| 1 | import { ChessRules } from "@/base_rules"; |
| 2 | import { randInt } from "@/utils/alea"; |
| 3 | |
| 4 | export class MonsterRules extends ChessRules { |
| 5 | static IsGoodFlags(flags) { |
| 6 | // Only black can castle |
| 7 | return !!flags.match(/^[a-z]{2,2}$/); |
| 8 | } |
| 9 | |
| 10 | static GenRandInitFen(randomness) { |
| 11 | if (randomness == 2) randomness--; |
| 12 | const fen = ChessRules.GenRandInitFen(randomness); |
| 13 | return ( |
| 14 | // 26 first chars are 6 rows + 6 slashes |
| 15 | fen.substr(0, 26) |
| 16 | // En passant available, and "half-castle" |
| 17 | .concat("1PPPPPP1/4K3 w 0 ") |
| 18 | .concat(fen.substr(-6, 2)) |
| 19 | .concat(" -") |
| 20 | ); |
| 21 | } |
| 22 | |
| 23 | getFlagsFen() { |
| 24 | return this.castleFlags['b'].map(V.CoordToColumn).join(""); |
| 25 | } |
| 26 | |
| 27 | setFlags(fenflags) { |
| 28 | this.castleFlags = { 'b': [-1, -1] }; |
| 29 | for (let i = 0; i < 2; i++) |
| 30 | this.castleFlags['b'][i] = V.ColumnToCoord(fenflags.charAt(i)); |
| 31 | } |
| 32 | |
| 33 | setOtherVariables(fen) { |
| 34 | super.setOtherVariables(fen); |
| 35 | this.subTurn = 1; |
| 36 | } |
| 37 | |
| 38 | getPotentialKingMoves([x, y]) { |
| 39 | if (this.getColor(x, y) == 'b') return super.getPotentialKingMoves([x, y]); |
| 40 | // White doesn't castle: |
| 41 | return this.getSlideNJumpMoves( |
| 42 | [x, y], |
| 43 | V.steps[V.ROOK].concat(V.steps[V.BISHOP]), |
| 44 | "oneStep" |
| 45 | ); |
| 46 | } |
| 47 | |
| 48 | isAttacked() { |
| 49 | // Goal is king capture => no checks |
| 50 | return false; |
| 51 | } |
| 52 | |
| 53 | filterValid(moves) { |
| 54 | return moves; |
| 55 | } |
| 56 | |
| 57 | getCheckSquares() { |
| 58 | return []; |
| 59 | } |
| 60 | |
| 61 | getCurrentScore() { |
| 62 | const color = this.turn; |
| 63 | if (this.kingPos[color][0] < 0) return (color == 'w' ? "0-1" : "1-0"); |
| 64 | return "*"; |
| 65 | } |
| 66 | |
| 67 | play(move) { |
| 68 | move.flags = JSON.stringify(this.aggregateFlags()); |
| 69 | if (this.turn == 'b' || this.subTurn == 2) |
| 70 | this.epSquares.push(this.getEpSquare(move)); |
| 71 | else this.epSquares.push(null); |
| 72 | V.PlayOnBoard(this.board, move); |
| 73 | if (this.turn == 'w') { |
| 74 | if (this.subTurn == 1) this.movesCount++; |
| 75 | if ( |
| 76 | this.subTurn == 2 || |
| 77 | // King captured |
| 78 | (move.vanish.length == 2 && move.vanish[1].p == V.KING) |
| 79 | ) { |
| 80 | this.turn = 'b'; |
| 81 | this.subTurn = 1; |
| 82 | } |
| 83 | else this.subTurn = 2; |
| 84 | } |
| 85 | else { |
| 86 | this.turn = 'w'; |
| 87 | this.movesCount++; |
| 88 | } |
| 89 | this.postPlay(move); |
| 90 | } |
| 91 | |
| 92 | updateCastleFlags(move, piece) { |
| 93 | // Only black can castle: |
| 94 | const firstRank = 0; |
| 95 | if (piece == V.KING && move.appear[0].c == 'b') |
| 96 | this.castleFlags['b'] = [8, 8]; |
| 97 | else if ( |
| 98 | move.start.x == firstRank && |
| 99 | this.castleFlags['b'].includes(move.start.y) |
| 100 | ) { |
| 101 | const flagIdx = (move.start.y == this.castleFlags['b'][0] ? 0 : 1); |
| 102 | this.castleFlags['b'][flagIdx] = 8; |
| 103 | } |
| 104 | else if ( |
| 105 | move.end.x == firstRank && |
| 106 | this.castleFlags['b'].includes(move.end.y) |
| 107 | ) { |
| 108 | const flagIdx = (move.end.y == this.castleFlags['b'][0] ? 0 : 1); |
| 109 | this.castleFlags['b'][flagIdx] = 8; |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | postPlay(move) { |
| 114 | // Definition of 'c' in base class doesn't work: |
| 115 | const c = move.vanish[0].c; |
| 116 | const piece = move.vanish[0].p; |
| 117 | if (piece == V.KING) |
| 118 | this.kingPos[c] = [move.appear[0].x, move.appear[0].y]; |
| 119 | if (move.vanish.length == 2 && move.vanish[1].p == V.KING) { |
| 120 | // Opponent's king is captured, game over |
| 121 | this.kingPos[move.vanish[1].c] = [-1, -1]; |
| 122 | move.captureKing = true; //for undo |
| 123 | } |
| 124 | this.updateCastleFlags(move, piece); |
| 125 | } |
| 126 | |
| 127 | undo(move) { |
| 128 | this.epSquares.pop(); |
| 129 | this.disaggregateFlags(JSON.parse(move.flags)); |
| 130 | V.UndoOnBoard(this.board, move); |
| 131 | if (this.turn == 'w') { |
| 132 | if (this.subTurn == 2) this.subTurn = 1; |
| 133 | else this.turn = 'b'; |
| 134 | this.movesCount--; |
| 135 | } |
| 136 | else { |
| 137 | this.turn = 'w'; |
| 138 | this.subTurn = (!move.captureKing ? 2 : 1); |
| 139 | } |
| 140 | this.postUndo(move); |
| 141 | } |
| 142 | |
| 143 | postUndo(move) { |
| 144 | if (move.vanish.length == 2 && move.vanish[1].p == V.KING) |
| 145 | // Opponent's king was captured |
| 146 | this.kingPos[move.vanish[1].c] = [move.vanish[1].x, move.vanish[1].y]; |
| 147 | super.postUndo(move); |
| 148 | } |
| 149 | |
| 150 | // Custom search at depth 1(+1) |
| 151 | getComputerMove() { |
| 152 | const getBestWhiteMove = (terminal) => { |
| 153 | // Generate all sequences of 2-moves |
| 154 | let moves1 = this.getAllValidMoves(); |
| 155 | moves1.forEach(m1 => { |
| 156 | m1.eval = -V.INFINITY; |
| 157 | m1.move2 = null; |
| 158 | this.play(m1); |
| 159 | if (!!terminal) m1.eval = this.evalPosition(); |
| 160 | else { |
| 161 | const moves2 = this.getAllValidMoves(); |
| 162 | moves2.forEach(m2 => { |
| 163 | this.play(m2); |
| 164 | const eval2 = this.evalPosition() + 0.05 - Math.random() / 10; |
| 165 | this.undo(m2); |
| 166 | if (eval2 > m1.eval) { |
| 167 | m1.eval = eval2; |
| 168 | m1.move2 = m2; |
| 169 | } |
| 170 | }); |
| 171 | } |
| 172 | this.undo(m1); |
| 173 | }); |
| 174 | moves1.sort((a, b) => b.eval - a.eval); |
| 175 | if (!!terminal) |
| 176 | // The move itself doesn't matter, only its eval: |
| 177 | return moves1[0]; |
| 178 | let candidates = [0]; |
| 179 | for ( |
| 180 | let i = 1; |
| 181 | i < moves1.length && moves1[i].eval == moves1[0].eval; |
| 182 | i++ |
| 183 | ) { |
| 184 | candidates.push(i); |
| 185 | } |
| 186 | const idx = candidates[randInt(candidates.length)]; |
| 187 | const move2 = moves1[idx].move2; |
| 188 | delete moves1[idx]["move2"]; |
| 189 | return [moves1[idx], move2]; |
| 190 | }; |
| 191 | |
| 192 | const getBestBlackMove = () => { |
| 193 | let moves = this.getAllValidMoves(); |
| 194 | moves.forEach(m => { |
| 195 | m.eval = V.INFINITY; |
| 196 | this.play(m); |
| 197 | const evalM = getBestWhiteMove("terminal").eval |
| 198 | this.undo(m); |
| 199 | if (evalM < m.eval) m.eval = evalM; |
| 200 | }); |
| 201 | moves.sort((a, b) => a.eval - b.eval); |
| 202 | let candidates = [0]; |
| 203 | for ( |
| 204 | let i = 1; |
| 205 | i < moves.length && moves[i].eval == moves[0].eval; |
| 206 | i++ |
| 207 | ) { |
| 208 | candidates.push(i); |
| 209 | } |
| 210 | const idx = candidates[randInt(candidates.length)]; |
| 211 | return moves[idx]; |
| 212 | }; |
| 213 | |
| 214 | const color = this.turn; |
| 215 | return (color == 'w' ? getBestWhiteMove() : getBestBlackMove()); |
| 216 | } |
| 217 | }; |