+ return {
+ 's': 'p',
+ 't': 'q',
+ 'u': 'r',
+ 'c': 'b',
+ 'o': 'n',
+ 'l': 'k',
+ };
+ }
+ static get ALICE_CODES()
+ {
+ return {
+ 'p': 's',
+ 'q': 't',
+ 'r': 'u',
+ 'b': 'c',
+ 'n': 'o',
+ 'k': 'l',
+ };
+ }
+
+ static getPpath(b)
+ {
+ return (Object.keys(this.ALICE_PIECES).includes(b[1]) ? "Alice/" : "") + b;
+ }
+
+ static get PIECES() {
+ return ChessRules.PIECES.concat(Object.keys(V.ALICE_PIECES));
+ }
+
+ initVariables(fen)
+ {
+ super.initVariables(fen);
+ const fenParts = fen.split(" ");
+ const position = fenParts[0].split("/");
+ if (this.kingPos["w"][0] < 0 || this.kingPos["b"][0] < 0)
+ {
+ // INIT_COL_XXX won't be used, so no need to set them for Alice kings
+ for (let i=0; i<position.length; i++)
+ {
+ let k = 0; //column index on board
+ for (let j=0; j<position[i].length; j++)
+ {
+ switch (position[i].charAt(j))
+ {
+ case 'l':
+ this.kingPos['b'] = [i,k];
+ break;
+ case 'L':
+ this.kingPos['w'] = [i,k];
+ break;
+ default:
+ let num = parseInt(position[i].charAt(j));
+ if (!isNaN(num))
+ k += (num-1);
+ }
+ k++;
+ }
+ }
+ }
+ }
+
+ // Return the (standard) color+piece notation at a square for a board
+ getSquareOccupation(i, j, mirrorSide)
+ {
+ const piece = this.getPiece(i,j);
+ if (mirrorSide==1 && Object.keys(V.ALICE_CODES).includes(piece))
+ return this.board[i][j];
+ else if (mirrorSide==2 && Object.keys(V.ALICE_PIECES).includes(piece))
+ return this.getColor(i,j) + V.ALICE_PIECES[piece];
+ return "";
+ }
+
+ // Build board of the given (mirror)side
+ getSideBoard(mirrorSide)
+ {
+ // Build corresponding board from complete board
+ let sideBoard = doubleArray(V.size.x, V.size.y, "");
+ for (let i=0; i<V.size.x; i++)
+ {
+ for (let j=0; j<V.size.y; j++)
+ sideBoard[i][j] = this.getSquareOccupation(i, j, mirrorSide);
+ }
+ return sideBoard;
+ }
+
+ // NOTE: castle & enPassant https://www.chessvariants.com/other.dir/alice.html
+ getPotentialMovesFrom([x,y], sideBoard)
+ {
+ const pieces = Object.keys(V.ALICE_CODES);
+ const codes = Object.keys(V.ALICE_PIECES);
+ const mirrorSide = (pieces.includes(this.getPiece(x,y)) ? 1 : 2);
+
+ // Search valid moves on sideBoard
+ let saveBoard = this.board;
+ this.board = sideBoard || this.getSideBoard(mirrorSide);
+ let moves = super.getPotentialMovesFrom([x,y]);
+ this.board = saveBoard;
+
+ // Finally filter impossible moves
+ let res = moves.filter(m => {
+ if (m.appear.length == 2) //castle
+ {
+ // appear[i] must be an empty square on the other board
+ for (let psq of m.appear)
+ {
+ if (this.getSquareOccupation(psq.x,psq.y,3-mirrorSide) != V.EMPTY)
+ return false;
+ }
+ }
+ else if (this.board[m.end.x][m.end.y] != V.EMPTY)
+ {
+ // Attempt to capture
+ const piece = this.getPiece(m.end.x,m.end.y);
+ if ((mirrorSide==1 && codes.includes(piece))
+ || (mirrorSide==2 && pieces.includes(piece)))
+ {
+ return false;
+ }
+ }
+ // If the move is computed on board1, m.appear change for Alice pieces.
+ if (mirrorSide==1)
+ {
+ m.appear.forEach(psq => { //forEach: castling taken into account
+ psq.p = V.ALICE_CODES[psq.p]; //goto board2
+ });
+ }
+ else //move on board2: mark vanishing pieces as Alice
+ {
+ m.vanish.forEach(psq => {
+ psq.p = V.ALICE_CODES[psq.p];
+ });
+ }
+ // Fix en-passant captures
+ if (m.vanish[0].p == V.PAWN && m.vanish.length == 2
+ && this.board[m.end.x][m.end.y] == V.EMPTY)
+ {
+ m.vanish[1].c = this.getOppCol(this.getColor(x,y));
+ // In the special case of en-passant, if
+ // - board1 takes board2 : vanish[1] --> Alice
+ // - board2 takes board1 : vanish[1] --> normal
+ let van = m.vanish[1];
+ if (mirrorSide==1 && codes.includes(this.getPiece(van.x,van.y)))
+ van.p = V.ALICE_CODES[van.p];
+ else if (mirrorSide==2 && pieces.includes(this.getPiece(van.x,van.y)))
+ van.p = V.ALICE_PIECES[van.p];
+ }
+ return true;
+ });
+ return res;
+ }
+
+ filterValid(moves)
+ {
+ if (moves.length == 0)
+ return [];
+ let sideBoard = [this.getSideBoard(1), this.getSideBoard(2)];
+ return moves.filter(m => { return !this.underCheck(m, sideBoard); });
+ }
+
+ getAllValidMoves()
+ {
+ const color = this.turn;
+ const oppCol = this.getOppCol(color);
+ var potentialMoves = [];
+ let sideBoard = [this.getSideBoard(1), this.getSideBoard(2)];
+ for (var i=0; i<V.size.x; i++)
+ {
+ for (var j=0; j<V.size.y; j++)
+ {
+ if (this.board[i][j] != V.EMPTY && this.getColor(i,j) == color)
+ {
+ const mirrorSide =
+ Object.keys(V.ALICE_CODES).includes(this.getPiece(i,j))
+ ? 1
+ : 2;
+ Array.prototype.push.apply(potentialMoves,
+ this.getPotentialMovesFrom([i,j], sideBoard[mirrorSide-1]));
+ }
+ }
+ }
+ return this.filterValid(potentialMoves, sideBoard);
+ }
+
+ // Play on sideboards [TODO: only one sideBoard required]
+ playSide(move, sideBoard)
+ {
+ const pieces = Object.keys(V.ALICE_CODES);
+ move.vanish.forEach(psq => {
+ const mirrorSide = (pieces.includes(psq.p) ? 1 : 2);
+ sideBoard[mirrorSide-1][psq.x][psq.y] = V.EMPTY;
+ });
+ move.appear.forEach(psq => {
+ const mirrorSide = (pieces.includes(psq.p) ? 1 : 2);
+ const piece = (mirrorSide == 1 ? psq.p : V.ALICE_PIECES[psq.p]);
+ sideBoard[mirrorSide-1][psq.x][psq.y] = psq.c + piece;
+ if (piece == V.KING)
+ this.kingPos[psq.c] = [psq.x,psq.y];
+ });
+ }
+
+ // Undo on sideboards
+ undoSide(move, sideBoard)
+ {
+ const pieces = Object.keys(V.ALICE_CODES);
+ move.appear.forEach(psq => {
+ const mirrorSide = (pieces.includes(psq.p) ? 1 : 2);
+ sideBoard[mirrorSide-1][psq.x][psq.y] = V.EMPTY;
+ });
+ move.vanish.forEach(psq => {
+ const mirrorSide = (pieces.includes(psq.p) ? 1 : 2);
+ const piece = (mirrorSide == 1 ? psq.p : V.ALICE_PIECES[psq.p]);
+ sideBoard[mirrorSide-1][psq.x][psq.y] = psq.c + piece;
+ if (piece == V.KING)
+ this.kingPos[psq.c] = [psq.x,psq.y];
+ });
+ }
+
+ underCheck(move, sideBoard) //sideBoard arg always provided
+ {
+ const color = this.turn;
+ this.playSide(move, sideBoard); //no need to track flags
+ const kp = this.kingPos[color];
+ const mirrorSide = (sideBoard[0][kp[0]][kp[1]] != V.EMPTY ? 1 : 2);
+ let saveBoard = this.board;
+ this.board = sideBoard[mirrorSide-1];
+ let res = this.isAttacked(kp, [this.getOppCol(color)]);
+ this.board = saveBoard;
+ this.undoSide(move, sideBoard);
+ return res;
+ }
+
+ getCheckSquares(move)
+ {
+ this.play(move);
+ const color = this.turn; //opponent
+ const pieces = Object.keys(V.ALICE_CODES);
+ const kp = this.kingPos[color];
+ const mirrorSide = (pieces.includes(this.getPiece(kp[0],kp[1])) ? 1 : 2);
+ let sideBoard = this.getSideBoard(mirrorSide);
+ let saveBoard = this.board;
+ this.board = sideBoard;
+ let res = this.isAttacked(this.kingPos[color], [this.getOppCol(color)])
+ ? [ JSON.parse(JSON.stringify(this.kingPos[color])) ]
+ : [ ];
+ this.board = saveBoard;
+ this.undo(move);
+ return res;
+ }
+
+ updateVariables(move)
+ {
+ super.updateVariables(move); //standard king
+ const piece = this.getPiece(move.start.x,move.start.y);
+ const c = this.getColor(move.start.x,move.start.y);
+ // "l" = Alice king
+ if (piece == "l")
+ {
+ this.kingPos[c][0] = move.appear[0].x;
+ this.kingPos[c][1] = move.appear[0].y;
+ this.castleFlags[c] = [false,false];
+ }
+ }
+
+ unupdateVariables(move)
+ {
+ super.unupdateVariables(move);
+ const c = this.getColor(move.start.x,move.start.y);
+ if (this.getPiece(move.start.x,move.start.y) == "l")
+ this.kingPos[c] = [move.start.x, move.start.y];
+ }
+
+ checkGameEnd()
+ {
+ const pieces = Object.keys(V.ALICE_CODES);
+ const color = this.turn;
+ const kp = this.kingPos[color];
+ const mirrorSide = (pieces.includes(this.getPiece(kp[0],kp[1])) ? 1 : 2);
+ let sideBoard = this.getSideBoard(mirrorSide);
+ let saveBoard = this.board;
+ this.board = sideBoard;
+ let res = "*";
+ if (!this.isAttacked(this.kingPos[color], [this.getOppCol(color)]))
+ res = "1/2";
+ else
+ res = (color == "w" ? "0-1" : "1-0");
+ this.board = saveBoard;
+ return res;
+ }
+
+ static get VALUES() {
+ return Object.assign(
+ ChessRules.VALUES,
+ {
+ 's': 1,
+ 'u': 5,
+ 'o': 3,
+ 'c': 3,
+ 't': 9,
+ 'l': 1000,
+ }
+ );
+ }
+
+ getNotation(move)
+ {
+ if (move.appear.length == 2 && move.appear[0].p == V.KING)
+ {
+ if (move.end.y < move.start.y)
+ return "0-0-0";
+ else
+ return "0-0";
+ }
+
+ const finalSquare = String.fromCharCode(97 + move.end.y) + (V.size.x-move.end.x);
+ const piece = this.getPiece(move.start.x, move.start.y);
+
+ const captureMark = (move.vanish.length > move.appear.length ? "x" : "");
+ let pawnMark = "";
+ if (["p","s"].includes(piece) && captureMark.length == 1)
+ pawnMark = String.fromCharCode(97 + move.start.y); //start column
+
+ // Piece or pawn movement
+ let notation = piece.toUpperCase() + pawnMark + captureMark + finalSquare;
+ if (['s','p'].includes(piece) && !['s','p'].includes(move.appear[0].p))
+ {
+ // Promotion
+ notation += "=" + move.appear[0].p.toUpperCase();
+ }
+ return notation;