change project structure

app/src/main/java/chess/controller/commands/MoveCommand.java

@@ -0,0 +1,80 @@
+package chess.controller.commands;
+
+import chess.controller.OutputSystem;
+import chess.controller.PlayerCommand;
+import chess.model.ChessBoard;
+import chess.model.Coordinate;
+import chess.model.Game;
+import chess.model.Move;
+import chess.model.Piece;
+import chess.model.visitor.PiecePathChecker;
+
+public class MoveCommand extends PlayerCommand {
+	
+	private final Move move;
+	private Piece deadPiece;
+
+	public MoveCommand(Move move) {
+		this.move = move;
+		this.deadPiece = null;
+	}
+
+	public Move getMove() {
+		return move;
+	}
+
+	@Override
+	public CommandResult execute(Game game, OutputSystem outputSystem) {
+		final ChessBoard board = game.getBoard();
+
+		// we must promote the pending pawn before
+		if (game.pawnShouldBePromoted())
+			return CommandResult.NotAllowed;
+
+		Piece piece = board.pieceAt(move.getStart());
+		if (piece == null)
+			return CommandResult.NotAllowed;
+
+		if (piece.getColor() != game.getPlayerTurn())
+			return CommandResult.NotAllowed;
+
+		boolean valid = new PiecePathChecker(board, move).isValid();
+		if (!valid)
+			return CommandResult.NotAllowed;
+
+		this.deadPiece = board.pieceAt(move.getFinish());
+		board.applyMove(move);
+
+		if (board.isKingInCheck(game.getPlayerTurn())) {
+			board.undoLastMove();
+			return CommandResult.NotAllowed;
+		}
+
+		if (game.pawnShouldBePromoted()) 
+			return CommandResult.ActionNeeded;
+
+		return CommandResult.Moved;
+	}
+
+	@Override
+	public void undo(Game game, OutputSystem outputSystem) {
+		final ChessBoard board = game.getBoard();
+
+		board.undoMove(move, deadPiece);
+	}
+
+	@Override
+	public void postExec(Game game, OutputSystem outputSystem) {
+		tryPromote(game, outputSystem);
+	}
+
+	private void tryPromote(Game game, OutputSystem outputSystem) {
+		Coordinate pawnPos = game.pawnPromotePosition();
+
+		if (pawnPos == null)
+			return;
+
+		outputSystem.promotePawn(pawnPos);
+	}
+
+}