client/src/variants/Absorption.js

   1 import { ChessRules } from "@/base_rules";
   2
   3 export class AbsorptionRules extends ChessRules {
   4
   5   getPpath(b) {
   6     if ([V.BN, V.RN, V.QN].includes(b[1])) return "Absorption/" + b;
   7     return b;
   8   }
   9
  10   // Three new pieces: rook+knight, bishop+knight and queen+knight
  11   static get RN() {
  12     // Empress
  13     return 'e';
  14   }
  15   static get BN() {
  16     // Princess
  17     return 's';
  18   }
  19   static get QN() {
  20     // Amazon
  21     return 'a';
  22   }
  23
  24   static get PIECES() {
  25     return ChessRules.PIECES.concat([V.RN, V.BN, V.QN]);
  26   }
  27
  28   static get MergeComposed() {
  29     return {
  30       "be": "a",
  31       "bs": "s",
  32       "er": "e",
  33       "rs": "a",
  34       "eq": "a",
  35       "qs": "a",
  36       "ee": "e",
  37       "es": "a",
  38       "ss": "s"
  39     };
  40   }
  41
  42   static Fusion(p1, p2) {
  43     if (p1 == V.KING) return p1;
  44     if (p1 == V.PAWN) return p2;
  45     if (p2 == V.PAWN) return p1;
  46     if ([p1, p2].includes(V.KNIGHT)) {
  47       if ([p1, p2].includes(V.QUEEN)) return V.QN;
  48       if ([p1, p2].includes(V.ROOK)) return V.RN;
  49       if ([p1, p2].includes(V.BISHOP)) return V.BN;
  50       // p1 or p2 already have knight + other piece
  51       return (p1 == V.KNIGHT ? p2 : p1);
  52     }
  53     if ([p1, p2].includes(V.QN)) return V.QN;
  54     for (let p of [p1, p2]) {
  55       if ([V.BN, V.RN].includes(p))
  56         return V.MergeComposed[[p1, p2].sort().join("")];
  57     }
  58     // bishop + rook, or queen + [bishop or rook]
  59     return V.QUEEN;
  60   }
  61
  62   getPotentialMovesFrom(sq) {
  63     let moves = [];
  64     const piece = this.getPiece(sq[0], sq[1]);
  65     switch (piece) {
  66       case V.RN:
  67         moves =
  68           super.getPotentialRookMoves(sq).concat(
  69           super.getPotentialKnightMoves(sq));
  70         break;
  71       case V.BN:
  72         moves =
  73           super.getPotentialBishopMoves(sq).concat(
  74           super.getPotentialKnightMoves(sq));
  75         break;
  76       case V.QN:
  77         moves =
  78           super.getPotentialQueenMoves(sq).concat(
  79           super.getPotentialKnightMoves(sq));
  80         break;
  81       default:
  82         moves = super.getPotentialMovesFrom(sq);
  83     }
  84     // Filter out capturing promotions (except one),
  85     // because they are all the same.
  86     moves = moves.filter(m => {
  87       return (
  88         m.vanish.length == 1 ||
  89         m.vanish[0].p != V.PAWN ||
  90         [V.PAWN, V.QUEEN].includes(m.appear[0].p)
  91       );
  92     });
  93     moves.forEach(m => {
  94       if (
  95         m.vanish.length == 2 &&
  96         m.appear.length == 1 &&
  97         piece != m.vanish[1].p
  98       ) {
  99         // Augment pieces abilities in case of captures
 100         m.appear[0].p = V.Fusion(piece, m.vanish[1].p);
 101       }
 102     });
 103     return moves;
 104   }
 105
 106   isAttacked(sq, color) {
 107     return (
 108       super.isAttacked(sq, color) ||
 109       this.isAttackedByBN(sq, color) ||
 110       this.isAttackedByRN(sq, color) ||
 111       this.isAttackedByQN(sq, color)
 112     );
 113   }
 114
 115   isAttackedByBN(sq, color) {
 116     return (
 117       this.isAttackedBySlideNJump(sq, color, V.BN, V.steps[V.BISHOP]) ||
 118       this.isAttackedBySlideNJump(
 119         sq, color, V.BN, V.steps[V.KNIGHT], 1)
 120     );
 121   }
 122
 123   isAttackedByRN(sq, color) {
 124     return (
 125       this.isAttackedBySlideNJump(sq, color, V.RN, V.steps[V.ROOK]) ||
 126       this.isAttackedBySlideNJump(
 127         sq, color, V.RN, V.steps[V.KNIGHT], 1)
 128     );
 129   }
 130
 131   isAttackedByQN(sq, color) {
 132     return (
 133       this.isAttackedBySlideNJump(
 134         sq, color, V.QN, V.steps[V.BISHOP].concat(V.steps[V.ROOK])) ||
 135       this.isAttackedBySlideNJump(
 136         sq, color, V.QN, V.steps[V.KNIGHT], 1)
 137     );
 138   }
 139
 140   static get VALUES() {
 141     return Object.assign(
 142       { a: 12, e: 7, s: 5 },
 143       ChessRules.VALUES
 144     );
 145   }
 146
 147   getNotation(move) {
 148     let notation = super.getNotation(move);
 149     if (move.vanish[0].p != V.PAWN && move.appear[0].p != move.vanish[0].p)
 150       // Fusion (not from a pawn: handled in ChessRules)
 151       notation += "=" + move.appear[0].p.toUpperCase();
 152     return notation;
 153   }
 154
 155 };