| 1 | import { ChessRules, Move, PiPo } from "@/base_rules"; |
| 2 | import { randInt } from "@/utils/alea"; |
| 3 | |
| 4 | export class FanoronaRules extends ChessRules { |
| 5 | |
| 6 | static get HasFlags() { |
| 7 | return false; |
| 8 | } |
| 9 | |
| 10 | static get HasEnpassant() { |
| 11 | return false; |
| 12 | } |
| 13 | |
| 14 | static get Monochrome() { |
| 15 | return true; |
| 16 | } |
| 17 | |
| 18 | static get Lines() { |
| 19 | let lines = []; |
| 20 | // Draw all inter-squares lines, shifted: |
| 21 | for (let i = 0; i < V.size.x; i++) |
| 22 | lines.push([[i+0.5, 0.5], [i+0.5, V.size.y-0.5]]); |
| 23 | for (let j = 0; j < V.size.y; j++) |
| 24 | lines.push([[0.5, j+0.5], [V.size.x-0.5, j+0.5]]); |
| 25 | const columnDiags = [ |
| 26 | [[0.5, 0.5], [2.5, 2.5]], |
| 27 | [[0.5, 2.5], [2.5, 0.5]], |
| 28 | [[2.5, 0.5], [4.5, 2.5]], |
| 29 | [[4.5, 0.5], [2.5, 2.5]] |
| 30 | ]; |
| 31 | for (let j of [0, 2, 4, 6]) { |
| 32 | lines = lines.concat( |
| 33 | columnDiags.map(L => [[L[0][0], L[0][1] + j], [L[1][0], L[1][1] + j]]) |
| 34 | ); |
| 35 | } |
| 36 | return lines; |
| 37 | } |
| 38 | |
| 39 | static get Notoodark() { |
| 40 | return true; |
| 41 | } |
| 42 | |
| 43 | static GenRandInitFen() { |
| 44 | return "ppppppppp/ppppppppp/pPpP1pPpP/PPPPPPPPP/PPPPPPPPP w 0"; |
| 45 | } |
| 46 | |
| 47 | setOtherVariables(fen) { |
| 48 | // Local stack of captures during a turn (squares + directions) |
| 49 | this.captures = [ [] ]; |
| 50 | } |
| 51 | |
| 52 | static get size() { |
| 53 | return { x: 5, y: 9 }; |
| 54 | } |
| 55 | |
| 56 | getPiece() { |
| 57 | return V.PAWN; |
| 58 | } |
| 59 | |
| 60 | static IsGoodPosition(position) { |
| 61 | if (position.length == 0) return false; |
| 62 | const rows = position.split("/"); |
| 63 | if (rows.length != V.size.x) return false; |
| 64 | for (let row of rows) { |
| 65 | let sumElts = 0; |
| 66 | for (let i = 0; i < row.length; i++) { |
| 67 | if (row[i].toLowerCase() == V.PAWN) sumElts++; |
| 68 | else { |
| 69 | const num = parseInt(row[i], 10); |
| 70 | if (isNaN(num) || num <= 0) return false; |
| 71 | sumElts += num; |
| 72 | } |
| 73 | } |
| 74 | if (sumElts != V.size.y) return false; |
| 75 | } |
| 76 | return true; |
| 77 | } |
| 78 | |
| 79 | getPpath(b) { |
| 80 | return "Fanorona/" + b; |
| 81 | } |
| 82 | |
| 83 | getPPpath(m) { |
| 84 | // m.vanish.length >= 2, first capture gives direction |
| 85 | const ref = (Math.abs(m.vanish[1].x - m.start.x) == 1 ? m.start : m.end); |
| 86 | const step = [m.vanish[1].x - ref.x, m.vanish[1].y - ref.y]; |
| 87 | const normalizedStep = [ |
| 88 | step[0] / Math.abs(step[0]), |
| 89 | step[1] / Math.abs(step[1]) |
| 90 | ]; |
| 91 | return ( |
| 92 | "Fanorona/arrow_" + |
| 93 | (normalizedStep[0] || 0) + "_" + (normalizedStep[1] || 0) |
| 94 | ); |
| 95 | } |
| 96 | |
| 97 | // After moving, add stones captured in "step" direction from new location |
| 98 | // [x, y] to mv.vanish (if any captured stone!) |
| 99 | addCapture([x, y], step, move) { |
| 100 | let [i, j] = [x + step[0], y + step[1]]; |
| 101 | const oppCol = V.GetOppCol(move.vanish[0].c); |
| 102 | while ( |
| 103 | V.OnBoard(i, j) && |
| 104 | this.board[i][j] != V.EMPTY && |
| 105 | this.getColor(i, j) == oppCol |
| 106 | ) { |
| 107 | move.vanish.push(new PiPo({ x: i, y: j, c: oppCol, p: V.PAWN })); |
| 108 | i += step[0]; |
| 109 | j += step[1]; |
| 110 | } |
| 111 | return (move.vanish.length >= 2); |
| 112 | } |
| 113 | |
| 114 | getPotentialMovesFrom([x, y]) { |
| 115 | const L0 = this.captures.length; |
| 116 | const captures = this.captures[L0 - 1]; |
| 117 | const L = captures.length; |
| 118 | if (L > 0) { |
| 119 | var c = captures[L-1]; |
| 120 | if (x != c.square.x + c.step[0] || y != c.square.y + c.step[1]) |
| 121 | return []; |
| 122 | } |
| 123 | const oppCol = V.GetOppCol(this.turn); |
| 124 | let steps = V.steps[V.ROOK]; |
| 125 | if ((x + y) % 2 == 0) steps = steps.concat(V.steps[V.BISHOP]); |
| 126 | let moves = []; |
| 127 | for (let s of steps) { |
| 128 | if (L > 0 && c.step[0] == s[0] && c.step[1] == s[1]) { |
| 129 | // Add a move to say "I'm done capturing" |
| 130 | moves.push( |
| 131 | new Move({ |
| 132 | appear: [], |
| 133 | vanish: [], |
| 134 | start: { x: x, y: y }, |
| 135 | end: { x: x - s[0], y: y - s[1] } |
| 136 | }) |
| 137 | ); |
| 138 | continue; |
| 139 | } |
| 140 | let [i, j] = [x + s[0], y + s[1]]; |
| 141 | if (captures.some(c => c.square.x == i && c.square.y == j)) continue; |
| 142 | if (V.OnBoard(i, j) && this.board[i][j] == V.EMPTY) { |
| 143 | // The move is potentially allowed. Might lead to 2 different captures |
| 144 | let mv = super.getBasicMove([x, y], [i, j]); |
| 145 | const capt = this.addCapture([i, j], s, mv); |
| 146 | if (capt) { |
| 147 | moves.push(mv); |
| 148 | mv = super.getBasicMove([x, y], [i, j]); |
| 149 | } |
| 150 | const capt_bw = this.addCapture([x, y], [-s[0], -s[1]], mv); |
| 151 | if (capt_bw) moves.push(mv); |
| 152 | // Captures take priority (if available) |
| 153 | if (!capt && !capt_bw && L == 0) moves.push(mv); |
| 154 | } |
| 155 | } |
| 156 | return moves; |
| 157 | } |
| 158 | |
| 159 | atLeastOneCapture() { |
| 160 | const color = this.turn; |
| 161 | const oppCol = V.GetOppCol(color); |
| 162 | const L0 = this.captures.length; |
| 163 | const captures = this.captures[L0 - 1]; |
| 164 | const L = captures.length; |
| 165 | if (L > 0) { |
| 166 | // If some adjacent enemy stone, with free space to capture it, |
| 167 | // toward a square not already visited, through a different step |
| 168 | // from last one: then yes. |
| 169 | const c = captures[L-1]; |
| 170 | const [x, y] = [c.square.x + c.step[0], c.square.y + c.step[1]]; |
| 171 | let steps = V.steps[V.ROOK]; |
| 172 | if ((x + y) % 2 == 0) steps = steps.concat(V.steps[V.BISHOP]); |
| 173 | // TODO: half of the steps explored are redundant |
| 174 | for (let s of steps) { |
| 175 | if (s[0] == c.step[0] && s[1] == c.step[1]) continue; |
| 176 | const [i, j] = [x + s[0], y + s[1]]; |
| 177 | if ( |
| 178 | !V.OnBoard(i, j) || |
| 179 | this.board[i][j] != V.EMPTY || |
| 180 | captures.some(c => c.square.x == i && c.square.y == j) |
| 181 | ) { |
| 182 | continue; |
| 183 | } |
| 184 | if ( |
| 185 | V.OnBoard(i + s[0], j + s[1]) && |
| 186 | this.board[i + s[0]][j + s[1]] != V.EMPTY && |
| 187 | this.getColor(i + s[0], j + s[1]) == oppCol |
| 188 | ) { |
| 189 | return true; |
| 190 | } |
| 191 | if ( |
| 192 | V.OnBoard(x - s[0], y - s[1]) && |
| 193 | this.board[x - s[0]][y - s[1]] != V.EMPTY && |
| 194 | this.getColor(x - s[0], y - s[1]) == oppCol |
| 195 | ) { |
| 196 | return true; |
| 197 | } |
| 198 | } |
| 199 | return false; |
| 200 | } |
| 201 | for (let i = 0; i < V.size.x; i++) { |
| 202 | for (let j = 0; j < V.size.y; j++) { |
| 203 | if ( |
| 204 | this.board[i][j] != V.EMPTY && |
| 205 | this.getColor(i, j) == color && |
| 206 | // TODO: this could be more efficient |
| 207 | this.getPotentialMovesFrom([i, j]).some(m => m.vanish.length >= 2) |
| 208 | ) { |
| 209 | return true; |
| 210 | } |
| 211 | } |
| 212 | } |
| 213 | return false; |
| 214 | } |
| 215 | |
| 216 | static KeepCaptures(moves) { |
| 217 | return moves.filter(m => m.vanish.length >= 2); |
| 218 | } |
| 219 | |
| 220 | getPossibleMovesFrom(sq) { |
| 221 | let moves = this.getPotentialMovesFrom(sq); |
| 222 | const L0 = this.captures.length; |
| 223 | const captures = this.captures[L0 - 1]; |
| 224 | if (captures.length > 0) return this.getPotentialMovesFrom(sq); |
| 225 | const captureMoves = V.KeepCaptures(moves); |
| 226 | if (captureMoves.length > 0) return captureMoves; |
| 227 | if (this.atLeastOneCapture()) return []; |
| 228 | return moves; |
| 229 | } |
| 230 | |
| 231 | getAllValidMoves() { |
| 232 | const moves = super.getAllValidMoves(); |
| 233 | if (moves.some(m => m.vanish.length >= 2)) return V.KeepCaptures(moves); |
| 234 | return moves; |
| 235 | } |
| 236 | |
| 237 | filterValid(moves) { |
| 238 | return moves; |
| 239 | } |
| 240 | |
| 241 | getCheckSquares() { |
| 242 | return []; |
| 243 | } |
| 244 | |
| 245 | play(move) { |
| 246 | const color = this.turn; |
| 247 | move.turn = color; //for undo |
| 248 | V.PlayOnBoard(this.board, move); |
| 249 | const L0 = this.captures.length; |
| 250 | let captures = this.captures[L0 - 1]; |
| 251 | if (move.vanish.length >= 2) { |
| 252 | captures.push({ |
| 253 | square: move.start, |
| 254 | step: [move.end.x - move.start.x, move.end.y - move.start.y] |
| 255 | }); |
| 256 | if (this.atLeastOneCapture()) |
| 257 | // There could be other captures (optional) |
| 258 | // This field is mostly useful for computer play. |
| 259 | move.notTheEnd = true; |
| 260 | else captures.pop(); //useless now |
| 261 | } |
| 262 | if (!move.notTheEnd) { |
| 263 | this.turn = V.GetOppCol(color); |
| 264 | this.movesCount++; |
| 265 | this.captures.push([]); |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | undo(move) { |
| 270 | V.UndoOnBoard(this.board, move); |
| 271 | if (move.turn != this.turn) { |
| 272 | this.turn = move.turn; |
| 273 | this.movesCount--; |
| 274 | this.captures.pop(); |
| 275 | } |
| 276 | else { |
| 277 | const L0 = this.captures.length; |
| 278 | let captures = this.captures[L0 - 1]; |
| 279 | captures.pop(); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | getCurrentScore() { |
| 284 | const color = this.turn; |
| 285 | // If no stones on board, I lose |
| 286 | if ( |
| 287 | this.board.every(b => { |
| 288 | return b.every(cell => { |
| 289 | return (cell == "" || cell[0] != color); |
| 290 | }); |
| 291 | }) |
| 292 | ) { |
| 293 | return (color == 'w' ? "0-1" : "1-0"); |
| 294 | } |
| 295 | return "*"; |
| 296 | } |
| 297 | |
| 298 | getComputerMove() { |
| 299 | const moves = this.getAllValidMoves(); |
| 300 | if (moves.length == 0) return null; |
| 301 | const color = this.turn; |
| 302 | // Capture available? If yes, play it |
| 303 | let captures = moves.filter(m => m.vanish.length >= 2); |
| 304 | let mvArray = []; |
| 305 | while (captures.length >= 1) { |
| 306 | // Then just pick random captures (trying to maximize) |
| 307 | let candidates = captures.filter(c => !!c.notTheEnd); |
| 308 | let mv = null; |
| 309 | if (candidates.length >= 1) mv = candidates[randInt(candidates.length)]; |
| 310 | else mv = captures[randInt(captures.length)]; |
| 311 | this.play(mv); |
| 312 | mvArray.push(mv); |
| 313 | captures = (this.turn == color ? this.getAllValidMoves() : []); |
| 314 | } |
| 315 | if (mvArray.length >= 1) { |
| 316 | for (let i = mvArray.length - 1; i >= 0; i--) this.undo(mvArray[i]); |
| 317 | return mvArray; |
| 318 | } |
| 319 | // Just play a random move, which if possible does not let a capture |
| 320 | let candidates = []; |
| 321 | for (let m of moves) { |
| 322 | this.play(m); |
| 323 | if (!this.atLeastOneCapture()) candidates.push(m); |
| 324 | this.undo(m); |
| 325 | } |
| 326 | if (candidates.length >= 1) return candidates[randInt(candidates.length)]; |
| 327 | return moves[randInt(moves.length)]; |
| 328 | } |
| 329 | |
| 330 | getNotation(move) { |
| 331 | if (move.appear.length == 0) return "stop"; |
| 332 | return ( |
| 333 | V.CoordsToSquare(move.start) + |
| 334 | V.CoordsToSquare(move.end) + |
| 335 | (move.vanish.length >= 2 ? "X" : "") |
| 336 | ); |
| 337 | } |
| 338 | |
| 339 | }; |