Start thinking about Coregal
[xogo.git] / base_rules.js
1 import {Random} from "/utils/alea.js";
2 import {ArrayFun} from "/utils/array.js";
3 import {FenUtil} from "/utils/setupPieces.js";
4 import PiPo from "/utils/PiPo.js";
5 import Move from "/utils/Move.js";
6
7 // Helper class for move animation
8 class TargetObj {
9
10 constructor(callOnComplete) {
11 this.value = 0;
12 this.target = 0;
13 this.callOnComplete = callOnComplete;
14 }
15 increment() {
16 if (++this.value == this.target)
17 this.callOnComplete();
18 }
19
20 };
21
22 // NOTE: x coords: top to bottom (white perspective); y: left to right
23 // NOTE: ChessRules is aliased as window.C, and variants as window.V
24 export default class ChessRules {
25
26 static get Aliases() {
27 return {'C': ChessRules};
28 }
29
30 /////////////////////////
31 // VARIANT SPECIFICATIONS
32
33 // Some variants have specific options, like the number of pawns in Monster,
34 // or the board size for Pandemonium.
35 // Users can generally select a randomness level from 0 to 2.
36 static get Options() {
37 return {
38 select: [{
39 label: "Randomness",
40 variable: "randomness",
41 defaut: 0,
42 options: [
43 {label: "Deterministic", value: 0},
44 {label: "Symmetric random", value: 1},
45 {label: "Asymmetric random", value: 2}
46 ]
47 }],
48 input: [
49 {
50 label: "Capture king",
51 variable: "taking",
52 type: "checkbox",
53 defaut: false
54 },
55 {
56 label: "Falling pawn",
57 variable: "pawnfall",
58 type: "checkbox",
59 defaut: false
60 }
61 ],
62 // Game modifiers (using "elementary variants"). Default: false
63 styles: [
64 "atomic",
65 "balance", //takes precedence over doublemove & progressive
66 "cannibal",
67 "capture",
68 "crazyhouse",
69 "cylinder", //ok with all
70 "dark",
71 "doublemove",
72 "madrasi",
73 "progressive", //(natural) priority over doublemove
74 "recycle",
75 "rifle",
76 "teleport",
77 "zen"
78 ]
79 };
80 }
81
82 get pawnPromotions() {
83 return ['q', 'r', 'n', 'b'];
84 }
85
86 // Some variants don't have flags:
87 get hasFlags() {
88 return true;
89 }
90 // Or castle
91 get hasCastle() {
92 return this.hasFlags;
93 }
94
95 // En-passant captures allowed?
96 get hasEnpassant() {
97 return true;
98 }
99
100 // Allow to take (moving: not disappearing) own pieces?
101 get hasSelfCaptures() {
102 return (
103 this.options["recycle"] ||
104 (this.options["teleport"] && this.subTurnTeleport == 1)
105 );
106 }
107
108 get hasReserve() {
109 return (
110 !!this.options["crazyhouse"] ||
111 (!!this.options["recycle"] && !this.options["teleport"])
112 );
113 }
114 // Some variants do not store reserve state (Align4, Chakart...)
115 get hasReserveFen() {
116 return this.hasReserve;
117 }
118
119 get noAnimate() {
120 return !!this.options["dark"];
121 }
122
123 // Some variants use only click information
124 get clickOnly() {
125 return false;
126 }
127
128 // Some variants reveal moves only after both players played
129 get hideMoves() {
130 return false;
131 }
132
133 // Some variants do not flip board as black
134 get flippedBoard() {
135 return (this.playerColor == 'b');
136 }
137
138 // Some variants use click infos:
139 doClick(coords) {
140 if (typeof coords.x != "number")
141 return null; //click on reserves
142 if (
143 this.options["teleport"] && this.subTurnTeleport == 2 &&
144 this.board[coords.x][coords.y] == ""
145 ) {
146 let res = new Move({
147 start: {x: this.captured.x, y: this.captured.y},
148 appear: [
149 new PiPo({
150 x: coords.x,
151 y: coords.y,
152 c: this.captured.c,
153 p: this.captured.p
154 })
155 ],
156 vanish: []
157 });
158 res.drag = {c: this.captured.c, p: this.captured.p};
159 return res;
160 }
161 return null;
162 }
163
164 ////////////////////
165 // COORDINATES UTILS
166
167 // 3a --> {x:3, y:10}
168 static SquareToCoords(sq) {
169 return ArrayFun.toObject(["x", "y"],
170 [0, 1].map(i => parseInt(sq[i], 36)));
171 }
172
173 // {x:11, y:12} --> bc
174 static CoordsToSquare(cd) {
175 return Object.values(cd).map(c => c.toString(36)).join("");
176 }
177
178 coordsToId(cd) {
179 if (typeof cd.x == "number") {
180 return (
181 `${this.containerId}|sq-${cd.x.toString(36)}-${cd.y.toString(36)}`
182 );
183 }
184 // Reserve :
185 return `${this.containerId}|rsq-${cd.x}-${cd.y}`;
186 }
187
188 idToCoords(targetId) {
189 if (!targetId)
190 return null; //outside page, maybe...
191 const idParts = targetId.split('|'); //prefix|sq-2-3 (start at 0 => 3,4)
192 if (
193 idParts.length < 2 ||
194 idParts[0] != this.containerId ||
195 !idParts[1].match(/sq-[0-9a-zA-Z]-[0-9a-zA-Z]/)
196 ) {
197 return null;
198 }
199 const squares = idParts[1].split('-');
200 if (squares[0] == "sq")
201 return {x: parseInt(squares[1], 36), y: parseInt(squares[2], 36)};
202 // squares[0] == "rsq" : reserve, 'c' + 'p' (letters color & piece)
203 return {x: squares[1], y: squares[2]};
204 }
205
206 /////////////
207 // FEN UTILS
208
209 // Turn "wb" into "B" (for FEN)
210 board2fen(b) {
211 return (b[0] == "w" ? b[1].toUpperCase() : b[1]);
212 }
213
214 // Turn "p" into "bp" (for board)
215 fen2board(f) {
216 return (f.charCodeAt(0) <= 90 ? "w" + f.toLowerCase() : "b" + f);
217 }
218
219 genRandInitFen(seed) {
220 Random.setSeed(seed); //may be unused
221 let baseFen = this.genRandInitBaseFen();
222 baseFen.o = Object.assign({init: true}, baseFen.o);
223 const parts = this.getPartFen(baseFen.o);
224 return (
225 baseFen.fen + " w 0" +
226 (Object.keys(parts).length > 0 ? (" " + JSON.stringify(parts)) : "")
227 );
228 }
229
230 // Setup the initial random-or-not (asymmetric-or-not) position
231 genRandInitBaseFen() {
232 const s = FenUtil.setupPieces(
233 ['r', 'n', 'b', 'q', 'k', 'b', 'n', 'r'],
234 {
235 randomness: this.options["randomness"],
236 between: [{p1: 'k', p2: 'r'}],
237 diffCol: ['b'],
238 flags: ['r']
239 }
240 );
241 return {
242 fen: s.b.join("") + "/pppppppp/8/8/8/8/PPPPPPPP/" +
243 s.w.join("").toUpperCase(),
244 o: {flags: s.flags}
245 };
246 }
247
248 // "Parse" FEN: just return untransformed string data
249 parseFen(fen) {
250 const fenParts = fen.split(" ");
251 let res = {
252 position: fenParts[0],
253 turn: fenParts[1],
254 movesCount: fenParts[2]
255 };
256 if (fenParts.length > 3)
257 res = Object.assign(res, JSON.parse(fenParts[3]));
258 return res;
259 }
260
261 // Return current fen (game state)
262 getFen() {
263 const parts = this.getPartFen({});
264 return (
265 this.getBaseFen() +
266 (Object.keys(parts).length > 0 ? (" " + JSON.stringify(parts)) : "")
267 );
268 }
269
270 getBaseFen() {
271 return this.getPosition() + " " + this.turn + " " + this.movesCount;
272 }
273
274 getPartFen(o) {
275 let parts = {};
276 if (this.hasFlags)
277 parts["flags"] = o.init ? o.flags : this.getFlagsFen();
278 if (this.hasEnpassant)
279 parts["enpassant"] = o.init ? "-" : this.getEnpassantFen();
280 if (this.hasReserveFen)
281 parts["reserve"] = this.getReserveFen(o);
282 if (this.options["crazyhouse"])
283 parts["ispawn"] = this.getIspawnFen(o);
284 return parts;
285 }
286
287 static FenEmptySquares(count) {
288 // if more than 9 consecutive free spaces, break the integer,
289 // otherwise FEN parsing will fail.
290 if (count <= 9)
291 return count;
292 // Most boards of size < 18:
293 if (count <= 18)
294 return "9" + (count - 9);
295 // Except Gomoku:
296 return "99" + (count - 18);
297 }
298
299 // Position part of the FEN string
300 getPosition() {
301 let position = "";
302 for (let i = 0; i < this.size.x; i++) {
303 let emptyCount = 0;
304 for (let j = 0; j < this.size.y; j++) {
305 if (this.board[i][j] == "")
306 emptyCount++;
307 else {
308 if (emptyCount > 0) {
309 // Add empty squares in-between
310 position += C.FenEmptySquares(emptyCount);
311 emptyCount = 0;
312 }
313 position += this.board2fen(this.board[i][j]);
314 }
315 }
316 if (emptyCount > 0)
317 // "Flush remainder"
318 position += C.FenEmptySquares(emptyCount);
319 if (i < this.size.x - 1)
320 position += "/"; //separate rows
321 }
322 return position;
323 }
324
325 // Flags part of the FEN string
326 getFlagsFen() {
327 return ["w", "b"].map(c => {
328 return this.castleFlags[c].map(x => x.toString(36)).join("");
329 }).join("");
330 }
331
332 // Enpassant part of the FEN string
333 getEnpassantFen() {
334 if (!this.epSquare)
335 return "-";
336 return C.CoordsToSquare(this.epSquare);
337 }
338
339 getReserveFen(o) {
340 if (o.init)
341 return "000000000000";
342 return (
343 ["w","b"].map(c => Object.values(this.reserve[c]).join("")).join("")
344 );
345 }
346
347 getIspawnFen(o) {
348 if (o.init)
349 // NOTE: cannot merge because this.ispawn doesn't exist yet
350 return "-";
351 const squares = Object.keys(this.ispawn);
352 if (squares.length == 0)
353 return "-";
354 return squares.join(",");
355 }
356
357 // Set flags from fen (castle: white a,h then black a,h)
358 setFlags(fenflags) {
359 this.castleFlags = {
360 w: [0, 1].map(i => parseInt(fenflags.charAt(i), 36)),
361 b: [2, 3].map(i => parseInt(fenflags.charAt(i), 36))
362 };
363 }
364
365 //////////////////
366 // INITIALIZATION
367
368 constructor(o) {
369 this.options = o.options;
370 // Fill missing options (always the case if random challenge)
371 (V.Options.select || []).concat(V.Options.input || []).forEach(opt => {
372 if (this.options[opt.variable] === undefined)
373 this.options[opt.variable] = opt.defaut;
374 });
375
376 // Some variables
377 this.playerColor = o.color;
378 this.afterPlay = o.afterPlay; //trigger some actions after playing a move
379 this.containerId = o.element;
380 this.isDiagram = o.diagram;
381 this.marks = o.marks;
382
383 // Initializations
384 if (!o.fen)
385 o.fen = this.genRandInitFen(o.seed);
386 this.re_initFromFen(o.fen);
387 this.graphicalInit();
388 }
389
390 re_initFromFen(fen, oldBoard) {
391 const fenParsed = this.parseFen(fen);
392 this.board = oldBoard || this.getBoard(fenParsed.position);
393 this.turn = fenParsed.turn;
394 this.movesCount = parseInt(fenParsed.movesCount, 10);
395 this.setOtherVariables(fenParsed);
396 }
397
398 // Turn position fen into double array ["wb","wp","bk",...]
399 getBoard(position) {
400 const rows = position.split("/");
401 let board = ArrayFun.init(this.size.x, this.size.y, "");
402 for (let i = 0; i < rows.length; i++) {
403 let j = 0;
404 for (let indexInRow = 0; indexInRow < rows[i].length; indexInRow++) {
405 const character = rows[i][indexInRow];
406 const num = parseInt(character, 10);
407 // If num is a number, just shift j:
408 if (!isNaN(num))
409 j += num;
410 // Else: something at position i,j
411 else
412 board[i][j++] = this.fen2board(character);
413 }
414 }
415 return board;
416 }
417
418 // Some additional variables from FEN (variant dependant)
419 setOtherVariables(fenParsed, pieceArray) {
420 // Set flags and enpassant:
421 if (this.hasFlags)
422 this.setFlags(fenParsed.flags);
423 if (this.hasEnpassant)
424 this.epSquare = this.getEpSquare(fenParsed.enpassant);
425 if (this.hasReserve && !this.isDiagram)
426 this.initReserves(fenParsed.reserve, pieceArray);
427 if (this.options["crazyhouse"])
428 this.initIspawn(fenParsed.ispawn);
429 if (this.options["teleport"]) {
430 this.subTurnTeleport = 1;
431 this.captured = null;
432 }
433 if (this.options["dark"]) {
434 // Setup enlightened: squares reachable by player side
435 this.enlightened = ArrayFun.init(this.size.x, this.size.y, false);
436 this.updateEnlightened();
437 }
438 this.subTurn = 1; //may be unused
439 if (!this.moveStack) //avoid resetting (unwanted)
440 this.moveStack = [];
441 }
442
443 // ordering as in pieces() p,r,n,b,q,k
444 initReserves(reserveStr, pieceArray) {
445 if (!pieceArray)
446 pieceArray = ['p', 'r', 'n', 'b', 'q', 'k'];
447 const counts = reserveStr.split("").map(c => parseInt(c, 36));
448 const L = pieceArray.length;
449 this.reserve = {
450 w: ArrayFun.toObject(pieceArray, counts.slice(0, L)),
451 b: ArrayFun.toObject(pieceArray, counts.slice(L, 2 * L))
452 };
453 }
454
455 initIspawn(ispawnStr) {
456 if (ispawnStr != "-")
457 this.ispawn = ArrayFun.toObject(ispawnStr.split(","), true);
458 else
459 this.ispawn = {};
460 }
461
462 ////////////////
463 // VISUAL UTILS
464
465 getPieceWidth(rwidth) {
466 return (rwidth / this.size.y);
467 }
468
469 getReserveSquareSize(rwidth, nbR) {
470 const sqSize = this.getPieceWidth(rwidth);
471 return Math.min(sqSize, rwidth / nbR);
472 }
473
474 getReserveNumId(color, piece) {
475 return `${this.containerId}|rnum-${color}${piece}`;
476 }
477
478 getNbReservePieces(color) {
479 return (
480 Object.values(this.reserve[color]).reduce(
481 (oldV,newV) => oldV + (newV > 0 ? 1 : 0), 0)
482 );
483 }
484
485 getRankInReserve(c, p) {
486 const pieces = Object.keys(this.pieces(c, c, p));
487 const lastIndex = pieces.findIndex(pp => pp == p)
488 let toTest = pieces.slice(0, lastIndex);
489 return toTest.reduce(
490 (oldV,newV) => oldV + (this.reserve[c][newV] > 0 ? 1 : 0), 0);
491 }
492
493 static AddClass_es(elt, class_es) {
494 if (!Array.isArray(class_es))
495 class_es = [class_es];
496 class_es.forEach(cl => elt.classList.add(cl));
497 }
498
499 static RemoveClass_es(elt, class_es) {
500 if (!Array.isArray(class_es))
501 class_es = [class_es];
502 class_es.forEach(cl => elt.classList.remove(cl));
503 }
504
505 // Generally light square bottom-right
506 getSquareColorClass(x, y) {
507 return ((x+y) % 2 == 0 ? "light-square": "dark-square");
508 }
509
510 getMaxDistance(r) {
511 // Works for all rectangular boards:
512 return Math.sqrt(r.width ** 2 + r.height ** 2);
513 }
514
515 getDomPiece(x, y) {
516 return (typeof x == "string" ? this.r_pieces : this.g_pieces)[x][y];
517 }
518
519 //////////////////
520 // VISUAL METHODS
521
522 graphicalInit() {
523 const g_init = () => {
524 this.re_drawBoardElements();
525 if (!this.isDiagram && !this.mouseListeners && !this.touchListeners)
526 this.initMouseEvents();
527 };
528 let container = document.getElementById(this.containerId);
529 this.windowResizeObs = new ResizeObserver(g_init);
530 this.windowResizeObs.observe(container);
531 }
532
533 re_drawBoardElements() {
534 const board = this.getSvgChessboard();
535 const container = document.getElementById(this.containerId);
536 const rc = container.getBoundingClientRect();
537 let chessboard = container.querySelector(".chessboard");
538 chessboard.innerHTML = "";
539 chessboard.insertAdjacentHTML('beforeend', board);
540 // Compare window ratio width / height to aspectRatio:
541 const windowRatio = rc.width / rc.height;
542 let cbWidth, cbHeight;
543 const vRatio = this.size.ratio || 1;
544 if (windowRatio <= vRatio) {
545 // Limiting dimension is width:
546 cbWidth = Math.min(rc.width, 767);
547 cbHeight = cbWidth / vRatio;
548 }
549 else {
550 // Limiting dimension is height:
551 cbHeight = Math.min(rc.height, 767);
552 cbWidth = cbHeight * vRatio;
553 }
554 if (this.hasReserve && !this.isDiagram) {
555 const sqSize = cbWidth / this.size.y;
556 // NOTE: allocate space for reserves (up/down) even if they are empty
557 // Cannot use getReserveSquareSize() here, but sqSize is an upper bound.
558 if ((rc.height - cbHeight) / 2 < sqSize + 5) {
559 cbHeight = rc.height - 2 * (sqSize + 5);
560 cbWidth = cbHeight * vRatio;
561 }
562 }
563 chessboard.style.width = cbWidth + "px";
564 chessboard.style.height = cbHeight + "px";
565 // Center chessboard:
566 const spaceLeft = (rc.width - cbWidth) / 2,
567 spaceTop = (rc.height - cbHeight) / 2;
568 chessboard.style.left = spaceLeft + "px";
569 chessboard.style.top = spaceTop + "px";
570 // Give sizes instead of recomputing them,
571 // because chessboard might not be drawn yet.
572 this.setupVisualPieces({
573 width: cbWidth,
574 height: cbHeight,
575 x: spaceLeft,
576 y: spaceTop
577 });
578 }
579
580 // Get SVG board (background, no pieces)
581 getSvgChessboard() {
582 const flipped = this.flippedBoard;
583 let board = `
584 <svg
585 viewBox="0 0 ${10*this.size.y} ${10*this.size.x}"
586 class="chessboard_SVG">`;
587 for (let i=0; i < this.size.x; i++) {
588 for (let j=0; j < this.size.y; j++) {
589 if (!this.onBoard(i, j))
590 continue;
591 const ii = (flipped ? this.size.x - 1 - i : i);
592 const jj = (flipped ? this.size.y - 1 - j : j);
593 let classes = this.getSquareColorClass(ii, jj);
594 if (this.enlightened && !this.enlightened[ii][jj])
595 classes += " in-shadow";
596 // NOTE: x / y reversed because coordinates system is reversed.
597 board += `
598 <rect
599 class="${classes}"
600 id="${this.coordsToId({x: ii, y: jj})}"
601 width="10"
602 height="10"
603 x="${10*j}"
604 y="${10*i}"
605 />`;
606 }
607 }
608 board += "</svg>";
609 return board;
610 }
611
612 setupVisualPieces(r) {
613 let chessboard =
614 document.getElementById(this.containerId).querySelector(".chessboard");
615 if (!r)
616 r = chessboard.getBoundingClientRect();
617 const pieceWidth = this.getPieceWidth(r.width);
618 const addPiece = (i, j, arrName, classes) => {
619 this[arrName][i][j] = document.createElement("piece");
620 C.AddClass_es(this[arrName][i][j], classes);
621 this[arrName][i][j].style.width = pieceWidth + "px";
622 this[arrName][i][j].style.height = pieceWidth + "px";
623 let [ip, jp] = this.getPixelPosition(i, j, r);
624 // Translate coordinates to use chessboard as reference:
625 this[arrName][i][j].style.transform =
626 `translate(${ip - r.x}px,${jp - r.y}px)`;
627 chessboard.appendChild(this[arrName][i][j]);
628 };
629 const conditionalReset = (arrName) => {
630 if (this[arrName]) {
631 // Refreshing: delete old pieces first. This isn't necessary,
632 // but simpler (this method isn't called many times)
633 for (let i=0; i<this.size.x; i++) {
634 for (let j=0; j<this.size.y; j++) {
635 if (this[arrName][i][j]) {
636 this[arrName][i][j].remove();
637 this[arrName][i][j] = null;
638 }
639 }
640 }
641 }
642 else
643 this[arrName] = ArrayFun.init(this.size.x, this.size.y, null);
644 if (arrName == "d_pieces")
645 this.marks.forEach(([i, j]) => addPiece(i, j, arrName, "mark"));
646 };
647 if (this.marks)
648 conditionalReset("d_pieces");
649 conditionalReset("g_pieces");
650 for (let i=0; i < this.size.x; i++) {
651 for (let j=0; j < this.size.y; j++) {
652 if (this.board[i][j] != "") {
653 const color = this.getColor(i, j);
654 const piece = this.getPiece(i, j);
655 addPiece(i, j, "g_pieces", this.pieces(color, i, j)[piece]["class"]);
656 this.g_pieces[i][j].classList.add(V.GetColorClass(color));
657 if (this.enlightened && !this.enlightened[i][j])
658 this.g_pieces[i][j].classList.add("hidden");
659 }
660 if (this.marks && this.d_pieces[i][j]) {
661 let classes = ["mark"];
662 if (this.board[i][j] != "")
663 classes.push("transparent");
664 addPiece(i, j, "d_pieces", classes);
665 }
666 }
667 }
668 if (this.hasReserve && !this.isDiagram)
669 this.re_drawReserve(['w', 'b'], r);
670 }
671
672 // NOTE: assume this.reserve != null
673 re_drawReserve(colors, r) {
674 if (this.r_pieces) {
675 // Remove (old) reserve pieces
676 for (let c of colors) {
677 Object.keys(this.r_pieces[c]).forEach(p => {
678 this.r_pieces[c][p].remove();
679 delete this.r_pieces[c][p];
680 const numId = this.getReserveNumId(c, p);
681 document.getElementById(numId).remove();
682 });
683 }
684 }
685 else
686 this.r_pieces = { w: {}, b: {} };
687 let container = document.getElementById(this.containerId);
688 if (!r)
689 r = container.querySelector(".chessboard").getBoundingClientRect();
690 for (let c of colors) {
691 let reservesDiv = document.getElementById("reserves_" + c);
692 if (reservesDiv)
693 reservesDiv.remove();
694 if (!this.reserve[c])
695 continue;
696 const nbR = this.getNbReservePieces(c);
697 if (nbR == 0)
698 continue;
699 const sqResSize = this.getReserveSquareSize(r.width, nbR);
700 let ridx = 0;
701 const vShift = (c == this.playerColor ? r.height + 5 : -sqResSize - 5);
702 const [i0, j0] = [r.x, r.y + vShift];
703 let rcontainer = document.createElement("div");
704 rcontainer.id = "reserves_" + c;
705 rcontainer.classList.add("reserves");
706 rcontainer.style.left = i0 + "px";
707 rcontainer.style.top = j0 + "px";
708 // NOTE: +1 fix display bug on Firefox at least
709 rcontainer.style.width = (nbR * sqResSize + 1) + "px";
710 rcontainer.style.height = sqResSize + "px";
711 container.appendChild(rcontainer);
712 for (let p of Object.keys(this.reserve[c])) {
713 if (this.reserve[c][p] == 0)
714 continue;
715 let r_cell = document.createElement("div");
716 r_cell.id = this.coordsToId({x: c, y: p});
717 r_cell.classList.add("reserve-cell");
718 r_cell.style.width = sqResSize + "px";
719 r_cell.style.height = sqResSize + "px";
720 rcontainer.appendChild(r_cell);
721 let piece = document.createElement("piece");
722 C.AddClass_es(piece, this.pieces(c, c, p)[p]["class"]);
723 piece.classList.add(V.GetColorClass(c));
724 piece.style.width = "100%";
725 piece.style.height = "100%";
726 this.r_pieces[c][p] = piece;
727 r_cell.appendChild(piece);
728 let number = document.createElement("div");
729 number.textContent = this.reserve[c][p];
730 number.classList.add("reserve-num");
731 number.id = this.getReserveNumId(c, p);
732 const fontSize = "1.3em";
733 number.style.fontSize = fontSize;
734 number.style.fontSize = fontSize;
735 r_cell.appendChild(number);
736 ridx++;
737 }
738 }
739 }
740
741 updateReserve(color, piece, count) {
742 if (this.options["cannibal"] && C.CannibalKings[piece])
743 piece = "k"; //capturing cannibal king: back to king form
744 const oldCount = this.reserve[color][piece];
745 this.reserve[color][piece] = count;
746 // Redrawing is much easier if count==0 (or undefined)
747 if ([oldCount, count].some(item => !item))
748 this.re_drawReserve([color]);
749 else {
750 const numId = this.getReserveNumId(color, piece);
751 document.getElementById(numId).textContent = count;
752 }
753 }
754
755 // Resize board: no need to destroy/recreate pieces
756 rescale(mode) {
757 const container = document.getElementById(this.containerId);
758 let chessboard = container.querySelector(".chessboard");
759 const rc = container.getBoundingClientRect(),
760 r = chessboard.getBoundingClientRect();
761 const multFact = (mode == "up" ? 1.05 : 0.95);
762 let [newWidth, newHeight] = [multFact * r.width, multFact * r.height];
763 // Stay in window:
764 const vRatio = this.size.ratio || 1;
765 if (newWidth > rc.width) {
766 newWidth = rc.width;
767 newHeight = newWidth / vRatio;
768 }
769 if (newHeight > rc.height) {
770 newHeight = rc.height;
771 newWidth = newHeight * vRatio;
772 }
773 chessboard.style.width = newWidth + "px";
774 chessboard.style.height = newHeight + "px";
775 const newX = (rc.width - newWidth) / 2;
776 chessboard.style.left = newX + "px";
777 const newY = (rc.height - newHeight) / 2;
778 chessboard.style.top = newY + "px";
779 const newR = {x: newX, y: newY, width: newWidth, height: newHeight};
780 const pieceWidth = this.getPieceWidth(newWidth);
781 // NOTE: next "if" for variants which use squares filling
782 // instead of "physical", moving pieces
783 if (this.g_pieces) {
784 for (let i=0; i < this.size.x; i++) {
785 for (let j=0; j < this.size.y; j++) {
786 if (this.g_pieces[i][j]) {
787 // NOTE: could also use CSS transform "scale"
788 this.g_pieces[i][j].style.width = pieceWidth + "px";
789 this.g_pieces[i][j].style.height = pieceWidth + "px";
790 const [ip, jp] = this.getPixelPosition(i, j, newR);
791 // Translate coordinates to use chessboard as reference:
792 this.g_pieces[i][j].style.transform =
793 `translate(${ip - newX}px,${jp - newY}px)`;
794 }
795 }
796 }
797 }
798 if (this.hasReserve)
799 this.rescaleReserve(newR);
800 }
801
802 rescaleReserve(r) {
803 for (let c of ['w','b']) {
804 if (!this.reserve[c])
805 continue;
806 const nbR = this.getNbReservePieces(c);
807 if (nbR == 0)
808 continue;
809 // Resize container first
810 const sqResSize = this.getReserveSquareSize(r.width, nbR);
811 const vShift = (c == this.playerColor ? r.height + 5 : -sqResSize - 5);
812 const [i0, j0] = [r.x, r.y + vShift];
813 let rcontainer = document.getElementById("reserves_" + c);
814 rcontainer.style.left = i0 + "px";
815 rcontainer.style.top = j0 + "px";
816 rcontainer.style.width = (nbR * sqResSize + 1) + "px";
817 rcontainer.style.height = sqResSize + "px";
818 // And then reserve cells:
819 const rpieceWidth = this.getReserveSquareSize(r.width, nbR);
820 Object.keys(this.reserve[c]).forEach(p => {
821 if (this.reserve[c][p] == 0)
822 return;
823 let r_cell = document.getElementById(this.coordsToId({x: c, y: p}));
824 r_cell.style.width = sqResSize + "px";
825 r_cell.style.height = sqResSize + "px";
826 });
827 }
828 }
829
830 // Return the absolute pixel coordinates given current position.
831 // Our coordinate system differs from CSS one (x <--> y).
832 // We return here the CSS coordinates (more useful).
833 getPixelPosition(i, j, r) {
834 if (i < 0 || j < 0)
835 return [0, 0]; //piece vanishes
836 let x, y;
837 if (typeof i == "string") {
838 // Reserves: need to know the rank of piece
839 const nbR = this.getNbReservePieces(i);
840 const rsqSize = this.getReserveSquareSize(r.width, nbR);
841 x = this.getRankInReserve(i, j) * rsqSize;
842 y = (this.playerColor == i ? y = r.height + 5 : - 5 - rsqSize);
843 }
844 else {
845 const sqSize = r.width / this.size.y;
846 const flipped = this.flippedBoard;
847 x = (flipped ? this.size.y - 1 - j : j) * sqSize;
848 y = (flipped ? this.size.x - 1 - i : i) * sqSize;
849 }
850 return [r.x + x, r.y + y];
851 }
852
853 initMouseEvents() {
854 let container = document.getElementById(this.containerId);
855 let chessboard = container.querySelector(".chessboard");
856
857 const getOffset = e => {
858 if (e.clientX)
859 // Mouse
860 return {x: e.clientX, y: e.clientY};
861 let touchLocation = null;
862 if (e.targetTouches && e.targetTouches.length >= 1)
863 // Touch screen, dragstart
864 touchLocation = e.targetTouches[0];
865 else if (e.changedTouches && e.changedTouches.length >= 1)
866 // Touch screen, dragend
867 touchLocation = e.changedTouches[0];
868 if (touchLocation)
869 return {x: touchLocation.clientX, y: touchLocation.clientY};
870 return {x: 0, y: 0}; //shouldn't reach here =)
871 }
872
873 const centerOnCursor = (piece, e) => {
874 const centerShift = this.getPieceWidth(r.width) / 2;
875 const offset = getOffset(e);
876 piece.style.left = (offset.x - centerShift) + "px";
877 piece.style.top = (offset.y - centerShift) + "px";
878 }
879
880 let start = null,
881 r = null,
882 startPiece, curPiece = null,
883 pieceWidth;
884 const mousedown = (e) => {
885 // Disable zoom on smartphones:
886 if (e.touches && e.touches.length > 1)
887 e.preventDefault();
888 r = chessboard.getBoundingClientRect();
889 pieceWidth = this.getPieceWidth(r.width);
890 const cd = this.idToCoords(e.target.id);
891 if (cd) {
892 const move = this.doClick(cd);
893 if (move)
894 this.buildMoveStack(move, r);
895 else if (!this.clickOnly) {
896 const [x, y] = Object.values(cd);
897 if (typeof x != "number")
898 startPiece = this.r_pieces[x][y];
899 else
900 startPiece = this.g_pieces[x][y];
901 if (startPiece && this.canIplay(x, y)) {
902 e.preventDefault();
903 start = cd;
904 curPiece = startPiece.cloneNode();
905 curPiece.style.transform = "none";
906 curPiece.style.zIndex = 5;
907 curPiece.style.width = pieceWidth + "px";
908 curPiece.style.height = pieceWidth + "px";
909 centerOnCursor(curPiece, e);
910 container.appendChild(curPiece);
911 startPiece.style.opacity = "0.4";
912 chessboard.style.cursor = "none";
913 }
914 }
915 }
916 };
917
918 const mousemove = (e) => {
919 if (start) {
920 e.preventDefault();
921 centerOnCursor(curPiece, e);
922 }
923 else if (e.changedTouches && e.changedTouches.length >= 1)
924 // Attempt to prevent horizontal swipe...
925 e.preventDefault();
926 };
927
928 const mouseup = (e) => {
929 if (!start)
930 return;
931 const [x, y] = [start.x, start.y];
932 start = null;
933 e.preventDefault();
934 chessboard.style.cursor = "pointer";
935 startPiece.style.opacity = "1";
936 const offset = getOffset(e);
937 const landingElt = document.elementFromPoint(offset.x, offset.y);
938 const cd =
939 (landingElt ? this.idToCoords(landingElt.id) : undefined);
940 if (cd) {
941 // NOTE: clearly suboptimal, but much easier, and not a big deal.
942 const potentialMoves = this.getPotentialMovesFrom([x, y])
943 .filter(m => m.end.x == cd.x && m.end.y == cd.y);
944 const moves = this.filterValid(potentialMoves);
945 if (moves.length >= 2)
946 this.showChoices(moves, r);
947 else if (moves.length == 1)
948 this.buildMoveStack(moves[0], r);
949 }
950 curPiece.remove();
951 };
952
953 const resize = (e) => this.rescale(e.deltaY < 0 ? "up" : "down");
954
955 if ('onmousedown' in window) {
956 this.mouseListeners = [
957 {type: "mousedown", listener: mousedown},
958 {type: "mousemove", listener: mousemove},
959 {type: "mouseup", listener: mouseup},
960 {type: "wheel", listener: resize}
961 ];
962 this.mouseListeners.forEach(ml => {
963 document.addEventListener(ml.type, ml.listener);
964 });
965 }
966 if ('ontouchstart' in window) {
967 this.touchListeners = [
968 {type: "touchstart", listener: mousedown},
969 {type: "touchmove", listener: mousemove},
970 {type: "touchend", listener: mouseup}
971 ];
972 this.touchListeners.forEach(tl => {
973 // https://stackoverflow.com/a/42509310/12660887
974 document.addEventListener(tl.type, tl.listener, {passive: false});
975 });
976 }
977 // TODO: onpointerdown/move/up ? See reveal.js /controllers/touch.js
978 }
979
980 // NOTE: not called if isDiagram
981 removeListeners() {
982 let container = document.getElementById(this.containerId);
983 this.windowResizeObs.unobserve(container);
984 if ('onmousedown' in window) {
985 this.mouseListeners.forEach(ml => {
986 document.removeEventListener(ml.type, ml.listener);
987 });
988 }
989 if ('ontouchstart' in window) {
990 this.touchListeners.forEach(tl => {
991 // https://stackoverflow.com/a/42509310/12660887
992 document.removeEventListener(tl.type, tl.listener);
993 });
994 }
995 }
996
997 showChoices(moves, r) {
998 let container = document.getElementById(this.containerId);
999 let chessboard = container.querySelector(".chessboard");
1000 let choices = document.createElement("div");
1001 choices.id = "choices";
1002 if (!r)
1003 r = chessboard.getBoundingClientRect();
1004 choices.style.width = r.width + "px";
1005 choices.style.height = r.height + "px";
1006 choices.style.left = r.x + "px";
1007 choices.style.top = r.y + "px";
1008 chessboard.style.opacity = "0.5";
1009 container.appendChild(choices);
1010 const squareWidth = r.width / this.size.y;
1011 const firstUpLeft = (r.width - (moves.length * squareWidth)) / 2;
1012 const firstUpTop = (r.height - squareWidth) / 2;
1013 const color = moves[0].appear[0].c;
1014 const callback = (m) => {
1015 chessboard.style.opacity = "1";
1016 container.removeChild(choices);
1017 this.buildMoveStack(m, r);
1018 }
1019 for (let i=0; i < moves.length; i++) {
1020 let choice = document.createElement("div");
1021 choice.classList.add("choice");
1022 choice.style.width = squareWidth + "px";
1023 choice.style.height = squareWidth + "px";
1024 choice.style.left = (firstUpLeft + i * squareWidth) + "px";
1025 choice.style.top = firstUpTop + "px";
1026 choice.style.backgroundColor = "lightyellow";
1027 choice.onclick = () => callback(moves[i]);
1028 const piece = document.createElement("piece");
1029 const cdisp = moves[i].choice || moves[i].appear[0].p;
1030 C.AddClass_es(piece,
1031 this.pieces(color, moves[i].end.x, moves[i].end.y)[cdisp]["class"]);
1032 piece.classList.add(V.GetColorClass(color));
1033 piece.style.width = "100%";
1034 piece.style.height = "100%";
1035 choice.appendChild(piece);
1036 choices.appendChild(choice);
1037 }
1038 }
1039
1040 displayMessage(elt, msg, classe_s, timeout) {
1041 if (elt)
1042 // Fixed element, e.g. for Dice Chess
1043 elt.innerHTML = msg;
1044 else {
1045 // Temporary div (Chakart, Apocalypse...)
1046 let divMsg = document.createElement("div");
1047 C.AddClass_es(divMsg, classe_s);
1048 divMsg.innerHTML = msg;
1049 let container = document.getElementById(this.containerId);
1050 container.appendChild(divMsg);
1051 setTimeout(() => container.removeChild(divMsg), timeout);
1052 }
1053 }
1054
1055 ////////////////
1056 // DARK METHODS
1057
1058 updateEnlightened() {
1059 this.oldEnlightened = this.enlightened;
1060 this.enlightened = ArrayFun.init(this.size.x, this.size.y, false);
1061 // Add pieces positions + all squares reachable by moves (includes Zen):
1062 for (let x=0; x<this.size.x; x++) {
1063 for (let y=0; y<this.size.y; y++) {
1064 if (this.board[x][y] != "" && this.getColor(x, y) == this.playerColor)
1065 {
1066 this.enlightened[x][y] = true;
1067 this.getPotentialMovesFrom([x, y]).forEach(m => {
1068 this.enlightened[m.end.x][m.end.y] = true;
1069 });
1070 }
1071 }
1072 }
1073 if (this.epSquare)
1074 this.enlightEnpassant();
1075 }
1076
1077 // Include square of the en-passant capturing square:
1078 enlightEnpassant() {
1079 // NOTE: shortcut, pawn has only one attack type, doesn't depend on square
1080 // TODO: (0, 0) is wrong, would need to place an attacker here...
1081 const steps = this.pieces(this.playerColor, 0, 0)["p"].attack[0].steps;
1082 for (let step of steps) {
1083 const x = this.epSquare.x - step[0], //NOTE: epSquare.x not on edge
1084 y = this.getY(this.epSquare.y - step[1]);
1085 if (
1086 this.onBoard(x, y) &&
1087 this.getColor(x, y) == this.playerColor &&
1088 this.getPieceType(x, y) == "p"
1089 ) {
1090 this.enlightened[x][this.epSquare.y] = true;
1091 break;
1092 }
1093 }
1094 }
1095
1096 // Apply diff this.enlightened --> oldEnlightened on board
1097 graphUpdateEnlightened() {
1098 let chessboard =
1099 document.getElementById(this.containerId).querySelector(".chessboard");
1100 const r = chessboard.getBoundingClientRect();
1101 const pieceWidth = this.getPieceWidth(r.width);
1102 for (let x=0; x<this.size.x; x++) {
1103 for (let y=0; y<this.size.y; y++) {
1104 if (!this.enlightened[x][y] && this.oldEnlightened[x][y]) {
1105 let elt = document.getElementById(this.coordsToId({x: x, y: y}));
1106 elt.classList.add("in-shadow");
1107 if (this.g_pieces[x][y])
1108 this.g_pieces[x][y].classList.add("hidden");
1109 }
1110 else if (this.enlightened[x][y] && !this.oldEnlightened[x][y]) {
1111 let elt = document.getElementById(this.coordsToId({x: x, y: y}));
1112 elt.classList.remove("in-shadow");
1113 if (this.g_pieces[x][y])
1114 this.g_pieces[x][y].classList.remove("hidden");
1115 }
1116 }
1117 }
1118 }
1119
1120 //////////////
1121 // BASIC UTILS
1122
1123 get size() {
1124 return {
1125 x: 8,
1126 y: 8,
1127 ratio: 1 //for rectangular board = y / x (optional, 1 = default)
1128 };
1129 }
1130
1131 // Color of thing on square (i,j). '' if square is empty
1132 getColor(i, j) {
1133 if (typeof i == "string")
1134 return i; //reserves
1135 return this.board[i][j].charAt(0);
1136 }
1137
1138 static GetColorClass(c) {
1139 if (c == 'w')
1140 return "white";
1141 if (c == 'b')
1142 return "black";
1143 return "other-color"; //unidentified color
1144 }
1145
1146 // Piece on i,j. '' if square is empty
1147 getPiece(i, j) {
1148 if (typeof j == "string")
1149 return j; //reserves
1150 return this.board[i][j].charAt(1);
1151 }
1152
1153 // Piece type on square (i,j)
1154 getPieceType(x, y, p) {
1155 if (!p)
1156 p = this.getPiece(x, y);
1157 return this.pieces(this.getColor(x, y), x, y)[p].moveas || p;
1158 }
1159
1160 isKing(x, y, p) {
1161 if (!p)
1162 p = this.getPiece(x, y);
1163 if (!this.options["cannibal"])
1164 return p == 'k';
1165 return !!C.CannibalKings[p];
1166 }
1167
1168 static GetOppTurn(color) {
1169 return (color == 'w' ? 'b' : 'w');
1170 }
1171
1172 // Get opponent color(s): may differ from turn (e.g. Checkered)
1173 getOppCols(color) {
1174 return (color == "w" ? "b" : "w");
1175 }
1176
1177 // Is (x,y) on the chessboard?
1178 onBoard(x, y) {
1179 return (x >= 0 && x < this.size.x &&
1180 y >= 0 && y < this.size.y);
1181 }
1182
1183 // Am I allowed to move thing at square x,y ?
1184 canIplay(x, y) {
1185 return (this.playerColor == this.turn && this.getColor(x, y) == this.turn);
1186 }
1187
1188 ////////////////////////
1189 // PIECES SPECIFICATIONS
1190
1191 getPawnShift(color) {
1192 return (color == "w" ? -1 : 1);
1193 }
1194 isPawnInitRank(x, color) {
1195 return (color == 'w' && x >= 6) || (color == 'b' && x <= 1);
1196 }
1197
1198 pieces(color, x, y) {
1199 const pawnShift = this.getPawnShift(color || 'w');
1200 return {
1201 'p': {
1202 "class": "pawn",
1203 moves: [
1204 {
1205 steps: [[pawnShift, 0]],
1206 range: (this.isPawnInitRank(x, color) ? 2 : 1)
1207 }
1208 ],
1209 attack: [
1210 {
1211 steps: [[pawnShift, 1], [pawnShift, -1]],
1212 range: 1
1213 }
1214 ]
1215 },
1216 'r': {
1217 "class": "rook",
1218 both: [
1219 {steps: [[0, 1], [0, -1], [1, 0], [-1, 0]]}
1220 ]
1221 },
1222 'n': {
1223 "class": "knight",
1224 both: [
1225 {
1226 steps: [
1227 [1, 2], [1, -2], [-1, 2], [-1, -2],
1228 [2, 1], [-2, 1], [2, -1], [-2, -1]
1229 ],
1230 range: 1
1231 }
1232 ]
1233 },
1234 'b': {
1235 "class": "bishop",
1236 both: [
1237 {steps: [[1, 1], [1, -1], [-1, 1], [-1, -1]]}
1238 ]
1239 },
1240 'q': {
1241 "class": "queen",
1242 both: [
1243 {
1244 steps: [
1245 [0, 1], [0, -1], [1, 0], [-1, 0],
1246 [1, 1], [1, -1], [-1, 1], [-1, -1]
1247 ]
1248 }
1249 ]
1250 },
1251 'k': {
1252 "class": "king",
1253 both: [
1254 {
1255 steps: [
1256 [0, 1], [0, -1], [1, 0], [-1, 0],
1257 [1, 1], [1, -1], [-1, 1], [-1, -1]
1258 ],
1259 range: 1
1260 }
1261 ]
1262 },
1263 // Cannibal kings:
1264 '!': {"class": "king-pawn", moveas: "p"},
1265 '#': {"class": "king-rook", moveas: "r"},
1266 '$': {"class": "king-knight", moveas: "n"},
1267 '%': {"class": "king-bishop", moveas: "b"},
1268 '*': {"class": "king-queen", moveas: "q"}
1269 };
1270 }
1271
1272 // NOTE: using special symbols to not interfere with variants' pieces codes
1273 static get CannibalKings() {
1274 return {
1275 "!": "p",
1276 "#": "r",
1277 "$": "n",
1278 "%": "b",
1279 "*": "q",
1280 "k": "k"
1281 };
1282 }
1283
1284 static get CannibalKingCode() {
1285 return {
1286 "p": "!",
1287 "r": "#",
1288 "n": "$",
1289 "b": "%",
1290 "q": "*",
1291 "k": "k"
1292 };
1293 }
1294
1295 //////////////////////////
1296 // MOVES GENERATION UTILS
1297
1298 // For Cylinder: get Y coordinate
1299 getY(y) {
1300 if (!this.options["cylinder"])
1301 return y;
1302 let res = y % this.size.y;
1303 if (res < 0)
1304 res += this.size.y;
1305 return res;
1306 }
1307 // Circular?
1308 getX(x) {
1309 return x; //generally, no
1310 }
1311
1312 increment([x, y], step) {
1313 return [
1314 this.getX(x + step[0]),
1315 this.getY(y + step[1])
1316 ];
1317 }
1318
1319 getSegments(curSeg, segStart, segEnd) {
1320 if (curSeg.length == 0)
1321 return undefined;
1322 let segments = JSON.parse(JSON.stringify(curSeg)); //not altering
1323 segments.push([[segStart[0], segStart[1]], [segEnd[0], segEnd[1]]]);
1324 return segments;
1325 }
1326
1327 getStepSpec(color, x, y, piece) {
1328 let pieceType = piece;
1329 let allSpecs = this.pieces(color, x, y);
1330 if (!piece)
1331 pieceType = this.getPieceType(x, y);
1332 else if (allSpecs[piece].moveas)
1333 pieceType = allSpecs[piece].moveas;
1334 let res = allSpecs[pieceType];
1335 if (!res["both"])
1336 res.both = [];
1337 if (!res["moves"])
1338 res.moves = [];
1339 if (!res["attack"])
1340 res.attack = [];
1341 return res;
1342 }
1343
1344 // Can thing on square1 capture thing on square2?
1345 canTake([x1, y1], [x2, y2]) {
1346 return this.getColor(x1, y1) !== this.getColor(x2, y2);
1347 }
1348
1349 // Teleport & Recycle. Assumption: color(x1,y1) == color(x2,y2)
1350 canSelfTake([x1, y1], [x2, y2]) {
1351 return !this.isKing(x2, y2);
1352 }
1353
1354 canStepOver(i, j, p) {
1355 // In some variants, objects on boards don't stop movement (Chakart)
1356 return this.board[i][j] == "";
1357 }
1358
1359 canDrop([c, p], [i, j]) {
1360 return (
1361 this.board[i][j] == "" &&
1362 (!this.enlightened || this.enlightened[i][j]) &&
1363 (
1364 p != "p" ||
1365 (c == 'w' && i < this.size.x - 1) ||
1366 (c == 'b' && i > 0)
1367 )
1368 );
1369 }
1370
1371 // For Madrasi:
1372 // (redefined in Baroque etc, where Madrasi condition doesn't make sense)
1373 isImmobilized([x, y]) {
1374 if (!this.options["madrasi"])
1375 return false;
1376 const color = this.getColor(x, y);
1377 const oppCols = this.getOppCols(color);
1378 const piece = this.getPieceType(x, y);
1379 const stepSpec = this.getStepSpec(color, x, y, piece);
1380 const attacks = stepSpec.both.concat(stepSpec.attack);
1381 for (let a of attacks) {
1382 outerLoop: for (let step of a.steps) {
1383 let [i, j] = this.increment([x, y], step);
1384 let stepCounter = 0;
1385 while (this.onBoard(i, j) && this.board[i][j] == "") {
1386 if (a.range <= stepCounter++)
1387 continue outerLoop;
1388 [i, j] = this.increment([i, j], step);
1389 }
1390 if (
1391 this.onBoard(i, j) &&
1392 oppCols.includes(this.getColor(i, j)) &&
1393 this.getPieceType(i, j) == piece
1394 ) {
1395 return true;
1396 }
1397 }
1398 }
1399 return false;
1400 }
1401
1402 // Stop at the first capture found
1403 atLeastOneCapture(color) {
1404 const allowed = (sq1, sq2) => {
1405 return (
1406 // NOTE: canTake is reversed for Zen.
1407 // Generally ok because of the symmetry. TODO?
1408 this.canTake(sq1, sq2) &&
1409 this.filterValid(
1410 [this.getBasicMove(sq1, sq2)]).length >= 1
1411 );
1412 };
1413 for (let i=0; i<this.size.x; i++) {
1414 for (let j=0; j<this.size.y; j++) {
1415 if (this.getColor(i, j) == color) {
1416 if (
1417 (
1418 !this.options["zen"] &&
1419 this.findDestSquares(
1420 [i, j],
1421 {
1422 attackOnly: true,
1423 one: true,
1424 },
1425 allowed
1426 )
1427 )
1428 ||
1429 (
1430 (
1431 this.options["zen"] &&
1432 this.findCapturesOn(
1433 [i, j],
1434 {one: true},
1435 allowed
1436 )
1437 )
1438 )
1439 ) {
1440 return true;
1441 }
1442 }
1443 }
1444 }
1445 return false;
1446 }
1447
1448 compatibleStep([x1, y1], [x2, y2], step, range) {
1449 const epsilon = 1e-7; //arbitrary small value
1450 let shifts = [0];
1451 if (this.options["cylinder"])
1452 Array.prototype.push.apply(shifts, [-this.size.y, this.size.y]);
1453 for (let sh of shifts) {
1454 const rx = (x2 - x1) / step[0],
1455 ry = (y2 + sh - y1) / step[1];
1456 if (
1457 // Zero step but non-zero interval => impossible
1458 (!Number.isFinite(rx) && !Number.isNaN(rx)) ||
1459 (!Number.isFinite(ry) && !Number.isNaN(ry)) ||
1460 // Negative number of step (impossible)
1461 (rx < 0 || ry < 0) ||
1462 // Not the same number of steps in both directions:
1463 (!Number.isNaN(rx) && !Number.isNaN(ry) && Math.abs(rx - ry) > epsilon)
1464 ) {
1465 continue;
1466 }
1467 let distance = (Number.isNaN(rx) ? ry : rx);
1468 if (Math.abs(distance - Math.round(distance)) > epsilon)
1469 continue;
1470 distance = Math.round(distance); //in case of (numerical...)
1471 if (!range || range >= distance)
1472 return true;
1473 }
1474 return false;
1475 }
1476
1477 ////////////////////
1478 // MOVES GENERATION
1479
1480 getDropMovesFrom([c, p]) {
1481 // NOTE: by design, this.reserve[c][p] >= 1 on user click
1482 // (but not necessarily otherwise: atLeastOneMove() etc)
1483 if (this.reserve[c][p] == 0)
1484 return [];
1485 let moves = [];
1486 for (let i=0; i<this.size.x; i++) {
1487 for (let j=0; j<this.size.y; j++) {
1488 if (this.onBoard(i, j) && this.canDrop([c, p], [i, j])) {
1489 let mv = new Move({
1490 start: {x: c, y: p},
1491 end: {x: i, y: j},
1492 appear: [new PiPo({x: i, y: j, c: c, p: p})],
1493 vanish: []
1494 });
1495 if (this.board[i][j] != "") {
1496 mv.vanish.push(new PiPo({
1497 x: i,
1498 y: j,
1499 c: this.getColor(i, j),
1500 p: this.getPiece(i, j)
1501 }));
1502 }
1503 moves.push(mv);
1504 }
1505 }
1506 }
1507 return moves;
1508 }
1509
1510 // All possible moves from selected square
1511 // TODO: generalize usage if arg "color" (e.g. Checkered)
1512 getPotentialMovesFrom([x, y], color) {
1513 if (this.subTurnTeleport == 2)
1514 return [];
1515 if (typeof x == "string")
1516 return this.getDropMovesFrom([x, y]);
1517 if (this.isImmobilized([x, y]))
1518 return [];
1519 const piece = this.getPieceType(x, y);
1520 let moves = this.getPotentialMovesOf(piece, [x, y]);
1521 if (piece == "p" && this.hasEnpassant && this.epSquare)
1522 Array.prototype.push.apply(moves, this.getEnpassantCaptures([x, y]));
1523 if (
1524 this.isKing(0, 0, piece) && this.hasCastle &&
1525 this.castleFlags[color || this.turn].some(v => v < this.size.y)
1526 ) {
1527 Array.prototype.push.apply(moves, this.getCastleMoves([x, y]));
1528 }
1529 return this.postProcessPotentialMoves(moves);
1530 }
1531
1532 postProcessPotentialMoves(moves) {
1533 if (moves.length == 0)
1534 return [];
1535 const color = this.getColor(moves[0].start.x, moves[0].start.y);
1536 const oppCols = this.getOppCols(color);
1537
1538 if (this.options["capture"] && this.atLeastOneCapture(color))
1539 moves = this.capturePostProcess(moves, oppCols);
1540
1541 if (this.options["atomic"])
1542 moves = this.atomicPostProcess(moves, color, oppCols);
1543
1544 if (
1545 moves.length > 0 &&
1546 this.getPieceType(moves[0].start.x, moves[0].start.y) == "p"
1547 ) {
1548 moves = this.pawnPostProcess(moves, color, oppCols);
1549 }
1550
1551 if (this.options["cannibal"] && this.options["rifle"])
1552 // In this case a rifle-capture from last rank may promote a pawn
1553 moves = this.riflePromotePostProcess(moves, color);
1554
1555 return moves;
1556 }
1557
1558 capturePostProcess(moves, oppCols) {
1559 // Filter out non-capturing moves (not using m.vanish because of
1560 // self captures of Recycle and Teleport).
1561 return moves.filter(m => {
1562 return (
1563 this.board[m.end.x][m.end.y] != "" &&
1564 oppCols.includes(this.getColor(m.end.x, m.end.y))
1565 );
1566 });
1567 }
1568
1569 atomicPostProcess(moves, color, oppCols) {
1570 moves.forEach(m => {
1571 if (
1572 this.board[m.end.x][m.end.y] != "" &&
1573 oppCols.includes(this.getColor(m.end.x, m.end.y))
1574 ) {
1575 // Explosion!
1576 let steps = [
1577 [-1, -1],
1578 [-1, 0],
1579 [-1, 1],
1580 [0, -1],
1581 [0, 1],
1582 [1, -1],
1583 [1, 0],
1584 [1, 1]
1585 ];
1586 let mNext = new Move({
1587 start: m.end,
1588 end: m.end,
1589 appear: [],
1590 vanish: []
1591 });
1592 for (let step of steps) {
1593 let [x, y] = this.increment([m.end.x, m.end.y], step);
1594 if (
1595 this.onBoard(x, y) &&
1596 this.board[x][y] != "" &&
1597 (x != m.start.x || y != m.start.y) &&
1598 this.getPieceType(x, y) != "p"
1599 ) {
1600 mNext.vanish.push(
1601 new PiPo({
1602 p: this.getPiece(x, y),
1603 c: this.getColor(x, y),
1604 x: x,
1605 y: y
1606 })
1607 );
1608 }
1609 }
1610 if (!this.options["rifle"]) {
1611 // The moving piece also vanish
1612 mNext.vanish.unshift(
1613 new PiPo({
1614 x: m.end.x,
1615 y: m.end.y,
1616 c: color,
1617 p: this.getPiece(m.start.x, m.start.y)
1618 })
1619 );
1620 }
1621 m.next = mNext;
1622 }
1623 });
1624 return moves;
1625 }
1626
1627 pawnPostProcess(moves, color, oppCols) {
1628 let moreMoves = [];
1629 const lastRank = (color == "w" ? 0 : this.size.x - 1);
1630 const initPiece = this.getPiece(moves[0].start.x, moves[0].start.y);
1631 moves.forEach(m => {
1632 const [x1, y1] = [m.start.x, m.start.y];
1633 const [x2, y2] = [m.end.x, m.end.y];
1634 const promotionOk = (
1635 x2 == lastRank &&
1636 (!this.options["rifle"] || this.board[x2][y2] == "")
1637 );
1638 if (!promotionOk)
1639 return; //nothing to do
1640 if (this.options["pawnfall"]) {
1641 m.appear.shift();
1642 return;
1643 }
1644 let finalPieces;
1645 if (
1646 this.options["cannibal"] &&
1647 this.board[x2][y2] != "" &&
1648 oppCols.includes(this.getColor(x2, y2))
1649 ) {
1650 finalPieces = [this.getPieceType(x2, y2)];
1651 }
1652 else
1653 finalPieces = this.pawnPromotions;
1654 m.appear[0].p = finalPieces[0];
1655 if (initPiece == "!") //cannibal king-pawn
1656 m.appear[0].p = C.CannibalKingCode[finalPieces[0]];
1657 for (let i=1; i<finalPieces.length; i++) {
1658 let newMove = JSON.parse(JSON.stringify(m));
1659 const piece = finalPieces[i];
1660 m.appear[0].p = (initPiece != "!" ? piece : C.CannibalKingCode[piece]);
1661 moreMoves.push(newMove);
1662 }
1663 });
1664 return moves.concat(moreMoves);
1665 }
1666
1667 riflePromotePostProcess(moves, color) {
1668 const lastRank = (color == "w" ? 0 : this.size.x - 1);
1669 let newMoves = [];
1670 moves.forEach(m => {
1671 if (
1672 m.start.x == lastRank &&
1673 m.appear.length >= 1 &&
1674 m.appear[0].p == "p" &&
1675 m.appear[0].x == m.start.x &&
1676 m.appear[0].y == m.start.y
1677 ) {
1678 m.appear[0].p = this.pawnPromotions[0];
1679 for (let i=1; i<this.pawnPromotions.length; i++) {
1680 let newMv = JSON.parse(JSON.stringify(m));
1681 newMv.appear[0].p = this.pawnPromotions[i];
1682 newMoves.push(newMv);
1683 }
1684 }
1685 });
1686 return moves.concat(newMoves);
1687 }
1688
1689 // Generic method to find possible moves of "sliding or jumping" pieces
1690 getPotentialMovesOf(piece, [x, y]) {
1691 const color = this.getColor(x, y);
1692 const stepSpec = this.getStepSpec(color, x, y, piece);
1693 let squares = [];
1694 if (stepSpec.attack) {
1695 squares = this.findDestSquares(
1696 [x, y],
1697 {
1698 attackOnly: true,
1699 stepSpec: stepSpec
1700 },
1701 ([i1, j1], [i2, j2]) => {
1702 return (
1703 (!this.options["zen"] || this.isKing(i2, j2)) &&
1704 this.canTake([i1, j1], [i2, j2])
1705 );
1706 }
1707 );
1708 }
1709 const noSpecials = this.findDestSquares(
1710 [x, y],
1711 {
1712 moveOnly: !!stepSpec.attack || this.options["zen"],
1713 stepSpec: stepSpec
1714 }
1715 );
1716 Array.prototype.push.apply(squares, noSpecials);
1717 if (this.options["zen"]) {
1718 let zenCaptures = this.findCapturesOn(
1719 [x, y],
1720 {}, //byCol: default is ok
1721 ([i1, j1], [i2, j2]) =>
1722 !this.isKing(i1, j1) && this.canTake([i2, j2], [i1, j1])
1723 );
1724 // Technical step: segments (if any) are reversed
1725 zenCaptures.forEach(z => {
1726 if (!!z.segments)
1727 z.segments = z.segments.reverse().map(s => s.reverse())
1728 });
1729 Array.prototype.push.apply(squares, zenCaptures);
1730 }
1731 if (this.hasSelfCaptures) {
1732 const selfCaptures = this.findDestSquares(
1733 [x, y],
1734 {
1735 attackOnly: true,
1736 stepSpec: stepSpec
1737 },
1738 ([i1, j1], [i2, j2]) => {
1739 return (
1740 this.getColor(i2, j2) == color &&
1741 this.canSelfTake([i1, j1], [i2, j2])
1742 );
1743 }
1744 );
1745 Array.prototype.push.apply(squares, selfCaptures);
1746 }
1747 return squares.map(s => {
1748 let mv = this.getBasicMove([x, y], s.sq);
1749 if (!!s.segments)
1750 mv.segments = s.segments;
1751 return mv;
1752 });
1753 }
1754
1755 findDestSquares([x, y], o, allowed) {
1756 if (!allowed)
1757 allowed = (sq1, sq2) => this.canTake(sq1, sq2);
1758 const apparentPiece = this.getPiece(x, y); //how it looks
1759 let res = [];
1760 // Next 3 for Cylinder mode or circular (useless otherwise)
1761 let explored = {};
1762 let segments = [];
1763 let segStart = [];
1764 const addSquare = ([i, j]) => {
1765 let elt = {sq: [i, j]};
1766 if (segments.length >= 1)
1767 elt.segments = this.getSegments(segments, segStart, [i, j]);
1768 res.push(elt);
1769 };
1770 const exploreSteps = (stepArray, mode) => {
1771 for (let s of stepArray) {
1772 outerLoop: for (let step of s.steps) {
1773 segments = [];
1774 segStart = [x, y];
1775 let [i, j] = [x, y];
1776 let stepCounter = 0;
1777 while (
1778 this.onBoard(i, j) &&
1779 ((i == x && j == y) || this.canStepOver(i, j, apparentPiece))
1780 ) {
1781 if (!explored[i + "." + j] && (i != x || j != y)) {
1782 explored[i + "." + j] = true;
1783 if (
1784 !o.captureTarget ||
1785 (o.captureTarget[0] == i && o.captureTarget[1] == j)
1786 ) {
1787 if (o.one && mode != "attack")
1788 return true;
1789 if (mode != "attack")
1790 addSquare(!o.captureTarget ? [i, j] : [x, y]);
1791 if (o.captureTarget)
1792 return res[0];
1793 }
1794 }
1795 if (s.range <= stepCounter++)
1796 continue outerLoop;
1797 const oldIJ = [i, j];
1798 [i, j] = this.increment([i, j], step);
1799 if (Math.abs(j - oldIJ[1]) > 1 || Math.abs(i - oldIJ[0]) > 1) {
1800 // Boundary between segments (cylinder or circular mode)
1801 segments.push([[segStart[0], segStart[1]], oldIJ]);
1802 segStart = [i, j];
1803 }
1804 }
1805 if (!this.onBoard(i, j))
1806 continue;
1807 const pieceIJ = this.getPieceType(i, j);
1808 if (!explored[i + "." + j]) {
1809 explored[i + "." + j] = true;
1810 if (allowed([x, y], [i, j])) {
1811 if (o.one && mode != "moves")
1812 return true;
1813 if (mode != "moves")
1814 addSquare(!o.captureTarget ? [i, j] : [x, y]);
1815 if (
1816 o.captureTarget &&
1817 o.captureTarget[0] == i && o.captureTarget[1] == j
1818 ) {
1819 return res[0];
1820 }
1821 }
1822 }
1823 }
1824 }
1825 return undefined; //default, but let's explicit it
1826 };
1827 if (o.captureTarget)
1828 return exploreSteps(o.captureSteps, "attack");
1829 else {
1830 const stepSpec =
1831 o.stepSpec || this.getStepSpec(this.getColor(x, y), x, y);
1832 let outOne = false;
1833 if (!o.attackOnly)
1834 outOne = exploreSteps(stepSpec.both.concat(stepSpec.moves), "moves");
1835 if (!outOne && !o.moveOnly)
1836 outOne = exploreSteps(stepSpec.both.concat(stepSpec.attack), "attack");
1837 return (o.one ? outOne : res);
1838 }
1839 }
1840
1841 // Search for enemy (or not) pieces attacking [x, y]
1842 findCapturesOn([x, y], o, allowed) {
1843 if (!o.byCol)
1844 o.byCol = this.getOppCols(this.getColor(x, y) || this.turn);
1845 let res = [];
1846 for (let i=0; i<this.size.x; i++) {
1847 for (let j=0; j<this.size.y; j++) {
1848 const colIJ = this.getColor(i, j);
1849 if (
1850 this.board[i][j] != "" &&
1851 o.byCol.includes(colIJ) &&
1852 !this.isImmobilized([i, j])
1853 ) {
1854 const apparentPiece = this.getPiece(i, j);
1855 // Quick check: does this potential attacker target x,y ?
1856 if (this.canStepOver(x, y, apparentPiece))
1857 continue;
1858 const stepSpec = this.getStepSpec(colIJ, i, j);
1859 const attacks = stepSpec.attack.concat(stepSpec.both);
1860 for (let a of attacks) {
1861 for (let s of a.steps) {
1862 // Quick check: if step isn't compatible, don't even try
1863 if (!this.compatibleStep([i, j], [x, y], s, a.range))
1864 continue;
1865 // Finally verify that nothing stand in-between
1866 const out = this.findDestSquares(
1867 [i, j],
1868 {
1869 captureTarget: [x, y],
1870 captureSteps: [{steps: [s], range: a.range}],
1871 },
1872 allowed
1873 );
1874 if (out) {
1875 if (o.one)
1876 return true;
1877 res.push(out);
1878 }
1879 }
1880 }
1881 }
1882 }
1883 }
1884 return (o.one ? false : res);
1885 }
1886
1887 // Build a regular move from its initial and destination squares.
1888 // tr: transformation
1889 getBasicMove([sx, sy], [ex, ey], tr) {
1890 const initColor = this.getColor(sx, sy);
1891 const initPiece = this.getPiece(sx, sy);
1892 const destColor = (this.board[ex][ey] != "" ? this.getColor(ex, ey) : "");
1893 let mv = new Move({
1894 appear: [],
1895 vanish: [],
1896 start: {x: sx, y: sy},
1897 end: {x: ex, y: ey}
1898 });
1899 if (
1900 !this.options["rifle"] ||
1901 this.board[ex][ey] == "" ||
1902 destColor == initColor //Recycle, Teleport
1903 ) {
1904 mv.appear = [
1905 new PiPo({
1906 x: ex,
1907 y: ey,
1908 c: !!tr ? tr.c : initColor,
1909 p: !!tr ? tr.p : initPiece
1910 })
1911 ];
1912 mv.vanish = [
1913 new PiPo({
1914 x: sx,
1915 y: sy,
1916 c: initColor,
1917 p: initPiece
1918 })
1919 ];
1920 }
1921 if (this.board[ex][ey] != "") {
1922 mv.vanish.push(
1923 new PiPo({
1924 x: ex,
1925 y: ey,
1926 c: this.getColor(ex, ey),
1927 p: this.getPiece(ex, ey)
1928 })
1929 );
1930 if (this.options["cannibal"] && destColor != initColor) {
1931 const lastIdx = mv.vanish.length - 1; //think "Rifle+Cannibal"
1932 let trPiece = mv.vanish[lastIdx].p;
1933 if (this.isKing(sx, sy))
1934 trPiece = C.CannibalKingCode[trPiece];
1935 if (mv.appear.length >= 1)
1936 mv.appear[0].p = trPiece;
1937 else if (this.options["rifle"]) {
1938 mv.appear.unshift(
1939 new PiPo({
1940 x: sx,
1941 y: sy,
1942 c: initColor,
1943 p: trPiece
1944 })
1945 );
1946 mv.vanish.unshift(
1947 new PiPo({
1948 x: sx,
1949 y: sy,
1950 c: initColor,
1951 p: initPiece
1952 })
1953 );
1954 }
1955 }
1956 }
1957 return mv;
1958 }
1959
1960 // En-passant square, if any
1961 getEpSquare(moveOrSquare) {
1962 if (typeof moveOrSquare === "string") {
1963 const square = moveOrSquare;
1964 if (square == "-")
1965 return undefined;
1966 return C.SquareToCoords(square);
1967 }
1968 // Argument is a move:
1969 const move = moveOrSquare;
1970 const s = move.start,
1971 e = move.end;
1972 if (
1973 s.y == e.y &&
1974 Math.abs(s.x - e.x) == 2 &&
1975 // Next conditions for variants like Atomic or Rifle, Recycle...
1976 (
1977 move.appear.length > 0 &&
1978 this.getPieceType(0, 0, move.appear[0].p) == 'p'
1979 )
1980 &&
1981 (
1982 move.vanish.length > 0 &&
1983 this.getPieceType(0, 0, move.vanish[0].p) == 'p'
1984 )
1985 ) {
1986 return {
1987 x: (s.x + e.x) / 2,
1988 y: s.y
1989 };
1990 }
1991 return undefined; //default
1992 }
1993
1994 // Special case of en-passant captures: treated separately
1995 getEnpassantCaptures([x, y]) {
1996 const color = this.getColor(x, y);
1997 const shiftX = (color == 'w' ? -1 : 1);
1998 const oppCols = this.getOppCols(color);
1999 if (
2000 this.epSquare &&
2001 this.epSquare.x == x + shiftX && //NOTE: epSquare.x not on edge
2002 Math.abs(this.getY(this.epSquare.y - y)) == 1 &&
2003 // Doublemove (and Progressive?) guards:
2004 this.board[this.epSquare.x][this.epSquare.y] == "" &&
2005 oppCols.includes(this.getColor(x, this.epSquare.y))
2006 ) {
2007 const [epx, epy] = [this.epSquare.x, this.epSquare.y];
2008 this.board[epx][epy] = this.board[x][this.epSquare.y];
2009 let enpassantMove = this.getBasicMove([x, y], [epx, epy]);
2010 this.board[epx][epy] = "";
2011 const lastIdx = enpassantMove.vanish.length - 1; //think Rifle
2012 enpassantMove.vanish[lastIdx].x = x;
2013 return [enpassantMove];
2014 }
2015 return [];
2016 }
2017
2018 getCastleMoves([x, y], finalSquares, castleWith) {
2019 const c = this.getColor(x, y);
2020
2021 // Castling ?
2022 const oppCols = this.getOppCols(c);
2023 let moves = [];
2024 // King, then rook:
2025 finalSquares =
2026 finalSquares || [ [2, 3], [this.size.y - 2, this.size.y - 3] ];
2027 const castlingKing = this.getPiece(x, y);
2028 castlingCheck: for (
2029 let castleSide = 0;
2030 castleSide < 2;
2031 castleSide++ //large, then small
2032 ) {
2033 if (this.castleFlags[c][castleSide] >= this.size.y)
2034 continue;
2035 // If this code is reached, rook and king are on initial position
2036
2037 // NOTE: in some variants this is not a rook
2038 const rookPos = this.castleFlags[c][castleSide];
2039 const castlingPiece = this.getPiece(x, rookPos);
2040 if (
2041 this.board[x][rookPos] == "" ||
2042 this.getColor(x, rookPos) != c ||
2043 (castleWith && !castleWith.includes(castlingPiece))
2044 ) {
2045 // Rook is not here, or changed color (see Benedict)
2046 continue;
2047 }
2048 // Nothing on the path of the king ? (and no checks)
2049 const finDist = finalSquares[castleSide][0] - y;
2050 let step = finDist / Math.max(1, Math.abs(finDist));
2051 let i = y;
2052 do {
2053 if (
2054 // NOTE: next weird test because underCheck() verification
2055 // will be executed in filterValid() later.
2056 (
2057 i != finalSquares[castleSide][0] &&
2058 this.underCheck([[x, i]], oppCols)
2059 )
2060 ||
2061 (
2062 this.board[x][i] != "" &&
2063 // NOTE: next check is enough, because of chessboard constraints
2064 (this.getColor(x, i) != c || ![rookPos, y].includes(i))
2065 )
2066 ) {
2067 continue castlingCheck;
2068 }
2069 i += step;
2070 } while (i != finalSquares[castleSide][0]);
2071 // Nothing on the path to the rook?
2072 step = (castleSide == 0 ? -1 : 1);
2073 for (i = y + step; i != rookPos; i += step) {
2074 if (this.board[x][i] != "")
2075 continue castlingCheck;
2076 }
2077
2078 // Nothing on final squares, except maybe king and castling rook?
2079 for (i = 0; i < 2; i++) {
2080 if (
2081 finalSquares[castleSide][i] != rookPos &&
2082 this.board[x][finalSquares[castleSide][i]] != "" &&
2083 (
2084 finalSquares[castleSide][i] != y ||
2085 this.getColor(x, finalSquares[castleSide][i]) != c
2086 )
2087 ) {
2088 continue castlingCheck;
2089 }
2090 }
2091
2092 // If this code is reached, castle is potentially valid
2093 moves.push(
2094 new Move({
2095 appear: [
2096 new PiPo({
2097 x: x,
2098 y: finalSquares[castleSide][0],
2099 p: castlingKing,
2100 c: c
2101 }),
2102 new PiPo({
2103 x: x,
2104 y: finalSquares[castleSide][1],
2105 p: castlingPiece,
2106 c: c
2107 })
2108 ],
2109 vanish: [
2110 // King might be initially disguised (Titan...)
2111 new PiPo({ x: x, y: y, p: castlingKing, c: c }),
2112 new PiPo({ x: x, y: rookPos, p: castlingPiece, c: c })
2113 ],
2114 end:
2115 Math.abs(y - rookPos) <= 2
2116 ? {x: x, y: rookPos}
2117 : {x: x, y: y + 2 * (castleSide == 0 ? -1 : 1)}
2118 })
2119 );
2120 }
2121
2122 return moves;
2123 }
2124
2125 ////////////////////
2126 // MOVES VALIDATION
2127
2128 // Is piece (or square) at given position attacked by "oppCol(s)" ?
2129 underAttack([x, y], oppCols) {
2130 // An empty square is considered as king,
2131 // since it's used only in getCastleMoves (TODO?)
2132 const king = this.board[x][y] == "" || this.isKing(x, y);
2133 return (
2134 (
2135 (!this.options["zen"] || king) &&
2136 this.findCapturesOn(
2137 [x, y],
2138 {
2139 byCol: oppCols,
2140 one: true
2141 }
2142 )
2143 )
2144 ||
2145 (
2146 (!!this.options["zen"] && !king) &&
2147 this.findDestSquares(
2148 [x, y],
2149 {
2150 attackOnly: true,
2151 one: true
2152 },
2153 ([i1, j1], [i2, j2]) => oppCols.includes(this.getColor(i2, j2))
2154 )
2155 )
2156 );
2157 }
2158
2159 // Argument is (very generally) an array of squares (= arrays)
2160 underCheck(square_s, oppCols) {
2161 if (this.options["taking"] || this.options["dark"])
2162 return false;
2163 return square_s.some(sq => this.underAttack(sq, oppCols));
2164 }
2165
2166 // Scan board for king(s)
2167 searchKingPos(color) {
2168 let res = [];
2169 for (let i=0; i < this.size.x; i++) {
2170 for (let j=0; j < this.size.y; j++) {
2171 if (this.getColor(i, j) == color && this.isKing(i, j))
2172 res.push([i, j]);
2173 }
2174 }
2175 return res;
2176 }
2177
2178 // cb: callback returning a boolean (false if king missing)
2179 trackKingWrap(move, kingPos, cb) {
2180 if (move.appear.length == 0 && move.vanish.length == 0)
2181 return true;
2182 const color =
2183 (move.vanish.length > 0 ? move.vanish[0].c : move.appear[0].c);
2184 let newKingPP = null,
2185 sqIdx = 0,
2186 res = true; //a priori valid
2187 const oldKingPP =
2188 move.vanish.find(v => this.isKing(0, 0, v.p) && v.c == color);
2189 if (oldKingPP) {
2190 // Search king in appear array:
2191 newKingPP =
2192 move.appear.find(a => this.isKing(0, 0, a.p) && a.c == color);
2193 if (newKingPP) {
2194 sqIdx = kingPos.findIndex(kp =>
2195 kp[0] == oldKingPP.x && kp[1] == oldKingPP.y);
2196 kingPos[sqIdx] = [newKingPP.x, newKingPP.y];
2197 }
2198 else
2199 res = false; //king vanished
2200 }
2201 res &&= cb(kingPos);
2202 if (oldKingPP && newKingPP)
2203 kingPos[sqIdx] = [oldKingPP.x, oldKingPP.y];
2204 return res;
2205 }
2206
2207 // 'color' arg because some variants (e.g. Refusal) check opponent moves
2208 filterValid(moves, color) {
2209 if (!color)
2210 color = this.turn;
2211 const oppCols = this.getOppCols(color);
2212 let kingPos = this.searchKingPos(color);
2213 return moves.filter(m => {
2214 this.playOnBoard(m);
2215 const res = this.trackKingWrap(m, kingPos, (kp) => {
2216 return !this.underCheck(kp, oppCols);
2217 });
2218 this.undoOnBoard(m);
2219 return res;
2220 });
2221 }
2222
2223 /////////////////
2224 // MOVES PLAYING
2225
2226 // Apply a move on board
2227 playOnBoard(move) {
2228 for (let psq of move.vanish)
2229 this.board[psq.x][psq.y] = "";
2230 for (let psq of move.appear)
2231 this.board[psq.x][psq.y] = psq.c + psq.p;
2232 }
2233 // Un-apply the played move
2234 undoOnBoard(move) {
2235 for (let psq of move.appear)
2236 this.board[psq.x][psq.y] = "";
2237 for (let psq of move.vanish)
2238 this.board[psq.x][psq.y] = psq.c + psq.p;
2239 }
2240
2241 updateCastleFlags(move) {
2242 // Update castling flags if start or arrive from/at rook/king locations
2243 move.appear.concat(move.vanish).forEach(psq => {
2244 if (this.isKing(0, 0, psq.p))
2245 this.castleFlags[psq.c] = [this.size.y, this.size.y];
2246 // NOTE: not "else if" because king can capture enemy rook...
2247 let c = "";
2248 if (psq.x == 0)
2249 c = "b";
2250 else if (psq.x == this.size.x - 1)
2251 c = "w";
2252 if (c != "") {
2253 const fidx = this.castleFlags[c].findIndex(f => f == psq.y);
2254 if (fidx >= 0)
2255 this.castleFlags[c][fidx] = this.size.y;
2256 }
2257 });
2258 }
2259
2260 prePlay(move) {
2261 if (
2262 this.hasCastle &&
2263 // If flags already off, no need to re-check:
2264 Object.values(this.castleFlags).some(cvals =>
2265 cvals.some(val => val < this.size.y))
2266 ) {
2267 this.updateCastleFlags(move);
2268 }
2269 if (this.options["crazyhouse"]) {
2270 move.vanish.forEach(v => {
2271 const square = C.CoordsToSquare({x: v.x, y: v.y});
2272 if (this.ispawn[square])
2273 delete this.ispawn[square];
2274 });
2275 if (move.appear.length > 0 && move.vanish.length > 0) {
2276 // Assumption: something is moving
2277 const initSquare = C.CoordsToSquare(move.start);
2278 const destSquare = C.CoordsToSquare(move.end);
2279 if (
2280 this.ispawn[initSquare] ||
2281 (move.vanish[0].p == 'p' && move.appear[0].p != 'p')
2282 ) {
2283 this.ispawn[destSquare] = true;
2284 }
2285 else if (
2286 this.ispawn[destSquare] &&
2287 this.getColor(move.end.x, move.end.y) != move.vanish[0].c
2288 ) {
2289 move.vanish[1].p = 'p';
2290 delete this.ispawn[destSquare];
2291 }
2292 }
2293 }
2294 const minSize = Math.min(move.appear.length, move.vanish.length);
2295 if (
2296 this.hasReserve &&
2297 // Warning; atomic pawn removal isn't a capture
2298 (!this.options["atomic"] || !this.rempawn || this.movesCount >= 1)
2299 ) {
2300 const color = this.turn;
2301 for (let i=minSize; i<move.appear.length; i++) {
2302 // Something appears = dropped on board (some exceptions, Chakart...)
2303 if (move.appear[i].c == color) {
2304 const piece = move.appear[i].p;
2305 this.updateReserve(color, piece, this.reserve[color][piece] - 1);
2306 }
2307 }
2308 for (let i=minSize; i<move.vanish.length; i++) {
2309 // Something vanish: add to reserve except if recycle & opponent
2310 if (
2311 this.options["crazyhouse"] ||
2312 (this.options["recycle"] && move.vanish[i].c == color)
2313 ) {
2314 const piece = move.vanish[i].p;
2315 this.updateReserve(color, piece, this.reserve[color][piece] + 1);
2316 }
2317 }
2318 }
2319 }
2320
2321 play(move) {
2322 this.prePlay(move);
2323 if (this.hasEnpassant)
2324 this.epSquare = this.getEpSquare(move);
2325 this.playOnBoard(move);
2326 this.postPlay(move);
2327 }
2328
2329 postPlay(move) {
2330 if (this.options["dark"])
2331 this.updateEnlightened();
2332 if (this.options["teleport"]) {
2333 if (
2334 this.subTurnTeleport == 1 &&
2335 move.vanish.length > move.appear.length &&
2336 move.vanish[1].c == this.turn
2337 ) {
2338 const v = move.vanish[move.vanish.length - 1];
2339 this.captured = {x: v.x, y: v.y, c: v.c, p: v.p};
2340 this.subTurnTeleport = 2;
2341 return;
2342 }
2343 this.subTurnTeleport = 1;
2344 this.captured = null;
2345 }
2346 this.tryChangeTurn(move);
2347 }
2348
2349 tryChangeTurn(move) {
2350 if (this.isLastMove(move)) {
2351 this.turn = C.GetOppTurn(this.turn);
2352 this.movesCount++;
2353 this.subTurn = 1;
2354 }
2355 else if (!move.next)
2356 this.subTurn++;
2357 }
2358
2359 isLastMove(move) {
2360 if (move.next)
2361 return false;
2362 const color = this.turn;
2363 const oppKingPos = this.searchKingPos(C.GetOppTurn(color));
2364 if (oppKingPos.length == 0 || this.underCheck(oppKingPos, [color]))
2365 return true;
2366 return (
2367 (
2368 !this.options["balance"] ||
2369 ![1, 2].includes(this.movesCount) ||
2370 this.subTurn == 2
2371 )
2372 &&
2373 (
2374 !this.options["doublemove"] ||
2375 this.movesCount == 0 ||
2376 this.subTurn == 2
2377 )
2378 &&
2379 (
2380 !this.options["progressive"] ||
2381 this.subTurn == this.movesCount + 1
2382 )
2383 );
2384 }
2385
2386 // "Stop at the first move found"
2387 atLeastOneMove(color) {
2388 for (let i = 0; i < this.size.x; i++) {
2389 for (let j = 0; j < this.size.y; j++) {
2390 if (this.board[i][j] != "" && this.getColor(i, j) == color) {
2391 // NOTE: in fact searching for all potential moves from i,j.
2392 // I don't believe this is an issue, for now at least.
2393 const moves = this.getPotentialMovesFrom([i, j], color);
2394 if (moves.some(m => this.filterValid([m]).length >= 1))
2395 return true;
2396 }
2397 }
2398 }
2399 if (this.hasReserve && this.reserve[color]) {
2400 for (let p of Object.keys(this.reserve[color])) {
2401 const moves = this.getDropMovesFrom([color, p]);
2402 if (moves.some(m => this.filterValid([m]).length >= 1))
2403 return true;
2404 }
2405 }
2406 return false;
2407 }
2408
2409 // What is the score ? (Interesting if game is over)
2410 getCurrentScore(move_s) {
2411 const move = move_s[move_s.length - 1];
2412 // Shortcut in case the score was computed before:
2413 if (move.result)
2414 return move.result;
2415 const oppTurn = C.GetOppTurn(this.turn);
2416 const kingPos = {
2417 w: this.searchKingPos('w'),
2418 b: this.searchKingPos('b')
2419 };
2420 if (kingPos[this.turn].length == 0 && kingPos[oppTurn].length == 0)
2421 return "1/2";
2422 if (kingPos[this.turn].length == 0)
2423 return (this.turn == "w" ? "0-1" : "1-0");
2424 if (kingPos[oppTurn].length == 0)
2425 return (this.turn == "w" ? "1-0" : "0-1");
2426 if (this.atLeastOneMove(this.turn))
2427 return "*";
2428 // No valid move: stalemate or checkmate?
2429 if (!this.underCheck(kingPos[this.turn], this.getOppCols(this.turn)))
2430 return "1/2";
2431 // OK, checkmate
2432 return (this.turn == "w" ? "0-1" : "1-0");
2433 }
2434
2435 playVisual(move, r) {
2436 move.vanish.forEach(v => {
2437 if (this.g_pieces[v.x][v.y]) //can be null (e.g. Apocalypse)
2438 this.g_pieces[v.x][v.y].remove();
2439 this.g_pieces[v.x][v.y] = null;
2440 });
2441 let chessboard =
2442 document.getElementById(this.containerId).querySelector(".chessboard");
2443 if (!r)
2444 r = chessboard.getBoundingClientRect();
2445 const pieceWidth = this.getPieceWidth(r.width);
2446 move.appear.forEach(a => {
2447 this.g_pieces[a.x][a.y] = document.createElement("piece");
2448 C.AddClass_es(this.g_pieces[a.x][a.y],
2449 this.pieces(a.c, a.x, a.y)[a.p]["class"]);
2450 this.g_pieces[a.x][a.y].classList.add(V.GetColorClass(a.c));
2451 this.g_pieces[a.x][a.y].style.width = pieceWidth + "px";
2452 this.g_pieces[a.x][a.y].style.height = pieceWidth + "px";
2453 const [ip, jp] = this.getPixelPosition(a.x, a.y, r);
2454 // Translate coordinates to use chessboard as reference:
2455 this.g_pieces[a.x][a.y].style.transform =
2456 `translate(${ip - r.x}px,${jp - r.y}px)`;
2457 if (this.enlightened && !this.enlightened[a.x][a.y])
2458 this.g_pieces[a.x][a.y].classList.add("hidden");
2459 chessboard.appendChild(this.g_pieces[a.x][a.y]);
2460 });
2461 if (this.options["dark"])
2462 this.graphUpdateEnlightened();
2463 }
2464
2465 // TODO: send stack receive stack, or allow incremental? (good/bad points)
2466 buildMoveStack(move, r) {
2467 this.moveStack.push(move);
2468 this.computeNextMove(move);
2469 const then = () => {
2470 const newTurn = this.turn;
2471 if (this.moveStack.length == 1 && !this.hideMoves)
2472 this.playVisual(move, r);
2473 if (move.next) {
2474 this.gameState = {
2475 fen: this.getFen(),
2476 board: JSON.parse(JSON.stringify(this.board)) //easier
2477 };
2478 this.buildMoveStack(move.next, r);
2479 }
2480 else {
2481 if (this.moveStack.length == 1) {
2482 // Usual case (one normal move)
2483 this.afterPlay(this.moveStack, newTurn, {send: true, res: true});
2484 this.moveStack = [];
2485 }
2486 else {
2487 this.afterPlay(this.moveStack, newTurn, {send: true, res: false});
2488 this.re_initFromFen(this.gameState.fen, this.gameState.board);
2489 this.playReceivedMove(this.moveStack.slice(1), () => {
2490 this.afterPlay(this.moveStack, newTurn, {send: false, res: true});
2491 this.moveStack = [];
2492 });
2493 }
2494 }
2495 };
2496 // If hiding moves, then they are revealed in play() with callback
2497 this.play(move, this.hideMoves ? then : null);
2498 if (!this.hideMoves)
2499 then();
2500 }
2501
2502 // Implemented in variants using (automatic) moveStack
2503 computeNextMove(move) {}
2504
2505 animateMoving(start, end, drag, segments, cb) {
2506 let initPiece = this.getDomPiece(start.x, start.y);
2507 if (!initPiece) { //TODO: shouldn't occur!
2508 cb();
2509 return;
2510 }
2511 // NOTE: cloning often not required, but light enough, and simpler
2512 let movingPiece = initPiece.cloneNode();
2513 initPiece.style.opacity = "0";
2514 let container =
2515 document.getElementById(this.containerId)
2516 const r = container.querySelector(".chessboard").getBoundingClientRect();
2517 if (typeof start.x == "string") {
2518 // Need to bound width/height (was 100% for reserve pieces)
2519 const pieceWidth = this.getPieceWidth(r.width);
2520 movingPiece.style.width = pieceWidth + "px";
2521 movingPiece.style.height = pieceWidth + "px";
2522 }
2523 const maxDist = this.getMaxDistance(r);
2524 const apparentColor = this.getColor(start.x, start.y);
2525 const pieces = this.pieces(apparentColor, start.x, start.y);
2526 if (drag) {
2527 const startCode = this.getPiece(start.x, start.y);
2528 C.RemoveClass_es(movingPiece, pieces[startCode]["class"]);
2529 C.AddClass_es(movingPiece, pieces[drag.p]["class"]);
2530 if (apparentColor != drag.c) {
2531 movingPiece.classList.remove(V.GetColorClass(apparentColor));
2532 movingPiece.classList.add(V.GetColorClass(drag.c));
2533 }
2534 }
2535 container.appendChild(movingPiece);
2536 const animateSegment = (index, cb) => {
2537 // NOTE: move.drag could be generalized per-segment (usage?)
2538 const [i1, j1] = segments[index][0];
2539 const [i2, j2] = segments[index][1];
2540 const dep = this.getPixelPosition(i1, j1, r);
2541 const arr = this.getPixelPosition(i2, j2, r);
2542 movingPiece.style.transitionDuration = "0s";
2543 movingPiece.style.transform = `translate(${dep[0]}px, ${dep[1]}px)`;
2544 const distance =
2545 Math.sqrt((arr[0] - dep[0]) ** 2 + (arr[1] - dep[1]) ** 2);
2546 const duration = 0.2 + (distance / maxDist) * 0.3;
2547 // TODO: unclear why we need this new delay below:
2548 setTimeout(() => {
2549 movingPiece.style.transitionDuration = duration + "s";
2550 // movingPiece is child of container: no need to adjust coordinates
2551 movingPiece.style.transform = `translate(${arr[0]}px, ${arr[1]}px)`;
2552 setTimeout(cb, duration * 1000);
2553 }, 50);
2554 };
2555 let index = 0;
2556 const animateSegmentCallback = () => {
2557 if (index < segments.length)
2558 animateSegment(index++, animateSegmentCallback);
2559 else {
2560 movingPiece.remove();
2561 initPiece.style.opacity = "1";
2562 cb();
2563 }
2564 };
2565 animateSegmentCallback();
2566 }
2567
2568 // Input array of objects with at least fields x,y (e.g. PiPo)
2569 animateFading(arr, cb) {
2570 const animLength = 350; //TODO: 350ms? More? Less?
2571 arr.forEach(v => {
2572 let fadingPiece = this.getDomPiece(v.x, v.y);
2573 fadingPiece.style.transitionDuration = (animLength / 1000) + "s";
2574 fadingPiece.style.opacity = "0";
2575 });
2576 setTimeout(cb, animLength);
2577 }
2578
2579 animate(move, callback) {
2580 if (this.noAnimate || move.noAnimate) {
2581 callback();
2582 return;
2583 }
2584 let segments = move.segments;
2585 if (!segments)
2586 segments = [ [[move.start.x, move.start.y], [move.end.x, move.end.y]] ];
2587 let targetObj = new TargetObj(callback);
2588 if (move.start.x != move.end.x || move.start.y != move.end.y) {
2589 targetObj.target++;
2590 this.animateMoving(move.start, move.end, move.drag, segments,
2591 () => targetObj.increment());
2592 }
2593 if (move.vanish.length > move.appear.length) {
2594 const arr = move.vanish.slice(move.appear.length)
2595 // Ignore disappearing pieces hidden by some appearing ones:
2596 .filter(v => move.appear.every(a => a.x != v.x || a.y != v.y));
2597 if (arr.length > 0) {
2598 targetObj.target++;
2599 this.animateFading(arr, () => targetObj.increment());
2600 }
2601 }
2602 targetObj.target +=
2603 this.tryAnimateCastle(move, () => targetObj.increment());
2604 targetObj.target +=
2605 this.customAnimate(move, segments, () => targetObj.increment());
2606 if (targetObj.target == 0)
2607 callback();
2608 }
2609
2610 tryAnimateCastle(move, cb) {
2611 if (
2612 this.hasCastle &&
2613 move.vanish.length == 2 &&
2614 move.appear.length == 2 &&
2615 this.isKing(0, 0, move.vanish[0].p) &&
2616 this.isKing(0, 0, move.appear[0].p)
2617 ) {
2618 const start = {x: move.vanish[1].x, y: move.vanish[1].y},
2619 end = {x: move.appear[1].x, y: move.appear[1].y};
2620 const segments = [ [[start.x, start.y], [end.x, end.y]] ];
2621 this.animateMoving(start, end, null, segments, cb);
2622 return 1;
2623 }
2624 return 0;
2625 }
2626
2627 // Potential other animations (e.g. for Suction variant)
2628 customAnimate(move, segments, cb) {
2629 return 0; //nb of targets
2630 }
2631
2632 launchAnimation(moves, container, callback) {
2633 if (this.hideMoves) {
2634 for (let i=0; i<moves.length; i++)
2635 // If hiding moves, they are revealed into play():
2636 this.play(moves[i], i == moves.length - 1 ? callback : () => {});
2637 return;
2638 }
2639 const r = container.querySelector(".chessboard").getBoundingClientRect();
2640 const animateRec = i => {
2641 this.animate(moves[i], () => {
2642 this.play(moves[i]);
2643 this.playVisual(moves[i], r);
2644 if (i < moves.length - 1)
2645 setTimeout(() => animateRec(i+1), 300);
2646 else
2647 callback();
2648 });
2649 };
2650 animateRec(0);
2651 }
2652
2653 playReceivedMove(moves, callback) {
2654 // Delay if user wasn't focused:
2655 const checkDisplayThenAnimate = (delay) => {
2656 if (container.style.display == "none") {
2657 alert("New move! Let's go back to game...");
2658 document.getElementById("gameInfos").style.display = "none";
2659 container.style.display = "block";
2660 setTimeout(
2661 () => this.launchAnimation(moves, container, callback),
2662 700
2663 );
2664 }
2665 else {
2666 setTimeout(
2667 () => this.launchAnimation(moves, container, callback),
2668 delay || 0
2669 );
2670 }
2671 };
2672 let container = document.getElementById(this.containerId);
2673 if (document.hidden) {
2674 document.onvisibilitychange = () => {
2675 // TODO here: page reload ?! (some issues if tab changed...)
2676 document.onvisibilitychange = undefined;
2677 checkDisplayThenAnimate(700);
2678 };
2679 }
2680 else
2681 checkDisplayThenAnimate();
2682 }
2683
2684 };