client/src/variants/Hiddenqueen.js

   1 import { ChessRules, PiPo, Move } from "@/base_rules";
   2 import { ArrayFun } from "@/utils/array";
   3 import { randInt } from "@/utils/alea";
   4
   5 export class HiddenqueenRules extends ChessRules {
   6   // Analyse in Hiddenqueen mode makes no sense
   7   static get CanAnalyze() {
   8     return false;
   9   }
  10
  11   static get HIDDEN_QUEEN() {
  12     return 't';
  13   }
  14
  15   static get PIECES() {
  16     return ChessRules.PIECES.concat([V.HIDDEN_QUEEN]);
  17   }
  18
  19   getPiece(i, j) {
  20     const piece = this.board[i][j].charAt(1);
  21     if (
  22       piece != V.HIDDEN_QUEEN ||
  23       // 'side' is used to determine what I see: a pawn or a (hidden)queen?
  24       this.getColor(i, j) == this.side
  25     ) {
  26       return piece;
  27     }
  28     return V.PAWN;
  29   }
  30
  31   getPpath(b, color, score) {
  32     if (b[1] == V.HIDDEN_QUEEN) {
  33       // Supposed to be hidden.
  34       if (score == "*" && (!color || color != b[0]))
  35         return b[0] + "p";
  36       return "Hiddenqueen/" + b[0] + "t";
  37     }
  38     return b;
  39   }
  40
  41   isValidPawnMove(move) {
  42     const color = move.vanish[0].c;
  43     const pawnShift = color == "w" ? -1 : 1;
  44     const startRank = color == "w" ? V.size.x - 2 : 1;
  45     return (
  46       (
  47         move.end.x - move.start.x == pawnShift &&
  48         (
  49           (
  50             // Normal move
  51             move.end.y == move.start.y &&
  52             this.board[move.end.x][move.end.y] == V.EMPTY
  53           )
  54           ||
  55           (
  56             // Capture
  57             Math.abs(move.end.y - move.start.y) == 1 &&
  58             this.board[move.end.x][move.end.y] != V.EMPTY
  59           )
  60         )
  61       )
  62       ||
  63       (
  64         // Two-spaces initial jump
  65         move.start.x == startRank &&
  66         move.end.y == move.start.y &&
  67         move.end.x - move.start.x == 2 * pawnShift &&
  68         this.board[move.end.x][move.end.y] == V.EMPTY
  69       )
  70     );
  71   }
  72
  73   getPotentialMovesFrom([x, y]) {
  74     if (this.getPiece(x, y) == V.HIDDEN_QUEEN) {
  75       const pawnMoves = this.getPotentialPawnMoves([x, y]);
  76       let queenMoves = super.getPotentialQueenMoves([x, y]);
  77       // Remove from queen moves those corresponding to a pawn move:
  78       queenMoves = queenMoves
  79         .filter(m => !this.isValidPawnMove(m))
  80         // Hidden queen is revealed if moving like a queen:
  81         .map(m => {
  82           m.appear[0].p = V.QUEEN;
  83           return m;
  84         });
  85       return pawnMoves.concat(queenMoves);
  86     }
  87     return super.getPotentialMovesFrom([x, y]);
  88   }
  89
  90   getPotentialPawnMoves([x, y]) {
  91     const piece = this.getPiece(x, y);
  92     const promotions =
  93       piece == V.PAWN
  94         ? [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN]
  95         : [V.QUEEN]; //hidden queen revealed
  96     return super.getPotentialPawnMoves([x, y], promotions);
  97   }
  98
  99   getPossibleMovesFrom(sq) {
 100     this.side = this.turn;
 101     return this.filterValid(this.getPotentialMovesFrom(sq));
 102   }
 103
 104   static GenRandInitFen(randomness) {
 105     let fen = ChessRules.GenRandInitFen(randomness);
 106     // Place hidden queens at random (always):
 107     let hiddenQueenPos = randInt(8);
 108     let pawnRank = "PPPPPPPP".split("");
 109     pawnRank[hiddenQueenPos] = "T";
 110     fen = fen.replace("PPPPPPPP", pawnRank.join(""));
 111     hiddenQueenPos = randInt(8);
 112     pawnRank = "pppppppp".split("");
 113     pawnRank[hiddenQueenPos] = "t";
 114     fen = fen.replace("pppppppp", pawnRank.join(""));
 115     return fen;
 116   }
 117
 118   postPlay(move) {
 119     super.postPlay(move);
 120     if (move.vanish.length == 2 && move.vanish[1].p == V.KING)
 121       // We took opponent king
 122       this.kingPos[this.turn] = [-1, -1];
 123   }
 124
 125   preUndo(move) {
 126     super.preUndo(move);
 127     const oppCol = this.turn;
 128     if (this.kingPos[oppCol][0] < 0)
 129       // Move takes opponent's king:
 130       this.kingPos[oppCol] = [move.vanish[1].x, move.vanish[1].y];
 131   }
 132
 133   getCurrentScore() {
 134     const color = this.turn;
 135     if (this.kingPos[color][0] < 0)
 136       // King disappeared
 137       return color == "w" ? "0-1" : "1-0";
 138     return super.getCurrentScore();
 139   }
 140
 141   // Search is biased, so not really needed to explore deeply
 142   static get SEARCH_DEPTH() {
 143     return 2;
 144   }
 145
 146   static get VALUES() {
 147     return Object.assign(
 148       { t: 9 },
 149       ChessRules.VALUES
 150     );
 151   }
 152
 153   getComputerMove() {
 154     this.side = this.turn;
 155     return super.getComputerMove();
 156   }
 157
 158   getNotation(move) {
 159     const notation = super.getNotation(move);
 160     if (notation.charAt(0) == 'T')
 161       // Do not reveal hidden queens
 162       return notation.substr(1);
 163     return notation;
 164   }
 165 };