OOP_1B6_Project/src/backend/Board.java

346 lines
12 KiB
Java

package backend;
import java.util.ArrayList;
public class Board {
private int selectedX = -1; // negative value means impossible x and y so unselected
private int selectedY = -1;
private int turnNumber = 0; // tracks current turn
private int width; // enables to define the dimensions of board
private int height;
private Piece[][] board; // 2D array chess board
private ArrayList<int[]> highlightedPositions = new ArrayList<>(); // list of valid positions to highlight
public Board(int colNum, int lineNum) {
this.width = colNum;
this.height = lineNum;
this.board = new Piece[width][height]; // first empty board *********REVIEW************
clearConsole();
System.out.println(toString()); // print the chess at the beginning of the game
}
public int getWidth() {
return width;
}
public int getHeight() {
return height;
}
// new piece on the board at x,y (More specifically changes the empty cell of coordinates x,y with a new chess piece)
public void setPiece(boolean isWhite, PieceType type, int x, int y) {
board[x][y] = new Piece(x, y, type, isWhite);
}
public boolean isTurnWhite() {
if (turnNumber % 2 == 0) { // even turns including 0 are white's ones (% calculates the reminder of the euclidean division)
return true;
} else { // same reasoning, odd turns are black's ones
return false;
}
}
public int getTurnNumber() { // this class enables to obtain the current turn number while increment adds 1 to this value for each turn
return turnNumber; // Necessarly in two functions to get rid of an infinite loop ****WHY****
}
public void incrementTurn() {
turnNumber++;
}
// set up the classic chess board taking it as a matrix and putting each corresponding starting piece at its place 0,0 is the top left spot of the board
public void populateBoard() {
// Black
setPiece(false, PieceType.Rook, 0, 0);
setPiece(false, PieceType.Knight, 1, 0);
setPiece(false, PieceType.Bishop, 2, 0);
setPiece(false, PieceType.Queen, 3, 0);
setPiece(false, PieceType.King, 4, 0);
setPiece(false, PieceType.Bishop, 5, 0);
setPiece(false, PieceType.Knight, 6, 0);
setPiece(false, PieceType.Rook, 7, 0);
// Black pawns
for (int i = 0; i < 8; i++) {
setPiece(false, PieceType.Pawn, i, 1);
}
// White pawns
for (int i = 0; i < 8; i++) {
setPiece(true, PieceType.Pawn, i, 6);
}
// White
setPiece(true, PieceType.Rook, 0, 7);
setPiece(true, PieceType.Knight, 1, 7);
setPiece(true, PieceType.Bishop, 2, 7);
setPiece(true, PieceType.Queen, 3, 7);
setPiece(true, PieceType.King, 4, 7);
setPiece(true, PieceType.Bishop, 5, 7);
setPiece(true, PieceType.Knight, 6, 7);
setPiece(true, PieceType.Rook, 7, 7);
}
public void cleanBoard() {
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
board[x][y] = null; // each position becomes empty
}
}
}
private void clearConsole() {
for (int i = 0; i < 50; i++) {
System.out.println(); // Print 50 empty lines to "clear" the console
}
}
public String toString() {
StringBuilder str = new StringBuilder();
str.append(" A B C D E F G H\n"); // columns letter at the top
// representation of the rows
for (int y = 0; y < height; y++) {
str.append(8 - y).append(" "); // row number on the left
for (int x = 0; x < width; x++) {
if (board[x][y] == null) {
str.append("- "); // empty positions
} else {
// convert each piece of both color into a character
Piece piece = board[x][y];
char pieceChar;
switch (piece.getType()) { // switch function avoids too many if-else
case King: pieceChar = 'K'; break;
case Queen: pieceChar = 'Q'; break;
case Bishop: pieceChar = 'B'; break;
case Knight: pieceChar = 'N'; break; // N because we already have King
case Rook: pieceChar = 'R'; break;
case Pawn: pieceChar = 'P'; break;
default: pieceChar = '?'; break; // safety net
}
// Make black pieces in lowercase
if (!piece.isWhite()) {
pieceChar = Character.toLowerCase(pieceChar);
}
str.append(pieceChar).append(" "); // gives structure to the output
}
}
str.append("\n"); // change of row
}
// Additional infos for a proper output
str.append("Turn ").append(getTurnNumber()).append(": ");
str.append(isTurnWhite() ? "White" : "Black");
return str.toString();
}
// list the placement of the pieces on the board
public ArrayList<Piece> getPieces() {
ArrayList<Piece> pieces = new ArrayList<>();
// collect infos for the non-empty positions
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
if (board[x][y] != null) {
pieces.add(board[x][y]);
}
}
}
return pieces;
}
// user clicks on the board
public void userTouch(int x, int y) {
if (selectedX == -1 && selectedY == -1) {
// check if the position is empty and the color
if (board[x][y] != null && board[x][y].isWhite() == isTurnWhite()) {
// select it as active location
selectedX = x;
selectedY = y;
highlightedPositions = getValidMoves(board[x][y]); // compute valid moves
}
} else {
if (x == selectedX && y == selectedY) {
// unselect it
selectedX = -1;
selectedY = -1;
highlightedPositions.clear();
} else {
// allow move if valid destination
boolean valid = false;
for (int[] pos : highlightedPositions) {
if (pos[0] == x && pos[1] == y) {
valid = true;
break;
}
}
if (valid) {
Piece pieceToMove = board[selectedX][selectedY];
board[x][y] = new Piece(x, y, pieceToMove.getType(), pieceToMove.isWhite());
board[selectedX][selectedY] = null;
incrementTurn();
}
// reset selection
selectedX = -1;
selectedY = -1;
highlightedPositions.clear();
clearConsole();
System.out.println(toString());
}
}
}
public boolean isSelected(int x, int y) {
return (x == selectedX && y == selectedY); // true if matching position
}
public boolean isHighlighted(int x, int y) { // checking for a given position if the square is highlighted or not
for (int[] pos : highlightedPositions) {
if (pos[0] == x && pos[1] == y) {
return true;
}
}
return false;
}
/* utility methods */
private boolean isInBounds(int x, int y) {
return x >= 0 && x < width && y >= 0 && y < height;
}
private void addLinearMoves(ArrayList<int[]> moves, int x, int y, Piece piece, int dx, int dy) {
int nx = x + dx;
int ny = y + dy;
while (isInBounds(nx, ny)) {
if (board[nx][ny] == null) {
moves.add(new int[]{nx, ny});
} else {
if (board[nx][ny].isWhite() != piece.isWhite()) {
moves.add(new int[]{nx, ny});
}
break;
}
nx += dx;
ny += dy;
}
}
private ArrayList<int[]> getValidMoves(Piece piece) {
ArrayList<int[]> moves = new ArrayList<>();
int x = piece.getX();
int y = piece.getY();
switch (piece.getType()) {
case Pawn:
int direction = piece.isWhite() ? -1 : 1;
int nextY = y + direction;
// forward move
if (isInBounds(x, nextY) && board[x][nextY] == null) {
moves.add(new int[]{x, nextY});
// double move from starting position
int startRow = piece.isWhite() ? 6 : 1;
int doubleStepY = y + 2 * direction;
if (y == startRow && isInBounds(x, doubleStepY) && board[x][doubleStepY] == null) {
moves.add(new int[]{x, doubleStepY});
}
}
// diagonal captures
for (int dx = -1; dx <= 1; dx += 2) {
int nx = x + dx;
if (isInBounds(nx, nextY) && board[nx][nextY] != null && board[nx][nextY].isWhite() != piece.isWhite()) {
moves.add(new int[]{nx, nextY});
}
}
break;
//for each piece, we calculate the positions it can end up in from an initial position
case Rook:
addLinearMoves(moves, x, y, piece, 1, 0);
addLinearMoves(moves, x, y, piece, -1, 0);
addLinearMoves(moves, x, y, piece, 0, 1);
addLinearMoves(moves, x, y, piece, 0, -1);
break;
case Bishop:
addLinearMoves(moves, x, y, piece, 1, 1);
addLinearMoves(moves, x, y, piece, -1, 1);
addLinearMoves(moves, x, y, piece, 1, -1);
addLinearMoves(moves, x, y, piece, -1, -1);
break;
case Queen:
for (int dx = -1; dx <= 1; dx++) {
for (int dy = -1; dy <= 1; dy++) {
if (dx != 0 || dy != 0) {
addLinearMoves(moves, x, y, piece, dx, dy);
}
}
}
break;
case King:
for (int dx = -1; dx <= 1; dx++) {
for (int dy = -1; dy <= 1; dy++) {
if (dx != 0 || dy != 0) {
int nx = x + dx;
int ny = y + dy;
if (isInBounds(nx, ny) && (board[nx][ny] == null || board[nx][ny].isWhite() != piece.isWhite())) {
moves.add(new int[]{nx, ny});
}
}
}
}
break;
case Knight:
int[][] jumps = {
{1, 2}, {2, 1}, {-1, 2}, {-2, 1}, // possible moves for
{-1, -2}, {-2, -1}, {1, -2}, {2, -1}
};
for (int[] j : jumps) {
int nx = x + j[0];
int ny = y + j[1];
if (isInBounds(nx, ny) && (board[nx][ny] == null || board[nx][ny].isWhite() != piece.isWhite())) {
moves.add(new int[]{nx, ny});
}
}
break;
}
return moves;
}
/* saving-loading feature : */
public String[] toFileRep() {
// TODO
return null;
}
public Board(String[] array) {
// TODO
}
/* additional functionality to implement later */
public void undoLastMove() {
// TODO
}
public void playMove(Move move) {
// TODO
}
public Board(Board board) {
// TODO
}
}