| 1 | import { ChessRules } from "@/base_rules"; |
| 2 | import { randInt } from "@/utils/alea"; |
| 3 | |
| 4 | export class ApocalypseRules extends ChessRules { |
| 5 | static get PawnSpecs() { |
| 6 | return Object.assign( |
| 7 | {}, |
| 8 | ChessRules.PawnSpecs, |
| 9 | { |
| 10 | twoSquares: false, |
| 11 | promotions: [V.KNIGHT] |
| 12 | } |
| 13 | ); |
| 14 | } |
| 15 | |
| 16 | static get HasCastle() { |
| 17 | return false; |
| 18 | } |
| 19 | |
| 20 | static get HasEnpassant() { |
| 21 | return false; |
| 22 | } |
| 23 | |
| 24 | static get CanAnalyze() { |
| 25 | return false; |
| 26 | } |
| 27 | |
| 28 | static get ShowMoves() { |
| 29 | return "byrow"; |
| 30 | } |
| 31 | |
| 32 | static get PIECES() { |
| 33 | return [V.PAWN, V.KNIGHT]; |
| 34 | } |
| 35 | |
| 36 | static IsGoodPosition(position) { |
| 37 | if (position.length == 0) return false; |
| 38 | const rows = position.split("/"); |
| 39 | if (rows.length != V.size.x) return false; |
| 40 | // At least one pawn per color |
| 41 | let pawns = { "p": 0, "P": 0 }; |
| 42 | for (let row of rows) { |
| 43 | let sumElts = 0; |
| 44 | for (let i = 0; i < row.length; i++) { |
| 45 | if (['P','p'].includes(row[i])) pawns[row[i]]++; |
| 46 | if (V.PIECES.includes(row[i].toLowerCase())) sumElts++; |
| 47 | else { |
| 48 | const num = parseInt(row[i]); |
| 49 | if (isNaN(num)) return false; |
| 50 | sumElts += num; |
| 51 | } |
| 52 | } |
| 53 | if (sumElts != V.size.y) return false; |
| 54 | } |
| 55 | if (Object.values(pawns).some(v => v == 0)) |
| 56 | return false; |
| 57 | return true; |
| 58 | } |
| 59 | |
| 60 | static IsGoodFen(fen) { |
| 61 | if (!ChessRules.IsGoodFen(fen)) return false; |
| 62 | const fenParsed = V.ParseFen(fen); |
| 63 | // 4) Check whiteMove |
| 64 | if ( |
| 65 | ( |
| 66 | fenParsed.turn == "w" && |
| 67 | // NOTE: do not check really JSON stringified move... |
| 68 | (!fenParsed.whiteMove || fenParsed.whiteMove == "-") |
| 69 | ) |
| 70 | || |
| 71 | (fenParsed.turn == "b" && fenParsed.whiteMove != "-") |
| 72 | ) { |
| 73 | return false; |
| 74 | } |
| 75 | return true; |
| 76 | } |
| 77 | |
| 78 | static IsGoodFlags(flags) { |
| 79 | return !!flags.match(/^[0-2]{2,2}$/); |
| 80 | } |
| 81 | |
| 82 | aggregateFlags() { |
| 83 | return this.penaltyFlags; |
| 84 | } |
| 85 | |
| 86 | disaggregateFlags(flags) { |
| 87 | this.penaltyFlags = flags; |
| 88 | } |
| 89 | |
| 90 | static ParseFen(fen) { |
| 91 | const fenParts = fen.split(" "); |
| 92 | return Object.assign( |
| 93 | ChessRules.ParseFen(fen), |
| 94 | { whiteMove: fenParts[4] } |
| 95 | ); |
| 96 | } |
| 97 | |
| 98 | static get size() { |
| 99 | return { x: 5, y: 5 }; |
| 100 | } |
| 101 | |
| 102 | static GenRandInitFen() { |
| 103 | return "npppn/p3p/5/P3P/NPPPN w 0 00 -"; |
| 104 | } |
| 105 | |
| 106 | getFen() { |
| 107 | return super.getFen() + " " + this.getWhitemoveFen(); |
| 108 | } |
| 109 | |
| 110 | getFenForRepeat() { |
| 111 | return super.getFenForRepeat() + "_" + this.getWhitemoveFen(); |
| 112 | } |
| 113 | |
| 114 | getFlagsFen() { |
| 115 | return this.penaltyFlags.join(""); |
| 116 | } |
| 117 | |
| 118 | setOtherVariables(fen) { |
| 119 | const parsedFen = V.ParseFen(fen); |
| 120 | this.setFlags(parsedFen.flags); |
| 121 | // Also init whiteMove |
| 122 | this.whiteMove = |
| 123 | parsedFen.whiteMove != "-" |
| 124 | ? JSON.parse(parsedFen.whiteMove) |
| 125 | : null; |
| 126 | } |
| 127 | |
| 128 | setFlags(fenflags) { |
| 129 | this.penaltyFlags = [0, 1].map(i => parseInt(fenflags[i])); |
| 130 | } |
| 131 | |
| 132 | getWhitemoveFen() { |
| 133 | if (!this.whiteMove) return "-"; |
| 134 | return JSON.stringify({ |
| 135 | start: this.whiteMove.start, |
| 136 | end: this.whiteMove.end, |
| 137 | appear: this.whiteMove.appear, |
| 138 | vanish: this.whiteMove.vanish |
| 139 | }); |
| 140 | } |
| 141 | |
| 142 | getSpeculations(moves, sq) { |
| 143 | let moveSet = {}; |
| 144 | moves.forEach(m => { |
| 145 | const mHash = "m" + m.start.x + m.start.y + m.end.x + m.end.y; |
| 146 | moveSet[mHash] = true; |
| 147 | }); |
| 148 | const color = this.turn; |
| 149 | this.turn = V.GetOppCol(color); |
| 150 | const oppMoves = super.getAllValidMoves(); |
| 151 | this.turn = color; |
| 152 | // For each opponent's move, generate valid moves [from sq] |
| 153 | let speculations = []; |
| 154 | oppMoves.forEach(m => { |
| 155 | V.PlayOnBoard(this.board, m); |
| 156 | const newValidMoves = |
| 157 | !!sq |
| 158 | ? super.getPotentialMovesFrom(sq) |
| 159 | : super.getAllValidMoves(); |
| 160 | newValidMoves.forEach(vm => { |
| 161 | const mHash = "m" + vm.start.x + vm.start.y + vm.end.x + vm.end.y; |
| 162 | if (!moveSet[mHash]) { |
| 163 | moveSet[mHash] = true; |
| 164 | vm.illegal = true; //potentially illegal! |
| 165 | speculations.push(vm); |
| 166 | } |
| 167 | }); |
| 168 | V.UndoOnBoard(this.board, m); |
| 169 | }); |
| 170 | return speculations; |
| 171 | } |
| 172 | |
| 173 | getPossibleMovesFrom([x, y]) { |
| 174 | const possibleMoves = super.getPotentialMovesFrom([x, y]) |
| 175 | // Augment potential moves with opponent's moves speculation: |
| 176 | return possibleMoves.concat(this.getSpeculations(possibleMoves, [x, y])); |
| 177 | } |
| 178 | |
| 179 | getAllValidMoves() { |
| 180 | // Return possible moves + potentially valid moves |
| 181 | const validMoves = super.getAllValidMoves(); |
| 182 | return validMoves.concat(this.getSpeculations(validMoves)); |
| 183 | } |
| 184 | |
| 185 | addPawnMoves([x1, y1], [x2, y2], moves) { |
| 186 | let finalPieces = [V.PAWN]; |
| 187 | const color = this.turn; |
| 188 | const lastRank = (color == "w" ? 0 : V.size.x - 1); |
| 189 | if (x2 == lastRank) { |
| 190 | // If 0 or 1 horsemen, promote in knight |
| 191 | let knightCounter = 0; |
| 192 | let emptySquares = []; |
| 193 | for (let i=0; i<V.size.x; i++) { |
| 194 | for (let j=0; j<V.size.y; j++) { |
| 195 | if (this.board[i][j] == V.EMPTY) emptySquares.push([i, j]); |
| 196 | else if ( |
| 197 | this.getColor(i, j) == color && |
| 198 | this.getPiece(i, j) == V.KNIGHT |
| 199 | ) { |
| 200 | knightCounter++; |
| 201 | } |
| 202 | } |
| 203 | } |
| 204 | if (knightCounter <= 1) finalPieces = [V.KNIGHT]; |
| 205 | else { |
| 206 | // Generate all possible landings |
| 207 | emptySquares.forEach(sq => { |
| 208 | if (sq[0] != lastRank) |
| 209 | moves.push(this.getBasicMove([x1, y1], [sq[0], sq[1]])); |
| 210 | }); |
| 211 | return; |
| 212 | } |
| 213 | } |
| 214 | let tr = null; |
| 215 | for (let piece of finalPieces) { |
| 216 | tr = (piece != V.PAWN ? { c: color, p: piece } : null); |
| 217 | moves.push(this.getBasicMove([x1, y1], [x2, y2], tr)); |
| 218 | } |
| 219 | } |
| 220 | |
| 221 | filterValid(moves) { |
| 222 | // No checks: |
| 223 | return moves; |
| 224 | } |
| 225 | |
| 226 | atLeastOneMove(color) { |
| 227 | const curTurn = this.turn; |
| 228 | this.turn = color; |
| 229 | const res = super.atLeastOneMove(); |
| 230 | this.turn = curTurn; |
| 231 | return res; |
| 232 | } |
| 233 | |
| 234 | // White and black (partial) moves were played: merge |
| 235 | resolveSynchroneMove(move) { |
| 236 | let m = [this.whiteMove, move]; |
| 237 | for (let i of [0, 1]) { |
| 238 | if (!!m[i].illegal) { |
| 239 | // Either an anticipated capture of something which didn't move |
| 240 | // (or not to the right square), or a push through blocus. |
| 241 | if ( |
| 242 | ( |
| 243 | // Push attempt |
| 244 | m[i].start.y == m[i].end.y && |
| 245 | (m[1-i].start.x != m[i].end.x || m[1-i].start.y != m[i].end.y) |
| 246 | ) |
| 247 | || |
| 248 | ( |
| 249 | // Capture attempt |
| 250 | Math.abs(m[i].start.y - m[i].end.y) == 1 && |
| 251 | (m[1-i].end.x != m[i].end.x || m[1-i].end.y != m[i].end.y) |
| 252 | ) |
| 253 | ) { |
| 254 | // Just discard the move, and add a penalty point |
| 255 | this.penaltyFlags[m[i].vanish[0].c]++; |
| 256 | m[i] = null; |
| 257 | } |
| 258 | } |
| 259 | } |
| 260 | |
| 261 | // For PlayOnBoard (no need for start / end, irrelevant) |
| 262 | let smove = { |
| 263 | appear: [], |
| 264 | vanish: [] |
| 265 | }; |
| 266 | const m1 = m[0], |
| 267 | m2 = m[1]; |
| 268 | // If one move is illegal, just execute the other |
| 269 | if (!m1 && !!m2) return m2; |
| 270 | if (!m2 && !!m1) return m1; |
| 271 | if (!m1 && !m2) return smove; |
| 272 | // Both move are now legal: |
| 273 | smove.vanish.push(m1.vanish[0]); |
| 274 | smove.vanish.push(m2.vanish[0]); |
| 275 | if ((m1.end.x != m2.end.x) || (m1.end.y != m2.end.y)) { |
| 276 | // Easy case: two independant moves |
| 277 | smove.appear.push(m1.appear[0]); |
| 278 | smove.appear.push(m2.appear[0]); |
| 279 | // "Captured" pieces may have moved: |
| 280 | if ( |
| 281 | m1.vanish.length == 2 && |
| 282 | ( |
| 283 | m1.vanish[1].x != m2.start.x || |
| 284 | m1.vanish[1].y != m2.start.y |
| 285 | ) |
| 286 | ) { |
| 287 | smove.vanish.push(m1.vanish[1]); |
| 288 | } |
| 289 | if ( |
| 290 | m2.vanish.length == 2 && |
| 291 | ( |
| 292 | m2.vanish[1].x != m1.start.x || |
| 293 | m2.vanish[1].y != m1.start.y |
| 294 | ) |
| 295 | ) { |
| 296 | smove.vanish.push(m2.vanish[1]); |
| 297 | } |
| 298 | } else { |
| 299 | // Collision: both disappear except if different kinds (knight remains) |
| 300 | const p1 = m1.vanish[0].p; |
| 301 | const p2 = m2.vanish[0].p; |
| 302 | if ([p1, p2].includes(V.KNIGHT) && [p1, p2].includes(V.PAWN)) { |
| 303 | smove.appear.push({ |
| 304 | x: m1.end.x, |
| 305 | y: m1.end.y, |
| 306 | p: V.KNIGHT, |
| 307 | c: (p1 == V.KNIGHT ? 'w' : 'b') |
| 308 | }); |
| 309 | } |
| 310 | } |
| 311 | return smove; |
| 312 | } |
| 313 | |
| 314 | play(move) { |
| 315 | // Do not play on board (would reveal the move...) |
| 316 | move.flags = JSON.stringify(this.aggregateFlags()); |
| 317 | this.turn = V.GetOppCol(this.turn); |
| 318 | this.movesCount++; |
| 319 | this.postPlay(move); |
| 320 | } |
| 321 | |
| 322 | postPlay(move) { |
| 323 | if (this.turn == 'b') { |
| 324 | // NOTE: whiteMove is used read-only, so no need to copy |
| 325 | this.whiteMove = move; |
| 326 | return; |
| 327 | } |
| 328 | |
| 329 | // A full turn just ended: |
| 330 | const smove = this.resolveSynchroneMove(move); |
| 331 | V.PlayOnBoard(this.board, smove); |
| 332 | move.whiteMove = this.whiteMove; //for undo |
| 333 | this.whiteMove = null; |
| 334 | move.smove = smove; |
| 335 | } |
| 336 | |
| 337 | undo(move) { |
| 338 | this.disaggregateFlags(JSON.parse(move.flags)); |
| 339 | if (this.turn == 'w') |
| 340 | // Back to the middle of the move |
| 341 | V.UndoOnBoard(this.board, move.smove); |
| 342 | this.turn = V.GetOppCol(this.turn); |
| 343 | this.movesCount--; |
| 344 | this.postUndo(move); |
| 345 | } |
| 346 | |
| 347 | postUndo(move) { |
| 348 | if (this.turn == 'w') this.whiteMove = null; |
| 349 | else this.whiteMove = move.whiteMove; |
| 350 | } |
| 351 | |
| 352 | getCheckSquares(color) { |
| 353 | return []; |
| 354 | } |
| 355 | |
| 356 | getCurrentScore() { |
| 357 | if (this.turn == 'b') |
| 358 | // Turn (white + black) not over yet |
| 359 | return "*"; |
| 360 | // Count footmen: if a side has none, it loses |
| 361 | let fmCount = { 'w': 0, 'b': 0 }; |
| 362 | for (let i=0; i<5; i++) { |
| 363 | for (let j=0; j<5; j++) { |
| 364 | if (this.board[i][j] != V.EMPTY && this.getPiece(i, j) == V.PAWN) |
| 365 | fmCount[this.getColor(i, j)]++; |
| 366 | } |
| 367 | } |
| 368 | if (Object.values(fmCount).some(v => v == 0)) { |
| 369 | if (fmCount['w'] == 0 && fmCount['b'] == 0) |
| 370 | // Everyone died |
| 371 | return "1/2"; |
| 372 | if (fmCount['w'] == 0) return "0-1"; |
| 373 | return "1-0"; //fmCount['b'] == 0 |
| 374 | } |
| 375 | // Check penaltyFlags: if a side has 2 or more, it loses |
| 376 | if (this.penaltyFlags.every(f => f == 2)) return "1/2"; |
| 377 | if (this.penaltyFlags[0] == 2) return "0-1"; |
| 378 | if (this.penaltyFlags[1] == 2) return "1-0"; |
| 379 | if (!this.atLeastOneMove('w') || !this.atLeastOneMove('b')) |
| 380 | // Stalemate (should be very rare) |
| 381 | return "1/2"; |
| 382 | return "*"; |
| 383 | } |
| 384 | |
| 385 | getComputerMove() { |
| 386 | const maxeval = V.INFINITY; |
| 387 | const color = this.turn; |
| 388 | let moves = this.getAllValidMoves(); |
| 389 | if (moves.length == 0) |
| 390 | // TODO: this situation should not happen |
| 391 | return null; |
| 392 | |
| 393 | if (Math.random() < 0.5) |
| 394 | // Return a random move |
| 395 | return moves[randInt(moves.length)]; |
| 396 | |
| 397 | // Rank moves at depth 1: |
| 398 | // try to capture something (not re-capturing) |
| 399 | moves.forEach(m => { |
| 400 | V.PlayOnBoard(this.board, m); |
| 401 | m.eval = this.evalPosition(); |
| 402 | V.UndoOnBoard(this.board, m); |
| 403 | }); |
| 404 | moves.sort((a, b) => { |
| 405 | return (color == "w" ? 1 : -1) * (b.eval - a.eval); |
| 406 | }); |
| 407 | let candidates = [0]; |
| 408 | for (let i = 1; i < moves.length && moves[i].eval == moves[0].eval; i++) |
| 409 | candidates.push(i); |
| 410 | return moves[candidates[randInt(candidates.length)]]; |
| 411 | } |
| 412 | |
| 413 | getNotation(move) { |
| 414 | // Basic system: piece + init + dest square |
| 415 | return ( |
| 416 | move.vanish[0].p.toUpperCase() + |
| 417 | V.CoordsToSquare(move.start) + |
| 418 | V.CoordsToSquare(move.end) |
| 419 | ); |
| 420 | } |
| 421 | }; |