Graceful shutdown of network sockets

client/src/main/scala/hexacraft/client/GameClient.scala

@@ -41,22 +41,13 @@ object GameClient {
   ): Result[(GameClient, Channel.Receiver[GameClient.Event]), String] = {
     val socket = GameClientSocket(serverIp, serverPort)
 
-    val loginResponse = socket.sendPacketAndWait(NetworkPacket.Login(playerId, "Some name")).asMap.get
-    val loginSuccessful = loginResponse.getBoolean("success", false)
-    if !loginSuccessful then {
-      val errorMessage = loginResponse.getString("error", "")
-      return Result.Err(s"failed to login: $errorMessage")
+    val (worldInfo, player) = fetchWorldInfo(socket, playerId) match {
+      case Result.Ok(value) => value
+      case Result.Err(message) =>
+        socket.close()
+        return Result.Err(s"failed to connect to server: $message")
     }
 
-    val worldInfo = WorldInfo.fromNBT(
-      socket.sendPacketAndWait(NetworkPacket.GetWorldInfo).asInstanceOf[Nbt.MapTag],
-      null,
-      WorldSettings.none
-    )
-
-    val playerNbt = socket.sendPacketAndWait(NetworkPacket.GetPlayerState)
-    val player = Player.fromNBT(playerId, playerNbt.asInstanceOf[Nbt.MapTag])
-
     val blockSpecs = BlockSpecs.default
     val blockTextureMapping = loadBlockTextures(blockSpecs, blockLoader)
     val blockTextureIndices: Map[String, IndexedSeq[Int]] =
@@ -133,6 +124,29 @@ object GameClient {
     Result.Ok((client, rx))
   }
 
+  private def fetchWorldInfo(socket: GameClientSocket, playerId: UUID): Result[(WorldInfo, Player), String] = try {
+    val loginResponse = socket.sendPacketAndWait(NetworkPacket.Login(playerId, "Some name")).asMap.get
+    val loginSuccessful = loginResponse.getBoolean("success", false)
+    if !loginSuccessful then {
+      val errorMessage = loginResponse.getString("error", "")
+      return Result.Err(s"failed to login: $errorMessage")
+    }
+
+    val worldInfo = WorldInfo.fromNBT(
+      socket.sendPacketAndWait(NetworkPacket.GetWorldInfo).asMap.get,
+      null,
+      WorldSettings.none
+    )
+
+    val playerNbt = socket.sendPacketAndWait(NetworkPacket.GetPlayerState)
+    val player = Player.fromNBT(playerId, playerNbt.asMap.get)
+
+    Result.Ok((worldInfo, player))
+  } catch {
+    case e: Exception =>
+      Result.Err(e.getMessage)
+  }
+
   private def calculateTextureColor(texture: PixelArray): Vector3f = {
     var r = 0L
     var g = 0L
@@ -918,5 +932,9 @@ class GameClientSocket(serverIp: String, serverPort: Int) {
     context.synchronized {
       context.close()
     }
+
+    if monitoringThread != null then {
+      monitoringThread.interrupt()
+    }
   }
 }

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

@@ -9,7 +9,6 @@ import hexacraft.main.GameScene.Event.{CursorCaptured, CursorReleased, GameQuit}
 import hexacraft.server.GameServer
 import hexacraft.util.{Channel, Result}
 import hexacraft.world.WorldProvider
-import hexacraft.world.block.BlockSpec
 
 import java.util.UUID
 
@@ -50,8 +49,12 @@ object GameScene {
       c.initialWindowSize,
       c.audioSystem
     ) match {
-      case Result.Ok(res)      => res
-      case Result.Err(message) => return Result.Err(s"failed to start game: $message")
+      case Result.Ok(res) => res
+      case Result.Err(message) =>
+        if server.isDefined then {
+          server.get.unload()
+        }
+        return Result.Err(s"failed to start game: $message")
     }
 
     clientEvents.onEvent {

server/src/test/scala/hexacraft/world/ServerWorldTest.scala

@@ -127,6 +127,8 @@ class ServerWorldTest extends FunSuite {
     Thread.sleep(20)
     world.tick(Seq(camera), Seq(), Seq())
 
+    assert(world.getChunk(ChunkRelWorld(0, 0, 0)).isDefined)
+
     val entity = Entity(
       UUID.randomUUID(),
       "scorpion",