-class CheckeredRules extends ChessRules
+import { ChessRules } from "@/base_rules";
+
+export const VariantRules = class CheckeredRules extends ChessRules
{
- static getPpath(b)
- {
- return b[0]=='c' ? "Checkered/"+b : b;
- }
-
- static board2fen(b)
- {
- const checkered_codes = {
- 'p': 's',
- 'q': 't',
- 'r': 'u',
- 'b': 'c',
- 'n': 'o',
- };
- if (b[0]=="c")
- return checkered_codes[b[1]];
- return ChessRules.board2fen(b);
- }
-
- static fen2board(f)
- {
- // Tolerate upper-case versions of checkered pieces (why not?)
- const checkered_pieces = {
- 's': 'p',
- 'S': 'p',
- 't': 'q',
- 'T': 'q',
- 'u': 'r',
- 'U': 'r',
- 'c': 'b',
- 'C': 'b',
- 'o': 'n',
- 'O': 'n',
- };
- if (Object.keys(checkered_pieces).includes(f))
- return 'c'+checkered_pieces[f];
- return ChessRules.fen2board(f);
- }
-
- static get PIECES()
- {
- return ChessRules.PIECES.concat(['s','t','u','c','o']);
- }
-
- static IsGoodFlags(flags)
- {
- // 4 for castle + 16 for pawns
- return !!flags.match(/^[01]{20,20}$/);
- }
-
- setFlags(fenflags)
- {
- super.setFlags(fenflags); //castleFlags
- this.pawnFlags =
- {
- "w": [...Array(8).fill(true)], //pawns can move 2 squares?
- "b": [...Array(8).fill(true)],
- };
- if (!fenflags)
- return;
- const flags = fenflags.substr(4); //skip first 4 digits, for castle
- for (let c of ['w','b'])
- {
- for (let i=0; i<8; i++)
- this.pawnFlags[c][i] = (flags.charAt((c=='w'?0:8)+i) == '1');
- }
- }
-
- aggregateFlags()
- {
- return [this.castleFlags, this.pawnFlags];
- }
-
- disaggregateFlags(flags)
- {
- this.castleFlags = flags[0];
- this.pawnFlags = flags[1];
- }
-
- canTake([x1,y1], [x2,y2])
- {
- const color1 = this.getColor(x1,y1);
- const color2 = this.getColor(x2,y2);
- // Checkered aren't captured
- return color1 != color2 && color2 != 'c' && (color1 != 'c' || color2 != this.turn);
- }
-
- // Post-processing: apply "checkerization" of standard moves
- getPotentialMovesFrom([x,y])
- {
- let standardMoves = super.getPotentialMovesFrom([x,y]);
- const lastRank = this.turn == "w" ? 0 : 7;
- if (this.getPiece(x,y) == V.KING)
- return standardMoves; //king has to be treated differently (for castles)
- let moves = [];
- standardMoves.forEach(m => {
- if (m.vanish[0].p == V.PAWN)
- {
- if (Math.abs(m.end.x-m.start.x)==2 && !this.pawnFlags[this.turn][m.start.y])
- return; //skip forbidden 2-squares jumps
- if (this.board[m.end.x][m.end.y] == V.EMPTY && m.vanish.length==2
- && this.getColor(m.start.x,m.start.y) == 'c')
- {
- return; //checkered pawns cannot take en-passant
- }
- }
- if (m.vanish.length == 1)
- moves.push(m); //no capture
- else
- {
- // A capture occured (m.vanish.length == 2)
- m.appear[0].c = "c";
- moves.push(m);
- if (m.appear[0].p != m.vanish[1].p //avoid promotions (already treated):
- && (m.vanish[0].p != V.PAWN || m.end.x != lastRank))
- {
- // Add transformation into captured piece
- let m2 = JSON.parse(JSON.stringify(m));
- m2.appear[0].p = m.vanish[1].p;
- moves.push(m2);
- }
- }
- });
- return moves;
- }
-
- canIplay(side, [x,y])
- {
- return (side == this.turn && [side,'c'].includes(this.getColor(x,y)));
- }
-
- // Does m2 un-do m1 ? (to disallow undoing checkered moves)
- oppositeMoves(m1, m2)
- {
- return m1.appear.length == 1 && m2.appear.length == 1
- && m1.vanish.length == 1 && m2.vanish.length == 1
- && m1.start.x == m2.end.x && m1.end.x == m2.start.x
- && m1.start.y == m2.end.y && m1.end.y == m2.start.y
- && m1.appear[0].c == m2.vanish[0].c && m1.appear[0].p == m2.vanish[0].p
- && m1.vanish[0].c == m2.appear[0].c && m1.vanish[0].p == m2.appear[0].p;
- }
-
- filterValid(moves)
- {
- if (moves.length == 0)
- return [];
- const color = this.turn;
- return moves.filter(m => {
- const L = this.moves.length;
- if (L > 0 && this.oppositeMoves(this.moves[L-1], m))
- return false;
- this.play(m);
- const res = !this.underCheck(color);
- this.undo(m);
- return res;
- });
- }
-
- isAttackedByPawn([x,y], colors)
- {
- for (let c of colors)
- {
- const color = (c=="c" ? this.turn : c);
- let pawnShift = (color=="w" ? 1 : -1);
- if (x+pawnShift>=0 && x+pawnShift<8)
- {
- for (let i of [-1,1])
- {
- if (y+i>=0 && y+i<8 && this.getPiece(x+pawnShift,y+i)==V.PAWN
- && this.getColor(x+pawnShift,y+i)==c)
- {
- return true;
- }
- }
- }
- }
- return false;
- }
-
- underCheck(color)
- {
- return this.isAttacked(this.kingPos[color], [V.GetOppCol(color),'c']);
- }
-
- getCheckSquares(color)
- {
- // Artifically change turn, for checkered pawns
- this.turn = V.GetOppCol(color);
- const kingAttacked = this.isAttacked(
- this.kingPos[color], [V.GetOppCol(color),'c']);
- let res = kingAttacked
- ? [JSON.parse(JSON.stringify(this.kingPos[color]))] //need to duplicate!
- : [];
- this.turn = color;
- return res;
- }
-
- updateVariables(move)
- {
- super.updateVariables(move);
- // Does this move turn off a 2-squares pawn flag?
- const secondRank = [1,6];
- if (secondRank.includes(move.start.x) && move.vanish[0].p == V.PAWN)
- this.pawnFlags[move.start.x==6 ? "w" : "b"][move.start.y] = false;
- }
-
- checkGameEnd()
- {
- const color = this.turn;
- // Artifically change turn, for checkered pawns
- this.turn = V.GetOppCol(this.turn);
- const res = this.isAttacked(this.kingPos[color], [V.GetOppCol(color),'c'])
- ? (color == "w" ? "0-1" : "1-0")
- : "1/2";
- this.turn = V.GetOppCol(this.turn);
- return res;
- }
-
- evalPosition()
- {
- let evaluation = 0;
- //Just count material for now, considering checkered neutral (...)
- 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)
- {
- const sqColor = this.getColor(i,j);
- const sign = sqColor == "w" ? 1 : (sqColor=="b" ? -1 : 0);
- evaluation += sign * V.VALUES[this.getPiece(i,j)];
- }
- }
- }
- return evaluation;
- }
-
- static GenRandInitFen()
- {
- const randFen = ChessRules.GenRandInitFen();
- // Add 16 pawns flags:
- return randFen.replace(" w 1111", " w 11111111111111111111");
- }
-
- getFlagsFen()
- {
- let fen = super.getFlagsFen();
- // Add pawns flags
- for (let c of ['w','b'])
- {
- for (let i=0; i<8; i++)
- fen += this.pawnFlags[c][i] ? '1' : '0';
- }
- return fen;
- }
-
- getNotation(move)
- {
- if (move.appear.length == 2)
- {
- // Castle
- if (move.end.y < move.start.y)
- return "0-0-0";
- else
- return "0-0";
- }
-
- // Translate final square
- const finalSquare = V.CoordsToSquare(move.end);
-
- const piece = this.getPiece(move.start.x, move.start.y);
- if (piece == V.PAWN)
- {
- // Pawn move
- let notation = "";
- if (move.vanish.length > 1)
- {
- // Capture
- const startColumn = V.CoordToColumn(move.start.y);
- notation = startColumn + "x" + finalSquare +
- "=" + move.appear[0].p.toUpperCase();
- }
- else //no capture
- {
- notation = finalSquare;
- if (move.appear.length > 0 && piece != move.appear[0].p) //promotion
- notation += "=" + move.appear[0].p.toUpperCase();
- }
- return notation;
- }
-
- else
- {
- // Piece movement
- return piece.toUpperCase() + (move.vanish.length > 1 ? "x" : "") + finalSquare
- + (move.vanish.length > 1 ? "=" + move.appear[0].p.toUpperCase() : "");
- }
- }
+ static getPpath(b)
+ {
+ return b[0]=='c' ? "Checkered/"+b : b;
+ }
+
+ static board2fen(b)
+ {
+ const checkered_codes = {
+ 'p': 's',
+ 'q': 't',
+ 'r': 'u',
+ 'b': 'c',
+ 'n': 'o',
+ };
+ if (b[0]=="c")
+ return checkered_codes[b[1]];
+ return ChessRules.board2fen(b);
+ }
+
+ static fen2board(f)
+ {
+ // Tolerate upper-case versions of checkered pieces (why not?)
+ const checkered_pieces = {
+ 's': 'p',
+ 'S': 'p',
+ 't': 'q',
+ 'T': 'q',
+ 'u': 'r',
+ 'U': 'r',
+ 'c': 'b',
+ 'C': 'b',
+ 'o': 'n',
+ 'O': 'n',
+ };
+ if (Object.keys(checkered_pieces).includes(f))
+ return 'c'+checkered_pieces[f];
+ return ChessRules.fen2board(f);
+ }
+
+ static get PIECES()
+ {
+ return ChessRules.PIECES.concat(['s','t','u','c','o']);
+ }
+
+ setOtherVariables(fen)
+ {
+ super.setOtherVariables(fen);
+ // Local stack of non-capturing checkered moves:
+ this.cmoves = [];
+ const cmove = fen.split(" ")[5];
+ if (cmove == "-")
+ this.cmoves.push(null);
+ else
+ {
+ this.cmoves.push({
+ start: ChessRules.SquareToCoords(cmove.substr(0,2)),
+ end: ChessRules.SquareToCoords(cmove.substr(2)),
+ });
+ }
+ }
+
+ static IsGoodFen(fen)
+ {
+ if (!ChessRules.IsGoodFen(fen))
+ return false;
+ const fenParts = fen.split(" ");
+ if (fenParts.length != 6)
+ return false;
+ if (fenParts[5] != "-" && !fenParts[5].match(/^([a-h][1-8]){2}$/))
+ return false;
+ return true;
+ }
+
+ static IsGoodFlags(flags)
+ {
+ // 4 for castle + 16 for pawns
+ return !!flags.match(/^[01]{20,20}$/);
+ }
+
+ setFlags(fenflags)
+ {
+ super.setFlags(fenflags); //castleFlags
+ this.pawnFlags =
+ {
+ "w": [...Array(8).fill(true)], //pawns can move 2 squares?
+ "b": [...Array(8).fill(true)],
+ };
+ if (!fenflags)
+ return;
+ const flags = fenflags.substr(4); //skip first 4 digits, for castle
+ for (let c of ['w','b'])
+ {
+ for (let i=0; i<8; i++)
+ this.pawnFlags[c][i] = (flags.charAt((c=='w'?0:8)+i) == '1');
+ }
+ }
+
+ aggregateFlags()
+ {
+ return [this.castleFlags, this.pawnFlags];
+ }
+
+ disaggregateFlags(flags)
+ {
+ this.castleFlags = flags[0];
+ this.pawnFlags = flags[1];
+ }
+
+ getCmove(move)
+ {
+ if (move.appear[0].c == 'c' && move.vanish.length == 1)
+ return {start: move.start, end: move.end};
+ return null;
+ }
+
+ canTake([x1,y1], [x2,y2])
+ {
+ const color1 = this.getColor(x1,y1);
+ const color2 = this.getColor(x2,y2);
+ // Checkered aren't captured
+ return color1 != color2 && color2 != 'c' && (color1 != 'c' || color2 != this.turn);
+ }
+
+ // Post-processing: apply "checkerization" of standard moves
+ getPotentialMovesFrom([x,y])
+ {
+ let standardMoves = super.getPotentialMovesFrom([x,y]);
+ const lastRank = this.turn == "w" ? 0 : 7;
+ if (this.getPiece(x,y) == V.KING)
+ return standardMoves; //king has to be treated differently (for castles)
+ let moves = [];
+ standardMoves.forEach(m => {
+ if (m.vanish[0].p == V.PAWN)
+ {
+ if (Math.abs(m.end.x-m.start.x)==2 && !this.pawnFlags[this.turn][m.start.y])
+ return; //skip forbidden 2-squares jumps
+ if (this.board[m.end.x][m.end.y] == V.EMPTY && m.vanish.length==2
+ && this.getColor(m.start.x,m.start.y) == 'c')
+ {
+ return; //checkered pawns cannot take en-passant
+ }
+ }
+ if (m.vanish.length == 1)
+ moves.push(m); //no capture
+ else
+ {
+ // A capture occured (m.vanish.length == 2)
+ m.appear[0].c = "c";
+ moves.push(m);
+ if (m.appear[0].p != m.vanish[1].p //avoid promotions (already treated):
+ && (m.vanish[0].p != V.PAWN || m.end.x != lastRank))
+ {
+ // Add transformation into captured piece
+ let m2 = JSON.parse(JSON.stringify(m));
+ m2.appear[0].p = m.vanish[1].p;
+ moves.push(m2);
+ }
+ }
+ });
+ return moves;
+ }
+
+ canIplay(side, [x,y])
+ {
+ return (side == this.turn && [side,'c'].includes(this.getColor(x,y)));
+ }
+
+ // Does m2 un-do m1 ? (to disallow undoing checkered moves)
+ oppositeMoves(m1, m2)
+ {
+ return (!!m1 && m2.appear[0].c == 'c'
+ && m2.appear.length == 1 && m2.vanish.length == 1
+ && m1.start.x == m2.end.x && m1.end.x == m2.start.x
+ && m1.start.y == m2.end.y && m1.end.y == m2.start.y);
+ }
+
+ filterValid(moves)
+ {
+ if (moves.length == 0)
+ return [];
+ const color = this.turn;
+ return moves.filter(m => {
+ const L = this.cmoves.length; //at least 1: init from FEN
+ if (this.oppositeMoves(this.cmoves[L-1], m))
+ return false;
+ this.play(m);
+ const res = !this.underCheck(color);
+ this.undo(m);
+ return res;
+ });
+ }
+
+ isAttackedByPawn([x,y], colors)
+ {
+ for (let c of colors)
+ {
+ const color = (c=="c" ? this.turn : c);
+ let pawnShift = (color=="w" ? 1 : -1);
+ if (x+pawnShift>=0 && x+pawnShift<8)
+ {
+ for (let i of [-1,1])
+ {
+ if (y+i>=0 && y+i<8 && this.getPiece(x+pawnShift,y+i)==V.PAWN
+ && this.getColor(x+pawnShift,y+i)==c)
+ {
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ underCheck(color)
+ {
+ return this.isAttacked(this.kingPos[color], [V.GetOppCol(color),'c']);
+ }
+
+ getCheckSquares(color)
+ {
+ // Artifically change turn, for checkered pawns
+ this.turn = V.GetOppCol(color);
+ const kingAttacked = this.isAttacked(
+ this.kingPos[color], [V.GetOppCol(color),'c']);
+ let res = kingAttacked
+ ? [JSON.parse(JSON.stringify(this.kingPos[color]))] //need to duplicate!
+ : [];
+ this.turn = color;
+ return res;
+ }
+
+ updateVariables(move)
+ {
+ super.updateVariables(move);
+ // Does this move turn off a 2-squares pawn flag?
+ const secondRank = [1,6];
+ if (secondRank.includes(move.start.x) && move.vanish[0].p == V.PAWN)
+ this.pawnFlags[move.start.x==6 ? "w" : "b"][move.start.y] = false;
+ }
+
+ getCurrentScore()
+ {
+ if (this.atLeastOneMove()) // game not over
+ return "*";
+
+ const color = this.turn;
+ // Artifically change turn, for checkered pawns
+ this.turn = V.GetOppCol(this.turn);
+ const res = this.isAttacked(this.kingPos[color], [V.GetOppCol(color),'c'])
+ ? (color == "w" ? "0-1" : "1-0")
+ : "1/2";
+ this.turn = V.GetOppCol(this.turn);
+ return res;
+ }
+
+ evalPosition()
+ {
+ let evaluation = 0;
+ //Just count material for now, considering checkered neutral (...)
+ 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)
+ {
+ const sqColor = this.getColor(i,j);
+ const sign = sqColor == "w" ? 1 : (sqColor=="b" ? -1 : 0);
+ evaluation += sign * V.VALUES[this.getPiece(i,j)];
+ }
+ }
+ }
+ return evaluation;
+ }
+
+ static GenRandInitFen()
+ {
+ const randFen = ChessRules.GenRandInitFen();
+ // Add 16 pawns flags + empty cmove:
+ return randFen.replace(" w 0 1111", " w 0 11111111111111111111 -");
+ }
+
+ static ParseFen(fen)
+ {
+ const fenParsed = ChessRules.ParseFen(fen);
+ return Object.assign({},
+ ChessRules.ParseFen(fen),
+ {cmove: fen.split(" ")[5]});
+ }
+
+ getFen()
+ {
+ const L = this.cmoves.length;
+ const cmoveFen = (!this.cmoves[L-1]
+ ? "-"
+ : ChessRules.CoordsToSquare(this.cmoves[L-1].start)
+ + ChessRules.CoordsToSquare(this.cmoves[L-1].end));
+ return super.getFen() + " " + cmoveFen;
+ }
+
+ getFlagsFen()
+ {
+ let fen = super.getFlagsFen();
+ // Add pawns flags
+ for (let c of ['w','b'])
+ {
+ for (let i=0; i<8; i++)
+ fen += this.pawnFlags[c][i] ? '1' : '0';
+ }
+ return fen;
+ }
+
+ // TODO (design): this cmove update here or in (un)updateVariables ?
+ play(move)
+ {
+ this.cmoves.push( this.getCmove(move) );
+ super.play(move);
+ }
+
+ undo(move)
+ {
+ this.cmoves.pop();
+ super.undo(move);
+ }
+
+ getNotation(move)
+ {
+ if (move.appear.length == 2)
+ {
+ // Castle
+ if (move.end.y < move.start.y)
+ return "0-0-0";
+ else
+ return "0-0";
+ }
+
+ // Translate final square
+ const finalSquare = V.CoordsToSquare(move.end);
+
+ const piece = this.getPiece(move.start.x, move.start.y);
+ if (piece == V.PAWN)
+ {
+ // Pawn move
+ let notation = "";
+ if (move.vanish.length > 1)
+ {
+ // Capture
+ const startColumn = V.CoordToColumn(move.start.y);
+ notation = startColumn + "x" + finalSquare +
+ "=" + move.appear[0].p.toUpperCase();
+ }
+ else //no capture
+ {
+ notation = finalSquare;
+ if (move.appear.length > 0 && piece != move.appear[0].p) //promotion
+ notation += "=" + move.appear[0].p.toUpperCase();
+ }
+ return notation;
+ }
+
+ else
+ {
+ // Piece movement
+ return piece.toUpperCase() + (move.vanish.length > 1 ? "x" : "") + finalSquare
+ + (move.vanish.length > 1 ? "=" + move.appear[0].p.toUpperCase() : "");
+ }
+ }
}