client/src/variants/Koth.js

   1 import { ChessRules } from "@/base_rules";
   2
   3 export class KothRules extends ChessRules {
   4   filterValid(moves) {
   5     if (moves.length == 0) return [];
   6     const color = this.turn;
   7     const oppCol = V.GetOppCol(color);
   8     return moves.filter(m => {
   9       this.play(m);
  10       // Giving check is forbidden as well:
  11       const res = !this.underCheck(color) && !this.underCheck(oppCol);
  12       this.undo(m);
  13       return res;
  14     });
  15   }
  16
  17   getCurrentScore() {
  18     // Turn has changed:
  19     const color = V.GetOppCol(this.turn);
  20     if (
  21       [3,4].includes(this.kingPos[color][0]) &&
  22       [3,4].includes(this.kingPos[color][1])
  23     ) {
  24       // The middle is reached!
  25       return color == "w" ? "1-0" : "0-1";
  26     }
  27     if (this.atLeastOneMove()) return "*";
  28     // Stalemate (will probably never happen)
  29     return "1/2";
  30   }
  31
  32   evalPosition() {
  33     // Count material:
  34     let evaluation = super.evalPosition();
  35     // Ponder with king position:
  36     return (
  37       evaluation/5 +
  38       (
  39         Math.abs(this.kingPos["w"][0] - 3.5) +
  40         Math.abs(this.kingPos["w"][1] - 3.5)
  41       ) / 2 -
  42       (
  43         Math.abs(this.kingPos["b"][0] - 3.5) +
  44         Math.abs(this.kingPos["b"][1] - 3.5)
  45       ) / 2
  46     );
  47   }
  48 };