/**
 * User-related utility functions
 */

const UNIQUE_ID_KEY = 'user_unique_id';
const USER_ID_KEY = 'user_id';

/**
 * Get or create a unique browser identifier
 */
export function getOrCreateUniqueId(): string {
  let uniqueId = localStorage.getItem(UNIQUE_ID_KEY);

  if (!uniqueId) {
    // Generate a UUID v4
    uniqueId = crypto.randomUUID();
    localStorage.setItem(UNIQUE_ID_KEY, uniqueId);
  }

  return uniqueId;
}

/**
 * Get user ID from localStorage
 */
export function getUserId(): string | null {
  return localStorage.getItem(USER_ID_KEY);
}

/**
 * Set user ID in localStorage
 */
export function setUserId(userId: string): void {
  localStorage.setItem(USER_ID_KEY, userId);
}

/**
 * Set user ID and notify components of authentication change
 * Use this when logging in or registering to ensure immediate UI updates
 */
export function setUserIdAndNotify(userId: string): void {
  setUserId(userId);
  // Dispatch custom event to immediately update all components using useAuth hook
  window.dispatchEvent(new CustomEvent('authChange'));
}

/**
 * Logout user by clearing data and notifying components
 * Use this when logging out to ensure immediate UI updates
 */
export function logoutAndNotify(): void {
  clearUserData();
  // Dispatch custom event to immediately update all components using useAuth hook
  window.dispatchEvent(new CustomEvent('authChange'));
}

/**
 * Clear user data from localStorage
 */
export function clearUserData(): void {
  localStorage.removeItem(USER_ID_KEY);
  localStorage.removeItem(UNIQUE_ID_KEY);
}

/**
 * Check if user is registered (has user_id)
 */
export function isUserRegistered(): boolean {
  return getUserId() !== null;
}