package chess.model;

import chess.model.pieces.Pawn;

public class Game {
	private final ChessBoard board;
	private Color playerTurn;

	public enum GameStatus {
		Check, CheckMate, OnGoing, Pat;
	}

	public Game(ChessBoard board) {
		this.board = board;
	}

	public ChessBoard getBoard() {
		return board;
	}

	public Color getPlayerTurn() {
		return playerTurn;
	}

	public void resetPlayerTurn() {
		this.playerTurn = Color.White;
	}

	public void switchPlayerTurn() {
		playerTurn = Color.getEnemy(playerTurn);
	}

	public GameStatus checkGameStatus() {
		final Color enemy = Color.getEnemy(getPlayerTurn());

		if (this.board.isKingInCheck(enemy))
			if (this.board.hasAllowedMoves(enemy))
				return GameStatus.Check;
			else
				return GameStatus.CheckMate;

		if (!board.hasAllowedMoves(enemy))
			return GameStatus.Pat;

		return GameStatus.OnGoing;
	}

	public boolean pawnShouldBePromoted() {
		return pawnPromotePosition() != null;
	}

	/**
	 * 
	 * @return Null if there is no pawn to promote
	 */
	public Coordinate pawnPromotePosition() {
		Coordinate piecePos = pawnPromotePosition(Color.White);
		if (piecePos != null)
			return piecePos;
		return pawnPromotePosition(Color.Black);
	}

	/**
	 * 
	 * @return Null if there is no pawn to promote
	 */
	private Coordinate pawnPromotePosition(Color color) {
		int enemyLineY = color == Color.White ? 0 : 7;

		for (int x = 0; x < Coordinate.VALUE_MAX; x++) {
			Coordinate pieceCoords = new Coordinate(x, enemyLineY);
			Piece piece = getBoard().pieceAt(pieceCoords);

			if (piece == null || !(piece instanceof Pawn) || piece.getColor() != color)
				continue;

			return pieceCoords;
		}

		return null;
	}

}