client/src/variants/Chakart.js

   1 import { ChessRules, Move, PiPo } from "@/base_rules";
   2 import { SuicideRules } from "@/variants/Suicide";
   3 import { ArrayFun } from "@/utils/array";
   4 import { randInt } from "@/utils/alea";
   5
   6 export class ChakartRules extends ChessRules {
   7   static get PawnSpecs() {
   8     return SuicideRules.PawnSpecs;
   9   }
  10
  11   static get HasCastle() {
  12     return false;
  13   }
  14
  15   static get HasEnpassant() {
  16     return false;
  17   }
  18
  19   static get CorrConfirm() {
  20     // Because of bonus effects
  21     return false;
  22   }
  23
  24   static get CanAnalyze() {
  25     return false;
  26   }
  27
  28   static get SomeHiddenMoves() {
  29     return true;
  30   }
  31
  32   hoverHighlight(x, y) {
  33     if (this.subTurn == 1) return false;
  34     const L = this.firstMove.length;
  35     const fm = this.firstMove[L-1];
  36     if (fm.end.effect != 0) return false;
  37     const deltaX = Math.abs(fm.appear[0].x - x);
  38     const deltaY = Math.abs(fm.appear[0].y - y);
  39     return (
  40       (this.board[x][y] == V.EMPTY || this.getColor(x, y) == 'a') &&
  41       (
  42         (fm.vanish[0].p == V.ROOK && deltaX == 1 && deltaY == 1) ||
  43         (fm.vanish[0].p == V.BISHOP && deltaX + deltaY == 1)
  44       )
  45     );
  46   }
  47
  48   static get IMMOBILIZE_CODE() {
  49     return {
  50       'p': 's',
  51       'r': 'u',
  52       'n': 'o',
  53       'b': 'c',
  54       'q': 't',
  55       'k': 'l'
  56     };
  57   }
  58
  59   static get IMMOBILIZE_DECODE() {
  60     return {
  61       's': 'p',
  62       'u': 'r',
  63       'o': 'n',
  64       'c': 'b',
  65       't': 'q',
  66       'l': 'k'
  67     };
  68   }
  69
  70   static get INVISIBLE_QUEEN() {
  71     return 'i';
  72   }
  73
  74   // Fictive color 'a', bomb banana mushroom egg
  75   static get BOMB() {
  76     return 'w'; //"Wario"
  77   }
  78   static get BANANA() {
  79     return 'd'; //"Donkey"
  80   }
  81   static get EGG() {
  82     return 'e';
  83   }
  84   static get MUSHROOM() {
  85     return 'm';
  86   }
  87
  88   static fen2board(f) {
  89     return (
  90       f.charCodeAt() <= 90
  91         ? "w" + f.toLowerCase()
  92         : (['w', 'd', 'e', 'm'].includes(f) ? "a" : "b") + f
  93     );
  94   }
  95
  96   static get PIECES() {
  97     return (
  98       ChessRules.PIECES.concat(
  99       Object.keys(V.IMMOBILIZE_DECODE)).concat(
 100       [V.BANANA, V.BOMB, V.EGG, V.MUSHROOM, V.INVISIBLE_QUEEN])
 101     );
 102   }
 103
 104   getPpath(b) {
 105     let prefix = "";
 106     if (
 107       b[0] == 'a' ||
 108       b[1] == V.INVISIBLE_QUEEN ||
 109       Object.keys(V.IMMOBILIZE_DECODE).includes(b[1])
 110     ) {
 111       prefix = "Chakart/";
 112     }
 113     return prefix + b;
 114   }
 115
 116   getPPpath(m) {
 117     if (!!m.promoteInto) return m.promoteInto;
 118     let piece = m.appear[0].p;
 119     if (Object.keys(V.IMMOBILIZE_DECODE).includes(piece))
 120       piece = V.IMMOBILIZE_DECODE[piece];
 121     return this.getPpath(m.appear[0].c + piece);
 122   }
 123
 124   static ParseFen(fen) {
 125     const fenParts = fen.split(" ");
 126     return Object.assign(
 127       ChessRules.ParseFen(fen),
 128       { captured: fenParts[4] }
 129     );
 130   }
 131
 132   static IsGoodFen(fen) {
 133     if (!ChessRules.IsGoodFen(fen)) return false;
 134     const captured = V.ParseFen(fen).captured;
 135     if (!captured || !captured.match(/^[0-9]{12,12}$/)) return false;
 136     return true;
 137   }
 138
 139   // King can be l or L (immobilized) --> similar to Alice variant
 140   static IsGoodPosition(position) {
 141     if (position.length == 0) return false;
 142     const rows = position.split("/");
 143     if (rows.length != V.size.x) return false;
 144     let kings = { "k": 0, "K": 0, 'l': 0, 'L': 0 };
 145     for (let row of rows) {
 146       let sumElts = 0;
 147       for (let i = 0; i < row.length; i++) {
 148         if (['K', 'k', 'L', 'l'].includes(row[i])) kings[row[i]]++;
 149         if (V.PIECES.includes(row[i].toLowerCase())) sumElts++;
 150         else {
 151           const num = parseInt(row[i]);
 152           if (isNaN(num)) return false;
 153           sumElts += num;
 154         }
 155       }
 156       if (sumElts != V.size.y) return false;
 157     }
 158     if (kings['k'] + kings['l'] == 0 || kings['K'] + kings['L'] == 0)
 159       return false;
 160     return true;
 161   }
 162
 163   static IsGoodFlags(flags) {
 164     // 4 for Peach + Mario w, b
 165     return !!flags.match(/^[01]{4,4}$/);
 166   }
 167
 168   setFlags(fenflags) {
 169     // King can send shell? Queen can be invisible?
 170     this.powerFlags = {
 171       w: { 'k': false, 'q': false },
 172       b: { 'k': false, 'q': false }
 173     };
 174     for (let c of ["w", "b"]) {
 175       for (let p of ['k', 'q']) {
 176         this.powerFlags[c][p] =
 177           fenflags.charAt((c == "w" ? 0 : 2) + (p == 'k' ? 0 : 1)) == "1";
 178       }
 179     }
 180   }
 181
 182   aggregateFlags() {
 183     return this.powerFlags;
 184   }
 185
 186   disaggregateFlags(flags) {
 187     this.powerFlags = flags;
 188   }
 189
 190   getFen() {
 191     return super.getFen() + " " + this.getCapturedFen();
 192   }
 193
 194   getFenForRepeat() {
 195     return super.getFenForRepeat() + "_" + this.getCapturedFen();
 196   }
 197
 198   getCapturedFen() {
 199     let counts = [...Array(12).fill(0)];
 200     let i = 0;
 201     for (let p of V.RESERVE_PIECES) {
 202       counts[i] = this.captured["w"][p];
 203       counts[6 + i] = this.captured["b"][p];
 204       i++;
 205     }
 206     return counts.join("");
 207   }
 208
 209   scanKings() {}
 210
 211   setOtherVariables(fen) {
 212     super.setOtherVariables(fen);
 213     const fenParsed = V.ParseFen(fen);
 214     // Initialize captured pieces' counts from FEN
 215     this.captured = {
 216       w: {
 217         [V.PAWN]: parseInt(fenParsed.captured[0]),
 218         [V.ROOK]: parseInt(fenParsed.captured[1]),
 219         [V.KNIGHT]: parseInt(fenParsed.captured[2]),
 220         [V.BISHOP]: parseInt(fenParsed.captured[3]),
 221         [V.QUEEN]: parseInt(fenParsed.captured[4]),
 222         [V.KING]: parseInt(fenParsed.captured[5])
 223       },
 224       b: {
 225         [V.PAWN]: parseInt(fenParsed.captured[6]),
 226         [V.ROOK]: parseInt(fenParsed.captured[7]),
 227         [V.KNIGHT]: parseInt(fenParsed.captured[8]),
 228         [V.BISHOP]: parseInt(fenParsed.captured[9]),
 229         [V.QUEEN]: parseInt(fenParsed.captured[10]),
 230         [V.KING]: parseInt(fenParsed.captured[11])
 231       }
 232     };
 233     this.firstMove = [];
 234     this.subTurn = 1;
 235   }
 236
 237   getFlagsFen() {
 238     let fen = "";
 239     // Add power flags
 240     for (let c of ["w", "b"])
 241       for (let p of ['k', 'q']) fen += (this.powerFlags[c][p] ? "1" : "0");
 242     return fen;
 243   }
 244
 245   getColor(i, j) {
 246     if (i >= V.size.x) return i == V.size.x ? "w" : "b";
 247     return this.board[i][j].charAt(0);
 248   }
 249
 250   getPiece(i, j) {
 251     if (i >= V.size.x) return V.RESERVE_PIECES[j];
 252     return this.board[i][j].charAt(1);
 253   }
 254
 255   getReservePpath(index, color) {
 256     return color + V.RESERVE_PIECES[index];
 257   }
 258
 259   static get RESERVE_PIECES() {
 260     return [V.PAWN, V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN, V.KING];
 261   }
 262
 263   getReserveMoves([x, y]) {
 264     const color = this.turn;
 265     const p = V.RESERVE_PIECES[y];
 266     if (this.reserve[color][p] == 0) return [];
 267     let moves = [];
 268     const start = (color == 'w' && p == V.PAWN ? 1 : 0);
 269     const end = (color == 'b' && p == V.PAWN ? 7 : 8);
 270     for (let i = start; i < end; i++) {
 271       for (let j = 0; j < V.size.y; j++) {
 272         if (
 273           this.board[i][j] == V.EMPTY ||
 274           this.getColor(i, j) == 'a' ||
 275           this.getPiece(i, j) == V.INVISIBLE_QUEEN
 276         ) {
 277           let m = this.getBasicMove({ p: p, x: i, y: j});
 278           m.start = { x: x, y: y };
 279           moves.push(m);
 280         }
 281       }
 282     }
 283     return moves;
 284   }
 285
 286   getPotentialMovesFrom([x, y]) {
 287     let moves = [];
 288     if (this.subTurn == 1) {
 289       moves = super.getPotentialMovesFrom([x, y]);
 290       const finalPieces = V.PawnSpecs.promotions;
 291       const color = this.turn;
 292       const lastRank = (color == "w" ? 0 : 7);
 293       let pMoves = [];
 294       moves.forEach(m => {
 295         if (
 296           m.appear.length > 0 &&
 297           ['p', 's'].includes(m.appear[0].p) &&
 298           m.appear[0].x == lastRank
 299         ) {
 300           for (let i = 1; i < finalPieces.length; i++) {
 301             const piece = finalPieces[i];
 302             let otherM = JSON.parse(JSON.stringify(m));
 303             otherM.appear[0].p =
 304               m.appear[0].p == V.PAWN
 305                 ? finalPieces[i]
 306                 : V.IMMOBILIZE_CODE[finalPieces[i]];
 307             pMoves.push(otherM);
 308           }
 309           // Finally alter m itself:
 310           m.appear[0].p =
 311             m.appear[0].p == V.PAWN
 312               ? finalPieces[0]
 313               : V.IMMOBILIZE_CODE[finalPieces[0]];
 314         }
 315       });
 316       Array.prototype.push.apply(moves, pMoves);
 317     }
 318     else {
 319       // Subturn == 2
 320       const L = this.firstMove.length;
 321       const fm = this.firstMove[L-1];
 322       switch (fm.end.effect) {
 323         case "kingboo":
 324           // Exchange position with any piece,
 325           // except pawns if arriving on last rank.
 326           const lastRank = { 'w': 0, 'b': 7 };
 327           const color = this.turn;
 328           const allowLastRank = (this.getPiece(x, y) != V.PAWN);
 329           for (let i=0; i<8; i++) {
 330             for (let j=0; j<8; j++) {
 331               const colIJ = this.getColor(i, j);
 332               if (
 333                 (i != x || j != y) &&
 334                 this.board[i][j] != V.EMPTY &&
 335                 colIJ != 'a'
 336               ) {
 337                 const pieceIJ = this.getPiece(i, j);
 338                 if (
 339                   (pieceIJ != V.PAWN || x != lastRank[colIJ]) &&
 340                   (allowLastRank || i != lastRank[color])
 341                 ) {
 342                   const movedUnit = new PiPo({
 343                     x: x,
 344                     y: y,
 345                     c: colIJ,
 346                     p: this.getPiece(i, j)
 347                   });
 348                   let mMove = this.getBasicMove({ x: x, y: y }, [i, j]);
 349                   mMove.appear.push(movedUnit);
 350                   moves.push(mMove);
 351                 }
 352               }
 353             }
 354           }
 355           break;
 356         case "toadette":
 357           // Resurrect a captured piece
 358           if (x >= V.size.x) moves = this.getReserveMoves([x, y]);
 359           break;
 360         case "daisy":
 361           // Play again with the same piece
 362           if (fm.appear[0].x == x && fm.appear[0].y == y)
 363             moves = super.getPotentialMovesFrom([x, y]);
 364           break;
 365       }
 366     }
 367     return moves;
 368   }
 369
 370   // Helper for getBasicMove()
 371   getRandomSquare([x, y], steps) {
 372     const color = this.turn;
 373     const validSteps = steps.filter(s => {
 374       const [i, j] = [x + s[0], y + s[1]];
 375       return (
 376         V.OnBoard(i, j) &&
 377         (this.board[i][j] == V.EMPTY || this.getColor(i, j) != color)
 378       );
 379     });
 380     if (validSteps.length == 0)
 381       // Can happen after mushroom jump
 382       return [x, y];
 383     const step = validSteps[randInt(validSteps.length)];
 384     return [x + step[0], y + step[1]];
 385   }
 386
 387   canMove([x, y], piece) {
 388     const color = this.getColor(x, y);
 389     const oppCol = V.GetOppCol(color);
 390     piece = piece || this.getPiece(x, y);
 391     if (piece == V.PAWN) {
 392       const forward = (color == 'w' ? -1 : 1);
 393       return (
 394         V.OnBoard(x + forward, y) &&
 395         (
 396           this.board[x + forward][y] != oppCol ||
 397           (
 398             V.OnBoard(x + forward, y + 1) &&
 399             this.board[x + forward][y + 1] != V.EMPTY &&
 400             this.getColor[x + forward, y + 1] == oppCol
 401           ) ||
 402           (
 403             V.OnBoard(x + forward, y - 1) &&
 404             this.board[x + forward][y - 1] != V.EMPTY &&
 405             this.getColor[x + forward, y - 1] == oppCol
 406           )
 407         )
 408       );
 409     }
 410     // Checking one step is enough:
 411     const steps =
 412       [V.KING, V.QUEEN].includes(piece)
 413         ? V.steps[V.ROOK].concat(V.steps[V.BISHOP])
 414         : V.steps[piece];
 415     for (let step of steps) {
 416       const [i, j] = [x + step[0], y + step[1]];
 417       if (
 418         V.OnBoard(i, j) &&
 419         (this.board[i][j] == V.EMPTY || this.getColor(i, j) != color)
 420       ) {
 421         return true;
 422       }
 423     }
 424     return false;
 425   }
 426
 427   // Apply mushroom, bomb or banana effect (hidden to the player).
 428   // Determine egg effect, too, and apply its first part if possible.
 429   getBasicMove_aux(psq1, sq2, tr, initMove) {
 430     const [x1, y1] = [psq1.x, psq1.y];
 431     const color1 = this.turn;
 432     const piece1 = (!!tr ? tr.p : (psq1.p || this.getPiece(x1, y1)));
 433     const oppCol = V.GetOppCol(color1);
 434     if (!sq2) {
 435       let move = {
 436         appear: [],
 437         vanish: []
 438       };
 439       // banana or bomb defines next square, or the move ends there
 440       move.appear = [
 441         new PiPo({
 442           x: x1,
 443           y: y1,
 444           c: color1,
 445           p: piece1
 446         })
 447       ];
 448       if (this.board[x1][y1] != V.EMPTY) {
 449         const initP1 = this.getPiece(x1, y1);
 450         move.vanish = [
 451           new PiPo({
 452             x: x1,
 453             y: y1,
 454             c: this.getColor(x1, y1),
 455             p: initP1
 456           })
 457         ];
 458         if ([V.BANANA, V.BOMB].includes(initP1)) {
 459           const steps = V.steps[initP1 == V.BANANA ? V.ROOK : V.BISHOP];
 460           move.next = this.getRandomSquare([x1, y1], steps);
 461         }
 462       }
 463       move.end = { x: x1, y: y1 };
 464       return move;
 465     }
 466     const [x2, y2] = [sq2[0], sq2[1]];
 467     // The move starts normally, on board:
 468     let move = super.getBasicMove([x1, y1], [x2, y2], tr);
 469     if (!!tr) move.promoteInto = tr.c + tr.p; //in case of (chomped...)
 470     const L = this.firstMove.length;
 471     if (
 472       [V.PAWN, V.KNIGHT].includes(piece1) &&
 473       !!initMove &&
 474       (this.subTurn == 1 || this.firstMove[L-1].end.effect == "daisy")
 475     ) {
 476       switch (piece1) {
 477         case V.PAWN: {
 478           const twoSquaresMove = (Math.abs(x2 - x1) == 2);
 479           const mushroomX = x1 + (twoSquaresMove ? (x2 - x1) / 2 : 0);
 480           move.appear.push(
 481             new PiPo({
 482               x: mushroomX,
 483               y: y1,
 484               c: 'a',
 485               p: V.MUSHROOM
 486             })
 487           );
 488           if (this.getColor(mushroomX, y1) == 'a') {
 489             move.vanish.push(
 490               new PiPo({
 491                 x: mushroomX,
 492                 y: y1,
 493                 c: 'a',
 494                 p: this.getPiece(mushroomX, y1)
 495               })
 496             );
 497           }
 498           break;
 499         }
 500         case V.KNIGHT: {
 501           const deltaX = Math.abs(x2 - x1);
 502           const deltaY = Math.abs(y2 - y1);
 503           let eggSquare = [
 504             x1 + (deltaX == 2 ? (x2 - x1) / 2 : 0),
 505             y1 + (deltaY == 2 ? (y2 - y1) / 2 : 0)
 506           ];
 507           if (
 508             this.board[eggSquare[0]][eggSquare[1]] != V.EMPTY &&
 509             this.getColor(eggSquare[0], eggSquare[1]) != 'a'
 510           ) {
 511             eggSquare[0] = x1;
 512             eggSquare[1] = y1;
 513           }
 514           move.appear.push(
 515             new PiPo({
 516               x: eggSquare[0],
 517               y: eggSquare[1],
 518               c: 'a',
 519               p: V.EGG
 520             })
 521           );
 522           if (this.getColor(eggSquare[0], eggSquare[1]) == 'a') {
 523             move.vanish.push(
 524               new PiPo({
 525                 x: eggSquare[0],
 526                 y: eggSquare[1],
 527                 c: 'a',
 528                 p: this.getPiece(eggSquare[0], eggSquare[1])
 529               })
 530             );
 531           }
 532           break;
 533         }
 534       }
 535     }
 536     // For (wa)luigi effect:
 537     const changePieceColor = (color) => {
 538       let pieces = [];
 539       const oppLastRank = (color == 'w' ? 7 : 0);
 540       for (let i=0; i<8; i++) {
 541         for (let j=0; j<8; j++) {
 542           if (
 543             (i != move.vanish[0].x || j != move.vanish[0].y) &&
 544             this.board[i][j] != V.EMPTY &&
 545             this.getColor(i, j) == color
 546           ) {
 547             const piece = this.getPiece(i, j);
 548             if (piece != V.KING && (piece != V.PAWN || i != oppLastRank))
 549               pieces.push({ x: i, y: j, p: piece });
 550           }
 551         }
 552       }
 553       // Special case of the current piece (still at its initial position)
 554       if (color == color1)
 555         pieces.push({ x: move.appear[0].x, y: move.appear[0].y, p: piece1 });
 556       const cp = pieces[randInt(pieces.length)];
 557       if (move.appear[0].x != cp.x || move.appear[0].y != cp.y) {
 558         move.vanish.push(
 559           new PiPo({
 560             x: cp.x,
 561             y: cp.y,
 562             c: color,
 563             p: cp.p
 564           })
 565         );
 566       }
 567       else move.appear.shift();
 568       move.appear.push(
 569         new PiPo({
 570           x: cp.x,
 571           y: cp.y,
 572           c: V.GetOppCol(color),
 573           p: cp.p
 574         })
 575       );
 576     };
 577     const applyEggEffect = () => {
 578       if (this.subTurn == 2)
 579         // No egg effects at subTurn 2
 580         return;
 581       // 1) Determine the effect (some may be impossible)
 582       let effects = ["kingboo", "koopa", "chomp", "bowser"];
 583       if (Object.values(this.captured[color1]).some(c => c >= 1))
 584         effects.push("toadette");
 585       const lastRank = { 'w': 0, 'b': 7 };
 586       let canPlayAgain = undefined;
 587       if (
 588         move.appear[0].p == V.PAWN &&
 589         move.appear[0].x == lastRank[color1]
 590       ) {
 591         // Always possible: promote into a queen, rook or king
 592         canPlayAgain = true;
 593       }
 594       else {
 595         move.end.effect = "daisy";
 596         V.PlayOnBoard(this.board, move);
 597         const square = [move.appear[0].x, move.appear[0].y];
 598         canPlayAgain = this.canMove(square, piece1);
 599         V.UndoOnBoard(this.board, move);
 600         delete move.end["effect"];
 601       }
 602       if (canPlayAgain) effects.push("daisy");
 603       if (
 604         this.board.some((b,i) =>
 605           b.some(cell => {
 606             return (
 607               cell[0] == oppCol &&
 608               cell[1] != V.KING &&
 609               (cell[1] != V.PAWN || i != lastRank[color1])
 610             );
 611           })
 612         )
 613       ) {
 614         effects.push("luigi");
 615       }
 616       if (
 617         (
 618           piece1 != V.KING &&
 619           (piece1 != V.PAWN || move.appear[0].x != lastRank[oppCol])
 620         ) ||
 621         this.board.some((b,i) =>
 622           b.some(cell => {
 623             return (
 624               cell[0] == color1 &&
 625               cell[1] != V.KING &&
 626               (cell[1] != V.PAWN || i != lastRank[oppCol])
 627             );
 628           })
 629         )
 630       ) {
 631         effects.push("waluigi");
 632       }
 633       const effect = effects[randInt(effects.length)];
 634       move.end.effect = effect;
 635       // 2) Apply it if possible
 636       if (!(["kingboo", "toadette", "daisy"].includes(effect))) {
 637         switch (effect) {
 638           case "koopa":
 639             move.appear = [];
 640             // Maybe egg effect was applied after others,
 641             // so just shift vanish array:
 642             move.vanish.shift();
 643             break;
 644           case "chomp":
 645             move.appear = [];
 646             break;
 647           case "bowser":
 648             move.appear[0].p = V.IMMOBILIZE_CODE[piece1];
 649             break;
 650           case "luigi":
 651             changePieceColor(oppCol);
 652             break;
 653           case "waluigi":
 654             changePieceColor(color1);
 655             break;
 656         }
 657       }
 658     };
 659     const applyMushroomEffect = () => {
 660       if ([V.PAWN, V.KING, V.KNIGHT].includes(piece1)) {
 661         // Just make another similar step, if possible (non-capturing)
 662         const [i, j] = [
 663           move.appear[0].x + (x2 - x1),
 664           move.appear[0].y + (y2 - y1)
 665         ];
 666         if (
 667           V.OnBoard(i, j) &&
 668           (this.board[i][j] == V.EMPTY || this.getColor(i, j) == 'a')
 669         ) {
 670           move.appear[0].x = i;
 671           move.appear[0].y = j;
 672           if (this.board[i][j] != V.EMPTY) {
 673             const object = this.getPiece(i, j);
 674             move.vanish.push(
 675               new PiPo({
 676                 x: i,
 677                 y: j,
 678                 c: 'a',
 679                 p: object
 680               })
 681             );
 682             switch (object) {
 683               case V.BANANA:
 684               case V.BOMB:
 685                 const steps = V.steps[object == V.BANANA ? V.ROOK : V.BISHOP];
 686                 move.next = this.getRandomSquare([i, j], steps);
 687                 break;
 688               case V.EGG:
 689                 applyEggEffect();
 690                 break;
 691               case V.MUSHROOM:
 692                 applyMushroomEffect();
 693                 break;
 694             }
 695           }
 696         }
 697       }
 698       else {
 699         // Queen, bishop or rook:
 700         const step = [
 701           (x2 - x1) / Math.abs(x2 - x1) || 0,
 702           (y2 - y1) / Math.abs(y2 - y1) || 0
 703         ];
 704         const next = [move.appear[0].x + step[0], move.appear[0].y + step[1]];
 705         if (
 706           V.OnBoard(next[0], next[1]) &&
 707           this.board[next[0]][next[1]] != V.EMPTY &&
 708           this.getColor(next[0], next[1]) != 'a'
 709         ) {
 710           const afterNext = [next[0] + step[0], next[1] + step[1]];
 711           if (V.OnBoard(afterNext[0], afterNext[1])) {
 712             const afterColor = this.getColor(afterNext[0], afterNext[1])
 713             if (
 714               this.board[afterNext[0]][afterNext[1]] == V.EMPTY ||
 715               afterColor != color1
 716             ) {
 717               move.appear[0].x = afterNext[0];
 718               move.appear[0].y = afterNext[1];
 719               if (this.board[afterNext[0]][afterNext[1]] != V.EMPTY) {
 720                 // The "object" could also be an opponent's piece
 721                 const object = this.getPiece(afterNext[0], afterNext[1]);
 722                 move.vanish.push(
 723                   new PiPo({
 724                     x: afterNext[0],
 725                     y: afterNext[1],
 726                     c: afterColor,
 727                     p: object
 728                   })
 729                 );
 730                 switch (object) {
 731                   case V.BANANA:
 732                   case V.BOMB:
 733                     const steps =
 734                       V.steps[object == V.BANANA ? V.ROOK : V.BISHOP];
 735                     move.next = this.getRandomSquare(
 736                       [afterNext[0], afterNext[1]], steps);
 737                     break;
 738                   case V.EGG:
 739                     applyEggEffect();
 740                     break;
 741                   case V.MUSHROOM:
 742                     applyMushroomEffect();
 743                     break;
 744                 }
 745               }
 746             }
 747           }
 748         }
 749       }
 750     };
 751     const color2 = this.getColor(x2, y2);
 752     const piece2 = this.getPiece(x2, y2);
 753     if (color2 == 'a') {
 754       switch (piece2) {
 755         case V.BANANA:
 756         case V.BOMB:
 757           const steps = V.steps[piece2 == V.BANANA ? V.ROOK : V.BISHOP];
 758           move.next = this.getRandomSquare([x2, y2], steps);
 759           break;
 760         case V.MUSHROOM:
 761           applyMushroomEffect();
 762           break;
 763         case V.EGG:
 764           if (this.subTurn == 1)
 765             // No egg effect at subTurn 2
 766             applyEggEffect();
 767           break;
 768       }
 769     }
 770     if (
 771       this.subTurn == 1 &&
 772       !move.next &&
 773       move.appear.length > 0 &&
 774       [V.ROOK, V.BISHOP].includes(piece1)
 775     ) {
 776       const finalSquare = [move.appear[0].x, move.appear[0].y];
 777       if (
 778         color2 != 'a' ||
 779         this.getColor(finalSquare[0], finalSquare[1]) != 'a' ||
 780         this.getPiece(finalSquare[0], finalSquare[1]) != V.EGG
 781       ) {
 782         const validSteps =
 783           V.steps[piece1 == V.ROOK ? V.BISHOP : V.ROOK].filter(s => {
 784             const [i, j] = [finalSquare[0] + s[0], finalSquare[1] + s[1]];
 785             return (
 786               V.OnBoard(i, j) &&
 787               (this.board[i][j] == V.EMPTY || this.getColor(i, j) == 'a')
 788             );
 789           });
 790         if (validSteps.length >= 1) {
 791           const [x, y] = [
 792             finalSquare[0] + validSteps[0][0],
 793             finalSquare[1] + validSteps[0][1]
 794           ];
 795           move.appear.push(
 796             new PiPo({
 797               x: x,
 798               y: y,
 799               c: 'a',
 800               p: (piece1 == V.ROOK ? V.BANANA : V.BOMB)
 801             })
 802           );
 803           if (this.board[x][y] != V.EMPTY) {
 804             move.vanish.push(
 805               new PiPo({ x: x, y: y, c: 'a', p: this.getPiece(x, y) }));
 806           }
 807         }
 808       }
 809     }
 810     return move;
 811   }
 812
 813   getBasicMove(psq1, sq2, tr) {
 814     let moves = [];
 815     if (Array.isArray(psq1)) psq1 = { x: psq1[0], y: psq1[1] };
 816     let m = this.getBasicMove_aux(psq1, sq2, tr, "initMove");
 817     while (!!m.next) {
 818       // Last move ended on bomb or banana, direction change
 819       V.PlayOnBoard(this.board, m);
 820       moves.push(m);
 821       m = this.getBasicMove_aux(
 822         { x: m.appear[0].x, y: m.appear[0].y }, m.next);
 823     }
 824     for (let i=moves.length-1; i>=0; i--) V.UndoOnBoard(this.board, moves[i]);
 825     moves.push(m);
 826     // Now merge moves into one
 827     let move = {};
 828     // start is wrong for Toadette moves --> it's fixed later
 829     move.start = { x: psq1.x, y: psq1.y };
 830     move.end = !!sq2 ? { x: sq2[0], y: sq2[1] } : { x: psq1.x, y: psq1.y };
 831     if (!!tr) move.promoteInto = moves[0].promoteInto;
 832     let lm = moves[moves.length-1];
 833     if (this.subTurn == 1 && !!lm.end.effect)
 834       move.end.effect = lm.end.effect;
 835     if (moves.length == 1) {
 836       move.appear = moves[0].appear;
 837       move.vanish = moves[0].vanish;
 838     }
 839     else {
 840       // Keep first vanish and last appear (if any)
 841       move.appear = lm.appear;
 842       move.vanish = moves[0].vanish;
 843       if (
 844         move.vanish.length >= 1 &&
 845         move.appear.length >= 1 &&
 846         move.vanish[0].x == move.appear[0].x &&
 847         move.vanish[0].y == move.appear[0].y
 848       ) {
 849         // Loopback on initial square:
 850         move.vanish.shift();
 851         move.appear.shift();
 852       }
 853       for (let i=1; i < moves.length - 1; i++) {
 854         for (let v of moves[i].vanish) {
 855           // Only vanishing objects, not appearing at init move
 856           if (
 857             v.c == 'a' &&
 858             (
 859               moves[0].appear.length == 1 ||
 860               moves[0].appear[1].x != v.x ||
 861               moves[0].appear[1].y != v.y
 862             )
 863           ) {
 864             move.vanish.push(v);
 865           }
 866         }
 867       }
 868       // Final vanish is our piece, but others might be relevant
 869       // (for some egg bonuses at least).
 870       for (let i=1; i < lm.vanish.length; i++) {
 871         if (
 872           lm.vanish[i].c != 'a' ||
 873           moves[0].appear.length == 1 ||
 874           moves[0].appear[1].x != lm.vanish[i].x ||
 875           moves[0].appear[1].y != lm.vanish[i].y
 876         ) {
 877           move.vanish.push(lm.vanish[i]);
 878         }
 879       }
 880     }
 881     return move;
 882   }
 883
 884   getPotentialPawnMoves([x, y]) {
 885     const color = this.turn;
 886     const oppCol = V.GetOppCol(color);
 887     const [sizeX, sizeY] = [V.size.x, V.size.y];
 888     const shiftX = V.PawnSpecs.directions[color];
 889     const firstRank = (color == "w" ? sizeX - 1 : 0);
 890     let moves = [];
 891     if (
 892       this.board[x + shiftX][y] == V.EMPTY ||
 893       this.getColor(x + shiftX, y) == 'a'
 894     ) {
 895       this.addPawnMoves([x, y], [x + shiftX, y], moves);
 896       if (
 897         [firstRank, firstRank + shiftX].includes(x) &&
 898         (
 899           this.board[x + 2 * shiftX][y] == V.EMPTY ||
 900           this.getColor(x + 2 * shiftX, y) == 'a'
 901         )
 902       ) {
 903         moves.push(this.getBasicMove({ x: x, y: y }, [x + 2 * shiftX, y]));
 904       }
 905     }
 906     for (let shiftY of [-1, 1]) {
 907       if (
 908         y + shiftY >= 0 &&
 909         y + shiftY < sizeY &&
 910         this.board[x + shiftX][y + shiftY] != V.EMPTY &&
 911         ['a', oppCol].includes(this.getColor(x + shiftX, y + shiftY))
 912       ) {
 913         this.addPawnMoves([x, y], [x + shiftX, y + shiftY], moves);
 914       }
 915     }
 916     return moves;
 917   }
 918
 919   getPotentialQueenMoves(sq) {
 920     const normalMoves = super.getPotentialQueenMoves(sq);
 921     // If flag allows it, add 'invisible movements'
 922     let invisibleMoves = [];
 923     if (this.powerFlags[this.turn][V.QUEEN]) {
 924       normalMoves.forEach(m => {
 925         if (
 926           m.appear.length == 1 &&
 927           m.vanish.length == 1 &&
 928           // Only simple non-capturing moves:
 929           m.vanish[0].c != 'a'
 930         ) {
 931           let im = JSON.parse(JSON.stringify(m));
 932           im.appear[0].p = V.INVISIBLE_QUEEN;
 933           im.end.noHighlight = true;
 934           invisibleMoves.push(im);
 935         }
 936       });
 937     }
 938     return normalMoves.concat(invisibleMoves);
 939   }
 940
 941   getPotentialKingMoves([x, y]) {
 942     let moves = super.getPotentialKingMoves([x, y]);
 943     const color = this.turn;
 944     // If flag allows it, add 'remote shell captures'
 945     if (this.powerFlags[this.turn][V.KING]) {
 946       V.steps[V.ROOK].concat(V.steps[V.BISHOP]).forEach(step => {
 947         const [nextX, nextY] = [x + step[0], y + step[1]];
 948         if (
 949           V.OnBoard(nextX, nextY) &&
 950           (
 951             this.board[nextX][nextY] == V.EMPTY ||
 952             (
 953               this.getColor(nextX, nextY) == 'a' &&
 954               [V.EGG, V.MUSHROOM].includes(this.getPiece(nextX, nextY))
 955             )
 956           )
 957         ) {
 958           let [i, j] = [x + 2 * step[0], y + 2 * step[1]];
 959           while (
 960             V.OnBoard(i, j) &&
 961             (
 962               this.board[i][j] == V.EMPTY ||
 963               (
 964                 this.getColor(i, j) == 'a' &&
 965                 [V.EGG, V.MUSHROOM].includes(this.getPiece(i, j))
 966               )
 967             )
 968           ) {
 969             i += step[0];
 970             j += step[1];
 971           }
 972           if (V.OnBoard(i, j)) {
 973             const colIJ = this.getColor(i, j);
 974             if (colIJ != color) {
 975               // May just destroy a bomb or banana:
 976               moves.push(
 977                 new Move({
 978                   start: { x: x, y: y},
 979                   end: { x: i, y: j },
 980                   appear: [],
 981                   vanish: [
 982                     new PiPo({
 983                       x: i, y: j, c: colIJ, p: this.getPiece(i, j)
 984                     })
 985                   ]
 986                 })
 987               );
 988             }
 989           }
 990         }
 991       });
 992     }
 993     return moves;
 994   }
 995
 996   getSlideNJumpMoves([x, y], steps, oneStep) {
 997     let moves = [];
 998     outerLoop: for (let step of steps) {
 999       let i = x + step[0];
1000       let j = y + step[1];
1001       while (
1002         V.OnBoard(i, j) &&
1003         (
1004           this.board[i][j] == V.EMPTY ||
1005           this.getPiece(i, j) == V.INVISIBLE_QUEEN ||
1006           (
1007             this.getColor(i, j) == 'a' &&
1008             [V.EGG, V.MUSHROOM].includes(this.getPiece(i, j))
1009           )
1010         )
1011       ) {
1012         moves.push(this.getBasicMove({ x: x, y: y }, [i, j]));
1013         if (oneStep) continue outerLoop;
1014         i += step[0];
1015         j += step[1];
1016       }
1017       if (V.OnBoard(i, j) && this.canTake([x, y], [i, j]))
1018         moves.push(this.getBasicMove({ x: x, y: y }, [i, j]));
1019     }
1020     return moves;
1021   }
1022
1023   getAllPotentialMoves() {
1024     if (this.subTurn == 1) return super.getAllPotentialMoves();
1025     let moves = [];
1026     const L = this.firstMove.length;
1027     const fm = this.firstMove[L-1];
1028     switch (fm.end.effect) {
1029       case 0:
1030         moves.push({
1031           start: { x: -1, y: -1 },
1032           end: { x: -1, y: -1 },
1033           appear: [],
1034           vanish: []
1035         });
1036         for (
1037           let step of
1038           (fm.vanish[0].p == V.ROOK ? V.steps[V.BISHOP] : V.steps[V.ROOK])
1039         ) {
1040           const [i, j] = [fm.appear[0].x + step[0], fm.appear[0].y + step[1]];
1041           if (
1042             V.OnBoard(i, j) &&
1043             (this.board[i][j] == V.EMPTY || this.getColor(i, j) == 'a')
1044           ) {
1045             let m = new Move({
1046               start: { x: -1, y: -1 },
1047               end: { x: i, y: j },
1048               appear: [
1049                 new PiPo({
1050                   x: i,
1051                   y: j,
1052                   c: 'a',
1053                   p: (fm.vanish[0].p == V.ROOK ? V.BANANA : V.BOMB)
1054                 })
1055               ],
1056               vanish: []
1057             });
1058             if (this.board[i][j] != V.EMPTY) {
1059               m.vanish.push(
1060                 new PiPo({ x: i, y: j, c: 'a', p: this.getPiece(i, j) }));
1061             }
1062             moves.push(m);
1063           }
1064         }
1065         break;
1066       case "kingboo": {
1067         const [x, y] = [fm.appear[0].x, fm.appear[0].y];
1068         for (let i=0; i<8; i++) {
1069           for (let j=0; j<8; j++) {
1070             const colIJ = this.getColor(i, j);
1071             if (
1072               i != x &&
1073               j != y &&
1074               this.board[i][j] != V.EMPTY &&
1075               colIJ != 'a'
1076             ) {
1077               const movedUnit = new PiPo({
1078                 x: x,
1079                 y: y,
1080                 c: colIJ,
1081                 p: this.getPiece(i, j)
1082               });
1083               let mMove = this.getBasicMove({ x: x, y: y }, [i, j]);
1084               mMove.appear.push(movedUnit);
1085               moves.push(mMove);
1086             }
1087           }
1088         }
1089         break;
1090       }
1091       case "toadette": {
1092         const x = V.size.x + (this.turn == 'w' ? 0 : 1);
1093         for (let y = 0; y < 8; y++)
1094           Array.prototype.push.apply(moves, this.getReserveMoves([x, y]));
1095         break;
1096       }
1097       case "daisy":
1098         moves = super.getPotentialMovesFrom([fm.appear[0].x, fm.appear[0].y]);
1099         break;
1100     }
1101     return moves;
1102   }
1103
1104   doClick(square) {
1105     const L = this.firstMove.length;
1106     const fm = (L > 0 ? this.firstMove[L-1] : null);
1107     if (
1108       isNaN(square[0]) ||
1109       this.subTurn == 1 ||
1110       !([0, "daisy"].includes(fm.end.effect))
1111     ) {
1112       return null;
1113     }
1114     const [x, y] = [square[0], square[1]];
1115     const deltaX = Math.abs(fm.appear[0].x - x);
1116     const deltaY = Math.abs(fm.appear[0].y - y);
1117     if (
1118       fm.end.effect == 0 &&
1119       (this.board[x][y] == V.EMPTY || this.getColor(x, y) == 'a') &&
1120       (
1121         (fm.vanish[0].p == V.ROOK && deltaX == 1 && deltaY == 1) ||
1122         (fm.vanish[0].p == V.BISHOP && deltaX + deltaY == 1)
1123       )
1124     ) {
1125       let m = new Move({
1126         start: { x: -1, y: -1 },
1127         end: { x: x, y: y },
1128         appear: [
1129           new PiPo({
1130             x: x,
1131             y: y,
1132             c: 'a',
1133             p: (fm.vanish[0].p == V.ROOK ? V.BANANA : V.BOMB)
1134           })
1135         ],
1136         vanish: []
1137       });
1138       if (this.board[x][y] != V.EMPTY) {
1139         m.vanish.push(
1140           new PiPo({ x: x, y: y, c: 'a', p: this.getPiece(x, y) }));
1141       }
1142       return m;
1143     }
1144     else if (
1145       fm.end.effect == "daisy" &&
1146       deltaX == 0 && deltaY == 0 &&
1147       !this.canMove([x, y])
1148     ) {
1149       // No possible move: return empty move
1150       return {
1151         start: { x: -1, y: -1 },
1152         end: { x: -1, y: -1 },
1153         appear: [],
1154         vanish: []
1155       };
1156     }
1157     return null;
1158   }
1159
1160   play(move) {
1161 //    if (!this.states) this.states = [];
1162 //    const stateFen = this.getFen();
1163 //    this.states.push(stateFen);
1164
1165     move.flags = JSON.stringify(this.aggregateFlags());
1166     V.PlayOnBoard(this.board, move);
1167     move.turn = [this.turn, this.subTurn];
1168     if ([0, "kingboo", "toadette", "daisy"].includes(move.end.effect)) {
1169       this.firstMove.push(move);
1170       this.subTurn = 2;
1171     }
1172     else {
1173       this.turn = V.GetOppCol(this.turn);
1174       this.movesCount++;
1175       this.subTurn = 1;
1176     }
1177     this.postPlay(move);
1178   }
1179
1180   postPlay(move) {
1181     if (move.end.effect == "toadette") this.reserve = this.captured;
1182     else this.reserve = undefined;
1183     const color = move.turn[0];
1184     if (move.vanish.length == 2 && move.vanish[1].c != 'a') {
1185       // Capture: update this.captured
1186       let capturedPiece = move.vanish[1].p;
1187       if (capturedPiece == V.INVISIBLE_QUEEN) capturedPiece = V.QUEEN;
1188       else if (Object.keys(V.IMMOBILIZE_DECODE).includes(capturedPiece))
1189         capturedPiece = V.IMMOBILIZE_DECODE[capturedPiece];
1190       this.captured[move.vanish[1].c][capturedPiece]++;
1191     }
1192     else if (move.vanish.length == 0) {
1193       if (move.appear.length == 0 || move.appear[0].c == 'a') return;
1194       // A piece is back on board
1195       this.captured[move.appear[0].c][move.appear[0].p]--;
1196     }
1197     if (move.appear.length == 0) {
1198       // Three cases: king "shell capture", Chomp or Koopa
1199       if (this.getPiece(move.start.x, move.start.y) == V.KING)
1200         // King remote capture:
1201         this.powerFlags[color][V.KING] = false;
1202       else if (move.end.effect == "chomp")
1203         this.captured[color][move.vanish[0].p]++;
1204     }
1205     else if (move.appear[0].p == V.INVISIBLE_QUEEN)
1206       this.powerFlags[move.appear[0].c][V.QUEEN] = false;
1207     if (this.subTurn == 2) return;
1208     if (
1209       move.turn[1] == 1 &&
1210       move.appear.length == 0 ||
1211       !(Object.keys(V.IMMOBILIZE_DECODE).includes(move.appear[0].p))
1212     ) {
1213       // Look for an immobilized piece of my color: it can now move
1214       for (let i=0; i<8; i++) {
1215         for (let j=0; j<8; j++) {
1216           if (this.board[i][j] != V.EMPTY) {
1217             const piece = this.getPiece(i, j);
1218             if (
1219               this.getColor(i, j) == color &&
1220               Object.keys(V.IMMOBILIZE_DECODE).includes(piece)
1221             ) {
1222               this.board[i][j] = color + V.IMMOBILIZE_DECODE[piece];
1223               move.wasImmobilized = [i, j];
1224             }
1225           }
1226         }
1227       }
1228     }
1229     // Also make opponent invisible queen visible again, if any
1230     const oppCol = V.GetOppCol(color);
1231     for (let i=0; i<8; i++) {
1232       for (let j=0; j<8; j++) {
1233         if (
1234           this.board[i][j] != V.EMPTY &&
1235           this.getColor(i, j) == oppCol &&
1236           this.getPiece(i, j) == V.INVISIBLE_QUEEN
1237         ) {
1238           this.board[i][j] = oppCol + V.QUEEN;
1239           move.wasInvisible = [i, j];
1240         }
1241       }
1242     }
1243   }
1244
1245   undo(move) {
1246     this.disaggregateFlags(JSON.parse(move.flags));
1247     V.UndoOnBoard(this.board, move);
1248     if ([0, "kingboo", "toadette", "daisy"].includes(move.end.effect))
1249       this.firstMove.pop();
1250     else this.movesCount--;
1251     this.turn = move.turn[0];
1252     this.subTurn = move.turn[1];
1253     this.postUndo(move);
1254
1255 //    const stateFen = this.getFen();
1256 //    if (stateFen != this.states[this.states.length-1]) debugger;
1257 //    this.states.pop();
1258   }
1259
1260   postUndo(move) {
1261     if (!!move.wasImmobilized) {
1262       const [i, j] = move.wasImmobilized;
1263       this.board[i][j] =
1264         this.getColor(i, j) + V.IMMOBILIZE_CODE[this.getPiece(i, j)];
1265     }
1266     if (!!move.wasInvisible) {
1267       const [i, j] = move.wasInvisible;
1268       this.board[i][j] = this.getColor(i, j) + V.INVISIBLE_QUEEN;
1269     }
1270     if (move.vanish.length == 2 && move.vanish[1].c != 'a') {
1271       let capturedPiece = move.vanish[1].p;
1272       if (capturedPiece == V.INVISIBLE_QUEEN) capturedPiece = V.QUEEN;
1273       else if (Object.keys(V.IMMOBILIZE_DECODE).includes(capturedPiece))
1274         capturedPiece = V.IMMOBILIZE_DECODE[capturedPiece];
1275       this.captured[move.vanish[1].c][capturedPiece]--;
1276     }
1277     else if (move.vanish.length == 0) {
1278       if (move.appear.length == 0 || move.appear[0].c == 'a') return;
1279       // A piece was back on board
1280       this.captured[move.appear[0].c][move.appear[0].p]++;
1281     }
1282     else if (move.appear.length == 0 && move.end.effect == "chomp")
1283       this.captured[move.vanish[0].c][move.vanish[0].p]--;
1284     if (move.vanish.length == 0) this.reserve = this.captured;
1285     else this.reserve = undefined;
1286   }
1287
1288   getCheckSquares() {
1289     return [];
1290   }
1291
1292   getCurrentScore() {
1293     // Find kings (not tracked in this variant)
1294     let kingThere = { w: false, b: false };
1295     for (let i=0; i<8; i++) {
1296       for (let j=0; j<8; j++) {
1297         if (
1298           this.board[i][j] != V.EMPTY &&
1299           ['k', 'l'].includes(this.getPiece(i, j))
1300         ) {
1301           kingThere[this.getColor(i, j)] = true;
1302         }
1303       }
1304     }
1305     if (!kingThere['w']) return "0-1";
1306     if (!kingThere['b']) return "1-0";
1307     if (!this.atLeastOneMove()) return (this.turn == 'w' ? "0-1" : "1-0");
1308     return "*";
1309   }
1310
1311   static GenRandInitFen(randomness) {
1312     return (
1313       SuicideRules.GenRandInitFen(randomness).slice(0, -1) +
1314       // Add Peach + Mario flags + capture counts
1315       "1111 000000000000"
1316     );
1317   }
1318
1319   filterValid(moves) {
1320     return moves;
1321   }
1322
1323   static get VALUES() {
1324     return Object.assign(
1325       {},
1326       ChessRules.VALUES,
1327       {
1328         s: 1,
1329         u: 5,
1330         o: 3,
1331         c: 3,
1332         t: 9,
1333         l: 1000,
1334         e: 0,
1335         d: 0,
1336         w: 0,
1337         m: 0
1338       }
1339     );
1340   }
1341
1342   static get SEARCH_DEPTH() {
1343     return 1;
1344   }
1345
1346   getComputerMove() {
1347     const moves = this.getAllValidMoves();
1348     // Split into "normal" and "random" moves:
1349     // (Next splitting condition is OK because cannot take self object
1350     // without a banana or bomb on the way).
1351     const deterministicMoves = moves.filter(m => {
1352       return m.vanish.every(a => a.c != 'a' || a.p == V.MUSHROOM);
1353     });
1354     const randomMoves = moves.filter(m => {
1355       return m.vanish.some(a => a.c == 'a' && a.p != V.MUSHROOM);
1356     });
1357     if (Math.random() < deterministicMoves.length / randomMoves.length)
1358       // Play a deterministic one: capture king or material if possible
1359       return super.getComputerMove(deterministicMoves);
1360     // Play a random effect move, at random:
1361     let move1 = randomMoves[randInt(randomMoves.length)];
1362     this.play(move1);
1363     let move2 = undefined;
1364     if (this.subTurn == 2) {
1365       const moves2 = this.getAllValidMoves();
1366       move2 = moves2[randInt(moves2.length)];
1367     }
1368     this.undo(move1);
1369     if (!move2) return move1;
1370     return [move1, move2];
1371   }
1372
1373   getNotation(move) {
1374     if (move.vanish.length == 0 && move.appear.length == 0) return "-";
1375     if (
1376       !move.end.effect &&
1377       move.appear.length > 0 &&
1378       move.appear[0].p == V.INVISIBLE_QUEEN
1379     ) {
1380       return "Q??";
1381     }
1382     const finalSquare = V.CoordsToSquare(move.end);
1383     // Next condition also includes Toadette placements:
1384     if (move.appear.length > 0 && move.vanish.every(a => a.c == 'a')) {
1385       const piece =
1386         move.appear[0].p != V.PAWN ? move.appear[0].p.toUpperCase() : "";
1387       return piece + "@" + finalSquare;
1388     }
1389     else if (move.appear.length == 0) {
1390       const piece = this.getPiece(move.start.x, move.start.y);
1391       if (piece == V.KING && !move.end.effect)
1392         // King remote capture
1393         return "Kx" + finalSquare;
1394       // Koopa or Chomp, or loopback after bananas, bombs & mushrooms:
1395       return (
1396         piece.toUpperCase() + "x" + finalSquare +
1397         (
1398           !!move.end.effect
1399             ? "*" + (move.end.effect == "koopa" ? "K" : "C")
1400             : ""
1401         )
1402       );
1403     }
1404     if (move.appear.length == 1 && move.vanish.length == 1) {
1405       const moveStart = move.appear[0].p.toUpperCase() + "@";
1406       if (move.appear[0].c == 'a' && move.vanish[0].c == 'a')
1407         // Bonus replacement:
1408         return moveStart + finalSquare;
1409       if (
1410         move.vanish[0].p == V.INVISIBLE_QUEEN &&
1411         move.appear[0].x == move.vanish[0].x &&
1412         move.appear[0].y == move.vanish[0].y
1413       ) {
1414         // Toadette takes invisible queen
1415         return moveStart + "Q" + finalSquare;
1416       }
1417     }
1418     if (
1419       move.appear.length == 2 &&
1420       move.vanish.length == 2 &&
1421       move.appear.every(a => a.c != 'a') &&
1422       move.vanish.every(v => v.c != 'a')
1423     ) {
1424       // King Boo exchange
1425       return move.vanish[1].p.toUpperCase() + finalSquare;
1426     }
1427     const piece = move.vanish[0].p;
1428     let notation = undefined;
1429     if (piece == V.PAWN) {
1430       // Pawn move
1431       if (move.vanish.length >= 2) {
1432         // Capture
1433         const startColumn = V.CoordToColumn(move.start.y);
1434         notation = startColumn + "x" + finalSquare;
1435       }
1436       else notation = finalSquare;
1437       if (move.appear[0].p != V.PAWN)
1438         // Promotion
1439         notation += "=" + move.appear[0].p.toUpperCase();
1440     }
1441     else {
1442       notation =
1443         piece.toUpperCase() +
1444         (move.vanish.length >= 2 ? "x" : "") +
1445         finalSquare;
1446     }
1447     if (!!move.end.effect) {
1448       switch (move.end.effect) {
1449         case "kingboo":
1450           notation += "*B";
1451           break;
1452         case "toadette":
1453           notation += "*T";
1454           break;
1455         case "daisy":
1456           notation += "*D";
1457           break;
1458         case "bowser":
1459           notation += "*M";
1460           break;
1461         case "luigi":
1462         case "waluigi":
1463           const lastAppear = move.appear[move.appear.length - 1];
1464           const effectOn =
1465             V.CoordsToSquare({ x: lastAppear.x, y : lastAppear.y });
1466           notation += "*" + move.end.effect[0].toUpperCase() + effectOn;
1467           break;
1468       }
1469     }
1470     return notation;
1471   }
1472 };