import { PriorityQueueStats } from './priority-queue';
import { HydrationBoundaryId, HydrationEventListener, HydrationEventType, HydrationMetricsSnapshot, HydrationPriority, HydrationSchedulerConfig, HydrationStatus, HydrationTask } from './types';
/**
 * Scheduler state for external observation.
 */
export interface SchedulerState {
    readonly isRunning: boolean;
    readonly isPaused: boolean;
    readonly isProcessing: boolean;
    readonly queueSize: number;
    readonly hydratedCount: number;
    readonly pendingCount: number;
    readonly failedCount: number;
}
/**
 * Core scheduler for auto-prioritized hydration.
 *
 * @example
 * ```typescript
 * const scheduler = new HydrationScheduler({ debug: true });
 *
 * scheduler.register({
 *   id: 'hero-section',
 *   priority: 'critical',
 *   trigger: 'immediate',
 *   hydrate: async () => { ... },
 * });
 *
 * scheduler.start();
 * ```
 */
export declare class HydrationScheduler {
    /** Configuration */
    private readonly config;
    /** Priority queue for pending tasks */
    private readonly queue;
    /** Registered boundaries */
    private readonly boundaries;
    /** Visibility observer */
    private visibilityObserver;
    /** Media query listeners */
    private readonly mediaListeners;
    /** Interaction replay manager */
    private readonly replayManager;
    /** Event listeners */
    private readonly eventListeners;
    /** Metrics storage */
    private readonly metrics;
    /** State */
    private isRunning;
    private isPaused;
    private isProcessing;
    private idleCallbackHandle;
    private animationFrameHandle;
    private startTime;
    private aboveFoldHydrationTime;
    private fullHydrationTime;
    /**
     * Creates a new HydrationScheduler.
     *
     * @param config - Scheduler configuration
     */
    constructor(config?: Partial<HydrationSchedulerConfig>);
    /**
     * Starts the hydration scheduler.
     * Begins processing queued tasks according to their priority and triggers.
     */
    start(): void;
    /**
     * Stops the hydration scheduler.
     * Pending tasks remain in queue but processing stops.
     */
    stop(): void;
    /**
     * Pauses the scheduler without clearing the queue.
     */
    pause(): void;
    /**
     * Resumes a paused scheduler.
     */
    resume(): void;
    /**
     * Disposes of all resources.
     * Call when unmounting the hydration system.
     */
    dispose(): void;
    /**
     * Registers a hydration task.
     *
     * @param task - The hydration task to register
     */
    register(task: HydrationTask): void;
    /**
     * Unregisters a hydration task.
     *
     * @param id - ID of the task to unregister
     */
    unregister(id: HydrationBoundaryId): void;
    /**
     * Updates the priority of a registered boundary.
     *
     * @param id - ID of the boundary
     * @param priority - New priority level
     */
    updatePriority(id: HydrationBoundaryId, priority: HydrationPriority): void;
    /**
     * Forces immediate hydration of a specific boundary.
     *
     * @param id - ID of the boundary to hydrate
     */
    forceHydrate(id: HydrationBoundaryId): Promise<void>;
    /**
     * Forces hydration of all registered boundaries.
     */
    forceHydrateAll(): Promise<void>;
    /**
     * Gets the status of a specific boundary.
     *
     * @param id - ID of the boundary
     * @returns The hydration status, or undefined if not found
     */
    getStatus(id: HydrationBoundaryId): HydrationStatus | undefined;
    /**
     * Gets the current scheduler state.
     */
    getState(): SchedulerState;
    /**
     * Gets queue statistics.
     */
    getQueueStats(): PriorityQueueStats;
    /**
     * Gets aggregated metrics snapshot.
     */
    getMetrics(): HydrationMetricsSnapshot;
    /**
     * Gets the scheduler configuration.
     */
    getConfig(): HydrationSchedulerConfig;
    /**
     * Adds an event listener.
     *
     * @param type - Event type to listen for
     * @param listener - Callback function
     * @returns Unsubscribe function
     */
    on(type: HydrationEventType, listener: HydrationEventListener): () => void;
    /**
     * Removes an event listener.
     */
    off(type: HydrationEventType, listener: HydrationEventListener): void;
    /**
     * Sets up trigger-specific behavior for a boundary.
     */
    private setupTrigger;
    /**
     * Observes visibility for a boundary.
     */
    private observeVisibility;
    /**
     * Sets up interaction trigger for a boundary.
     */
    private setupInteractionTrigger;
    /**
     * Sets up media query trigger for a boundary.
     */
    private setupMediaTrigger;
    /**
     * Enqueues a boundary for hydration.
     */
    private enqueue;
    /**
     * Schedules processing using appropriate callback.
     */
    private scheduleProcessing;
    /**
     * Cancels any scheduled processing.
     */
    private cancelScheduledProcessing;
    /**
     * Processes the queue with a deadline (for idle callback).
     */
    private processQueueWithDeadline;
    /**
     * Processes the queue with frame budget.
     */
    private processQueue;
    /**
     * Hydrates a single task.
     */
    private hydrateTask;
    /**
     * Records a hydration metric.
     */
    private recordMetric;
    /**
     * Checks if all boundaries are hydrated.
     */
    private checkFullHydration;
    /**
     * Initializes the IntersectionObserver for visibility-based hydration.
     */
    private initializeVisibilityObserver;
    /**
     * Handles visibility change for an element.
     */
    private handleVisibilityChange;
    /**
     * Emits an event to all listeners.
     */
    private emitEvent;
    /**
     * Debug logging helper.
     */
    private log;
}
/**
 * Gets or creates the global HydrationScheduler instance.
 *
 * @param config - Scheduler configuration (only used if creating new instance)
 * @returns The global HydrationScheduler instance
 */
export declare function getHydrationScheduler(config?: Partial<HydrationSchedulerConfig>): HydrationScheduler;
/**
 * Resets the global HydrationScheduler instance.
 * Primarily useful for testing.
 */
export declare function resetHydrationScheduler(): void;