variants/Suction/class.js

   1 import ChessRules from "/base_rules.js";
   2 import {FenUtil} from "/utils/setupPieces.js";
   3 import PiPo from "/utils/PiPo.js";
   4 import Move from "/utils/Move.js";
   5
   6 export default class SuctionRules extends ChessRules {
   7
   8   static get Options() {
   9     return {
  10       select: C.Options.select,
  11       styles: [
  12         "balance",
  13         "capture",
  14         "cylinder",
  15         "dark",
  16         "doublemove",
  17         "madrasi",
  18         "progressive",
  19         "teleport"
  20       ]
  21     };
  22   }
  23
  24   get pawnPromotions() {
  25     return ['p']; //no promotions
  26   }
  27
  28   get hasFlags() {
  29     return false;
  30   }
  31
  32   setOtherVariables(fenParsed) {
  33     super.setOtherVariables(fenParsed);
  34     this.cmove = null;
  35     const cmove_str = fenParsed.cmove;
  36     if (cmove_str != "-") {
  37       this.cmove = {
  38         start: C.SquareToCoords(cmove_str.substr(0, 2)),
  39         end: C.SquareToCoords(cmove_str.substr(2))
  40       };
  41     }
  42   }
  43
  44   genRandInitBaseFen() {
  45     const s = FenUtil.setupPieces(
  46       ['r', 'n', 'b', 'q', 'k', 'b', 'n', 'r'], {diffCol: ['b']});
  47     return {
  48       fen: s.b.join("") + "/pppppppp/8/8/8/8/PPPPPPPP/" +
  49            s.w.join("").toUpperCase(),
  50       o: {}
  51     };
  52   }
  53
  54   getPartFen(o) {
  55     let parts = super.getPartFen(o);
  56     const cmoveFen = o.init || !this.cmove
  57       ? "-"
  58       : C.CoordsToSquare(this.cmove.start) + C.CoordsToSquare(this.cmove.end);
  59     parts["cmove"] = cmoveFen;
  60     return parts;
  61   }
  62
  63   getBasicMove([sx, sy], [ex, ey]) {
  64     let move = super.getBasicMove([sx, sy], [ex, ey]);
  65     if (move.vanish.length == 2) {
  66       move.appear.push(
  67         new PiPo({
  68           x: sx,
  69           y: sy,
  70           c: move.vanish[1].c,
  71           p: move.vanish[1].p
  72         })
  73       );
  74     }
  75     return move;
  76   }
  77
  78   canIplay(x, y) {
  79     return this.getPiece(x, y) != 'k' && super.canIplay(x, y);
  80   }
  81
  82   // Does m2 un-do m1 ? (to disallow undoing captures)
  83   oppositeMoves(m1, m2) {
  84     return (
  85       !!m1 &&
  86       m2.vanish.length == 2 &&
  87       m1.start.x == m2.start.x &&
  88       m1.end.x == m2.end.x &&
  89       m1.start.y == m2.start.y &&
  90       m1.end.y == m2.end.y
  91     );
  92   }
  93
  94   filterValid(moves) {
  95     return moves.filter(m => !this.oppositeMoves(this.cmove, m));
  96   }
  97
  98   postPlay(move) {
  99     super.postPlay(move);
 100     this.cmove =
 101       (move.vanish.length == 2 ? {start: move.start, end: move.end} : null);
 102   }
 103
 104   atLeastOneMove() {
 105     return true;
 106   }
 107
 108   getCurrentScore() {
 109     const color = this.turn;
 110     const kingPos = super.searchKingPos(color);
 111     if (color == "w" && kingPos[0][0] == 0) return "0-1";
 112     if (color == "b" && kingPos[0][0] == this.size.x - 1) return "1-0";
 113     // King is not on the opposite edge: game not over
 114     return "*";
 115   }
 116
 117   // Better animation for swaps
 118   customAnimate(move, segments, cb) {
 119     if (move.vanish.length < 2)
 120       return 0;
 121     super.animateMoving(move.end, move.start, null,
 122                         segments.reverse().map(s => s.reverse()), cb);
 123     return 1;
 124   }
 125
 126 };