import * as i0 from "@angular/core";
/**
 * Keeps a field overlay — a select panel, autocomplete list, date picker or time
 * picker — inside the bounds of the form it belongs to.
 *
 * Without this, the CDK positions these panels against the viewport, so a panel
 * that cannot fit below its field flips upward and is drawn over the form's
 * heading and pinned tab strip, visually escaping the form.
 *
 * Containment is expressed as a clip band published on the document element and
 * consumed by each overlay's stylesheet:
 *   --ieeesa-form-overlay-clip-top     distance from the viewport top to the band
 *   --ieeesa-form-overlay-clip-bottom  distance from the band to the viewport bottom
 * plus an `ieeesa-form-overlay-open` class that activates those rules.
 *
 * The band is the form's field area intersected with the space the form's own
 * pinned chrome leaves free, so a panel never covers the tab strip / step header
 * above it or the action bar below it. It is recalculated on scroll and resize:
 * the form scrolls with the page, so a band measured only when the panel opened
 * would drift and clip the panel away as the user scrolled.
 * @export
 * @class FormOverlayBoundsService
 */
export declare class FormOverlayBoundsService {
    private static readonly OPEN_CLASS;
    private static readonly CLIP_TOP_PROPERTY;
    private static readonly CLIP_BOTTOM_PROPERTY;
    /** Field areas an overlay can be contained within, most specific first. */
    private static readonly FIELD_AREA_SELECTORS;
    /** Chrome pinned above the field area, which a panel must not cover. */
    private static readonly PINNED_ABOVE_SELECTORS;
    /** Chrome pinned below the field area, which a panel must not cover. */
    private static readonly PINNED_BELOW_SELECTORS;
    private fieldArea?;
    private updateBand?;
    /**
     * Returns the form field area the given host element sits in, or null when the
     * host is not inside a form (a filter popover, a dialog) and so needs no
     * containment.
     * @param {HTMLElement} host
     * @return {(HTMLElement | null)}
     * @memberof FormOverlayBoundsService
     */
    getFieldArea(host: HTMLElement): HTMLElement | null;
    /**
     * Starts containing overlays to the form the host element belongs to, and keeps
     * the band current until `release` is called.
     * @param {HTMLElement} host
     * @return {(HTMLElement | null)} the field area, or null when not in a form
     * @memberof FormOverlayBoundsService
     */
    contain(host: HTMLElement): HTMLElement | null;
    /**
     * Returns the band an overlay is currently confined to, in viewport
     * coordinates. Callers use it to position a panel inside the form.
     * @return {({ top: number; bottom: number } | null)}
     * @memberof FormOverlayBoundsService
     */
    getBand(): {
        top: number;
        bottom: number;
    } | null;
    positionOverlayAboveField(host: HTMLElement, panelClass: string, triggerSelector: string): void;
    /**
     * Stops containing overlays and removes the published band, so unrelated
     * overlays are positioned normally.
     * @memberof FormOverlayBoundsService
     */
    release(): void;
    /**
     * Measures the usable band: the field area, trimmed by any of the form's own
     * chrome that is currently pinned over it.
     * @param {HTMLElement} fieldArea
     * @return {{ top: number; bottom: number }}
     * @memberof FormOverlayBoundsService
     */
    private measureBand;
    /**
     * Publishes the band as clip custom properties for the overlay stylesheets.
     * @param {HTMLElement} fieldArea
     * @memberof FormOverlayBoundsService
     */
    private publishBand;
    static ɵfac: i0.ɵɵFactoryDeclaration<FormOverlayBoundsService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<FormOverlayBoundsService>;
}