chessgroundxx/dist/fen.js

lichess.org chess ui

import { pos2key, invRanks } from "./util.js";
import * as cg from "./types.js";
export const initial = "rnbakabnr/9/1c5c1/p1p1p1p1p/9/9/P1P1P1P1P/1C5C1/9/RNBAKABNR w";
const roles = {
    p: "pawn",
    r: "rook",
    n: "knight",
    b: "bishop",
    a: "advisor",
    c: "cannon",
    k: "king",
};
const letters = {
    pawn: "p",
    rook: "r",
    knight: "n",
    bishop: "b",
    advisor: "a",
    cannon: "c",
    king: "k",
};
export function read(fen) {
    if (fen === "start")
        fen = initial;
    if (fen.indexOf("[") !== -1)
        fen = fen.slice(0, fen.indexOf("["));
    const pieces = new Map();
    let row = fen.split("/").length;
    let col = 0;
    for (const c of fen) {
        switch (c) {
            case " ":
                return pieces;
            case "/":
                --row;
                if (row === 0)
                    return pieces;
                col = 0;
                break;
            case "~":
                // const piece = pieces.get(pos2key([col, row]));
                break;
            default:
                const nb = c.charCodeAt(0);
                if (nb < 58) {
                    col += c === "0" ? 9 : nb - 48;
                }
                else {
                    ++col;
                    const role = c.toLowerCase();
                    let piece = {
                        role: roles[role],
                        color: (c === role ? "black" : "white"),
                    };
                    pieces.set(pos2key([col, row]), piece);
                }
        }
    }
    return pieces;
}
export function write(pieces) {
    return invRanks
        .map((y) => cg.files
        .map((x) => {
        const piece = pieces.get((x + y));
        if (piece) {
            const letter = letters[piece.role];
            return piece.color === "white" ? letter.toUpperCase() : letter;
        }
        else
            return "1";
    })
        .join(""))
        .join("/")
        .replace(/1{2,}/g, (s) => s.length.toString());
}
//# sourceMappingURL=fen.js.map