lots of things

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

@@ -0,0 +1,63 @@
+package chess.io.commands;
+
+import chess.io.Command;
+import chess.io.CommandResult;
+import chess.io.OutputSystem;
+import chess.model.ChessBoard;
+import chess.model.Color;
+import chess.model.Game;
+import chess.model.Move;
+import chess.model.Piece;
+import chess.model.visitor.PiecePathChecker;
+
+public class MoveCommand extends Command {
+	private final Move move;
+
+	public MoveCommand(Move move) {
+		this.move = move;
+	}
+
+	@Override
+	public CommandResult execute(Game game, OutputSystem outputSystem) {
+		final ChessBoard board = game.getBoard();
+
+		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;
+
+		board.applyMove(move);
+
+		if (board.isKingInCheck(game.getPlayerTurn())) {
+			board.undoLastMove();
+			return CommandResult.NotAllowed;
+		}
+
+		checkGameStatus(game, outputSystem);
+
+		return CommandResult.Moved;
+	}
+
+	private void checkGameStatus(Game game, OutputSystem outputSystem) {
+		final ChessBoard board = game.getBoard();
+
+		final Color enemy = Color.getEnemy(game.getPlayerTurn());
+
+		if (board.isKingInCheck(enemy)) {
+			if (board.hasAllowedMoves(enemy)) {
+				outputSystem.kingIsInCheck();
+			} else {
+				outputSystem.kingIsInMat();
+				outputSystem.winnerIs(game.getPlayerTurn());
+			}
+		} else if(!board.hasAllowedMoves(enemy)) {
+			outputSystem.patSituation();
+		}
+	}
+}