public/javascripts/variants/Grand.js

   1 // NOTE: initial setup differs from the original; see
   2 // https://www.chessvariants.com/large.dir/freeling.html
   3 class GrandRules extends ChessRules
   4 {
   5     static getPpath(b)
   6     {
   7         return ([V.MARSHALL,V.CARDINAL].includes(b[1]) ? "Grand/" : "") + b;
   8     }
   9
  10     static IsGoodFen(fen)
  11     {
  12         if (!ChessRules.IsGoodFen(fen))
  13             return false;
  14         const fenParsed = V.ParseFen(fen);
  15         // 5) Check captures
  16         if (!fenParsed.captured || !fenParsed.captured.match(/^[0-9]{10,10}$/))
  17             return false;
  18         return true;
  19     }
  20
  21     static GenRandInitFen()
  22     {
  23         const fen = ChessRules.GenRandInitFen();
  24         return fen.replace(" w 1111", " w 1111 0000000000");
  25     }
  26
  27     getFen()
  28     {
  29         return super.getFen() + " " + this.getCapturedFen();
  30     }
  31
  32     getCapturedFen()
  33     {
  34         let counts = _.map(_.range(10), 0);
  35         for (let i=0; i<V.PIECES.length; i++)
  36         {
  37             counts[i] = this.captured["w"][V.PIECES[i]];
  38             counts[5+i] = this.captured["b"][V.PIECES[i]];
  39         }
  40         return counts.join("");
  41     }
  42
  43     setOtherVariables(fen)
  44     {
  45         super.setOtherVariables(fen);
  46         const fenParsed = V.ParseFen(fen);
  47         // Initialize captured pieces' counts from FEN
  48         this.captured =
  49         {
  50             "w":
  51             {
  52                 [V.PAWN]: parseInt(fenParsed.captured[0]),
  53                 [V.ROOK]: parseInt(fenParsed.captured[1]),
  54                 [V.KNIGHT]: parseInt(fenParsed.captured[2]),
  55                 [V.BISHOP]: parseInt(fenParsed.captured[3]),
  56                 [V.QUEEN]: parseInt(fenParsed.captured[4]),
  57             },
  58             "b":
  59             {
  60                 [V.PAWN]: parseInt(fenParsed.captured[5]),
  61                 [V.ROOK]: parseInt(fenParsed.captured[6]),
  62                 [V.KNIGHT]: parseInt(fenParsed.captured[7]),
  63                 [V.BISHOP]: parseInt(fenParsed.captured[8]),
  64                 [V.QUEEN]: parseInt(fenParsed.captured[9]),
  65             }
  66         };
  67     }
  68
  69     static get size() { return {x:10,y:10}; }
  70
  71     static get MARSHALL() { return 'm'; } //rook+knight
  72     static get CARDINAL() { return 'c'; } //bishop+knight
  73
  74     static get PIECES()
  75     {
  76         return ChessRules.PIECES.concat([V.MARSHALL,V.CARDINAL]);
  77     }
  78
  79     // There may be 2 enPassant squares (if pawn jump 3 squares)
  80     getEnpassantFen()
  81     {
  82         const L = this.epSquares.length;
  83         if (!this.epSquares[L-1])
  84             return "-"; //no en-passant
  85         let res = "";
  86         this.epSquares[L-1].forEach(sq => {
  87             res += V.CoordsToSquare(sq) + ",";
  88         });
  89         return res.slice(0,-1); //remove last comma
  90     }
  91
  92     // En-passant after 2-sq or 3-sq jumps
  93     getEpSquare(moveOrSquare)
  94     {
  95         if (!moveOrSquare)
  96             return undefined;
  97         if (typeof moveOrSquare === "string")
  98         {
  99             const square = moveOrSquare;
 100             if (square == "-")
 101                 return undefined;
 102             let res = [];
 103             square.split(",").forEach(sq => {
 104                 res.push(V.SquareToCoords(sq));
 105             });
 106             return res;
 107         }
 108         // Argument is a move:
 109         const move = moveOrSquare;
 110         const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x];
 111         if (this.getPiece(sx,sy) == V.PAWN && Math.abs(sx - ex) >= 2)
 112         {
 113             const step = (ex-sx) / Math.abs(ex-sx);
 114             let res = [{
 115                 x: sx + step,
 116                 y: sy
 117             }];
 118             if (sx + 2*step != ex) //3-squares move
 119             {
 120                 res.push({
 121                     x: sx + 2*step,
 122                     y: sy
 123                 });
 124             }
 125             return res;
 126         }
 127         return undefined; //default
 128     }
 129
 130     getPotentialMovesFrom([x,y])
 131     {
 132         switch (this.getPiece(x,y))
 133         {
 134             case V.MARSHALL:
 135                 return this.getPotentialMarshallMoves([x,y]);
 136             case V.CARDINAL:
 137                 return this.getPotentialCardinalMoves([x,y]);
 138             default:
 139                 return super.getPotentialMovesFrom([x,y])
 140         }
 141     }
 142
 143     // Special pawn rules: promotions to captured friendly pieces,
 144     // optional on ranks 8-9 and mandatory on rank 10.
 145     getPotentialPawnMoves([x,y])
 146     {
 147         const color = this.turn;
 148         let moves = [];
 149         const [sizeX,sizeY] = [V.size.x,V.size.y];
 150         const shift = (color == "w" ? -1 : 1);
 151         const startRanks = (color == "w" ? [sizeX-2,sizeX-3] : [1,2]);
 152         const lastRanks = (color == "w" ? [0,1,2] : [sizeX-1,sizeX-2,sizeX-3]);
 153
 154         if (x+shift >= 0 && x+shift < sizeX && x+shift != lastRanks[0])
 155         {
 156             // Normal moves
 157             if (this.board[x+shift][y] == V.EMPTY)
 158             {
 159                 moves.push(this.getBasicMove([x,y], [x+shift,y]));
 160                 if (startRanks.includes(x) && this.board[x+2*shift][y] == V.EMPTY)
 161                 {
 162                     // Two squares jump
 163                     moves.push(this.getBasicMove([x,y], [x+2*shift,y]));
 164                     if (x == startRanks[0] && this.board[x+3*shift][y] == V.EMPTY)
 165                     {
 166                         // 3-squares jump
 167                         moves.push(this.getBasicMove([x,y], [x+3*shift,y]));
 168                     }
 169                 }
 170             }
 171             // Captures
 172             if (y>0 && this.canTake([x,y], [x+shift,y-1])
 173                 && this.board[x+shift][y-1] != V.EMPTY)
 174             {
 175                 moves.push(this.getBasicMove([x,y], [x+shift,y-1]));
 176             }
 177             if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
 178                 && this.board[x+shift][y+1] != V.EMPTY)
 179             {
 180                 moves.push(this.getBasicMove([x,y], [x+shift,y+1]));
 181             }
 182         }
 183
 184         if (lastRanks.includes(x+shift))
 185         {
 186             // Promotion
 187             let promotionPieces = [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN,V.MARSHALL,V.CARDINAL];
 188             promotionPieces.forEach(p => {
 189                 if (this.captured[color][p]==0)
 190                     return;
 191                 // Normal move
 192                 if (this.board[x+shift][y] == V.EMPTY)
 193                     moves.push(this.getBasicMove([x,y], [x+shift,y], {c:color,p:p}));
 194                 // Captures
 195                 if (y>0 && this.canTake([x,y], [x+shift,y-1])
 196                     && this.board[x+shift][y-1] != V.EMPTY)
 197                 {
 198                     moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:color,p:p}));
 199                 }
 200                 if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
 201                     && this.board[x+shift][y+1] != V.EMPTY)
 202                 {
 203                     moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:color,p:p}));
 204                 }
 205             });
 206         }
 207
 208         // En passant
 209         const Lep = this.epSquares.length;
 210         const epSquare = Lep>0 ? this.epSquares[Lep-1] : undefined;
 211         if (!!epSquare)
 212         {
 213             for (let epsq of epSquare)
 214             {
 215                 // TODO: some redundant checks
 216                 if (epsq.x == x+shift && Math.abs(epsq.y - y) == 1)
 217                 {
 218                     let epStep = epsq.y - y;
 219                     var enpassantMove = this.getBasicMove([x,y], [x+shift,y+epStep]);
 220                     enpassantMove.vanish.push({
 221                         x: x,
 222                         y: y+epStep,
 223                         p: 'p',
 224                         c: this.getColor(x,y+epStep)
 225                     });
 226                     moves.push(enpassantMove);
 227                 }
 228             }
 229         }
 230
 231         return moves;
 232     }
 233
 234     // TODO: different castle?
 235
 236     getPotentialMarshallMoves(sq)
 237     {
 238         return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]).concat(
 239             this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
 240     }
 241
 242     getPotentialCardinalMoves(sq)
 243     {
 244         return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]).concat(
 245             this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
 246     }
 247
 248     isAttacked(sq, colors)
 249     {
 250         return super.isAttacked(sq, colors)
 251             || this.isAttackedByMarshall(sq, colors)
 252             || this.isAttackedByCardinal(sq, colors);
 253     }
 254
 255     isAttackedByMarshall(sq, colors)
 256     {
 257         return this.isAttackedBySlideNJump(sq, colors, V.MARSHALL, V.steps[V.ROOK])
 258             || this.isAttackedBySlideNJump(
 259                 sq, colors, V.MARSHALL, V.steps[V.KNIGHT], "oneStep");
 260     }
 261
 262     isAttackedByCardinal(sq, colors)
 263     {
 264         return this.isAttackedBySlideNJump(sq, colors, V.CARDINAL, V.steps[V.BISHOP])
 265             || this.isAttackedBySlideNJump(
 266                 sq, colors, V.CARDINAL, V.steps[V.KNIGHT], "oneStep");
 267     }
 268
 269     updateVariables(move)
 270     {
 271         super.updateVariables(move);
 272         if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
 273         {
 274             // Capture: update this.captured
 275             this.captured[move.vanish[1].c][move.vanish[1].p]++;
 276         }
 277     }
 278
 279     unupdateVariables(move)
 280     {
 281         super.unupdateVariables(move);
 282         if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
 283             this.captured[move.vanish[1].c][move.vanish[1].p]--;
 284     }
 285
 286     static get VALUES()
 287     {
 288         return Object.assign(
 289             ChessRules.VALUES,
 290             {'c': 5, 'm': 7} //experimental
 291         );
 292     }
 293
 294     static get SEARCH_DEPTH() { return 2; }
 295
 296     // TODO: this function could be generalized and shared better (how ?!...)
 297     static GenRandInitFen()
 298     {
 299         let pieces = { "w": new Array(10), "b": new Array(10) };
 300         // Shuffle pieces on first and last rank
 301         for (let c of ["w","b"])
 302         {
 303             let positions = _.range(10);
 304
 305             // Get random squares for bishops
 306             let randIndex = 2 * _.random(4);
 307             let bishop1Pos = positions[randIndex];
 308             // The second bishop must be on a square of different color
 309             let randIndex_tmp = 2 * _.random(4) + 1;
 310             let bishop2Pos = positions[randIndex_tmp];
 311             // Remove chosen squares
 312             positions.splice(Math.max(randIndex,randIndex_tmp), 1);
 313             positions.splice(Math.min(randIndex,randIndex_tmp), 1);
 314
 315             // Get random squares for knights
 316             randIndex = _.random(7);
 317             let knight1Pos = positions[randIndex];
 318             positions.splice(randIndex, 1);
 319             randIndex = _.random(6);
 320             let knight2Pos = positions[randIndex];
 321             positions.splice(randIndex, 1);
 322
 323             // Get random square for queen
 324             randIndex = _.random(5);
 325             let queenPos = positions[randIndex];
 326             positions.splice(randIndex, 1);
 327
 328             // ...random square for marshall
 329             randIndex = _.random(4);
 330             let marshallPos = positions[randIndex];
 331             positions.splice(randIndex, 1);
 332
 333             // ...random square for cardinal
 334             randIndex = _.random(3);
 335             let cardinalPos = positions[randIndex];
 336             positions.splice(randIndex, 1);
 337
 338             // Rooks and king positions are now fixed, because of the ordering rook-king-rook
 339             let rook1Pos = positions[0];
 340             let kingPos = positions[1];
 341             let rook2Pos = positions[2];
 342
 343             // Finally put the shuffled pieces in the board array
 344             pieces[c][rook1Pos] = 'r';
 345             pieces[c][knight1Pos] = 'n';
 346             pieces[c][bishop1Pos] = 'b';
 347             pieces[c][queenPos] = 'q';
 348             pieces[c][marshallPos] = 'm';
 349             pieces[c][cardinalPos] = 'c';
 350             pieces[c][kingPos] = 'k';
 351             pieces[c][bishop2Pos] = 'b';
 352             pieces[c][knight2Pos] = 'n';
 353             pieces[c][rook2Pos] = 'r';
 354         }
 355         return pieces["b"].join("") +
 356             "/pppppppppp/10/10/10/10/10/10/PPPPPPPPPP/" +
 357             pieces["w"].join("").toUpperCase() +
 358             " w 1111 -";
 359     }
 360 }