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                     var enpassantMove = this.getBasicMove([x,y], [x+shift,epsq.y]);
 222                     enpassantMove.vanish.push({
 223                         x: x,
 224                         y: epsq.y,
 225                         p: 'p',
 226                         c: this.getColor(x,epsq.y)
 227                     });
 228                     moves.push(enpassantMove);
 229                 }
 230             }
 231         }
 232
 233         return moves;
 234     }
 235
 236     // TODO: different castle?
 237
 238     getPotentialMarshallMoves(sq)
 239     {
 240         return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]).concat(
 241             this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
 242     }
 243
 244     getPotentialCardinalMoves(sq)
 245     {
 246         return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]).concat(
 247             this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], "oneStep"));
 248     }
 249
 250     isAttacked(sq, colors)
 251     {
 252         return super.isAttacked(sq, colors)
 253             || this.isAttackedByMarshall(sq, colors)
 254             || this.isAttackedByCardinal(sq, colors);
 255     }
 256
 257     isAttackedByMarshall(sq, colors)
 258     {
 259         return this.isAttackedBySlideNJump(sq, colors, V.MARSHALL, V.steps[V.ROOK])
 260             || this.isAttackedBySlideNJump(
 261                 sq, colors, V.MARSHALL, V.steps[V.KNIGHT], "oneStep");
 262     }
 263
 264     isAttackedByCardinal(sq, colors)
 265     {
 266         return this.isAttackedBySlideNJump(sq, colors, V.CARDINAL, V.steps[V.BISHOP])
 267             || this.isAttackedBySlideNJump(
 268                 sq, colors, V.CARDINAL, V.steps[V.KNIGHT], "oneStep");
 269     }
 270
 271     updateVariables(move)
 272     {
 273         super.updateVariables(move);
 274         if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
 275         {
 276             // Capture: update this.captured
 277             this.captured[move.vanish[1].c][move.vanish[1].p]++;
 278         }
 279     }
 280
 281     unupdateVariables(move)
 282     {
 283         super.unupdateVariables(move);
 284         if (move.vanish.length==2 && move.appear.length==1 && move.vanish[1].p != V.PAWN)
 285             this.captured[move.vanish[1].c][move.vanish[1].p]--;
 286     }
 287
 288     static get VALUES()
 289     {
 290         return Object.assign(
 291             ChessRules.VALUES,
 292             {'c': 5, 'm': 7} //experimental
 293         );
 294     }
 295
 296     static get SEARCH_DEPTH() { return 2; }
 297
 298     // TODO: this function could be generalized and shared better (how ?!...)
 299     static GenRandInitFen()
 300     {
 301         let pieces = { "w": new Array(10), "b": new Array(10) };
 302         // Shuffle pieces on first and last rank
 303         for (let c of ["w","b"])
 304         {
 305             let positions = _.range(10);
 306
 307             // Get random squares for bishops
 308             let randIndex = 2 * _.random(4);
 309             let bishop1Pos = positions[randIndex];
 310             // The second bishop must be on a square of different color
 311             let randIndex_tmp = 2 * _.random(4) + 1;
 312             let bishop2Pos = positions[randIndex_tmp];
 313             // Remove chosen squares
 314             positions.splice(Math.max(randIndex,randIndex_tmp), 1);
 315             positions.splice(Math.min(randIndex,randIndex_tmp), 1);
 316
 317             // Get random squares for knights
 318             randIndex = _.random(7);
 319             let knight1Pos = positions[randIndex];
 320             positions.splice(randIndex, 1);
 321             randIndex = _.random(6);
 322             let knight2Pos = positions[randIndex];
 323             positions.splice(randIndex, 1);
 324
 325             // Get random square for queen
 326             randIndex = _.random(5);
 327             let queenPos = positions[randIndex];
 328             positions.splice(randIndex, 1);
 329
 330             // ...random square for marshall
 331             randIndex = _.random(4);
 332             let marshallPos = positions[randIndex];
 333             positions.splice(randIndex, 1);
 334
 335             // ...random square for cardinal
 336             randIndex = _.random(3);
 337             let cardinalPos = positions[randIndex];
 338             positions.splice(randIndex, 1);
 339
 340             // Rooks and king positions are now fixed, because of the ordering rook-king-rook
 341             let rook1Pos = positions[0];
 342             let kingPos = positions[1];
 343             let rook2Pos = positions[2];
 344
 345             // Finally put the shuffled pieces in the board array
 346             pieces[c][rook1Pos] = 'r';
 347             pieces[c][knight1Pos] = 'n';
 348             pieces[c][bishop1Pos] = 'b';
 349             pieces[c][queenPos] = 'q';
 350             pieces[c][marshallPos] = 'm';
 351             pieces[c][cardinalPos] = 'c';
 352             pieces[c][kingPos] = 'k';
 353             pieces[c][bishop2Pos] = 'b';
 354             pieces[c][knight2Pos] = 'n';
 355             pieces[c][rook2Pos] = 'r';
 356         }
 357         return pieces["b"].join("") +
 358             "/pppppppppp/10/10/10/10/10/10/PPPPPPPPPP/" +
 359             pieces["w"].join("").toUpperCase() +
 360             " w 1111 - 0000000000";
 361     }
 362 }
 363
 364 const VariantRules = GrandRules;