Commit | Line | Data |
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b866a62a | 1 | import { ChessRules, Move, PiPo } from "@/base_rules"; |
ad1e629e | 2 | import { randInt } from "@/utils/alea"; |
b866a62a | 3 | |
0d5335de | 4 | export class DynamoRules extends ChessRules { |
7ddfec38 | 5 | // TODO: later, allow to push out pawns on a and h files |
61656127 BA |
6 | static get HasEnpassant() { |
7 | return false; | |
8 | } | |
9 | ||
c7550017 BA |
10 | canIplay(side, [x, y]) { |
11 | // Sometimes opponent's pieces can be moved directly | |
e78633db | 12 | return this.turn == side; |
c7550017 BA |
13 | } |
14 | ||
61656127 BA |
15 | setOtherVariables(fen) { |
16 | super.setOtherVariables(fen); | |
17 | this.subTurn = 1; | |
18 | // Local stack of "action moves" | |
19 | this.amoves = []; | |
20 | const amove = V.ParseFen(fen).amove; | |
93ce6119 | 21 | if (amove != "-") { |
61656127 | 22 | const amoveParts = amove.split("/"); |
ad1e629e | 23 | let move = { |
61656127 BA |
24 | // No need for start & end |
25 | appear: [], | |
26 | vanish: [] | |
27 | }; | |
28 | [0, 1].map(i => { | |
ad1e629e BA |
29 | if (amoveParts[i] != "-") { |
30 | amoveParts[i].split(".").forEach(av => { | |
31 | // Format is "bpe3" | |
32 | const xy = V.SquareToCoords(av.substr(2)); | |
33 | move[i == 0 ? "appear" : "vanish"].push( | |
34 | new PiPo({ | |
35 | x: xy.x, | |
36 | y: xy.y, | |
37 | c: av[0], | |
38 | p: av[1] | |
39 | }) | |
40 | ); | |
41 | }); | |
42 | } | |
61656127 BA |
43 | }); |
44 | this.amoves.push(move); | |
c7550017 | 45 | } |
7b53b5a7 | 46 | this.subTurn = 1; |
a443d256 BA |
47 | // Stack "first moves" (on subTurn 1) to merge and check opposite moves |
48 | this.firstMove = []; | |
c7550017 BA |
49 | } |
50 | ||
61656127 BA |
51 | static ParseFen(fen) { |
52 | return Object.assign( | |
53 | ChessRules.ParseFen(fen), | |
93ce6119 | 54 | { amove: fen.split(" ")[4] } |
61656127 BA |
55 | ); |
56 | } | |
57 | ||
58 | static IsGoodFen(fen) { | |
59 | if (!ChessRules.IsGoodFen(fen)) return false; | |
60 | const fenParts = fen.split(" "); | |
ad1e629e BA |
61 | if (fenParts.length != 5) return false; |
62 | if (fenParts[4] != "-") { | |
63 | // TODO: a single regexp instead. | |
64 | // Format is [bpa2[.wpd3]] || '-'/[bbc3[.wrd5]] || '-' | |
65 | const amoveParts = fenParts[4].split("/"); | |
66 | if (amoveParts.length != 2) return false; | |
67 | for (let part of amoveParts) { | |
68 | if (part != "-") { | |
69 | for (let psq of part.split(".")) | |
70 | if (!psq.match(/^[a-r]{3}[1-8]$/)) return false; | |
71 | } | |
72 | } | |
73 | } | |
61656127 BA |
74 | return true; |
75 | } | |
76 | ||
93ce6119 BA |
77 | getFen() { |
78 | return super.getFen() + " " + this.getAmoveFen(); | |
61656127 BA |
79 | } |
80 | ||
93ce6119 BA |
81 | getFenForRepeat() { |
82 | return super.getFenForRepeat() + "_" + this.getAmoveFen(); | |
83 | } | |
84 | ||
85 | getAmoveFen() { | |
86 | const L = this.amoves.length; | |
7b53b5a7 | 87 | if (L == 0) return "-"; |
93ce6119 BA |
88 | return ( |
89 | ["appear","vanish"].map( | |
90 | mpart => { | |
156986e6 | 91 | if (this.amoves[L-1][mpart].length == 0) return "-"; |
93ce6119 BA |
92 | return ( |
93 | this.amoves[L-1][mpart].map( | |
94 | av => { | |
95 | const square = V.CoordsToSquare({ x: av.x, y: av.y }); | |
96 | return av.c + av.p + square; | |
97 | } | |
98 | ).join(".") | |
99 | ); | |
100 | } | |
101 | ).join("/") | |
102 | ); | |
61656127 BA |
103 | } |
104 | ||
105 | canTake() { | |
106 | // Captures don't occur (only pulls & pushes) | |
107 | return false; | |
108 | } | |
109 | ||
b2655276 BA |
110 | // Step is right, just add (push/pull) moves in this direction |
111 | // Direction is assumed normalized. | |
112 | getMovesInDirection([x, y], [dx, dy], nbSteps) { | |
113 | nbSteps = nbSteps || 8; //max 8 steps anyway | |
114 | let [i, j] = [x + dx, y + dy]; | |
61656127 | 115 | let moves = []; |
b2655276 BA |
116 | const color = this.getColor(x, y); |
117 | const piece = this.getPiece(x, y); | |
118 | const lastRank = (color == 'w' ? 0 : 7); | |
7b53b5a7 | 119 | let counter = 1; |
b2655276 BA |
120 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
121 | if (i == lastRank && piece == V.PAWN) { | |
122 | // Promotion by push or pull | |
123 | V.PawnSpecs.promotions.forEach(p => { | |
124 | let move = super.getBasicMove([x, y], [i, j], { c: color, p: p }); | |
125 | moves.push(move); | |
126 | }); | |
127 | } | |
128 | else moves.push(super.getBasicMove([x, y], [i, j])); | |
7b53b5a7 BA |
129 | if (++counter > nbSteps) break; |
130 | i += dx; | |
131 | j += dy; | |
b2655276 BA |
132 | } |
133 | if (!V.OnBoard(i, j) && piece != V.KING) { | |
134 | // Add special "exit" move, by "taking king" | |
135 | moves.push( | |
136 | new Move({ | |
137 | start: { x: x, y: y }, | |
7b53b5a7 | 138 | end: { x: this.kingPos[color][0], y: this.kingPos[color][1] }, |
b2655276 BA |
139 | appear: [], |
140 | vanish: [{ x: x, y: y, c: color, p: piece }] | |
141 | }) | |
142 | ); | |
143 | } | |
61656127 BA |
144 | return moves; |
145 | } | |
146 | ||
b2655276 BA |
147 | // Normalize direction to know the step |
148 | getNormalizedDirection([dx, dy]) { | |
149 | const absDir = [Math.abs(dx), Math.abs(dy)]; | |
150 | let divisor = 0; | |
151 | if (absDir[0] != 0 && absDir[1] != 0 && absDir[0] != absDir[1]) | |
152 | // Knight | |
153 | divisor = Math.min(absDir[0], absDir[1]); | |
154 | else | |
155 | // Standard slider (or maybe a pawn or king: same) | |
156 | divisor = Math.max(absDir[0], absDir[1]); | |
157 | return [dx / divisor, dy / divisor]; | |
158 | } | |
159 | ||
ad1e629e | 160 | // There was something on x2,y2, maybe our color, pushed/pulled. |
ad1e629e | 161 | isAprioriValidExit([x1, y1], [x2, y2], color2) { |
b2655276 | 162 | const color1 = this.getColor(x1, y1); |
b2655276 | 163 | const pawnShift = (color1 == 'w' ? -1 : 1); |
ad1e629e | 164 | const lastRank = (color1 == 'w' ? 0 : 7); |
b2655276 BA |
165 | const deltaX = Math.abs(x1 - x2); |
166 | const deltaY = Math.abs(y1 - y2); | |
ad1e629e BA |
167 | const checkSlider = () => { |
168 | const dir = this.getNormalizedDirection([x2 - x1, y2 - y1]); | |
169 | let [i, j] = [x1 + dir[0], y1 + dir[1]]; | |
170 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { | |
171 | i += dir[0]; | |
172 | j += dir[1]; | |
173 | } | |
174 | return !V.OnBoard(i, j); | |
175 | }; | |
b2655276 BA |
176 | switch (this.getPiece(x1, y1)) { |
177 | case V.PAWN: | |
178 | return ( | |
ad1e629e | 179 | x1 + pawnShift == x2 && |
b2655276 | 180 | ( |
ad1e629e BA |
181 | (color1 == color2 && x2 == lastRank && y1 == y2) || |
182 | (color1 != color2 && deltaY == 1 && !V.OnBoard(x2, 2 * y2 - y1)) | |
b2655276 BA |
183 | ) |
184 | ); | |
185 | case V.ROOK: | |
ad1e629e BA |
186 | if (x1 != x2 && y1 != y2) return false; |
187 | return checkSlider(); | |
188 | case V.KNIGHT: | |
189 | return ( | |
190 | deltaX + deltaY == 3 && | |
191 | (deltaX == 1 || deltaY == 1) && | |
192 | !V.OnBoard(2 * x2 - x1, 2 * y2 - y1) | |
193 | ); | |
b2655276 | 194 | case V.BISHOP: |
ad1e629e BA |
195 | if (deltaX != deltaY) return false; |
196 | return checkSlider(); | |
b2655276 | 197 | case V.QUEEN: |
ad1e629e BA |
198 | if (deltaX != 0 && deltaY != 0 && deltaX != deltaY) return false; |
199 | return checkSlider(); | |
200 | case V.KING: | |
b2655276 | 201 | return ( |
ad1e629e BA |
202 | deltaX <= 1 && |
203 | deltaY <= 1 && | |
204 | !V.OnBoard(2 * x2 - x1, 2 * y2 - y1) | |
b2655276 | 205 | ); |
93ce6119 | 206 | } |
b2655276 | 207 | return false; |
b866a62a BA |
208 | } |
209 | ||
05d37cc7 BA |
210 | isAprioriValidVertical([x1, y1], x2) { |
211 | const piece = this.getPiece(x1, y1); | |
212 | const deltaX = Math.abs(x1 - x2); | |
213 | const startRank = (this.getColor(x1, y1) == 'w' ? 6 : 1); | |
214 | return ( | |
215 | [V.QUEEN, V.ROOK].includes(piece) || | |
216 | ( | |
217 | [V.KING, V.PAWN].includes(piece) && | |
218 | ( | |
219 | deltaX == 1 || | |
220 | (deltaX == 2 && piece == V.PAWN && x1 == startRank) | |
221 | ) | |
222 | ) | |
223 | ); | |
224 | } | |
225 | ||
93ce6119 | 226 | // NOTE: for pushes, play the pushed piece first. |
61656127 | 227 | // for pulls: play the piece doing the action first |
b2655276 | 228 | // NOTE: to push a piece out of the board, make it slide until its king |
b866a62a BA |
229 | getPotentialMovesFrom([x, y]) { |
230 | const color = this.turn; | |
81e74ee5 | 231 | const sqCol = this.getColor(x, y); |
93ce6119 | 232 | if (this.subTurn == 1) { |
b2655276 BA |
233 | const getMoveHash = (m) => { |
234 | return V.CoordsToSquare(m.start) + V.CoordsToSquare(m.end); | |
235 | }; | |
236 | const addMoves = (dir, nbSteps) => { | |
237 | const newMoves = | |
238 | this.getMovesInDirection([x, y], [-dir[0], -dir[1]], nbSteps) | |
239 | .filter(m => !movesHash[getMoveHash(m)]); | |
7b53b5a7 | 240 | newMoves.forEach(m => { movesHash[getMoveHash(m)] = true; }); |
b2655276 BA |
241 | Array.prototype.push.apply(moves, newMoves); |
242 | }; | |
8c267d0c | 243 | // Free to play any move (if piece of my color): |
cfceecba | 244 | let moves = |
81e74ee5 | 245 | sqCol == color |
8c267d0c BA |
246 | ? super.getPotentialMovesFrom([x, y]) |
247 | : []; | |
cfceecba BA |
248 | // There may be several suicide moves: keep only one |
249 | let hasExit = false; | |
250 | moves = moves.filter(m => { | |
251 | const suicide = (m.appear.length == 0); | |
252 | if (suicide) { | |
253 | if (hasExit) return false; | |
254 | hasExit = true; | |
255 | } | |
256 | return true; | |
257 | }); | |
b2655276 BA |
258 | const pawnShift = (color == 'w' ? -1 : 1); |
259 | const pawnStartRank = (color == 'w' ? 6 : 1); | |
7b53b5a7 BA |
260 | // Structure to avoid adding moves twice (can be action & move) |
261 | let movesHash = {}; | |
262 | moves.forEach(m => { movesHash[getMoveHash(m)] = true; }); | |
b2655276 BA |
263 | // [x, y] is pushed by 'color' |
264 | for (let step of V.steps[V.KNIGHT]) { | |
265 | const [i, j] = [x + step[0], y + step[1]]; | |
7b53b5a7 BA |
266 | if ( |
267 | V.OnBoard(i, j) && | |
268 | this.board[i][j] != V.EMPTY && | |
269 | this.getColor(i, j) == color && | |
270 | this.getPiece(i, j) == V.KNIGHT | |
271 | ) { | |
272 | addMoves(step, 1); | |
b2655276 BA |
273 | } |
274 | } | |
7b53b5a7 | 275 | for (let step of V.steps[V.ROOK].concat(V.steps[V.BISHOP])) { |
b2655276 BA |
276 | let [i, j] = [x + step[0], y + step[1]]; |
277 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { | |
278 | i += step[0]; | |
279 | j += step[1]; | |
280 | } | |
281 | if ( | |
282 | V.OnBoard(i, j) && | |
283 | this.board[i][j] != V.EMPTY && | |
284 | this.getColor(i, j) == color | |
285 | ) { | |
286 | const deltaX = Math.abs(i - x); | |
287 | const deltaY = Math.abs(j - y); | |
b2655276 BA |
288 | switch (this.getPiece(i, j)) { |
289 | case V.PAWN: | |
ad1e629e BA |
290 | if ( |
291 | (x - i) / deltaX == pawnShift && | |
292 | deltaX <= 2 && | |
293 | deltaY <= 1 | |
294 | ) { | |
81e74ee5 | 295 | if (sqCol == color && deltaY == 0) { |
b2655276 BA |
296 | // Pushed forward |
297 | const maxSteps = (i == pawnStartRank && deltaX == 1 ? 2 : 1); | |
298 | addMoves(step, maxSteps); | |
299 | } | |
81e74ee5 | 300 | else if (sqCol != color && deltaY == 1 && deltaX == 1) |
b2655276 BA |
301 | // Pushed diagonally |
302 | addMoves(step, 1); | |
303 | } | |
304 | break; | |
305 | case V.ROOK: | |
306 | if (deltaX == 0 || deltaY == 0) addMoves(step); | |
307 | break; | |
b2655276 BA |
308 | case V.BISHOP: |
309 | if (deltaX == deltaY) addMoves(step); | |
310 | break; | |
311 | case V.QUEEN: | |
cfceecba BA |
312 | // All steps are valid for a queen: |
313 | addMoves(step); | |
b2655276 BA |
314 | break; |
315 | case V.KING: | |
316 | if (deltaX <= 1 && deltaY <= 1) addMoves(step, 1); | |
317 | break; | |
318 | } | |
319 | } | |
320 | } | |
321 | return moves; | |
b866a62a | 322 | } |
93ce6119 | 323 | // If subTurn == 2 then we should have a first move, |
b2655276 BA |
324 | // which restrict what we can play now: only in the first move direction |
325 | // NOTE: no need for knight or pawn checks, because the move will be | |
326 | // naturally limited in those cases. | |
93ce6119 BA |
327 | const L = this.firstMove.length; |
328 | const fm = this.firstMove[L-1]; | |
81e74ee5 BA |
329 | if ( |
330 | (fm.appear.length == 2 && fm.vanish.length == 2) || | |
331 | (fm.vanish[0].c == sqCol && sqCol != color) | |
332 | ) { | |
333 | // Castle or again opponent color: no move playable then. | |
b2655276 | 334 | return []; |
81e74ee5 | 335 | } |
b2655276 BA |
336 | if (fm.appear.length == 0) { |
337 | // Piece at subTurn 1 just exited the board. | |
338 | // Can I be a piece which caused the exit? | |
ad1e629e | 339 | if ( |
6e0c0bcb BA |
340 | // Only "turn" color can do actions |
341 | sqCol == color && | |
ad1e629e BA |
342 | this.isAprioriValidExit( |
343 | [x, y], | |
344 | [fm.start.x, fm.start.y], | |
345 | fm.vanish[0].c | |
346 | ) | |
347 | ) { | |
b2655276 BA |
348 | // Seems so: |
349 | const dir = this.getNormalizedDirection( | |
350 | [fm.start.x - x, fm.start.y - y]); | |
6e0c0bcb BA |
351 | const nbSteps = |
352 | ([V.PAWN,V.KING,V.KNIGHT].includes(this.getPiece(x, y)) ? 1 : null); | |
353 | return this.getMovesInDirection([x, y], dir, nbSteps); | |
b2655276 | 354 | } |
93ce6119 BA |
355 | } |
356 | else { | |
b2655276 BA |
357 | const dirM = this.getNormalizedDirection( |
358 | [fm.end.x - fm.start.x, fm.end.y - fm.start.y]); | |
359 | const dir = this.getNormalizedDirection( | |
360 | [fm.start.x - x, fm.start.y - y]); | |
ad1e629e BA |
361 | // Normalized directions should match |
362 | if (dir[0] == dirM[0] && dir[1] == dirM[1]) { | |
05d37cc7 BA |
363 | // If first move is a pawn move, only a queen, rook, or maybe king or |
364 | // pawn can follow (need vertical movement option). | |
365 | if ( | |
366 | fm.vanish[0].p == V.PAWN && | |
367 | fm.vanish[0].c == color && | |
368 | !this.isAprioriValidVertical([x, y], fm.start.x) | |
369 | ) { | |
370 | return []; | |
371 | } | |
ad1e629e BA |
372 | // And nothing should stand between [x, y] and the square fm.start |
373 | let [i, j] = [x + dir[0], y + dir[1]]; | |
374 | while ( | |
375 | (i != fm.start.x || j != fm.start.y) && | |
376 | this.board[i][j] == V.EMPTY | |
377 | ) { | |
378 | i += dir[0]; | |
379 | j += dir[1]; | |
380 | } | |
381 | if (i == fm.start.x && j == fm.start.y) | |
382 | return this.getMovesInDirection([x, y], dir); | |
383 | } | |
93ce6119 | 384 | } |
b2655276 | 385 | return []; |
61656127 BA |
386 | } |
387 | ||
cfceecba BA |
388 | getSlideNJumpMoves([x, y], steps, oneStep) { |
389 | let moves = []; | |
81e74ee5 BA |
390 | const c = this.getColor(x, y); |
391 | const piece = this.getPiece(x, y); | |
cfceecba BA |
392 | outerLoop: for (let step of steps) { |
393 | let i = x + step[0]; | |
394 | let j = y + step[1]; | |
395 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { | |
396 | moves.push(this.getBasicMove([x, y], [i, j])); | |
397 | if (oneStep) continue outerLoop; | |
398 | i += step[0]; | |
399 | j += step[1]; | |
400 | } | |
401 | if (V.OnBoard(i, j)) { | |
402 | if (this.canTake([x, y], [i, j])) | |
403 | moves.push(this.getBasicMove([x, y], [i, j])); | |
404 | } | |
405 | else { | |
406 | // Add potential board exit (suicide), except for the king | |
cfceecba | 407 | if (piece != V.KING) { |
cfceecba BA |
408 | moves.push({ |
409 | start: { x: x, y: y}, | |
410 | end: { x: this.kingPos[c][0], y: this.kingPos[c][1] }, | |
411 | appear: [], | |
412 | vanish: [ | |
413 | new PiPo({ | |
414 | x: x, | |
415 | y: y, | |
416 | c: c, | |
417 | p: piece | |
418 | }) | |
419 | ] | |
420 | }); | |
421 | } | |
422 | } | |
423 | } | |
424 | return moves; | |
425 | } | |
426 | ||
61656127 BA |
427 | // Does m2 un-do m1 ? (to disallow undoing actions) |
428 | oppositeMoves(m1, m2) { | |
429 | const isEqual = (av1, av2) => { | |
430 | // Precondition: av1 and av2 length = 2 | |
431 | for (let av of av1) { | |
432 | const avInAv2 = av2.find(elt => { | |
433 | return ( | |
434 | elt.x == av.x && | |
435 | elt.y == av.y && | |
436 | elt.c == av.c && | |
437 | elt.p == av.p | |
438 | ); | |
439 | }); | |
440 | if (!avInAv2) return false; | |
441 | } | |
442 | return true; | |
443 | }; | |
444 | return ( | |
61656127 BA |
445 | m1.appear.length == 2 && |
446 | m2.appear.length == 2 && | |
447 | m1.vanish.length == 2 && | |
448 | m2.vanish.length == 2 && | |
449 | isEqual(m1.appear, m2.vanish) && | |
450 | isEqual(m1.vanish, m2.appear) | |
451 | ); | |
452 | } | |
453 | ||
93ce6119 BA |
454 | getAmove(move1, move2) { |
455 | // Just merge (one is action one is move, one may be empty) | |
456 | return { | |
457 | appear: move1.appear.concat(move2.appear), | |
458 | vanish: move1.vanish.concat(move2.vanish) | |
459 | } | |
460 | } | |
461 | ||
61656127 | 462 | filterValid(moves) { |
93ce6119 BA |
463 | const color = this.turn; |
464 | if (this.subTurn == 1) { | |
465 | return moves.filter(m => { | |
466 | // A move is valid either if it doesn't result in a check, | |
467 | // or if a second move is possible to counter the check | |
468 | // (not undoing a potential move + action of the opponent) | |
469 | this.play(m); | |
470 | let res = this.underCheck(color); | |
471 | if (res) { | |
472 | const moves2 = this.getAllPotentialMoves(); | |
ad1e629e | 473 | for (let m2 of moves2) { |
93ce6119 BA |
474 | this.play(m2); |
475 | const res2 = this.underCheck(color); | |
476 | this.undo(m2); | |
477 | if (!res2) { | |
478 | res = false; | |
479 | break; | |
480 | } | |
481 | } | |
482 | } | |
483 | this.undo(m); | |
484 | return !res; | |
485 | }); | |
486 | } | |
487 | const Lf = this.firstMove.length; | |
488 | const La = this.amoves.length; | |
489 | if (La == 0) return super.filterValid(moves); | |
a443d256 | 490 | return ( |
93ce6119 | 491 | super.filterValid( |
a443d256 BA |
492 | moves.filter(m => { |
493 | // Move shouldn't undo another: | |
93ce6119 BA |
494 | const amove = this.getAmove(this.firstMove[Lf-1], m); |
495 | return !this.oppositeMoves(this.amoves[La-1], amove); | |
a443d256 BA |
496 | }) |
497 | ) | |
498 | ); | |
b866a62a BA |
499 | } |
500 | ||
c7550017 BA |
501 | isAttackedBySlideNJump([x, y], color, piece, steps, oneStep) { |
502 | for (let step of steps) { | |
503 | let rx = x + step[0], | |
504 | ry = y + step[1]; | |
505 | while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) { | |
506 | rx += step[0]; | |
507 | ry += step[1]; | |
508 | } | |
509 | if ( | |
510 | V.OnBoard(rx, ry) && | |
511 | this.getPiece(rx, ry) == piece && | |
512 | this.getColor(rx, ry) == color | |
513 | ) { | |
8c267d0c BA |
514 | // Continue some steps in the same direction (pull) |
515 | rx += step[0]; | |
516 | ry += step[1]; | |
517 | while ( | |
518 | V.OnBoard(rx, ry) && | |
519 | this.board[rx][ry] == V.EMPTY && | |
520 | !oneStep | |
521 | ) { | |
522 | rx += step[0]; | |
523 | ry += step[1]; | |
524 | } | |
525 | if (!V.OnBoard(rx, ry)) return true; | |
526 | // Step in the other direction (push) | |
c7550017 BA |
527 | rx = x - step[0]; |
528 | ry = y - step[1]; | |
2c5d7b20 BA |
529 | while ( |
530 | V.OnBoard(rx, ry) && | |
531 | this.board[rx][ry] == V.EMPTY && | |
532 | !oneStep | |
533 | ) { | |
c7550017 BA |
534 | rx -= step[0]; |
535 | ry -= step[1]; | |
536 | } | |
537 | if (!V.OnBoard(rx, ry)) return true; | |
538 | } | |
539 | } | |
540 | return false; | |
541 | } | |
542 | ||
543 | isAttackedByPawn([x, y], color) { | |
544 | const lastRank = (color == 'w' ? 0 : 7); | |
ad1e629e | 545 | if (x != lastRank) |
c7550017 BA |
546 | // The king can be pushed out by a pawn only on last rank |
547 | return false; | |
548 | const pawnShift = (color == "w" ? 1 : -1); | |
549 | for (let i of [-1, 1]) { | |
550 | if ( | |
551 | y + i >= 0 && | |
552 | y + i < V.size.y && | |
553 | this.getPiece(x + pawnShift, y + i) == V.PAWN && | |
554 | this.getColor(x + pawnShift, y + i) == color | |
555 | ) { | |
556 | return true; | |
557 | } | |
558 | } | |
559 | return false; | |
560 | } | |
61656127 | 561 | |
156986e6 BA |
562 | // No consideration of color: all pieces could be played |
563 | getAllPotentialMoves() { | |
564 | let potentialMoves = []; | |
565 | for (let i = 0; i < V.size.x; i++) { | |
566 | for (let j = 0; j < V.size.y; j++) { | |
567 | if (this.board[i][j] != V.EMPTY) { | |
568 | Array.prototype.push.apply( | |
569 | potentialMoves, | |
570 | this.getPotentialMovesFrom([i, j]) | |
571 | ); | |
572 | } | |
573 | } | |
574 | } | |
575 | return potentialMoves; | |
576 | } | |
577 | ||
61656127 BA |
578 | getCurrentScore() { |
579 | if (this.subTurn == 2) | |
580 | // Move not over | |
581 | return "*"; | |
582 | return super.getCurrentScore(); | |
583 | } | |
584 | ||
93ce6119 | 585 | doClick(square) { |
b2655276 BA |
586 | // If subTurn == 2 && square is empty && !underCheck, |
587 | // then return an empty move, allowing to "pass" subTurn2 | |
93ce6119 BA |
588 | if ( |
589 | this.subTurn == 2 && | |
7b53b5a7 | 590 | this.board[square[0]][square[1]] == V.EMPTY && |
b2655276 | 591 | !this.underCheck(this.turn) |
93ce6119 BA |
592 | ) { |
593 | return { | |
7b53b5a7 BA |
594 | start: { x: -1, y: -1 }, |
595 | end: { x: -1, y: -1 }, | |
93ce6119 BA |
596 | appear: [], |
597 | vanish: [] | |
598 | }; | |
599 | } | |
600 | return null; | |
601 | } | |
602 | ||
61656127 BA |
603 | play(move) { |
604 | move.flags = JSON.stringify(this.aggregateFlags()); | |
605 | V.PlayOnBoard(this.board, move); | |
7ddfec38 | 606 | if (this.subTurn == 2) { |
7b53b5a7 BA |
607 | const L = this.firstMove.length; |
608 | this.amoves.push(this.getAmove(this.firstMove[L-1], move)); | |
61656127 | 609 | this.turn = V.GetOppCol(this.turn); |
7ddfec38 | 610 | this.movesCount++; |
61656127 | 611 | } |
a443d256 | 612 | else this.firstMove.push(move); |
7ddfec38 | 613 | this.subTurn = 3 - this.subTurn; |
61656127 BA |
614 | this.postPlay(move); |
615 | } | |
616 | ||
7b53b5a7 BA |
617 | postPlay(move) { |
618 | if (move.start.x < 0) return; | |
619 | for (let a of move.appear) | |
620 | if (a.p == V.KING) this.kingPos[a.c] = [a.x, a.y]; | |
621 | this.updateCastleFlags(move); | |
622 | } | |
623 | ||
624 | updateCastleFlags(move) { | |
625 | const firstRank = { 'w': V.size.x - 1, 'b': 0 }; | |
7ddfec38 | 626 | for (let v of move.vanish) { |
7b53b5a7 BA |
627 | if (v.p == V.KING) this.castleFlags[v.c] = [V.size.y, V.size.y]; |
628 | else if (v.x == firstRank[v.c] && this.castleFlags[v.c].includes(v.y)) { | |
629 | const flagIdx = (v.y == this.castleFlags[v.c][0] ? 0 : 1); | |
630 | this.castleFlags[v.c][flagIdx] = V.size.y; | |
7ddfec38 | 631 | } |
61656127 BA |
632 | } |
633 | } | |
634 | ||
635 | undo(move) { | |
636 | this.disaggregateFlags(JSON.parse(move.flags)); | |
637 | V.UndoOnBoard(this.board, move); | |
7ddfec38 | 638 | if (this.subTurn == 1) { |
61656127 | 639 | this.turn = V.GetOppCol(this.turn); |
7ddfec38 | 640 | this.movesCount--; |
61656127 | 641 | } |
a443d256 | 642 | else this.firstMove.pop(); |
7ddfec38 | 643 | this.subTurn = 3 - this.subTurn; |
61656127 BA |
644 | this.postUndo(move); |
645 | } | |
7b53b5a7 BA |
646 | |
647 | postUndo(move) { | |
648 | // (Potentially) Reset king position | |
649 | for (let v of move.vanish) | |
650 | if (v.p == V.KING) this.kingPos[v.c] = [v.x, v.y]; | |
651 | } | |
652 | ||
ad1e629e BA |
653 | getComputerMove() { |
654 | let moves = this.getAllValidMoves(); | |
655 | if (moves.length == 0) return null; | |
656 | // "Search" at depth 1 for now | |
657 | const maxeval = V.INFINITY; | |
658 | const color = this.turn; | |
659 | const emptyMove = { | |
660 | start: { x: -1, y: -1 }, | |
661 | end: { x: -1, y: -1 }, | |
662 | appear: [], | |
663 | vanish: [] | |
664 | }; | |
665 | moves.forEach(m => { | |
666 | this.play(m); | |
667 | m.eval = (color == "w" ? -1 : 1) * maxeval; | |
668 | const moves2 = this.getAllValidMoves().concat([emptyMove]); | |
669 | m.next = moves2[0]; | |
670 | moves2.forEach(m2 => { | |
671 | this.play(m2); | |
672 | const score = this.getCurrentScore(); | |
673 | let mvEval = 0; | |
674 | if (score != "1/2") { | |
675 | if (score != "*") mvEval = (score == "1-0" ? 1 : -1) * maxeval; | |
676 | else mvEval = this.evalPosition(); | |
677 | } | |
678 | if ( | |
679 | (color == 'w' && mvEval > m.eval) || | |
680 | (color == 'b' && mvEval < m.eval) | |
681 | ) { | |
682 | m.eval = mvEval; | |
683 | m.next = m2; | |
684 | } | |
685 | this.undo(m2); | |
686 | }); | |
687 | this.undo(m); | |
688 | }); | |
689 | moves.sort((a, b) => { | |
690 | return (color == "w" ? 1 : -1) * (b.eval - a.eval); | |
691 | }); | |
692 | let candidates = [0]; | |
693 | for (let i = 1; i < moves.length && moves[i].eval == moves[0].eval; i++) | |
694 | candidates.push(i); | |
695 | const mIdx = candidates[randInt(candidates.length)]; | |
696 | const move2 = moves[mIdx].next; | |
697 | delete moves[mIdx]["next"]; | |
698 | return [moves[mIdx], move2]; | |
699 | } | |
700 | ||
7b53b5a7 BA |
701 | getNotation(move) { |
702 | if (move.start.x < 0) | |
703 | // A second move is always required, but may be empty | |
704 | return "-"; | |
705 | const initialSquare = V.CoordsToSquare(move.start); | |
706 | const finalSquare = V.CoordsToSquare(move.end); | |
707 | if (move.appear.length == 0) | |
708 | // Pushed or pulled out of the board | |
709 | return initialSquare + "R"; | |
710 | return move.appear[0].p.toUpperCase() + initialSquare + finalSquare; | |
711 | } | |
0d5335de | 712 | }; |