public/javascripts/variants/Crazyhouse.js

   1 class CrazyhouseRules extends ChessRules
   2 {
   3     initVariables(fen)
   4     {
   5         super.initVariables(fen);
   6         // Also init reserves (used by the interface to show landing pieces)
   7         const V = VariantRules;
   8         this.reserve =
   9         {
  10             "w":
  11             {
  12                 [V.PAWN]: 0,
  13                 [V.ROOK]: 0,
  14                 [V.KNIGHT]: 0,
  15                 [V.BISHOP]: 0,
  16                 [V.QUEEN]: 0,
  17             },
  18             "b":
  19             {
  20                 [V.PAWN]: 0,
  21                 [V.ROOK]: 0,
  22                 [V.KNIGHT]: 0,
  23                 [V.BISHOP]: 0,
  24                 [V.QUEEN]: 0,
  25             }
  26         };
  27         // May be a continuation: adjust numbers of pieces according to captures + rebirths
  28         this.moves.forEach(m => {
  29             if (m.vanish.length == 2)
  30                 this.reserve[m.appear[0].c][m.vanish[1].p]++;
  31             else if (m.vanish.length == 0)
  32                 this.reserve[m.appear[0].c][m.appear[0].p]--;
  33         });
  34     }
  35
  36     // Used by the interface:
  37     getReservePpath(color, index)
  38     {
  39         return color + VariantRules.RESERVE_PIECES[index];
  40     }
  41
  42     // Put an ordering on reserve pieces
  43     static get RESERVE_PIECES() {
  44         const V = VariantRules;
  45         return [V.PAWN,V.ROOK,V.KNIGHT,V.BISHOP,V.QUEEN];
  46     }
  47
  48     getReserveMoves([x,y])
  49     {
  50         const color = this.turn;
  51         const p = VariantRules.RESERVE_PIECES[y];
  52         if (this.reserve[color][p] == 0)
  53             return [];
  54         let moves = [];
  55         for (let i=0; i<sizeX; i++)
  56         {
  57             for (let j=0; j<sizeY; j++)
  58             {
  59                 if (this.board[i][j] != VariantRules.EMPTY)
  60                 {
  61                     let mv = new Move({
  62                         appear: [
  63                             new PiPo({
  64                                 x: i,
  65                                 y: j,
  66                                 c: color,
  67                                 p: p
  68                             })
  69                         ]
  70                     });
  71                     moves.push(mv);
  72                 }
  73             }
  74         }
  75         return moves;
  76     }
  77
  78     getPotentialMovesFrom([x,y])
  79     {
  80         const sizeX = VariantRules.size[0];
  81         if (x < sizeX)
  82             return super.getPotentialMovesFrom([x,y]);
  83         // Reserves, outside of board: x == sizeX
  84         return this.getReserveMoves([x,y]);
  85     }
  86
  87     getAllValidMoves()
  88     {
  89         let moves = super.getAllValidMoves();
  90         const color = this.turn;
  91         const sizeX = VariantRules.size[0];
  92         for (let i=0; i<VariantRules.RESERVE_PIECES.length; i++)
  93             moves = moves.concat(this.getReserveMoves([sizeX,i]));
  94         return this.filterValid(moves);
  95     }
  96
  97     atLeastOneMove()
  98     {
  99         if (!super.atLeastOneMove())
 100         {
 101             const sizeX = VariantRules.size[0];
 102             // Scan for reserve moves
 103             for (let i=0; i<VariantRules.RESERVE_PIECES.length; i++)
 104             {
 105                 let moves = this.filterValid(this.getReserveMoves([sizeX,i]));
 106                 if (moves.length > 0)
 107                     return true;
 108             }
 109             return false;
 110         }
 111         return true;
 112     }
 113
 114     updateVariables(move)
 115     {
 116         super.updateVariables(move);
 117         const color = this.turn;
 118         if (move.vanish.length==2)
 119             this.reserve[color][move.appear[0].p]++;
 120         if (move.vanish.length==0)
 121             this.reserve[color][move.appear[0].p]--;
 122     }
 123
 124     unupdateVariables(move)
 125     {
 126         super.unupdateVariables(move);
 127         const color = this.turn;
 128         if (move.vanish.length==2)
 129             this.reserve[color][move.appear[0].p]--;
 130         if (move.vanish.length==0)
 131             this.reserve[color][move.appear[0].p]++;
 132     }
 133
 134     static get SEARCH_DEPTH() { return 2; } //high branching factor
 135
 136     getNotation(move)
 137     {
 138         if (move.vanish.length > 0)
 139             return super.getNotation(move);
 140         // Rebirth:
 141         const piece =
 142             (move.appear[0].p != VariantRules.PAWN ? move.appear.p.toUpperCase() : "");
 143         const finalSquare =
 144             String.fromCharCode(97 + move.end.y) + (VariantRules.size[0]-move.end.x);
 145         return piece + "@" + finalSquare;
 146     }
 147 }