feat/node: Add hex-byte util fns (#1390)

* hex-byte fns

* fix lint

* rem0oved converter

bindings/nodejs/lib/utils/index.ts

@@ -4,3 +4,34 @@
 export * from './utf8';
 export * from './utils';
 export * from '../types/utils';
+
+/**
+ * Converts a byte array to a hexadecimal string.
+ *
+ * @param {Uint8Array} byteArray - The bytes to encode.
+ * @param {boolean} [prefix=false] - Whether to include the '0x' prefix in the resulting hexadecimal string.
+ * @returns {string} The hexadecimal representation of the input byte array.
+ */
+export const bytesToHex = (bytes: ArrayLike<number>, prefix = false) => {
+    const hexArray = Array.from(bytes, (byte) =>
+        byte.toString(16).padStart(2, '0'),
+    );
+    const hexString = hexArray.join('');
+    return prefix ? '0x' + hexString : hexString;
+};
+
+/**
+ * Converts a hexadecimal string to a Uint8Array byte array.
+ *
+ * @param {string} hexString - The hexadecimal string to be converted.
+ * @returns {Uint8Array} The Uint8Array byte array representation of the input hexadecimal string.
+ * @throws {Error} Will throw an error if the input string is not a valid hexadecimal string.
+ */
+export const hexToBytes = (hexString: string) => {
+    const hex = hexString.replace(/^0x/, '');
+    const bytes = [];
+    for (let i = 0; i < hex.length; i += 2) {
+        bytes.push(parseInt(hex.substr(i, 2), 16));
+    }
+    return new Uint8Array(bytes);
+};

bindings/nodejs/lib/utils/utf8.ts

@@ -11,7 +11,7 @@ export const utf8ToBytes = (utf8: string) => {
 
 /** Convert hex encoded string to UTF8 string */
 export const hexToUtf8 = (hex: HexEncodedString) =>
-    decodeURIComponent(hex.replace('0x', '').replace(/[0-9a-f]{2}/g, '%$&'));
+    decodeURIComponent(hex.replace(/^0x/, '').replace(/[0-9a-f]{2}/g, '%$&'));
 
 /** Convert UTF8 string to hex encoded string */
 export const utf8ToHex = (utf8: string) =>