/**
 * User Manager - Handles user identity and properties
 *
 * Uses shared StorageManager for consistent storage operations.
 *
 * Manages:
 * - anonymous_id: Generated ID for anonymous users
 * - distinct_id: User-provided ID after identification
 * - device_id: Persistent device identifier
 * - user_properties: Custom properties set via identify/setUserProperties
 * - user_state: "anonymous" or "identified"
 */
import { UserIdentity, IdentityUpdate, PersistenceMethod } from "./types";
export declare class UserManager {
    private storage;
    private userIdentity;
    private _isFirstVisit;
    constructor(storageMethod?: PersistenceMethod, cross_subdomain?: boolean);
    /**
     * Hydrate identity from persistent storage.
     *
     * Called by VTilt._boot() once the browser environment is guaranteed ready
     * (DOMContentLoaded). This is the only code path that reads from
     * localStorage / cookies. If storage is empty (first visit), the generated
     * IDs are persisted so they survive the next page load.
     */
    hydrateFromStorage(): void;
    /**
     * Generate an ephemeral in-memory identity with no storage access.
     * Used by the constructor so the SDK is safe to instantiate in SSR.
     */
    private generateEphemeralIdentity;
    /**
     * Get current user identity
     */
    getUserIdentity(): UserIdentity;
    /**
     * Get current distinct ID (identified user ID)
     */
    getDistinctId(): string | null;
    /**
     * Get current anonymous ID
     */
    getAnonymousId(): string;
    /**
     * Get current user properties
     */
    getUserProperties(): Record<string, any>;
    /**
     * Get the effective ID for event tracking
     */
    getEffectiveId(): string;
    /**
     * Get current device ID
     */
    getDeviceId(): string;
    /**
     * Get current user state
     */
    getUserState(): "anonymous" | "identified";
    /**
     * Returns true if this is the user's first visit (no prior anonymous_id
     * in storage when the SDK booted). Resets after first call.
     * Matches GA4's _fv=1 semantics.
     */
    consumeFirstVisit(): boolean;
    /**
     * Apply batched identity changes with a single save.
     * Replaces individual setters to avoid multiple storage writes per operation.
     */
    applyUpdate(update: IdentityUpdate): void;
    /**
     * Reset identity to anonymous state. Generates new IDs and clears user data.
     */
    reset(resetDeviceId?: boolean): void;
    /**
     * Set initial person info
     */
    set_initial_person_info(maskPersonalDataProperties?: boolean, customPersonalDataProperties?: string[]): void;
    /**
     * Load user identity from storage.
     *
     * For traditional SSR websites where each page navigation reloads JavaScript,
     * identity MUST be persisted immediately when generated to ensure the same
     * anonymous_id is used across all page loads.
     *
     * Flow:
     * 1. Load from storage (reads cookies first for critical properties in SSR mode)
     * 2. Generate new IDs if not found
     * 3. Immediately persist to storage (saved to both localStorage and cookies)
     *
     * With `localStorage+cookie` persistence (default):
     * - Critical properties are stored in cookies for SSR compatibility
     * - Full data is stored in localStorage for fast SPA-style access
     * - Cookies ensure identity persists across full page reloads
     */
    private loadUserIdentity;
    /**
     * Save user identity to storage
     */
    private saveUserIdentity;
    /**
     * Get user properties from storage
     */
    private getStoredUserProperties;
    /**
     * Set user properties in storage
     */
    private setStoredUserProperties;
    /**
     * Register super properties once — a key is written only if it is not
     * already present. Mirrors PostHog's `persistence.register_once`: the value
     * is written to the **in-memory** identity (so it ships on the very next
     * event in this same page load, not only after a reload re-hydrates from
     * storage) and then persisted.
     */
    private register_once;
    private generateAnonymousId;
    private generateDeviceId;
    /**
     * Update storage method at runtime.
     */
    updateStorageMethod(method: PersistenceMethod, cross_subdomain?: boolean): void;
}