client/src/variants/Recycle.js

   1 import { ChessRules, PiPo, Move } from "@/base_rules";
   2 import { ArrayFun } from "@/utils/array";
   3
   4 export const VariantRules = class RecycleRules extends ChessRules {
   5   static IsGoodFen(fen) {
   6     if (!ChessRules.IsGoodFen(fen)) return false;
   7     const fenParsed = V.ParseFen(fen);
   8     // 5) Check reserves
   9     if (!fenParsed.reserve || !fenParsed.reserve.match(/^[0-9]{10,10}$/))
  10       return false;
  11     return true;
  12   }
  13
  14   static ParseFen(fen) {
  15     const fenParts = fen.split(" ");
  16     return Object.assign(ChessRules.ParseFen(fen), {
  17       reserve: fenParts[5],
  18     });
  19   }
  20
  21   getEpSquare(moveOrSquare) {
  22     if (typeof moveOrSquare !== "object" || move.vanish.length > 0)
  23       return super.getEpSquare(moveOrSquare);
  24     // Landing move: no en-passant
  25     return undefined;
  26   }
  27
  28   static GenRandInitFen(randomness) {
  29     return ChessRules.GenRandInitFen(randomness) + " 0000000000";
  30   }
  31
  32   getFen() {
  33     return (
  34       super.getFen() + " " + this.getReserveFen()
  35     );
  36   }
  37
  38   getFenForRepeat() {
  39     return (
  40       this.getBaseFen() + "_" +
  41       this.getTurnFen() + "_" +
  42       this.getFlagsFen() + "_" +
  43       this.getEnpassantFen() + "_" +
  44       this.getReserveFen()
  45     );
  46   }
  47
  48   getReserveFen() {
  49     let counts = new Array(10);
  50     for (
  51       let i = 0;
  52       i < V.PIECES.length - 1;
  53       i++ //-1: no king reserve
  54     ) {
  55       counts[i] = this.reserve["w"][V.PIECES[i]];
  56       counts[5 + i] = this.reserve["b"][V.PIECES[i]];
  57     }
  58     return counts.join("");
  59   }
  60
  61   setOtherVariables(fen) {
  62     super.setOtherVariables(fen);
  63     const fenParsed = V.ParseFen(fen);
  64     // Also init reserves (used by the interface to show landable pieces)
  65     this.reserve = {
  66       w: {
  67         [V.PAWN]: parseInt(fenParsed.reserve[0]),
  68         [V.ROOK]: parseInt(fenParsed.reserve[1]),
  69         [V.KNIGHT]: parseInt(fenParsed.reserve[2]),
  70         [V.BISHOP]: parseInt(fenParsed.reserve[3]),
  71         [V.QUEEN]: parseInt(fenParsed.reserve[4])
  72       },
  73       b: {
  74         [V.PAWN]: parseInt(fenParsed.reserve[5]),
  75         [V.ROOK]: parseInt(fenParsed.reserve[6]),
  76         [V.KNIGHT]: parseInt(fenParsed.reserve[7]),
  77         [V.BISHOP]: parseInt(fenParsed.reserve[8]),
  78         [V.QUEEN]: parseInt(fenParsed.reserve[9])
  79       }
  80     };
  81   }
  82
  83   getColor(i, j) {
  84     if (i >= V.size.x) return i == V.size.x ? "w" : "b";
  85     return this.board[i][j].charAt(0);
  86   }
  87
  88   getPiece(i, j) {
  89     if (i >= V.size.x) return V.RESERVE_PIECES[j];
  90     return this.board[i][j].charAt(1);
  91   }
  92
  93   // Used by the interface:
  94   getReservePpath(index, color) {
  95     return color + V.RESERVE_PIECES[index];
  96   }
  97
  98   // Ordering on reserve pieces
  99   static get RESERVE_PIECES() {
 100     return [V.PAWN, V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN];
 101   }
 102
 103   getReserveMoves([x, y]) {
 104     const color = this.turn;
 105     const p = V.RESERVE_PIECES[y];
 106     if (this.reserve[color][p] == 0) return [];
 107     let moves = [];
 108     const pawnShift = p == V.PAWN ? 1 : 0;
 109     for (let i = pawnShift; i < V.size.x - pawnShift; i++) {
 110       for (let j = 0; j < V.size.y; j++) {
 111         if (this.board[i][j] == V.EMPTY) {
 112           let mv = new Move({
 113             appear: [
 114               new PiPo({
 115                 x: i,
 116                 y: j,
 117                 c: color,
 118                 p: p
 119               })
 120             ],
 121             vanish: [],
 122             start: { x: x, y: y }, //a bit artificial...
 123             end: { x: i, y: j }
 124           });
 125           moves.push(mv);
 126         }
 127       }
 128     }
 129     return moves;
 130   }
 131
 132   getPotentialMovesFrom([x, y]) {
 133     if (x >= V.size.x) {
 134       // Reserves, outside of board: x == sizeX(+1)
 135       return this.getReserveMoves([x, y]);
 136     }
 137     // Standard moves
 138     return super.getPotentialMovesFrom([x, y]);
 139   }
 140
 141   getPotentialPawnMoves([x, y]) {
 142     const color = this.turn;
 143     let moves = [];
 144     const [sizeX, sizeY] = [V.size.x, V.size.y];
 145     const shiftX = color == "w" ? -1 : 1;
 146     const startRank = color == "w" ? sizeX - 2 : 1;
 147     const lastRank = color == "w" ? 0 : sizeX - 1;
 148
 149     // One square forward
 150     if (this.board[x + shiftX][y] == V.EMPTY) {
 151       moves.push(
 152         this.getBasicMove([x, y], [x + shiftX, y])
 153       );
 154       // Next condition because pawns on 1st rank can generally jump
 155       if (
 156         x == startRank &&
 157         this.board[x + 2 * shiftX][y] == V.EMPTY
 158       ) {
 159         // Two squares jump
 160         moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y]));
 161       }
 162     }
 163     // Captures
 164     for (let shiftY of [-1, 1]) {
 165       if (
 166         y + shiftY >= 0 &&
 167         y + shiftY < sizeY &&
 168         this.board[x + shiftX][y + shiftY] != V.EMPTY &&
 169         this.canTake([x, y], [x + shiftX, y + shiftY])
 170       ) {
 171         moves.push(
 172           this.getBasicMove([x, y], [x + shiftX, y + shiftY])
 173         );
 174       }
 175     }
 176
 177     // En passant
 178     const Lep = this.epSquares.length;
 179     const epSquare = this.epSquares[Lep - 1]; //always at least one element
 180     if (
 181       !!epSquare &&
 182       epSquare.x == x + shiftX &&
 183       Math.abs(epSquare.y - y) == 1
 184     ) {
 185       let enpassantMove = this.getBasicMove([x, y], [epSquare.x, epSquare.y]);
 186       enpassantMove.vanish.push({
 187         x: x,
 188         y: epSquare.y,
 189         p: "p",
 190         c: this.getColor(x, epSquare.y)
 191       });
 192       moves.push(enpassantMove);
 193     }
 194
 195     // Post-processing: remove falling pawns
 196     if (x + shiftX == lastRank) {
 197       moves.forEach(m => {
 198         m.appear.pop();
 199       });
 200     }
 201
 202     return moves;
 203   }
 204
 205   getAllValidMoves() {
 206     let moves = super.getAllValidMoves();
 207     const color = this.turn;
 208     for (let i = 0; i < V.RESERVE_PIECES.length; i++)
 209       moves = moves.concat(
 210         this.getReserveMoves([V.size.x + (color == "w" ? 0 : 1), i])
 211       );
 212     return this.filterValid(moves);
 213   }
 214
 215   atLeastOneMove() {
 216     if (!super.atLeastOneMove()) {
 217       // Search one reserve move
 218       for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 219         let moves = this.filterValid(
 220           this.getReserveMoves([V.size.x + (this.turn == "w" ? 0 : 1), i])
 221         );
 222         if (moves.length > 0) return true;
 223       }
 224       return false;
 225     }
 226     return true;
 227   }
 228
 229   canTake([x1, y1], [x2, y2]) {
 230     // Self-captures allowed, except for the king:
 231     return this.getPiece(x2, y2) != V.KING;
 232   }
 233
 234   updateVariables(move) {
 235     super.updateVariables(move);
 236     if (move.vanish.length == 2 && move.appear.length == 2) return; //skip castle
 237     const color = V.GetOppCol(this.turn);
 238     if (move.vanish.length == 0) {
 239       this.reserve[color][move.appear[0].p]--;
 240       return;
 241     }
 242     else if (move.vanish.length == 2 && move.vanish[1].c == color) {
 243       // Self-capture
 244       this.reserve[color][move.vanish[1].p]++;
 245     }
 246   }
 247
 248   unupdateVariables(move) {
 249     super.unupdateVariables(move);
 250     if (move.vanish.length == 2 && move.appear.length == 2) return;
 251     const color = this.turn;
 252     if (move.vanish.length == 0) {
 253       this.reserve[color][move.appear[0].p]++;
 254       return;
 255     }
 256     else if (move.vanish.length == 2 && move.vanish[1].c == color) {
 257       this.reserve[color][move.vanish[1].p]--;
 258     }
 259   }
 260
 261   static get SEARCH_DEPTH() {
 262     return 2;
 263   }
 264
 265   evalPosition() {
 266     let evaluation = super.evalPosition();
 267     // Add reserves:
 268     for (let i = 0; i < V.RESERVE_PIECES.length; i++) {
 269       const p = V.RESERVE_PIECES[i];
 270       evaluation += this.reserve["w"][p] * V.VALUES[p];
 271       evaluation -= this.reserve["b"][p] * V.VALUES[p];
 272     }
 273     return evaluation;
 274   }
 275
 276   getNotation(move) {
 277     const finalSquare = V.CoordsToSquare(move.end);
 278     if (move.vanish.length > 0) {
 279       if (move.appear.length > 0) {
 280         // Standard move
 281         return super.getNotation(move);
 282       } else {
 283         // Pawn fallen: capturing or not
 284         let res = "";
 285         if (move.vanish.length == 2)
 286           res += V.CoordToColumn(move.start.y) + "x";
 287         return res + finalSquare;
 288       }
 289     }
 290     // Rebirth:
 291     const piece =
 292       move.appear[0].p != V.PAWN ? move.appear[0].p.toUpperCase() : "";
 293     return piece + "@" + V.CoordsToSquare(move.end);
 294   }
 295 };