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