--- /dev/null
+class AntikingRules extends ChessRules
+{
+ static getPpath(b)
+ {
+ return b[1]=='a' ? "Antiking/"+b : b;
+ }
+
+ static get ANTIKING() { return 'a'; }
+
+ static get PIECES()
+ {
+ return ChessRules.PIECES.concat([V.ANTIKING]);
+ }
+
+ setOtherVariables(fen)
+ {
+ super.setOtherVariables(fen);
+ this.antikingPos = {'w':[-1,-1], 'b':[-1,-1]};
+ const rows = V.ParseFen(fen).position.split("/");
+ for (let i=0; i<rows.length; i++)
+ {
+ let k = 0;
+ for (let j=0; j<rows[i].length; j++)
+ {
+ switch (rows[i].charAt(j))
+ {
+ case 'a':
+ this.antikingPos['b'] = [i,k];
+ break;
+ case 'A':
+ this.antikingPos['w'] = [i,k];
+ break;
+ default:
+ const num = parseInt(rows[i].charAt(j));
+ if (!isNaN(num))
+ k += (num-1);
+ }
+ k++;
+ }
+ }
+ }
+
+ canTake([x1,y1], [x2,y2])
+ {
+ const piece1 = this.getPiece(x1,y1);
+ const piece2 = this.getPiece(x2,y2);
+ const color1 = this.getColor(x1,y1);
+ const color2 = this.getColor(x2,y2);
+ return piece2 != "a" &&
+ ((piece1 != "a" && color1 != color2) || (piece1 == "a" && color1 == color2));
+ }
+
+ getPotentialMovesFrom([x,y])
+ {
+ switch (this.getPiece(x,y))
+ {
+ case V.ANTIKING:
+ return this.getPotentialAntikingMoves([x,y]);
+ default:
+ return super.getPotentialMovesFrom([x,y]);
+ }
+ }
+
+ getPotentialAntikingMoves(sq)
+ {
+ return this.getSlideNJumpMoves(sq,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep");
+ }
+
+ isAttacked(sq, colors)
+ {
+ return (super.isAttacked(sq, colors) || this.isAttackedByAntiking(sq, colors));
+ }
+
+ isAttackedByKing([x,y], colors)
+ {
+ if (this.getPiece(x,y) == V.ANTIKING)
+ return false; //antiking is not attacked by king
+ return this.isAttackedBySlideNJump([x,y], colors, V.KING,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep");
+ }
+
+ isAttackedByAntiking([x,y], colors)
+ {
+ if ([V.KING,V.ANTIKING].includes(this.getPiece(x,y)))
+ return false; //(anti)king is not attacked by antiking
+ return this.isAttackedBySlideNJump([x,y], colors, V.ANTIKING,
+ V.steps[V.ROOK].concat(V.steps[V.BISHOP]), "oneStep");
+ }
+
+ underCheck(color)
+ {
+ const oppCol = V.GetOppCol(color);
+ let res = this.isAttacked(this.kingPos[color], [oppCol])
+ || !this.isAttacked(this.antikingPos[color], [oppCol]);
+ return res;
+ }
+
+ getCheckSquares(color)
+ {
+ let res = super.getCheckSquares(color);
+ if (!this.isAttacked(this.antikingPos[color], [V.GetOppCol(color)]))
+ res.push(JSON.parse(JSON.stringify(this.antikingPos[color])));
+ return res;
+ }
+
+ updateVariables(move)
+ {
+ super.updateVariables(move);
+ const piece = move.vanish[0].p;
+ const c = move.vanish[0].c;
+ // Update antiking position
+ if (piece == V.ANTIKING)
+ {
+ this.antikingPos[c][0] = move.appear[0].x;
+ this.antikingPos[c][1] = move.appear[0].y;
+ }
+ }
+
+ unupdateVariables(move)
+ {
+ super.unupdateVariables(move);
+ const c = move.vanish[0].c;
+ if (move.vanish[0].p == V.ANTIKING)
+ this.antikingPos[c] = [move.start.x, move.start.y];
+ }
+
+ checkGameEnd()
+ {
+ const color = this.turn;
+ const oppCol = V.GetOppCol(color);
+ if (!this.isAttacked(this.kingPos[color], [oppCol])
+ && this.isAttacked(this.antikingPos[color], [oppCol]))
+ {
+ return "1/2";
+ }
+ return color == "w" ? "0-1" : "1-0";
+ }
+
+ static get VALUES() {
+ return Object.assign(
+ ChessRules.VALUES,
+ { 'a': 1000 }
+ );
+ }
+
+ static GenRandInitFen()
+ {
+ let pieces = { "w": new Array(8), "b": new Array(8) };
+ let antikingPos = { "w": -1, "b": -1 };
+ for (let c of ["w","b"])
+ {
+ let positions = _.range(8);
+
+ // Get random squares for bishops, but avoid corners; because,
+ // if an antiking blocks a cornered bishop, it can never be checkmated
+ let randIndex = 2 * _.random(1,3);
+ const bishop1Pos = positions[randIndex];
+ let randIndex_tmp = 2 * _.random(2) + 1;
+ const bishop2Pos = positions[randIndex_tmp];
+ positions.splice(Math.max(randIndex,randIndex_tmp), 1);
+ positions.splice(Math.min(randIndex,randIndex_tmp), 1);
+
+ randIndex = _.random(5);
+ const knight1Pos = positions[randIndex];
+ positions.splice(randIndex, 1);
+ randIndex = _.random(4);
+ const knight2Pos = positions[randIndex];
+ positions.splice(randIndex, 1);
+
+ randIndex = _.random(3);
+ const queenPos = positions[randIndex];
+ positions.splice(randIndex, 1);
+
+ const rook1Pos = positions[0];
+ const kingPos = positions[1];
+ const rook2Pos = positions[2];
+
+ // Random squares for antikings
+ antikingPos[c] = _.random(7);
+
+ 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';
+ }
+ const ranks23_black = "pppppppp/" + (antikingPos["w"]>0?antikingPos["w"]:"")
+ + "A" + (antikingPos["w"]<7?7-antikingPos["w"]:"");
+ const ranks23_white = (antikingPos["b"]>0?antikingPos["b"]:"") + "a"
+ + (antikingPos["b"]<7?7-antikingPos["b"]:"") + "/PPPPPPPP";
+ return pieces["b"].join("") + "/" + ranks23_black +
+ "/8/8/" +
+ ranks23_white + "/" + pieces["w"].join("").toUpperCase() +
+ " w 1111 -";
+ }
+}