import { ChessRules } from "@/base_rules";
-import { randInt } from "@/utils/alea";
export class Doublemove1Rules extends ChessRules {
static IsGoodEnpassant(enpassant) {
play(move) {
move.flags = JSON.stringify(this.aggregateFlags());
- move.turn = this.turn + this.subTurn;
+ move.turn = [this.turn, this.subTurn];
V.PlayOnBoard(this.board, move);
const epSq = this.getEpSquare(move);
if (this.movesCount == 0) {
this.epSquares.push([epSq]);
this.movesCount = 1;
}
- // Does this move give check on subturn 1? If yes, skip subturn 2
- else if (this.subTurn == 1 && this.underCheck(V.GetOppCol(this.turn))) {
+ // Does this move give check on subturn 1 or reach stalemate?
+ // If yes, skip subturn 2
+ else if (
+ this.subTurn == 1 &&
+ (
+ this.underCheck(V.GetOppCol(this.turn)) ||
+ !this.atLeastOneMove()
+ )
+ ) {
this.turn = V.GetOppCol(this.turn);
this.epSquares.push([epSq]);
move.checkOnSubturn1 = true;
this.movesCount++;
- } else {
+ }
+ else {
if (this.subTurn == 2) {
this.turn = V.GetOppCol(this.turn);
let lastEpsq = this.epSquares[this.epSquares.length - 1];
lastEpsq.push(epSq);
- } else {
+ }
+ else {
this.epSquares.push([epSq]);
this.movesCount++;
}
}
postPlay(move) {
- const c = move.turn.charAt(0);
+ const c = move.turn[0];
const piece = move.vanish[0].p;
const firstRank = c == "w" ? V.size.x - 1 : 0;
- if (piece == V.KING && move.appear.length > 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];
) {
const flagIdx = (move.start.y == this.castleFlags[c][0] ? 0 : 1);
this.castleFlags[c][flagIdx] = V.size.y;
- } else if (
+ }
+ if (
move.end.x == oppFirstRank && //we took opponent rook?
this.castleFlags[oppCol].includes(move.end.y)
) {
this.epSquares.pop();
// Moves counter was just incremented:
this.movesCount--;
- } else {
+ }
+ else {
// Undo the second half of a move
let lastEpsq = this.epSquares[this.epSquares.length - 1];
lastEpsq.pop();
}
this.turn = move.turn[0];
- this.subTurn = parseInt(move.turn[1]);
+ this.subTurn = move.turn[1];
super.postUndo(move);
}
};
const moves11 = this.getAllValidMoves();
- let doubleMoves = [];
+ let doubleMove = null;
+ let bestEval = Number.POSITIVE_INFINITY * (color == 'w' ? -1 : 1);
// Rank moves using a min-max at depth 2
for (let i = 0; i < moves11.length; i++) {
this.play(moves11[i]);
if (this.turn != color) {
// We gave check with last move: search the best opponent move
- doubleMoves.push({ moves: [moves11[i]], eval: getBestMoveEval() });
+ const evalM = getBestMoveEval() + 0.05 - Math.random() / 10;
+ if (
+ (color == 'w' && evalM > bestEval) ||
+ (color == 'b' && evalM < bestEval)
+ ) {
+ doubleMove = moves11[i];
+ bestEval = evalM;
+ }
}
else {
let moves12 = this.getAllValidMoves();
for (let j = 0; j < moves12.length; j++) {
this.play(moves12[j]);
- doubleMoves.push({
- moves: [moves11[i], moves12[j]],
- eval: getBestMoveEval() + 0.05 - Math.random() / 10
- });
+ const evalM = getBestMoveEval() + 0.05 - Math.random() / 10
+ if (
+ (color == 'w' && evalM > bestEval) ||
+ (color == 'b' && evalM < bestEval)
+ ) {
+ doubleMove = [moves11[i], moves12[j]];
+ bestEval = evalM;
+ }
this.undo(moves12[j]);
}
}
this.undo(moves11[i]);
}
-
- // TODO: array + sort + candidates logic not required when adding small
- // fluctuations to the eval function (could also be generalized).
- doubleMoves.sort((a, b) => {
- return (color == "w" ? 1 : -1) * (b.eval - a.eval);
- });
- let candidates = [0]; //indices of candidates moves
- for (
- let i = 1;
- i < doubleMoves.length && doubleMoves[i].eval == doubleMoves[0].eval;
- i++
- ) {
- candidates.push(i);
- }
- const selected = doubleMoves[randInt(candidates.length)].moves;
- if (selected.length == 1) return selected[0];
- return selected;
+ return doubleMove;
}
};