1 import { ChessRules
} from "@/base_rules";
2 import { ArrayFun
} from "@/utils/array";
3 import { sample
, randInt
} from "@/utils/alea";
5 export const VariantRules
= class WildebeestRules
extends ChessRules
{
7 return { x: 10, y: 11 };
13 static get WILDEBEEST() {
18 return ChessRules
.PIECES
.concat([V
.CAMEL
, V
.WILDEBEEST
]);
23 ChessRules
.steps
, //add camel moves:
39 static IsGoodEnpassant(enpassant
) {
40 if (enpassant
!= "-") {
41 const squares
= enpassant
.split(",");
42 if (squares
.length
> 2) return false;
43 for (let sq
of squares
) {
44 const ep
= V
.SquareToCoords(sq
);
45 if (isNaN(ep
.x
) || !V
.OnBoard(ep
)) return false;
52 return ([V
.CAMEL
, V
.WILDEBEEST
].includes(b
[1]) ? "Wildebeest/" : "") + b
;
55 // There may be 2 enPassant squares (if pawn jump 3 squares)
57 const L
= this.epSquares
.length
;
58 if (!this.epSquares
[L
- 1]) return "-"; //no en-passant
60 this.epSquares
[L
- 1].forEach(sq
=> {
61 res
+= V
.CoordsToSquare(sq
) + ",";
63 return res
.slice(0, -1); //remove last comma
66 // En-passant after 2-sq or 3-sq jumps
67 getEpSquare(moveOrSquare
) {
68 if (!moveOrSquare
) return undefined;
69 if (typeof moveOrSquare
=== "string") {
70 const square
= moveOrSquare
;
71 if (square
== "-") return undefined;
73 square
.split(",").forEach(sq
=> {
74 res
.push(V
.SquareToCoords(sq
));
78 // Argument is a move:
79 const move = moveOrSquare
;
80 const [sx
, sy
, ex
] = [move.start
.x
, move.start
.y
, move.end
.x
];
81 if (this.getPiece(sx
, sy
) == V
.PAWN
&& Math
.abs(sx
- ex
) >= 2) {
82 const step
= (ex
- sx
) / Math
.abs(ex
- sx
);
89 if (sx
+ 2 * step
!= ex
) {
98 return undefined; //default
101 getPotentialMovesFrom([x
, y
]) {
102 switch (this.getPiece(x
, y
)) {
104 return this.getPotentialCamelMoves([x
, y
]);
106 return this.getPotentialWildebeestMoves([x
, y
]);
108 return super.getPotentialMovesFrom([x
, y
]);
112 // Pawns jump 2 or 3 squares, and promote to queen or wildebeest
113 getPotentialPawnMoves([x
, y
]) {
114 const color
= this.turn
;
116 const [sizeX
, sizeY
] = [V
.size
.x
, V
.size
.y
];
117 const shiftX
= color
== "w" ? -1 : 1;
118 const startRanks
= color
== "w" ? [sizeX
- 2, sizeX
- 3] : [1, 2];
119 const lastRank
= color
== "w" ? 0 : sizeX
- 1;
121 x
+ shiftX
== lastRank
? [V
.ROOK
, V
.KNIGHT
, V
.BISHOP
, V
.QUEEN
] : [V
.PAWN
];
123 if (this.board
[x
+ shiftX
][y
] == V
.EMPTY
) {
124 // One square forward
125 for (let piece
of finalPieces
)
127 this.getBasicMove([x
, y
], [x
+ shiftX
, y
], { c: color
, p: piece
})
129 if (startRanks
.includes(x
)) {
130 if (this.board
[x
+ 2 * shiftX
][y
] == V
.EMPTY
) {
132 moves
.push(this.getBasicMove([x
, y
], [x
+ 2 * shiftX
, y
]));
133 if (x
== startRanks
[0] && this.board
[x
+ 3 * shiftX
][y
] == V
.EMPTY
) {
134 // Three squares jump
135 moves
.push(this.getBasicMove([x
, y
], [x
+ 3 * shiftX
, y
]));
141 for (let shiftY
of [-1, 1]) {
144 y
+ shiftY
< sizeY
&&
145 this.board
[x
+ shiftX
][y
+ shiftY
] != V
.EMPTY
&&
146 this.canTake([x
, y
], [x
+ shiftX
, y
+ shiftY
])
148 for (let piece
of finalPieces
) {
150 this.getBasicMove([x
, y
], [x
+ shiftX
, y
+ shiftY
], {
160 const Lep
= this.epSquares
.length
;
161 const epSquare
= this.epSquares
[Lep
- 1];
163 for (let epsq
of epSquare
) {
164 // TODO: some redundant checks
165 if (epsq
.x
== x
+ shiftX
&& Math
.abs(epsq
.y
- y
) == 1) {
166 var enpassantMove
= this.getBasicMove([x
, y
], [epsq
.x
, epsq
.y
]);
167 // WARNING: the captured pawn may be diagonally behind us,
168 // if it's a 3-squares jump and we take on 1st passing square
169 const px
= this.board
[x
][epsq
.y
] != V
.EMPTY
? x : x
- shiftX
;
170 enpassantMove
.vanish
.push({
174 c: this.getColor(px
, epsq
.y
)
176 moves
.push(enpassantMove
);
184 // TODO: wildebeest castle
186 getPotentialCamelMoves(sq
) {
187 return this.getSlideNJumpMoves(sq
, V
.steps
[V
.CAMEL
], "oneStep");
190 getPotentialWildebeestMoves(sq
) {
191 return this.getSlideNJumpMoves(
193 V
.steps
[V
.KNIGHT
].concat(V
.steps
[V
.CAMEL
]),
198 isAttacked(sq
, colors
) {
200 super.isAttacked(sq
, colors
) ||
201 this.isAttackedByCamel(sq
, colors
) ||
202 this.isAttackedByWildebeest(sq
, colors
)
206 isAttackedByCamel(sq
, colors
) {
207 return this.isAttackedBySlideNJump(
216 isAttackedByWildebeest(sq
, colors
) {
217 return this.isAttackedBySlideNJump(
221 V
.steps
[V
.KNIGHT
].concat(V
.steps
[V
.CAMEL
]),
227 if (this.atLeastOneMove())
231 // No valid move: game is lost (stalemate is a win)
232 return this.turn
== "w" ? "0-1" : "1-0";
235 static get VALUES() {
236 return Object
.assign(
238 { c: 3, w: 7 } //experimental
242 static get SEARCH_DEPTH() {
246 static GenRandInitFen() {
247 let pieces
= { w: new Array(10), b: new Array(10) };
248 for (let c
of ["w", "b"]) {
249 let positions
= ArrayFun
.range(11);
251 // Get random squares for bishops + camels (different colors)
252 let randIndexes
= sample(ArrayFun
.range(6), 2).map(i
=> {
255 let bishop1Pos
= positions
[randIndexes
[0]];
256 let camel1Pos
= positions
[randIndexes
[1]];
257 // The second bishop (camel) must be on a square of different color
258 let randIndexes_tmp
= sample(ArrayFun
.range(5), 2).map(i
=> {
261 let bishop2Pos
= positions
[randIndexes_tmp
[0]];
262 let camel2Pos
= positions
[randIndexes_tmp
[1]];
263 for (let idx
of randIndexes
.concat(randIndexes_tmp
).sort((a
, b
) => {
266 //largest indices first
267 positions
.splice(idx
, 1);
270 let randIndex
= randInt(7);
271 let knight1Pos
= positions
[randIndex
];
272 positions
.splice(randIndex
, 1);
273 randIndex
= randInt(6);
274 let knight2Pos
= positions
[randIndex
];
275 positions
.splice(randIndex
, 1);
277 randIndex
= randInt(5);
278 let queenPos
= positions
[randIndex
];
279 positions
.splice(randIndex
, 1);
281 // Random square for wildebeest
282 randIndex
= randInt(4);
283 let wildebeestPos
= positions
[randIndex
];
284 positions
.splice(randIndex
, 1);
286 let rook1Pos
= positions
[0];
287 let kingPos
= positions
[1];
288 let rook2Pos
= positions
[2];
290 pieces
[c
][rook1Pos
] = "r";
291 pieces
[c
][knight1Pos
] = "n";
292 pieces
[c
][bishop1Pos
] = "b";
293 pieces
[c
][queenPos
] = "q";
294 pieces
[c
][camel1Pos
] = "c";
295 pieces
[c
][camel2Pos
] = "c";
296 pieces
[c
][wildebeestPos
] = "w";
297 pieces
[c
][kingPos
] = "k";
298 pieces
[c
][bishop2Pos
] = "b";
299 pieces
[c
][knight2Pos
] = "n";
300 pieces
[c
][rook2Pos
] = "r";
303 pieces
["b"].join("") +
304 "/ppppppppppp/11/11/11/11/11/11/PPPPPPPPPPP/" +
305 pieces
["w"].join("").toUpperCase() +