+import ChessRules from "/base_rules.js";
+import {ArrayFun} from "/utils/array.js";
+import {Random} from "/utils/alea.js";
+
+export default class DiamondRules extends ChessRules {
+
+ get hasFlags() {
+ return false;
+ }
+
+ get hasEnpassant() {
+ return false;
+ }
+
+ getSvgChessboard() {
+ const diagonal = 10 * this.size.y * Math.sqrt(2);
+ const halfDiag = 0.5 * diagonal;
+ const deltaTrans = 10 * this.size.y * (Math.sqrt(2) - 1) / 2;
+ let board = `
+ <svg
+ viewBox="0 0 ${diagonal} ${diagonal}"
+ class="chessboard_SVG">`;
+ board += `<g transform="rotate(45 ${halfDiag} ${halfDiag})
+ translate(${deltaTrans} ${deltaTrans})">`;
+ board += this.getBaseSvgChessboard();
+ board += "</g></svg>";
+ return board;
+ }
+
+ getPieceWidth(rwidth) {
+ return (0.95 * rwidth / (Math.sqrt(2) * this.size.y));
+ }
+
+ getPixelPosition(i, j, r) {
+ if (i < 0 || j < 0 || typeof i == "string")
+ return super.getPixelPosition(i, j, r);
+ const sqSize = this.getPieceWidth(r.width) / 0.95;
+ const flipped = this.flippedBoard;
+ i = (flipped ? this.size.x - 1 - i : i);
+ j = (flipped ? this.size.y - 1 - j : j);
+ const sq2 = Math.sqrt(2);
+ const shift = [- sqSize / 2, sqSize * (sq2 - 1) / 2];
+ const x = (j - i) * sqSize / sq2 + shift[0] + r.width / 2;
+ const y = (i + j) * sqSize / sq2 + shift[1];
+ return [r.x + x, r.y + y];
+ }
+
+ genRandInitBaseFen() {
+ if (this.options["randomness"] == 0) {
+ return {
+ fen: "krbp4/rqnp4/nbpp4/pppp4/4PPPP/4PPBN/4PNQR/4PBRK",
+ o: {}
+ };
+ }
+ let pieces = { w: new Array(8), b: new Array(8) };
+ for (let c of ["w", "b"]) {
+ if (c == 'b' && options.randomness == 1) {
+ pieces['b'] = pieces['w'];
+ break;
+ }
+ // Get random squares for every piece, totally freely
+ let positions = Random.shuffle(ArrayFun.range(8));
+ const composition = ['b', 'b', 'r', 'r', 'n', 'n', 'k', 'q'];
+ const rem2 = positions[0] % 2;
+ if (rem2 == positions[1] % 2) {
+ // Fix bishops (on different colors)
+ for (let i=2; i<8; i++) {
+ if (positions[i] % 2 != rem2) {
+ [positions[1], positions[i]] = [positions[i], positions[1]];
+ break;
+ }
+ }
+ }
+ for (let i = 0; i < 8; i++)
+ pieces[c][positions[i]] = composition[i];
+ }
+ const fen = (
+ pieces["b"].slice(0, 3).join("") + "p4/" +
+ pieces["b"].slice(3, 6).join("") + "p4/" +
+ pieces["b"].slice(6, 8).join("") + "pp4/" +
+ "pppp4/4PPPP/" +
+ "4PP" + pieces["w"].slice(6, 8).reverse().join("").toUpperCase() + "/" +
+ "4P" + pieces["w"].slice(3, 6).reverse().join("").toUpperCase() + "/" +
+ "4P" + pieces["w"].slice(0, 3).reverse().join("").toUpperCase());
+ return { fen: fen, o: {} };
+ }
+
+ pieces(color, x, y) {
+ let res = super.pieces(color, x, y);
+ const pawnShift = this.getPawnShift(color || 'w');
+ res['p'].moves = [{steps: [[pawnShift, pawnShift]], range: 1}];
+ res['p'].attack = [{steps: [[0, pawnShift], [pawnShift, 0]], range: 1}];
+ return res;
+ }
+
+};