import { ChessRules } from "@/base_rules";
import { randInt } from "@/utils/alea";
-export const VariantRules = class MarseilleRules extends ChessRules
-{
- static IsGoodEnpassant(enpassant)
- {
- if (enpassant != "-")
- {
+export const VariantRules = class MarseilleRules extends ChessRules {
+ static IsGoodEnpassant(enpassant) {
+ if (enpassant != "-") {
const squares = enpassant.split(",");
- if (squares.length > 2)
- return false;
- for (let sq of squares)
- {
+ if (squares.length > 2) return false;
+ for (let sq of squares) {
const ep = V.SquareToCoords(sq);
- if (isNaN(ep.x) || !V.OnBoard(ep))
- return false;
+ if (isNaN(ep.x) || !V.OnBoard(ep)) return false;
}
}
return true;
}
- getTurnFen()
- {
+ getTurnFen() {
return this.turn + this.subTurn;
}
// There may be 2 enPassant squares (if 2 pawns jump 2 squares in same turn)
- getEnpassantFen()
- {
+ getEnpassantFen() {
const L = this.epSquares.length;
- if (this.epSquares[L-1].every(epsq => epsq === undefined))
- return "-"; //no en-passant
+ if (this.epSquares[L - 1].every(epsq => epsq === undefined)) return "-"; //no en-passant
let res = "";
- this.epSquares[L-1].forEach(epsq => {
- if (!!epsq)
- res += V.CoordsToSquare(epsq) + ",";
+ this.epSquares[L - 1].forEach(epsq => {
+ if (epsq) res += V.CoordsToSquare(epsq) + ",";
});
- return res.slice(0,-1); //remove last comma
+ return res.slice(0, -1); //remove last comma
}
- setOtherVariables(fen)
- {
+ setOtherVariables(fen) {
const parsedFen = V.ParseFen(fen);
this.setFlags(parsedFen.flags);
- if (parsedFen.enpassant == "-")
- this.epSquares = [ [undefined] ];
- else
- {
+ if (parsedFen.enpassant == "-") this.epSquares = [[undefined]];
+ else {
let res = [];
const squares = parsedFen.enpassant.split(",");
- for (let sq of squares)
- res.push(V.SquareToCoords(sq));
- this.epSquares = [ res ];
+ for (let sq of squares) res.push(V.SquareToCoords(sq));
+ this.epSquares = [res];
}
this.scanKingsRooks(fen);
// Extract subTurn from turn indicator: "w" (first move), or
// "w1" or "w2" white subturn 1 or 2, and same for black
const fullTurn = V.ParseFen(fen).turn;
this.turn = fullTurn[0];
- this.subTurn = (fullTurn[1] || 0); //"w0" = special code for first move in game
+ this.subTurn = fullTurn[1] || 0; //"w0" = special code for first move in game
}
- getPotentialPawnMoves([x,y])
- {
+ getPotentialPawnMoves([x, y]) {
const color = this.turn;
let moves = [];
- const [sizeX,sizeY] = [V.size.x,V.size.y];
- const shiftX = (color == "w" ? -1 : 1);
- const firstRank = (color == 'w' ? sizeX-1 : 0);
- const startRank = (color == "w" ? sizeX-2 : 1);
- const lastRank = (color == "w" ? 0 : sizeX-1);
- const finalPieces = x + shiftX == lastRank
- ? [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN]
- : [V.PAWN];
+ const [sizeX, sizeY] = [V.size.x, V.size.y];
+ const shiftX = color == "w" ? -1 : 1;
+ const firstRank = color == "w" ? sizeX - 1 : 0;
+ const startRank = color == "w" ? sizeX - 2 : 1;
+ const lastRank = color == "w" ? 0 : sizeX - 1;
+ const finalPieces =
+ x + shiftX == lastRank ? [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN] : [V.PAWN];
// One square forward
- if (this.board[x+shiftX][y] == V.EMPTY)
- {
- for (let piece of finalPieces)
- {
- moves.push(this.getBasicMove([x,y], [x+shiftX,y],
- {c:color,p:piece}));
+ if (this.board[x + shiftX][y] == V.EMPTY) {
+ for (let piece of finalPieces) {
+ moves.push(
+ this.getBasicMove([x, y], [x + shiftX, y], { c: color, p: piece })
+ );
}
// Next condition because pawns on 1st rank can generally jump
- if ([startRank,firstRank].includes(x)
- && this.board[x+2*shiftX][y] == V.EMPTY)
- {
+ if (
+ [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]));
+ 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}));
+ 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
+ })
+ );
}
}
}
// OK on subturn 2 only if enPassant was played at subturn 1
// (and if there are two e.p. squares available).
const Lep = this.epSquares.length;
- const epSquares = this.epSquares[Lep-1]; //always at least one element
+ const epSquares = this.epSquares[Lep - 1]; //always at least one element
let epSqs = [];
epSquares.forEach(sq => {
- if (!!sq)
- epSqs.push(sq);
+ if (sq) epSqs.push(sq);
});
- if (epSqs.length == 0)
- return moves;
+ if (epSqs.length == 0) return moves;
const oppCol = V.GetOppCol(color);
- for (let sq of epSqs)
- {
- if (this.subTurn == 1 || (epSqs.length == 2 &&
- // Was this en-passant capture already played at subturn 1 ?
- // (Or maybe the opponent filled the en-passant square with a piece)
- this.board[epSqs[0].x][epSqs[0].y] != V.EMPTY))
- {
- if (sq.x == x+shiftX && Math.abs(sq.y - y) == 1
+ for (let sq of epSqs) {
+ if (
+ this.subTurn == 1 ||
+ (epSqs.length == 2 &&
+ // Was this en-passant capture already played at subturn 1 ?
+ // (Or maybe the opponent filled the en-passant square with a piece)
+ this.board[epSqs[0].x][epSqs[0].y] != V.EMPTY)
+ ) {
+ if (
+ sq.x == x + shiftX &&
+ Math.abs(sq.y - y) == 1 &&
// Add condition "enemy pawn must be present"
- && this.getPiece(x,sq.y) == V.PAWN && this.getColor(x,sq.y) == oppCol)
- {
- let epMove = this.getBasicMove([x,y], [sq.x,sq.y]);
+ this.getPiece(x, sq.y) == V.PAWN &&
+ this.getColor(x, sq.y) == oppCol
+ ) {
+ let epMove = this.getBasicMove([x, y], [sq.x, sq.y]);
epMove.vanish.push({
x: x,
y: sq.y,
- p: 'p',
+ p: "p",
c: oppCol
});
moves.push(epMove);
return moves;
}
- play(move)
- {
+ play(move) {
move.flags = JSON.stringify(this.aggregateFlags());
move.turn = this.turn + this.subTurn;
V.PlayOnBoard(this.board, move);
const epSq = this.getEpSquare(move);
- if (this.subTurn == 0) //first move in game
- {
+ if (this.subTurn == 0) {
+ //first move in game
this.turn = "b";
this.subTurn = 1;
this.epSquares.push([epSq]);
}
// Does this move give check on subturn 1? If yes, skip subturn 2
- else if (this.subTurn==1 && this.underCheck(V.GetOppCol(this.turn)))
- {
+ else if (this.subTurn == 1 && this.underCheck(V.GetOppCol(this.turn))) {
this.turn = V.GetOppCol(this.turn);
this.epSquares.push([epSq]);
move.checkOnSubturn1 = true;
- }
- else
- {
- if (this.subTurn == 2)
- {
+ } else {
+ if (this.subTurn == 2) {
this.turn = V.GetOppCol(this.turn);
- let lastEpsq = this.epSquares[this.epSquares.length-1];
+ let lastEpsq = this.epSquares[this.epSquares.length - 1];
lastEpsq.push(epSq);
- }
- else
- this.epSquares.push([epSq]);
+ } else this.epSquares.push([epSq]);
this.subTurn = 3 - this.subTurn;
}
this.updateVariables(move);
}
- undo(move)
- {
+ undo(move) {
this.disaggregateFlags(JSON.parse(move.flags));
V.UndoOnBoard(this.board, move);
- if (move.turn[1] == '0' || move.checkOnSubturn1 || this.subTurn == 2)
+ if (move.turn[1] == "0" || move.checkOnSubturn1 || this.subTurn == 2)
this.epSquares.pop();
- else //this.subTurn == 1
- {
- let lastEpsq = this.epSquares[this.epSquares.length-1];
+ //this.subTurn == 1
+ else {
+ let lastEpsq = this.epSquares[this.epSquares.length - 1];
lastEpsq.pop();
}
this.turn = move.turn[0];
// NOTE: GenRandInitFen() is OK,
// since at first move turn indicator is just "w"
- static get VALUES()
- {
+ static get VALUES() {
return {
- 'p': 1,
- 'r': 5,
- 'n': 3,
- 'b': 3,
- 'q': 7, //slightly less than in orthodox game
- 'k': 1000
+ p: 1,
+ r: 5,
+ n: 3,
+ b: 3,
+ q: 7, //slightly less than in orthodox game
+ k: 1000
};
}
// No alpha-beta here, just adapted min-max at depth 2(+1)
- getComputerMove()
- {
- if (this.subTurn == 2)
- return null; //TODO: imperfect interface setup
+ getComputerMove() {
+ if (this.subTurn == 2) return null; //TODO: imperfect interface setup
const maxeval = V.INFINITY;
const color = this.turn;
// Search best (half) move for opponent turn
const getBestMoveEval = () => {
- const turnBefore = this.turn + this.subTurn;
let score = this.getCurrentScore();
- if (score != "*")
- {
- if (score == "1/2")
- return 0;
+ if (score != "*") {
+ if (score == "1/2") return 0;
return maxeval * (score == "1-0" ? 1 : -1);
}
let moves = this.getAllValidMoves();
- let res = (oppCol == "w" ? -maxeval : maxeval);
- for (let m of moves)
- {
+ let res = oppCol == "w" ? -maxeval : maxeval;
+ for (let m of moves) {
this.play(m);
score = this.getCurrentScore();
// Now turn is oppCol,2 if m doesn't give check
// Otherwise it's color,1. In both cases the next test makes sense
- if (score != "*")
- {
+ if (score != "*") {
if (score == "1/2")
- res = (oppCol == "w" ? Math.max(res, 0) : Math.min(res, 0));
- else
- {
+ res = oppCol == "w" ? Math.max(res, 0) : Math.min(res, 0);
+ else {
// Found a mate
this.undo(m);
return maxeval * (score == "1-0" ? 1 : -1);
}
}
const evalPos = this.evalPosition();
- res = (oppCol == "w" ? Math.max(res, evalPos) : Math.min(res, evalPos));
+ res = oppCol == "w" ? Math.max(res, evalPos) : Math.min(res, evalPos);
this.undo(m);
}
return res;
let moves11 = this.getAllValidMoves();
let doubleMoves = [];
// Rank moves using a min-max at depth 2
- for (let i=0; i<moves11.length; i++)
- {
+ for (let i = 0; i < moves11.length; i++) {
this.play(moves11[i]);
- if (this.turn != color)
- {
+ if (this.turn != color) {
// We gave check with last move: search the best opponent move
- doubleMoves.push({moves:[moves11[i]], eval:getBestMoveEval()});
- }
- else
- {
+ doubleMoves.push({ moves: [moves11[i]], eval: getBestMoveEval() });
+ } else {
let moves12 = this.getAllValidMoves();
- for (let j=0; j<moves12.length; j++)
- {
+ for (let j = 0; j < moves12.length; j++) {
this.play(moves12[j]);
doubleMoves.push({
- moves:[moves11[i],moves12[j]],
- eval:getBestMoveEval()});
+ moves: [moves11[i], moves12[j]],
+ eval: getBestMoveEval()
+ });
this.undo(moves12[j]);
}
}
this.undo(moves11[i]);
}
- doubleMoves.sort( (a,b) => {
- return (color=="w" ? 1 : -1) * (b.eval - a.eval); });
+ 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++)
- {
+ 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];
+ if (selected.length == 1) return selected[0];
return selected;
}
-}
+};
projects / vchess.git / blobdiff