import { ArrayFun } from "@/utils/array";
-import { randInt, shuffle } from "@/utils/alea";
+import { randInt } from "@/utils/alea";
import { ChessRules, PiPo, Move } from "@/base_rules";
-export const VariantRules = class EightpiecesRules extends ChessRules {
+export class EightpiecesRules extends ChessRules {
static get JAILER() {
return "j";
}
return "l";
}
- static get PIECES() {
- return ChessRules.PIECES.concat([V.JAILER, V.SENTRY, V.LANCER]);
+ static get IMAGE_EXTENSION() {
+ // Temporarily, for the time SVG pieces are being designed:
+ return ".png";
}
+ // Lancer directions *from white perspective*
static get LANCER_DIRS() {
return {
'c': [-1, 0], //north
};
}
+ static get PIECES() {
+ return ChessRules.PIECES
+ .concat([V.JAILER, V.SENTRY])
+ .concat(Object.keys(V.LANCER_DIRS));
+ }
+
getPiece(i, j) {
const piece = this.board[i][j].charAt(1);
// Special lancer case: 8 possible orientations
return piece;
}
- getPpath(b) {
- return (
- ([V.JAILER, V.SENTRY, V.LANCER].includes(b[1])
- ? "Eightpieces/" : "") + b
+ getPpath(b, color, score, orientation) {
+ if ([V.JAILER, V.SENTRY].includes(b[1])) return "Eightpieces/tmp_png/" + b;
+ if (Object.keys(V.LANCER_DIRS).includes(b[1])) {
+ if (orientation == 'w') return "Eightpieces/tmp_png/" + b;
+ // Find opposite direction for adequate display:
+ let oppDir = '';
+ switch (b[1]) {
+ case 'c':
+ oppDir = 'g';
+ break;
+ case 'g':
+ oppDir = 'c';
+ break;
+ case 'd':
+ oppDir = 'h';
+ break;
+ case 'h':
+ oppDir = 'd';
+ break;
+ case 'e':
+ oppDir = 'm';
+ break;
+ case 'm':
+ oppDir = 'e';
+ break;
+ case 'f':
+ oppDir = 'o';
+ break;
+ case 'o':
+ oppDir = 'f';
+ break;
+ }
+ return "Eightpieces/tmp_png/" + b[0] + oppDir;
+ }
+ // TODO: after we have SVG pieces, remove the folder and next prefix:
+ return "Eightpieces/tmp_png/" + b;
+ }
+
+ getPPpath(b, orientation) {
+ return this.getPpath(b, null, null, orientation);
+ }
+
+ static ParseFen(fen) {
+ const fenParts = fen.split(" ");
+ return Object.assign(
+ ChessRules.ParseFen(fen),
+ { sentrypush: fenParts[5] }
);
}
+ static IsGoodFen(fen) {
+ if (!ChessRules.IsGoodFen(fen)) return false;
+ const fenParsed = V.ParseFen(fen);
+ // 5) Check sentry push (if any)
+ if (
+ fenParsed.sentrypush != "-" &&
+ !fenParsed.sentrypush.match(/^([a-h][1-8],?)+$/)
+ ) {
+ return false;
+ }
+ return true;
+ }
+
+ getFen() {
+ return super.getFen() + " " + this.getSentrypushFen();
+ }
+
+ getFenForRepeat() {
+ return super.getFenForRepeat() + "_" + this.getSentrypushFen();
+ }
+
+ getSentrypushFen() {
+ const L = this.sentryPush.length;
+ if (!this.sentryPush[L-1]) return "-";
+ let res = "";
+ this.sentryPush[L-1].forEach(coords =>
+ res += V.CoordsToSquare(coords) + ",");
+ return res.slice(0, -1);
+ }
+
setOtherVariables(fen) {
super.setOtherVariables(fen);
// subTurn == 2 only when a sentry moved, and is about to push something
this.subTurn = 1;
+ // Sentry position just after a "capture" (subTurn from 1 to 2)
+ this.sentryPos = null;
// Stack pieces' forbidden squares after a sentry move at each turn
- this.sentryPath = [];
+ const parsedFen = V.ParseFen(fen);
+ if (parsedFen.sentrypush == "-") this.sentryPush = [null];
+ else {
+ this.sentryPush = [
+ parsedFen.sentrypush.split(",").map(sq => {
+ return V.SquareToCoords(sq);
+ })
+ ];
+ }
+ }
+
+ static GenRandInitFen(randomness) {
+ if (randomness == 0)
+ // Deterministic:
+ return "jfsqkbnr/pppppppp/8/8/8/8/PPPPPPPP/JDSQKBNR w 0 ahah - -";
+
+ let pieces = { w: new Array(8), b: new Array(8) };
+ let flags = "";
+ // Shuffle pieces on first (and last rank if randomness == 2)
+ for (let c of ["w", "b"]) {
+ if (c == 'b' && randomness == 1) {
+ const lancerIdx = pieces['w'].findIndex(p => {
+ return Object.keys(V.LANCER_DIRS).includes(p);
+ });
+ pieces['b'] =
+ pieces['w'].slice(0, lancerIdx)
+ .concat(['g'])
+ .concat(pieces['w'].slice(lancerIdx + 1));
+ flags += flags;
+ break;
+ }
+
+ let positions = ArrayFun.range(8);
+
+ // Get random squares for bishop and sentry
+ let randIndex = 2 * randInt(4);
+ let bishopPos = positions[randIndex];
+ // The sentry must be on a square of different color
+ let randIndex_tmp = 2 * randInt(4) + 1;
+ let sentryPos = positions[randIndex_tmp];
+ if (c == 'b') {
+ // Check if white sentry is on the same color as ours.
+ // If yes: swap bishop and sentry positions.
+ // NOTE: test % 2 == 1 because there are 7 slashes.
+ if ((pieces['w'].indexOf('s') - sentryPos) % 2 == 1)
+ [bishopPos, sentryPos] = [sentryPos, bishopPos];
+ }
+ positions.splice(Math.max(randIndex, randIndex_tmp), 1);
+ positions.splice(Math.min(randIndex, randIndex_tmp), 1);
+
+ // Get random squares for knight and lancer
+ randIndex = randInt(6);
+ const knightPos = positions[randIndex];
+ positions.splice(randIndex, 1);
+ randIndex = randInt(5);
+ const lancerPos = positions[randIndex];
+ positions.splice(randIndex, 1);
+
+ // Get random square for queen
+ randIndex = randInt(4);
+ const queenPos = positions[randIndex];
+ positions.splice(randIndex, 1);
+
+ // Rook, jailer and king positions are now almost fixed,
+ // only the ordering rook->jailer or jailer->rook must be decided.
+ let rookPos = positions[0];
+ let jailerPos = positions[2];
+ const kingPos = positions[1];
+ flags += V.CoordToColumn(rookPos) + V.CoordToColumn(jailerPos);
+ if (Math.random() < 0.5) [rookPos, jailerPos] = [jailerPos, rookPos];
+
+ pieces[c][rookPos] = "r";
+ pieces[c][knightPos] = "n";
+ pieces[c][bishopPos] = "b";
+ pieces[c][queenPos] = "q";
+ pieces[c][kingPos] = "k";
+ pieces[c][sentryPos] = "s";
+ // Lancer faces north for white, and south for black:
+ pieces[c][lancerPos] = c == 'w' ? 'c' : 'g';
+ pieces[c][jailerPos] = "j";
+ }
+ return (
+ pieces["b"].join("") +
+ "/pppppppp/8/8/8/8/PPPPPPPP/" +
+ pieces["w"].join("").toUpperCase() +
+ " w 0 " + flags + " - -"
+ );
}
- canTake([x1,y1], [x2, y2]) {
+ canTake([x1, y1], [x2, y2]) {
if (this.subTurn == 2)
- // Sentry push: pieces can capture own color (only)
+ // Only self captures on this subturn:
return this.getColor(x1, y1) == this.getColor(x2, y2);
- return super.canTake([x1,y1], [x2, y2]);
+ return super.canTake([x1, y1], [x2, y2]);
}
- static GenRandInitFen(randomness) {
- // TODO: special conditions
- }
-
- // TODO: rook + jailer
- scanKingsRooks(fen) {
- this.kingPos = { w: [-1, -1], b: [-1, -1] };
- const fenRows = V.ParseFen(fen).position.split("/");
- for (let i = 0; i < fenRows.length; i++) {
- let k = 0; //column index on board
- for (let j = 0; j < fenRows[i].length; j++) {
- switch (fenRows[i].charAt(j)) {
- case "k":
- case "l":
- this.kingPos["b"] = [i, k];
- break;
- case "K":
- case "L":
- this.kingPos["w"] = [i, k];
- break;
- default: {
- const num = parseInt(fenRows[i].charAt(j));
- if (!isNaN(num)) k += num - 1;
+ // Is piece on square (x,y) immobilized?
+ isImmobilized([x, y]) {
+ const color = this.getColor(x, y);
+ const oppCol = V.GetOppCol(color);
+ 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
+ ) {
+ if (this.getPiece(i, j) == V.JAILER) return [i, j];
+ }
+ }
+ return null;
+ }
+
+ // Because of the lancers, getPiece() could be wrong:
+ // use board[x][y][1] instead (always valid).
+ getBasicMove([sx, sy], [ex, ey], tr) {
+ const initColor = this.getColor(sx, sy);
+ const initPiece = this.board[sx][sy].charAt(1);
+ let mv = new Move({
+ appear: [
+ new PiPo({
+ x: ex,
+ y: ey,
+ c: tr ? tr.c : initColor,
+ p: tr ? tr.p : initPiece
+ })
+ ],
+ vanish: [
+ new PiPo({
+ x: sx,
+ y: sy,
+ c: initColor,
+ p: initPiece
+ })
+ ]
+ });
+
+ // The opponent piece disappears if we take it
+ if (this.board[ex][ey] != V.EMPTY) {
+ mv.vanish.push(
+ new PiPo({
+ x: ex,
+ y: ey,
+ c: this.getColor(ex, ey),
+ p: this.board[ex][ey].charAt(1)
+ })
+ );
+ }
+
+ return mv;
+ }
+
+ canIplay(side, [x, y]) {
+ return (
+ (this.subTurn == 1 && this.turn == side && this.getColor(x, y) == side) ||
+ (this.subTurn == 2 && x == this.sentryPos.x && y == this.sentryPos.y)
+ );
+ }
+
+ getPotentialMovesFrom([x, y]) {
+ // At subTurn == 2, jailers aren't effective (Jeff K)
+ const piece = this.getPiece(x, y);
+ const L = this.sentryPush.length;
+ if (this.subTurn == 1) {
+ const jsq = this.isImmobilized([x, y]);
+ if (!!jsq) {
+ let moves = [];
+ // Special pass move if king:
+ if (piece == V.KING) {
+ moves.push(
+ new Move({
+ appear: [],
+ vanish: [],
+ start: { x: x, y: y },
+ end: { x: jsq[0], y: jsq[1] }
+ })
+ );
+ }
+ else if (piece == V.LANCER && !!this.sentryPush[L-1]) {
+ // A pushed lancer next to the jailer: reorient
+ const color = this.getColor(x, y);
+ const curDir = this.board[x][y].charAt(1);
+ Object.keys(V.LANCER_DIRS).forEach(k => {
+ moves.push(
+ new Move({
+ appear: [{ x: x, y: y, c: color, p: k }],
+ vanish: [{ x: x, y: y, c: color, p: curDir }],
+ start: { x: x, y: y },
+ end: { x: jsq[0], y: jsq[1] }
+ })
+ );
+ });
+ }
+ return moves;
+ }
+ }
+ let moves = [];
+ switch (piece) {
+ case V.JAILER:
+ moves = this.getPotentialJailerMoves([x, y]);
+ break;
+ case V.SENTRY:
+ moves = this.getPotentialSentryMoves([x, y]);
+ break;
+ case V.LANCER:
+ moves = this.getPotentialLancerMoves([x, y]);
+ break;
+ default:
+ moves = super.getPotentialMovesFrom([x, y]);
+ break;
+ }
+ if (!!this.sentryPush[L-1]) {
+ // Delete moves walking back on sentry push path,
+ // only if not a pawn, and the piece is the pushed one.
+ const pl = this.sentryPush[L-1].length;
+ const finalPushedSq = this.sentryPush[L-1][pl-1];
+ moves = moves.filter(m => {
+ if (
+ m.vanish[0].p != V.PAWN &&
+ m.start.x == finalPushedSq.x && m.start.y == finalPushedSq.y &&
+ this.sentryPush[L-1].some(sq => sq.x == m.end.x && sq.y == m.end.y)
+ ) {
+ return false;
+ }
+ return true;
+ });
+ } else if (this.subTurn == 2) {
+ // Put back the sentinel on board:
+ const color = this.turn;
+ moves.forEach(m => {
+ m.appear.push({x: x, y: y, p: V.SENTRY, c: color});
+ });
+ }
+ return moves;
+ }
+
+ getPotentialPawnMoves([x, y]) {
+ const color = this.getColor(x, y);
+ let moves = [];
+ const [sizeX, sizeY] = [V.size.x, V.size.y];
+ let shiftX = (color == "w" ? -1 : 1);
+ if (this.subTurn == 2) shiftX *= -1;
+ const firstRank = color == "w" ? sizeX - 1 : 0;
+ const startRank = color == "w" ? sizeX - 2 : 1;
+ const lastRank = color == "w" ? 0 : sizeX - 1;
+
+ // Pawns might be pushed on 1st rank and attempt to move again:
+ if (!V.OnBoard(x + shiftX, y)) return [];
+
+ const finalPieces =
+ // A push cannot put a pawn on last rank (it goes backward)
+ x + shiftX == lastRank
+ ? Object.keys(V.LANCER_DIRS).concat(
+ [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN, V.SENTRY, V.JAILER])
+ : [V.PAWN];
+ if (this.board[x + shiftX][y] == V.EMPTY) {
+ // One square forward
+ for (let piece of finalPieces) {
+ moves.push(
+ this.getBasicMove([x, y], [x + shiftX, y], {
+ c: color,
+ p: piece
+ })
+ );
+ }
+ if (
+ // 2-squares jumps forbidden if pawn push
+ this.subTurn == 1 &&
+ [startRank, firstRank].includes(x) &&
+ this.board[x + 2 * shiftX][y] == V.EMPTY
+ ) {
+ // Two squares jump
+ moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y]));
+ }
+ }
+ // Captures
+ for (let shiftY of [-1, 1]) {
+ if (
+ y + shiftY >= 0 &&
+ y + shiftY < sizeY &&
+ this.board[x + shiftX][y + shiftY] != V.EMPTY &&
+ this.canTake([x, y], [x + shiftX, y + shiftY])
+ ) {
+ for (let piece of finalPieces) {
+ moves.push(
+ this.getBasicMove([x, y], [x + shiftX, y + shiftY], {
+ c: color,
+ p: piece
+ })
+ );
+ }
+ }
+ }
+
+ // En passant: only on subTurn == 1
+ const Lep = this.epSquares.length;
+ const epSquare = this.epSquares[Lep - 1];
+ if (
+ this.subTurn == 1 &&
+ !!epSquare &&
+ epSquare.x == x + shiftX &&
+ Math.abs(epSquare.y - y) == 1
+ ) {
+ let enpassantMove = this.getBasicMove([x, y], [epSquare.x, epSquare.y]);
+ enpassantMove.vanish.push({
+ x: x,
+ y: epSquare.y,
+ p: "p",
+ c: this.getColor(x, epSquare.y)
+ });
+ moves.push(enpassantMove);
+ }
+
+ return moves;
+ }
+
+ // Obtain all lancer moves in "step" direction
+ getPotentialLancerMoves_aux([x, y], step, tr) {
+ let moves = [];
+ // Add all moves to vacant squares until opponent is met:
+ const color = this.getColor(x, y);
+ const oppCol =
+ this.subTurn == 1
+ ? V.GetOppCol(color)
+ // at subTurn == 2, consider own pieces as opponent
+ : color;
+ let sq = [x + step[0], y + step[1]];
+ while (V.OnBoard(sq[0], sq[1]) && this.getColor(sq[0], sq[1]) != oppCol) {
+ if (this.board[sq[0]][sq[1]] == V.EMPTY)
+ moves.push(this.getBasicMove([x, y], sq, tr));
+ sq[0] += step[0];
+ sq[1] += step[1];
+ }
+ if (V.OnBoard(sq[0], sq[1]))
+ // Add capturing move
+ moves.push(this.getBasicMove([x, y], sq, tr));
+ return moves;
+ }
+
+ getPotentialLancerMoves([x, y]) {
+ let moves = [];
+ // Add all lancer possible orientations, similar to pawn promotions.
+ // Except if just after a push: allow all movements from init square then
+ const L = this.sentryPush.length;
+ const color = this.getColor(x, y);
+ if (!!this.sentryPush[L-1]) {
+ // Maybe I was pushed
+ const pl = this.sentryPush[L-1].length;
+ if (
+ this.sentryPush[L-1][pl-1].x == x &&
+ this.sentryPush[L-1][pl-1].y == y
+ ) {
+ // I was pushed: allow all directions (for this move only), but
+ // do not change direction after moving, *except* if I keep the
+ // same orientation in which I was pushed.
+ const curDir = V.LANCER_DIRS[this.board[x][y].charAt(1)];
+ Object.values(V.LANCER_DIRS).forEach(step => {
+ const dirCode = Object.keys(V.LANCER_DIRS).find(k => {
+ return (
+ V.LANCER_DIRS[k][0] == step[0] &&
+ V.LANCER_DIRS[k][1] == step[1]
+ );
+ });
+ const dirMoves =
+ this.getPotentialLancerMoves_aux(
+ [x, y],
+ step,
+ { p: dirCode, c: color }
+ );
+ if (curDir[0] == step[0] && curDir[1] == step[1]) {
+ // Keeping same orientation: can choose after
+ let chooseMoves = [];
+ dirMoves.forEach(m => {
+ Object.keys(V.LANCER_DIRS).forEach(k => {
+ let mk = JSON.parse(JSON.stringify(m));
+ mk.appear[0].p = k;
+ moves.push(mk);
+ });
+ });
+ Array.prototype.push.apply(moves, chooseMoves);
+ } else Array.prototype.push.apply(moves, dirMoves);
+ });
+ return moves;
+ }
+ }
+ // I wasn't pushed: standard lancer move
+ const dirCode = this.board[x][y][1];
+ const monodirMoves =
+ this.getPotentialLancerMoves_aux([x, y], V.LANCER_DIRS[dirCode]);
+ // Add all possible orientations aftermove except if I'm being pushed
+ if (this.subTurn == 1) {
+ monodirMoves.forEach(m => {
+ Object.keys(V.LANCER_DIRS).forEach(k => {
+ let mk = JSON.parse(JSON.stringify(m));
+ mk.appear[0].p = k;
+ moves.push(mk);
+ });
+ });
+ return moves;
+ } else {
+ // I'm pushed: add potential nudges
+ let potentialNudges = [];
+ for (let step of V.steps[V.ROOK].concat(V.steps[V.BISHOP])) {
+ if (
+ V.OnBoard(x + step[0], y + step[1]) &&
+ this.board[x + step[0]][y + step[1]] == V.EMPTY
+ ) {
+ const newDirCode = Object.keys(V.LANCER_DIRS).find(k => {
+ const codeStep = V.LANCER_DIRS[k];
+ return (codeStep[0] == step[0] && codeStep[1] == step[1]);
+ });
+ potentialNudges.push(
+ this.getBasicMove(
+ [x, y],
+ [x + step[0], y + step[1]],
+ { c: color, p: newDirCode }
+ )
+ );
+ }
+ }
+ return monodirMoves.concat(potentialNudges);
+ }
+ }
+
+ getPotentialSentryMoves([x, y]) {
+ // The sentry moves a priori like a bishop:
+ let moves = super.getPotentialBishopMoves([x, y]);
+ // ...but captures are replaced by special move, if and only if
+ // "captured" piece can move now, considered as the capturer unit.
+ // --> except is subTurn == 2, in this case I don't push anything.
+ if (this.subTurn == 2) return moves.filter(m => m.vanish.length == 1);
+ moves.forEach(m => {
+ if (m.vanish.length == 2) {
+ // Temporarily cancel the sentry capture:
+ m.appear.pop();
+ m.vanish.pop();
+ }
+ });
+ const color = this.getColor(x, y);
+ const fMoves = moves.filter(m => {
+ // Can the pushed unit make any move? ...resulting in a non-self-check?
+ if (m.appear.length == 0) {
+ let res = false;
+ this.play(m);
+ let moves2 = this.getPotentialMovesFrom([m.end.x, m.end.y]);
+ for (let m2 of moves2) {
+ this.play(m2);
+ res = !this.underCheck(color);
+ this.undo(m2);
+ if (res) break;
+ }
+ this.undo(m);
+ return res;
+ }
+ return true;
+ });
+ return fMoves;
+ }
+
+ getPotentialJailerMoves([x, y]) {
+ return super.getPotentialRookMoves([x, y]).filter(m => {
+ // Remove jailer captures
+ return m.vanish[0].p != V.JAILER || m.vanish.length == 1;
+ });
+ }
+
+ getPotentialKingMoves(sq) {
+ const moves = this.getSlideNJumpMoves(
+ sq,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
+ "oneStep"
+ );
+ return (
+ this.subTurn == 1
+ ? moves.concat(this.getCastleMoves(sq))
+ : moves
+ );
+ }
+
+ atLeastOneMove() {
+ // If in second-half of a move, we already know that a move is possible
+ if (this.subTurn == 2) return true;
+ return super.atLeastOneMove();
+ }
+
+ filterValid(moves) {
+ if (moves.length == 0) return [];
+ const basicFilter = (m, c) => {
+ this.play(m);
+ const res = !this.underCheck(c);
+ this.undo(m);
+ return res;
+ };
+ // Disable check tests for sentry pushes,
+ // because in this case the move isn't finished
+ let movesWithoutSentryPushes = [];
+ let movesWithSentryPushes = [];
+ moves.forEach(m => {
+ // Second condition below for special king "pass" moves
+ if (m.appear.length > 0 || m.vanish.length == 0)
+ movesWithoutSentryPushes.push(m);
+ else movesWithSentryPushes.push(m);
+ });
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ const filteredMoves =
+ movesWithoutSentryPushes.filter(m => basicFilter(m, color));
+ // If at least one full move made, everything is allowed.
+ // Else: forbid checks and captures.
+ return (
+ this.movesCount >= 2
+ ? filteredMoves
+ : filteredMoves.filter(m => {
+ return (m.vanish.length <= 1 && basicFilter(m, oppCol));
+ })
+ ).concat(movesWithSentryPushes);
+ }
+
+ getAllValidMoves() {
+ if (this.subTurn == 1) return super.getAllValidMoves();
+ // Sentry push:
+ const sentrySq = [this.sentryPos.x, this.sentryPos.y];
+ return this.filterValid(this.getPotentialMovesFrom(sentrySq));
+ }
+
+ isAttacked(sq, color) {
+ return (
+ super.isAttacked(sq, color) ||
+ this.isAttackedByLancer(sq, color) ||
+ this.isAttackedBySentry(sq, color)
+ // The jailer doesn't capture.
+ );
+ }
+
+ isAttackedBySlideNJump([x, y], color, piece, steps, oneStep) {
+ for (let step of steps) {
+ let rx = x + step[0],
+ ry = y + step[1];
+ while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
+ rx += step[0];
+ ry += step[1];
+ }
+ if (
+ V.OnBoard(rx, ry) &&
+ this.getPiece(rx, ry) == piece &&
+ this.getColor(rx, ry) == color &&
+ !this.isImmobilized([rx, ry])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByPawn([x, y], color) {
+ const pawnShift = (color == "w" ? 1 : -1);
+ if (x + pawnShift >= 0 && x + pawnShift < V.size.x) {
+ for (let i of [-1, 1]) {
+ if (
+ y + i >= 0 &&
+ y + i < V.size.y &&
+ this.getPiece(x + pawnShift, y + i) == V.PAWN &&
+ this.getColor(x + pawnShift, y + i) == color &&
+ !this.isImmobilized([x + pawnShift, y + i])
+ ) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ isAttackedByLancer([x, y], color) {
+ for (let step of V.steps[V.ROOK].concat(V.steps[V.BISHOP])) {
+ // If in this direction there are only enemy pieces and empty squares,
+ // and we meet a lancer: can he reach us?
+ // NOTE: do not stop at first lancer, there might be several!
+ let coord = { x: x + step[0], y: y + step[1] };
+ let lancerPos = [];
+ while (
+ V.OnBoard(coord.x, coord.y) &&
+ (
+ this.board[coord.x][coord.y] == V.EMPTY ||
+ this.getColor(coord.x, coord.y) == color
+ )
+ ) {
+ if (
+ this.getPiece(coord.x, coord.y) == V.LANCER &&
+ !this.isImmobilized([coord.x, coord.y])
+ ) {
+ lancerPos.push({x: coord.x, y: coord.y});
+ }
+ coord.x += step[0];
+ coord.y += step[1];
+ }
+ for (let xy of lancerPos) {
+ const dir = V.LANCER_DIRS[this.board[xy.x][xy.y].charAt(1)];
+ if (dir[0] == -step[0] && dir[1] == -step[1]) return true;
+ }
+ }
+ return false;
+ }
+
+ // Helper to check sentries attacks:
+ selfAttack([x1, y1], [x2, y2]) {
+ const color = this.getColor(x1, y1);
+ const oppCol = V.GetOppCol(color);
+ const sliderAttack = (allowedSteps, lancer) => {
+ const deltaX = x2 - x1,
+ absDeltaX = Math.abs(deltaX);
+ const deltaY = y2 - y1,
+ absDeltaY = Math.abs(deltaY);
+ const step = [ deltaX / absDeltaX || 0, deltaY / absDeltaY || 0 ];
+ if (
+ // Check that the step is a priori valid:
+ (absDeltaX != absDeltaY && deltaX != 0 && deltaY != 0) ||
+ allowedSteps.every(st => st[0] != step[0] || st[1] != step[1])
+ ) {
+ return false;
+ }
+ let sq = [ x1 + step[0], y1 + step[1] ];
+ while (sq[0] != x2 || sq[1] != y2) {
+ if (
+ // NOTE: no need to check OnBoard in this special case
+ (!lancer && this.board[sq[0]][sq[1]] != V.EMPTY) ||
+ (!!lancer && this.getColor(sq[0], sq[1]) == oppCol)
+ ) {
+ return false;
+ }
+ sq[0] += step[0];
+ sq[1] += step[1];
+ }
+ return true;
+ };
+ switch (this.getPiece(x1, y1)) {
+ case V.PAWN: {
+ // Pushed pawns move as enemy pawns
+ const shift = (color == 'w' ? 1 : -1);
+ return (x1 + shift == x2 && Math.abs(y1 - y2) == 1);
+ }
+ case V.KNIGHT: {
+ const deltaX = Math.abs(x1 - x2);
+ const deltaY = Math.abs(y1 - y2);
+ return (
+ deltaX + deltaY == 3 &&
+ [1, 2].includes(deltaX) &&
+ [1, 2].includes(deltaY)
+ );
+ }
+ case V.ROOK:
+ return sliderAttack(V.steps[V.ROOK]);
+ case V.BISHOP:
+ return sliderAttack(V.steps[V.BISHOP]);
+ case V.QUEEN:
+ return sliderAttack(V.steps[V.ROOK].concat(V.steps[V.BISHOP]));
+ case V.LANCER: {
+ // Special case: as long as no enemy units stands in-between, it attacks
+ // (if it points toward the king).
+ const allowedStep = V.LANCER_DIRS[this.board[x1][y1].charAt(1)];
+ return sliderAttack([allowedStep], "lancer");
+ }
+ // No sentries or jailer tests: they cannot self-capture
+ }
+ return false;
+ }
+
+ isAttackedBySentry([x, y], color) {
+ // Attacked by sentry means it can self-take our king.
+ // Just check diagonals of enemy sentry(ies), and if it reaches
+ // one of our pieces: can I self-take?
+ const myColor = V.GetOppCol(color);
+ let candidates = [];
+ for (let i=0; i<V.size.x; i++) {
+ for (let j=0; j<V.size.y; j++) {
+ if (
+ this.getPiece(i,j) == V.SENTRY &&
+ this.getColor(i,j) == color &&
+ !this.isImmobilized([i, j])
+ ) {
+ for (let step of V.steps[V.BISHOP]) {
+ let sq = [ i + step[0], j + step[1] ];
+ while (
+ V.OnBoard(sq[0], sq[1]) &&
+ this.board[sq[0]][sq[1]] == V.EMPTY
+ ) {
+ sq[0] += step[0];
+ sq[1] += step[1];
+ }
+ if (
+ V.OnBoard(sq[0], sq[1]) &&
+ this.getColor(sq[0], sq[1]) == myColor
+ ) {
+ candidates.push([ sq[0], sq[1] ]);
+ }
}
}
- k++;
}
}
+ for (let c of candidates)
+ if (this.selfAttack(c, [x, y])) return true;
+ return false;
}
- getPotentialMovesFrom([x,y]) {
- // if subTurn == 2, allow only
+ // Jailer doesn't capture or give check
+
+ prePlay(move) {
+ if (move.appear.length == 0 && move.vanish.length == 1)
+ // The sentry is about to push a piece: subTurn goes from 1 to 2
+ this.sentryPos = { x: move.end.x, y: move.end.y };
+ if (this.subTurn == 2 && move.vanish[0].p != V.PAWN) {
+ // A piece is pushed: forbid array of squares between start and end
+ // of move, included (except if it's a pawn)
+ let squares = [];
+ if ([V.KNIGHT,V.KING].includes(move.vanish[0].p))
+ // short-range pieces: just forbid initial square
+ squares.push({ x: move.start.x, y: move.start.y });
+ else {
+ const deltaX = move.end.x - move.start.x;
+ const deltaY = move.end.y - move.start.y;
+ const step = [
+ deltaX / Math.abs(deltaX) || 0,
+ deltaY / Math.abs(deltaY) || 0
+ ];
+ for (
+ let sq = {x: move.start.x, y: move.start.y};
+ sq.x != move.end.x || sq.y != move.end.y;
+ sq.x += step[0], sq.y += step[1]
+ ) {
+ squares.push({ x: sq.x, y: sq.y });
+ }
+ }
+ // Add end square as well, to know if I was pushed (useful for lancers)
+ squares.push({ x: move.end.x, y: move.end.y });
+ this.sentryPush.push(squares);
+ } else this.sentryPush.push(null);
}
- // getPotentialMoves, isAttacked: TODO
- getPotentialCastleMoves(sq) { //TODO: adapt, with jailer
+ play(move) {
+ this.prePlay(move);
+ move.flags = JSON.stringify(this.aggregateFlags());
+ this.epSquares.push(this.getEpSquare(move));
+ V.PlayOnBoard(this.board, move);
+ // Is it a sentry push? (useful for undo)
+ move.sentryPush = (this.subTurn == 2);
+ if (this.subTurn == 1) this.movesCount++;
+ if (move.appear.length == 0 && move.vanish.length == 1) this.subTurn = 2;
+ else {
+ // Turn changes only if not a sentry "pre-push"
+ this.turn = V.GetOppCol(this.turn);
+ this.subTurn = 1;
+ }
+ this.postPlay(move);
}
- updateVariables(move) {
- // TODO: stack sentryPath if subTurn == 2 --> all squares between move.start et move.end, sauf si c'est un pion
+ postPlay(move) {
+ if (move.vanish.length == 0 || this.subTurn == 2)
+ // Special pass move of the king, or sentry pre-push: nothing to update
+ return;
+ const c = move.vanish[0].c;
+ const piece = move.vanish[0].p;
+ const firstRank = c == "w" ? V.size.x - 1 : 0;
+
+ if (piece == V.KING) {
+ this.kingPos[c][0] = move.appear[0].x;
+ this.kingPos[c][1] = move.appear[0].y;
+ this.castleFlags[c] = [V.size.y, V.size.y];
+ return;
+ }
+ // Update castling flags if rooks are moved
+ const oppCol = V.GetOppCol(c);
+ const oppFirstRank = V.size.x - 1 - firstRank;
+ if (
+ move.start.x == firstRank && //our rook moves?
+ this.castleFlags[c].includes(move.start.y)
+ ) {
+ const flagIdx = (move.start.y == this.castleFlags[c][0] ? 0 : 1);
+ this.castleFlags[c][flagIdx] = V.size.y;
+ } else if (
+ move.end.x == oppFirstRank && //we took opponent rook?
+ this.castleFlags[oppCol].includes(move.end.y)
+ ) {
+ const flagIdx = (move.end.y == this.castleFlags[oppCol][0] ? 0 : 1);
+ this.castleFlags[oppCol][flagIdx] = V.size.y;
+ }
}
- // TODO: special pass move: take jailer with king
+ undo(move) {
+ this.epSquares.pop();
+ this.disaggregateFlags(JSON.parse(move.flags));
+ V.UndoOnBoard(this.board, move);
+ // Decrement movesCount except if the move is a sentry push
+ if (!move.sentryPush) this.movesCount--;
+ if (this.subTurn == 2) this.subTurn = 1;
+ else {
+ this.turn = V.GetOppCol(this.turn);
+ if (move.sentryPush) this.subTurn = 2;
+ }
+ this.postUndo(move);
+ }
- // subTurn : if sentry moved to some enemy piece --> enregistrer déplacement sentry, subTurn == 2, puis déplacer pièce adverse --> 1st 1/2 of turn, vanish sentry tout simplement.
- // --> le turn ne change pas !
- // 2nd half: move only
- // FEN flag: sentryPath from init pushing to final enemy square --> forbid some moves (getPotentialMoves)
+ postUndo(move) {
+ super.postUndo(move);
+ this.sentryPush.pop();
+ }
static get VALUES() {
return Object.assign(
ChessRules.VALUES
);
}
+
+ getComputerMove() {
+ const maxeval = V.INFINITY;
+ const color = this.turn;
+ let moves1 = this.getAllValidMoves();
+
+ if (moves1.length == 0)
+ // TODO: this situation should not happen
+ return null;
+
+ const setEval = (move, next) => {
+ const score = this.getCurrentScore();
+ const curEval = move.eval;
+ if (score != "*") {
+ move.eval =
+ score == "1/2"
+ ? 0
+ : (score == "1-0" ? 1 : -1) * maxeval;
+ } else move.eval = this.evalPosition();
+ if (
+ // "next" is defined after sentry pushes
+ !!next && (
+ !curEval ||
+ color == 'w' && move.eval > curEval ||
+ color == 'b' && move.eval < curEval
+ )
+ ) {
+ move.second = next;
+ }
+ };
+
+ // Just search_depth == 1 (because of sentries. TODO: can do better...)
+ moves1.forEach(m1 => {
+ this.play(m1);
+ if (this.subTurn == 1) setEval(m1);
+ else {
+ // Need to play every pushes and count:
+ const moves2 = this.getAllValidMoves();
+ moves2.forEach(m2 => {
+ this.play(m2);
+ setEval(m1, m2);
+ this.undo(m2);
+ });
+ }
+ this.undo(m1);
+ });
+
+ moves1.sort((a, b) => {
+ return (color == "w" ? 1 : -1) * (b.eval - a.eval);
+ });
+ let candidates = [0];
+ for (let j = 1; j < moves1.length && moves1[j].eval == moves1[0].eval; j++)
+ candidates.push(j);
+ const choice = moves1[candidates[randInt(candidates.length)]];
+ return (!choice.second ? choice : [choice, choice.second]);
+ }
+
+ // For moves notation:
+ static get LANCER_DIRNAMES() {
+ return {
+ 'c': "N",
+ 'd': "NE",
+ 'e': "E",
+ 'f': "SE",
+ 'g': "S",
+ 'h': "SW",
+ 'm': "W",
+ 'o': "NW"
+ };
+ }
+
+ getNotation(move) {
+ // Special case "king takes jailer" is a pass move
+ if (move.appear.length == 0 && move.vanish.length == 0) return "pass";
+ let notation = undefined;
+ if (this.subTurn == 2) {
+ // Do not consider appear[1] (sentry) for sentry pushes
+ const simpleMove = {
+ appear: [move.appear[0]],
+ vanish: move.vanish,
+ start: move.start,
+ end: move.end
+ };
+ notation = super.getNotation(simpleMove);
+ } else notation = super.getNotation(move);
+ if (Object.keys(V.LANCER_DIRNAMES).includes(move.vanish[0].p))
+ // Lancer: add direction info
+ notation += "=" + V.LANCER_DIRNAMES[move.appear[0].p];
+ else if (
+ move.vanish[0].p == V.PAWN &&
+ Object.keys(V.LANCER_DIRNAMES).includes(move.appear[0].p)
+ ) {
+ // Fix promotions in lancer:
+ notation = notation.slice(0, -1) + "L:" + V.LANCER_DIRNAMES[move.appear[0].p];
+ }
+ return notation;
+ }
};
projects / vchess.git / blobdiff