/**
 * Make sure two Uint8Arrays are deeply equivalent
 */
export function areEqual(array1: Uint8Array, array2: Uint8Array): boolean {
  if (array1.length != array2.length) {
    return false;
  }

  return array1.every((val, i) => val === array2[i]);
}

/**
 * Convert a Uint8Array to Hexadecimal.
 *
 * A replacement for `Buffer.toString('hex')`
 */
export function toHex(array: Uint8Array): string {
  const hexParts = Array.from(array, i => i.toString(16).padStart(2, '0'));

  // adce000235bcc60a648b0b25f1f05503
  return hexParts.join('');
}

/**
 * Convert a hexadecimal string to isoUint8Array.
 *
 * A replacement for `Buffer.from('...', 'hex')`
 */
export function fromHex(hex: string): Uint8Array {
  if (!hex) {
    return Uint8Array.from([]);
  }

  const isValid = hex.length !== 0 && hex.length % 2 === 0 && !/[^a-fA-F0-9]/u.test(hex);

  if (!isValid) {
    throw new Error('Invalid hex string');
  }

  const byteStrings = hex.match(/.{1,2}/g) ?? [];

  return Uint8Array.from(byteStrings.map(byte => parseInt(byte, 16)));
}

/**
 * Combine multiple Uint8Arrays into a single Uint8Array
 */
export function concat(arrays: Uint8Array[]): Uint8Array {
  let pointer = 0;
  const totalLength = arrays.reduce((prev, curr) => prev + curr.length, 0);

  const toReturn = new Uint8Array(totalLength);

  arrays.forEach(arr => {
    toReturn.set(arr, pointer);
    pointer += arr.length;
  });

  return toReturn;
}

/**
 * Convert bytes into a UTF-8 string
 */
export function toUTF8String(array: Uint8Array): string {
  const decoder = new globalThis.TextDecoder('utf-8');
  return decoder.decode(array);
}

/**
 * Convert a UTF-8 string back into bytes
 */
export function fromUTF8String(utf8String: string): Uint8Array {
  const encoder = new globalThis.TextEncoder();
  return encoder.encode(utf8String);
}

/**
 * Convert an ASCII string to Uint8Array
 */
export function fromASCIIString(value: string): Uint8Array {
  return Uint8Array.from(value.split('').map(x => x.charCodeAt(0)));
}

/**
 * Prepare a DataView we can slice our way around in as we parse the bytes in a Uint8Array
 */
export function toDataView(array: Uint8Array): DataView {
  return new DataView(array.buffer, array.byteOffset, array.length);
}