import type { ScreenBox } from "./types.js";
/** Placement of an overlay relative to its anchor element's bounding box. */
export interface OverlayPosition {
    /** Distance (px) of the overlay's top edge below the element's top edge. */
    top?: number;
    /** Distance (px) of the overlay's bottom edge above the element's bottom edge. */
    bottom?: number;
    /** Distance (px) of the overlay's left edge right of the element's left edge. */
    left?: number;
    /** Distance (px) of the overlay's right edge left of the element's right edge. */
    right?: number;
}
/** Options for {@link OverlayManager.add}. */
export interface OverlayOptions {
    /** Where to anchor the overlay relative to the element. */
    position: OverlayPosition;
    /** Overlay content — an HTML string or a pre-built element. */
    html: string | HTMLElement;
    /** Zoom range in which the overlay is visible. */
    show?: {
        minZoom?: number;
        maxZoom?: number;
    };
    /**
     * Whether the overlay scales with zoom. `true` (default) scales 1:1 with the
     * diagram; `false` keeps a constant pixel size; an object clamps the scale.
     */
    scale?: boolean | {
        min?: number;
        max?: number;
    };
    /** Optional tag for bulk queries and removal. */
    type?: string;
}
/** A registered overlay. */
export interface Overlay {
    readonly id: string;
    readonly element: string;
    readonly type?: string;
    readonly node: HTMLElement;
}
/** Filter for {@link OverlayManager.get} / {@link OverlayManager.remove}. */
export interface OverlayFilter {
    element?: string;
    type?: string;
}
/** The host hooks an {@link OverlayManager} needs from a canvas or editor. */
export interface OverlayHost {
    /** The (position: relative) host element to mount the overlay layer into. */
    readonly hostEl: HTMLElement;
    /** Current zoom scale. */
    getScale(): number;
    /** Element bounding box in screen pixels relative to the host, or `null`. */
    getBBox(id: string): ScreenBox | null;
    /** Subscribes to viewport changes; returns an unsubscribe function. */
    onViewportChange(cb: () => void): () => void;
}
/**
 * Manages HTML overlays anchored to diagram elements. Overlays live in a
 * dedicated absolutely-positioned layer above the SVG and are repositioned on
 * every viewport change from the element's screen bounding box.
 */
export declare class OverlayManager {
    private readonly _host;
    private readonly _layer;
    private readonly _overlays;
    private readonly _unsub;
    private _counter;
    constructor(_host: OverlayHost);
    /** Adds an overlay anchored to `elementId`. Returns its overlay id. */
    add(elementId: string, opts: OverlayOptions): string;
    /** Removes an overlay by id, or all overlays matching a filter. */
    remove(idOrFilter: string | OverlayFilter): void;
    /** Returns overlays matching a filter (all overlays when omitted). */
    get(filter?: OverlayFilter): Overlay[];
    /** Removes every overlay. */
    clear(): void;
    /** Repositions all overlays from their elements' current bounding boxes. */
    reposition(): void;
    /** Removes the overlay layer and unsubscribes from viewport changes. */
    destroy(): void;
    private _repositionAll;
    private _position;
    private _scaleFactor;
}
//# sourceMappingURL=overlays.d.ts.map