/** State of one track() lease, independent of motion preference or fit-to-flow. */
export type AttachmentStatus = 'attaching' | 'active' | 'completed' | 'released' | 'failed';
export interface TrackOptions {
    /** Once per lease transition. Active follows successful measurement/output;
     * failed/released follow static settlement. Cleanup remains track()'s return. */
    onStatus?: (status: AttachmentStatus) => void;
    /** Write `--sv-view` (-1 below viewport → 0 in scene → 1 gone above). Default true. */
    view?: boolean;
    /** Write `--sv-t` (0..1 across the element's full travel through the viewport,
     * same semantics as the native `animation-timeline: view()` cover range). */
    travel?: boolean;
    /** Write `--sv-pin` (0..1 across the element's pinned stretch). The raw
     * fuel for curtains, horizontal carousels and any sticky choreography. */
    pin?: boolean | string;
    /** Sticky storytelling: split the element's pinned travel into N scenes.
     * Writes `--sv-scene` (0..N-1, eased + snapped) and fires onScene on integer changes. */
    scenes?: number;
    /** Scene snap dead-zone (0..1), false to disable. */
    snap?: number | false;
    /** Latch the live state once reached (entrance animations). */
    once?: boolean;
    onLive?: (live: boolean) => void;
    onScene?: (scene: number) => void;
    /** Fires when a [data-sv-fit] stage falls back to document flow. Discrete, not per frame. */
    onFlow?: (flow: boolean) => void;
    /** Fires every frame with the raw travel t (0..1). For video scrubbing,
     * WebGL cameras, or anything JS-driven. Keep the callback cheap. */
    onTravel?: (t: number) => void;
    /** Fires every frame with the raw pin progress (0..1 across the pinned
     * stretch). Frame scrubbing, camera tours. Implies pin tracking. */
    onPin?: (p: number) => void;
    /** Scroll container to measure against instead of the window viewport,
  * for tracked elements inside nested scroll panels. (The capture-phase
     * scroll listener already hears those scrolls; this makes the geometry
     * agree with them.) */
    root?: HTMLElement;
    /** Live-band enter line as a fraction of the viewport height (default 0.75). */
    enter?: number;
    /** Live-band exit line as a fraction of the viewport height (default 0.25). */
    exit?: number;
}
/** Internal lease status, deliberately absent from the package exports. */
export interface Attachment {
    state: AttachmentStatus;
    stop: () => void;
}
export declare function init(): boolean;
export declare function bootReleased(): boolean;
export declare function releaseBoot(): void;
/** Enable/disable document-wide --sv-page/--sv-v writes. Calling this at all
 * takes the decision away from auto-detection, permanently and in both
 * directions: pass true for a JS reader that no stylesheet reveals.
 * Repeated enabling does not schedule another frame. */
export declare function setPageOutputs(enabled: boolean): void;
export declare function settleUntracked(el: HTMLElement): void;
/** Track an element. Returns an untrack function. */
export declare function track(el: HTMLElement, opts?: TrackOptions): () => void;
export declare function attach(el: HTMLElement, opts?: TrackOptions): Attachment;
/** Force a recompute (e.g. after content changes outside a resize). */
export declare function refresh(): void;
/** Scroll so a Scenes container lands on the given scene. Pass the same
 * `root` the container is tracked with to scroll that element instead of the
 * window. Uses the rendered height, like the driver's pin math. */
export declare function scrollToScene(el: HTMLElement, index: number, count: number, smooth?: boolean, root?: HTMLElement): void;
export declare function prefersReducedMotion(): boolean;