package dev.kske.chess.board;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.Objects;

import dev.kske.chess.board.Piece.Color;

/**
 * Project: <strong>Chess</strong><br>
 * File: <strong>PawnPromotion.java</strong><br>
 * Created: <strong>2 Nov 2019</strong><br>
 *
 * @since Chess v0.5-alpha
 * @author Kai S. K. Engelbart
 */
public class PawnPromotion extends Move {

	private final Constructor<? extends Piece> promotionPieceConstructor;
	private final char promotionPieceChar;

	/**
	 * Initializes a pawn promotion move.
	 *
	 * @param pos                 the position of this move
	 * @param dest                the destination of this move
	 * @param promotionPieceClass the class of the piece to which the pawn is
	 *                            promoted
	 * @throws ReflectiveOperationException if the promotion piece could not be
	 *                                      instantiated
	 * @throws RuntimeException             if the promotion piece could not be
	 *                                      instantiated
	 */
	public PawnPromotion(
		Position pos, Position dest, Class<? extends Piece> promotionPieceClass
	)
		throws ReflectiveOperationException, RuntimeException {
		super(pos, dest);

		// Cache piece constructor
		promotionPieceConstructor = promotionPieceClass
			.getDeclaredConstructor(Color.class, Board.class);
		promotionPieceConstructor.setAccessible(true);

		// Get piece char
		promotionPieceChar = (char) promotionPieceClass.getMethod("firstChar")
			.invoke(promotionPieceConstructor.newInstance(null, null));
	}

	/**
	 * Creates an instance of {@link PawnPromotion}.
	 *
	 * @param xPos                the horizontal position of this move
	 * @param yPos                the vertical position of this move
	 * @param xDest               the horizontal destination of this move
	 * @param yDest               the vertical destination of this move
	 * @param promotionPieceClass the class of the piece to which the pawn is
	 *                            promoted
	 * @throws ReflectiveOperationException if the promotion piece could not be
	 *                                      instantiated
	 * @throws RuntimeException             if the promotion piece could not be
	 *                                      instantiated
	 */
	public PawnPromotion(
		int xPos, int yPos, int xDest, int yDest,
		Class<? extends Piece> promotionPieceClass
	)
		throws ReflectiveOperationException, RuntimeException {
		this(
			new Position(xPos, yPos),
			new Position(xDest, yDest),
			promotionPieceClass
		);
	}

	@Override
	public void execute(Board board) {
		try {
			board.set(
				pos,
				promotionPieceConstructor.newInstance(board.get(pos).getColor(), board)
			);
			super.execute(board);
		} catch (
			InstantiationException
			| IllegalAccessException
			| IllegalArgumentException
			| InvocationTargetException
			| SecurityException e
		) {
			e.printStackTrace();
		}
	}

	@Override
	public void revert(Board board, Piece capturedPiece) {
		board.set(dest, new Pawn(board.get(dest).getColor(), board));
		super.revert(board, capturedPiece);
	}

	@Override
	public String toLAN() {
		return pos.toLAN() + dest.toLAN() + promotionPieceChar;
	}

	@Override
	public String toSAN(Board board) {
		String san = super.toSAN(board);
		return san + Character.toUpperCase(promotionPieceChar);
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = super.hashCode();
		result = prime * result
			+ Objects.hash(promotionPieceChar, promotionPieceConstructor);
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (!super.equals(obj))
			return false;
		if (!(obj instanceof PawnPromotion))
			return false;
		PawnPromotion other = (PawnPromotion) obj;
		return promotionPieceChar == other.promotionPieceChar && Objects
			.equals(promotionPieceConstructor, other.promotionPieceConstructor);
	}
}