export const COMPANY_USER_ROLES = ['admin', 'user'];

/**
 * Validates a company user role.
 * @param {unknown} role
 * @returns {'admin'|'user'}
 * @throws {Error} 'Invalid role'
 */
export function assertRole(role) {
  if (!COMPANY_USER_ROLES.includes(role)) {
    throw new Error('Invalid role');
  }
  return role;
}

/**
 * Normalizes and validates an email address.
 * @param {unknown} email
 * @returns {string} lower-cased, trimmed email
 * @throws {Error} 'Invalid email'
 */
export function normalizeEmail(email) {
  const value = typeof email === 'string' ? email.trim().toLowerCase() : '';
  if (!value || !value.includes('@')) {
    throw new Error('Invalid email');
  }
  return value;
}