-import { randInt } from "@/utils/alea";
-
-export const VariantRules = class BaroqueRules extends ChessRules
-{
- static get HasFlags() { return false; }
-
- static get HasEnpassant() { return false; }
-
- static getPpath(b)
- {
- if (b[1] == "m") //'m' for Immobilizer (I is too similar to 1)
- return "Baroque/" + b;
- return b; //usual piece
- }
-
- static get PIECES()
- {
- return ChessRules.PIECES.concat([V.IMMOBILIZER]);
- }
-
- // 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:
- let num = parseInt(position[i].charAt(j));
- if (!isNaN(num))
- k += (num-1);
- }
- k++;
- }
- }
- }
-
- static get IMMOBILIZER() { return 'm'; }
- // 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);
- const color = this.getColor(x,y);
- const oppCol = V.GetOppCol(color);
- const adjacentSteps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
- outerLoop:
- 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)
- {
- // Moving is impossible only if this immobilizer is not neutralized
- for (let step2 of adjacentSteps)
- {
- const [i2,j2] = [i+step2[0],j+step2[1]];
- if (i2 == x && j2 == y)
- continue; //skip initial piece!
- if (V.OnBoard(i2,j2) && this.board[i2][j2] != V.EMPTY
- && this.getColor(i2,j2) == color)
- {
- if ([V.BISHOP,V.IMMOBILIZER].includes(this.getPiece(i2,j2)))
- return false;
- }
- }
- return true; //immobilizer isn't neutralized
- }
- // Chameleons can't be immobilized twice, because there is only one immobilizer
- if (oppPiece == V.BISHOP && piece == V.IMMOBILIZER)
- return true;
- }
- }
- return false;
- }
-
- getPotentialMovesFrom([x,y])
- {
- // Pre-check: is thing on this square immobilized?
- if (this.isImmobilized([x,y]))
- return [];
- switch (this.getPiece(x,y))
- {
- case V.IMMOBILIZER:
- return this.getPotentialImmobilizerMoves([x,y]);
- default:
- return super.getPotentialMovesFrom([x,y]);
- }
- }
-
- getSlideNJumpMoves([x,y], steps, oneStep)
- {
- const color = this.getColor(x,y);
- const piece = this.getPiece(x,y);
- let moves = [];
- outerLoop:
- for (let step of steps)
- {
- let i = 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];
- j += step[1];
- }
- // Only king can take on occupied square:
- if (piece==V.KING && V.OnBoard(i,j) && this.canTake([x,y], [i,j]))
- moves.push(this.getBasicMove([x,y], [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)
- return; //chameleon not moving as pawn
- // 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;
- }
-
- // Long-leaper
- 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));
- }
-
- getPotentialBishopMoves([x,y])
- {
- let moves = super.getPotentialQueenMoves([x,y])
- .concat(this.getKnightCaptures([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]);
- }
- });
- // Finally return an array
- moves = [];
- Object.keys(mergedMoves).forEach(k => { moves.push(mergedMoves[k]); });
- return moves;
- }
-
- // Withdrawer
- 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
- ];
- // NOTE: includes() and even _.isEqual() functions fail...
- // 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
- }));
- }
- });
- }
-
- 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.ROOK].concat(V.steps[V.BISHOP]), "oneStep");
- }
-
- // isAttacked() is OK because the immobilizer doesn't take
-
- isAttackedByPawn([x,y], colors)
- {
- // 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 && colors.includes(this.getColor(i1,j1))
- && this.board[i2][j2]==V.EMPTY)
- ||
- (this.board[i2][j2]!=V.EMPTY && colors.includes(this.getColor(i2,j2))
- && 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) && colors.includes(this.getColor(i3,j3))
- && this.getPiece(i3,j3) == V.PAWN && !this.isImmobilized([i3,j3]))
- {
- return true;
- }
- }
- }
- }
- }
- return false;
- }
-
- isAttackedByRook([x,y], colors)
- {
- // King must be on same column or row,
- // and a rook should be able to reach a capturing square
- // colors contains only one element, giving the oppCol and thus king position
- const sameRow = (x == this.kingPos[colors[0]][0]);
- const sameColumn = (y == this.kingPos[colors[0]][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 && colors.includes(this.getColor(i,j))
- && this.getPiece(i,j) == V.ROOK)
- {
- if (this.isImmobilized([i,j]))
- return false; //because only one rook
- // 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], colors)
- {
- // 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 (colors.includes(this.getColor(i,j)))
- {
- 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], colors)
- {
- // We cheat a little here: since this function is used exclusively for 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
- && colors.includes(this.getColor(i,j)) && this.getPiece(i,j) == V.BISHOP)
- {
- return true; //bishops are never immobilized
- }
- }
- return false;
- }
-
- isAttackedByQueen([x,y], colors)
- {
- // 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
- && colors.includes(this.getColor(sq1[0],sq1[1]))
- && this.getPiece(sq1[0],sq1[1]) == V.QUEEN
- && !this.isImmobilized(sq1))
- {
- return true;
- }
- }
- }
- return false;
- }
-
- static get VALUES()
- {
- // TODO: totally experimental!
- return {
- 'p': 1,
- 'r': 2,
- 'n': 5,
- 'b': 3,
- 'q': 3,
- 'm': 5,
- 'k': 1000
- };
- }
-
- static get SEARCH_DEPTH() { return 2; } //TODO?
-
- 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 every piece, totally freely
-
- let randIndex = randInt(8);
- const bishop1Pos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- randIndex = randInt(7);
- const bishop2Pos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- randIndex = randInt(6);
- const knight1Pos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- randIndex = randInt(5);
- const knight2Pos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- randIndex = randInt(4);
- const queenPos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- randIndex = randInt(3);
- const kingPos = positions[randIndex];
- positions.splice(randIndex, 1);
-
- randIndex = randInt(2);
- const rookPos = positions[randIndex];
- positions.splice(randIndex, 1);
- const immobilizerPos = positions[0];
-
- pieces[c][bishop1Pos] = 'b';
- pieces[c][bishop2Pos] = 'b';
- pieces[c][knight1Pos] = 'n';
- pieces[c][knight2Pos] = 'n';
- pieces[c][queenPos] = 'q';
- pieces[c][kingPos] = 'k';
- pieces[c][rookPos] = 'r';
- pieces[c][immobilizerPos] = 'm';
- }
- return pieces["b"].join("") +
- "/pppppppp/8/8/8/8/PPPPPPPP/" +
- pieces["w"].join("").toUpperCase() +
- " w 0";
- }
-
- getNotation(move)
- {
- const initialSquare = V.CoordsToSquare(move.start);
- const finalSquare = V.CoordsToSquare(move.end);
- 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;
- if (move.vanish.length > 1 && move.appear[0].p != V.KING)
- notation += "X"; //capture mark (not describing what is captured...)
- return notation;
- }
-}
+import { shuffle } from "@/utils/alea";
+
+export class BaroqueRules extends ChessRules {
+ static get HasFlags() {
+ return false;
+ }
+
+ static get HasEnpassant() {
+ return false;
+ }
+
+ static get PIECES() {
+ return ChessRules.PIECES.concat([V.IMMOBILIZER]);
+ }
+
+ getPpath(b) {
+ if (b[1] == "m")
+ //'m' for Immobilizer (I is too similar to 1)
+ return "Baroque/" + b;
+ return b; //usual piece
+ }
+
+ // 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 IMMOBILIZER() {
+ return "m";
+ }
+ // 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);
+ const color = this.getColor(x, y);
+ const oppCol = V.GetOppCol(color);
+ 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) {
+ // Moving is possible only if this immobilizer is neutralized
+ for (let step2 of adjacentSteps) {
+ const [i2, j2] = [i + step2[0], j + step2[1]];
+ if (i2 == x && j2 == y) continue; //skip initial piece!
+ if (
+ V.OnBoard(i2, j2) &&
+ this.board[i2][j2] != V.EMPTY &&
+ this.getColor(i2, j2) == color
+ ) {
+ if ([V.BISHOP, V.IMMOBILIZER].includes(this.getPiece(i2, j2)))
+ return false;
+ }
+ }
+ return true; //immobilizer isn't neutralized
+ }
+ // Chameleons can't be immobilized twice, because there is only one immobilizer
+ if (oppPiece == V.BISHOP && piece == V.IMMOBILIZER) return true;
+ }
+ }
+ return false;
+ }
+
+ getPotentialMovesFrom([x, y]) {
+ // Pre-check: is thing on this square immobilized?
+ if (this.isImmobilized([x, y])) return [];
+ switch (this.getPiece(x, y)) {
+ case V.IMMOBILIZER:
+ return this.getPotentialImmobilizerMoves([x, y]);
+ default:
+ return super.getPotentialMovesFrom([x, y]);
+ }
+ }
+
+ getSlideNJumpMoves([x, y], steps, oneStep) {
+ const piece = this.getPiece(x, y);
+ let moves = [];
+ outerLoop: for (let step of steps) {
+ let i = 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];
+ j += step[1];
+ }
+ // Only king can take on occupied square:
+ if (piece == V.KING && V.OnBoard(i, j) && this.canTake([x, y], [i, j]))
+ moves.push(this.getBasicMove([x, y], [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) return; //chameleon not moving as pawn
+ // 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"));
+ // 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]);
+ }
+ });
+ // Finally return an array
+ moves = [];
+ Object.keys(mergedMoves).forEach(k => {
+ moves.push(mergedMoves[k]);
+ });
+ return moves;
+ }
+
+ 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
+ ];
+ // NOTE: includes() and even _.isEqual() functions fail...
+ // 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);
+ }
+
+ // isAttacked() is OK because the immobilizer doesn't take
+
+ 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])) return false; //because only one rook
+ // 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
+ ) {
+ return true; //bishops are never immobilized
+ }
+ }
+ 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) {
+ const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
+ for (let step of steps) {
+ let rx = x + step[0],
+ ry = y + step[1];
+ if (
+ V.OnBoard(rx, ry) &&
+ this.getPiece(rx, ry) === V.KING &&
+ this.getColor(rx, ry) == color &&
+ !this.isImmobilized([rx, ry])
+ ) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ static get VALUES() {
+ return {
+ p: 1,
+ r: 2,
+ n: 5,
+ b: 3,
+ q: 3,
+ m: 5,
+ k: 1000
+ };
+ }
+
+ static get SEARCH_DEPTH() {
+ return 2;
+ }
+
+ static GenRandInitFen(randomness) {
+ if (randomness == 0)
+ // Deterministic:
+ return "rnbqkbnrm/pppppppp/8/8/8/8/PPPPPPPP/MNBKQBNR w 0";
+
+ let pieces = { w: new Array(8), b: new Array(8) };
+ // Shuffle pieces on first and last rank
+ for (let c of ["w", "b"]) {
+ if (c == 'b' && randomness == 1) {
+ pieces['b'] = pieces['w'];
+ break;
+ }
+
+ // Get random squares for every piece, totally freely
+ let positions = shuffle(ArrayFun.range(8));
+ const composition = ['r', 'n', 'b', 'q', 'k', 'b', 'n', 'm'];
+ for (let i = 0; i < 8; i++) pieces[c][positions[i]] = composition[i];
+ }
+ return (
+ pieces["b"].join("") +
+ "/pppppppp/8/8/8/8/PPPPPPPP/" +
+ pieces["w"].join("").toUpperCase() +
+ " w 0"
+ );
+ }
+
+ getNotation(move) {
+ const initialSquare = V.CoordsToSquare(move.start);
+ const finalSquare = V.CoordsToSquare(move.end);
+ 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;
+ }
+};