// @ts-check

/**
 * Convert a `Uint8Array` to a URL-safe base64 string.
 * @param {Uint8Array} bytes
 * @returns {string}
 */
export const stringify = (bytes) => {
  const string = String.fromCharCode(...bytes);
  const base64 = btoa(string);
  return base64
    .replaceAll("+", "-")
    .replaceAll("/", "_")
    .replaceAll("=", "");
};

/**
 * Convert a URL-safe base64 string to a `Uint8Array`.
 * Returns `null` if the string is invalid.
 * @param {string} text
 * @returns {null | Uint8Array}
 */
export const parse = (text) => {
  const normalizedText = text
    .replaceAll("-", "+")
    .replaceAll("_", "/")
    .replaceAll(" ", "+");
  try {
    const string = atob(normalizedText);
    const bytes = new Uint8Array(string.length);
    for (let i = 0; i < string.length; i++) {
      bytes[i] = string.charCodeAt(i);
    }
    return bytes;
  } catch (_err) {
    return null;
  }
};