client/src/variants/Madrasi.js

   1 import { ChessRules } from "@/base_rules";
   2
   3 export class MadrasiRules extends ChessRules {
   4   isImmobilized(sq) {
   5     const oppCol = V.GetOppCol(this.turn);
   6     const piece = this.getPiece(sq[0], sq[1]);
   7     let steps = [];
   8     switch (piece) {
   9       // NOTE: cannot use super.isAttackedByXXX
  10       // because it would call the redefined isAttackedBySlideNJump
  11       // => Infinite recursive calls.
  12       case V.PAWN: {
  13         const forward = (oppCol == 'w' ? 1 : -1);
  14         steps = [[forward, 1], [forward, -1]];
  15         break;
  16       }
  17       case V.ROOK:
  18       case V.BISHOP:
  19       case V.KNIGHT:
  20         steps = V.steps[piece];
  21         break;
  22       case V.KING:
  23       case V.QUEEN:
  24         steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
  25         break;
  26     }
  27     return super.isAttackedBySlideNJump(
  28       sq, oppCol, piece, steps, [V.KING, V.PAWN, V.KNIGHT].includes(piece))
  29   }
  30
  31   getPotentialMovesFrom([x, y]) {
  32     return (
  33       !this.isImmobilized([x, y])
  34         ? super.getPotentialMovesFrom([x, y])
  35         : []
  36     );
  37   }
  38
  39   isAttackedBySlideNJump([x, y], color, piece, steps, oneStep) {
  40     for (let step of steps) {
  41       let rx = x + step[0],
  42           ry = y + step[1];
  43       while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
  44         rx += step[0];
  45         ry += step[1];
  46       }
  47       if (
  48         V.OnBoard(rx, ry) &&
  49         this.getPiece(rx, ry) == piece &&
  50         this.getColor(rx, ry) == color &&
  51         // If enemy is immobilized, it doesn't attack:
  52         !this.isImmobilized([rx, ry])
  53       ) {
  54         return true;
  55       }
  56     }
  57     return false;
  58   }
  59
  60   isAttackedByKing() {
  61     // Connected kings paralyze each other
  62     return false;
  63   }
  64 };