client/src/variants/Musketeer.js

   1 import { ChessRules, Move, PiPo } from "@/base_rules";
   2 import { randInt } from "@/utils/alea";
   3
   4 export class MusketeerRules extends ChessRules {
   5
   6   // Extra pieces get strange letters because many taken by combinations below
   7   static get LEOPARD() {
   8     return "d";
   9   }
  10   static get CANNON() {
  11     return "w";
  12   }
  13   static get UNICORN() {
  14     return "x";
  15   }
  16   static get ELEPHANT() {
  17     return "e";
  18   }
  19   static get HAWK() {
  20     return "h";
  21   }
  22   static get FORTRESS() {
  23     return "f";
  24   }
  25   static get SPIDER() {
  26     return "y";
  27   }
  28
  29   static get RESERVE_PIECES() {
  30     return (
  31       [V.LEOPARD, V.CANNON, V.UNICORN, V.ELEPHANT,
  32       V.HAWK, V.FORTRESS, V.SPIDER]
  33     );
  34   }
  35
  36   static get PIECES() {
  37     return ChessRules.PIECES.concat(V.RESERVE_PIECES);
  38   }
  39
  40   // Decode if normal piece, or + piece1 or piece2
  41   getPiece(i, j) {
  42     if (i >= V.size.x) return V.RESERVE_PIECES[j];
  43     const piece = this.board[i][j].charAt(1);
  44     if (V.PIECES.includes(piece)) return piece;
  45     // Augmented piece:
  46     switch (piece) {
  47       case 'a':
  48       case 'c':
  49         return 'b';
  50       case 'j':
  51       case 'l':
  52         return 'k';
  53       case 'm':
  54       case 'o':
  55         return 'n';
  56       case 's':
  57       case 't':
  58         return 'q';
  59       case 'u':
  60       case 'v':
  61         return 'r';
  62     }
  63   }
  64
  65   getColor(i, j) {
  66     if (i >= V.size.x) return i == V.size.x ? "w" : "b";
  67     return this.board[i][j].charAt(0);
  68   }
  69
  70   // Code: a/c = bishop + piece1/piece2 j/l for king,
  71   // m/o for knight, s/t for queen, u/v for rook
  72   static get AUGMENTED_PIECES() {
  73     return [
  74       'a',
  75       'c',
  76       'j',
  77       'l',
  78       'm',
  79       'o',
  80       's',
  81       't',
  82       'u',
  83       'v'
  84     ];
  85   }
  86
  87   getPpath(b) {
  88     return (ChessRules.PIECES.includes(b[1]) ? "" : "Musketeer/") + b;
  89   }
  90
  91   getReservePpath(index, color) {
  92     return "Musketeer/" + color + V.RESERVE_PIECES[index];
  93   }
  94
  95   // Decode above notation into additional piece
  96   getExtraPiece(symbol) {
  97     if (['a','j','m','s','u'].includes(symbol))
  98       return this.extraPieces[0];
  99     return this.extraPieces[1];
 100   }
 101
 102   // Inverse operation: augment piece
 103   getAugmented(piece) {
 104     const p1 = [2, 3].includes(this.movesCount);
 105     switch (piece) {
 106       case V.ROOK: return (p1 ? 'u' : 'v');
 107       case V.KNIGHT: return (p1 ? 'm' : 'o');
 108       case V.BISHOP: return (p1 ? 'a' : 'c');
 109       case V.QUEEN: return (p1 ? 's' : 't');
 110       case V.KING: return (p1 ? 'j' : 'l');
 111     }
 112     return '_'; //never reached
 113   }
 114
 115   static IsGoodFen(fen) {
 116     if (!ChessRules.IsGoodFen(fen)) return false;
 117     const fenParsed = V.ParseFen(fen);
 118     // 5) Check extra pieces
 119     if (!fenParsed.extraPieces) return false;
 120     // Not exact matching (would need to look at movesCount), but OK for now
 121     if (!fenParsed.extraPieces.match(/^[dwxejfy-]{2,2}$/)) return false;
 122     return true;
 123   }
 124
 125   static IsGoodPosition(position) {
 126     if (position.length == 0) return false;
 127     const rows = position.split("/");
 128     if (rows.length != V.size.x) return false;
 129     let kings = { "w": 0, "b": 0 };
 130     const allPiecesCodes = V.PIECES.concat(V.AUGMENTED_PIECES);
 131     const kingBlackCodes = ['j','k','l'];
 132     const kingWhiteCodes = ['J','K','L'];
 133     for (let row of rows) {
 134       let sumElts = 0;
 135       for (let i = 0; i < row.length; i++) {
 136         if (kingBlackCodes.includes(row[i])) kings['b']++;
 137         else if (kingWhiteCodes.includes(row[i])) kings['w']++;
 138         if (allPiecesCodes.includes(row[i].toLowerCase())) sumElts++;
 139         else {
 140           const num = parseInt(row[i], 10);
 141           if (isNaN(num)) return false;
 142           sumElts += num;
 143         }
 144       }
 145       if (sumElts != V.size.y) return false;
 146     }
 147     // Both kings should be on board, only one of each color:
 148     if (Object.values(kings).some(v => v != 1)) return false;
 149     return true;
 150   }
 151
 152   static ParseFen(fen) {
 153     const fenParts = fen.split(" ");
 154     return Object.assign(
 155       ChessRules.ParseFen(fen),
 156       { extraPieces: fenParts[5] }
 157     );
 158   }
 159
 160   static GenRandInitFen(randomness) {
 161     return ChessRules.GenRandInitFen(randomness) + " --";
 162   }
 163
 164   getFen() {
 165     return super.getFen() + " " + this.extraPieces.join("");
 166   }
 167
 168   setOtherVariables(fen) {
 169     super.setOtherVariables(fen);
 170     // Extra pieces may not be defined yet (thus '-')
 171     this.extraPieces = V.ParseFen(fen).extraPieces.split("");
 172     // At early stages, also init reserves
 173     if (this.movesCount <= 5) {
 174       const condShow = (piece) => {
 175         if (this.movesCount == 0) return true;
 176         if (this.movesCount == 1) return piece != this.extraPieces[0];
 177         if (this.movesCount <= 3) return this.extraPiece.includes(piece);
 178         return this.extraPiece[1] == piece;
 179       }
 180       this.reserve = { w : {}, b: {} };
 181       for (let c of ['w', 'b']) {
 182         V.RESERVE_PIECES.forEach(p =>
 183           this.reserve[c][p] = condShow(p) ? 1 : 0);
 184       }
 185     }
 186   }
 187
 188   // Kings may be augmented:
 189   scanKings(fen) {
 190     this.kingPos = { w: [-1, -1], b: [-1, -1] };
 191     const rows = V.ParseFen(fen).position.split("/");
 192     for (let i = 0; i < rows.length; i++) {
 193       let k = 0; //column index on board
 194       for (let j = 0; j < rows[i].length; j++) {
 195         const piece = rows[i].charAt(j);
 196         if (['j','k','l'].includes(piece.toLowerCase())) {
 197           const color = (piece.charCodeAt(0) <= 90 ? 'w' : 'b');
 198           this.kingPos[color] = [i, k];
 199         }
 200         else {
 201           const num = parseInt(rows[i].charAt(j), 10);
 202           if (!isNaN(num)) k += num - 1;
 203         }
 204         k++;
 205       }
 206     }
 207   }
 208
 209   getReserveMoves([x, y]) {
 210     const color = this.turn;
 211     const p = V.RESERVE_PIECES[y];
 212     if (
 213       this.reserve[color][p] == 0 ||
 214       ([2, 3].includes(this.movesCount) && p != this.extraPieces[0]) ||
 215       ([4, 5].includes(this.movesCount) && p != this.extraPieces[1])
 216     ) {
 217       return [];
 218     }
 219     let moves = [];
 220     const iIdx =
 221       (this.movesCount <= 1 ? [2, 3, 4, 5] : [color == 'w' ? 7 : 0]);
 222     const mappingAppear = [ [3, 4], [3, 3], [4, 4], [4, 3] ];
 223     for (let i of iIdx) {
 224       for (let j = 0; j < V.size.y; j++) {
 225         if (
 226           (this.movesCount <= 1 && this.board[i][j] == V.EMPTY) ||
 227           (
 228             this.movesCount >= 2 &&
 229             ChessRules.PIECES.includes(this.board[i][j].charAt(1))
 230           )
 231         ) {
 232           const [appearX, appearY] =
 233             this.movesCount <= 1
 234               ? mappingAppear[this.movesCount]
 235               : [i, j];
 236           const pOnBoard =
 237             (this.movesCount >= 2 ? this.board[i][j].charAt(1) : '');
 238           let mv = new Move({
 239             appear: [
 240               new PiPo({
 241                 x: appearX,
 242                 y: appearY,
 243                 c: color,
 244                 p: (this.movesCount <= 1 ? p : this.getAugmented(pOnBoard))
 245               })
 246             ],
 247             vanish: [],
 248             start: { x: x, y: y }, //a bit artificial...
 249             end: { x: i, y: j }
 250           });
 251           if (this.movesCount >= 2)
 252             mv.vanish.push(new PiPo({ x: i, y: j, c: color, p: pOnBoard }))
 253           moves.push(mv);
 254         }
 255       }
 256     }
 257     return moves;
 258   }
 259
 260   // Assumption: movesCount >= 6
 261   getPotentialMovesFrom([x, y]) {
 262     // Standard moves. If piece not in usual list, new piece appears.
 263     const initialPiece = this.getPiece(x, y);
 264     if (V.RESERVE_PIECES.includes(initialPiece)) {
 265       switch (initialPiece) {
 266         case V.LEOPARD: return this.getPotentialLeopardMoves([x, y]);
 267         case V.CANNON: return this.getPotentialCannonMoves([x, y]);
 268         case V.UNICORN: return this.getPotentialUnicornMoves([x, y]);
 269         case V.ELEPHANT: return this.getPotentialElephantMoves([x, y]);
 270         case V.HAWK: return this.getPotentialHawkMoves([x, y]);
 271         case V.FORTRESS: return this.getPotentialFortressMoves([x, y]);
 272         case V.SPIDER: return this.getPotentialSpiderMoves([x, y]);
 273       }
 274       return []; //never reached
 275     }
 276     // Following is mostly copy-paste from Titan Chess (TODO?)
 277     let moves = [];
 278     if (initialPiece == V.PAWN) {
 279       const promotions =
 280         ChessRules.PawnSpecs.promotions.concat(this.extraPieces);
 281       moves = super.getPotentialPawnMoves([x, y], promotions);
 282     }
 283     else moves = super.getPotentialMovesFrom([x, y]);
 284     const color = this.turn;
 285     if (
 286       ((color == 'w' && x == 7) || (color == "b" && x == 0)) &&
 287       V.AUGMENTED_PIECES.includes(this.board[x][y][1])
 288     ) {
 289       const newPiece = this.getExtraPiece(this.board[x][y][1]);
 290       moves.forEach(m => {
 291         m.appear[0].p = initialPiece;
 292         m.appear.push(
 293           new PiPo({
 294             p: newPiece,
 295             c: color,
 296             x: x,
 297             y: y
 298           })
 299         );
 300       });
 301       moves.forEach(m => {
 302         if (m.vanish.length <= 1) return;
 303         const [vx, vy] = [m.vanish[1].x, m.vanish[1].y];
 304         if (
 305           m.appear.length >= 2 && //3 if the king was also augmented
 306           m.vanish.length == 2 &&
 307           m.vanish[1].c == color &&
 308           V.AUGMENTED_PIECES.includes(this.board[vx][vy][1])
 309         ) {
 310           // Castle, rook is an "augmented piece"
 311           m.appear[1].p = V.ROOK;
 312           m.appear.push(
 313             new PiPo({
 314               p: this.getExtraPiece(this.board[vx][vy][1]),
 315               c: color,
 316               x: vx,
 317               y: vy
 318             })
 319           );
 320         }
 321       });
 322     }
 323     return moves;
 324   }
 325
 326   getSlideNJumpMoves([x, y], steps, nbSteps) {
 327     let moves = [];
 328     outerLoop: for (let step of steps) {
 329       let i = x + step[0];
 330       let j = y + step[1];
 331       let stepCounter = 1;
 332       while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
 333         moves.push(this.getBasicMove([x, y], [i, j]));
 334         if (
 335           !!nbSteps &&
 336           // Next condition to remain compatible with super method
 337           (isNaN(parseInt(nbSteps, 10)) || nbSteps >= stepCounter)
 338         ) {
 339           continue outerLoop;
 340         }
 341         i += step[0];
 342         j += step[1];
 343         stepCounter++;
 344       }
 345       if (V.OnBoard(i, j) && this.canTake([x, y], [i, j]))
 346         moves.push(this.getBasicMove([x, y], [i, j]));
 347     }
 348     return moves;
 349   }
 350
 351   // All types of leaps used here:
 352   static get Leap2Ortho() {
 353     return [ [-2, 0], [0, -2], [2, 0], [0, 2] ];
 354   }
 355   static get Leap2Diago() {
 356     return [ [-2, -2], [-2, 2], [2, -2], [2, 2] ];
 357   }
 358   static get Leap3Ortho() {
 359     return [ [-3, 0], [0, -3], [3, 0], [0, 3] ];
 360   }
 361   static get Leap3Diago() {
 362     return [ [-3, -3], [-3, 3], [3, -3], [3, 3] ];
 363   }
 364   static get CamelSteps() {
 365     return [
 366       [-3, -1], [-3, 1], [-1, -3], [-1, 3],
 367       [1, -3], [1, 3], [3, -1], [3, 1]
 368     ];
 369   }
 370   static get VerticalKnight() {
 371     return [ [-2, -1], [-2, 1], [2, -1], [2, 1] ];
 372   }
 373   static get HorizontalKnight() {
 374     return [ [-1, -2], [-1, 2], [1, -2], [1, 2] ];
 375   }
 376
 377   getPotentialLeopardMoves(sq) {
 378     return (
 379       this.getSlideNJumpMoves(sq, V.steps[V.BISHOP], 2)
 380       .concat(super.getPotentialKnightMoves(sq))
 381     );
 382   }
 383
 384   getPotentialCannonMoves(sq) {
 385     const steps =
 386       V.steps[V.ROOK].concat(V.steps[V.BISHOP])
 387       .concat(V.Leap2Ortho).concat(V.HorizontalKnight);
 388     return super.getSlideNJumpMoves(sq, steps, "oneStep");
 389   }
 390
 391   getPotentialUnicornMoves(sq) {
 392     return (
 393       super.getPotentialKnightMoves(sq)
 394       .concat(super.getSlideNJumpMoves(sq, V.CamelSteps, "oneStep"))
 395     );
 396   }
 397
 398   getPotentialElephantMoves(sq) {
 399     const steps =
 400       V.steps[V.ROOK].concat(V.steps[V.BISHOP])
 401       .concat(V.Leap2Ortho)
 402       .concat(V.Leap2Diago);
 403     return super.getSlideNJumpMoves(sq, steps, "oneStep");
 404   }
 405
 406   getPotentialHawkMoves(sq) {
 407     const steps =
 408       V.Leap2Ortho.concat(V.Leap2Diago)
 409       .concat(V.Leap3Ortho).concat(V.Leap3Diago);
 410     return super.getSlideNJumpMoves(sq, steps, "oneStep");
 411   }
 412
 413   getPotentialFortressMoves(sq) {
 414     const steps = V.Leap2Ortho.concat(V.VerticalKnight)
 415     return (
 416       super.getSlideNJumpMoves(sq, steps, "oneStep")
 417       .concat(this.getSlideNJumpMoves(sq, V.steps[V.BISHOP], 3))
 418     );
 419   }
 420
 421   getPotentialSpiderMoves(sq) {
 422     const steps = V.Leap2Ortho.concat(V.steps[V.KNIGHT])
 423     return (
 424       super.getSlideNJumpMoves(sq, steps, "oneStep")
 425       .concat(this.getSlideNJumpMoves(sq, V.steps[V.BISHOP], 2))
 426     );
 427   }
 428
 429   getPossibleMovesFrom([x, y]) {
 430     if (this.movesCount <= 5)
 431       return (x >= V.size.x ? this.getReserveMoves([x, y]) : []);
 432     return super.getPossibleMovesFrom([x, y]);
 433   }
 434
 435   getAllValidMoves() {
 436     if (this.movesCount >= 6) return super.getAllValidMoves();
 437     let moves = [];
 438     const color = this.turn;
 439     for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 440       moves = moves.concat(
 441         this.getReserveMoves([V.size.x + (color == "w" ? 0 : 1), i])
 442       );
 443     }
 444     return moves;
 445   }
 446
 447   atLeastOneMove() {
 448     if (this.movesCount <= 5) return true;
 449     return super.atLeastOneMove();
 450   }
 451
 452   isAttacked(sq, color) {
 453     if (super.isAttacked(sq, color)) return true;
 454     if (
 455       this.extraPieces.includes(V.LEOPARD) &&
 456       this.isAttackedByLeopard(sq, color)
 457     ) {
 458       return true;
 459     }
 460     if (
 461       this.extraPieces.includes(V.CANNON) &&
 462       this.isAttackedByCannon(sq, color)
 463     ) {
 464       return true;
 465     }
 466     if (
 467       this.extraPieces.includes(V.UNICORN) &&
 468       this.isAttackedByUnicorn(sq, color)
 469     ) {
 470       return true;
 471     }
 472     if (
 473       this.extraPieces.includes(V.ELEPHANT) &&
 474       this.isAttackedByElephant(sq, color)
 475     ) {
 476       return true;
 477     }
 478     if (
 479       this.extraPieces.includes(V.HAWK) &&
 480       this.isAttackedByHawk(sq, color)
 481     ) {
 482       return true;
 483     }
 484     if (
 485       this.extraPieces.includes(V.FORTRESS) &&
 486       this.isAttackedByFortress(sq, color)
 487     ) {
 488       return true;
 489     }
 490     if (
 491       this.extraPieces.includes(V.SPIDER) &&
 492       this.isAttackedBySpider(sq, color)
 493     ) {
 494       return true;
 495     }
 496     return false;
 497   }
 498
 499   // Modify because of the limiyted steps options of some of the pieces here
 500   isAttackedBySlideNJump([x, y], color, piece, steps, nbSteps) {
 501     if (!!nbSteps && isNaN(parseInt(nbSteps, 10))) nbSteps = 1;
 502     for (let step of steps) {
 503       let rx = x + step[0],
 504           ry = y + step[1];
 505       let stepCounter = 1;
 506       while (
 507         V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY &&
 508         (!nbSteps || stepCounter < nbSteps)
 509       ) {
 510         rx += step[0];
 511         ry += step[1];
 512         stepCounter++;
 513       }
 514       if (
 515         V.OnBoard(rx, ry) &&
 516         this.board[rx][ry] != V.EMPTY &&
 517         this.getPiece(rx, ry) == piece &&
 518         this.getColor(rx, ry) == color
 519       ) {
 520         return true;
 521       }
 522     }
 523     return false;
 524   }
 525
 526   isAttackedByLeopard(sq, color) {
 527     return (
 528       super.isAttackedBySlideNJump(
 529         sq, color, V.LEOPARD, V.steps[V.KNIGHT], "oneStep") ||
 530       this.isAttackedBySlideNJump(sq, color, V.LEOPARD, V.steps[V.BISHOP], 2)
 531     );
 532   }
 533
 534   isAttackedByCannon(sq, color) {
 535     const steps =
 536       V.steps[V.ROOK].concat(V.steps[V.BISHOP])
 537       .concat(V.Leap2Ortho).concat(V.HorizontalKnight);
 538     return super.isAttackedBySlideNJump(sq, color, V.CANNON, steps, "oneStep");
 539   }
 540
 541   isAttackedByUnicorn(sq, color) {
 542     const steps = V.steps[V.KNIGHT].concat(V.CamelSteps)
 543     return (
 544       super.isAttackedBySlideNJump(sq, color, V.UNICORN, steps, "oneStep")
 545     );
 546   }
 547
 548   isAttackedByElephant(sq, color) {
 549     const steps =
 550       V.steps[V.ROOK].concat(V.steps[V.BISHOP])
 551       .concat(V.Leap2Ortho)
 552       .concat(V.Leap2Diago);
 553     return (
 554       super.isAttackedBySlideNJump(sq, color, V.ELEPHANT, steps, "oneStep")
 555     );
 556   }
 557
 558   isAttackedByHawk(sq, color) {
 559     const steps =
 560       V.Leap2Ortho.concat(V.Leap2Diago)
 561       .concat(V.Leap3Ortho).concat(V.Leap3Diago);
 562     return super.isAttackedBySlideNJump(sq, color, V.HAWK, steps, "oneStep");
 563   }
 564
 565   isAttackedByFortress(sq, color) {
 566     const steps = V.Leap2Ortho.concat(V.VerticalKnight)
 567     return (
 568       super.isAttackedBySlideNJump(sq, color, V.FORTRESS, steps, "oneStep") ||
 569       this.isAttackedBySlideNJump(sq, color, V.FORTRESS, V.steps[V.BISHOP], 3)
 570     );
 571   }
 572
 573   isAttackedBySpider(sq, color) {
 574     const steps = V.Leap2Ortho.concat(V.steps[V.KNIGHT])
 575     return (
 576       super.isAttackedBySlideNJump(sq, color, V.SPIDER, steps, "oneStep") ||
 577       this.isAttackedBySlideNJump(sq, color, V.SPIDER, V.steps[V.BISHOP], 2)
 578     );
 579   }
 580
 581   getCheckSquares() {
 582     if (this.movesCount <= 6) return [];
 583     return super.getCheckSquares();
 584   }
 585
 586   // At movesCount == 0,1: show full reserves [minus chosen piece1]
 587   // At movesCount == 2,3: show reserve with only 2 selected pieces
 588   // At movesCount == 4,5: show reserve with only piece2
 589   // Then, no reserve.
 590   postPlay(move) {
 591     if (this.movesCount > 6) super.postPlay(move);
 592     else {
 593       switch (this.movesCount) {
 594         case 1:
 595           this.reserve['w'][move.appear[0].p]--;
 596           this.reserve['b'][move.appear[0].p]--;
 597           this.extraPieces[0] = move.appear[0].p;
 598           break;
 599         case 2:
 600           this.extraPieces[1] = move.appear[0].p;
 601           for (let p of V.RESERVE_PIECES) {
 602             const resVal = (this.extraPieces.includes(p) ? 1 : 0);
 603             this.reserve['w'][p] = resVal;
 604             this.reserve['b'][p] = resVal;
 605           }
 606           break;
 607         case 3:
 608           this.reserve['w'][this.extraPieces[0]]--;
 609           break;
 610         case 4:
 611           this.reserve['b'][this.extraPieces[0]]--;
 612           break;
 613         case 5:
 614           this.reserve['w'][this.extraPieces[1]]--;
 615           break;
 616         case 6:
 617           this.reserve = null;
 618           this.board[3][3] = "";
 619           this.board[3][4] = "";
 620           break;
 621       }
 622     }
 623   }
 624
 625   postUndo(move) {
 626     if (this.movesCount >= 6) super.postUndo(move);
 627     else {
 628       switch (this.movesCount) {
 629         case 0:
 630           this.reserve['w'][move.appear[0].p]++;
 631           this.reserve['b'][move.appear[0].p]++;
 632           this.extraPieces[0] = '-';
 633           break;
 634         case 1:
 635           this.extraPieces[1] = '-';
 636           for (let p of V.RESERVE_PIECES) {
 637             const resVal = (p != this.extraPieces[0] ? 1 : 0);
 638             this.reserve['w'][p] = resVal;
 639             this.reserve['b'][p] = resVal;
 640           }
 641           break;
 642         case 2:
 643           this.reserve['w'][this.extraPieces[0]]++;
 644           break;
 645         case 3:
 646           this.reserve['b'][this.extraPieces[0]]++;
 647           break;
 648         case 4:
 649           this.reserve['w'][this.extraPieces[1]]++;
 650           break;
 651         case 5:
 652           this.reserve = { w: {}, b: {} };
 653           for (let c of ['w', 'b'])
 654             V.RESERVE_PIECES.forEach(p => this.reserve[c][p] = 0);
 655           this.reserve['b'][this.extraPieces[1]] = 1;
 656           this.board[3][3] = 'b' + this.extraPieces[1];
 657           this.board[3][4] = 'w' + this.extraPieces[0];
 658           break;
 659       }
 660     }
 661   }
 662
 663   getComputerMove() {
 664     if (this.movesCount >= 6) return super.getComputerMove();
 665     // Choose a move at random
 666     const moves = this.getAllValidMoves();
 667     return moves[randInt(moves.length)];
 668   }
 669
 670   static get SEARCH_DEPTH() {
 671     return 2;
 672   }
 673
 674   evalPosition() {
 675     let evaluation = 0;
 676     for (let i = 0; i < V.size.x; i++) {
 677       for (let j = 0; j < V.size.y; j++) {
 678         if (this.board[i][j] != V.EMPTY) {
 679           const sign = this.getColor(i, j) == "w" ? 1 : -1;
 680           const piece = this.getPiece(i, j);
 681           evaluation += sign * V.VALUES[piece];
 682           const symbol = this.board[i][j][1];
 683           if (V.AUGMENTED_PIECES.includes(symbol)) {
 684             const extraPiece = this.getExtraPiece(symbol);
 685             evaluation += sign * V.VALUES[extraPiece]
 686           }
 687         }
 688       }
 689     }
 690     return evaluation;
 691   }
 692
 693   static get VALUES() {
 694     return Object.assign(
 695       {
 696         d: 6.7,
 697         w: 7.5,
 698         x: 5.6,
 699         e: 6.3,
 700         h: 5.5,
 701         f: 7.6,
 702         y: 8.15
 703       },
 704       ChessRules.VALUES
 705     );
 706   }
 707
 708   static get ExtraDictionary() {
 709     return {
 710       [V.LEOPARD]: { prefix: 'L', name: "Leopard" },
 711       [V.CANNON]: { prefix: 'C', name: "Cannon" },
 712       [V.UNICORN]: { prefix: 'U', name: "Unicorn" },
 713       [V.ELEPHANT]: { prefix: 'E', name: "Elephant" },
 714       [V.HAWK]: { prefix: 'H', name: "Hawk" },
 715       [V.FORTRESS]: { prefix: 'F', name: "Fortress" },
 716       [V.SPIDER]: { prefix: 'S', name: "Spider" }
 717     }
 718   }
 719
 720   getNotation(move) {
 721     if (this.movesCount <= 5) {
 722       if (this.movesCount <= 1)
 723         return V.ExtraDictionary[move.appear[0].p].name;
 724       // Put something on the board:
 725       return (
 726         V.ExtraDictionary[V.RESERVE_PIECES[move.start.y]].prefix +
 727         "@" + V.CoordsToSquare(move.end)
 728       );
 729     }
 730     let notation = "";
 731     if (
 732       V.AUGMENTED_PIECES.includes(move.vanish[0].p) ||
 733       (
 734         move.vanish.length >= 2 &&
 735         V.AUGMENTED_PIECES.includes(move.vanish[1].p)
 736       )
 737     ) {
 738       // Simplify move before calling super.getNotation()
 739       let smove = JSON.parse(JSON.stringify(move));
 740       if (ChessRules.PIECES.includes(move.vanish[0].p)) {
 741         // Castle with an augmented rook
 742         smove.appear.pop();
 743         smove.vanish[1].p = smove.appear[1].p;
 744       }
 745       else {
 746         // Moving an augmented piece
 747         smove.appear.pop();
 748         smove.vanish[0].p = smove.appear[0].p;
 749         if (
 750           smove.vanish.length == 2 &&
 751           smove.vanish[0].c == smove.vanish[1].c &&
 752           V.AUGMENTED_PIECES.includes(move.vanish[1].p)
 753         ) {
 754           // Castle with an augmented rook
 755           smove.appear.pop();
 756           smove.vanish[1].p = smove.appear[1].p;
 757         }
 758       }
 759       notation = super.getNotation(smove);
 760     }
 761     // Else, more common case:
 762     notation = super.getNotation(move);
 763     const pieceSymbol = notation.charAt(0).toLowerCase();
 764     if (move.vanish[0].p != V.PAWN && V.RESERVE_PIECES.includes(pieceSymbol))
 765       notation = V.ExtraDictionary[pieceSymbol].prefix + notation.substr(1);
 766     return notation;
 767   }
 768
 769 };