Refactored Inventory into an immutable class

game/src/main/scala/hexacraft/game/GameScene.scala

@@ -143,14 +143,16 @@ class GameScene(
         setUseMouse(false)
         isInPopup = true
 
-        val onCloseInventory = () => {
-          overlays -= inventoryScene
-          inventoryScene.unload()
-          inventoryScene = null
-          isInPopup = false
-          setUseMouse(true)
-        }
-        inventoryScene = InventoryBox(player.inventory, onCloseInventory, blockSpecRegistry)
+        inventoryScene = InventoryBox(player.inventory, blockSpecRegistry):
+          case InventoryBox.Event.BoxClosed =>
+            overlays -= inventoryScene
+            inventoryScene.unload()
+            inventoryScene = null
+            isInPopup = false
+            setUseMouse(true)
+          case InventoryBox.Event.InventoryUpdated(inv) =>
+            player.inventory = inv
+            toolbar.onInventoryUpdated(inv)
 
         overlays += inventoryScene
     case KeyboardKey.Letter('M') =>

game/src/main/scala/hexacraft/game/inventory/InventoryBox.scala

@@ -1,33 +1,30 @@
 package hexacraft.game.inventory
 
+import hexacraft.game
 import hexacraft.gui.{Event, LocationInfo, RenderContext}
 import hexacraft.gui.comp.{Component, GUITransformation}
 import hexacraft.infra.window.{KeyAction, KeyboardKey, MouseAction}
+import hexacraft.util.Tracker
 import hexacraft.world.block.{Block, BlockSpecRegistry}
 import hexacraft.world.player.Inventory
 
 import org.joml.{Matrix4f, Vector4f}
 
 object InventoryBox {
-  def apply(inventory: Inventory, closeScene: () => Unit, specs: BlockSpecRegistry): InventoryBox =
-    val box = new InventoryBox(
-      inventory,
-      closeScene,
-      makeGuiBlockRenderer(specs),
-      makeFloatingBlockRenderer(specs)
-    )
-    box.updateRendererContent()
-    box
+  enum Event:
+    case BoxClosed
+    case InventoryUpdated(inventory: Inventory)
+
+  def apply(currentInventory: Inventory, specs: BlockSpecRegistry)(eventHandler: Tracker[Event]): InventoryBox =
+    val gridRenderer = new GuiBlockRenderer(9, 4)(specs)
+    gridRenderer.setViewMatrix(makeTiltedBlockViewMatrix)
 
-  private def makeGuiBlockRenderer(specs: BlockSpecRegistry) =
-    val renderer = new GuiBlockRenderer(9, 4)(specs)
-    renderer.setViewMatrix(makeTiltedBlockViewMatrix)
-    renderer
+    val floatingBlockRenderer = new GuiBlockRenderer(1, 1)(specs)
+    floatingBlockRenderer.setViewMatrix(makeTiltedBlockViewMatrix)
 
-  private def makeFloatingBlockRenderer(specs: BlockSpecRegistry) =
-    val renderer = GuiBlockRenderer(1, 1)(specs)
-    renderer.setViewMatrix(makeTiltedBlockViewMatrix)
-    renderer
+    val box = new InventoryBox(currentInventory, gridRenderer, floatingBlockRenderer, eventHandler)
+    box.updateRendererContent()
+    box
 
   private def makeTiltedBlockViewMatrix =
     new Matrix4f()
@@ -38,10 +35,10 @@ object InventoryBox {
 }
 
 class InventoryBox private (
-    inventory: Inventory,
-    closeScene: () => Unit,
+    private var inventory: Inventory,
     gridRenderer: GuiBlockRenderer,
-    floatingBlockRenderer: GuiBlockRenderer
+    floatingBlockRenderer: GuiBlockRenderer,
+    eventHandler: Tracker[InventoryBox.Event]
 ) extends Component {
 
   private val location: LocationInfo = LocationInfo(-4.5f * 0.2f, -2.5f * 0.2f, 9 * 0.2f, 4 * 0.2f)
@@ -55,8 +52,6 @@ class InventoryBox private (
   /** The block currently being moved */
   private var floatingBlock: Option[Block] = None
 
-  private val revokeInventoryTracker = inventory.trackChanges(_ => updateRendererContent())
-
   private def updateRendererContent(): Unit =
     gridRenderer.updateContent(-4 * 0.2f, -2 * 0.2f, (0 until 9 * 4).map(i => inventory(i)))
     if floatingBlock.isEmpty then floatingBlockRenderer.updateContent(0, 0, Seq(Block.Air))
@@ -76,13 +71,15 @@ class InventoryBox private (
         key match
           case KeyboardKey.Escape | KeyboardKey.Letter('E') =>
             handleFloatingBlock()
-            closeScene()
+            eventHandler.notify(InventoryBox.Event.BoxClosed)
           case _ =>
       case MouseClickEvent(_, MouseAction.Release, _, mousePos) if location.containsPoint(mousePos) =>
         hoverIndex match
           case Some(hover) =>
             val newFloatingBlock = Some(inventory(hover)).filter(_ != Block.Air)
-            inventory(hover) = floatingBlock.getOrElse(Block.Air)
+            inventory = inventory.updated(hover, floatingBlock.getOrElse(Block.Air))
+            eventHandler.notify(InventoryBox.Event.InventoryUpdated(inventory))
+            updateRendererContent()
             floatingBlock = newFloatingBlock
           case None =>
             handleFloatingBlock()
@@ -93,8 +90,11 @@ class InventoryBox private (
     floatingBlock match
       case Some(block) =>
         inventory.firstEmptySlot match
-          case Some(slot) => inventory(slot) = block
-          case None       => // TODO: drop the block because the inventory is full
+          case Some(slot) =>
+            inventory = inventory.updated(slot, block)
+            eventHandler.notify(InventoryBox.Event.InventoryUpdated(inventory))
+            updateRendererContent()
+          case None => // TODO: drop the block because the inventory is full
       case None =>
 
   override def render(transformation: GUITransformation)(using context: RenderContext): Unit =
@@ -121,7 +121,6 @@ class InventoryBox private (
     then floatingBlockRenderer.render(transformation)
 
   override def unload(): Unit =
-    revokeInventoryTracker()
     gridRenderer.unload()
     floatingBlockRenderer.unload()
     super.unload()

game/src/main/scala/hexacraft/game/inventory/Toolbar.scala

@@ -7,7 +7,7 @@ import hexacraft.world.player.Inventory
 
 import org.joml.{Matrix4f, Vector4f}
 
-class Toolbar(location: LocationInfo, inventory: Inventory)(specs: BlockSpecRegistry)
+class Toolbar(location: LocationInfo, private var inventory: Inventory)(specs: BlockSpecRegistry)
     extends Component
     with SubComponents {
   private val backgroundColor = new Vector4f(0.4f, 0.4f, 0.4f, 0.75f)
@@ -37,7 +37,9 @@ class Toolbar(location: LocationInfo, inventory: Inventory)(specs: BlockSpecRegi
   def setWindowAspectRatio(aspectRatio: Float): Unit =
     guiBlockRenderer.setWindowAspectRatio(aspectRatio)
 
-  private val revokeInventoryTracker = inventory.trackChanges(_ => updateRendererContent())
+  def onInventoryUpdated(inventory: Inventory): Unit =
+    this.inventory = inventory
+    updateRendererContent()
 
   private def updateRendererContent(): Unit =
     guiBlockRenderer.updateContent(-4 * 0.2f, -0.83f, (0 until 9).map(i => inventory(i)))
@@ -56,7 +58,6 @@ class Toolbar(location: LocationInfo, inventory: Inventory)(specs: BlockSpecRegi
   }
 
   override def unload(): Unit = {
-    revokeInventoryTracker()
     guiBlockRenderer.unload()
     super.unload()
   }

game/src/main/scala/hexacraft/world/player/Inventory.scala

@@ -1,45 +1,35 @@
 package hexacraft.world.player
 
-import com.martomate.nbt.Nbt
-import hexacraft.util.{EventDispatcher, RevokeTrackerFn, Tracker}
 import hexacraft.world.block.Block
 
-class Inventory(init_slots: Map[Int, Block]) {
-  private val dispatcher = new EventDispatcher[Unit]
-  def trackChanges(tracker: Tracker[Unit]): RevokeTrackerFn = dispatcher.track(tracker)
-
-  private val slots: Array[Block] = Array.fill(4 * 9)(Block.Air)
-  for ((idx, block) <- init_slots) slots(idx) = block
+import com.martomate.nbt.Nbt
 
-  def apply(idx: Int): Block = slots(idx)
+case class Inventory(slots: Map[Int, Block]) {
+  def apply(idx: Int): Block = slots.getOrElse(idx, Block.Air)
 
   def firstEmptySlot: Option[Int] = (0 until 4 * 9).find(i => this(i) == Block.Air)
 
-  def update(idx: Int, block: Block): Unit =
-    slots(idx) = block
-    dispatcher.notify(())
+  def updated(idx: Int, block: Block): Inventory = Inventory(slots.updated(idx, block))
 
   def toNBT: Nbt.MapTag =
     Nbt.makeMap(
       "slots" ->
         Nbt
           .ListTag(
-            slots.toSeq.zipWithIndex
-              .filter((block, _) => block.id != Block.Air.id)
-              .map((block, idx) => Nbt.makeMap("slot" -> Nbt.ByteTag(idx.toByte), "id" -> Nbt.ByteTag(block.id)))
+            for
+              (idx, block) <- slots.toSeq
+              if block != Block.Air
+            yield Nbt.makeMap(
+              "slot" -> Nbt.ByteTag(idx.toByte),
+              "id" -> Nbt.ByteTag(block.id)
+            )
           )
     )
-
-  override def equals(obj: Any): Boolean =
-    obj match
-      case inv: Inventory =>
-        inv.slots.sameElements(this.slots)
-      case _ => false
 }
 
 object Inventory {
   def default: Inventory =
-    new Inventory(
+    Inventory(
       Map(
         0 -> Block.Dirt,
         1 -> Block.Grass,
@@ -68,6 +58,6 @@ object Inventory {
             else None
           case _ => None
         }
-        new Inventory(Map.from(slots))
-      case None => new Inventory(Map.empty)
+        Inventory(Map.from(slots))
+      case None => Inventory(Map.empty)
 }

game/src/main/scala/hexacraft/world/player/Player.scala

@@ -6,7 +6,7 @@ import hexacraft.world.coord.fp.CylCoords
 import com.martomate.nbt.Nbt
 import org.joml.Vector3d
 
-class Player(val inventory: Inventory) {
+class Player(var inventory: Inventory) {
   val bounds = new HexBox(0.2f, -1.65f, 0.1f)
   val velocity = new Vector3d
   val position = new Vector3d

game/src/test/scala/hexacraft/world/player/PlayerTest.scala

@@ -30,7 +30,7 @@ class PlayerTest extends FunSuite {
     playerBefore.rotation.set(0.1, 0.2, -0.3)
     playerBefore.flying = true
     playerBefore.selectedItemSlot = 7
-    playerBefore.inventory(3) = Block.Stone
+    playerBefore.inventory = playerBefore.inventory.updated(3, Block.Stone)
 
     val playerAfter = Player.fromNBT(playerBefore.toNBT)