return ChessRules.fen2board(f);
}
- static GetFlags(fen)
+ setFlags(fen)
{
- let flags = [
- ChessRules.GetFlags(fen), //castle
- {
- "w": new Array(8), //pawns can move 2 squares
- "b": new Array(8)
- }
- ];
- const fenFlags = fen.split(" ")[1].substr(4); //skip first 4 digits, for castle
+ super.setFlags(fen); //castleFlags
+ this.pawnFlags =
+ {
+ "w": new Array(8), //pawns can move 2 squares?
+ "b": new Array(8)
+ };
+ const flags = fen.split(" ")[1].substr(4); //skip first 4 digits, for castle
for (let c of ['w','b'])
{
for (let i=0; i<8; i++)
- flags[1][c][i] = (fenFlags.charAt((c=='w'?0:8)+i) == '1');
+ this.pawnFlags[c][i] = (flags.charAt((c=='w'?0:8)+i) == '1');
}
- return flags;
}
- 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);
+ // Aggregates flags into one object
+ get flags() {
+ return [this.castleFlags, this.pawnFlags];
}
- addCaptures([sx,sy], [ex,ey], moves)
+ // Reverse operation
+ parseFlags(flags)
{
- const piece = this.getPiece(sx,sy);
- if (piece != VariantRules.KING)
- {
- moves.push(this.getBasicMove([sx,sy], [ex,ey], {c:'c',p:piece}));
- const takePiece = this.getPiece(ex,ey);
- if (takePiece != piece)
- moves.push(this.getBasicMove([sx,sy], [ex,ey], {c:'c',p:takePiece}));
- }
- else
- moves.push(this.getBasicMove([sx,sy], [ex,ey]));
+ this.castleFlags = flags[0];
+ this.pawnFlags = flags[1];
}
- // Generic method to find possible moves of non-pawn pieces ("sliding or jumping")
- getSlideNJumpMoves([x,y], steps, oneStep)
- {
- const color = this.getColor(x,y);
- let moves = [];
- const [sizeX,sizeY] = VariantRules.size;
- outerLoop:
- for (var loop=0; loop<steps.length; loop++)
- {
- let step = steps[loop];
- let i = x + step[0];
- let j = y + step[1];
- while (i>=0 && i<sizeX && j>=0 && j<sizeY && this.board[i][j] == VariantRules.EMPTY)
- {
- moves.push(this.getBasicMove([x,y], [i,j])); //no capture
- if (oneStep !== undefined)
- continue outerLoop;
- i += step[0];
- j += step[1];
- }
- if (i>=0 && i<8 && j>=0 && j<8 && this.canTake([x,y], [i,j]))
- this.addCaptures([x,y], [i,j], moves);
- }
- return moves;
- }
-
- // What are the pawn moves from square x,y considering color "color" ?
- getPotentialPawnMoves([x,y])
+ canTake([x1,y1], [x2,y2])
{
- const color = this.getColor(x,y);
- var moves = [];
- var V = VariantRules;
- let [sizeX,sizeY] = VariantRules.size;
- const c = (color == 'c' ? this.turn : color);
- const shift = (c == "w" ? -1 : 1);
- let startRank = (c == "w" ? sizeY-2 : 1);
- let lastRank = (c == "w" ? 0 : sizeY-1);
-
- if (x+shift >= 0 && x+shift < sizeX && x+shift != lastRank)
- {
- // Normal moves
- if (this.board[x+shift][y] == V.EMPTY)
- {
- moves.push(this.getBasicMove([x,y], [x+shift,y]));
- if (x==startRank && this.board[x+2*shift][y] == V.EMPTY && this.flags[1][c][y])
- {
- // Two squares jump
- moves.push(this.getBasicMove([x,y], [x+2*shift,y]));
- }
- }
- // Captures
- if (y>0 && this.canTake([x,y], [x+shift,y-1]) && this.board[x+shift][y-1] != V.EMPTY)
- this.addCaptures([x,y], [x+shift,y-1], moves);
- if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1]) && this.board[x+shift][y+1] != V.EMPTY)
- this.addCaptures([x,y], [x+shift,y+1], moves);
- }
-
- if (x+shift == lastRank)
- {
- // Promotion
- let promotionPieces = [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN];
- promotionPieces.forEach(p => {
- // Normal move
- if (this.board[x+shift][y] == V.EMPTY)
- moves.push(this.getBasicMove([x,y], [x+shift,y], {c:color,p:p}));
- // Captures
- if (y>0 && this.canTake([x,y], [x+shift,y-1]) && this.board[x+shift][y-1] != V.EMPTY)
- moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:'c',p:p}));
- if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1]) && this.board[x+shift][y+1] != V.EMPTY)
- moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:'c',p:p}));
- });
- }
-
- // En passant
- const Lep = this.epSquares.length;
- const epSquare = Lep>0 ? this.epSquares[Lep-1] : undefined;
- if (!!epSquare && epSquare.x == x+shift && Math.abs(epSquare.y - y) == 1)
- {
- let epStep = epSquare.y - y;
- var enpassantMove = this.getBasicMove([x,y], [x+shift,y+epStep]);
- enpassantMove.vanish.push({
- x: x,
- y: y+epStep,
- p: 'p',
- c: this.getColor(x,y+epStep)
- });
- enpassantMove.appear[0].c = 'c';
- moves.push(enpassantMove);
- }
-
- return moves;
+ 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);
}
- getCastleMoves([x,y])
+ // Post-processing: apply "checkerization" of standard moves
+ getPotentialMovesFrom([x,y])
{
- const c = this.getColor(x,y);
- if (x != (c=="w" ? 7 : 0) || y != this.INIT_COL_KING[c])
- return []; //x isn't first rank, or king has moved (shortcut)
-
- const V = VariantRules;
-
- // Castling ?
- const oppCol = this.getOppCol(c);
+ let standardMoves = super.getPotentialMovesFrom([x,y]);
+ if (this.getPiece(x,y) == VariantRules.KING)
+ return standardMoves; //king has to be treated differently (for castles)
let moves = [];
- let i = 0;
- const finalSquares = [ [2,3], [6,5] ]; //king, then rook
- castlingCheck:
- for (let castleSide=0; castleSide < 2; castleSide++) //large, then small
- {
- if (!this.flags[0][c][castleSide])
- continue;
- // If this code is reached, rooks and king are on initial position
-
- // Nothing on the path of the king (and no checks; OK also if y==finalSquare)?
- let step = finalSquares[castleSide][0] < y ? -1 : 1;
- for (i=y; i!=finalSquares[castleSide][0]; i+=step)
+ standardMoves.forEach(m => {
+ if (m.vanish[0].p == VariantRules.PAWN && Math.abs(m.end.x-m.start.x)==2
+ && !this.pawnFlags[this.turn][m.start.y])
{
- if (this.isAttacked([x,i], oppCol) || (this.board[x][i] != V.EMPTY &&
- // NOTE: next check is enough, because of chessboard constraints
- (this.getColor(x,i) != c || ![V.KING,V.ROOK].includes(this.getPiece(x,i)))))
- {
- continue castlingCheck;
- }
+ return; //skip forbidden 2-squares jumps
}
-
- // Nothing on the path to the rook?
- step = castleSide == 0 ? -1 : 1;
- for (i = y + step; i != this.INIT_COL_ROOK[c][castleSide]; i += step)
- {
- if (this.board[x][i] != V.EMPTY)
- continue castlingCheck;
- }
- const rookPos = this.INIT_COL_ROOK[c][castleSide];
-
- // Nothing on final squares, except maybe king and castling rook?
- for (i=0; i<2; i++)
+ if (m.vanish.length == 1)
+ moves.push(m); //no capture
+ else
{
- if (this.board[x][finalSquares[castleSide][i]] != V.EMPTY &&
- this.getPiece(x,finalSquares[castleSide][i]) != V.KING &&
- finalSquares[castleSide][i] != rookPos)
+ // A capture occured (m.vanish.length == 2)
+ m.appear[0].c = "c";
+ moves.push(JSON.parse(JSON.stringify(m)));
+ if (m.appear[0].p != m.vanish[1].p)
{
- continue castlingCheck;
+ // Add transformation into captured piece
+ let m2 = JSON.parse(JSON.stringify(m));
+ m2.vanish[1].p = m.appear[0].p;
+ moves.push(m2);
}
}
-
- // If this code is reached, castle is valid
- moves.push( new Move({
- appear: [
- new PiPo({x:x,y:finalSquares[castleSide][0],p:V.KING,c:c}),
- new PiPo({x:x,y:finalSquares[castleSide][1],p:V.ROOK,c:c})],
- vanish: [
- new PiPo({x:x,y:y,p:V.KING,c:c}),
- new PiPo({x:x,y:rookPos,p:V.ROOK,c:c})],
- end: Math.abs(y - rookPos) <= 2
- ? {x:x, y:rookPos}
- : {x:x, y:y + 2 * (castleSide==0 ? -1 : 1)}
- }) );
- }
-
+ });
return moves;
}
updateVariables(move)
{
- const piece = this.getPiece(move.start.x,move.start.y);
const c = this.getColor(move.start.x,move.start.y);
-
if (c != 'c') //checkered not concerned by castle flags
- {
- const firstRank = (c == "w" ? 7 : 0);
- // Update king position + flags
- if (piece == VariantRules.KING && move.appear.length > 0)
- {
- this.kingPos[c][0] = move.appear[0].x;
- this.kingPos[c][1] = move.appear[0].y;
- this.flags[0][c] = [false,false];
- return;
- }
- const oppCol = this.getOppCol(c);
- const oppFirstRank = 7 - firstRank;
- if (move.start.x == firstRank //our rook moves?
- && this.INIT_COL_ROOK[c].includes(move.start.y))
- {
- const flagIdx = move.start.y == this.INIT_COL_ROOK[c][0] ? 0 : 1;
- this.flags[0][c][flagIdx] = false;
- }
- else if (move.end.x == oppFirstRank //we took opponent rook?
- && this.INIT_COL_ROOK[c].includes(move.end.y))
- {
- const flagIdx = move.end.y == this.INIT_COL_ROOK[oppCol][0] ? 0 : 1;
- this.flags[0][oppCol][flagIdx] = false;
- }
- }
+ super.updateVariables(move);
// Does it turn off a 2-squares pawn flag?
const secondRank = [1,6];
if (secondRank.includes(move.start.x) && move.vanish[0].p == VariantRules.PAWN)
- this.flags[1][move.start.x==6 ? "w" : "b"][move.start.y] = false;
+ this.pawnFlags[move.start.x==6 ? "w" : "b"][move.start.y] = false;
}
checkGameEnd()
getFlagsFen()
{
- let fen = "";
- // Add castling flags
- for (let c of ['w','b'])
- {
- for (let i=0; i<2; i++)
- fen += this.flags[0][c][i] ? '1' : '0';
- }
+ let fen = super.getFlagsFen();
// Add pawns flags
for (let c of ['w','b'])
{
for (let i=0; i<8; i++)
- fen += this.flags[1][c][i] ? '1' : '0';
+ fen += this.pawnFlags[c][i] ? '1' : '0';
}
return fen;
}
projects / vchess.git / blobdiff