import { ChessRules, PiPo, Move } from "@/base_rules";
import { ArrayFun } from "@/utils/array";
-import { randInt, shuffle } from "@/utils/alea";
+import { shuffle } from "@/utils/alea";
-export const VariantRules = class CircularRules extends ChessRules {
- static get HasFlags() {
+export class CircularRules extends ChessRules {
+
+ static get HasCastle() {
return false;
}
return false;
}
- // TODO: CanFlip --> also for racing kings (answer is false)
+ static get CanFlip() {
+ return false;
+ }
+
+ setFlags(fenflags) {
+ this.pawnFlags = {
+ w: [...Array(8).fill(true)], //pawns can move 2 squares?
+ b: [...Array(8).fill(true)]
+ };
+ for (let c of ["w", "b"]) {
+ for (let i = 0; i < 8; i++)
+ this.pawnFlags[c][i] = fenflags.charAt((c == "w" ? 0 : 8) + i) == "1";
+ }
+ }
+
+ aggregateFlags() {
+ return this.pawnFlags;
+ }
+
+ disaggregateFlags(flags) {
+ this.pawnFlags = flags;
+ }
+
+ static GenRandInitFen(options) {
+ if (options.randomness == 0) {
+ return "8/8/pppppppp/rnbqkbnr/8/8/PPPPPPPP/RNBQKBNR " +
+ "w 0 1111111111111111";
+ }
- // TODO: shuffle on 1st and 5th ranks
- static GenRandInitFen() {
let pieces = { w: new Array(8), b: new Array(8) };
// Shuffle pieces on first and last rank
for (let c of ["w", "b"]) {
- let positions = ArrayFun.range(8);
-
- // Get random squares for bishops
- let randIndex = 2 * randInt(4);
- const bishop1Pos = positions[randIndex];
- // The second bishop must be on a square of different color
- let randIndex_tmp = 2 * randInt(4) + 1;
- const bishop2Pos = positions[randIndex_tmp];
- // Remove chosen squares
- positions.splice(Math.max(randIndex, randIndex_tmp), 1);
- positions.splice(Math.min(randIndex, randIndex_tmp), 1);
-
- // Get random squares for knights
- randIndex = randInt(6);
- const knight1Pos = positions[randIndex];
- positions.splice(randIndex, 1);
- randIndex = randInt(5);
- const knight2Pos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- // Get random square for queen
- randIndex = randInt(4);
- const queenPos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- // Rooks and king positions are now fixed,
- // because of the ordering rook-king-rook
- const rook1Pos = positions[0];
- const kingPos = positions[1];
- const rook2Pos = positions[2];
-
- // Finally put the shuffled pieces in the board array
- pieces[c][rook1Pos] = "r";
- pieces[c][knight1Pos] = "n";
- pieces[c][bishop1Pos] = "b";
- pieces[c][queenPos] = "q";
- pieces[c][kingPos] = "k";
- pieces[c][bishop2Pos] = "b";
- pieces[c][knight2Pos] = "n";
- pieces[c][rook2Pos] = "r";
+ if (c == 'b' && options.randomness == 1) {
+ pieces['b'] = pieces['w'];
+ break;
+ }
+
+ // Get random squares for every piece, totally freely
+ let positions = shuffle(ArrayFun.range(8));
+ const composition = ['b', 'b', 'r', 'r', 'n', 'n', 'k', 'q'];
+ const rem2 = positions[0] % 2;
+ if (rem2 == positions[1] % 2) {
+ // Fix bishops (on different colors)
+ for (let i=2; i<8; i++) {
+ if (positions[i] % 2 != rem2) {
+ [positions[1], positions[i]] = [positions[i], positions[1]];
+ break;
+ }
+ }
+ }
+ for (let i = 0; i < 8; i++) pieces[c][positions[i]] = composition[i];
}
return (
+ "8/8/pppppppp/" +
pieces["b"].join("") +
- "/pppppppp/8/8/8/8/PPPPPPPP/" +
+ "/8/8/PPPPPPPP/" +
pieces["w"].join("").toUpperCase() +
- " w 0"
+ // 16 flags: can pawns advance 2 squares?
+ " w 0 1111111111111111"
);
}
- // TODO: adapt this for a circular board
+ // Output basically x % 8 (circular board)
+ static ComputeX(x) {
+ let res = x % V.size.x;
+ if (res < 0)
+ res += V.size.x;
+ return res;
+ }
+
getSlideNJumpMoves([x, y], steps, oneStep) {
let moves = [];
+ // Don't add move twice when running on an infinite file:
+ let infiniteSteps = {};
outerLoop: for (let step of steps) {
- let i = x + step[0];
+ if (!!infiniteSteps[(-step[0]) + "." + (-step[1])]) continue;
+ let i = V.ComputeX(x + step[0]);
let j = y + step[1];
while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
moves.push(this.getBasicMove([x, y], [i, j]));
- if (oneStep !== undefined) continue outerLoop;
- i += step[0];
+ if (oneStep) continue outerLoop;
+ i = V.ComputeX(i + step[0]);
j += step[1];
}
- if (V.OnBoard(i, j) && this.canTake([x, y], [i, j]))
- moves.push(this.getBasicMove([x, y], [i, j]));
+ if (V.OnBoard(i, j)) {
+ if (i == x && j == y)
+ // Looped back onto initial square
+ infiniteSteps[step[0] + "." + step[1]] = true;
+ else if (this.canTake([x, y], [i, j]))
+ moves.push(this.getBasicMove([x, y], [i, j]));
+ }
}
return moves;
}
- // TODO: adapt: all pawns go in thz same direction!
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 pawnColor = this.getColor(x, y); //can be different for checkered
-
- // NOTE: next condition is generally true (no pawn on last rank)
- if (x + shiftX >= 0 && x + shiftX < sizeX) {
- 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: pawnColor,
- 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
- ) {
- // Two squares jump
- moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y]));
- }
+ // All pawns go in the same direction!
+ const shiftX = -1;
+ const startRank = color == "w" ? sizeX - 2 : 2;
+
+ // One square forward
+ const nextRow = V.ComputeX(x + shiftX);
+ if (this.board[nextRow][y] == V.EMPTY) {
+ moves.push(this.getBasicMove([x, y], [nextRow, y]));
+ if (
+ x == startRank &&
+ this.pawnFlags[color][y] &&
+ 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: pawnColor,
- p: piece
- })
- );
- }
- }
+ }
+ // Captures
+ for (let shiftY of [-1, 1]) {
+ if (
+ y + shiftY >= 0 &&
+ y + shiftY < sizeY &&
+ this.board[nextRow][y + shiftY] != V.EMPTY &&
+ this.canTake([x, y], [nextRow, y + shiftY])
+ ) {
+ moves.push(this.getBasicMove([x, y], [nextRow, y + shiftY]));
}
}
return moves;
}
- // What are the king moves from square x,y ?
- getPotentialKingMoves(sq) {
- return this.getSlideNJumpMoves(
- sq,
- V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
- "oneStep"
- );
+ filterValid(moves) {
+ const filteredMoves = super.filterValid(moves);
+ // If at least one full move made, everything is allowed:
+ if (this.movesCount >= 2) return filteredMoves;
+ // Else, forbid check:
+ const oppCol = V.GetOppCol(this.turn);
+ return filteredMoves.filter(m => {
+ this.play(m);
+ const res = !this.underCheck(oppCol);
+ this.undo(m);
+ return res;
+ });
}
- // TODO: check boundaries here as well
- isAttackedByPawn([x, y], colors) {
- for (let c of colors) {
- let pawnShift = c == "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) == c
- ) {
- return true;
- }
- }
+ isAttackedByPawn([x, y], color) {
+ // pawn shift is always 1 (all pawns go the same way)
+ const attackerRow = V.ComputeX(x + 1);
+ for (let i of [-1, 1]) {
+ if (
+ y + i >= 0 &&
+ y + i < V.size.y &&
+ this.getPiece(attackerRow, y + i) == V.PAWN &&
+ this.getColor(attackerRow, y + i) == color
+ ) {
+ return true;
}
}
return false;
}
- // TODO: adapt this function
- isAttackedBySlideNJump([x, y], colors, piece, steps, oneStep) {
+ isAttackedBySlideNJump([x, y], color, piece, steps, oneStep) {
for (let step of steps) {
- let rx = x + step[0],
+ let rx = V.ComputeX(x + step[0]),
ry = y + step[1];
while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
- rx += step[0];
+ rx = V.ComputeX(rx + step[0]);
ry += step[1];
}
if (
V.OnBoard(rx, ry) &&
- this.getPiece(rx, ry) === piece &&
- colors.includes(this.getColor(rx, ry))
+ this.getPiece(rx, ry) == piece &&
+ this.getColor(rx, ry) == color
) {
return true;
}
}
return false;
}
+
+ getFlagsFen() {
+ // Return pawns flags
+ let flags = "";
+ for (let c of ["w", "b"]) {
+ for (let i = 0; i < 8; i++) flags += this.pawnFlags[c][i] ? "1" : "0";
+ }
+ return flags;
+ }
+
+ postPlay(move) {
+ super.postPlay(move);
+ const c = move.vanish[0].c;
+ const secondRank = { "w": 6, "b": 2 };
+ if (move.vanish[0].p == V.PAWN && secondRank[c] == move.start.x)
+ // This move turns off a 2-squares pawn flag
+ this.pawnFlags[c][move.start.y] = false;
+ }
+
+ static get VALUES() {
+ return {
+ p: 1,
+ r: 5,
+ n: 3,
+ b: 4,
+ q: 10,
+ k: 1000
+ };
+ }
+
+ static get SEARCH_DEPTH() {
+ return 2;
+ }
+
};