--- /dev/null
+import { ChessRules, PiPo, Move } from "@/base_rules";
+import { ArrayFun } from "@/utils/array";
+import { shuffle } from "@/utils/alea";
+
+export class MaximaRules extends ChessRules {
+ static get HasFlags() {
+ return false;
+ }
+
+ static get HasEnpassant() {
+ return false;
+ }
+
+ static get PIECES() {
+ return ChessRules.PIECES.concat([V.IMMOBILIZER, V.MAGE, V.GUARD]);
+ }
+
+ getPpath(b) {
+ if (b[0] == 'x') return "Maxima/nothing";
+ if (['m','d','g'].includes(b[1]))
+ return "Maxima/" + b;
+ return b;
+ }
+
+ // For space next to the palaces:
+ static get NOTHING() {
+ return "xx";
+ }
+
+ static board2fen(b) {
+ if (b[0] == 'x') return 'x';
+ return ChessRules.board2fen(b);
+ }
+
+ static fen2board(f) {
+ if (f == 'x') return V.NOTHING;
+ return ChessRules.fen2board(f);
+ }
+
+ // TODO: the wall position should be checked too
+ 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 (['x'].concat(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;
+ }
+ if (Object.values(kings).some(v => v != 1)) return false;
+ return true;
+ }
+
+ // No castling, but checks, so keep track of kings
+ setOtherVariables(fen) {
+ this.kingPos = { w: [-1, -1], b: [-1, -1] };
+ const fenParts = fen.split(" ");
+ const position = fenParts[0].split("/");
+ for (let i = 0; i < position.length; i++) {
+ let k = 0;
+ for (let j = 0; j < position[i].length; j++) {
+ switch (position[i].charAt(j)) {
+ case "k":
+ this.kingPos["b"] = [i, k];
+ break;
+ case "K":
+ this.kingPos["w"] = [i, k];
+ break;
+ default: {
+ const num = parseInt(position[i].charAt(j));
+ if (!isNaN(num)) k += num - 1;
+ }
+ }
+ k++;
+ }
+ }
+ }
+
+ static get size() {
+ return { x: 11, y: 8 };
+ }
+
+ static OnBoard(x, y) {
+ return (
+ (x >= 1 && x <= 9 && y >= 0 && y <= 7) ||
+ ([3, 4].includes(y) && [0, 10].includes(x))
+ );
+ }
+
+ static get IMMOBILIZER() {
+ return "m";
+ }
+ static get MAGE() {
+ return 'g';
+ }
+ static get GUARD() {
+ return 'd';
+ }
+ // Although other pieces keep their names here for coding simplicity,
+ // keep in mind that:
+ // - a "rook" is a coordinator, capturing by coordinating with the king
+ // - a "knight" is a long-leaper, capturing as in draughts
+ // - a "bishop" is a chameleon, capturing as its prey
+ // - a "queen" is a withdrawer, capturing by moving away from pieces
+
+ // Is piece on square (x,y) immobilized?
+ isImmobilized([x, y]) {
+ const piece = this.getPiece(x, y);
+ if (piece == V.MAGE)
+ // Mages are not immobilized:
+ return false;
+ const oppCol = V.GetOppCol(this.getColor(x, y));
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ 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
+ ) {
+ const oppPiece = this.getPiece(i, j);
+ if (oppPiece == V.IMMOBILIZER) return [i, j];
+ // Only immobilizers are immobilized by chameleons:
+ if (oppPiece == V.BISHOP && piece == V.IMMOBILIZER) return [i, j];
+ }
+ }
+ return null;
+ }
+
+ getPotentialMovesFrom([x, y]) {
+ // Pre-check: is thing on this square immobilized?
+ const imSq = this.isImmobilized([x, y]);
+ const piece = this.getPiece(x, y);
+ if (!!imSq && piece != V.KING) {
+ // Only option is suicide, if I'm not a king:
+ return [
+ new Move({
+ start: { x: x, y: y },
+ end: { x: imSq[0], y: imSq[1] },
+ appear: [],
+ vanish: [
+ new PiPo({
+ x: x,
+ y: y,
+ c: this.getColor(x, y),
+ p: this.getPiece(x, y)
+ })
+ ]
+ })
+ ];
+ }
+ let moves = undefined;
+ switch (piece) {
+ case V.IMMOBILIZER:
+ moves = this.getPotentialImmobilizerMoves([x, y]);
+ break;
+ case V.GUARD:
+ moves = this.getPotentialGuardMoves([x, y]);
+ break;
+ case V.MAGE:
+ moves = this.getPotentialMageMoves([x, y]);
+ break;
+ default:
+ moves = super.getPotentialMovesFrom([x, y]);
+ }
+ const pX = (this.turn == 'w' ? 10 : 0);
+ if (this.board[pX][3] == V.EMPTY && this.board[pX][4] == V.EMPTY)
+ return moves;
+ // Filter out moves resulting in self palace occupation:
+ // NOTE: cannot invade own palace but still check the king there.
+ const pY = (this.board[pX][3] == V.EMPTY ? 4 : 3);
+ return moves.filter(m => m.end.x != pX || m.end.y != pY);
+ }
+
+ getSlideNJumpMoves([x, y], steps, oneStep, mageInitSquare, onlyTake) {
+ const piece = !mageInitSquare ? this.getPiece(x, y) : V.MAGE;
+ const initSquare = mageInitSquare || [x, y];
+ let moves = [];
+ outerLoop: for (let step of steps) {
+ let i = x + step[0];
+ let j = y + step[1];
+ if (piece == V.KING) j = j % V.size.y;
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ if (!onlyTake) moves.push(this.getBasicMove(initSquare, [i, j]));
+ if (!!oneStep) continue outerLoop;
+ i += step[0];
+ j += step[1];
+ }
+ // Only king, guard and mage + chameleon can take on occupied square:
+ if (
+ V.OnBoard(i, j)
+ &&
+ this.canTake(initSquare, [i, j])
+ &&
+ (
+ [V.KING, V.GUARD, V.MAGE].includes(piece) ||
+ (piece == V.BISHOP && this.getPiece(i, j) === onlyTake)
+ )
+ ) {
+ moves.push(this.getBasicMove(initSquare, [i, j]));
+ }
+ }
+ return moves;
+ }
+
+ // Modify capturing moves among listed pawn moves
+ addPawnCaptures(moves, byChameleon) {
+ const steps = V.steps[V.ROOK];
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ moves.forEach(m => {
+ if (!!byChameleon && m.start.x != m.end.x && m.start.y != m.end.y)
+ // Chameleon not moving as pawn
+ return;
+ // 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
+ ) {
+ const piece1 = this.getPiece(sq1[0], sq1[1]);
+ if (!byChameleon || piece1 == V.PAWN) {
+ m.vanish.push(
+ new PiPo({
+ x: sq1[0],
+ y: sq1[1],
+ c: oppCol,
+ p: piece1
+ })
+ );
+ }
+ }
+ }
+ }
+ });
+ }
+
+ // "Pincer"
+ getPotentialPawnMoves([x, y]) {
+ let moves = super.getPotentialRookMoves([x, y]);
+ this.addPawnCaptures(moves);
+ return moves;
+ }
+
+ addRookCaptures(moves, byChameleon) {
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ const kp = this.kingPos[color];
+ moves.forEach(m => {
+ // Check piece-king rectangle (if any) corners for enemy pieces
+ if (m.end.x == kp[0] || m.end.y == kp[1]) return; //"flat rectangle"
+ const corner1 = [m.end.x, kp[1]];
+ const corner2 = [kp[0], m.end.y];
+ for (let [i, j] of [corner1, corner2]) {
+ if (this.board[i][j] != V.EMPTY && this.getColor(i, j) == oppCol) {
+ const piece = this.getPiece(i, j);
+ if (!byChameleon || piece == V.ROOK) {
+ m.vanish.push(
+ new PiPo({
+ x: i,
+ y: j,
+ p: piece,
+ c: oppCol
+ })
+ );
+ }
+ }
+ }
+ });
+ }
+
+ // Coordinator
+ getPotentialRookMoves(sq) {
+ let moves = super.getPotentialQueenMoves(sq);
+ this.addRookCaptures(moves);
+ return moves;
+ }
+
+ getKnightCaptures(startSquare, byChameleon) {
+ // Look in every direction for captures
+ const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ let moves = [];
+ const [x, y] = [startSquare[0], startSquare[1]];
+ const piece = this.getPiece(x, y); //might be a chameleon!
+ outerLoop: for (let step of steps) {
+ let [i, j] = [x + step[0], y + step[1]];
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ i += step[0];
+ j += step[1];
+ }
+ if (
+ !V.OnBoard(i, j) ||
+ this.getColor(i, j) == color ||
+ (!!byChameleon && this.getPiece(i, j) != V.KNIGHT)
+ ) {
+ continue;
+ }
+ // last(thing), cur(thing) : stop if "cur" is our color,
+ // or beyond board limits, or if "last" isn't empty and cur neither.
+ // Otherwise, if cur is empty then add move until cur square;
+ // if cur is occupied then stop if !!byChameleon and the square not
+ // occupied by a leaper.
+ let last = [i, j];
+ let cur = [i + step[0], j + step[1]];
+ let vanished = [new PiPo({ x: x, y: y, c: color, p: piece })];
+ while (V.OnBoard(cur[0], cur[1])) {
+ if (this.board[last[0]][last[1]] != V.EMPTY) {
+ const oppPiece = this.getPiece(last[0], last[1]);
+ if (!!byChameleon && oppPiece != V.KNIGHT) continue outerLoop;
+ // Something to eat:
+ vanished.push(
+ new PiPo({ x: last[0], y: last[1], c: oppCol, p: oppPiece })
+ );
+ }
+ if (this.board[cur[0]][cur[1]] != V.EMPTY) {
+ if (
+ this.getColor(cur[0], cur[1]) == color ||
+ this.board[last[0]][last[1]] != V.EMPTY
+ ) {
+ //TODO: redundant test
+ continue outerLoop;
+ }
+ } else {
+ moves.push(
+ new Move({
+ appear: [new PiPo({ x: cur[0], y: cur[1], c: color, p: piece })],
+ vanish: JSON.parse(JSON.stringify(vanished)), //TODO: required?
+ start: { x: x, y: y },
+ end: { x: cur[0], y: cur[1] }
+ })
+ );
+ }
+ last = [last[0] + step[0], last[1] + step[1]];
+ cur = [cur[0] + step[0], cur[1] + step[1]];
+ }
+ }
+ return moves;
+ }
+
+ // Long-leaper
+ getPotentialKnightMoves(sq) {
+ return super.getPotentialQueenMoves(sq).concat(this.getKnightCaptures(sq));
+ }
+
+ // Chameleon
+ getPotentialBishopMoves([x, y]) {
+ let moves = super
+ .getPotentialQueenMoves([x, y])
+ .concat(this.getKnightCaptures([x, y], "asChameleon"))
+ .concat(this.getPotentialGuardMoves([x, y], "asChameleon"))
+ .concat(this.getPotentialMageMoves([x, y], "asChameleon"));
+ // No "king capture" because king cannot remain under check
+ this.addPawnCaptures(moves, "asChameleon");
+ this.addRookCaptures(moves, "asChameleon");
+ this.addQueenCaptures(moves, "asChameleon");
+ // Post-processing: merge similar moves, concatenating vanish arrays
+ let mergedMoves = {};
+ moves.forEach(m => {
+ const key = m.end.x + V.size.x * m.end.y;
+ if (!mergedMoves[key]) mergedMoves[key] = m;
+ else {
+ for (let i = 1; i < m.vanish.length; i++)
+ mergedMoves[key].vanish.push(m.vanish[i]);
+ }
+ });
+ return Object.values(mergedMoves);
+ }
+
+ addQueenCaptures(moves, byChameleon) {
+ if (moves.length == 0) return;
+ const [x, y] = [moves[0].start.x, moves[0].start.y];
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ let capturingDirections = [];
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ adjacentSteps.forEach(step => {
+ 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 &&
+ (!byChameleon || this.getPiece(i, j) == V.QUEEN)
+ ) {
+ capturingDirections.push(step);
+ }
+ });
+ moves.forEach(m => {
+ const step = [
+ m.end.x != x ? (m.end.x - x) / Math.abs(m.end.x - x) : 0,
+ m.end.y != y ? (m.end.y - y) / Math.abs(m.end.y - y) : 0
+ ];
+ // TODO: this test should be done only once per direction
+ if (
+ capturingDirections.some(dir => {
+ return dir[0] == -step[0] && dir[1] == -step[1];
+ })
+ ) {
+ const [i, j] = [x - step[0], y - step[1]];
+ m.vanish.push(
+ new PiPo({
+ x: i,
+ y: j,
+ p: this.getPiece(i, j),
+ c: oppCol
+ })
+ );
+ }
+ });
+ }
+
+ // Withdrawer
+ getPotentialQueenMoves(sq) {
+ let moves = super.getPotentialQueenMoves(sq);
+ this.addQueenCaptures(moves);
+ return moves;
+ }
+
+ getPotentialImmobilizerMoves(sq) {
+ // Immobilizer doesn't capture
+ return super.getPotentialQueenMoves(sq);
+ }
+
+ getPotentialKingMoves(sq) {
+ return this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep");
+ }
+
+ getPotentialGuardMoves(sq, byChameleon) {
+ const onlyTake = !byChameleon ? null : V.GUARD;
+ return (
+ this.getSlideNJumpMoves(
+ sq,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
+ "oneStep",
+ null,
+ onlyTake
+ )
+ );
+ }
+
+ getNextMageSteps(step) {
+ if (step[0] == -1) {
+ if (step[1] == -1) return [[-1, 0], [0, -1]];
+ return [[-1, 0], [0, 1]];
+ }
+ if (step[1] == -1) return [[1, 0], [0, -1]];
+ return [[1, 0], [0, 1]];
+ }
+
+ getPotentialMageMoves([x, y], byChameleon) {
+ const oppCol = V.GetOppCol(this.turn);
+ const onlyTake = !byChameleon ? null : V.MAGE;
+ let moves = [];
+ for (let step of V.steps[V.BISHOP]) {
+ let [i, j] = [x + step[0], y + step[1]];
+ if (!V.OnBoard(i, j)) continue;
+ if (this.board[i][j] != V.EMPTY) {
+ if (
+ this.getColor(i, j) == oppCol &&
+ (!onlyTake || this.getPiece(i, j) == V.MAGE)
+ ) {
+ // Capture
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ }
+ }
+ else {
+ if (!onlyTake) moves.push(this.getBasicMove([x, y], [i, j]));
+ // Continue orthogonally:
+ const stepO = this.getNextMageSteps(step);
+ Array.prototype.push.apply(
+ moves,
+ this.getSlideNJumpMoves([i, j], stepO, null, [x, y], onlyTake)
+ );
+ }
+ }
+ return moves;
+ }
+
+ isAttacked(sq, color) {
+ return (
+ super.isAttacked(sq, color) ||
+ this.isAttackedByGuard(sq, color) ||
+ this.isAttackedByMage(sq, color)
+ );
+ }
+
+ isAttackedByPawn([x, y], color) {
+ // Square (x,y) must be surroundable by two enemy pieces,
+ // and one of them at least should be a pawn (moving).
+ const dirs = [
+ [1, 0],
+ [0, 1]
+ ];
+ const steps = V.steps[V.ROOK];
+ for (let dir of dirs) {
+ const [i1, j1] = [x - dir[0], y - dir[1]]; //"before"
+ const [i2, j2] = [x + dir[0], y + dir[1]]; //"after"
+ if (V.OnBoard(i1, j1) && V.OnBoard(i2, j2)) {
+ if (
+ (
+ this.board[i1][j1] != V.EMPTY &&
+ this.getColor(i1, j1) == color &&
+ this.board[i2][j2] == V.EMPTY
+ )
+ ||
+ (
+ this.board[i2][j2] != V.EMPTY &&
+ this.getColor(i2, j2) == color &&
+ this.board[i1][j1] == V.EMPTY
+ )
+ ) {
+ // Search a movable enemy pawn landing on the empty square
+ for (let step of steps) {
+ let [ii, jj] = this.board[i1][j1] == V.EMPTY ? [i1, j1] : [i2, j2];
+ let [i3, j3] = [ii + step[0], jj + step[1]];
+ while (V.OnBoard(i3, j3) && this.board[i3][j3] == V.EMPTY) {
+ i3 += step[0];
+ j3 += step[1];
+ }
+ if (
+ V.OnBoard(i3, j3) &&
+ this.getColor(i3, j3) == color &&
+ this.getPiece(i3, j3) == V.PAWN &&
+ !this.isImmobilized([i3, j3])
+ ) {
+ return true;
+ }
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ isAttackedByRook([x, y], color) {
+ // King must be on same column or row,
+ // and a rook should be able to reach a capturing square
+ const sameRow = x == this.kingPos[color][0];
+ const sameColumn = y == this.kingPos[color][1];
+ if (sameRow || sameColumn) {
+ // Look for the enemy rook (maximum 1)
+ 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 &&
+ this.getPiece(i, j) == V.ROOK
+ ) {
+ if (this.isImmobilized([i, j]))
+ // Because only one rook:
+ return false;
+ // Can it reach a capturing square? Easy but quite suboptimal way
+ // (TODO: generate all moves (turn is OK))
+ const moves = this.getPotentialMovesFrom([i, j]);
+ for (let move of moves) {
+ if (
+ (sameRow && move.end.y == y) ||
+ (sameColumn && move.end.x == x)
+ ) {
+ return true;
+ }
+ }
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ isAttackedByKnight([x, y], color) {
+ // Square (x,y) must be on same line as a knight,
+ // and there must be empty square(s) behind.
+ const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ outerLoop: for (let step of steps) {
+ const [i0, j0] = [x + step[0], y + step[1]];
+ if (V.OnBoard(i0, j0) && this.board[i0][j0] == V.EMPTY) {
+ // Try in opposite direction:
+ let [i, j] = [x - step[0], y - step[1]];
+ while (V.OnBoard(i, j)) {
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ i -= step[0];
+ j -= step[1];
+ }
+ if (V.OnBoard(i, j)) {
+ if (this.getColor(i, j) == color) {
+ if (
+ this.getPiece(i, j) == V.KNIGHT &&
+ !this.isImmobilized([i, j])
+ ) {
+ return true;
+ }
+ continue outerLoop;
+ }
+ // [else] Our color,
+ // could be captured *if there was an empty space*
+ if (this.board[i + step[0]][j + step[1]] != V.EMPTY)
+ continue outerLoop;
+ i -= step[0];
+ j -= step[1];
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ isAttackedByBishop([x, y], color) {
+ // We cheat a little here: since this function is used exclusively for
+ // the king, it's enough to check the immediate surrounding of the square.
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color &&
+ this.getPiece(i, j) == V.BISHOP &&
+ !this.isImmobilized([i, j])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByQueen([x, y], color) {
+ // Square (x,y) must be adjacent to a queen, and the queen must have
+ // some free space in the opposite direction from (x,y)
+ const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of adjacentSteps) {
+ const sq2 = [x + 2 * step[0], y + 2 * step[1]];
+ if (V.OnBoard(sq2[0], sq2[1]) && this.board[sq2[0]][sq2[1]] == V.EMPTY) {
+ const sq1 = [x + step[0], y + step[1]];
+ if (
+ this.board[sq1[0]][sq1[1]] != V.EMPTY &&
+ this.getColor(sq1[0], sq1[1]) == color &&
+ this.getPiece(sq1[0], sq1[1]) == V.QUEEN &&
+ !this.isImmobilized(sq1)
+ ) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ isAttackedByKing([x, y], color) {
+ for (let step of V.steps[V.KNIGHT]) {
+ let rx = x + step[0],
+ // Circular board for king-knight:
+ ry = (y + step[1]) % V.size.y;
+ if (
+ V.OnBoard(rx, ry) &&
+ this.getPiece(rx, ry) === V.KING &&
+ this.getColor(rx, ry) == color &&
+ !this.isImmobilized([rx, ry])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ isAttackedByGuard(sq, color) {
+ return (
+ super.isAttackedBySlideNJump(
+ sq,
+ color,
+ V.GUARD,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
+ "oneStep"
+ )
+ );
+ }
+
+ getNextMageCheck(step) {
+ if (step[0] == 0) {
+ if (step[1] == 1) return [[1, 1], [-1, 1]];
+ return [[-1, -1], [1, -1]];
+ }
+ if (step[0] == -1) return [[-1, -1], [-1, 1]];
+ return [[1, 1], [1, -1]];
+ }
+
+ isAttackedByMage([x, y], color) {
+ for (let step of V.steps[V.BISHOP]) {
+ const [i, j] = [x + step[0], y + step[1]];
+ if (
+ V.OnBoard(i, j) &&
+ this.board[i][j] != V.EMPTY &&
+ this.getColor(i, j) == color &&
+ this.getPiece(i, j) == V.MAGE
+ ) {
+ return true;
+ }
+ }
+ for (let step of V.steps[V.ROOK]) {
+ let [i, j] = [x + step[0], y + step[1]];
+ const stepM = this.getNextMageCheck(step);
+ while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
+ for (let s of stepM) {
+ const [ii, jj] = [i + s[0], j + s[1]];
+ if (
+ V.OnBoard(ii, jj) &&
+ this.board[ii][jj] != V.EMPTY &&
+ this.getColor(ii, jj) == color &&
+ this.getPiece(ii, jj) == V.MAGE
+ ) {
+ return true;
+ }
+ }
+ i += step[0];
+ j += step[1];
+ }
+ }
+ return false;
+ }
+
+ getCurrentScore() {
+ const color = this.turn;
+ const getScoreLost = () => {
+ // Result if I lose:
+ return color == "w" ? "0-1" : "1-0";
+ };
+ if (!this.atLeastOneMove()) {
+ // No valid move: I lose or draw
+ if (this.underCheck(color)) return getScoreLost();
+ return "1/2";
+ }
+ // I lose also if no pieces left (except king)
+ let piecesLeft = 0;
+ outerLoop: 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 &&
+ this.getPiece(i,j) != V.KING
+ ) {
+ piecesLeft++;
+ }
+ }
+ }
+ if (piecesLeft == 0) return getScoreLost();
+ // Check if my palace is invaded:
+ const pX = (color == 'w' ? 10 : 0);
+ const oppCol = V.GetOppCol(color);
+ if (
+ this.board[pX][3] != V.EMPTY &&
+ this.getColor(pX, 3) == oppCol &&
+ this.board[pX][4] != V.EMPTY &&
+ this.getColor(pX, 4) == oppCol
+ ) {
+ return getScoreLost();
+ }
+ return "*";
+ }
+
+ static GenRandInitFen() {
+ // Always deterministic:
+ return (
+ "xxx2xxx/1g1qk1g1/1bnmrnb1/dppppppd/8/8/8/" +
+ "DPPPPPPD/1BNMRNB1/1G1QK1G1/xxx2xxx w 0"
+ );
+ }
+
+ static get VALUES() {
+ return {
+ p: 1,
+ r: 2,
+ n: 5,
+ b: 4,
+ q: 2,
+ m: 5,
+ g: 7,
+ d: 4,
+ k: 1000
+ };
+ }
+
+ static get SEARCH_DEPTH() {
+ return 2;
+ }
+
+ evalPosition() {
+ let evaluation = 0;
+ for (let i = 0; i < V.size.x; i++) {
+ for (let j = 0; j < V.size.y; j++) {
+ if (![V.EMPTY,V.NOTHING].includes(this.board[i][j])) {
+ const sign = this.getColor(i, j) == "w" ? 1 : -1;
+ evaluation += sign * V.VALUES[this.getPiece(i, j)];
+ }
+ }
+ }
+ return evaluation;
+ }
+
+ getNotation(move) {
+ const initialSquare = V.CoordsToSquare(move.start);
+ const finalSquare = V.CoordsToSquare(move.end);
+ if (move.appear.length == 0)
+ // Suicide 'S'
+ return initialSquare + "S";
+ let notation = undefined;
+ if (move.appear[0].p == V.PAWN) {
+ // Pawn: generally ambiguous short notation, so we use full description
+ notation = "P" + initialSquare + finalSquare;
+ } else if (move.appear[0].p == V.KING)
+ notation = "K" + (move.vanish.length > 1 ? "x" : "") + finalSquare;
+ else notation = move.appear[0].p.toUpperCase() + finalSquare;
+ // Add a capture mark (not describing what is captured...):
+ if (move.vanish.length > 1 && move.appear[0].p != V.KING) notation += "X";
+ return notation;
+ }
+};
projects / vchess.git / blobdiff