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const Numesis = require('numesis');
/** * @type {string} DEFAULT_CHARSET The default charset for USID */const DEFAULT_CHARSET = Numesis.DEFAULT;
/** * @param min The minimum number * @param max The maximum number * @returns A number between min and max */const randInt = (min, max) => parseInt(Math.random() * (max - min + 1) + min + "");
/** * @param len The length of the string * @param charset The charset for the string * @returns A random string with len length */const rand = (len = 3, charset = null) => {    charset = charset || DEFAULT_CHARSET;    const n = new Numesis(charset);    const c = n.charset.length;    const min = c ** (len - 1) - (len > 1 ? 0 : 1);    const max = c ** len - 1;    return n.e(randInt(min, max));};
/** * @param out_len The length of the output string * @param real_len The length of the initial int value to be encoded * @param charset The charset for the string * @returns A random string with out_len length */const uid = (out_len = 24, real_len = 18, charset = DEFAULT_CHARSET) => {    charset = charset || DEFAULT_CHARSET;    const n = new Numesis(charset);    let y = performance.now().toString();    y = (y.length < real_len ? y + "0".repeat(real_len - y.length - 1) + "1" : y).replace(".", "0");    let r = n.e(y);    return r.length < out_len ? r + rand(out_len - r.length) : r;};
/** *  * @param opts The options for the USID * @returns A callback function that generates an index based ID */const createIndex = (opts) => {        /**     * @return encoded latest index     */    return () => {                let { get, set, charset, min } = opts;        min = min || 0;        charset = charset || DEFAULT_CHARSET;        const n = new Numesis(opts.charset);        const lastIndex = get();        const index = lastIndex + 1;        set(index);        return n.t(min, index);    };};
module.exports = {    DEFAULT_CHARSET,    randInt,    rand,    uid,    createIndex};