export interface AuthState {
    token: string;
    userId: string;
    createdAt: string;
    expiresAt: string;
}
/**
 * Register a password for a user. Creates or updates the credential record.
 * Returns true on success, false if the user doesn't exist.
 */
export declare function registerPassword(userId: string, password: string): Promise<boolean>;
/**
 * Authenticate a user by email and password.
 * On success, creates an auth token, sets the user active, and returns the AuthState.
 * On failure, returns null.
 */
export declare function login(email: string, password: string): Promise<AuthState | null>;
/**
 * Log out the current user. Clears the auth token.
 */
export declare function logout(): void;
/**
 * Get the currently authenticated user (from the auth token).
 * Returns null if not authenticated or token expired.
 */
export declare function getAuthenticatedUser(): {
    userId: string;
    token: string;
} | null;
/**
 * Check whether a user has a password set.
 */
export declare function hasPassword(userId: string): boolean;
/**
 * Delete a user's credential record.
 */
export declare function deleteCredentials(userId: string): boolean;