Fix Cwda (track kings)
[vchess.git] / client / src / variants / Wildebeest.js
... / ...
CommitLineData
1import { ChessRules, Move, PiPo } from "@/base_rules";
2import { ArrayFun } from "@/utils/array";
3import { sample, randInt } from "@/utils/alea";
4
5export class WildebeestRules extends ChessRules {
6
7 static get size() {
8 return { x: 10, y: 11 };
9 }
10
11 static get CAMEL() {
12 return "c";
13 }
14 static get WILDEBEEST() {
15 return "w";
16 }
17
18 static get PIECES() {
19 return ChessRules.PIECES.concat([V.CAMEL, V.WILDEBEEST]);
20 }
21
22 static get steps() {
23 return Object.assign(
24 {},
25 ChessRules.steps,
26 // Add camel moves:
27 {
28 c: [
29 [-3, -1],
30 [-3, 1],
31 [-1, -3],
32 [-1, 3],
33 [1, -3],
34 [1, 3],
35 [3, -1],
36 [3, 1]
37 ]
38 }
39 );
40 }
41
42 static IsGoodEnpassant(enpassant) {
43 if (enpassant != "-") return !!enpassant.match(/^([a-j][0-9]{1,2},?)+$/);
44 return true;
45 }
46
47 getPpath(b) {
48 return ([V.CAMEL, V.WILDEBEEST].includes(b[1]) ? "Wildebeest/" : "") + b;
49 }
50
51 // There may be 2 enPassant squares (if pawn jump 3 squares)
52 getEnpassantFen() {
53 const L = this.epSquares.length;
54 if (!this.epSquares[L - 1]) return "-"; //no en-passant
55 let res = "";
56 this.epSquares[L - 1].forEach(sq => {
57 res += V.CoordsToSquare(sq) + ",";
58 });
59 return res.slice(0, -1); //remove last comma
60 }
61
62 // En-passant after 2-sq or 3-sq jumps
63 getEpSquare(moveOrSquare) {
64 if (!moveOrSquare) return undefined;
65 if (typeof moveOrSquare === "string") {
66 const square = moveOrSquare;
67 if (square == "-") return undefined;
68 let res = [];
69 square.split(",").forEach(sq => {
70 res.push(V.SquareToCoords(sq));
71 });
72 return res;
73 }
74 // Argument is a move:
75 const move = moveOrSquare;
76 const [sx, sy, ex] = [move.start.x, move.start.y, move.end.x];
77 if (this.getPiece(sx, sy) == V.PAWN && Math.abs(sx - ex) >= 2) {
78 const step = (ex - sx) / Math.abs(ex - sx);
79 let res = [
80 {
81 x: sx + step,
82 y: sy
83 }
84 ];
85 if (sx + 2 * step != ex) {
86 // 3-squares move
87 res.push({
88 x: sx + 2 * step,
89 y: sy
90 });
91 }
92 return res;
93 }
94 return undefined; //default
95 }
96
97 getPotentialMovesFrom([x, y]) {
98 switch (this.getPiece(x, y)) {
99 case V.CAMEL:
100 return this.getPotentialCamelMoves([x, y]);
101 case V.WILDEBEEST:
102 return this.getPotentialWildebeestMoves([x, y]);
103 default:
104 return super.getPotentialMovesFrom([x, y]);
105 }
106 }
107
108 // Pawns jump 2 or 3 squares, and promote to queen or wildebeest
109 getPotentialPawnMoves([x, y]) {
110 const color = this.turn;
111 let moves = [];
112 const [sizeX, sizeY] = [V.size.x, V.size.y];
113 const shiftX = color == "w" ? -1 : 1;
114 const startRanks = color == "w" ? [sizeX - 2, sizeX - 3] : [1, 2];
115 const lastRanks = color == "w" ? [0, 1] : [sizeX - 1, sizeX -2];
116 let finalPieces = [V.PAWN];
117 if (x + shiftX == lastRanks[1])
118 Array.prototype.push.apply(finalPieces, [V.WILDEBEEST, V.QUEEN]);
119 else if (x + shiftX == lastRanks[0])
120 finalPieces = [V.WILDEBEEST, V.QUEEN];
121
122 if (this.board[x + shiftX][y] == V.EMPTY) {
123 // One square forward
124 for (let piece of finalPieces)
125 moves.push(
126 this.getBasicMove([x, y], [x + shiftX, y], { c: color, p: piece })
127 );
128 if (startRanks.includes(x)) {
129 if (this.board[x + 2 * shiftX][y] == V.EMPTY) {
130 // Two squares jump
131 moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y]));
132 if (x == startRanks[0] && this.board[x + 3 * shiftX][y] == V.EMPTY) {
133 // Three squares jump
134 moves.push(this.getBasicMove([x, y], [x + 3 * shiftX, y]));
135 }
136 }
137 }
138 }
139 // Captures
140 for (let shiftY of [-1, 1]) {
141 if (
142 y + shiftY >= 0 &&
143 y + shiftY < sizeY &&
144 this.board[x + shiftX][y + shiftY] != V.EMPTY &&
145 this.canTake([x, y], [x + shiftX, y + shiftY])
146 ) {
147 for (let piece of finalPieces) {
148 moves.push(
149 this.getBasicMove([x, y], [x + shiftX, y + shiftY], {
150 c: color,
151 p: piece
152 })
153 );
154 }
155 }
156 }
157
158 // En passant
159 const Lep = this.epSquares.length;
160 const epSquare = this.epSquares[Lep - 1];
161 if (!!epSquare) {
162 for (let epsq of epSquare) {
163 // TODO: some redundant checks
164 if (epsq.x == x + shiftX && Math.abs(epsq.y - y) == 1) {
165 let enpassantMove = this.getBasicMove([x, y], [epsq.x, epsq.y]);
166 // WARNING: the captured pawn may be diagonally behind us,
167 // if it's a 3-squares jump and we take on 1st passing square
168 const px = this.board[x][epsq.y] != V.EMPTY ? x : x - shiftX;
169 enpassantMove.vanish.push({
170 x: px,
171 y: epsq.y,
172 p: "p",
173 c: this.getColor(px, epsq.y)
174 });
175 moves.push(enpassantMove);
176 }
177 }
178 }
179
180 return moves;
181 }
182
183 getPotentialCamelMoves(sq) {
184 return this.getSlideNJumpMoves(sq, V.steps[V.CAMEL], 1);
185 }
186
187 getPotentialWildebeestMoves(sq) {
188 return this.getSlideNJumpMoves(
189 sq, V.steps[V.KNIGHT].concat(V.steps[V.CAMEL]), 1);
190 }
191
192 getPPpath(m) {
193 if (
194 m.appear.length == 2 && m.vanish.length == 2 &&
195 Math.abs(m.end.y - m.start.y) == 1 &&
196 this.board[m.end.x][m.end.y] == V.EMPTY
197 ) {
198 // Castle, king moved by one square only, not directly onto rook
199 return "Wildebeest/castle";
200 }
201 return super.getPPpath(m);
202 }
203
204 // Special Wildebeest castling rules:
205 getCastleMoves([x, y]) {
206 const c = this.getColor(x, y);
207 const oppCol = V.GetOppCol(c);
208 let moves = [];
209 let i = 0;
210 const castlingKing = this.board[x][y].charAt(1);
211 castlingCheck: for (
212 let castleSide = 0;
213 castleSide < 2;
214 castleSide++ //"large", then "small"
215 ) {
216 if (this.castleFlags[c][castleSide] >= V.size.y) continue;
217 // Rook and king are on initial position
218 const rookPos = this.castleFlags[c][castleSide];
219 const range = (castleSide == 0 ? [rookPos, y] : [y, rookPos]);
220
221 // King and rook must be connected:
222 for (let i = range[0] + 1; i <= range[1] - 1; i++) {
223 if (this.board[x][i] != V.EMPTY) continue castlingCheck;
224 }
225 const step = 2 * castleSide - 1;
226 // No attacks on the path of the king ?
227 for (let i = range[0]; i <= range[1]; i++) {
228 if (i != rookPos && this.isAttacked([x, i], oppCol))
229 continue castlingCheck;
230 if (
231 i != y &&
232 // Do not end in the corner, except if starting square is too near
233 (i > 0 || y == 1) &&
234 (i < V.size.y - 1 || y == V.size.y - 2)
235 ) {
236 // Found a possible castle move:
237 moves.push(
238 new Move({
239 appear: [
240 new PiPo({
241 x: x,
242 y: i,
243 p: V.KING,
244 c: c
245 }),
246 new PiPo({
247 x: x,
248 y: i - step,
249 p: V.ROOK,
250 c: c
251 })
252 ],
253 vanish: [
254 new PiPo({ x: x, y: y, p: V.KING, c: c }),
255 new PiPo({ x: x, y: rookPos, p: V.ROOK, c: c })
256 ]
257 })
258 );
259 }
260 }
261 }
262
263 return moves;
264 }
265
266 isAttacked(sq, color) {
267 return (
268 super.isAttacked(sq, color) ||
269 this.isAttackedByCamel(sq, color) ||
270 this.isAttackedByWildebeest(sq, color)
271 );
272 }
273
274 isAttackedByCamel(sq, color) {
275 return this.isAttackedBySlideNJump(
276 sq, color, V.CAMEL, V.steps[V.CAMEL], 1);
277 }
278
279 isAttackedByWildebeest(sq, color) {
280 return this.isAttackedBySlideNJump(
281 sq, color, V.WILDEBEEST, V.steps[V.KNIGHT].concat(V.steps[V.CAMEL]), 1);
282 }
283
284 getCurrentScore() {
285 if (this.atLeastOneMove()) return "*";
286 // No valid move: game is lost (stalemate is a win)
287 return this.turn == "w" ? "0-1" : "1-0";
288 }
289
290 static get VALUES() {
291 return Object.assign(
292 { c: 3, w: 7 }, //experimental
293 ChessRules.VALUES
294 );
295 }
296
297 static get SEARCH_DEPTH() {
298 return 2;
299 }
300
301 static GenRandInitFen(options) {
302 if (options.randomness == 0) {
303 return (
304 "rnccwkqbbnr/ppppppppppp/92/92/92/92/92/92/PPPPPPPPPPP/RNBBQKWCCNR " +
305 "w 0 akak -"
306 );
307 }
308
309 let pieces = { w: new Array(11), b: new Array(11) };
310 let flags = "";
311 for (let c of ["w", "b"]) {
312 if (c == 'b' && options.randomness == 1) {
313 pieces['b'] = pieces['w'];
314 flags += flags;
315 break;
316 }
317
318 let positions = ArrayFun.range(11);
319
320 // Get random squares for bishops + camels (different colors)
321 let randIndexes = sample(ArrayFun.range(6), 2).map(i => {
322 return 2 * i;
323 });
324 let bishop1Pos = positions[randIndexes[0]];
325 let camel1Pos = positions[randIndexes[1]];
326 // The second bishop (camel) must be on a square of different color
327 let randIndexes_tmp = sample(ArrayFun.range(5), 2).map(i => {
328 return 2 * i + 1;
329 });
330 let bishop2Pos = positions[randIndexes_tmp[0]];
331 let camel2Pos = positions[randIndexes_tmp[1]];
332 for (let idx of randIndexes.concat(randIndexes_tmp).sort((a, b) => {
333 return b - a;
334 })) {
335 // Largest indices first
336 positions.splice(idx, 1);
337 }
338
339 let randIndex = randInt(7);
340 let knight1Pos = positions[randIndex];
341 positions.splice(randIndex, 1);
342 randIndex = randInt(6);
343 let knight2Pos = positions[randIndex];
344 positions.splice(randIndex, 1);
345
346 randIndex = randInt(5);
347 let queenPos = positions[randIndex];
348 positions.splice(randIndex, 1);
349
350 // Random square for wildebeest
351 randIndex = randInt(4);
352 let wildebeestPos = positions[randIndex];
353 positions.splice(randIndex, 1);
354
355 let rook1Pos = positions[0];
356 let kingPos = positions[1];
357 let rook2Pos = positions[2];
358
359 pieces[c][rook1Pos] = "r";
360 pieces[c][knight1Pos] = "n";
361 pieces[c][bishop1Pos] = "b";
362 pieces[c][queenPos] = "q";
363 pieces[c][camel1Pos] = "c";
364 pieces[c][camel2Pos] = "c";
365 pieces[c][wildebeestPos] = "w";
366 pieces[c][kingPos] = "k";
367 pieces[c][bishop2Pos] = "b";
368 pieces[c][knight2Pos] = "n";
369 pieces[c][rook2Pos] = "r";
370 flags += V.CoordToColumn(rook1Pos) + V.CoordToColumn(rook2Pos);
371 }
372 return (
373 pieces["b"].join("") +
374 "/ppppppppppp/92/92/92/92/92/92/PPPPPPPPPPP/" +
375 pieces["w"].join("").toUpperCase() +
376 " w 0 " + flags + " -"
377 );
378 }
379
380};