+import { ChessRules, PiPo, Move } from "@/base_rules";
+
+export const VariantRules = class BenedictRules extends ChessRules {
+ static get HasEnpassant() {
+ return false;
+ }
+
+ // TODO(?): some duplicated code in 2 next functions
+ getSlideNJumpMoves([x, y], steps, oneStep) {
+ let moves = [];
+ outerLoop: for (let loop = 0; loop < steps.length; loop++) {
+ const step = steps[loop];
+ let i = x + step[0];
+ let j = y + step[1];
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ if (oneStep) continue outerLoop;
+ i += step[0];
+ j += step[1];
+ }
+ // No capture check: handled elsewhere (next method)
+ }
+ return moves;
+ }
+
+ // Find possible captures from a square
+ // follow steps from x,y until something is met.
+ findCaptures([x, y]) {
+ const color = this.getColor(x, y);
+ const piece = this.getPiece(x, y);
+ let squares = [];
+ const steps =
+ piece != V.PAWN
+ ? [V.QUEEN,V.KING].includes(piece)
+ ? V.steps[V.ROOK].concat(V.steps[V.BISHOP])
+ : V.steps[piece]
+ : color == "w"
+ ? [
+ [-1, -1],
+ [-1, 1]
+ ]
+ : [
+ [1, -1],
+ [1, 1]
+ ];
+ const oneStep = [V.KNIGHT,V.PAWN,V.KING].includes(piece);
+ outerLoop: for (let loop = 0; loop < steps.length; loop++) {
+ const step = steps[loop];
+ let i = x + step[0];
+ let j = y + step[1];
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ if (oneStep) continue outerLoop;
+ i += step[0];
+ j += step[1];
+ }
+ if (
+ V.OnBoard(i, j) &&
+ this.getColor(i, j) == V.GetOppCol(color)
+ ) {
+ // eat!
+ squares.push([i, j]);
+ }
+ }
+ return squares;
+ }
+
+ getPotentialPawnMoves([x, y]) {
+ const color = this.getColor(x, y);
+ let moves = [];
+ const sizeY = V.size.y;
+ const shift = color == "w" ? -1 : 1;
+ const startRank = color == "w" ? sizeY - 2 : 1;
+ const firstRank = color == "w" ? sizeY - 1 : 0;
+ const lastRank = color == "w" ? 0 : sizeY - 1;
+
+ if (x + shift != lastRank) {
+ // Normal moves
+ if (this.board[x + shift][y] == V.EMPTY) {
+ moves.push(this.getBasicMove([x, y], [x + shift, y]));
+ if (
+ [startRank, firstRank].includes(x) &&
+ this.board[x + 2 * shift][y] == V.EMPTY
+ ) {
+ // Two squares jump
+ moves.push(this.getBasicMove([x, y], [x + 2 * shift, y]));
+ }
+ }
+ }
+ else {
+ // Promotion
+ let promotionPieces = [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN];
+ promotionPieces.forEach(p => {
+ // Normal move
+ if (this.board[x + shift][y] == V.EMPTY)
+ moves.push(
+ this.getBasicMove([x, y], [x + shift, y], { c: color, p: p })
+ );
+ });
+ }
+
+ // No en passant here
+
+ return moves;
+ }
+
+ getPotentialRookMoves(sq) {
+ return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]);
+ }
+
+ getPotentialKnightMoves(sq) {
+ return this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep");
+ }
+
+ getPotentialBishopMoves(sq) {
+ return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]);
+ }
+
+ getPotentialQueenMoves(sq) {
+ return this.getSlideNJumpMoves(
+ sq,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP])
+ );
+ }
+
+ getPotentialKingMoves(sq) {
+ // Initialize with normal (non-capturing) moves
+ let noCaptures = this.getSlideNJumpMoves(
+ sq,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
+ "oneStep"
+ );
+ return noCaptures.concat(this.getCastleMoves(sq));
+ }
+
+ // TODO: appear/vanish description of a move is too verbose for Benedict.
+ // => Would need a new "flipped" array, to be passed in Game.vue...
+ getPotentialMovesFrom([x, y]) {
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ // Get all moves from x,y without captures:
+ let moves = super.getPotentialMovesFrom([x, y]);
+ // Add flips:
+ moves.forEach(m => {
+ V.PlayOnBoard(this.board, m);
+ const flipped = this.findCaptures([m.end.x, m.end.y]);
+ V.UndoOnBoard(this.board, m);
+ flipped.forEach(sq => {
+ const piece = this.getPiece(sq[0],sq[1]);
+ const pipoA = new PiPo({
+ x:sq[0],
+ y:sq[1],
+ c:color,
+ p:piece
+ });
+ const pipoV = new PiPo({
+ x:sq[0],
+ y:sq[1],
+ c:oppCol,
+ p:piece
+ });
+ m.appear.push(pipoA);
+ m.vanish.push(pipoV);
+ });
+ });
+ return moves;
+ }
+
+ // Moves cannot flip our king's color, so all are valid
+ filterValid(moves) {
+ return moves;
+ }
+
+ // No notion of check here:
+ getCheckSquares() {
+ return [];
+ }
+
+ getCurrentScore() {
+ const color = this.turn;
+ // Did a king change color?
+ const kp = this.kingPos[color];
+ if (this.getColor(kp[0], kp[1]) != color)
+ return color == "w" ? "0-1" : "1-0";
+ return "*";
+ }
+};
projects / vchess.git / commitdiff
