client/src/variants/Koopa.js

   1 import { ChessRules, PiPo } from "@/base_rules";
   2
   3 export class KoopaRules extends ChessRules {
   4   static get HasEnpassant() {
   5     return false;
   6   }
   7
   8   static get STUNNED() {
   9     return ['s', 'u', 'o', 'c', 't', 'l'];
  10   }
  11
  12   static get PIECES() {
  13     return ChessRules.PIECES.concat(V.STUNNED);
  14   }
  15
  16   static ParseFen(fen) {
  17     let res = ChessRules.ParseFen(fen);
  18     const fenParts = fen.split(" ");
  19     res.stunned = fenParts[4];
  20     return res;
  21   }
  22
  23   static IsGoodFen(fen) {
  24     if (!ChessRules.IsGoodFen(fen)) return false;
  25     const fenParsed = V.ParseFen(fen);
  26     // 5) Check "stunned"
  27     if (
  28       !fenParsed.stunned ||
  29       (
  30         fenParsed.stunned != "-" &&
  31         !fenParsed.stunned.match(/^([a-h][1-8][1-4],?)*$/)
  32       )
  33     ) {
  34       return false;
  35     }
  36     return true;
  37   }
  38
  39   getPpath(b) {
  40     return (V.STUNNED.includes(b[1]) ? "Koopa/" : "") + b;
  41   }
  42
  43   getFen() {
  44     return super.getFen() + " " + this.getStunnedFen();
  45   }
  46
  47   getFenForRepeat() {
  48     return super.getFenForRepeat() + "_" + this.getStunnedFen();
  49   }
  50
  51   getStunnedFen() {
  52     const squares = Object.keys(this.stunned);
  53     if (squares.length == 0) return "-";
  54     return squares.map(square => square + this.stunned[square]).join(",");
  55   }
  56
  57   // Base GenRandInitFen() is fine because en-passant indicator will
  58   // stand for stunned indicator.
  59
  60   scanKings(fen) {
  61     this.INIT_COL_KING = { w: -1, b: -1 };
  62     // Squares of white and black king:
  63     this.kingPos = { w: [-1, -1], b: [-1, -1] };
  64     const fenRows = V.ParseFen(fen).position.split("/");
  65     const startRow = { 'w': V.size.x - 1, 'b': 0 };
  66     for (let i = 0; i < fenRows.length; i++) {
  67       let k = 0; //column index on board
  68       for (let j = 0; j < fenRows[i].length; j++) {
  69         switch (fenRows[i].charAt(j)) {
  70           case "k":
  71           case "l":
  72             this.kingPos["b"] = [i, k];
  73             this.INIT_COL_KING["b"] = k;
  74             break;
  75           case "K":
  76           case "L":
  77             this.kingPos["w"] = [i, k];
  78             this.INIT_COL_KING["w"] = k;
  79             break;
  80           default: {
  81             const num = parseInt(fenRows[i].charAt(j), 10);
  82             if (!isNaN(num)) k += num - 1;
  83           }
  84         }
  85         k++;
  86       }
  87     }
  88   }
  89
  90   setOtherVariables(fen) {
  91     super.setOtherVariables(fen);
  92     let stunnedArray = [];
  93     const stunnedFen = V.ParseFen(fen).stunned;
  94     if (stunnedFen != "-") {
  95       stunnedArray =
  96         stunnedFen
  97         .split(",")
  98         .map(s => {
  99           return {
 100             square: s.substr(0, 2),
 101             state: parseInt(s[2], 10)
 102           };
 103         });
 104     }
 105     this.stunned = {};
 106     stunnedArray.forEach(s => {
 107       this.stunned[s.square] = s.state;
 108     });
 109   }
 110
 111   getNormalizedStep(step) {
 112     const [deltaX, deltaY] = [Math.abs(step[0]), Math.abs(step[1])];
 113     if (deltaX == 0 || deltaY == 0 || deltaX == deltaY)
 114       return [step[0] / deltaX || 0, step[1] / deltaY || 0];
 115     // Knight:
 116     const divisor = Math.min(deltaX, deltaY)
 117     return [step[0] / divisor, step[1] / divisor];
 118   }
 119
 120   getPotentialMovesFrom([x, y]) {
 121     let moves = super.getPotentialMovesFrom([x, y]);
 122     // Complete moves: stuns & kicks
 123     let promoteAfterStun = [];
 124     const color = this.turn;
 125     moves.forEach(m => {
 126       if (m.vanish.length == 2 && m.appear.length == 1) {
 127         const step =
 128           this.getNormalizedStep([m.end.x - m.start.x, m.end.y - m.start.y]);
 129         // "Capture" something: is target stunned?
 130         if (V.STUNNED.includes(m.vanish[1].p)) {
 131           // Kick it: continue movement in the same direction,
 132           // destroying all on its path.
 133           let [i, j] = [m.end.x + step[0], m.end.y + step[1]];
 134           while (V.OnBoard(i, j)) {
 135             if (this.board[i][j] != V.EMPTY) {
 136               m.vanish.push(
 137                 new PiPo({
 138                   x: i,
 139                   y: j,
 140                   c: this.getColor(i, j),
 141                   p: this.getPiece(i, j)
 142                 })
 143               );
 144             }
 145             i += step[0];
 146             j += step[1];
 147           }
 148         }
 149         else {
 150           // The piece is now stunned
 151           m.appear.push(JSON.parse(JSON.stringify(m.vanish[1])));
 152           const pIdx = ChessRules.PIECES.findIndex(p => p == m.appear[1].p);
 153           m.appear[1].p = V.STUNNED[pIdx];
 154           // And the capturer continue in the same direction until an empty
 155           // square or the edge of the board, maybe stunning other pieces.
 156           let [i, j] = [m.end.x + step[0], m.end.y + step[1]];
 157           while (V.OnBoard(i, j) && this.board[i][j] != V.EMPTY) {
 158             const colIJ = this.getColor(i, j);
 159             const pieceIJ = this.getPiece(i, j);
 160             let pIdx = ChessRules.PIECES.findIndex(p => p == pieceIJ);
 161             if (pIdx >= 0) {
 162               // The piece isn't already stunned
 163               m.vanish.push(
 164                 new PiPo({
 165                   x: i,
 166                   y: j,
 167                   c: colIJ,
 168                   p: pieceIJ
 169                 })
 170               );
 171               m.appear.push(
 172                 new PiPo({
 173                   x: i,
 174                   y: j,
 175                   c: colIJ,
 176                   p: V.STUNNED[pIdx]
 177                 })
 178               );
 179             }
 180             i += step[0];
 181             j += step[1];
 182           }
 183           if (V.OnBoard(i, j)) {
 184             m.appear[0].x = i;
 185             m.appear[0].y = j;
 186             // Is it a pawn on last rank?
 187             if (
 188               m.appear[0].p == V.PAWN &&
 189               ((color == 'w' && i == 0) || (color == 'b' && i == 7))
 190             ) {
 191               m.appear[0].p = V.ROOK;
 192               for (let ppiece of [V.KNIGHT, V.BISHOP, V.QUEEN]) {
 193                 let mp = JSON.parse(JSON.stringify(m));
 194                 mp.appear[0].p = ppiece;
 195                 promoteAfterStun.push(mp);
 196               }
 197             }
 198           }
 199           else
 200             // The piece is out
 201             m.appear.shift();
 202         }
 203       }
 204     });
 205     return moves.concat(promoteAfterStun);
 206   }
 207
 208   filterValid(moves) {
 209     // Forbid kicking own king out
 210     const color = this.turn;
 211     return moves.filter(m => {
 212       const kingAppear = m.appear.some(a => a.c == color && a.p == V.KING);
 213       return m.vanish.every(v => {
 214         return (
 215           v.c != color ||
 216           !["k", "l"].includes(v.p) ||
 217           (v.p == "k" && kingAppear)
 218         );
 219       });
 220     });
 221   }
 222
 223   getCheckSquares() {
 224     return [];
 225   }
 226
 227   getCurrentScore() {
 228     if (this.kingPos['w'][0] < 0) return "0-1";
 229     if (this.kingPos['b'][0] < 0) return "1-0";
 230     if (!this.atLeastOneMove()) return "1/2";
 231     return "*";
 232   }
 233
 234   postPlay(move) {
 235     // Base method is fine because a stunned king (which won't be detected)
 236     // can still castle after going back to normal.
 237     super.postPlay(move);
 238     const kIdx = move.vanish.findIndex(v => v.p == "l");
 239     if (kIdx >= 0)
 240       // A stunned king vanish (game over)
 241       this.kingPos[move.vanish[kIdx].c] = [-1, -1];
 242     move.stunned = JSON.stringify(this.stunned);
 243     // Array of stunned stage 1 pieces (just back to normal then)
 244     Object.keys(this.stunned).forEach(square => {
 245       // All (formerly) stunned pieces progress by 1 level, if still on board
 246       const coords = V.SquareToCoords(square);
 247       const [x, y] = [coords.x, coords.y];
 248       if (V.STUNNED.includes(this.board[x][y][1])) {
 249         // Stunned piece still on board
 250         this.stunned[square]--;
 251         if (this.stunned[square] == 0) {
 252           delete this.stunned[square];
 253           const color = this.getColor(x, y);
 254           const piece = this.getPiece(x, y);
 255           const pIdx = V.STUNNED.findIndex(p => p == piece);
 256           this.board[x][y] = color + ChessRules.PIECES[pIdx];
 257         }
 258       }
 259       else delete this.stunned[square];
 260     });
 261     // Any new stunned pieces?
 262     move.appear.forEach(a => {
 263       if (V.STUNNED.includes(a.p))
 264         // Set to maximum stun level:
 265         this.stunned[V.CoordsToSquare({ x: a.x, y: a.y })] = 4;
 266     });
 267   }
 268
 269   postUndo(move) {
 270     super.postUndo(move);
 271     const kIdx = move.vanish.findIndex(v => v.p == "l");
 272     if (kIdx >= 0) {
 273       // A stunned king vanished
 274       this.kingPos[move.vanish[kIdx].c] =
 275         [move.vanish[kIdx].x, move.vanish[kIdx].y];
 276     }
 277     this.stunned = JSON.parse(move.stunned);
 278     for (let i=0; i<8; i++) {
 279       for (let j=0; j<8; j++) {
 280         const square = V.CoordsToSquare({ x: i, y: j });
 281         const pieceIJ = this.getPiece(i, j);
 282         if (!this.stunned[square]) {
 283           const pIdx = V.STUNNED.findIndex(p => p == pieceIJ);
 284           if (pIdx >= 0)
 285             this.board[i][j] = this.getColor(i, j) + ChessRules.PIECES[pIdx];
 286         }
 287         else {
 288           const pIdx = ChessRules.PIECES.findIndex(p => p == pieceIJ);
 289           if (pIdx >= 0)
 290             this.board[i][j] = this.getColor(i, j) + V.STUNNED[pIdx];
 291         }
 292       }
 293     }
 294   }
 295
 296   static get VALUES() {
 297     return Object.assign(
 298       {
 299         s: 1,
 300         u: 5,
 301         o: 3,
 302         c: 3,
 303         t: 9,
 304         l: 1000
 305       },
 306       ChessRules.VALUES
 307     );
 308   }
 309
 310   static get SEARCH_DEPTH() {
 311     return 2;
 312   }
 313
 314   getNotation(move) {
 315     if (
 316       move.appear.length == 2 &&
 317       move.vanish.length == 2 &&
 318       move.appear.concat(move.vanish).every(
 319         av => ChessRules.PIECES.includes(av.p)) &&
 320       move.appear[0].p == V.KING
 321     ) {
 322       if (move.end.y < move.start.y) return "0-0-0";
 323       return "0-0";
 324     }
 325     const finalSquare = V.CoordsToSquare(move.end);
 326     const piece = this.getPiece(move.start.x, move.start.y);
 327     const captureMark = move.vanish.length >= 2 ? "x" : "";
 328     let pawnMark = "";
 329     if (piece == 'p' && captureMark.length == 1)
 330       pawnMark = V.CoordToColumn(move.start.y); //start column
 331     // Piece or pawn movement
 332     let notation =
 333       (piece == V.PAWN ? pawnMark : piece.toUpperCase()) +
 334       captureMark + finalSquare;
 335     if (
 336       piece == 'p' &&
 337       move.appear[0].c == move.vanish[0].c &&
 338       move.appear[0].p != 'p'
 339     ) {
 340       // Promotion
 341       notation += "=" + move.appear[0].p.toUpperCase();
 342     }
 343     return notation;
 344   }
 345 };