basepura/dist/index.js

Basepura encoder and decoder in TypeScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.REGEX = exports.CHARS = void 0;
exports.encode = encode;
exports.decode = decode;
exports.isBasepura = isBasepura;
exports.CHARS = "BCDGHJKLNPQRSTWZbcdghjklnpqrstwz";
exports.REGEX = /^[BCDGHJKLNPQRSTWZbcdghjklnpqrstwz]+$/;
const BASE = BigInt(exports.CHARS.length);
/**
 * Encodes a non-negative bigint into a Basepura string.
 *
 * @param n - A non-negative bigint to encode
 * @returns A Basepura string representation of the input number
 * @throws {RangeError} If the input is negative
 */
function encode(n) {
    if (n < 0n) {
        throw new RangeError("Input must be a non-negative integer.");
    }
    if (n === 0n) {
        return exports.CHARS[0];
    }
    let result = "";
    while (n > 0n) {
        result = exports.CHARS[Number(n % BASE)] + result;
        n /= BASE;
    }
    return result;
}
/**
 * Decodes a Basepura string into a bigint.
 *
 * @param s - A Basepura string to decode
 * @returns The decoded bigint value
 * @throws {RangeError} If the input is empty or contains invalid characters
 */
function decode(s) {
    if (s.length === 0) {
        throw new RangeError("Input must not be empty.");
    }
    let result = 0n;
    for (let i = 0; i < s.length; i++) {
        const index = exports.CHARS.indexOf(s[i]);
        if (index < 0) {
            throw new RangeError("Invalid character in input.");
        }
        result = result * BASE + BigInt(index);
    }
    return result;
}
/**
 * Checks if a string is a valid Basepura string.
 *
 * @param s - A string to validate
 * @returns True if the string contains only valid Basepura characters, false otherwise
 */
function isBasepura(s) {
    return exports.REGEX.test(s);
}