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import type { HexString } from '../types.ts';
const CHR = '0123456789abcdef';const U8 = new Uint8Array(256);const U16 = new Uint8Array(256 * 256);
for (let i = 0; i < CHR.length; i++) {  U8[CHR[i].charCodeAt(0) | 0] = i | 0;
  if (i > 9) {    U8[CHR[i].toUpperCase().charCodeAt(0) | 0] = i | 0;  }}
for (let i = 0; i < 256; i++) {  const s = i << 8;
  for (let j = 0; j < 256; j++) {    U16[s | j] = (U8[i] << 4) | U8[j];  }}
/** * @name hexToU8a * @summary Creates a Uint8Array object from a hex string. * @description * `null` inputs returns an empty `Uint8Array` result. Hex input values return the actual bytes value converted to a Uint8Array. Anything that is not a hex string (including the `0x` prefix) throws an error. * @example * <BR> * * ```javascript * import { hexToU8a } from 'https://deno.land/x/polkadot@0.2.40/util/mod.ts'; * * hexToU8a('0x80001f'); // Uint8Array([0x80, 0x00, 0x1f]) * hexToU8a('0x80001f', 32); // Uint8Array([0x00, 0x80, 0x00, 0x1f]) * ``` */export function hexToU8a (value?: HexString | string | null, bitLength = -1): Uint8Array {  if (!value) {    return new Uint8Array();  }
  let s = value.startsWith('0x')    ? 2    : 0;
  const decLength = Math.ceil((value.length - s) / 2);  const endLength = Math.ceil(    bitLength === -1      ? decLength      : bitLength / 8  );  const result = new Uint8Array(endLength);  const offset = endLength > decLength    ? endLength - decLength    : 0;
  for (let i = offset; i < endLength; i++, s += 2) {    // The big factor here is actually the string lookups. If we do    // HEX_TO_U16[value.substring()] we get an 10x slowdown. In the    // same vein using charCodeAt (as opposed to value[s] or value.charAt(s)) is    // also the faster operation by at least 2x with the character map above    result[i] = U16[(value.charCodeAt(s) << 8) | value.charCodeAt(s + 1)];  }
  return result;}