| 1 | import { ChessRules } from "@/base_rules"; |
| 2 | |
| 3 | export class RampageRules extends ChessRules { |
| 4 | // Sum white pieces attacking a square, and remove black pieces count. |
| 5 | sumAttacks([x, y]) { |
| 6 | const getSign = (color) => { |
| 7 | return (color == 'w' ? 1 : -1); |
| 8 | }; |
| 9 | let res = 0; |
| 10 | // Knights: |
| 11 | V.steps[V.KNIGHT].forEach(s => { |
| 12 | const [i, j] = [x + s[0], y + s[1]]; |
| 13 | if (V.OnBoard(i, j) && this.getPiece(i, j) == V.KNIGHT) |
| 14 | res += getSign(this.getColor(i, j)); |
| 15 | }); |
| 16 | // Kings: |
| 17 | V.steps[V.ROOK].concat(V.steps[V.BISHOP]).forEach(s => { |
| 18 | const [i, j] = [x + s[0], y + s[1]]; |
| 19 | if (V.OnBoard(i, j) && this.getPiece(i, j) == V.KING) |
| 20 | res += getSign(this.getColor(i, j)); |
| 21 | }); |
| 22 | // Pawns: |
| 23 | for (let c of ['w', 'b']) { |
| 24 | for (let shift of [-1, 1]) { |
| 25 | const sign = getSign(c); |
| 26 | const [i, j] = [x + sign, y + shift]; |
| 27 | if ( |
| 28 | V.OnBoard(i, j) && |
| 29 | this.getPiece(i, j) == V.PAWN && |
| 30 | this.getColor(i, j) == c |
| 31 | ) { |
| 32 | res += sign; |
| 33 | } |
| 34 | } |
| 35 | } |
| 36 | // Other pieces (sliders): |
| 37 | V.steps[V.ROOK].concat(V.steps[V.BISHOP]).forEach(s => { |
| 38 | let [i, j] = [x + s[0], y + s[1]]; |
| 39 | let compatible = [V.QUEEN]; |
| 40 | compatible.push(s[0] == 0 || s[1] == 0 ? V.ROOK : V.BISHOP); |
| 41 | let firstCol = undefined; |
| 42 | while (V.OnBoard(i, j)) { |
| 43 | if (this.board[i][j] != V.EMPTY) { |
| 44 | if (!(compatible.includes(this.getPiece(i, j)))) break; |
| 45 | const colIJ = this.getColor(i, j); |
| 46 | if (!firstCol) firstCol = colIJ; |
| 47 | if (colIJ == firstCol) res += getSign(colIJ); |
| 48 | else break; |
| 49 | } |
| 50 | i += s[0]; |
| 51 | j += s[1]; |
| 52 | } |
| 53 | }); |
| 54 | return res; |
| 55 | } |
| 56 | |
| 57 | getPotentialMovesFrom([x, y]) { |
| 58 | let moves = super.getPotentialMovesFrom([x, y]); |
| 59 | const color = this.turn; |
| 60 | if (this.getPiece(x, y) == V.KING && this.underCheck(color)) |
| 61 | // The king under check can only move as usual |
| 62 | return moves; |
| 63 | // Remember current final squares to not add moves twice: |
| 64 | const destinations = {}; |
| 65 | const lastRank = (color == 'w' ? 0 : 7); |
| 66 | const piece = this.getPiece(x, y); |
| 67 | moves.forEach(m => destinations[m.end.x + "_" + m.end.y] = true); |
| 68 | for (let i=0; i<8; i++) { |
| 69 | for (let j=0; j<8; j++) { |
| 70 | if (this.board[i][j] == V.EMPTY && !destinations[i + "_" + j]) { |
| 71 | const sa = this.sumAttacks([i, j]); |
| 72 | if ( |
| 73 | ((color == 'w' && sa > 0) || (color == 'b' && sa < 0)) && |
| 74 | (piece != V.PAWN || i != lastRank) |
| 75 | ) { |
| 76 | moves.push(this.getBasicMove([x, y], [i, j])); |
| 77 | } |
| 78 | } |
| 79 | } |
| 80 | } |
| 81 | return moves; |
| 82 | } |
| 83 | |
| 84 | static get SEARCH_DEPTH() { |
| 85 | return 1; |
| 86 | } |
| 87 | }; |