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import { Codec, metadata, ScaleAssertError, withMetadata } from "../mod.ts"import { transform } from "./transform.ts"
const encodeLookup = Array.from({ length: 256 }, (_, i) => i.toString(16).padStart(2, "0"))const decodeLookup = Array.from({ length: 128 }, (_, i) => parseInt(String.fromCharCode(i), 16) | 0)
export function encodeHex(bytes: Uint8Array): string {  let str = ""  for (let i = 0; i < bytes.length; i++) {    str += encodeLookup[bytes[i]!]  }  return str}
export function encodeHexPrefixed(bytes: Uint8Array) {  let str = "0x"  for (let i = 0; i < bytes.length; i++) {    str += encodeLookup[bytes[i]!]  }  return str}
export function decodeHex(hex: string): Uint8Array {  if (hex.startsWith("0x")) hex = hex.slice(2)  if (hex.length % 2 === 1) hex = "0" + hex  const array = new Uint8Array(hex.length >> 1)  for (let i = 0; i < array.length; i++) {    array[i] = (decodeLookup[hex.charCodeAt(i << 1)!]! << 4) | decodeLookup[hex.charCodeAt(i << 1 | 1)!]!  }  return array}
const hexRegex = /^(?:0x)?[\da-f]*$/iexport function hex($inner: Codec<Uint8Array>): Codec<string> {  return withMetadata(    metadata("$.hex", hex, $inner),    transform({      $base: $inner,      encode: decodeHex,      decode: encodeHex,      assert(assert) {        assert.typeof(this, "string")        if (!hexRegex.test(assert.value as string)) {          throw new ScaleAssertError(this, assert.value, `${assert.path}: invalid hex`)        }      },    }),  )}