/**
 * @module index
 * @packageDocumentation
 *
 * Main entry point - creates a YouTube web player style ambient glow behind videos.
 * Unlike YouTube's immersive player, this doesn't need a thumbnail spritesheet service.
 *
 * Modular structure:
 * - `lib/` - Internal modules (canvas, frame processing, event handling)
 * - `constants.ts` - Config constants
 * - `types.ts` - Type definitions
 */
import type { GlowOptions } from './types';
/**
 * Creates a YouTube web player style glow behind HTML5 videos.
 * Extracts colors from frames, blends them, and renders as a blurred backdrop.
 *
 * @example
 * ```typescript
 * const video = document.querySelector('video');
 * const glow = new AmbientGlow(video, {
 * blur: 96,
 * opacity: 0.65,
 * });
 *
 * video.play();
 * glow.destroy(); // when done
 * ```
 *
 * @public
 */
export declare class AmbientGlow {
    private readonly video;
    private readonly canvas;
    private readonly ctx;
    private readonly tempCanvas;
    private readonly tempCtx;
    private options;
    private lastImage;
    private isLooping;
    private animationFrameId;
    private lastUpdateTime;
    private resizeTimeout;
    private resizeRafId;
    private readonly boundHandlers;
    private isDestroyed;
    private resizeObserver;
    private intersectionObserver;
    private isVisible;
    private lastRect;
    /**
     * Creates a glow instance attached to a video element.
     *
     * @param video - Video element (must be in DOM with a parent).
     * @param options - Optional glow config. See {@link GlowOptions}.
     *
     * @throws {Error} If video has no parent or canvas context unavailable.
     *
     * @example
     * ```typescript
     * const video = document.querySelector('video');
     * const glow = new AmbientGlow(video, {
     *   blur: 120,
     *   opacity: 0.8,
     *   brightness: 1.2,
     * });
     * ```
     */
    constructor(video: HTMLVideoElement, options?: GlowOptions);
    /**
     * Normalizes options, converting responsiveness to blendOld/blendNew if set.
     *
     * @param options - Options to normalize.
     * @returns Normalized options with all required fields.
     * @private
     */
    private normalizeOptions;
    /**
     * Applies CSS filters (blur, brightness, etc.) to the canvas.
     * @private
     */
    private applyFilterStyles;
    /**
     * Sets up video/resize event listeners (stored for cleanup).
     * @private
     */
    private setupEventListeners;
    /**
     * Handles visibility changes from IntersectionObserver.
     * Pauses animation when out of view, resumes when back in view (if playing).
     * @private
     */
    private handleVisibilityChange;
    private handleLoadStart;
    private handleLoadedMetadata;
    private handleCanPlay;
    private handlePlay;
    private handleSeeked;
    private handlePause;
    private handleEnded;
    /**
     * Debounces resize events to avoid excessive canvas resizing.
     * Immediately updates canvas dimensions but defers expensive drawing.
     * @private
     */
    private debouncedResize;
    /**
     * Gets cached or fresh bounding rect dimensions for performance.
     * Only returns width and height, as that's all that's needed.
     * @private
     */
    private getCachedRect;
    /**
     * Resizes canvas to match video. Internal canvas is downscaled for perf,
     * CSS size is scaled up for the glow.
     * @private
     */
    private resizeCanvas;
    /**
     * Draws a video frame and blends with previous frame for smooth transitions.
     * Video readyState must be at least HAVE_CURRENT_DATA.
     * @private
     */
    private drawFrame;
    /**
     * Draws a video frame immediately without blending (ignores previous frame).
     * Used when video changes, is seeked, or playback resumes.
     * @private
     */
    private drawFrameImmediately;
    /**
     * Animation loop - updates glow at configured intervals.
     *
     * @param currentTime - Timestamp from requestAnimationFrame.
     * @private
     */
    private animationLoop;
    /**
     * Updates glow options on the fly.
     *
     * @param newOptions - Partial options to update (others stay unchanged).
     *
     * @example
     * ```typescript
     * glow.updateOptions({ blur: 120, opacity: 0.8 });
     * ```
     */
    updateOptions(newOptions: Partial<GlowOptions>): void;
    /**
     * Checks if glow has been destroyed.
     * @returns True if destroy() was called.
     */
    getIsDestroyed(): boolean;
    /**
     * Cleans up - stops animation, removes listeners, removes canvas from DOM.
     *
     * @example
     * ```typescript
     * glow.destroy();
     * ```
     */
    destroy(): void;
}
export type { GlowOptions, NormalizedGlowOptions } from './types';