refactor: clean up code formatting and improve readability in ChessBoardView and related files

modules/io/src/main/scala/de/nowchess/io/GameFileService.scala

@@ -7,8 +7,7 @@ import scala.util.Try
 
 /** Service for persisting and loading game states to/from disk.
   *
- *  Abstracts file I/O operations away from the UI layer.
+  * Abstracts file I/O operations away from the UI layer. Handles both reading and writing game files.
- *  Handles both reading and writing game files.
   */
 trait GameFileService:
   def saveGameToFile(context: GameContext, path: Path, exporter: GameContextExport): Either[String, Unit]
@@ -25,7 +24,7 @@ object FileSystemGameService extends GameFileService:
       ()
     }.fold(
       ex => Left(s"Failed to save file: ${ex.getMessage}"),
-      _ => Right(())
+      _ => Right(()),
     )
 
   /** Load a game context from a file using the specified importer. */
@@ -35,5 +34,5 @@ object FileSystemGameService extends GameFileService:
       importer.importGameContext(json)
     }.fold(
       ex => Left(s"Failed to load file: ${ex.getMessage}"),
-      result => result
+      result => result,
     )

modules/io/src/main/scala/de/nowchess/io/json/JsonExporter.scala

@@ -8,7 +8,7 @@ import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
 import de.nowchess.api.game.GameContext
 import de.nowchess.io.GameContextExport
 import de.nowchess.io.pgn.PgnExporter
-import java.time.{LocalDate, ZonedDateTime, ZoneId}
+import java.time.{LocalDate, ZoneId, ZonedDateTime}
 
 /** Exports a GameContext to a comprehensive JSON format using Jackson.
   *
@@ -42,9 +42,10 @@ object JsonExporter extends GameContextExport:
     formatJson(mapper.writeValueAsString(record))
 
   private def buildGameRecord(context: GameContext): JsonGameRecord =
-    val pgn = try {
+    val pgn =
+      try
         Some(PgnExporter.exportGameContext(context))
-    } catch {
+      catch {
         case _: Exception => None
       }
     JsonGameRecord(
@@ -53,7 +54,7 @@ object JsonExporter extends GameContextExport:
       moveHistory = pgn,
       moves = Some(buildMoves(context.moves)),
       capturedPieces = Some(buildCapturedPieces(context.board)),
-      timestamp = Some(ZonedDateTime.now(ZoneId.of("UTC")).toString)
+      timestamp = Some(ZonedDateTime.now(ZoneId.of("UTC")).toString),
     )
 
   private def buildMetadata(): JsonMetadata =
@@ -61,7 +62,7 @@ object JsonExporter extends GameContextExport:
       event = Some("Game"),
       players = Some(Map("white" -> "White Player", "black" -> "Black Player")),
       date = Some(LocalDate.now().toString),
-      result = Some("*")
+      result = Some("*"),
     )
 
   private def buildGameState(context: GameContext): JsonGameState =
@@ -70,7 +71,7 @@ object JsonExporter extends GameContextExport:
       turn = Some(context.turn.label),
       castlingRights = Some(buildCastlingRights(context.castlingRights)),
       enPassantSquare = context.enPassantSquare.map(_.toString),
-      halfMoveClock = Some(context.halfMoveClock)
+      halfMoveClock = Some(context.halfMoveClock),
     )
 
   private def buildBoardPieces(board: Board): List[JsonPiece] =
@@ -83,7 +84,7 @@ object JsonExporter extends GameContextExport:
       Some(rights.whiteKingSide),
       Some(rights.whiteQueenSide),
       Some(rights.blackKingSide),
-      Some(rights.blackQueenSide)
+      Some(rights.blackQueenSide),
     )
 
   private def buildMoves(moves: List[Move]): List[JsonMove] =
@@ -136,4 +137,3 @@ object JsonExporter extends GameContextExport:
     val whiteCaptured = captured.filter(_.color == Color.White).map(_.pieceType.label).toList
     val blackCaptured = captured.filter(_.color == Color.Black).map(_.pieceType.label).toList
     (blackCaptured, whiteCaptured)
-

modules/io/src/main/scala/de/nowchess/io/json/JsonModel.scala

@@ -4,20 +4,20 @@ case class JsonMetadata(
     event: Option[String] = None,
     players: Option[Map[String, String]] = None,
     date: Option[String] = None,
-  result: Option[String] = None
+    result: Option[String] = None,
 )
 
 case class JsonPiece(
     square: Option[String] = None,
     color: Option[String] = None,
-  piece: Option[String] = None
+    piece: Option[String] = None,
 )
 
 case class JsonCastlingRights(
     whiteKingSide: Option[Boolean] = None,
     whiteQueenSide: Option[Boolean] = None,
     blackKingSide: Option[Boolean] = None,
-  blackQueenSide: Option[Boolean] = None
+    blackQueenSide: Option[Boolean] = None,
 )
 
 case class JsonGameState(
@@ -25,24 +25,24 @@ case class JsonGameState(
     turn: Option[String] = None,
     castlingRights: Option[JsonCastlingRights] = None,
     enPassantSquare: Option[String] = None,
-  halfMoveClock: Option[Int] = None
+    halfMoveClock: Option[Int] = None,
 )
 
 case class JsonCapturedPieces(
     byWhite: Option[List[String]] = None,
-  byBlack: Option[List[String]] = None
+    byBlack: Option[List[String]] = None,
 )
 
 case class JsonMoveType(
     `type`: Option[String] = None,
     isCapture: Option[Boolean] = None,
-  promotionPiece: Option[String] = None
+    promotionPiece: Option[String] = None,
 )
 
 case class JsonMove(
     from: Option[String] = None,
     to: Option[String] = None,
-  `type`: Option[JsonMoveType] = None
+    `type`: Option[JsonMoveType] = None,
 )
 
 case class JsonGameRecord(
@@ -51,5 +51,5 @@ case class JsonGameRecord(
     moveHistory: Option[String] = None,
     moves: Option[List[JsonMove]] = None,
     capturedPieces: Option[JsonCapturedPieces] = None,
-  timestamp: Option[String] = None
+    timestamp: Option[String] = None,
 )

modules/io/src/main/scala/de/nowchess/io/json/JsonParser.scala

@@ -1,6 +1,6 @@
 package de.nowchess.io.json
 
-import com.fasterxml.jackson.databind.{ObjectMapper, DeserializationFeature}
+import com.fasterxml.jackson.databind.{DeserializationFeature, ObjectMapper}
 import com.fasterxml.jackson.module.scala.DefaultScalaModule
 import de.nowchess.api.board.*
 import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
@@ -27,8 +27,8 @@ object JsonParser extends GameContextImport:
     .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
 
   def importGameContext(input: String): Either[String, GameContext] =
-    Try(mapper.readValue(input, classOf[JsonGameRecord])).toEither
+    Try(mapper.readValue(input, classOf[JsonGameRecord])).toEither.left
-      .left.map(e => "JSON parsing error: " + e.getMessage)
+      .map(e => "JSON parsing error: " + e.getMessage)
       .flatMap { data =>
         val gs       = data.gameState.getOrElse(JsonGameState())
         val rawBoard = gs.board.getOrElse(Nil)
@@ -49,7 +49,7 @@ object JsonParser extends GameContextImport:
           castlingRights = castlingRights,
           enPassantSquare = enPassantSquare,
           halfMoveClock = rawHmc,
-          moves = moves
+          moves = moves,
         )
       }
 
@@ -86,7 +86,7 @@ object JsonParser extends GameContextImport:
       cr.whiteKingSide.getOrElse(false),
       cr.whiteQueenSide.getOrElse(false),
       cr.blackKingSide.getOrElse(false),
-      cr.blackQueenSide.getOrElse(false)
+      cr.blackQueenSide.getOrElse(false),
     )
 
   private def parseMoves(moves: List[JsonMove]): Either[String, List[Move]] =

modules/io/src/test/scala/de/nowchess/io/GameFileServiceSuite.scala

@@ -1,7 +1,7 @@
 package de.nowchess.io
 
 import de.nowchess.api.game.GameContext
-import de.nowchess.api.board.{Square, File, Rank}
+import de.nowchess.api.board.{File, Rank, Square}
 import de.nowchess.api.move.Move
 import de.nowchess.io.json.{JsonExporter, JsonParser}
 import java.nio.file.{Files, Paths}
@@ -20,8 +20,7 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       assert(result.isRight)
       assert(Files.exists(tmpFile))
       assert(Files.size(tmpFile) > 0)
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }
 
   test("loadGameFromFile: reads JSON file successfully") {
@@ -38,8 +37,7 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       assert(result.isRight)
       val loaded = result.getOrElse(GameContext.initial)
       assert(loaded == originalContext)
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }
 
   test("loadGameFromFile: returns error on missing file") {
@@ -65,8 +63,7 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       assert(loadResult.isRight)
       val loaded = loadResult.getOrElse(GameContext.initial)
       assert(loaded.moves.length == 2)
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }
 
   test("saveGameToFile: overwrites existing file") {
@@ -86,8 +83,7 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       assert(loadResult.isRight)
       val loaded = loadResult.getOrElse(GameContext.initial)
       assert(loaded.moves.length == 1)
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }
 
   test("loadGameFromFile: handles invalid JSON in file") {
@@ -97,8 +93,7 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       val result = FileSystemGameService.loadGameFromFile(tmpFile, JsonParser)
 
       assert(result.isLeft)
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }
 
   test("round-trip: save and load preserves game state") {
@@ -118,8 +113,7 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       val loaded = loadResult.getOrElse(GameContext.initial)
       assert(loaded.moves.length == 2)
       assert(loaded.halfMoveClock == 3)
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }
 
   test("saveGameToFile: handles exporter that throws exception") {
@@ -134,6 +128,5 @@ class GameFileServiceSuite extends AnyFunSuite with Matchers:
       val result = FileSystemGameService.saveGameToFile(context, tmpFile, faultyExporter)
       assert(result.isLeft)
       assert(result.left.toOption.get.contains("Failed to save file"))
-    finally
+    finally Files.deleteIfExists(tmpFile)
-      Files.deleteIfExists(tmpFile)
   }

modules/io/src/test/scala/de/nowchess/io/json/JsonExporterBranchCoverageSuite.scala

@@ -1,7 +1,7 @@
 package de.nowchess.io.json
 
 import de.nowchess.api.game.GameContext
-import de.nowchess.api.board.{Square, File, Rank, Board, Color, CastlingRights, Piece, PieceType}
+import de.nowchess.api.board.{Board, CastlingRights, Color, File, Piece, PieceType, Rank, Square}
 import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers
@@ -13,10 +13,10 @@ class JsonExporterBranchCoverageSuite extends AnyFunSuite with Matchers:
       (PromotionPiece.Queen, "queen"),
       (PromotionPiece.Rook, "rook"),
       (PromotionPiece.Bishop, "bishop"),
-      (PromotionPiece.Knight, "knight")
+      (PromotionPiece.Knight, "knight"),
     )
 
-    for ((piece, expectedName) <- promotions) do
+    for (piece, expectedName) <- promotions do
       val move = Move(Square(File.A, Rank.R7), Square(File.A, Rank.R8), MoveType.Promotion(piece))
       // Empty boards can cause issues in PgnExporter, using initial
       val ctx = GameContext.initial.copy(moves = List(move))

modules/io/src/test/scala/de/nowchess/io/json/JsonExporterSuite.scala

@@ -1,7 +1,7 @@
 package de.nowchess.io.json
 
 import de.nowchess.api.game.GameContext
-import de.nowchess.api.board.{Board, Square, Piece, Color, PieceType, File, Rank, CastlingRights}
+import de.nowchess.api.board.{Board, CastlingRights, Color, File, Piece, PieceType, Rank, Square}
 import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers

modules/io/src/test/scala/de/nowchess/io/json/JsonModelExtraTestSuite.scala

@@ -40,7 +40,7 @@ class JsonModelExtraTestSuite extends AnyFunSuite with Matchers:
       Some("White"),
       Some(JsonCastlingRights()),
       Some("e3"),
-      Some(5)
+      Some(5),
     )
     assert(gs.board.contains(Nil))
     assert(gs.halfMoveClock.contains(5))
@@ -88,7 +88,7 @@ class JsonModelExtraTestSuite extends AnyFunSuite with Matchers:
       Some(""),
       Some(Nil),
       Some(JsonCapturedPieces()),
-      Some("2026-04-08T00:00:00Z")
+      Some("2026-04-08T00:00:00Z"),
     )
     assert(record.metadata.nonEmpty)
     assert(record.timestamp.nonEmpty)

modules/io/src/test/scala/de/nowchess/io/json/JsonParserEdgeCasesSuite.scala

@@ -124,7 +124,12 @@ class JsonParserEdgeCasesSuite extends AnyFunSuite with Matchers:
     assert(result.isRight)
     val ctx = result.toOption.get
     assert(ctx.board.pieces.size == 6)
-    assert(ctx.board.pieceAt(de.nowchess.api.board.Square(de.nowchess.api.board.File.A, de.nowchess.api.board.Rank.R1)).get.pieceType == PieceType.Pawn)
+    assert(
+      ctx.board
+        .pieceAt(de.nowchess.api.board.Square(de.nowchess.api.board.File.A, de.nowchess.api.board.Rank.R1))
+        .get
+        .pieceType == PieceType.Pawn,
+    )
   }
 
   test("parse with all castling rights false") {

modules/io/src/test/scala/de/nowchess/io/json/JsonParserMoveTypeSuite.scala

@@ -1,7 +1,7 @@
 package de.nowchess.io.json
 
 import de.nowchess.api.game.GameContext
-import de.nowchess.api.board.{Color, PieceType, Piece, Square, File, Rank}
+import de.nowchess.api.board.{Color, File, Piece, PieceType, Rank, Square}
 import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers

modules/io/src/test/scala/de/nowchess/io/json/JsonParserSuite.scala

@@ -1,7 +1,7 @@
 package de.nowchess.io.json
 
 import de.nowchess.api.game.GameContext
-import de.nowchess.api.board.{Color, File, Rank, Square, CastlingRights}
+import de.nowchess.api.board.{CastlingRights, Color, File, Rank, Square}
 import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers
@@ -68,7 +68,8 @@ class JsonParserSuite extends AnyFunSuite with Matchers:
   }
 
   test("importGameContext: handles missing fields with defaults") {
-    val json = "{\"metadata\": {}, \"gameState\": {\"board\": [], \"turn\": \"White\", \"castlingRights\": {\"whiteKingSide\": true, \"whiteQueenSide\": true, \"blackKingSide\": true, \"blackQueenSide\": true}, \"enPassantSquare\": null, \"halfMoveClock\": 0}, \"moves\": [], \"moveHistory\": \"\", \"capturedPieces\": {\"byWhite\": [], \"byBlack\": []}, \"timestamp\": \"2026-01-01T00:00:00Z\"}"
+    val json =
+      "{\"metadata\": {}, \"gameState\": {\"board\": [], \"turn\": \"White\", \"castlingRights\": {\"whiteKingSide\": true, \"whiteQueenSide\": true, \"blackKingSide\": true, \"blackQueenSide\": true}, \"enPassantSquare\": null, \"halfMoveClock\": 0}, \"moves\": [], \"moveHistory\": \"\", \"capturedPieces\": {\"byWhite\": [], \"byBlack\": []}, \"timestamp\": \"2026-01-01T00:00:00Z\"}"
     val result = JsonParser.importGameContext(json)
 
     assert(result.isRight)

modules/ui/src/main/scala/de/nowchess/ui/gui/ChessBoardView.scala

@@ -17,14 +17,13 @@ import de.nowchess.chess.engine.GameEngine
 import de.nowchess.io.fen.{FenExporter, FenParser}
 import de.nowchess.io.pgn.{PgnExporter, PgnParser}
 import de.nowchess.io.json.{JsonExporter, JsonParser}
-import de.nowchess.io.{GameContextExport, GameContextImport, GameFileService, FileSystemGameService}
+import de.nowchess.io.{FileSystemGameService, GameContextExport, GameContextImport, GameFileService}
 import java.nio.file.Paths
 import scalafx.stage.FileChooser
 import scalafx.stage.FileChooser.ExtensionFilter
 
-/** ScalaFX chess board view that displays the game state.
+/** ScalaFX chess board view that displays the game state. Uses chess sprites and color palette. Handles user
- *  Uses chess sprites and color palette.
+  * interactions (clicks) and sends moves to GameEngine.
- *  Handles user interactions (clicks) and sends moves to GameEngine.
   */
 class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends BorderPane:
 
@@ -58,7 +57,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
         font = Font.font(comicSansFontFamily, 24)
         style = "-fx-font-weight: bold;"
       },
-      messageLabel
+      messageLabel,
     )
   }
 
@@ -86,8 +85,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
               disable = !engine.canUndo
             }
             undoButton
-          },
+          }, {
-          {
             redoButton = new Button("Redo") {
               font = Font.font(comicSansFontFamily, 12)
               onAction = _ => if engine.canRedo then engine.redo()
@@ -100,7 +98,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
             font = Font.font(comicSansFontFamily, 12)
             onAction = _ => engine.reset()
             style = "-fx-background-radius: 8; -fx-background-color: #E1EAA9;"
-          }
+          },
         )
       },
       new HBox {
@@ -126,7 +124,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
             font = Font.font(comicSansFontFamily, 12)
             onAction = _ => doPgnImport()
             style = "-fx-background-radius: 8; -fx-background-color: #B9DAC4;"
-          }
+          },
         )
       },
       new HBox {
@@ -142,9 +140,9 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
             font = Font.font(comicSansFontFamily, 12)
             onAction = _ => doJsonImport()
             style = "-fx-background-radius: 8; -fx-background-color: #C4B9DA;"
-          }
+          },
         )
-      }
+      },
     )
   }
 
@@ -185,8 +183,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
     square
 
   private def handleSquareClick(rank: Int, file: Int): Unit =
-    if engine.isPendingPromotion then
+    if engine.isPendingPromotion then return // Don't allow moves during promotion
-      return // Don't allow moves during promotion
 
     val clickedSquare = Square(File.values(file), Rank.values(rank))
 
@@ -198,7 +195,8 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
             selectedSquare = Some(clickedSquare)
             highlightSquare(rank, file, PieceSprites.SquareColors.Selected)
 
-            val legalDests = engine.ruleSet.legalMoves(engine.context)(clickedSquare)
+            val legalDests = engine.ruleSet
+              .legalMoves(engine.context)(clickedSquare)
               .collect { case move if move.from == clickedSquare => move.to }
             legalDests.foreach { sq =>
               highlightSquare(sq.rank.ordinal, sq.file.ordinal, PieceSprites.SquareColors.ValidMove)
@@ -322,7 +320,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
       val result = FileSystemGameService.saveGameToFile(
         engine.context,
         selectedFile.toPath,
-        JsonExporter
+        JsonExporter,
       )
       result match
         case Right(_)  => showMessage(s"✓ Game saved to: ${selectedFile.getName}")
@@ -339,7 +337,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
     if selectedFile != null then
       val result = FileSystemGameService.loadGameFromFile(
         selectedFile.toPath,
-        JsonParser
+        JsonParser,
       )
       result match
         case Right(gameContext) =>
@@ -353,7 +351,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
     showCopyDialog(s"$formatName Export", exported)
   }
 
-  private def doImport(importer: GameContextImport, formatName: String): Unit = {
+  private def doImport(importer: GameContextImport, formatName: String): Unit =
     showInputDialog(s"$formatName Import", rows = 5).foreach { input =>
       importer.importGameContext(input) match
         case Right(gameContext) =>
@@ -362,7 +360,6 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
         case Left(err) =>
           showMessage(s"⚠️  $formatName Error: $err")
     }
-  }
 
   private def showCopyDialog(title: String, content: String): Unit =
     val area = new javafx.scene.control.TextArea(content)
@@ -386,7 +383,7 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
     dialog.getDialogPane.setContent(area)
     dialog.getDialogPane.getButtonTypes.addAll(
       javafx.scene.control.ButtonType.OK,
-      javafx.scene.control.ButtonType.CANCEL
+      javafx.scene.control.ButtonType.CANCEL,
     )
     dialog.setResultConverter { bt =>
       if bt == javafx.scene.control.ButtonType.OK then area.getText else null
@@ -394,4 +391,3 @@ class ChessBoardView(val stage: Stage, private val engine: GameEngine) extends B
     dialog.initOwner(stage.delegate)
     val result = dialog.showAndWait()
     if result.isPresent && result.get != null && result.get.nonEmpty then Some(result.get) else None
-