| 1 | import { ChessRules, Move, PiPo } from "@/base_rules"; |
| 2 | import { ArrayFun } from "@/utils/array"; |
| 3 | import { randInt, sample } from "@/utils/alea"; |
| 4 | |
| 5 | export class ShakoRules extends ChessRules { |
| 6 | static get PawnSpecs() { |
| 7 | return Object.assign( |
| 8 | {}, |
| 9 | ChessRules.PawnSpecs, |
| 10 | { |
| 11 | initShift: { w: 2, b: 2 }, |
| 12 | promotions: |
| 13 | ChessRules.PawnSpecs.promotions.concat([V.ELEPHANT, V.CANNON]) |
| 14 | } |
| 15 | ); |
| 16 | } |
| 17 | |
| 18 | static get ELEPHANT() { |
| 19 | return "e"; |
| 20 | } |
| 21 | |
| 22 | static get CANNON() { |
| 23 | return "c"; |
| 24 | } |
| 25 | |
| 26 | static get PIECES() { |
| 27 | return ChessRules.PIECES.concat([V.ELEPHANT, V.CANNON]); |
| 28 | } |
| 29 | |
| 30 | getPpath(b) { |
| 31 | const prefix = [V.ELEPHANT, V.CANNON].includes(b[1]) ? "Shako/" : ""; |
| 32 | return prefix + b; |
| 33 | } |
| 34 | |
| 35 | static get steps() { |
| 36 | return Object.assign( |
| 37 | {}, |
| 38 | ChessRules.steps, |
| 39 | { |
| 40 | e: [ |
| 41 | [-1, -1], |
| 42 | [-1, 1], |
| 43 | [1, -1], |
| 44 | [1, 1], |
| 45 | [-2, -2], |
| 46 | [-2, 2], |
| 47 | [2, -2], |
| 48 | [2, 2] |
| 49 | ] |
| 50 | } |
| 51 | ); |
| 52 | } |
| 53 | |
| 54 | static get size() { |
| 55 | return { x: 10, y: 10}; |
| 56 | } |
| 57 | |
| 58 | getPotentialMovesFrom([x, y]) { |
| 59 | switch (this.getPiece(x, y)) { |
| 60 | case V.ELEPHANT: |
| 61 | return this.getPotentialElephantMoves([x, y]); |
| 62 | case V.CANNON: |
| 63 | return this.getPotentialCannonMoves([x, y]); |
| 64 | default: |
| 65 | return super.getPotentialMovesFrom([x, y]); |
| 66 | } |
| 67 | } |
| 68 | |
| 69 | getPotentialElephantMoves([x, y]) { |
| 70 | return this.getSlideNJumpMoves([x, y], V.steps[V.ELEPHANT], "oneStep"); |
| 71 | } |
| 72 | |
| 73 | getPotentialCannonMoves([x, y]) { |
| 74 | const oppCol = V.GetOppCol(this.turn); |
| 75 | let moves = []; |
| 76 | // Look in every direction until an obstacle (to jump) is met |
| 77 | for (const step of V.steps[V.ROOK]) { |
| 78 | let i = x + step[0]; |
| 79 | let j = y + step[1]; |
| 80 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
| 81 | moves.push(this.getBasicMove([x, y], [i, j])); |
| 82 | i += step[0]; |
| 83 | j += step[1]; |
| 84 | } |
| 85 | // Then, search for an enemy |
| 86 | i += step[0]; |
| 87 | j += step[1]; |
| 88 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
| 89 | i += step[0]; |
| 90 | j += step[1]; |
| 91 | } |
| 92 | if (V.OnBoard(i, j) && this.getColor(i, j) == oppCol) |
| 93 | moves.push(this.getBasicMove([x, y], [i, j])); |
| 94 | } |
| 95 | return moves; |
| 96 | } |
| 97 | |
| 98 | getCastleMoves([x, y]) { |
| 99 | const c = this.getColor(x, y); |
| 100 | if (x != (c == "w" ? V.size.x - 2 : 1) || y != this.INIT_COL_KING[c]) |
| 101 | return []; //x isn't second rank, or king has moved (shortcut) |
| 102 | |
| 103 | // Castling ? |
| 104 | const oppCol = V.GetOppCol(c); |
| 105 | let moves = []; |
| 106 | let i = 0; |
| 107 | // King, then rook: |
| 108 | const finalSquares = [ |
| 109 | [3, 4], |
| 110 | [7, 6] |
| 111 | ]; |
| 112 | castlingCheck: for ( |
| 113 | let castleSide = 0; |
| 114 | castleSide < 2; |
| 115 | castleSide++ //large, then small |
| 116 | ) { |
| 117 | if (this.castleFlags[c][castleSide] >= V.size.y) continue; |
| 118 | // If this code is reached, rook and king are on initial position |
| 119 | |
| 120 | const rookPos = this.castleFlags[c][castleSide]; |
| 121 | |
| 122 | // Nothing on the path of the king ? (and no checks) |
| 123 | const castlingPiece = this.getPiece(x, rookPos); |
| 124 | const finDist = finalSquares[castleSide][0] - y; |
| 125 | let step = finDist / Math.max(1, Math.abs(finDist)); |
| 126 | i = y; |
| 127 | do { |
| 128 | if ( |
| 129 | this.isAttacked([x, i], oppCol) || |
| 130 | (this.board[x][i] != V.EMPTY && |
| 131 | // NOTE: next check is enough, because of chessboard constraints |
| 132 | (this.getColor(x, i) != c || |
| 133 | ![V.KING, castlingPiece].includes(this.getPiece(x, i)))) |
| 134 | ) { |
| 135 | continue castlingCheck; |
| 136 | } |
| 137 | i += step; |
| 138 | } while (i != finalSquares[castleSide][0]); |
| 139 | |
| 140 | // Nothing on the path to the rook? |
| 141 | step = castleSide == 0 ? -1 : 1; |
| 142 | for (i = y + step; i != rookPos; i += step) { |
| 143 | if (this.board[x][i] != V.EMPTY) continue castlingCheck; |
| 144 | } |
| 145 | |
| 146 | // Nothing on final squares, except maybe king and castling rook? |
| 147 | for (i = 0; i < 2; i++) { |
| 148 | if ( |
| 149 | finalSquares[castleSide][i] != rookPos && |
| 150 | this.board[x][finalSquares[castleSide][i]] != V.EMPTY && |
| 151 | ( |
| 152 | this.getPiece(x, finalSquares[castleSide][i]) != V.KING || |
| 153 | this.getColor(x, finalSquares[castleSide][i]) != c |
| 154 | ) |
| 155 | ) { |
| 156 | continue castlingCheck; |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | // If this code is reached, castle is valid |
| 161 | moves.push( |
| 162 | new Move({ |
| 163 | appear: [ |
| 164 | new PiPo({ |
| 165 | x: x, |
| 166 | y: finalSquares[castleSide][0], |
| 167 | p: V.KING, |
| 168 | c: c |
| 169 | }), |
| 170 | new PiPo({ |
| 171 | x: x, |
| 172 | y: finalSquares[castleSide][1], |
| 173 | p: castlingPiece, |
| 174 | c: c |
| 175 | }) |
| 176 | ], |
| 177 | vanish: [ |
| 178 | new PiPo({ x: x, y: y, p: V.KING, c: c }), |
| 179 | new PiPo({ x: x, y: rookPos, p: castlingPiece, c: c }) |
| 180 | ], |
| 181 | end: |
| 182 | Math.abs(y - rookPos) <= 2 |
| 183 | ? { x: x, y: rookPos } |
| 184 | : { x: x, y: y + 2 * (castleSide == 0 ? -1 : 1) } |
| 185 | }) |
| 186 | ); |
| 187 | } |
| 188 | |
| 189 | return moves; |
| 190 | } |
| 191 | |
| 192 | isAttacked(sq, color) { |
| 193 | return ( |
| 194 | super.isAttacked(sq, color) || |
| 195 | this.isAttackedByElephant(sq, color) || |
| 196 | this.isAttackedByCannon(sq, color) |
| 197 | ); |
| 198 | } |
| 199 | |
| 200 | isAttackedByElephant(sq, color) { |
| 201 | return ( |
| 202 | this.isAttackedBySlideNJump( |
| 203 | sq, color, V.ELEPHANT, V.steps[V.ELEPHANT], "oneStep" |
| 204 | ) |
| 205 | ); |
| 206 | } |
| 207 | |
| 208 | isAttackedByCannon([x, y], color) { |
| 209 | // Reversed process: is there an obstacle in line, |
| 210 | // and a cannon next in the same line? |
| 211 | for (const step of V.steps[V.ROOK]) { |
| 212 | let [i, j] = [x+step[0], y+step[1]]; |
| 213 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
| 214 | i += step[0]; |
| 215 | j += step[1]; |
| 216 | } |
| 217 | if (V.OnBoard(i, j)) { |
| 218 | // Keep looking in this direction |
| 219 | i += step[0]; |
| 220 | j += step[1]; |
| 221 | while (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
| 222 | i += step[0]; |
| 223 | j += step[1]; |
| 224 | } |
| 225 | if ( |
| 226 | V.OnBoard(i, j) && |
| 227 | this.getPiece(i, j) == V.CANNON && |
| 228 | this.getColor(i, j) == color |
| 229 | ) { |
| 230 | return true; |
| 231 | } |
| 232 | } |
| 233 | } |
| 234 | return false; |
| 235 | } |
| 236 | |
| 237 | updateCastleFlags(move, piece) { |
| 238 | const c = V.GetOppCol(this.turn); |
| 239 | const firstRank = (c == "w" ? V.size.x - 2 : 1); |
| 240 | // Update castling flags if rooks are moved |
| 241 | const oppCol = this.turn; |
| 242 | const oppFirstRank = V.size.x - 1 - firstRank; |
| 243 | if (piece == V.KING) |
| 244 | this.castleFlags[c] = [V.size.y, V.size.y]; |
| 245 | else if ( |
| 246 | move.start.x == firstRank && //our rook moves? |
| 247 | this.castleFlags[c].includes(move.start.y) |
| 248 | ) { |
| 249 | const flagIdx = (move.start.y == this.castleFlags[c][0] ? 0 : 1); |
| 250 | this.castleFlags[c][flagIdx] = V.size.y; |
| 251 | } |
| 252 | // NOTE: not "else if" because a rook could take an opposing rook |
| 253 | if ( |
| 254 | move.end.x == oppFirstRank && //we took opponent rook? |
| 255 | this.castleFlags[oppCol].includes(move.end.y) |
| 256 | ) { |
| 257 | const flagIdx = (move.end.y == this.castleFlags[oppCol][0] ? 0 : 1); |
| 258 | this.castleFlags[oppCol][flagIdx] = V.size.y; |
| 259 | } |
| 260 | } |
| 261 | |
| 262 | static get VALUES() { |
| 263 | return Object.assign( |
| 264 | { e: 3, c: 5 }, |
| 265 | ChessRules.VALUES |
| 266 | ); |
| 267 | } |
| 268 | |
| 269 | static get SEARCH_DEPTH() { |
| 270 | return 2; |
| 271 | } |
| 272 | |
| 273 | static GenRandInitFen(randomness) { |
| 274 | if (randomness == 0) { |
| 275 | return ( |
| 276 | "c8c/ernbqkbnre/pppppppppp/91/91/91/91/PPPPPPPPPP/ERNBQKBNRE/C8C " + |
| 277 | "w 0 bibi -" |
| 278 | ); |
| 279 | } |
| 280 | |
| 281 | let pieces = { w: new Array(10), b: new Array(10) }; |
| 282 | let flags = ""; |
| 283 | // Shuffle pieces on second (and before-last rank if randomness == 2) |
| 284 | for (let c of ["w", "b"]) { |
| 285 | if (c == 'b' && randomness == 1) { |
| 286 | pieces['b'] = pieces['w']; |
| 287 | flags += flags; |
| 288 | break; |
| 289 | } |
| 290 | |
| 291 | let positions = ArrayFun.range(10); |
| 292 | |
| 293 | // Get random squares for bishops + elephants |
| 294 | const be1Pos = sample([0, 2, 4, 6, 8], 2); |
| 295 | const be2Pos = sample([1, 3, 5, 7, 9], 2); |
| 296 | const bishop1Pos = be1Pos[0]; |
| 297 | const bishop2Pos = be2Pos[0]; |
| 298 | const elephant1Pos = be1Pos[1]; |
| 299 | const elephant2Pos = be2Pos[1]; |
| 300 | // Remove chosen squares |
| 301 | (be1Pos.concat(be2Pos)).sort((x, y) => y - x).forEach(pos => { |
| 302 | positions.splice(pos, 1); |
| 303 | }); |
| 304 | |
| 305 | let randIndex = randInt(6); |
| 306 | const knight1Pos = positions[randIndex]; |
| 307 | positions.splice(randIndex, 1); |
| 308 | randIndex = randInt(5); |
| 309 | const knight2Pos = positions[randIndex]; |
| 310 | positions.splice(randIndex, 1); |
| 311 | |
| 312 | randIndex = randInt(4); |
| 313 | const queenPos = positions[randIndex]; |
| 314 | positions.splice(randIndex, 1); |
| 315 | |
| 316 | const rook1Pos = positions[0]; |
| 317 | const kingPos = positions[1]; |
| 318 | const rook2Pos = positions[2]; |
| 319 | |
| 320 | pieces[c][elephant1Pos] = "e"; |
| 321 | pieces[c][rook1Pos] = "r"; |
| 322 | pieces[c][knight1Pos] = "n"; |
| 323 | pieces[c][bishop1Pos] = "b"; |
| 324 | pieces[c][queenPos] = "q"; |
| 325 | pieces[c][kingPos] = "k"; |
| 326 | pieces[c][bishop2Pos] = "b"; |
| 327 | pieces[c][knight2Pos] = "n"; |
| 328 | pieces[c][rook2Pos] = "r"; |
| 329 | pieces[c][elephant2Pos] = "e"; |
| 330 | flags += V.CoordToColumn(rook1Pos) + V.CoordToColumn(rook2Pos); |
| 331 | } |
| 332 | // Add turn + flags + enpassant |
| 333 | return ( |
| 334 | "c8c/" + pieces["b"].join("") + |
| 335 | "/pppppppppp/91/91/91/91/PPPPPPPPPP/" + |
| 336 | pieces["w"].join("").toUpperCase() + "/C8C" + |
| 337 | " w 0 " + flags + " -" |
| 338 | ); |
| 339 | } |
| 340 | }; |