variants/Checkless/class.js

   1 import ChessRules from "/base_rules.js";
   2
   3 export default class ChecklessRules extends ChessRules {
   4
   5   // Cannot use super.atLeastOneMove: lead to infinite recursion
   6   atLeastOneMove_aux(kingPos, oppKingPos, color, oppCol) {
   7     for (let i = 0; i < this.size.x; i++) {
   8       for (let j = 0; j < this.size.y; j++) {
   9         if (this.getColor(i, j) == color) {
  10           const moves = this.getPotentialMovesFrom([i, j]);
  11           for (let m of moves) {
  12             this.playOnBoard(m);
  13             const res = this.trackKingWrap(m, kingPos, (kp) => {
  14               return !this.underCheck(kp, [oppCol]);
  15             });
  16             this.undoOnBoard(m);
  17             if (res)
  18               return true;
  19           }
  20         }
  21       }
  22     }
  23     return false;
  24   }
  25
  26   filterValid(moves) {
  27     const fmoves = super.filterValid(moves);
  28     // Filter out moves giving check but not checkmate
  29     const color = this.turn;
  30     const oppCol = C.GetOppTurn(color);
  31     let kingPos = this.searchKingPos(color),
  32         oppKingPos = this.searchKingPos(oppCol);
  33     return fmoves.filter(m => {
  34       this.playOnBoard(m);
  35       const res = this.trackKingWrap(m, oppKingPos, (oppKp) => {
  36         return (
  37           !this.underCheck(oppKp, [color]) ||
  38           !this.atLeastOneMove_aux(oppKp, kingPos, oppCol, color)
  39         );
  40       });
  41       this.undoOnBoard(m);
  42       return res;
  43     });
  44   }
  45
  46 };