+import { ChessRules, PiPo, Move } from "@/base_rules";
+import { ArrayFun } from "@/utils/array";
+import { randInt, shuffle } from "@/utils/alea";
+
+export class InterweaveRules extends ChessRules {
+ static get HasFlags() {
+ return false;
+ }
+
+ static GenRandInitFen(randomness) {
+ if (randomness == 0)
+ return "rbnkknbr/pppppppp/8/8/8/8/PPPPPPPP/RBNKKNBR w 0 - 000000";
+
+ let pieces = { w: new Array(8), b: new Array(8) };
+ for (let c of ["w", "b"]) {
+ if (c == 'b' && randomness == 1) {
+ pieces['b'] = pieces['w'];
+ break;
+ }
+
+ // Each pair of pieces on 2 colors:
+ const composition = ['r', 'n', 'b', 'k', 'r', 'n', 'b', 'k'];
+ let positions = shuffle(ArrayFun.range(4));
+ for (let i = 0; i < 4; i++)
+ pieces[c][2 * positions[i]] = composition[i];
+ positions = shuffle(ArrayFun.range(4));
+ for (let i = 0; i < 4; i++)
+ pieces[c][2 * positions[i] + 1] = composition[i];
+ }
+ return (
+ pieces["b"].join("") +
+ "/pppppppp/8/8/8/8/PPPPPPPP/" +
+ pieces["w"].join("").toUpperCase() +
+ // En-passant allowed, but no flags
+ " w 0 - 000000"
+ );
+ }
+
+ static IsGoodFen(fen) {
+ if (!ChessRules.IsGoodFen(fen)) return false;
+ const fenParsed = V.ParseFen(fen);
+ // 4) Check captures
+ if (!fenParsed.captured || !fenParsed.captured.match(/^[0-9]{6,6}$/))
+ return false;
+ return true;
+ }
+
+ static IsGoodPosition(position) {
+ if (position.length == 0) return false;
+ const rows = position.split("/");
+ if (rows.length != V.size.x) return false;
+ let kings = { "k": 0, "K": 0 };
+ for (let row of rows) {
+ let sumElts = 0;
+ for (let i = 0; i < row.length; i++) {
+ if (['K','k'].includes(row[i])) kings[row[i]]++;
+ if (V.PIECES.includes(row[i].toLowerCase())) sumElts++;
+ else {
+ const num = parseInt(row[i]);
+ if (isNaN(num)) return false;
+ sumElts += num;
+ }
+ }
+ if (sumElts != V.size.y) return false;
+ }
+ // Both kings should be on board. Exactly two per color.
+ if (Object.values(kings).some(v => v != 2)) return false;
+ return true;
+ }
+
+ static ParseFen(fen) {
+ const fenParts = fen.split(" ");
+ return Object.assign(
+ ChessRules.ParseFen(fen),
+ { captured: fenParts[4] }
+ );
+ }
+
+ getFen() {
+ return super.getFen() + " " + this.getCapturedFen();
+ }
+
+ getFenForRepeat() {
+ return super.getFenForRepeat() + "_" + this.getCapturedFen();
+ }
+
+ getCapturedFen() {
+ let counts = [...Array(6).fill(0)];
+ [V.ROOK, V.KNIGHT, V.BISHOP].forEach((p,idx) => {
+ counts[idx] = this.captured["w"][p];
+ counts[3 + idx] = this.captured["b"][p];
+ });
+ return counts.join("");
+ }
+
+ scanKings() {}
+
+ setOtherVariables(fen) {
+ super.setOtherVariables(fen);
+ const fenParsed = V.ParseFen(fen);
+ // Initialize captured pieces' counts from FEN
+ this.captured = {
+ w: {
+ [V.ROOK]: parseInt(fenParsed.captured[0]),
+ [V.KNIGHT]: parseInt(fenParsed.captured[1]),
+ [V.BISHOP]: parseInt(fenParsed.captured[2]),
+ },
+ b: {
+ [V.ROOK]: parseInt(fenParsed.captured[3]),
+ [V.KNIGHT]: parseInt(fenParsed.captured[4]),
+ [V.BISHOP]: parseInt(fenParsed.captured[5]),
+ }
+ };
+ // Stack of "last move" only for intermediate captures
+ this.lastMoveEnd = [null];
+ }
+
+ // Trim all non-capturing moves
+ static KeepCaptures(moves) {
+ return moves.filter(m => m.vanish.length >= 2 || m.appear.length == 0);
+ }
+
+ // Stop at the first capture found (if any)
+ atLeastOneCapture() {
+ const color = this.turn;
+ for (let i = 0; i < V.size.x; i++) {
+ for (let j = 0; j < V.size.y; j++) {
+ if (
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color &&
+ V.KeepCaptures(this.getPotentialMovesFrom([i, j])).length > 0
+ ) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ // En-passant after 2-sq jump
+ getEpSquare(moveOrSquare) {
+ if (!moveOrSquare) return undefined;
+ if (typeof moveOrSquare === "string") {
+ const square = moveOrSquare;
+ if (square == "-") return undefined;
+ // Enemy pawn initial column must be given too:
+ let res = [];
+ const epParts = square.split(",");
+ res.push(V.SquareToCoords(epParts[0]));
+ res.push(V.ColumnToCoord(epParts[1]));
+ return res;
+ }
+ // Argument is a move:
+ const move = moveOrSquare;
+ const [sx, ex, sy, ey] =
+ [move.start.x, move.end.x, move.start.y, move.end.y];
+ if (
+ move.vanish.length == 1 &&
+ this.getPiece(sx, sy) == V.PAWN &&
+ Math.abs(sx - ex) == 2 &&
+ Math.abs(sy - ey) == 2
+ ) {
+ return [
+ {
+ x: (ex + sx) / 2,
+ y: (ey + sy) / 2
+ },
+ // The arrival column must be remembered, because
+ // potentially two pawns could be candidates to be captured:
+ // one on our left, and one on our right.
+ move.end.y
+ ];
+ }
+ return undefined; //default
+ }
+
+ static IsGoodEnpassant(enpassant) {
+ if (enpassant != "-") {
+ const epParts = enpassant.split(",");
+ const epSq = V.SquareToCoords(epParts[0]);
+ if (isNaN(epSq.x) || isNaN(epSq.y) || !V.OnBoard(epSq)) return false;
+ const arrCol = V.ColumnToCoord(epParts[1]);
+ if (isNaN(arrCol) || arrCol < 0 || arrCol >= V.size.y) return false;
+ }
+ return true;
+ }
+
+ getEnpassantFen() {
+ const L = this.epSquares.length;
+ if (!this.epSquares[L - 1]) return "-"; //no en-passant
+ return (
+ V.CoordsToSquare(this.epSquares[L - 1][0]) +
+ "," +
+ V.CoordToColumn(this.epSquares[L - 1][1])
+ );
+ }
+
+ getPotentialMovesFrom([x, y], noPostprocess) {
+ const L = this.lastMoveEnd.length;
+ if (
+ !!this.lastMoveEnd[L-1] &&
+ (
+ x != this.lastMoveEnd[L-1].x ||
+ y != this.lastMoveEnd[L-1].y
+ )
+ ) {
+ // A capture must continue: wrong square
+ return [];
+ }
+ let moves = [];
+ switch (this.getPiece(x, y)) {
+ case V.PAWN:
+ moves = this.getPotentialPawnMoves([x, y]);
+ break;
+ case V.ROOK:
+ moves = this.getPotentialRookMoves([x, y]);
+ break;
+ case V.KNIGHT:
+ moves = this.getPotentialKnightMoves([x, y]);
+ break;
+ case V.BISHOP:
+ moves = this.getPotentialBishopMoves([x, y]);
+ break;
+ case V.KING:
+ moves = this.getPotentialKingMoves([x, y]);
+ break;
+ // No queens
+ }
+ if (!noPostprocess) {
+ // Post-process: if capture,
+ // can another capture be achieved with the same piece?
+ moves.forEach(m => {
+ if (m.vanish.length >= 2 || m.appear.length == 0) {
+ this.play(m);
+ const moreCaptures = (
+ V.KeepCaptures(
+ this.getPotentialMovesFrom([m.end.x, m.end.y], "noPostprocess")
+ )
+ .length > 0
+ );
+ this.undo(m);
+ if (!moreCaptures) m.last = true;
+ }
+ else m.last = true;
+ });
+ }
+ return moves;
+ }
+
+ // Special pawns movements
+ getPotentialPawnMoves([x, y]) {
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ let moves = [];
+ const [sizeX, sizeY] = [V.size.x, V.size.y];
+ const shiftX = color == "w" ? -1 : 1;
+ const startRank = color == "w" ? sizeX - 2 : 1;
+ const potentialFinalPieces =
+ [V.ROOK, V.KNIGHT, V.BISHOP].filter(p => this.captured[color][p] > 0);
+ const lastRanks = (color == "w" ? [0, 1] : [sizeX - 1, sizeX - 2]);
+ if (x + shiftX == lastRanks[0] && potentialFinalPieces.length == 0)
+ // If no captured piece is available, the pawn cannot promote
+ return [];
+
+ const finalPieces1 =
+ x + shiftX == lastRanks[0]
+ ? potentialFinalPieces
+ :
+ x + shiftX == lastRanks[1]
+ ? potentialFinalPieces.concat([V.PAWN])
+ : [V.PAWN];
+ // One square diagonally
+ for (let shiftY of [-1, 1]) {
+ if (this.board[x + shiftX][y + shiftY] == V.EMPTY) {
+ for (let piece of finalPieces1) {
+ moves.push(
+ this.getBasicMove([x, y], [x + shiftX, y + shiftY], {
+ c: color,
+ p: piece
+ })
+ );
+ }
+ if (
+ V.PawnSpecs.twoSquares &&
+ x == startRank &&
+ y + 2 * shiftY >= 0 &&
+ y + 2 * shiftY < sizeY &&
+ this.board[x + 2 * shiftX][y + 2 * shiftY] == V.EMPTY
+ ) {
+ // Two squares jump
+ moves.push(
+ this.getBasicMove([x, y], [x + 2 * shiftX, y + 2 * shiftY])
+ );
+ }
+ }
+ }
+ // Capture
+ const finalPieces2 =
+ x + 2 * shiftX == lastRanks[0]
+ ? potentialFinalPieces
+ :
+ x + 2 * shiftX == lastRanks[1]
+ ? potentialFinalPieces.concat([V.PAWN])
+ : [V.PAWN];
+ if (
+ this.board[x + shiftX][y] != V.EMPTY &&
+ this.canTake([x, y], [x + shiftX, y]) &&
+ V.OnBoard(x + 2 * shiftX, y) &&
+ this.board[x + 2 * shiftX][y] == V.EMPTY
+ ) {
+ const oppPiece = this.getPiece(x + shiftX, y);
+ for (let piece of finalPieces2) {
+ let mv = this.getBasicMove(
+ [x, y], [x + 2 * shiftX, y], { c: color, p: piece });
+ mv.vanish.push({
+ x: x + shiftX,
+ y: y,
+ p: oppPiece,
+ c: oppCol
+ });
+ moves.push(mv);
+ }
+ }
+
+ // En passant
+ const Lep = this.epSquares.length;
+ const epSquare = this.epSquares[Lep - 1]; //always at least one element
+ if (
+ !!epSquare &&
+ epSquare[0].x == x + shiftX &&
+ epSquare[0].y == y &&
+ this.board[x + 2 * shiftX][y] == V.EMPTY
+ ) {
+ for (let piece of finalPieces2) {
+ let enpassantMove =
+ this.getBasicMove(
+ [x, y], [x + 2 * shiftX, y], { c: color, p: piece});
+ enpassantMove.vanish.push({
+ x: x,
+ y: epSquare[1],
+ p: "p",
+ c: this.getColor(x, epSquare[1])
+ });
+ moves.push(enpassantMove);
+ }
+ }
+
+ // Add custodian captures:
+ const steps = V.steps[V.ROOK];
+ moves.forEach(m => {
+ // Try capturing in every direction
+ for (let step of steps) {
+ const sq2 = [m.end.x + 2 * step[0], m.end.y + 2 * step[1]];
+ if (
+ V.OnBoard(sq2[0], sq2[1]) &&
+ this.board[sq2[0]][sq2[1]] != V.EMPTY &&
+ this.getColor(sq2[0], sq2[1]) == color
+ ) {
+ // Potential capture
+ const sq1 = [m.end.x + step[0], m.end.y + step[1]];
+ if (
+ this.board[sq1[0]][sq1[1]] != V.EMPTY &&
+ this.getColor(sq1[0], sq1[1]) == oppCol
+ ) {
+ m.vanish.push(
+ new PiPo({
+ x: sq1[0],
+ y: sq1[1],
+ c: oppCol,
+ p: this.getPiece(sq1[0], sq1[1])
+ })
+ );
+ }
+ }
+ }
+ });
+
+ return moves;
+ }
+
+ getSlides([x, y], steps, options) {
+ options = options || {};
+ // No captures:
+ let moves = [];
+ outerLoop: for (let step of steps) {
+ let i = x + step[0];
+ let j = y + step[1];
+ let counter = 1;
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ if (!options["doubleStep"] || counter % 2 == 0)
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ if (!!options["oneStep"]) continue outerLoop;
+ i += step[0];
+ j += step[1];
+ counter++;
+ }
+ }
+ return moves;
+ }
+
+ // Smasher
+ getPotentialRookMoves([x, y]) {
+ let moves =
+ this.getSlides([x, y], V.steps[V.ROOK], { doubleStep: true })
+ .concat(this.getSlides([x, y], V.steps[V.BISHOP]));
+ // Add captures
+ const oppCol = V.GetOppCol(this.turn);
+ moves.forEach(m => {
+ const delta = [m.end.x - m.start.x, m.end.y - m.start.y];
+ const step = [
+ delta[0] / Math.abs(delta[0]) || 0,
+ delta[1] / Math.abs(delta[1]) || 0
+ ];
+ if (step[0] == 0 || step[1] == 0) {
+ // Rook-like move, candidate for capturing
+ const [i, j] = [m.end.x + step[0], m.end.y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == oppCol
+ ) {
+ m.vanish.push({
+ x: i,
+ y: j,
+ p: this.getPiece(i, j),
+ c: oppCol
+ });
+ }
+ }
+ });
+ return moves;
+ }
+
+ // Leaper
+ getPotentialKnightMoves([x, y]) {
+ let moves =
+ this.getSlides([x, y], V.steps[V.ROOK], { doubleStep: true })
+ .concat(this.getSlides([x, y], V.steps[V.BISHOP]));
+ const oppCol = V.GetOppCol(this.turn);
+ // Look for double-knight moves (could capture):
+ for (let step of V.steps[V.KNIGHT]) {
+ const [i, j] = [x + 2 * step[0], y + 2 * step[1]];
+ if (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ const [ii, jj] = [x + step[0], y + step[1]];
+ if (this.board[ii][jj] == V.EMPTY || this.getColor(ii, jj) == oppCol) {
+ let mv = this.getBasicMove([x, y], [i, j]);
+ if (this.board[ii][jj] != V.EMPTY) {
+ mv.vanish.push({
+ x: ii,
+ y: jj,
+ c: oppCol,
+ p: this.getPiece(ii, jj)
+ });
+ }
+ moves.push(mv);
+ }
+ }
+ }
+ // Look for an enemy in every orthogonal direction
+ for (let step of V.steps[V.ROOK]) {
+ let [i, j] = [x + step[0], y+ step[1]];
+ let counter = 1;
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ i += step[0];
+ j += step[1];
+ counter++;
+ }
+ if (
+ V.OnBoard(i, j) &&
+ counter % 2 == 1 &&
+ this.getColor(i, j) == oppCol
+ ) {
+ const oppPiece = this.getPiece(i, j);
+ // Candidate for capture: can I land after?
+ let [ii, jj] = [i + step[0], j + step[1]];
+ counter++;
+ while (V.OnBoard(ii, jj) && this.board[ii][jj] == V.EMPTY) {
+ if (counter % 2 == 0) {
+ // Same color: add capture
+ let mv = this.getBasicMove([x, y], [ii, jj]);
+ mv.vanish.push({
+ x: i,
+ y: j,
+ c: oppCol,
+ p: oppPiece
+ });
+ moves.push(mv);
+ }
+ ii += step[0];
+ jj += step[1];
+ counter++;
+ }
+ }
+ }
+ return moves;
+ }
+
+ // Remover
+ getPotentialBishopMoves([x, y]) {
+ let moves = this.getSlides([x, y], V.steps[V.BISHOP]);
+ // Add captures
+ const oppCol = V.GetOppCol(this.turn);
+ let captures = [];
+ for (let step of V.steps[V.ROOK]) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == oppCol
+ ) {
+ captures.push([i, j]);
+ }
+ }
+ captures.forEach(c => {
+ moves.push({
+ start: { x: x, y: y },
+ end: { x: c[0], y: c[1] },
+ appear: [],
+ vanish: captures.map(ct => {
+ return {
+ x: ct[0],
+ y: ct[1],
+ c: oppCol,
+ p: this.getPiece(ct[0], ct[1])
+ };
+ })
+ });
+ });
+ return moves;
+ }
+
+ getPotentialKingMoves([x, y]) {
+ let moves = this.getSlides([x, y], V.steps[V.BISHOP], { oneStep: true });
+ // Add captures
+ const oppCol = V.GetOppCol(this.turn);
+ for (let step of V.steps[V.ROOK]) {
+ const [i, j] = [x + 2 * step[0], y + 2 * step[1]];
+ if (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ const [ii, jj] = [x + step[0], y + step[1]];
+ if (this.board[ii][jj] != V.EMPTY && this.getColor(ii, jj) == oppCol) {
+ let mv = this.getBasicMove([x, y], [i, j]);
+ mv.vanish.push({
+ x: ii,
+ y: jj,
+ c: oppCol,
+ p: this.getPiece(ii, jj)
+ });
+ moves.push(mv);
+ }
+ }
+ }
+ return moves;
+ }
+
+ getPossibleMovesFrom(sq) {
+ const L = this.lastMoveEnd.length;
+ if (
+ !!this.lastMoveEnd[L-1] &&
+ (
+ sq[0] != this.lastMoveEnd[L-1].x ||
+ sq[1] != this.lastMoveEnd[L-1].y
+ )
+ ) {
+ return [];
+ }
+ let moves = this.getPotentialMovesFrom(sq);
+ const captureMoves = V.KeepCaptures(moves);
+ if (captureMoves.length > 0) return captureMoves;
+ if (this.atLeastOneCapture()) return [];
+ return moves;
+ }
+
+ getAllValidMoves() {
+ const moves = this.getAllPotentialMoves();
+ const captures = V.KeepCaptures(moves);
+ if (captures.length > 0) return captures;
+ return moves;
+ }
+
+ filterValid(moves) {
+ // No checks
+ return moves;
+ }
+
+ play(move) {
+ this.epSquares.push(this.getEpSquare(move));
+ V.PlayOnBoard(this.board, move);
+ if (move.vanish.length >= 2) {
+ // Capture: update this.captured
+ for (let i=1; i<move.vanish.length; i++)
+ this.captured[move.vanish[i].c][move.vanish[i].p]++;
+ }
+ if (!!move.last) {
+ // No capture, or no more capture available
+ this.turn = V.GetOppCol(this.turn);
+ this.movesCount++;
+ this.lastMoveEnd.push(null);
+ }
+ else this.lastMoveEnd.push(move.end);
+ }
+
+ undo(move) {
+ this.epSquares.pop();
+ this.lastMoveEnd.pop();
+ V.UndoOnBoard(this.board, move);
+ if (move.vanish.length >= 2) {
+ for (let i=1; i<move.vanish.length; i++)
+ this.captured[move.vanish[i].c][move.vanish[i].p]--;
+ }
+ if (!!move.last) {
+ this.turn = V.GetOppCol(this.turn);
+ this.movesCount--;
+ }
+ }
+
+ getCheckSquares() {
+ return [];
+ }
+
+ getCurrentScore() {
+ // Count kings: if one is missing, the side lost
+ let kingsCount = { 'w': 0, 'b': 0 };
+ for (let i=0; i<8; i++) {
+ for (let j=0; j<8; j++) {
+ if (this.board[i][j] != V.EMPTY && this.getPiece(i, j) == V.KING)
+ kingsCount[this.getColor(i, j)]++;
+ }
+ }
+ if (kingsCount['w'] < 2) return "0-1";
+ if (kingsCount['b'] < 2) return "1-0";
+ return "*";
+ }
+
+ getComputerMove() {
+ let moves = this.getAllValidMoves();
+ if (moves.length == 0) return null;
+ // Just play random moves (for now at least. TODO?)
+ let mvArray = [];
+ while (moves.length > 0) {
+ const mv = moves[randInt(moves.length)];
+ mvArray.push(mv);
+ if (!mv.last) {
+ this.play(mv);
+ moves = V.KeepCaptures(
+ this.getPotentialMovesFrom([mv.end.x, mv.end.y]));
+ }
+ else break;
+ }
+ for (let i = mvArray.length - 2; i >= 0; i--) this.undo(mvArray[i]);
+ return (mvArray.length > 1 ? mvArray : mvArray[0]);
+ }
+
+ getNotation(move) {
+ const initialSquare = V.CoordsToSquare(move.start);
+ const finalSquare = V.CoordsToSquare(move.end);
+ if (move.appear.length == 0)
+ // Remover captures 'R'
+ return initialSquare + "R";
+ let notation = move.appear[0].p.toUpperCase() + finalSquare;
+ // Add a capture mark (not describing what is captured...):
+ if (move.vanish.length >= 2) notation += "X";
+ return notation;
+ }
+};
projects / vchess.git / commitdiff