main/kotlin/cc/lixou/stracciatella/game/GameState.kt

@@ -0,0 +1,44 @@
+package cc.lixou.stracciatella.game
+
+import net.minestom.server.event.EventFilter
+import net.minestom.server.event.EventNode
+import net.minestom.server.event.trait.InstanceEvent
+
+class GameState<T : Enum<*>>(
+    private val game: Game,
+    private val defaultState: T,
+    val parentEventNode: EventNode<*> = game.eventNode
+) {
+
+    private val eventNodes = mutableMapOf<T, EventNode<in InstanceEvent>>()
+
+    var state: T = defaultState
+        set(value) {
+            eventNodes[field]?.let {
+                @Suppress("unchecked_cast")
+                parentEventNode.removeChild(it as EventNode<out Nothing>)
+            }
+            eventNodes[value]?.let {
+                @Suppress("unchecked_cast")
+                parentEventNode.addChild(it as EventNode<out Nothing>)
+            }
+            field = value
+        }
+
+    fun eventNode(ofState: T): EventNode<in InstanceEvent> =
+        eventNodes.getOrPut(ofState) { generateNode(ofState).also { if (state == ofState) register(it) } }
+
+    private fun generateNode(ofState: T): EventNode<in InstanceEvent> =
+        EventNode.type("${game.javaClass.simpleName}-${game.uuid}-${state.name}", EventFilter.INSTANCE) { _, _ ->
+            this@GameState.state == ofState
+        }
+
+    private fun register(node: EventNode<in InstanceEvent>?) {
+        node?.let {
+            @Suppress("unchecked_cast")
+            parentEventNode.addChild(it as EventNode<out Nothing>)
+        }
+    }
+
+
+}