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 IsGoodEnpassant(enpassant)
  22     {
  23         if (enpassant != "-")
  24         {
  25             const squares = enpassant.split(",");
  26             if (squares.length > 2)
  27                 return false;
  28             for (let sq of squares)
  29             {
  30                 const ep = V.SquareToCoords(sq);
  31                 if (isNaN(ep.x) || !V.OnBoard(ep))
  32                     return false;
  33             }
  34         }
  35         return true;
  36     }
  37
  38     static ParseFen(fen)
  39     {
  40         const fenParts = fen.split(" ");
  41         return Object.assign(
  42             ChessRules.ParseFen(fen),
  43             { captured: fenParts[4] }
  44         );
  45     }
  46
  47     getFen()
  48     {
  49         return super.getFen() + " " + this.getCapturedFen();
  50     }
  51
  52     getCapturedFen()
  53     {
  54         let counts = _.map(_.range(10), 0);
  55         for (let i=0; i<V.PIECES.length-1; i++) //-1: no king captured
  56         {
  57             counts[i] = this.captured["w"][V.PIECES[i]];
  58             counts[5+i] = this.captured["b"][V.PIECES[i]];
  59         }
  60         return counts.join("");
  61     }
  62
  63     setOtherVariables(fen)
  64     {
  65         super.setOtherVariables(fen);
  66         const fenParsed = V.ParseFen(fen);
  67         // Initialize captured pieces' counts from FEN
  68         this.captured =
  69         {
  70             "w":
  71             {
  72                 [V.PAWN]: parseInt(fenParsed.captured[0]),
  73                 [V.ROOK]: parseInt(fenParsed.captured[1]),
  74                 [V.KNIGHT]: parseInt(fenParsed.captured[2]),
  75                 [V.BISHOP]: parseInt(fenParsed.captured[3]),
  76                 [V.QUEEN]: parseInt(fenParsed.captured[4]),
  77             },
  78             "b":
  79             {
  80                 [V.PAWN]: parseInt(fenParsed.captured[5]),
  81                 [V.ROOK]: parseInt(fenParsed.captured[6]),
  82                 [V.KNIGHT]: parseInt(fenParsed.captured[7]),
  83                 [V.BISHOP]: parseInt(fenParsed.captured[8]),
  84                 [V.QUEEN]: parseInt(fenParsed.captured[9]),
  85             }
  86         };
  87     }
  88
  89     static get size() { return {x:10,y:10}; }
  90
  91     static get MARSHALL() { return 'm'; } //rook+knight
  92     static get CARDINAL() { return 'c'; } //bishop+knight
  93
  94     static get PIECES()
  95     {
  96         return ChessRules.PIECES.concat([V.MARSHALL,V.CARDINAL]);
  97     }
  98
  99     // There may be 2 enPassant squares (if pawn jump 3 squares)
 100     getEnpassantFen()
 101     {
 102         const L = this.epSquares.length;
 103         if (!this.epSquares[L-1])
 104             return "-"; //no en-passant
 105         let res = "";
 106         this.epSquares[L-1].forEach(sq => {
 107             res += V.CoordsToSquare(sq) + ",";
 108         });
 109         return res.slice(0,-1); //remove last comma
 110     }
 111
 112     // En-passant after 2-sq or 3-sq jumps
 113     getEpSquare(moveOrSquare)
 114     {
 115         if (!moveOrSquare)
 116             return undefined;
 117         if (typeof moveOrSquare === "string")
 118         {
 119             const square = moveOrSquare;
 120             if (square == "-")
 121                 return undefined;
 122             let res = [];
 123             square.split(",").forEach(sq => {
 124                 res.push(V.SquareToCoords(sq));
 125             });
 126             return res;
 127         }
 128         // Argument is a move:
 129         const move = moveOrSquare;
 130         const [sx,sy,ex] = [move.start.x,move.start.y,move.end.x];
 131         if (this.getPiece(sx,sy) == V.PAWN && Math.abs(sx - ex) >= 2)
 132         {
 133             const step = (ex-sx) / Math.abs(ex-sx);
 134             let res = [{
 135                 x: sx + step,
 136                 y: sy
 137             }];
 138             if (sx + 2*step != ex) //3-squares move
 139             {
 140                 res.push({
 141                     x: sx + 2*step,
 142                     y: sy
 143                 });
 144             }
 145             return res;
 146         }
 147         return undefined; //default
 148     }
 149
 150     getPotentialMovesFrom([x,y])
 151     {
 152         switch (this.getPiece(x,y))
 153         {
 154             case V.MARSHALL:
 155                 return this.getPotentialMarshallMoves([x,y]);
 156             case V.CARDINAL:
 157                 return this.getPotentialCardinalMoves([x,y]);
 158             default:
 159                 return super.getPotentialMovesFrom([x,y])
 160         }
 161     }
 162
 163     // Special pawn rules: promotions to captured friendly pieces,
 164     // optional on ranks 8-9 and mandatory on rank 10.
 165     getPotentialPawnMoves([x,y])
 166     {
 167         const color = this.turn;
 168         let moves = [];
 169         const [sizeX,sizeY] = [V.size.x,V.size.y];
 170         const shift = (color == "w" ? -1 : 1);
 171         const startRanks = (color == "w" ? [sizeX-2,sizeX-3] : [1,2]);
 172         const lastRanks = (color == "w" ? [0,1,2] : [sizeX-1,sizeX-2,sizeX-3]);
 173
 174         if (x+shift >= 0 && x+shift < sizeX && x+shift != lastRanks[0])
 175         {
 176             // Normal moves
 177             if (this.board[x+shift][y] == V.EMPTY)
 178             {
 179                 moves.push(this.getBasicMove([x,y], [x+shift,y]));
 180                 if (startRanks.includes(x) && this.board[x+2*shift][y] == V.EMPTY)
 181                 {
 182                     // Two squares jump
 183                     moves.push(this.getBasicMove([x,y], [x+2*shift,y]));
 184                     if (x == startRanks[0] && this.board[x+3*shift][y] == V.EMPTY)
 185                     {
 186                         // 3-squares jump
 187                         moves.push(this.getBasicMove([x,y], [x+3*shift,y]));
 188                     }
 189                 }
 190             }
 191             // Captures
 192             if (y>0 && this.canTake([x,y], [x+shift,y-1])
 193                 && this.board[x+shift][y-1] != V.EMPTY)
 194             {
 195                 moves.push(this.getBasicMove([x,y], [x+shift,y-1]));
 196             }
 197             if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
 198                 && this.board[x+shift][y+1] != V.EMPTY)
 199             {
 200                 moves.push(this.getBasicMove([x,y], [x+shift,y+1]));
 201             }
 202         }
 203
 204         if (lastRanks.includes(x+shift))
 205         {
 206             // Promotion
 207             let promotionPieces = [V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN,V.MARSHALL,V.CARDINAL];
 208             promotionPieces.forEach(p => {
 209                 if (this.captured[color][p]==0)
 210                     return;
 211                 // Normal move
 212                 if (this.board[x+shift][y] == V.EMPTY)
 213                     moves.push(this.getBasicMove([x,y], [x+shift,y], {c:color,p:p}));
 214                 // Captures
 215                 if (y>0 && this.canTake([x,y], [x+shift,y-1])
 216                     && this.board[x+shift][y-1] != V.EMPTY)
 217                 {
 218                     moves.push(this.getBasicMove([x,y], [x+shift,y-1], {c:color,p:p}));
 219                 }
 220                 if (y<sizeY-1 && this.canTake([x,y], [x+shift,y+1])
 221                     && this.board[x+shift][y+1] != V.EMPTY)
 222                 {
 223                     moves.push(this.getBasicMove([x,y], [x+shift,y+1], {c:color,p:p}));
 224                 }
 225             });
 226         }
 227
 228         // En passant
 229         const Lep = this.epSquares.length;
 230         const epSquare = Lep>0 ? this.epSquares[Lep-1] : undefined;
 231         if (!!epSquare)
 232         {
 233             for (let epsq of epSquare)
 234             {
 235                 // TODO: some redundant checks
 236                 if (epsq.x == x+shift && Math.abs(epsq.y - y) == 1)
 237                 {
 238                     var enpassantMove = this.getBasicMove([x,y], [x+shift,epsq.y]);
 239                     enpassantMove.vanish.push({
 240                         x: x,
 241                         y: epsq.y,
 242                         p: 'p',
 243                         c: this.getColor(x,epsq.y)
 244                     });
 245                     moves.push(enpassantMove);
 246                 }
 247             }
 248         }
 249
 250         return moves;
 251     }
 252
 253     // TODO: different castle?
 254
 255     getPotentialMarshallMoves(sq)
 256     {
 257         return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]).concat(
 258             this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
 259     }
 260
 261     getPotentialCardinalMoves(sq)
 262     {
 263         return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]).concat(
 264             this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
 265     }
 266
 267     isAttacked(sq, colors)
 268     {
 269         return super.isAttacked(sq, colors)
 270             || this.isAttackedByMarshall(sq, colors)
 271             || this.isAttackedByCardinal(sq, colors);
 272     }
 273
 274     isAttackedByMarshall(sq, colors)
 275     {
 276         return this.isAttackedBySlideNJump(sq, colors, V.MARSHALL, V.steps[V.ROOK])
 277             || this.isAttackedBySlideNJump(
 278                 sq, colors, V.MARSHALL, V.steps[V.KNIGHT], "oneStep");
 279     }
 280
 281     isAttackedByCardinal(sq, colors)
 282     {
 283         return this.isAttackedBySlideNJump(sq, colors, V.CARDINAL, V.steps[V.BISHOP])
 284             || this.isAttackedBySlideNJump(
 285                 sq, colors, V.CARDINAL, V.steps[V.KNIGHT], "oneStep");
 286     }
 287
 288     updateVariables(move)
 289     {
 290         super.updateVariables(move);
 291         if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
 292         {
 293             // Capture: update this.captured
 294             this.captured[move.vanish[1].c][move.vanish[1].p]++;
 295         }
 296     }
 297
 298     unupdateVariables(move)
 299     {
 300         super.unupdateVariables(move);
 301         if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
 302             this.captured[move.vanish[1].c][move.vanish[1].p]--;
 303     }
 304
 305     static get VALUES()
 306     {
 307         return Object.assign(
 308             ChessRules.VALUES,
 309             {'c': 5, 'm': 7} //experimental
 310         );
 311     }
 312
 313     static get SEARCH_DEPTH() { return 2; }
 314
 315     // TODO: this function could be generalized and shared better (how ?!...)
 316     static GenRandInitFen()
 317     {
 318         let pieces = { "w": new Array(10), "b": new Array(10) };
 319         // Shuffle pieces on first and last rank
 320         for (let c of ["w","b"])
 321         {
 322             let positions = _.range(10);
 323
 324             // Get random squares for bishops
 325             let randIndex = 2 * _.random(4);
 326             let bishop1Pos = positions[randIndex];
 327             // The second bishop must be on a square of different color
 328             let randIndex_tmp = 2 * _.random(4) + 1;
 329             let bishop2Pos = positions[randIndex_tmp];
 330             // Remove chosen squares
 331             positions.splice(Math.max(randIndex,randIndex_tmp), 1);
 332             positions.splice(Math.min(randIndex,randIndex_tmp), 1);
 333
 334             // Get random squares for knights
 335             randIndex = _.random(7);
 336             let knight1Pos = positions[randIndex];
 337             positions.splice(randIndex, 1);
 338             randIndex = _.random(6);
 339             let knight2Pos = positions[randIndex];
 340             positions.splice(randIndex, 1);
 341
 342             // Get random square for queen
 343             randIndex = _.random(5);
 344             let queenPos = positions[randIndex];
 345             positions.splice(randIndex, 1);
 346
 347             // ...random square for marshall
 348             randIndex = _.random(4);
 349             let marshallPos = positions[randIndex];
 350             positions.splice(randIndex, 1);
 351
 352             // ...random square for cardinal
 353             randIndex = _.random(3);
 354             let cardinalPos = positions[randIndex];
 355             positions.splice(randIndex, 1);
 356
 357             // Rooks and king positions are now fixed, because of the ordering rook-king-rook
 358             let rook1Pos = positions[0];
 359             let kingPos = positions[1];
 360             let rook2Pos = positions[2];
 361
 362             // Finally put the shuffled pieces in the board array
 363             pieces[c][rook1Pos] = 'r';
 364             pieces[c][knight1Pos] = 'n';
 365             pieces[c][bishop1Pos] = 'b';
 366             pieces[c][queenPos] = 'q';
 367             pieces[c][marshallPos] = 'm';
 368             pieces[c][cardinalPos] = 'c';
 369             pieces[c][kingPos] = 'k';
 370             pieces[c][bishop2Pos] = 'b';
 371             pieces[c][knight2Pos] = 'n';
 372             pieces[c][rook2Pos] = 'r';
 373         }
 374         return pieces["b"].join("") +
 375             "/pppppppppp/10/10/10/10/10/10/PPPPPPPPPP/" +
 376             pieces["w"].join("").toUpperCase() +
 377             " w 1111 - 0000000000";
 378     }
 379 }
 380
 381 const VariantRules = GrandRules;