1 import { ArrayFun
} from "@/utils/array";
2 import { randInt
} from "@/utils/alea";
3 import { ChessRules
, PiPo
, Move
} from "@/base_rules";
5 export const VariantRules
= class EightpiecesRules
extends ChessRules
{
16 // Lancer directions *from white perspective*
17 static get LANCER_DIRS() {
31 return ChessRules
.PIECES
32 .concat([V
.JAILER
, V
.SENTRY
])
33 .concat(Object
.keys(V
.LANCER_DIRS
));
37 const piece
= this.board
[i
][j
].charAt(1);
38 // Special lancer case: 8 possible orientations
39 if (Object
.keys(V
.LANCER_DIRS
).includes(piece
)) return V
.LANCER
;
43 getPpath(b
, color
, score
, orientation
) {
44 if ([V
.JAILER
, V
.SENTRY
].includes(b
[1])) return "Eightpieces/" + b
;
45 if (Object
.keys(V
.LANCER_DIRS
).includes(b
[1])) {
46 if (orientation
== 'w') return "Eightpieces/" + b
;
47 // Find opposite direction for adequate display:
75 return "Eightpieces/" + b
[0] + oppDir
;
80 getPPpath(b
, orientation
) {
81 return this.getPpath(b
, null, null, orientation
);
84 static ParseFen(fen
) {
85 const fenParts
= fen
.split(" ");
87 ChessRules
.ParseFen(fen
),
88 { sentrypush: fenParts
[5] }
92 static IsGoodFen(fen
) {
93 if (!ChessRules
.IsGoodFen(fen
)) return false;
94 const fenParsed
= V
.ParseFen(fen
);
95 // 5) Check sentry push (if any)
97 fenParsed
.sentrypush
!= "-" &&
98 !fenParsed
.sentrypush
.match(/^([a-h][1-8],?)+$/)
106 return super.getFen() + " " + this.getSentrypushFen();
110 return super.getFenForRepeat() + "_" + this.getSentrypushFen();
114 const L
= this.sentryPush
.length
;
115 if (!this.sentryPush
[L
-1]) return "-";
117 this.sentryPush
[L
-1].forEach(coords
=>
118 res
+= V
.CoordsToSquare(coords
) + ",");
119 return res
.slice(0, -1);
122 setOtherVariables(fen
) {
123 super.setOtherVariables(fen
);
124 // subTurn == 2 only when a sentry moved, and is about to push something
126 // Sentry position just after a "capture" (subTurn from 1 to 2)
127 this.sentryPos
= null;
128 // Stack pieces' forbidden squares after a sentry move at each turn
129 const parsedFen
= V
.ParseFen(fen
);
130 if (parsedFen
.sentrypush
== "-") this.sentryPush
= [null];
133 parsedFen
.sentrypush
.split(",").map(sq
=> {
134 return V
.SquareToCoords(sq
);
140 static GenRandInitFen(randomness
) {
143 return "jsfqkbnr/pppppppp/8/8/8/8/PPPPPPPP/JSDQKBNR w 0 ahah - -";
145 let pieces
= { w: new Array(8), b: new Array(8) };
147 // Shuffle pieces on first (and last rank if randomness == 2)
148 for (let c
of ["w", "b"]) {
149 if (c
== 'b' && randomness
== 1) {
150 const lancerIdx
= pieces
['w'].findIndex(p
=> {
151 return Object
.keys(V
.LANCER_DIRS
).includes(p
);
154 pieces
['w'].slice(0, lancerIdx
)
156 .concat(pieces
['w'].slice(lancerIdx
+ 1));
161 let positions
= ArrayFun
.range(8);
163 // Get random squares for bishop and sentry
164 let randIndex
= 2 * randInt(4);
165 let bishopPos
= positions
[randIndex
];
166 // The sentry must be on a square of different color
167 let randIndex_tmp
= 2 * randInt(4) + 1;
168 let sentryPos
= positions
[randIndex_tmp
];
170 // Check if white sentry is on the same color as ours.
171 // If yes: swap bishop and sentry positions.
172 if ((pieces
['w'].indexOf('s') - sentryPos
) % 2 == 0)
173 [bishopPos
, sentryPos
] = [sentryPos
, bishopPos
];
175 positions
.splice(Math
.max(randIndex
, randIndex_tmp
), 1);
176 positions
.splice(Math
.min(randIndex
, randIndex_tmp
), 1);
178 // Get random squares for knight and lancer
179 randIndex
= randInt(6);
180 const knightPos
= positions
[randIndex
];
181 positions
.splice(randIndex
, 1);
182 randIndex
= randInt(5);
183 const lancerPos
= positions
[randIndex
];
184 positions
.splice(randIndex
, 1);
186 // Get random square for queen
187 randIndex
= randInt(4);
188 const queenPos
= positions
[randIndex
];
189 positions
.splice(randIndex
, 1);
191 // Rook, jailer and king positions are now almost fixed,
192 // only the ordering rook-> jailer or jailer->rook must be decided.
193 let rookPos
= positions
[0];
194 let jailerPos
= positions
[2];
195 const kingPos
= positions
[1];
196 flags
+= V
.CoordToColumn(rookPos
) + V
.CoordToColumn(jailerPos
);
197 if (Math
.random() < 0.5) [rookPos
, jailerPos
] = [jailerPos
, rookPos
];
199 pieces
[c
][rookPos
] = "r";
200 pieces
[c
][knightPos
] = "n";
201 pieces
[c
][bishopPos
] = "b";
202 pieces
[c
][queenPos
] = "q";
203 pieces
[c
][kingPos
] = "k";
204 pieces
[c
][sentryPos
] = "s";
205 // Lancer faces north for white, and south for black:
206 pieces
[c
][lancerPos
] = c
== 'w' ? 'c' : 'g';
207 pieces
[c
][jailerPos
] = "j";
210 pieces
["b"].join("") +
211 "/pppppppp/8/8/8/8/PPPPPPPP/" +
212 pieces
["w"].join("").toUpperCase() +
213 " w 0 " + flags
+ " - -"
217 canTake([x1
, y1
], [x2
, y2
]) {
218 if (this.subTurn
== 2)
219 // Only self captures on this subturn:
220 return this.getColor(x1
, y1
) == this.getColor(x2
, y2
);
221 return super.canTake([x1
, y1
], [x2
, y2
]);
224 // Is piece on square (x,y) immobilized?
225 isImmobilized([x
, y
]) {
226 const color
= this.getColor(x
, y
);
227 const oppCol
= V
.GetOppCol(color
);
228 for (let step
of V
.steps
[V
.ROOK
]) {
229 const [i
, j
] = [x
+ step
[0], y
+ step
[1]];
232 this.board
[i
][j
] != V
.EMPTY
&&
233 this.getColor(i
, j
) == oppCol
235 if (this.getPiece(i
, j
) == V
.JAILER
) return [i
, j
];
241 // Because of the lancers, getPiece() could be wrong:
242 // use board[x][y][1] instead (always valid).
243 getBasicMove([sx
, sy
], [ex
, ey
], tr
) {
249 c: tr
? tr
.c : this.getColor(sx
, sy
),
250 p: tr
? tr
.p : this.board
[sx
][sy
].charAt(1)
257 c: this.getColor(sx
, sy
),
258 p: this.board
[sx
][sy
].charAt(1)
263 // The opponent piece disappears if we take it
264 if (this.board
[ex
][ey
] != V
.EMPTY
) {
269 c: this.getColor(ex
, ey
),
270 p: this.board
[ex
][ey
].charAt(1)
278 canIplay(side
, [x
, y
]) {
280 (this.subTurn
== 1 && this.turn
== side
&& this.getColor(x
, y
) == side
) ||
281 (this.subTurn
== 2 && x
== this.sentryPos
.x
&& y
== this.sentryPos
.y
)
285 getPotentialMovesFrom([x
, y
]) {
286 // At subTurn == 2, jailers aren't effective (Jeff K)
287 if (this.subTurn
== 1) {
288 const jsq
= this.isImmobilized([x
, y
]);
291 // Special pass move if king:
292 if (this.getPiece(x
, y
) == V
.KING
) {
297 start: { x: x
, y: y
},
298 end: { x: jsq
[0], y: jsq
[1] }
306 switch (this.getPiece(x
, y
)) {
308 moves
= this.getPotentialJailerMoves([x
, y
]);
311 moves
= this.getPotentialSentryMoves([x
, y
]);
314 moves
= this.getPotentialLancerMoves([x
, y
]);
317 moves
= super.getPotentialMovesFrom([x
, y
]);
320 const L
= this.sentryPush
.length
;
321 if (!!this.sentryPush
[L
-1]) {
322 // Delete moves walking back on sentry push path
323 moves
= moves
.filter(m
=> {
325 m
.vanish
[0].p
!= V
.PAWN
&&
326 this.sentryPush
[L
-1].some(sq
=> sq
.x
== m
.end
.x
&& sq
.y
== m
.end
.y
)
332 } else if (this.subTurn
== 2) {
333 // Put back the sentinel on board:
334 const color
= this.turn
;
336 m
.appear
.push({x: x
, y: y
, p: V
.SENTRY
, c: color
});
342 getPotentialPawnMoves([x
, y
]) {
343 const color
= this.getColor(x
, y
);
345 const [sizeX
, sizeY
] = [V
.size
.x
, V
.size
.y
];
346 let shiftX
= (color
== "w" ? -1 : 1);
347 if (this.subTurn
== 2) shiftX
*= -1;
348 const firstRank
= color
== "w" ? sizeX
- 1 : 0;
349 const startRank
= color
== "w" ? sizeX
- 2 : 1;
350 const lastRank
= color
== "w" ? 0 : sizeX
- 1;
352 // Pawns might be pushed on 1st rank and attempt to move again:
353 if (!V
.OnBoard(x
+ shiftX
, y
)) return [];
356 // A push cannot put a pawn on last rank (it goes backward)
357 x
+ shiftX
== lastRank
358 ? Object
.keys(V
.LANCER_DIRS
).concat(
359 [V
.ROOK
, V
.KNIGHT
, V
.BISHOP
, V
.QUEEN
, V
.SENTRY
, V
.JAILER
])
361 if (this.board
[x
+ shiftX
][y
] == V
.EMPTY
) {
362 // One square forward
363 for (let piece
of finalPieces
) {
365 this.getBasicMove([x
, y
], [x
+ shiftX
, y
], {
372 // 2-squares jumps forbidden if pawn push
374 [startRank
, firstRank
].includes(x
) &&
375 this.board
[x
+ 2 * shiftX
][y
] == V
.EMPTY
378 moves
.push(this.getBasicMove([x
, y
], [x
+ 2 * shiftX
, y
]));
382 for (let shiftY
of [-1, 1]) {
385 y
+ shiftY
< sizeY
&&
386 this.board
[x
+ shiftX
][y
+ shiftY
] != V
.EMPTY
&&
387 this.canTake([x
, y
], [x
+ shiftX
, y
+ shiftY
])
389 for (let piece
of finalPieces
) {
391 this.getBasicMove([x
, y
], [x
+ shiftX
, y
+ shiftY
], {
400 // En passant: only on subTurn == 1
401 const Lep
= this.epSquares
.length
;
402 const epSquare
= this.epSquares
[Lep
- 1];
406 epSquare
.x
== x
+ shiftX
&&
407 Math
.abs(epSquare
.y
- y
) == 1
409 let enpassantMove
= this.getBasicMove([x
, y
], [epSquare
.x
, epSquare
.y
]);
410 enpassantMove
.vanish
.push({
414 c: this.getColor(x
, epSquare
.y
)
416 moves
.push(enpassantMove
);
422 // Obtain all lancer moves in "step" direction
423 getPotentialLancerMoves_aux([x
, y
], step
, tr
) {
425 // Add all moves to vacant squares until opponent is met:
426 const color
= this.getColor(x
, y
);
430 // at subTurn == 2, consider own pieces as opponent
432 let sq
= [x
+ step
[0], y
+ step
[1]];
433 while (V
.OnBoard(sq
[0], sq
[1]) && this.getColor(sq
[0], sq
[1]) != oppCol
) {
434 if (this.board
[sq
[0]][sq
[1]] == V
.EMPTY
)
435 moves
.push(this.getBasicMove([x
, y
], sq
, tr
));
439 if (V
.OnBoard(sq
[0], sq
[1]))
440 // Add capturing move
441 moves
.push(this.getBasicMove([x
, y
], sq
, tr
));
445 getPotentialLancerMoves([x
, y
]) {
447 // Add all lancer possible orientations, similar to pawn promotions.
448 // Except if just after a push: allow all movements from init square then
449 const L
= this.sentryPush
.length
;
450 const color
= this.getColor(x
, y
);
451 if (!!this.sentryPush
[L
-1]) {
452 // Maybe I was pushed
453 const pl
= this.sentryPush
[L
-1].length
;
455 this.sentryPush
[L
-1][pl
-1].x
== x
&&
456 this.sentryPush
[L
-1][pl
-1].y
== y
458 // I was pushed: allow all directions (for this move only), but
459 // do not change direction after moving, *except* if I keep the
460 // same orientation in which I was pushed.
461 const curDir
= V
.LANCER_DIRS
[this.board
[x
][y
].charAt(1)];
462 Object
.values(V
.LANCER_DIRS
).forEach(step
=> {
463 const dirCode
= Object
.keys(V
.LANCER_DIRS
).find(k
=> {
465 V
.LANCER_DIRS
[k
][0] == step
[0] &&
466 V
.LANCER_DIRS
[k
][1] == step
[1]
470 this.getPotentialLancerMoves_aux(
473 { p: dirCode
, c: color
}
475 if (curDir
[0] == step
[0] && curDir
[1] == step
[1]) {
476 // Keeping same orientation: can choose after
477 let chooseMoves
= [];
478 dirMoves
.forEach(m
=> {
479 Object
.keys(V
.LANCER_DIRS
).forEach(k
=> {
480 let mk
= JSON
.parse(JSON
.stringify(m
));
485 Array
.prototype.push
.apply(moves
, chooseMoves
);
486 } else Array
.prototype.push
.apply(moves
, dirMoves
);
491 // I wasn't pushed: standard lancer move
492 const dirCode
= this.board
[x
][y
][1];
494 this.getPotentialLancerMoves_aux([x
, y
], V
.LANCER_DIRS
[dirCode
]);
495 // Add all possible orientations aftermove except if I'm being pushed
496 if (this.subTurn
== 1) {
497 monodirMoves
.forEach(m
=> {
498 Object
.keys(V
.LANCER_DIRS
).forEach(k
=> {
499 let mk
= JSON
.parse(JSON
.stringify(m
));
506 // I'm pushed: add potential nudges
507 let potentialNudges
= [];
508 for (let step
of V
.steps
[V
.ROOK
].concat(V
.steps
[V
.BISHOP
])) {
510 V
.OnBoard(x
+ step
[0], y
+ step
[1]) &&
511 this.board
[x
+ step
[0]][y
+ step
[1]] == V
.EMPTY
513 const newDirCode
= Object
.keys(V
.LANCER_DIRS
).find(k
=> {
514 const codeStep
= V
.LANCER_DIRS
[k
];
515 return (codeStep
[0] == step
[0] && codeStep
[1] == step
[1]);
517 potentialNudges
.push(
520 [x
+ step
[0], y
+ step
[1]],
521 { c: color
, p: newDirCode
}
526 return monodirMoves
.concat(potentialNudges
);
530 getPotentialSentryMoves([x
, y
]) {
531 // The sentry moves a priori like a bishop:
532 let moves
= super.getPotentialBishopMoves([x
, y
]);
533 // ...but captures are replaced by special move, if and only if
534 // "captured" piece can move now, considered as the capturer unit.
535 // --> except is subTurn == 2, in this case I don't push anything.
536 if (this.subTurn
== 2) return moves
.filter(m
=> m
.vanish
.length
== 1);
538 if (m
.vanish
.length
== 2) {
539 // Temporarily cancel the sentry capture:
544 const color
= this.getColor(x
, y
);
545 const fMoves
= moves
.filter(m
=> {
546 // Can the pushed unit make any move? ...resulting in a non-self-check?
547 if (m
.appear
.length
== 0) {
550 let moves2
= this.getPotentialMovesFrom([m
.end
.x
, m
.end
.y
]);
551 for (let m2
of moves2
) {
553 res
= !this.underCheck(color
);
565 getPotentialJailerMoves([x
, y
]) {
566 return super.getPotentialRookMoves([x
, y
]).filter(m
=> {
567 // Remove jailer captures
568 return m
.vanish
[0].p
!= V
.JAILER
|| m
.vanish
.length
== 1;
572 getPotentialKingMoves(sq
) {
573 const moves
= this.getSlideNJumpMoves(
575 V
.steps
[V
.ROOK
].concat(V
.steps
[V
.BISHOP
]),
580 ? moves
.concat(this.getCastleMoves(sq
))
585 // Adapted: castle with jailer possible
586 getCastleMoves([x
, y
]) {
587 const c
= this.getColor(x
, y
);
588 const firstRank
= (c
== "w" ? V
.size
.x
- 1 : 0);
589 if (x
!= firstRank
|| y
!= this.INIT_COL_KING
[c
])
592 const oppCol
= V
.GetOppCol(c
);
595 // King, then rook or jailer:
596 const finalSquares
= [
598 [V
.size
.y
- 2, V
.size
.y
- 3]
605 if (this.castleFlags
[c
][castleSide
] >= 8) continue;
606 // Rook (or jailer) and king are on initial position
607 const finDist
= finalSquares
[castleSide
][0] - y
;
608 let step
= finDist
/ Math
.max(1, Math
.abs(finDist
));
612 this.isAttacked([x
, i
], [oppCol
]) ||
613 (this.board
[x
][i
] != V
.EMPTY
&&
614 (this.getColor(x
, i
) != c
||
615 ![V
.KING
, V
.ROOK
, V
.JAILER
].includes(this.getPiece(x
, i
))))
617 continue castlingCheck
;
620 } while (i
!= finalSquares
[castleSide
][0]);
621 step
= castleSide
== 0 ? -1 : 1;
622 const rookOrJailerPos
= this.castleFlags
[c
][castleSide
];
623 for (i
= y
+ step
; i
!= rookOrJailerPos
; i
+= step
)
624 if (this.board
[x
][i
] != V
.EMPTY
) continue castlingCheck
;
626 // Nothing on final squares, except maybe king and castling rook or jailer?
627 for (i
= 0; i
< 2; i
++) {
629 this.board
[x
][finalSquares
[castleSide
][i
]] != V
.EMPTY
&&
630 this.getPiece(x
, finalSquares
[castleSide
][i
]) != V
.KING
&&
631 finalSquares
[castleSide
][i
] != rookOrJailerPos
633 continue castlingCheck
;
637 // If this code is reached, castle is valid
638 const castlingPiece
= this.getPiece(firstRank
, rookOrJailerPos
);
642 new PiPo({ x: x
, y: finalSquares
[castleSide
][0], p: V
.KING
, c: c
}),
643 new PiPo({ x: x
, y: finalSquares
[castleSide
][1], p: castlingPiece
, c: c
})
646 new PiPo({ x: x
, y: y
, p: V
.KING
, c: c
}),
647 new PiPo({ x: x
, y: rookOrJailerPos
, p: castlingPiece
, c: c
})
650 Math
.abs(y
- rookOrJailerPos
) <= 2
651 ? { x: x
, y: rookOrJailerPos
}
652 : { x: x
, y: y
+ 2 * (castleSide
== 0 ? -1 : 1) }
661 // If in second-half of a move, we already know that a move is possible
662 if (this.subTurn
== 2) return true;
663 return super.atLeastOneMove();
667 if (moves
.length
== 0) return [];
668 const basicFilter
= (m
, c
) => {
670 const res
= !this.underCheck(c
);
674 // Disable check tests for sentry pushes,
675 // because in this case the move isn't finished
676 let movesWithoutSentryPushes
= [];
677 let movesWithSentryPushes
= [];
679 // Second condition below for special king "pass" moves
680 if (m
.appear
.length
> 0 || m
.vanish
.length
== 0)
681 movesWithoutSentryPushes
.push(m
);
682 else movesWithSentryPushes
.push(m
);
684 const color
= this.turn
;
685 const oppCol
= V
.GetOppCol(color
);
686 const filteredMoves
=
687 movesWithoutSentryPushes
.filter(m
=> basicFilter(m
, color
));
688 // If at least one full move made, everything is allowed.
689 // Else: forbid checks and captures.
693 : filteredMoves
.filter(m
=> {
694 return (m
.vanish
.length
<= 1 && basicFilter(m
, oppCol
));
696 ).concat(movesWithSentryPushes
);
700 if (this.subTurn
== 1) return super.getAllValidMoves();
702 const sentrySq
= [this.sentryPos
.x
, this.sentryPos
.y
];
703 return this.filterValid(this.getPotentialMovesFrom(sentrySq
));
707 if (move.appear
.length
== 0 && move.vanish
.length
== 1)
708 // The sentry is about to push a piece: subTurn goes from 1 to 2
709 this.sentryPos
= { x: move.end
.x
, y: move.end
.y
};
710 if (this.subTurn
== 2 && move.vanish
[0].p
!= V
.PAWN
) {
711 // A piece is pushed: forbid array of squares between start and end
712 // of move, included (except if it's a pawn)
714 if ([V
.KNIGHT
,V
.KING
].includes(move.vanish
[0].p
))
715 // short-range pieces: just forbid initial square
716 squares
.push({ x: move.start
.x
, y: move.start
.y
});
718 const deltaX
= move.end
.x
- move.start
.x
;
719 const deltaY
= move.end
.y
- move.start
.y
;
721 deltaX
/ Math
.abs(deltaX
) || 0,
722 deltaY
/ Math
.abs(deltaY
) || 0
725 let sq
= {x: move.start
.x
, y: move.start
.y
};
726 sq
.x
!= move.end
.x
|| sq
.y
!= move.end
.y
;
727 sq
.x
+= step
[0], sq
.y
+= step
[1]
729 squares
.push({ x: sq
.x
, y: sq
.y
});
732 // Add end square as well, to know if I was pushed (useful for lancers)
733 squares
.push({ x: move.end
.x
, y: move.end
.y
});
734 this.sentryPush
.push(squares
);
735 } else this.sentryPush
.push(null);
739 // if (!this.states) this.states = [];
740 // const stateFen = this.getFen();
741 // this.states.push(stateFen);
744 move.flags
= JSON
.stringify(this.aggregateFlags());
745 this.epSquares
.push(this.getEpSquare(move));
746 V
.PlayOnBoard(this.board
, move);
747 // Is it a sentry push? (useful for undo)
748 move.sentryPush
= (this.subTurn
== 2);
749 if (this.subTurn
== 1) this.movesCount
++;
750 if (move.appear
.length
== 0 && move.vanish
.length
== 1) this.subTurn
= 2;
752 // Turn changes only if not a sentry "pre-push"
753 this.turn
= V
.GetOppCol(this.turn
);
760 if (move.vanish
.length
== 0 || this.subTurn
== 2)
761 // Special pass move of the king, or sentry pre-push: nothing to update
763 const c
= move.vanish
[0].c
;
764 const piece
= move.vanish
[0].p
;
765 const firstRank
= c
== "w" ? V
.size
.x
- 1 : 0;
767 if (piece
== V
.KING
) {
768 this.kingPos
[c
][0] = move.appear
[0].x
;
769 this.kingPos
[c
][1] = move.appear
[0].y
;
770 this.castleFlags
[c
] = [V
.size
.y
, V
.size
.y
];
773 // Update castling flags if rooks are moved
774 const oppCol
= V
.GetOppCol(c
);
775 const oppFirstRank
= V
.size
.x
- 1 - firstRank
;
777 move.start
.x
== firstRank
&& //our rook moves?
778 this.castleFlags
[c
].includes(move.start
.y
)
780 const flagIdx
= (move.start
.y
== this.castleFlags
[c
][0] ? 0 : 1);
781 this.castleFlags
[c
][flagIdx
] = V
.size
.y
;
783 move.end
.x
== oppFirstRank
&& //we took opponent rook?
784 this.castleFlags
[oppCol
].includes(move.end
.y
)
786 const flagIdx
= (move.end
.y
== this.castleFlags
[oppCol
][0] ? 0 : 1);
787 this.castleFlags
[oppCol
][flagIdx
] = V
.size
.y
;
792 this.epSquares
.pop();
793 this.disaggregateFlags(JSON
.parse(move.flags
));
794 V
.UndoOnBoard(this.board
, move);
795 // Decrement movesCount except if the move is a sentry push
796 if (!move.sentryPush
) this.movesCount
--;
797 if (this.subTurn
== 2) this.subTurn
= 1;
799 this.turn
= V
.GetOppCol(this.turn
);
800 if (move.sentryPush
) this.subTurn
= 2;
804 // const stateFen = this.getFen();
805 // if (stateFen != this.states[this.states.length-1]) debugger;
806 // this.states.pop();
810 super.postUndo(move);
811 this.sentryPush
.pop();
814 isAttacked(sq
, colors
) {
816 super.isAttacked(sq
, colors
) ||
817 this.isAttackedByLancer(sq
, colors
) ||
818 this.isAttackedBySentry(sq
, colors
)
822 isAttackedBySlideNJump([x
, y
], colors
, piece
, steps
, oneStep
) {
823 for (let step
of steps
) {
824 let rx
= x
+ step
[0],
826 while (V
.OnBoard(rx
, ry
) && this.board
[rx
][ry
] == V
.EMPTY
&& !oneStep
) {
832 this.getPiece(rx
, ry
) === piece
&&
833 colors
.includes(this.getColor(rx
, ry
)) &&
834 !this.isImmobilized([rx
, ry
])
842 isAttackedByPawn([x
, y
], colors
) {
843 for (let c
of colors
) {
844 const pawnShift
= c
== "w" ? 1 : -1;
845 if (x
+ pawnShift
>= 0 && x
+ pawnShift
< V
.size
.x
) {
846 for (let i
of [-1, 1]) {
850 this.getPiece(x
+ pawnShift
, y
+ i
) == V
.PAWN
&&
851 this.getColor(x
+ pawnShift
, y
+ i
) == c
&&
852 !this.isImmobilized([x
+ pawnShift
, y
+ i
])
862 isAttackedByLancer([x
, y
], colors
) {
863 for (let step
of V
.steps
[V
.ROOK
].concat(V
.steps
[V
.BISHOP
])) {
864 // If in this direction there are only enemy pieces and empty squares,
865 // and we meet a lancer: can he reach us?
866 // NOTE: do not stop at first lancer, there might be several!
867 let coord
= { x: x
+ step
[0], y: y
+ step
[1] };
870 V
.OnBoard(coord
.x
, coord
.y
) &&
872 this.board
[coord
.x
][coord
.y
] == V
.EMPTY
||
873 colors
.includes(this.getColor(coord
.x
, coord
.y
))
877 this.getPiece(coord
.x
, coord
.y
) == V
.LANCER
&&
878 !this.isImmobilized([coord
.x
, coord
.y
])
880 lancerPos
.push({x: coord
.x
, y: coord
.y
});
885 for (let xy
of lancerPos
) {
886 const dir
= V
.LANCER_DIRS
[this.board
[xy
.x
][xy
.y
].charAt(1)];
887 if (dir
[0] == -step
[0] && dir
[1] == -step
[1]) return true;
893 // Helper to check sentries attacks:
894 selfAttack([x1
, y1
], [x2
, y2
]) {
895 const color
= this.getColor(x1
, y1
);
896 const sliderAttack
= (allowedSteps
, lancer
) => {
897 const deltaX
= x2
- x1
,
898 absDeltaX
= Math
.abs(deltaX
);
899 const deltaY
= y2
- y1
,
900 absDeltaY
= Math
.abs(deltaY
);
901 const step
= [ deltaX
/ absDeltaX
, deltaY
/ absDeltaY
];
903 // Check that the step is a priori valid:
904 (absDeltaX
!= absDeltaY
&& deltaX
!= 0 && deltaY
!= 0) ||
905 allowedSteps
.every(st
=> st
[0] != step
[0] || st
[1] != step
[1])
909 let sq
= [ x1
+ step
[0], y1
+ step
[1] ];
910 while (sq
[0] != x2
&& sq
[1] != y2
) {
912 // NOTE: no need to check OnBoard in this special case
913 (!lancer
&& this.board
[sq
[0]][sq
[1]] != V
.EMPTY
) ||
914 (!!lancer
&& this.getColor(sq
[0], sq
[1]) != color
)
923 switch (this.getPiece(x1
, y1
)) {
925 // Pushed pawns move as enemy pawns
926 const shift
= (color
== 'w' ? 1 : -1);
927 return (x1
+ shift
== x2
&& Math
.abs(y1
- y2
) == 1);
930 const deltaX
= Math
.abs(x1
- x2
);
931 const deltaY
= Math
.abs(y1
- y2
);
933 deltaX
+ deltaY
== 3 &&
934 [1, 2].includes(deltaX
) &&
935 [1, 2].includes(deltaY
)
939 return sliderAttack(V
.steps
[V
.ROOK
]);
941 return sliderAttack(V
.steps
[V
.BISHOP
]);
943 return sliderAttack(V
.steps
[V
.ROOK
].concat(V
.steps
[V
.BISHOP
]));
945 // Special case: as long as no enemy units stands in-between, it attacks
946 // (if it points toward the king).
947 const allowedStep
= V
.LANCER_DIRS
[this.board
[x1
][y1
].charAt(1)];
948 return sliderAttack([allowedStep
], "lancer");
950 // No sentries or jailer tests: they cannot self-capture
955 isAttackedBySentry([x
, y
], colors
) {
956 // Attacked by sentry means it can self-take our king.
957 // Just check diagonals of enemy sentry(ies), and if it reaches
958 // one of our pieces: can I self-take?
959 const color
= V
.GetOppCol(colors
[0]);
961 for (let i
=0; i
<V
.size
.x
; i
++) {
962 for (let j
=0; j
<V
.size
.y
; j
++) {
964 this.getPiece(i
,j
) == V
.SENTRY
&&
965 colors
.includes(this.getColor(i
,j
)) &&
966 !this.isImmobilized([i
, j
])
968 for (let step
of V
.steps
[V
.BISHOP
]) {
969 let sq
= [ i
+ step
[0], j
+ step
[1] ];
971 V
.OnBoard(sq
[0], sq
[1]) &&
972 this.board
[sq
[0]][sq
[1]] == V
.EMPTY
978 V
.OnBoard(sq
[0], sq
[1]) &&
979 this.getColor(sq
[0], sq
[1]) == color
981 candidates
.push([ sq
[0], sq
[1] ]);
987 for (let c
of candidates
)
988 if (this.selfAttack(c
, [x
, y
])) return true;
992 // Jailer doesn't capture or give check
994 static get VALUES() {
995 return Object
.assign(
996 { l: 4.8, s: 2.8, j: 3.8 }, //Jeff K. estimations
1002 const maxeval
= V
.INFINITY
;
1003 const color
= this.turn
;
1004 let moves1
= this.getAllValidMoves();
1006 if (moves1
.length
== 0)
1007 // TODO: this situation should not happen
1010 const setEval
= (move, next
) => {
1011 const score
= this.getCurrentScore();
1012 const curEval
= move.eval
;
1017 : (score
== "1-0" ? 1 : -1) * maxeval
;
1018 } else move.eval
= this.evalPosition();
1020 // "next" is defined after sentry pushes
1023 color
== 'w' && move.eval
> curEval
||
1024 color
== 'b' && move.eval
< curEval
1031 // Just search_depth == 1 (because of sentries. TODO: can do better...)
1032 moves1
.forEach(m1
=> {
1034 if (this.subTurn
== 1) setEval(m1
);
1036 // Need to play every pushes and count:
1037 const moves2
= this.getAllValidMoves();
1038 moves2
.forEach(m2
=> {
1047 moves1
.sort((a
, b
) => {
1048 return (color
== "w" ? 1 : -1) * (b
.eval
- a
.eval
);
1050 let candidates
= [0];
1051 for (let j
= 1; j
< moves1
.length
&& moves1
[j
].eval
== moves1
[0].eval
; j
++)
1053 const choice
= moves1
[candidates
[randInt(candidates
.length
)]];
1054 return (!choice
.second
? choice : [choice
, choice
.second
]);
1058 // Special case "king takes jailer" is a pass move
1059 if (move.appear
.length
== 0 && move.vanish
.length
== 0) return "pass";
1060 if (this.subTurn
== 2) {
1061 // Do not consider appear[1] (sentry) for sentry pushes
1062 const simpleMove
= {
1063 appear: [move.appear
[0]],
1064 vanish: move.vanish
,
1068 return super.getNotation(simpleMove
);
1070 return super.getNotation(move);