import type { BytesLike } from '../types/UtilsTypes.js';
const ALPHABET = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
const ALPHABET_MAP = {} as Record<string, number>;

for (let i = 0; i < ALPHABET.length; i++) ALPHABET_MAP[ALPHABET.charAt(i)] = i;

const BASE = 58;

export function encode58(buffer: BytesLike | string) {
    if (buffer.length === 0) return '';

    let i: number;
    let j: number;

    const digits = [0];

    for (i = 0; i < buffer.length; i++) {
        for (j = 0; j < digits.length; j++) digits[j] <<= 8;

        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
        // @ts-ignore
        digits[0] += buffer[i];
        let carry = 0;

        for (j = 0; j < digits.length; ++j) {
            digits[j] += carry;
            carry = (digits[j] / BASE) | 0;
            digits[j] %= BASE;
        }

        while (carry) {
            digits.push(carry % BASE);
            carry = (carry / BASE) | 0;
        }
    }

    for (i = 0; buffer[i] === 0 && i < buffer.length - 1; i++) digits.push(0);

    return digits
        .reverse()
        .map((digit) => ALPHABET[digit])
        .join('');
}

export function decode58(string: string) {
    if (string.length === 0) return [];

    let i;
    let j;

    const bytes = [0];

    for (i = 0; i < string.length; i++) {
        const c: string = string[i];

        if (!(c in ALPHABET_MAP)) throw new Error('Non-base58 character');

        for (j = 0; j < bytes.length; j++) bytes[j] *= BASE;

        bytes[0] += ALPHABET_MAP[c];
        let carry = 0;

        for (j = 0; j < bytes.length; ++j) {
            bytes[j] += carry;
            carry = bytes[j] >> 8;
            bytes[j] &= 0xff;
        }

        while (carry) {
            bytes.push(carry & 0xff);
            carry >>= 8;
        }
    }

    for (i = 0; string[i] === '1' && i < string.length - 1; i++) bytes.push(0);

    return bytes.reverse();
}