client/src/variants/Alapo.js

   1 import { ChessRules } from "@/base_rules";
   2 import { ArrayFun } from "@/utils/array";
   3 import { randInt } from "@/utils/alea";
   4
   5 export class AlapoRules extends ChessRules {
   6
   7   static get HasFlags() {
   8     return false;
   9   }
  10
  11   static get HasEnpassant() {
  12     return false;
  13   }
  14
  15   static get Lines() {
  16     return [
  17       [[1, 0], [1, 6]],
  18       [[5, 0], [5, 6]]
  19     ];
  20   }
  21
  22   static get PIECES() {
  23     return [V.ROOK, V.BISHOP, V.QUEEN, V.ROOK_S, V.BISHOP_S, V.QUEEN_S];
  24   }
  25
  26   static get ROOK_S() {
  27     return "t";
  28   }
  29   static get BISHOP_S() {
  30     return "c";
  31   }
  32   static get QUEEN_S() {
  33     return "s";
  34   }
  35
  36   getPotentialMinirookMoves(sq) {
  37     return super.getSlideNJumpMoves(sq, V.steps[V.ROOK], 1);
  38   }
  39   getPotentialMinibishopMoves(sq) {
  40     return super.getSlideNJumpMoves(sq, V.steps[V.BISHOP], 1);
  41   }
  42   getPotentialMiniqueenMoves(sq) {
  43     return super.getSlideNJumpMoves(
  44       sq, V.steps[V.ROOK].concat(V.steps[V.BISHOP]), 1);
  45   }
  46
  47   getPotentialMovesFrom(sq) {
  48     switch (this.getPiece(sq[0], sq[1])) {
  49       case V.ROOK: return super.getPotentialRookMoves(sq);
  50       case V.BISHOP: return super.getPotentialBishopMoves(sq);
  51       case V.QUEEN: return super.getPotentialQueenMoves(sq);
  52       case V.ROOK_S: return this.getPotentialMinirookMoves(sq);
  53       case V.BISHOP_S: return this.getPotentialMinibishopMoves(sq);
  54       case V.QUEEN_S: return this.getPotentialMiniqueenMoves(sq);
  55     }
  56     return [];
  57   }
  58
  59   static get size() {
  60     return { x: 6, y: 6 };
  61   }
  62
  63   getPpath(b, color, score, orientation) {
  64     // 'i' for "inversed":
  65     const suffix = (b[0] == orientation ? "" : "i");
  66     return "Alapo/" + b + suffix;
  67   }
  68
  69   static GenRandInitFen(options) {
  70     if (options.randomness == 0)
  71       return "rbqqbr/tcssct/6/6/TCSSCT/RBQQBR w 0";
  72
  73     const piece2pawn = {
  74       r: 't',
  75       q: 's',
  76       b: 'c'
  77     };
  78
  79     let pieces = { w: new Array(6), b: new Array(6) };
  80     // Shuffle pieces on first (and last rank if randomness == 2)
  81     for (let c of ["w", "b"]) {
  82       if (c == 'b' && options.randomness == 1) {
  83         pieces['b'] = pieces['w'];
  84         break;
  85       }
  86
  87       let positions = ArrayFun.range(6);
  88
  89       // Get random squares for bishops
  90       let randIndex = 2 * randInt(3);
  91       const bishop1Pos = positions[randIndex];
  92       let randIndex_tmp = 2 * randInt(3) + 1;
  93       const bishop2Pos = positions[randIndex_tmp];
  94       positions.splice(Math.max(randIndex, randIndex_tmp), 1);
  95       positions.splice(Math.min(randIndex, randIndex_tmp), 1);
  96
  97       // Get random square for queens
  98       randIndex = randInt(4);
  99       const queen1Pos = positions[randIndex];
 100       positions.splice(randIndex, 1);
 101       randIndex = randInt(3);
 102       const queen2Pos = positions[randIndex];
 103       positions.splice(randIndex, 1);
 104
 105       // Rooks positions are now fixed,
 106       const rook1Pos = positions[0];
 107       const rook2Pos = positions[1];
 108
 109       pieces[c][rook1Pos] = "r";
 110       pieces[c][bishop1Pos] = "b";
 111       pieces[c][queen1Pos] = "q";
 112       pieces[c][queen2Pos] = "q";
 113       pieces[c][bishop2Pos] = "b";
 114       pieces[c][rook2Pos] = "r";
 115     }
 116
 117     return (
 118       pieces["b"].join("") + "/" +
 119       pieces["b"].map(p => piece2pawn[p]).join("") +
 120       "/6/6/" +
 121       pieces["w"].map(p => piece2pawn[p].toUpperCase()).join("") + "/" +
 122       pieces["w"].join("").toUpperCase() +
 123       " w 0"
 124     );
 125   }
 126
 127   static IsGoodPosition(position) {
 128     if (position.length == 0) return false;
 129     const rows = position.split("/");
 130     if (rows.length != V.size.x) return false;
 131     // Just check that at least one piece of each color is there:
 132     let pieces = { "w": 0, "b": 0 };
 133     for (let row of rows) {
 134       let sumElts = 0;
 135       for (let i = 0; i < row.length; i++) {
 136         const lowerRi = row[i].toLowerCase();
 137         if (V.PIECES.includes(lowerRi)) {
 138           pieces[row[i] == lowerRi ? "b" : "w"]++;
 139           sumElts++;
 140         }
 141         else {
 142           const num = parseInt(row[i], 10);
 143           if (isNaN(num)) return false;
 144           sumElts += num;
 145         }
 146       }
 147       if (sumElts != V.size.y) return false;
 148     }
 149     if (Object.values(pieces).some(v => v == 0)) return false;
 150     return true;
 151   }
 152
 153   // Find possible captures by opponent on [x, y]
 154   findCaptures([x, y]) {
 155     const color = this.getColor(x, y);
 156     let moves = [];
 157     const steps = V.steps[V.ROOK].concat(V.steps[V.BISHOP]);
 158     const oppCol = V.GetOppCol(color);
 159     for (let loop = 0; loop < steps.length; loop++) {
 160       const step = steps[loop];
 161       let i = x + step[0];
 162       let j = y + step[1];
 163       let stepsAfter = 1;
 164       while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) {
 165         i += step[0];
 166         j += step[1];
 167         stepsAfter++;
 168       }
 169       if (
 170         V.OnBoard(i, j) &&
 171         this.board[i][j] != V.EMPTY &&
 172         this.getColor(i, j) == oppCol
 173       ) {
 174         const oppPiece = this.getPiece(i, j);
 175         if (
 176           (
 177             stepsAfter >= 2 &&
 178             [V.ROOK_S, V.BISHOP_S, V.QUEEN_S].includes(oppPiece)
 179           )
 180           ||
 181           (
 182             [V.BISHOP, V.BISHOP_S].includes(oppPiece) &&
 183             step.some(e => e == 0)
 184           )
 185           ||
 186           (
 187             [V.ROOK, V.ROOK_S].includes(oppPiece) &&
 188             step.every(e => e != 0)
 189           )
 190         ) {
 191           continue;
 192         }
 193         return true;
 194       }
 195     }
 196     return false;
 197   }
 198
 199   postPlay() {}
 200   postUndo() {}
 201
 202   getCheckSquares() {
 203     return [];
 204   }
 205   filterValid(moves) {
 206     return moves;
 207   }
 208
 209   getCurrentScore() {
 210     // Try both colors (to detect potential suicides)
 211     for (let c of ['w', 'b']) {
 212       const oppCol = V.GetOppCol(c);
 213       const goal = (c == 'w' ? 0 : 5);
 214       if (
 215         this.board[goal].some(
 216           (b,j) => b[0] == c && !this.findCaptures([goal, j])
 217         )
 218       ) {
 219         return c == 'w' ? "1-0" : "0-1";
 220       }
 221     }
 222     return super.getCurrentScore();
 223   }
 224
 225   static get VALUES() {
 226     return {
 227       r: 5,
 228       b: 3,
 229       q: 9,
 230       t: 3,
 231       c: 2,
 232       s: 5
 233     };
 234   }
 235
 236 };