Commit | Line | Data |
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92342261 BA |
1 | // (Orthodox) Chess rules are defined in ChessRules class. |
2 | // Variants generally inherit from it, and modify some parts. | |
3 | ||
e2732923 | 4 | import { ArrayFun } from "@/utils/array"; |
0c3fe8a6 | 5 | import { randInt, shuffle } from "@/utils/alea"; |
e2732923 | 6 | |
910d631b | 7 | // class "PiPo": Piece + Position |
6808d7a1 | 8 | export const PiPo = class PiPo { |
1c9f093d | 9 | // o: {piece[p], color[c], posX[x], posY[y]} |
6808d7a1 | 10 | constructor(o) { |
1c9f093d BA |
11 | this.p = o.p; |
12 | this.c = o.c; | |
13 | this.x = o.x; | |
14 | this.y = o.y; | |
15 | } | |
6808d7a1 | 16 | }; |
1d184b4c | 17 | |
6808d7a1 | 18 | export const Move = class Move { |
1c9f093d BA |
19 | // o: {appear, vanish, [start,] [end,]} |
20 | // appear,vanish = arrays of PiPo | |
21 | // start,end = coordinates to apply to trigger move visually (think castle) | |
6808d7a1 | 22 | constructor(o) { |
1c9f093d BA |
23 | this.appear = o.appear; |
24 | this.vanish = o.vanish; | |
2da551a3 BA |
25 | this.start = o.start || { x: o.vanish[0].x, y: o.vanish[0].y }; |
26 | this.end = o.end || { x: o.appear[0].x, y: o.appear[0].y }; | |
1c9f093d | 27 | } |
6808d7a1 | 28 | }; |
1d184b4c | 29 | |
2c5d7b20 BA |
30 | // NOTE: x coords = top to bottom; y = left to right |
31 | // (from white player perspective) | |
6808d7a1 | 32 | export const ChessRules = class ChessRules { |
7e8a7ea1 | 33 | |
1c9f093d BA |
34 | ////////////// |
35 | // MISC UTILS | |
36 | ||
eb2d61de BA |
37 | static get Options() { |
38 | return { | |
39 | select: [ | |
40 | { | |
41 | label: "Randomness", | |
42 | variable: "randomness", | |
4313762d | 43 | defaut: 0, |
eb2d61de BA |
44 | options: [ |
45 | { label: "Deterministic", value: 0 }, | |
46 | { label: "Symmetric random", value: 1 }, | |
47 | { label: "Asymmetric random", value: 2 } | |
48 | ] | |
49 | } | |
50 | ], | |
51 | check: [] | |
52 | }; | |
53 | } | |
54 | ||
55 | static AbbreviateOptions(opts) { | |
56 | return ""; | |
57 | // Randomness is a special option: (TODO?) | |
58 | //return "R" + opts.randomness; | |
59 | } | |
60 | ||
4313762d BA |
61 | static IsValidOptions(opts) { |
62 | return true; | |
63 | } | |
64 | ||
20620465 | 65 | // Some variants don't have flags: |
6808d7a1 BA |
66 | static get HasFlags() { |
67 | return true; | |
20620465 | 68 | } |
1c9f093d | 69 | |
3a2a7b5f BA |
70 | // Or castle |
71 | static get HasCastle() { | |
72 | return V.HasFlags; | |
73 | } | |
74 | ||
32f6285e BA |
75 | // Pawns specifications |
76 | static get PawnSpecs() { | |
77 | return { | |
78 | directions: { 'w': -1, 'b': 1 }, | |
472c0c4f | 79 | initShift: { w: 1, b: 1 }, |
32f6285e | 80 | twoSquares: true, |
472c0c4f | 81 | threeSquares: false, |
32f6285e BA |
82 | promotions: [V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN], |
83 | canCapture: true, | |
84 | captureBackward: false, | |
85 | bidirectional: false | |
86 | }; | |
87 | } | |
88 | ||
89 | // En-passant captures need a stack of squares: | |
6808d7a1 BA |
90 | static get HasEnpassant() { |
91 | return true; | |
20620465 BA |
92 | } |
93 | ||
94 | // Some variants cannot have analyse mode | |
8477e53d | 95 | static get CanAnalyze() { |
20620465 BA |
96 | return true; |
97 | } | |
933fd1f9 BA |
98 | // Patch: issues with javascript OOP, objects can't access static fields. |
99 | get canAnalyze() { | |
100 | return V.CanAnalyze; | |
101 | } | |
20620465 BA |
102 | |
103 | // Some variants show incomplete information, | |
104 | // and thus show only a partial moves list or no list at all. | |
105 | static get ShowMoves() { | |
106 | return "all"; | |
107 | } | |
933fd1f9 BA |
108 | get showMoves() { |
109 | return V.ShowMoves; | |
110 | } | |
1c9f093d | 111 | |
00eef1ca BA |
112 | // Sometimes moves must remain hidden until game ends |
113 | static get SomeHiddenMoves() { | |
114 | return false; | |
115 | } | |
116 | get someHiddenMoves() { | |
117 | return V.SomeHiddenMoves; | |
118 | } | |
119 | ||
ad030c7d BA |
120 | // Generally true, unless the variant includes random effects |
121 | static get CorrConfirm() { | |
122 | return true; | |
123 | } | |
124 | ||
5246b49d BA |
125 | // Used for Monochrome variant (TODO: harmonize: !canFlip ==> showFirstTurn) |
126 | get showFirstTurn() { | |
127 | return false; | |
128 | } | |
129 | ||
71ef1664 BA |
130 | // Some variants always show the same orientation |
131 | static get CanFlip() { | |
132 | return true; | |
133 | } | |
134 | get canFlip() { | |
135 | return V.CanFlip; | |
136 | } | |
137 | ||
10cceb25 | 138 | // NOTE: these will disappear once each variant has its dedicated SVG board. |
107dc1bd BA |
139 | // For (generally old) variants without checkered board |
140 | static get Monochrome() { | |
141 | return false; | |
142 | } | |
173f11dc | 143 | // Some games are drawn unusually (bottom right corner is black) |
157a72c8 BA |
144 | static get DarkBottomRight() { |
145 | return false; | |
146 | } | |
107dc1bd BA |
147 | // Some variants require lines drawing |
148 | static get Lines() { | |
149 | if (V.Monochrome) { | |
150 | let lines = []; | |
151 | // Draw all inter-squares lines | |
152 | for (let i = 0; i <= V.size.x; i++) | |
153 | lines.push([[i, 0], [i, V.size.y]]); | |
154 | for (let j = 0; j <= V.size.y; j++) | |
155 | lines.push([[0, j], [V.size.x, j]]); | |
156 | return lines; | |
157 | } | |
158 | return null; | |
159 | } | |
160 | ||
9a1e3abe BA |
161 | // In some variants, the player who repeat a position loses |
162 | static get LoseOnRepetition() { | |
d2af3400 BA |
163 | return false; |
164 | } | |
f0a812b7 BA |
165 | // And in some others (Iceage), repetitions should be ignored: |
166 | static get IgnoreRepetition() { | |
167 | return false; | |
168 | } | |
809ab1a8 BA |
169 | loseOnRepetition() { |
170 | // In some variants, result depends on the position: | |
171 | return V.LoseOnRepetition; | |
172 | } | |
d2af3400 BA |
173 | |
174 | // At some stages, some games could wait clicks only: | |
175 | onlyClick() { | |
9a1e3abe BA |
176 | return false; |
177 | } | |
178 | ||
61656127 BA |
179 | // Some variants use click infos: |
180 | doClick() { | |
181 | return null; | |
182 | } | |
183 | ||
90df90bc BA |
184 | // Some variants may need to highlight squares on hover (Hamilton, Weiqi...) |
185 | hoverHighlight() { | |
186 | return false; | |
187 | } | |
188 | ||
14edde72 BA |
189 | static get IMAGE_EXTENSION() { |
190 | // All pieces should be in the SVG format | |
191 | return ".svg"; | |
192 | } | |
193 | ||
1c9f093d | 194 | // Turn "wb" into "B" (for FEN) |
6808d7a1 BA |
195 | static board2fen(b) { |
196 | return b[0] == "w" ? b[1].toUpperCase() : b[1]; | |
1c9f093d BA |
197 | } |
198 | ||
199 | // Turn "p" into "bp" (for board) | |
6808d7a1 | 200 | static fen2board(f) { |
6cc34165 | 201 | return f.charCodeAt(0) <= 90 ? "w" + f.toLowerCase() : "b" + f; |
1c9f093d BA |
202 | } |
203 | ||
68e19a44 | 204 | // Check if FEN describes a board situation correctly |
6808d7a1 | 205 | static IsGoodFen(fen) { |
1c9f093d BA |
206 | const fenParsed = V.ParseFen(fen); |
207 | // 1) Check position | |
6808d7a1 | 208 | if (!V.IsGoodPosition(fenParsed.position)) return false; |
1c9f093d | 209 | // 2) Check turn |
6808d7a1 | 210 | if (!fenParsed.turn || !V.IsGoodTurn(fenParsed.turn)) return false; |
1c9f093d | 211 | // 3) Check moves count |
e50a8025 | 212 | if (!fenParsed.movesCount || !(parseInt(fenParsed.movesCount, 10) >= 0)) |
1c9f093d BA |
213 | return false; |
214 | // 4) Check flags | |
215 | if (V.HasFlags && (!fenParsed.flags || !V.IsGoodFlags(fenParsed.flags))) | |
216 | return false; | |
217 | // 5) Check enpassant | |
6808d7a1 BA |
218 | if ( |
219 | V.HasEnpassant && | |
220 | (!fenParsed.enpassant || !V.IsGoodEnpassant(fenParsed.enpassant)) | |
221 | ) { | |
1c9f093d BA |
222 | return false; |
223 | } | |
224 | return true; | |
225 | } | |
226 | ||
227 | // Is position part of the FEN a priori correct? | |
6808d7a1 BA |
228 | static IsGoodPosition(position) { |
229 | if (position.length == 0) return false; | |
1c9f093d | 230 | const rows = position.split("/"); |
6808d7a1 | 231 | if (rows.length != V.size.x) return false; |
6f2f9437 | 232 | let kings = { "k": 0, "K": 0 }; |
6808d7a1 | 233 | for (let row of rows) { |
1c9f093d | 234 | let sumElts = 0; |
6808d7a1 | 235 | for (let i = 0; i < row.length; i++) { |
6f2f9437 | 236 | if (['K','k'].includes(row[i])) kings[row[i]]++; |
6808d7a1 BA |
237 | if (V.PIECES.includes(row[i].toLowerCase())) sumElts++; |
238 | else { | |
e50a8025 | 239 | const num = parseInt(row[i], 10); |
173f11dc | 240 | if (isNaN(num) || num <= 0) return false; |
1c9f093d BA |
241 | sumElts += num; |
242 | } | |
243 | } | |
6808d7a1 | 244 | if (sumElts != V.size.y) return false; |
1c9f093d | 245 | } |
6f2f9437 BA |
246 | // Both kings should be on board. Exactly one per color. |
247 | if (Object.values(kings).some(v => v != 1)) return false; | |
1c9f093d BA |
248 | return true; |
249 | } | |
250 | ||
251 | // For FEN checking | |
6808d7a1 BA |
252 | static IsGoodTurn(turn) { |
253 | return ["w", "b"].includes(turn); | |
1c9f093d BA |
254 | } |
255 | ||
256 | // For FEN checking | |
6808d7a1 | 257 | static IsGoodFlags(flags) { |
3a2a7b5f BA |
258 | // NOTE: a little too permissive to work with more variants |
259 | return !!flags.match(/^[a-z]{4,4}$/); | |
1c9f093d BA |
260 | } |
261 | ||
472c0c4f | 262 | // NOTE: not with regexp to adapt to different board sizes. (TODO?) |
6808d7a1 BA |
263 | static IsGoodEnpassant(enpassant) { |
264 | if (enpassant != "-") { | |
265 | const ep = V.SquareToCoords(enpassant); | |
266 | if (isNaN(ep.x) || !V.OnBoard(ep)) return false; | |
1c9f093d BA |
267 | } |
268 | return true; | |
269 | } | |
270 | ||
271 | // 3 --> d (column number to letter) | |
6808d7a1 | 272 | static CoordToColumn(colnum) { |
1c9f093d BA |
273 | return String.fromCharCode(97 + colnum); |
274 | } | |
275 | ||
276 | // d --> 3 (column letter to number) | |
6808d7a1 | 277 | static ColumnToCoord(column) { |
1c9f093d BA |
278 | return column.charCodeAt(0) - 97; |
279 | } | |
280 | ||
281 | // a4 --> {x:3,y:0} | |
6808d7a1 | 282 | static SquareToCoords(sq) { |
1c9f093d BA |
283 | return { |
284 | // NOTE: column is always one char => max 26 columns | |
285 | // row is counted from black side => subtraction | |
e50a8025 | 286 | x: V.size.x - parseInt(sq.substr(1), 10), |
1c9f093d BA |
287 | y: sq[0].charCodeAt() - 97 |
288 | }; | |
289 | } | |
290 | ||
291 | // {x:0,y:4} --> e8 | |
6808d7a1 | 292 | static CoordsToSquare(coords) { |
1c9f093d BA |
293 | return V.CoordToColumn(coords.y) + (V.size.x - coords.x); |
294 | } | |
295 | ||
305ede7e | 296 | // Path to pieces (standard ones in pieces/ folder) |
241bf8f2 | 297 | getPpath(b) { |
305ede7e | 298 | return b; |
241bf8f2 BA |
299 | } |
300 | ||
3a2a7b5f | 301 | // Path to promotion pieces (usually the same) |
c7550017 BA |
302 | getPPpath(m) { |
303 | return this.getPpath(m.appear[0].c + m.appear[0].p); | |
3a2a7b5f BA |
304 | } |
305 | ||
1c9f093d | 306 | // Aggregates flags into one object |
6808d7a1 | 307 | aggregateFlags() { |
1c9f093d BA |
308 | return this.castleFlags; |
309 | } | |
310 | ||
311 | // Reverse operation | |
6808d7a1 | 312 | disaggregateFlags(flags) { |
1c9f093d BA |
313 | this.castleFlags = flags; |
314 | } | |
315 | ||
316 | // En-passant square, if any | |
6808d7a1 | 317 | getEpSquare(moveOrSquare) { |
4a209313 | 318 | if (!moveOrSquare) return undefined; //TODO: necessary line?! |
6808d7a1 | 319 | if (typeof moveOrSquare === "string") { |
1c9f093d | 320 | const square = moveOrSquare; |
6808d7a1 | 321 | if (square == "-") return undefined; |
1c9f093d BA |
322 | return V.SquareToCoords(square); |
323 | } | |
324 | // Argument is a move: | |
325 | const move = moveOrSquare; | |
1c5bfdf2 BA |
326 | const s = move.start, |
327 | e = move.end; | |
6808d7a1 | 328 | if ( |
1c5bfdf2 | 329 | s.y == e.y && |
0d5335de BA |
330 | Math.abs(s.x - e.x) == 2 && |
331 | // Next conditions for variants like Atomic or Rifle, Recycle... | |
332 | (move.appear.length > 0 && move.appear[0].p == V.PAWN) && | |
333 | (move.vanish.length > 0 && move.vanish[0].p == V.PAWN) | |
6808d7a1 | 334 | ) { |
1c9f093d | 335 | return { |
1c5bfdf2 BA |
336 | x: (s.x + e.x) / 2, |
337 | y: s.y | |
1c9f093d BA |
338 | }; |
339 | } | |
340 | return undefined; //default | |
341 | } | |
342 | ||
343 | // Can thing on square1 take thing on square2 | |
6808d7a1 BA |
344 | canTake([x1, y1], [x2, y2]) { |
345 | return this.getColor(x1, y1) !== this.getColor(x2, y2); | |
1c9f093d BA |
346 | } |
347 | ||
348 | // Is (x,y) on the chessboard? | |
6808d7a1 BA |
349 | static OnBoard(x, y) { |
350 | return x >= 0 && x < V.size.x && y >= 0 && y < V.size.y; | |
1c9f093d BA |
351 | } |
352 | ||
353 | // Used in interface: 'side' arg == player color | |
6808d7a1 BA |
354 | canIplay(side, [x, y]) { |
355 | return this.turn == side && this.getColor(x, y) == side; | |
1c9f093d BA |
356 | } |
357 | ||
358 | // On which squares is color under check ? (for interface) | |
af34341d BA |
359 | getCheckSquares() { |
360 | const color = this.turn; | |
b0a0468a BA |
361 | return ( |
362 | this.underCheck(color) | |
2c5d7b20 BA |
363 | // kingPos must be duplicated, because it may change: |
364 | ? [JSON.parse(JSON.stringify(this.kingPos[color]))] | |
b0a0468a BA |
365 | : [] |
366 | ); | |
1c9f093d BA |
367 | } |
368 | ||
369 | ///////////// | |
370 | // FEN UTILS | |
371 | ||
7ba4a5bc | 372 | // Setup the initial random (asymmetric) position |
eb2d61de | 373 | static GenRandInitFen(options) { |
4313762d | 374 | if (!options.randomness || options.randomness == 0) |
7ba4a5bc | 375 | // Deterministic: |
3a2a7b5f | 376 | return "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w 0 ahah -"; |
7ba4a5bc | 377 | |
6808d7a1 | 378 | let pieces = { w: new Array(8), b: new Array(8) }; |
3a2a7b5f | 379 | let flags = ""; |
7ba4a5bc | 380 | // Shuffle pieces on first (and last rank if randomness == 2) |
6808d7a1 | 381 | for (let c of ["w", "b"]) { |
eb2d61de | 382 | if (c == 'b' && options.randomness == 1) { |
7ba4a5bc | 383 | pieces['b'] = pieces['w']; |
3a2a7b5f | 384 | flags += flags; |
7ba4a5bc BA |
385 | break; |
386 | } | |
387 | ||
1c9f093d BA |
388 | let positions = ArrayFun.range(8); |
389 | ||
390 | // Get random squares for bishops | |
656b1878 | 391 | let randIndex = 2 * randInt(4); |
1c9f093d BA |
392 | const bishop1Pos = positions[randIndex]; |
393 | // The second bishop must be on a square of different color | |
656b1878 | 394 | let randIndex_tmp = 2 * randInt(4) + 1; |
1c9f093d BA |
395 | const bishop2Pos = positions[randIndex_tmp]; |
396 | // Remove chosen squares | |
6808d7a1 BA |
397 | positions.splice(Math.max(randIndex, randIndex_tmp), 1); |
398 | positions.splice(Math.min(randIndex, randIndex_tmp), 1); | |
1c9f093d BA |
399 | |
400 | // Get random squares for knights | |
656b1878 | 401 | randIndex = randInt(6); |
1c9f093d BA |
402 | const knight1Pos = positions[randIndex]; |
403 | positions.splice(randIndex, 1); | |
656b1878 | 404 | randIndex = randInt(5); |
1c9f093d BA |
405 | const knight2Pos = positions[randIndex]; |
406 | positions.splice(randIndex, 1); | |
407 | ||
408 | // Get random square for queen | |
656b1878 | 409 | randIndex = randInt(4); |
1c9f093d BA |
410 | const queenPos = positions[randIndex]; |
411 | positions.splice(randIndex, 1); | |
412 | ||
413 | // Rooks and king positions are now fixed, | |
414 | // because of the ordering rook-king-rook | |
415 | const rook1Pos = positions[0]; | |
416 | const kingPos = positions[1]; | |
417 | const rook2Pos = positions[2]; | |
418 | ||
419 | // Finally put the shuffled pieces in the board array | |
6808d7a1 BA |
420 | pieces[c][rook1Pos] = "r"; |
421 | pieces[c][knight1Pos] = "n"; | |
422 | pieces[c][bishop1Pos] = "b"; | |
423 | pieces[c][queenPos] = "q"; | |
424 | pieces[c][kingPos] = "k"; | |
425 | pieces[c][bishop2Pos] = "b"; | |
426 | pieces[c][knight2Pos] = "n"; | |
427 | pieces[c][rook2Pos] = "r"; | |
3a2a7b5f | 428 | flags += V.CoordToColumn(rook1Pos) + V.CoordToColumn(rook2Pos); |
1c9f093d | 429 | } |
e3e2cc44 | 430 | // Add turn + flags + enpassant |
6808d7a1 BA |
431 | return ( |
432 | pieces["b"].join("") + | |
1c9f093d BA |
433 | "/pppppppp/8/8/8/8/PPPPPPPP/" + |
434 | pieces["w"].join("").toUpperCase() + | |
3a2a7b5f | 435 | " w 0 " + flags + " -" |
e3e2cc44 | 436 | ); |
1c9f093d BA |
437 | } |
438 | ||
439 | // "Parse" FEN: just return untransformed string data | |
6808d7a1 | 440 | static ParseFen(fen) { |
1c9f093d | 441 | const fenParts = fen.split(" "); |
6808d7a1 | 442 | let res = { |
1c9f093d BA |
443 | position: fenParts[0], |
444 | turn: fenParts[1], | |
6808d7a1 | 445 | movesCount: fenParts[2] |
1c9f093d BA |
446 | }; |
447 | let nextIdx = 3; | |
6808d7a1 BA |
448 | if (V.HasFlags) Object.assign(res, { flags: fenParts[nextIdx++] }); |
449 | if (V.HasEnpassant) Object.assign(res, { enpassant: fenParts[nextIdx] }); | |
1c9f093d BA |
450 | return res; |
451 | } | |
452 | ||
453 | // Return current fen (game state) | |
6808d7a1 BA |
454 | getFen() { |
455 | return ( | |
f9c36b2d BA |
456 | this.getBaseFen() + " " + |
457 | this.getTurnFen() + " " + | |
6808d7a1 BA |
458 | this.movesCount + |
459 | (V.HasFlags ? " " + this.getFlagsFen() : "") + | |
460 | (V.HasEnpassant ? " " + this.getEnpassantFen() : "") | |
461 | ); | |
1c9f093d BA |
462 | } |
463 | ||
f9c36b2d BA |
464 | getFenForRepeat() { |
465 | // Omit movesCount, only variable allowed to differ | |
466 | return ( | |
467 | this.getBaseFen() + "_" + | |
468 | this.getTurnFen() + | |
469 | (V.HasFlags ? "_" + this.getFlagsFen() : "") + | |
470 | (V.HasEnpassant ? "_" + this.getEnpassantFen() : "") | |
471 | ); | |
472 | } | |
473 | ||
1c9f093d | 474 | // Position part of the FEN string |
6808d7a1 | 475 | getBaseFen() { |
6f2f9437 BA |
476 | const format = (count) => { |
477 | // if more than 9 consecutive free spaces, break the integer, | |
478 | // otherwise FEN parsing will fail. | |
479 | if (count <= 9) return count; | |
7c05a5f2 BA |
480 | // Most boards of size < 18: |
481 | if (count <= 18) return "9" + (count - 9); | |
482 | // Except Gomoku: | |
483 | return "99" + (count - 18); | |
6f2f9437 | 484 | }; |
1c9f093d | 485 | let position = ""; |
6808d7a1 | 486 | for (let i = 0; i < V.size.x; i++) { |
1c9f093d | 487 | let emptyCount = 0; |
6808d7a1 BA |
488 | for (let j = 0; j < V.size.y; j++) { |
489 | if (this.board[i][j] == V.EMPTY) emptyCount++; | |
490 | else { | |
491 | if (emptyCount > 0) { | |
1c9f093d | 492 | // Add empty squares in-between |
6f2f9437 | 493 | position += format(emptyCount); |
1c9f093d BA |
494 | emptyCount = 0; |
495 | } | |
496 | position += V.board2fen(this.board[i][j]); | |
497 | } | |
498 | } | |
6808d7a1 | 499 | if (emptyCount > 0) { |
1c9f093d | 500 | // "Flush remainder" |
6f2f9437 | 501 | position += format(emptyCount); |
1c9f093d | 502 | } |
6808d7a1 | 503 | if (i < V.size.x - 1) position += "/"; //separate rows |
1c9f093d BA |
504 | } |
505 | return position; | |
506 | } | |
507 | ||
6808d7a1 | 508 | getTurnFen() { |
1c9f093d BA |
509 | return this.turn; |
510 | } | |
511 | ||
512 | // Flags part of the FEN string | |
6808d7a1 | 513 | getFlagsFen() { |
1c9f093d | 514 | let flags = ""; |
3a2a7b5f BA |
515 | // Castling flags |
516 | for (let c of ["w", "b"]) | |
517 | flags += this.castleFlags[c].map(V.CoordToColumn).join(""); | |
1c9f093d BA |
518 | return flags; |
519 | } | |
520 | ||
521 | // Enpassant part of the FEN string | |
6808d7a1 | 522 | getEnpassantFen() { |
1c9f093d | 523 | const L = this.epSquares.length; |
6808d7a1 BA |
524 | if (!this.epSquares[L - 1]) return "-"; //no en-passant |
525 | return V.CoordsToSquare(this.epSquares[L - 1]); | |
1c9f093d BA |
526 | } |
527 | ||
528 | // Turn position fen into double array ["wb","wp","bk",...] | |
6808d7a1 | 529 | static GetBoard(position) { |
1c9f093d BA |
530 | const rows = position.split("/"); |
531 | let board = ArrayFun.init(V.size.x, V.size.y, ""); | |
6808d7a1 | 532 | for (let i = 0; i < rows.length; i++) { |
1c9f093d | 533 | let j = 0; |
6808d7a1 | 534 | for (let indexInRow = 0; indexInRow < rows[i].length; indexInRow++) { |
1c9f093d | 535 | const character = rows[i][indexInRow]; |
e50a8025 | 536 | const num = parseInt(character, 10); |
a13cbc0f | 537 | // If num is a number, just shift j: |
6808d7a1 | 538 | if (!isNaN(num)) j += num; |
a13cbc0f | 539 | // Else: something at position i,j |
6808d7a1 | 540 | else board[i][j++] = V.fen2board(character); |
1c9f093d BA |
541 | } |
542 | } | |
543 | return board; | |
544 | } | |
545 | ||
546 | // Extract (relevant) flags from fen | |
6808d7a1 | 547 | setFlags(fenflags) { |
1c9f093d | 548 | // white a-castle, h-castle, black a-castle, h-castle |
bb688df5 | 549 | this.castleFlags = { w: [-1, -1], b: [-1, -1] }; |
3a2a7b5f BA |
550 | for (let i = 0; i < 4; i++) { |
551 | this.castleFlags[i < 2 ? "w" : "b"][i % 2] = | |
552 | V.ColumnToCoord(fenflags.charAt(i)); | |
553 | } | |
1c9f093d BA |
554 | } |
555 | ||
556 | ////////////////// | |
557 | // INITIALIZATION | |
558 | ||
37cdcbf3 | 559 | // Fen string fully describes the game state |
b627d118 BA |
560 | constructor(fen) { |
561 | if (!fen) | |
562 | // In printDiagram() fen isn't supply because only getPpath() is used | |
563 | // TODO: find a better solution! | |
564 | return; | |
1c9f093d BA |
565 | const fenParsed = V.ParseFen(fen); |
566 | this.board = V.GetBoard(fenParsed.position); | |
af34341d | 567 | this.turn = fenParsed.turn; |
e50a8025 | 568 | this.movesCount = parseInt(fenParsed.movesCount, 10); |
1c9f093d BA |
569 | this.setOtherVariables(fen); |
570 | } | |
571 | ||
3a2a7b5f | 572 | // Scan board for kings positions |
9d15c433 | 573 | // TODO: should be done from board, no need for the complete FEN |
3a2a7b5f | 574 | scanKings(fen) { |
2c5d7b20 BA |
575 | // Squares of white and black king: |
576 | this.kingPos = { w: [-1, -1], b: [-1, -1] }; | |
1c9f093d | 577 | const fenRows = V.ParseFen(fen).position.split("/"); |
6808d7a1 | 578 | for (let i = 0; i < fenRows.length; i++) { |
1c9f093d | 579 | let k = 0; //column index on board |
6808d7a1 BA |
580 | for (let j = 0; j < fenRows[i].length; j++) { |
581 | switch (fenRows[i].charAt(j)) { | |
582 | case "k": | |
583 | this.kingPos["b"] = [i, k]; | |
1c9f093d | 584 | break; |
6808d7a1 BA |
585 | case "K": |
586 | this.kingPos["w"] = [i, k]; | |
1c9f093d | 587 | break; |
6808d7a1 | 588 | default: { |
e50a8025 | 589 | const num = parseInt(fenRows[i].charAt(j), 10); |
6808d7a1 BA |
590 | if (!isNaN(num)) k += num - 1; |
591 | } | |
1c9f093d BA |
592 | } |
593 | k++; | |
594 | } | |
595 | } | |
596 | } | |
597 | ||
598 | // Some additional variables from FEN (variant dependant) | |
6808d7a1 | 599 | setOtherVariables(fen) { |
1c9f093d BA |
600 | // Set flags and enpassant: |
601 | const parsedFen = V.ParseFen(fen); | |
6808d7a1 BA |
602 | if (V.HasFlags) this.setFlags(parsedFen.flags); |
603 | if (V.HasEnpassant) { | |
604 | const epSq = | |
605 | parsedFen.enpassant != "-" | |
9bd6786b | 606 | ? this.getEpSquare(parsedFen.enpassant) |
6808d7a1 BA |
607 | : undefined; |
608 | this.epSquares = [epSq]; | |
1c9f093d | 609 | } |
3a2a7b5f BA |
610 | // Search for kings positions: |
611 | this.scanKings(fen); | |
1c9f093d BA |
612 | } |
613 | ||
614 | ///////////////////// | |
615 | // GETTERS & SETTERS | |
616 | ||
6808d7a1 BA |
617 | static get size() { |
618 | return { x: 8, y: 8 }; | |
1c9f093d BA |
619 | } |
620 | ||
0ba6420d | 621 | // Color of thing on square (i,j). 'undefined' if square is empty |
6808d7a1 | 622 | getColor(i, j) { |
1c9f093d BA |
623 | return this.board[i][j].charAt(0); |
624 | } | |
625 | ||
626 | // Piece type on square (i,j). 'undefined' if square is empty | |
6808d7a1 | 627 | getPiece(i, j) { |
1c9f093d BA |
628 | return this.board[i][j].charAt(1); |
629 | } | |
630 | ||
631 | // Get opponent color | |
6808d7a1 BA |
632 | static GetOppCol(color) { |
633 | return color == "w" ? "b" : "w"; | |
1c9f093d BA |
634 | } |
635 | ||
1c9f093d | 636 | // Pieces codes (for a clearer code) |
6808d7a1 BA |
637 | static get PAWN() { |
638 | return "p"; | |
639 | } | |
640 | static get ROOK() { | |
641 | return "r"; | |
642 | } | |
643 | static get KNIGHT() { | |
644 | return "n"; | |
645 | } | |
646 | static get BISHOP() { | |
647 | return "b"; | |
648 | } | |
649 | static get QUEEN() { | |
650 | return "q"; | |
651 | } | |
652 | static get KING() { | |
653 | return "k"; | |
654 | } | |
1c9f093d BA |
655 | |
656 | // For FEN checking: | |
6808d7a1 BA |
657 | static get PIECES() { |
658 | return [V.PAWN, V.ROOK, V.KNIGHT, V.BISHOP, V.QUEEN, V.KING]; | |
1c9f093d BA |
659 | } |
660 | ||
661 | // Empty square | |
6808d7a1 BA |
662 | static get EMPTY() { |
663 | return ""; | |
664 | } | |
1c9f093d BA |
665 | |
666 | // Some pieces movements | |
6808d7a1 | 667 | static get steps() { |
1c9f093d | 668 | return { |
6808d7a1 BA |
669 | r: [ |
670 | [-1, 0], | |
671 | [1, 0], | |
672 | [0, -1], | |
673 | [0, 1] | |
674 | ], | |
675 | n: [ | |
676 | [-1, -2], | |
677 | [-1, 2], | |
678 | [1, -2], | |
679 | [1, 2], | |
680 | [-2, -1], | |
681 | [-2, 1], | |
682 | [2, -1], | |
683 | [2, 1] | |
684 | ], | |
685 | b: [ | |
686 | [-1, -1], | |
687 | [-1, 1], | |
688 | [1, -1], | |
689 | [1, 1] | |
690 | ] | |
1c9f093d BA |
691 | }; |
692 | } | |
693 | ||
694 | //////////////////// | |
695 | // MOVES GENERATION | |
696 | ||
0ba6420d | 697 | // All possible moves from selected square |
173f11dc BA |
698 | getPotentialMovesFrom(sq) { |
699 | switch (this.getPiece(sq[0], sq[1])) { | |
700 | case V.PAWN: return this.getPotentialPawnMoves(sq); | |
701 | case V.ROOK: return this.getPotentialRookMoves(sq); | |
702 | case V.KNIGHT: return this.getPotentialKnightMoves(sq); | |
703 | case V.BISHOP: return this.getPotentialBishopMoves(sq); | |
704 | case V.QUEEN: return this.getPotentialQueenMoves(sq); | |
705 | case V.KING: return this.getPotentialKingMoves(sq); | |
1c9f093d | 706 | } |
2a0672a9 | 707 | return []; //never reached (but some variants may use it: Bario...) |
1c9f093d BA |
708 | } |
709 | ||
710 | // Build a regular move from its initial and destination squares. | |
711 | // tr: transformation | |
6808d7a1 | 712 | getBasicMove([sx, sy], [ex, ey], tr) { |
1c58eb76 | 713 | const initColor = this.getColor(sx, sy); |
7e8a7ea1 | 714 | const initPiece = this.board[sx][sy].charAt(1); |
1c9f093d BA |
715 | let mv = new Move({ |
716 | appear: [ | |
717 | new PiPo({ | |
718 | x: ex, | |
719 | y: ey, | |
173f11dc BA |
720 | c: !!tr ? tr.c : initColor, |
721 | p: !!tr ? tr.p : initPiece | |
1c9f093d BA |
722 | }) |
723 | ], | |
724 | vanish: [ | |
725 | new PiPo({ | |
726 | x: sx, | |
727 | y: sy, | |
1c58eb76 BA |
728 | c: initColor, |
729 | p: initPiece | |
1c9f093d BA |
730 | }) |
731 | ] | |
732 | }); | |
733 | ||
734 | // The opponent piece disappears if we take it | |
6808d7a1 | 735 | if (this.board[ex][ey] != V.EMPTY) { |
1c9f093d BA |
736 | mv.vanish.push( |
737 | new PiPo({ | |
738 | x: ex, | |
739 | y: ey, | |
6808d7a1 | 740 | c: this.getColor(ex, ey), |
7e8a7ea1 | 741 | p: this.board[ex][ey].charAt(1) |
1c9f093d BA |
742 | }) |
743 | ); | |
744 | } | |
1c5bfdf2 | 745 | |
1c9f093d BA |
746 | return mv; |
747 | } | |
748 | ||
749 | // Generic method to find possible moves of non-pawn pieces: | |
750 | // "sliding or jumping" | |
4313762d | 751 | getSlideNJumpMoves([x, y], steps, nbSteps) { |
1c9f093d | 752 | let moves = []; |
6808d7a1 | 753 | outerLoop: for (let step of steps) { |
1c9f093d BA |
754 | let i = x + step[0]; |
755 | let j = y + step[1]; | |
4313762d | 756 | let stepCounter = 0; |
6808d7a1 BA |
757 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
758 | moves.push(this.getBasicMove([x, y], [i, j])); | |
4313762d | 759 | if (nbSteps && ++stepCounter >= nbSteps) continue outerLoop; |
1c9f093d BA |
760 | i += step[0]; |
761 | j += step[1]; | |
762 | } | |
6808d7a1 BA |
763 | if (V.OnBoard(i, j) && this.canTake([x, y], [i, j])) |
764 | moves.push(this.getBasicMove([x, y], [i, j])); | |
1c9f093d BA |
765 | } |
766 | return moves; | |
767 | } | |
768 | ||
32f6285e BA |
769 | // Special case of en-passant captures: treated separately |
770 | getEnpassantCaptures([x, y], shiftX) { | |
771 | const Lep = this.epSquares.length; | |
772 | const epSquare = this.epSquares[Lep - 1]; //always at least one element | |
773 | let enpassantMove = null; | |
774 | if ( | |
775 | !!epSquare && | |
776 | epSquare.x == x + shiftX && | |
777 | Math.abs(epSquare.y - y) == 1 | |
778 | ) { | |
779 | enpassantMove = this.getBasicMove([x, y], [epSquare.x, epSquare.y]); | |
780 | enpassantMove.vanish.push({ | |
781 | x: x, | |
782 | y: epSquare.y, | |
7e8a7ea1 | 783 | p: this.board[x][epSquare.y].charAt(1), |
32f6285e BA |
784 | c: this.getColor(x, epSquare.y) |
785 | }); | |
786 | } | |
787 | return !!enpassantMove ? [enpassantMove] : []; | |
788 | } | |
789 | ||
1c58eb76 BA |
790 | // Consider all potential promotions: |
791 | addPawnMoves([x1, y1], [x2, y2], moves, promotions) { | |
792 | let finalPieces = [V.PAWN]; | |
af34341d | 793 | const color = this.turn; //this.getColor(x1, y1); |
1c58eb76 BA |
794 | const lastRank = (color == "w" ? 0 : V.size.x - 1); |
795 | if (x2 == lastRank) { | |
796 | // promotions arg: special override for Hiddenqueen variant | |
797 | if (!!promotions) finalPieces = promotions; | |
15d69043 | 798 | else if (!!V.PawnSpecs.promotions) finalPieces = V.PawnSpecs.promotions; |
1c58eb76 | 799 | } |
1c58eb76 | 800 | for (let piece of finalPieces) { |
3b98a861 | 801 | const tr = (piece != V.PAWN ? { c: color, p: piece } : null); |
1c58eb76 BA |
802 | moves.push(this.getBasicMove([x1, y1], [x2, y2], tr)); |
803 | } | |
804 | } | |
805 | ||
1c9f093d | 806 | // What are the pawn moves from square x,y ? |
32f6285e | 807 | getPotentialPawnMoves([x, y], promotions) { |
af34341d | 808 | const color = this.turn; //this.getColor(x, y); |
6808d7a1 | 809 | const [sizeX, sizeY] = [V.size.x, V.size.y]; |
32f6285e | 810 | const pawnShiftX = V.PawnSpecs.directions[color]; |
1c58eb76 | 811 | const firstRank = (color == "w" ? sizeX - 1 : 0); |
0b8bd121 | 812 | const forward = (color == 'w' ? -1 : 1); |
32f6285e BA |
813 | |
814 | // Pawn movements in shiftX direction: | |
815 | const getPawnMoves = (shiftX) => { | |
816 | let moves = []; | |
817 | // NOTE: next condition is generally true (no pawn on last rank) | |
818 | if (x + shiftX >= 0 && x + shiftX < sizeX) { | |
819 | if (this.board[x + shiftX][y] == V.EMPTY) { | |
0b8bd121 | 820 | // One square forward (or backward) |
1c58eb76 | 821 | this.addPawnMoves([x, y], [x + shiftX, y], moves, promotions); |
32f6285e BA |
822 | // Next condition because pawns on 1st rank can generally jump |
823 | if ( | |
824 | V.PawnSpecs.twoSquares && | |
472c0c4f BA |
825 | ( |
826 | (color == 'w' && x >= V.size.x - 1 - V.PawnSpecs.initShift['w']) | |
827 | || | |
828 | (color == 'b' && x <= V.PawnSpecs.initShift['b']) | |
829 | ) | |
32f6285e | 830 | ) { |
0b8bd121 BA |
831 | if ( |
832 | shiftX == forward && | |
833 | this.board[x + 2 * shiftX][y] == V.EMPTY | |
834 | ) { | |
472c0c4f BA |
835 | // Two squares jump |
836 | moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y])); | |
837 | if ( | |
838 | V.PawnSpecs.threeSquares && | |
839 | this.board[x + 3 * shiftX][y] == V.EMPTY | |
840 | ) { | |
841 | // Three squares jump | |
842 | moves.push(this.getBasicMove([x, y], [x + 3 * shiftX, y])); | |
843 | } | |
844 | } | |
32f6285e BA |
845 | } |
846 | } | |
847 | // Captures | |
848 | if (V.PawnSpecs.canCapture) { | |
849 | for (let shiftY of [-1, 1]) { | |
15d69043 | 850 | if (y + shiftY >= 0 && y + shiftY < sizeY) { |
32f6285e BA |
851 | if ( |
852 | this.board[x + shiftX][y + shiftY] != V.EMPTY && | |
853 | this.canTake([x, y], [x + shiftX, y + shiftY]) | |
854 | ) { | |
1c58eb76 BA |
855 | this.addPawnMoves( |
856 | [x, y], [x + shiftX, y + shiftY], | |
857 | moves, promotions | |
858 | ); | |
32f6285e BA |
859 | } |
860 | if ( | |
0b8bd121 | 861 | V.PawnSpecs.captureBackward && shiftX == forward && |
32f6285e BA |
862 | x - shiftX >= 0 && x - shiftX < V.size.x && |
863 | this.board[x - shiftX][y + shiftY] != V.EMPTY && | |
864 | this.canTake([x, y], [x - shiftX, y + shiftY]) | |
865 | ) { | |
1c58eb76 | 866 | this.addPawnMoves( |
0b8bd121 | 867 | [x, y], [x - shiftX, y + shiftY], |
1c58eb76 BA |
868 | moves, promotions |
869 | ); | |
32f6285e BA |
870 | } |
871 | } | |
1c9f093d BA |
872 | } |
873 | } | |
874 | } | |
32f6285e | 875 | return moves; |
1c9f093d BA |
876 | } |
877 | ||
32f6285e BA |
878 | let pMoves = getPawnMoves(pawnShiftX); |
879 | if (V.PawnSpecs.bidirectional) | |
880 | pMoves = pMoves.concat(getPawnMoves(-pawnShiftX)); | |
881 | ||
6808d7a1 | 882 | if (V.HasEnpassant) { |
32f6285e BA |
883 | // NOTE: backward en-passant captures are not considered |
884 | // because no rules define them (for now). | |
885 | Array.prototype.push.apply( | |
886 | pMoves, | |
887 | this.getEnpassantCaptures([x, y], pawnShiftX) | |
888 | ); | |
1c9f093d | 889 | } |
294fe29f | 890 | |
32f6285e | 891 | return pMoves; |
1c9f093d BA |
892 | } |
893 | ||
894 | // What are the rook moves from square x,y ? | |
6808d7a1 | 895 | getPotentialRookMoves(sq) { |
1c9f093d BA |
896 | return this.getSlideNJumpMoves(sq, V.steps[V.ROOK]); |
897 | } | |
898 | ||
899 | // What are the knight moves from square x,y ? | |
6808d7a1 | 900 | getPotentialKnightMoves(sq) { |
4313762d | 901 | return this.getSlideNJumpMoves(sq, V.steps[V.KNIGHT], 1); |
1c9f093d BA |
902 | } |
903 | ||
904 | // What are the bishop moves from square x,y ? | |
6808d7a1 | 905 | getPotentialBishopMoves(sq) { |
1c9f093d BA |
906 | return this.getSlideNJumpMoves(sq, V.steps[V.BISHOP]); |
907 | } | |
908 | ||
909 | // What are the queen moves from square x,y ? | |
6808d7a1 BA |
910 | getPotentialQueenMoves(sq) { |
911 | return this.getSlideNJumpMoves( | |
4313762d | 912 | sq, V.steps[V.ROOK].concat(V.steps[V.BISHOP])); |
1c9f093d BA |
913 | } |
914 | ||
915 | // What are the king moves from square x,y ? | |
6808d7a1 | 916 | getPotentialKingMoves(sq) { |
1c9f093d | 917 | // Initialize with normal moves |
c583ef1c | 918 | let moves = this.getSlideNJumpMoves( |
4313762d | 919 | sq, V.steps[V.ROOK].concat(V.steps[V.BISHOP]), 1); |
7e8a7ea1 BA |
920 | if (V.HasCastle && this.castleFlags[this.turn].some(v => v < V.size.y)) |
921 | moves = moves.concat(this.getCastleMoves(sq)); | |
c583ef1c | 922 | return moves; |
1c9f093d BA |
923 | } |
924 | ||
a6836242 | 925 | // "castleInCheck" arg to let some variants castle under check |
7e8a7ea1 | 926 | getCastleMoves([x, y], finalSquares, castleInCheck, castleWith) { |
6808d7a1 | 927 | const c = this.getColor(x, y); |
1c9f093d BA |
928 | |
929 | // Castling ? | |
930 | const oppCol = V.GetOppCol(c); | |
931 | let moves = []; | |
9bd6786b | 932 | // King, then rook: |
7e8a7ea1 BA |
933 | finalSquares = finalSquares || [ [2, 3], [V.size.y - 2, V.size.y - 3] ]; |
934 | const castlingKing = this.board[x][y].charAt(1); | |
6808d7a1 BA |
935 | castlingCheck: for ( |
936 | let castleSide = 0; | |
937 | castleSide < 2; | |
938 | castleSide++ //large, then small | |
939 | ) { | |
3a2a7b5f | 940 | if (this.castleFlags[c][castleSide] >= V.size.y) continue; |
3f22c2c3 | 941 | // If this code is reached, rook and king are on initial position |
1c9f093d | 942 | |
2c5d7b20 | 943 | // NOTE: in some variants this is not a rook |
32f6285e | 944 | const rookPos = this.castleFlags[c][castleSide]; |
7e8a7ea1 | 945 | const castlingPiece = this.board[x][rookPos].charAt(1); |
85a1dcba BA |
946 | if ( |
947 | this.board[x][rookPos] == V.EMPTY || | |
948 | this.getColor(x, rookPos) != c || | |
7e8a7ea1 | 949 | (!!castleWith && !castleWith.includes(castlingPiece)) |
85a1dcba | 950 | ) { |
61656127 | 951 | // Rook is not here, or changed color (see Benedict) |
32f6285e | 952 | continue; |
85a1dcba | 953 | } |
32f6285e | 954 | |
2beba6db BA |
955 | // Nothing on the path of the king ? (and no checks) |
956 | const finDist = finalSquares[castleSide][0] - y; | |
957 | let step = finDist / Math.max(1, Math.abs(finDist)); | |
059f0aa2 | 958 | let i = y; |
6808d7a1 BA |
959 | do { |
960 | if ( | |
7e8a7ea1 BA |
961 | (!castleInCheck && this.isAttacked([x, i], oppCol)) || |
962 | ( | |
963 | this.board[x][i] != V.EMPTY && | |
6808d7a1 | 964 | // NOTE: next check is enough, because of chessboard constraints |
7e8a7ea1 BA |
965 | (this.getColor(x, i) != c || ![y, rookPos].includes(i)) |
966 | ) | |
6808d7a1 | 967 | ) { |
1c9f093d BA |
968 | continue castlingCheck; |
969 | } | |
2beba6db | 970 | i += step; |
6808d7a1 | 971 | } while (i != finalSquares[castleSide][0]); |
1c9f093d BA |
972 | |
973 | // Nothing on the path to the rook? | |
6808d7a1 | 974 | step = castleSide == 0 ? -1 : 1; |
3a2a7b5f | 975 | for (i = y + step; i != rookPos; i += step) { |
6808d7a1 | 976 | if (this.board[x][i] != V.EMPTY) continue castlingCheck; |
1c9f093d | 977 | } |
1c9f093d BA |
978 | |
979 | // Nothing on final squares, except maybe king and castling rook? | |
6808d7a1 BA |
980 | for (i = 0; i < 2; i++) { |
981 | if ( | |
5e1bc651 | 982 | finalSquares[castleSide][i] != rookPos && |
6808d7a1 | 983 | this.board[x][finalSquares[castleSide][i]] != V.EMPTY && |
5e1bc651 | 984 | ( |
7e8a7ea1 | 985 | finalSquares[castleSide][i] != y || |
5e1bc651 BA |
986 | this.getColor(x, finalSquares[castleSide][i]) != c |
987 | ) | |
6808d7a1 | 988 | ) { |
1c9f093d BA |
989 | continue castlingCheck; |
990 | } | |
991 | } | |
992 | ||
993 | // If this code is reached, castle is valid | |
6808d7a1 BA |
994 | moves.push( |
995 | new Move({ | |
996 | appear: [ | |
2c5d7b20 BA |
997 | new PiPo({ |
998 | x: x, | |
999 | y: finalSquares[castleSide][0], | |
7e8a7ea1 | 1000 | p: castlingKing, |
2c5d7b20 BA |
1001 | c: c |
1002 | }), | |
1003 | new PiPo({ | |
1004 | x: x, | |
1005 | y: finalSquares[castleSide][1], | |
1006 | p: castlingPiece, | |
1007 | c: c | |
1008 | }) | |
6808d7a1 BA |
1009 | ], |
1010 | vanish: [ | |
7e8a7ea1 | 1011 | // King might be initially disguised (Titan...) |
a19caec0 | 1012 | new PiPo({ x: x, y: y, p: castlingKing, c: c }), |
a6836242 | 1013 | new PiPo({ x: x, y: rookPos, p: castlingPiece, c: c }) |
6808d7a1 BA |
1014 | ], |
1015 | end: | |
1016 | Math.abs(y - rookPos) <= 2 | |
1017 | ? { x: x, y: rookPos } | |
1018 | : { x: x, y: y + 2 * (castleSide == 0 ? -1 : 1) } | |
1019 | }) | |
1020 | ); | |
1c9f093d BA |
1021 | } |
1022 | ||
1023 | return moves; | |
1024 | } | |
1025 | ||
1026 | //////////////////// | |
1027 | // MOVES VALIDATION | |
1028 | ||
1029 | // For the interface: possible moves for the current turn from square sq | |
6808d7a1 BA |
1030 | getPossibleMovesFrom(sq) { |
1031 | return this.filterValid(this.getPotentialMovesFrom(sq)); | |
1c9f093d BA |
1032 | } |
1033 | ||
1034 | // TODO: promotions (into R,B,N,Q) should be filtered only once | |
6808d7a1 BA |
1035 | filterValid(moves) { |
1036 | if (moves.length == 0) return []; | |
1c9f093d BA |
1037 | const color = this.turn; |
1038 | return moves.filter(m => { | |
1039 | this.play(m); | |
1040 | const res = !this.underCheck(color); | |
1041 | this.undo(m); | |
1042 | return res; | |
1043 | }); | |
1044 | } | |
1045 | ||
5e1bc651 | 1046 | getAllPotentialMoves() { |
1c9f093d | 1047 | const color = this.turn; |
1c9f093d | 1048 | let potentialMoves = []; |
6808d7a1 BA |
1049 | for (let i = 0; i < V.size.x; i++) { |
1050 | for (let j = 0; j < V.size.y; j++) { | |
156986e6 | 1051 | if (this.board[i][j] != V.EMPTY && this.getColor(i, j) == color) { |
6808d7a1 BA |
1052 | Array.prototype.push.apply( |
1053 | potentialMoves, | |
1054 | this.getPotentialMovesFrom([i, j]) | |
1055 | ); | |
1c9f093d BA |
1056 | } |
1057 | } | |
1058 | } | |
5e1bc651 BA |
1059 | return potentialMoves; |
1060 | } | |
1061 | ||
1062 | // Search for all valid moves considering current turn | |
1063 | // (for engine and game end) | |
1064 | getAllValidMoves() { | |
1065 | return this.filterValid(this.getAllPotentialMoves()); | |
1c9f093d BA |
1066 | } |
1067 | ||
1068 | // Stop at the first move found | |
2c5d7b20 | 1069 | // TODO: not really, it explores all moves from a square (one is enough). |
cdab5663 BA |
1070 | // Possible fix: add extra arg "oneMove" to getPotentialMovesFrom, |
1071 | // and then return only boolean true at first move found | |
1072 | // (in all getPotentialXXXMoves() ... for all variants ...) | |
6808d7a1 | 1073 | atLeastOneMove() { |
1c9f093d | 1074 | const color = this.turn; |
6808d7a1 BA |
1075 | for (let i = 0; i < V.size.x; i++) { |
1076 | for (let j = 0; j < V.size.y; j++) { | |
665eed90 | 1077 | if (this.board[i][j] != V.EMPTY && this.getColor(i, j) == color) { |
6808d7a1 BA |
1078 | const moves = this.getPotentialMovesFrom([i, j]); |
1079 | if (moves.length > 0) { | |
107dc1bd | 1080 | for (let k = 0; k < moves.length; k++) |
6808d7a1 | 1081 | if (this.filterValid([moves[k]]).length > 0) return true; |
1c9f093d BA |
1082 | } |
1083 | } | |
1084 | } | |
1085 | } | |
1086 | return false; | |
1087 | } | |
1088 | ||
68e19a44 BA |
1089 | // Check if pieces of given color are attacking (king) on square x,y |
1090 | isAttacked(sq, color) { | |
6808d7a1 | 1091 | return ( |
68e19a44 BA |
1092 | this.isAttackedByPawn(sq, color) || |
1093 | this.isAttackedByRook(sq, color) || | |
1094 | this.isAttackedByKnight(sq, color) || | |
1095 | this.isAttackedByBishop(sq, color) || | |
1096 | this.isAttackedByQueen(sq, color) || | |
1097 | this.isAttackedByKing(sq, color) | |
6808d7a1 | 1098 | ); |
1c9f093d BA |
1099 | } |
1100 | ||
d1be8046 | 1101 | // Generic method for non-pawn pieces ("sliding or jumping"): |
68e19a44 | 1102 | // is x,y attacked by a piece of given color ? |
4313762d | 1103 | isAttackedBySlideNJump([x, y], color, piece, steps, nbSteps) { |
d1be8046 BA |
1104 | for (let step of steps) { |
1105 | let rx = x + step[0], | |
1106 | ry = y + step[1]; | |
4313762d BA |
1107 | let stepCounter = 1; |
1108 | while ( | |
1109 | V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && | |
1110 | (!nbSteps || stepCounter < nbSteps) | |
1111 | ) { | |
d1be8046 BA |
1112 | rx += step[0]; |
1113 | ry += step[1]; | |
4313762d | 1114 | stepCounter++; |
d1be8046 BA |
1115 | } |
1116 | if ( | |
1117 | V.OnBoard(rx, ry) && | |
3cf54395 | 1118 | this.board[rx][ry] != V.EMPTY && |
68e19a44 | 1119 | this.getPiece(rx, ry) == piece && |
da9e846e | 1120 | this.getColor(rx, ry) == color |
d1be8046 BA |
1121 | ) { |
1122 | return true; | |
1123 | } | |
1124 | } | |
1125 | return false; | |
1126 | } | |
1127 | ||
68e19a44 | 1128 | // Is square x,y attacked by 'color' pawns ? |
107dc1bd | 1129 | isAttackedByPawn(sq, color) { |
68e19a44 | 1130 | const pawnShift = (color == "w" ? 1 : -1); |
107dc1bd BA |
1131 | return this.isAttackedBySlideNJump( |
1132 | sq, | |
1133 | color, | |
1134 | V.PAWN, | |
1135 | [[pawnShift, 1], [pawnShift, -1]], | |
1136 | "oneStep" | |
1137 | ); | |
1c9f093d BA |
1138 | } |
1139 | ||
68e19a44 BA |
1140 | // Is square x,y attacked by 'color' rooks ? |
1141 | isAttackedByRook(sq, color) { | |
1142 | return this.isAttackedBySlideNJump(sq, color, V.ROOK, V.steps[V.ROOK]); | |
1c9f093d BA |
1143 | } |
1144 | ||
68e19a44 BA |
1145 | // Is square x,y attacked by 'color' knights ? |
1146 | isAttackedByKnight(sq, color) { | |
6808d7a1 BA |
1147 | return this.isAttackedBySlideNJump( |
1148 | sq, | |
68e19a44 | 1149 | color, |
6808d7a1 BA |
1150 | V.KNIGHT, |
1151 | V.steps[V.KNIGHT], | |
1152 | "oneStep" | |
1153 | ); | |
1c9f093d BA |
1154 | } |
1155 | ||
68e19a44 BA |
1156 | // Is square x,y attacked by 'color' bishops ? |
1157 | isAttackedByBishop(sq, color) { | |
1158 | return this.isAttackedBySlideNJump(sq, color, V.BISHOP, V.steps[V.BISHOP]); | |
1c9f093d BA |
1159 | } |
1160 | ||
68e19a44 BA |
1161 | // Is square x,y attacked by 'color' queens ? |
1162 | isAttackedByQueen(sq, color) { | |
6808d7a1 BA |
1163 | return this.isAttackedBySlideNJump( |
1164 | sq, | |
68e19a44 | 1165 | color, |
6808d7a1 BA |
1166 | V.QUEEN, |
1167 | V.steps[V.ROOK].concat(V.steps[V.BISHOP]) | |
1168 | ); | |
1c9f093d BA |
1169 | } |
1170 | ||
68e19a44 BA |
1171 | // Is square x,y attacked by 'color' king(s) ? |
1172 | isAttackedByKing(sq, color) { | |
6808d7a1 BA |
1173 | return this.isAttackedBySlideNJump( |
1174 | sq, | |
68e19a44 | 1175 | color, |
6808d7a1 BA |
1176 | V.KING, |
1177 | V.steps[V.ROOK].concat(V.steps[V.BISHOP]), | |
1178 | "oneStep" | |
1179 | ); | |
1c9f093d BA |
1180 | } |
1181 | ||
1c9f093d | 1182 | // Is color under check after his move ? |
6808d7a1 | 1183 | underCheck(color) { |
1c58eb76 | 1184 | return this.isAttacked(this.kingPos[color], V.GetOppCol(color)); |
1c9f093d BA |
1185 | } |
1186 | ||
1187 | ///////////////// | |
1188 | // MOVES PLAYING | |
1189 | ||
1190 | // Apply a move on board | |
6808d7a1 BA |
1191 | static PlayOnBoard(board, move) { |
1192 | for (let psq of move.vanish) board[psq.x][psq.y] = V.EMPTY; | |
1193 | for (let psq of move.appear) board[psq.x][psq.y] = psq.c + psq.p; | |
1c9f093d BA |
1194 | } |
1195 | // Un-apply the played move | |
6808d7a1 BA |
1196 | static UndoOnBoard(board, move) { |
1197 | for (let psq of move.appear) board[psq.x][psq.y] = V.EMPTY; | |
1198 | for (let psq of move.vanish) board[psq.x][psq.y] = psq.c + psq.p; | |
1c9f093d BA |
1199 | } |
1200 | ||
3a2a7b5f BA |
1201 | prePlay() {} |
1202 | ||
1203 | play(move) { | |
1204 | // DEBUG: | |
1205 | // if (!this.states) this.states = []; | |
1c58eb76 | 1206 | // const stateFen = this.getFen() + JSON.stringify(this.kingPos); |
3a2a7b5f BA |
1207 | // this.states.push(stateFen); |
1208 | ||
1209 | this.prePlay(move); | |
2c5d7b20 BA |
1210 | // Save flags (for undo) |
1211 | if (V.HasFlags) move.flags = JSON.stringify(this.aggregateFlags()); | |
3a2a7b5f BA |
1212 | if (V.HasEnpassant) this.epSquares.push(this.getEpSquare(move)); |
1213 | V.PlayOnBoard(this.board, move); | |
1214 | this.turn = V.GetOppCol(this.turn); | |
1215 | this.movesCount++; | |
1216 | this.postPlay(move); | |
1217 | } | |
1218 | ||
a9e1202b | 1219 | updateCastleFlags(move, piece, color) { |
4258b58c | 1220 | // TODO: check flags. If already off, no need to always re-evaluate |
a9e1202b | 1221 | const c = color || V.GetOppCol(this.turn); |
1c58eb76 BA |
1222 | const firstRank = (c == "w" ? V.size.x - 1 : 0); |
1223 | // Update castling flags if rooks are moved | |
c7550017 | 1224 | const oppCol = this.turn; |
1c58eb76 | 1225 | const oppFirstRank = V.size.x - 1 - firstRank; |
bb688df5 BA |
1226 | if (piece == V.KING && move.appear.length > 0) |
1227 | this.castleFlags[c] = [V.size.y, V.size.y]; | |
1228 | else if ( | |
1c58eb76 BA |
1229 | move.start.x == firstRank && //our rook moves? |
1230 | this.castleFlags[c].includes(move.start.y) | |
1231 | ) { | |
1232 | const flagIdx = (move.start.y == this.castleFlags[c][0] ? 0 : 1); | |
1233 | this.castleFlags[c][flagIdx] = V.size.y; | |
305ede7e BA |
1234 | } |
1235 | // NOTE: not "else if" because a rook could take an opposing rook | |
1236 | if ( | |
1c58eb76 BA |
1237 | move.end.x == oppFirstRank && //we took opponent rook? |
1238 | this.castleFlags[oppCol].includes(move.end.y) | |
1239 | ) { | |
1240 | const flagIdx = (move.end.y == this.castleFlags[oppCol][0] ? 0 : 1); | |
1241 | this.castleFlags[oppCol][flagIdx] = V.size.y; | |
1242 | } | |
1243 | } | |
1244 | ||
1c9f093d | 1245 | // After move is played, update variables + flags |
3a2a7b5f BA |
1246 | postPlay(move) { |
1247 | const c = V.GetOppCol(this.turn); | |
1c9f093d | 1248 | let piece = undefined; |
3a2a7b5f | 1249 | if (move.vanish.length >= 1) |
1c9f093d BA |
1250 | // Usual case, something is moved |
1251 | piece = move.vanish[0].p; | |
3a2a7b5f | 1252 | else |
1c9f093d BA |
1253 | // Crazyhouse-like variants |
1254 | piece = move.appear[0].p; | |
1c9f093d BA |
1255 | |
1256 | // Update king position + flags | |
964eda04 BA |
1257 | if (piece == V.KING && move.appear.length > 0) |
1258 | this.kingPos[c] = [move.appear[0].x, move.appear[0].y]; | |
bb688df5 | 1259 | if (V.HasCastle) this.updateCastleFlags(move, piece); |
1c9f093d BA |
1260 | } |
1261 | ||
3a2a7b5f | 1262 | preUndo() {} |
1c9f093d | 1263 | |
6808d7a1 | 1264 | undo(move) { |
3a2a7b5f | 1265 | this.preUndo(move); |
6808d7a1 BA |
1266 | if (V.HasEnpassant) this.epSquares.pop(); |
1267 | if (V.HasFlags) this.disaggregateFlags(JSON.parse(move.flags)); | |
1c9f093d BA |
1268 | V.UndoOnBoard(this.board, move); |
1269 | this.turn = V.GetOppCol(this.turn); | |
1270 | this.movesCount--; | |
3a2a7b5f | 1271 | this.postUndo(move); |
1c9f093d BA |
1272 | |
1273 | // DEBUG: | |
1c58eb76 | 1274 | // const stateFen = this.getFen() + JSON.stringify(this.kingPos); |
9bd6786b BA |
1275 | // if (stateFen != this.states[this.states.length-1]) debugger; |
1276 | // this.states.pop(); | |
1c9f093d BA |
1277 | } |
1278 | ||
3a2a7b5f BA |
1279 | // After move is undo-ed *and flags resetted*, un-update other variables |
1280 | // TODO: more symmetry, by storing flags increment in move (?!) | |
1281 | postUndo(move) { | |
1282 | // (Potentially) Reset king position | |
1283 | const c = this.getColor(move.start.x, move.start.y); | |
1284 | if (this.getPiece(move.start.x, move.start.y) == V.KING) | |
1285 | this.kingPos[c] = [move.start.x, move.start.y]; | |
1286 | } | |
1287 | ||
1c9f093d BA |
1288 | /////////////// |
1289 | // END OF GAME | |
1290 | ||
1291 | // What is the score ? (Interesting if game is over) | |
6808d7a1 | 1292 | getCurrentScore() { |
bb688df5 | 1293 | if (this.atLeastOneMove()) return "*"; |
1c9f093d BA |
1294 | // Game over |
1295 | const color = this.turn; | |
1296 | // No valid move: stalemate or checkmate? | |
bb688df5 | 1297 | if (!this.underCheck(color)) return "1/2"; |
1c9f093d | 1298 | // OK, checkmate |
68e19a44 | 1299 | return (color == "w" ? "0-1" : "1-0"); |
1c9f093d BA |
1300 | } |
1301 | ||
1302 | /////////////// | |
1303 | // ENGINE PLAY | |
1304 | ||
1305 | // Pieces values | |
6808d7a1 | 1306 | static get VALUES() { |
1c9f093d | 1307 | return { |
6808d7a1 BA |
1308 | p: 1, |
1309 | r: 5, | |
1310 | n: 3, | |
1311 | b: 3, | |
1312 | q: 9, | |
1313 | k: 1000 | |
1c9f093d BA |
1314 | }; |
1315 | } | |
1316 | ||
1317 | // "Checkmate" (unreachable eval) | |
6808d7a1 BA |
1318 | static get INFINITY() { |
1319 | return 9999; | |
1320 | } | |
1c9f093d BA |
1321 | |
1322 | // At this value or above, the game is over | |
6808d7a1 BA |
1323 | static get THRESHOLD_MATE() { |
1324 | return V.INFINITY; | |
1325 | } | |
1c9f093d | 1326 | |
2c5d7b20 | 1327 | // Search depth: 1,2 for e.g. higher branching factor, 4 for smaller |
6808d7a1 BA |
1328 | static get SEARCH_DEPTH() { |
1329 | return 3; | |
1330 | } | |
1c9f093d | 1331 | |
af34341d BA |
1332 | // 'movesList' arg for some variants to provide a custom list |
1333 | getComputerMove(movesList) { | |
1c9f093d BA |
1334 | const maxeval = V.INFINITY; |
1335 | const color = this.turn; | |
af34341d | 1336 | let moves1 = movesList || this.getAllValidMoves(); |
c322a844 | 1337 | |
6808d7a1 | 1338 | if (moves1.length == 0) |
e71161fb | 1339 | // TODO: this situation should not happen |
41cb9b94 | 1340 | return null; |
1c9f093d | 1341 | |
b83a675a | 1342 | // Rank moves using a min-max at depth 2 (if search_depth >= 2!) |
6808d7a1 | 1343 | for (let i = 0; i < moves1.length; i++) { |
afbf3ca7 BA |
1344 | this.play(moves1[i]); |
1345 | const score1 = this.getCurrentScore(); | |
1346 | if (score1 != "*") { | |
1347 | moves1[i].eval = | |
1348 | score1 == "1/2" | |
1349 | ? 0 | |
1350 | : (score1 == "1-0" ? 1 : -1) * maxeval; | |
1351 | } | |
1352 | if (V.SEARCH_DEPTH == 1 || score1 != "*") { | |
1353 | if (!moves1[i].eval) moves1[i].eval = this.evalPosition(); | |
1354 | this.undo(moves1[i]); | |
b83a675a BA |
1355 | continue; |
1356 | } | |
1c9f093d | 1357 | // Initial self evaluation is very low: "I'm checkmated" |
6808d7a1 | 1358 | moves1[i].eval = (color == "w" ? -1 : 1) * maxeval; |
afbf3ca7 BA |
1359 | // Initial enemy evaluation is very low too, for him |
1360 | let eval2 = (color == "w" ? 1 : -1) * maxeval; | |
1361 | // Second half-move: | |
1362 | let moves2 = this.getAllValidMoves(); | |
1363 | for (let j = 0; j < moves2.length; j++) { | |
1364 | this.play(moves2[j]); | |
1365 | const score2 = this.getCurrentScore(); | |
1366 | let evalPos = 0; //1/2 value | |
1367 | switch (score2) { | |
1368 | case "*": | |
1369 | evalPos = this.evalPosition(); | |
1370 | break; | |
1371 | case "1-0": | |
1372 | evalPos = maxeval; | |
1373 | break; | |
1374 | case "0-1": | |
1375 | evalPos = -maxeval; | |
1376 | break; | |
1c9f093d | 1377 | } |
afbf3ca7 BA |
1378 | if ( |
1379 | (color == "w" && evalPos < eval2) || | |
1380 | (color == "b" && evalPos > eval2) | |
1381 | ) { | |
1382 | eval2 = evalPos; | |
1383 | } | |
1384 | this.undo(moves2[j]); | |
1385 | } | |
6808d7a1 BA |
1386 | if ( |
1387 | (color == "w" && eval2 > moves1[i].eval) || | |
1388 | (color == "b" && eval2 < moves1[i].eval) | |
1389 | ) { | |
1c9f093d BA |
1390 | moves1[i].eval = eval2; |
1391 | } | |
1392 | this.undo(moves1[i]); | |
1393 | } | |
6808d7a1 BA |
1394 | moves1.sort((a, b) => { |
1395 | return (color == "w" ? 1 : -1) * (b.eval - a.eval); | |
1396 | }); | |
a97bdbda | 1397 | // console.log(moves1.map(m => { return [this.getNotation(m), m.eval]; })); |
1c9f093d | 1398 | |
1c9f093d | 1399 | // Skip depth 3+ if we found a checkmate (or if we are checkmated in 1...) |
6808d7a1 | 1400 | if (V.SEARCH_DEPTH >= 3 && Math.abs(moves1[0].eval) < V.THRESHOLD_MATE) { |
6808d7a1 | 1401 | for (let i = 0; i < moves1.length; i++) { |
1c9f093d BA |
1402 | this.play(moves1[i]); |
1403 | // 0.1 * oldEval : heuristic to avoid some bad moves (not all...) | |
6808d7a1 BA |
1404 | moves1[i].eval = |
1405 | 0.1 * moves1[i].eval + | |
1406 | this.alphabeta(V.SEARCH_DEPTH - 1, -maxeval, maxeval); | |
1c9f093d BA |
1407 | this.undo(moves1[i]); |
1408 | } | |
6808d7a1 BA |
1409 | moves1.sort((a, b) => { |
1410 | return (color == "w" ? 1 : -1) * (b.eval - a.eval); | |
1411 | }); | |
b83a675a | 1412 | } |
1c9f093d | 1413 | |
b83a675a | 1414 | let candidates = [0]; |
d54f6261 BA |
1415 | for (let i = 1; i < moves1.length && moves1[i].eval == moves1[0].eval; i++) |
1416 | candidates.push(i); | |
656b1878 | 1417 | return moves1[candidates[randInt(candidates.length)]]; |
1c9f093d BA |
1418 | } |
1419 | ||
6808d7a1 | 1420 | alphabeta(depth, alpha, beta) { |
1c9f093d BA |
1421 | const maxeval = V.INFINITY; |
1422 | const color = this.turn; | |
1423 | const score = this.getCurrentScore(); | |
1424 | if (score != "*") | |
6808d7a1 BA |
1425 | return score == "1/2" ? 0 : (score == "1-0" ? 1 : -1) * maxeval; |
1426 | if (depth == 0) return this.evalPosition(); | |
a97bdbda | 1427 | const moves = this.getAllValidMoves(); |
6808d7a1 BA |
1428 | let v = color == "w" ? -maxeval : maxeval; |
1429 | if (color == "w") { | |
1430 | for (let i = 0; i < moves.length; i++) { | |
1c9f093d | 1431 | this.play(moves[i]); |
6808d7a1 | 1432 | v = Math.max(v, this.alphabeta(depth - 1, alpha, beta)); |
1c9f093d BA |
1433 | this.undo(moves[i]); |
1434 | alpha = Math.max(alpha, v); | |
6808d7a1 | 1435 | if (alpha >= beta) break; //beta cutoff |
1c9f093d | 1436 | } |
1c5bfdf2 | 1437 | } |
6808d7a1 | 1438 | else { |
1c5bfdf2 | 1439 | // color=="b" |
6808d7a1 | 1440 | for (let i = 0; i < moves.length; i++) { |
1c9f093d | 1441 | this.play(moves[i]); |
6808d7a1 | 1442 | v = Math.min(v, this.alphabeta(depth - 1, alpha, beta)); |
1c9f093d BA |
1443 | this.undo(moves[i]); |
1444 | beta = Math.min(beta, v); | |
6808d7a1 | 1445 | if (alpha >= beta) break; //alpha cutoff |
1c9f093d BA |
1446 | } |
1447 | } | |
1448 | return v; | |
1449 | } | |
1450 | ||
6808d7a1 | 1451 | evalPosition() { |
1c9f093d BA |
1452 | let evaluation = 0; |
1453 | // Just count material for now | |
6808d7a1 BA |
1454 | for (let i = 0; i < V.size.x; i++) { |
1455 | for (let j = 0; j < V.size.y; j++) { | |
1456 | if (this.board[i][j] != V.EMPTY) { | |
1457 | const sign = this.getColor(i, j) == "w" ? 1 : -1; | |
1458 | evaluation += sign * V.VALUES[this.getPiece(i, j)]; | |
1c9f093d BA |
1459 | } |
1460 | } | |
1461 | } | |
1462 | return evaluation; | |
1463 | } | |
1464 | ||
1465 | ///////////////////////// | |
1466 | // MOVES + GAME NOTATION | |
1467 | ///////////////////////// | |
1468 | ||
1469 | // Context: just before move is played, turn hasn't changed | |
1470 | // TODO: un-ambiguous notation (switch on piece type, check directions...) | |
6808d7a1 BA |
1471 | getNotation(move) { |
1472 | if (move.appear.length == 2 && move.appear[0].p == V.KING) | |
1cd3e362 | 1473 | // Castle |
6808d7a1 | 1474 | return move.end.y < move.start.y ? "0-0-0" : "0-0"; |
1c9f093d BA |
1475 | |
1476 | // Translate final square | |
1477 | const finalSquare = V.CoordsToSquare(move.end); | |
1478 | ||
1479 | const piece = this.getPiece(move.start.x, move.start.y); | |
6808d7a1 | 1480 | if (piece == V.PAWN) { |
1c9f093d BA |
1481 | // Pawn move |
1482 | let notation = ""; | |
6808d7a1 | 1483 | if (move.vanish.length > move.appear.length) { |
1c9f093d BA |
1484 | // Capture |
1485 | const startColumn = V.CoordToColumn(move.start.y); | |
1486 | notation = startColumn + "x" + finalSquare; | |
78d64531 | 1487 | } |
6808d7a1 BA |
1488 | else notation = finalSquare; |
1489 | if (move.appear.length > 0 && move.appear[0].p != V.PAWN) | |
78d64531 | 1490 | // Promotion |
1c9f093d BA |
1491 | notation += "=" + move.appear[0].p.toUpperCase(); |
1492 | return notation; | |
1493 | } | |
6808d7a1 BA |
1494 | // Piece movement |
1495 | return ( | |
1496 | piece.toUpperCase() + | |
1497 | (move.vanish.length > move.appear.length ? "x" : "") + | |
1498 | finalSquare | |
1499 | ); | |
1500 | } | |
2c5d7b20 BA |
1501 | |
1502 | static GetUnambiguousNotation(move) { | |
1503 | // Machine-readable format with all the informations about the move | |
1504 | return ( | |
1505 | (!!move.start && V.OnBoard(move.start.x, move.start.y) | |
1506 | ? V.CoordsToSquare(move.start) | |
1507 | : "-" | |
1508 | ) + "." + | |
1509 | (!!move.end && V.OnBoard(move.end.x, move.end.y) | |
1510 | ? V.CoordsToSquare(move.end) | |
1511 | : "-" | |
1512 | ) + " " + | |
1513 | (!!move.appear && move.appear.length > 0 | |
1514 | ? move.appear.map(a => | |
1515 | a.c + a.p + V.CoordsToSquare({ x: a.x, y: a.y })).join(".") | |
1516 | : "-" | |
1517 | ) + "/" + | |
1518 | (!!move.vanish && move.vanish.length > 0 | |
1519 | ? move.vanish.map(a => | |
1520 | a.c + a.p + V.CoordsToSquare({ x: a.x, y: a.y })).join(".") | |
1521 | : "-" | |
1522 | ) | |
1523 | ); | |
1524 | } | |
7e8a7ea1 | 1525 | |
6808d7a1 | 1526 | }; |