import { ESLBaseElement } from '../../esl-base-element/core';
import type { DelegatedEvent, ESLIntersectionEvent } from '../../esl-event-listener/core';
import type { ESLAnchornavHierarchyBuilder } from './esl-anchornav.hierarchy';
/** {@link ESLAnchornav} item renderer */
export type ESLAnchornavRender = (data: ESLAnchorData, index: number, anchornav: ESLAnchornav) => string | Element;
/** {@link ESLAnchornav} anchor data interface */
export interface ESLAnchorData {
    id: string;
    title: string;
    data: Record<string, unknown>;
    $anchor: HTMLElement;
    parent?: string | null;
    children?: ESLAnchorData[];
}
/**
 * ESLAnchornav
 * @author Dmytro Shovchko
 *
 * ESLAnchornav is a component that collects content anchors from the page and provides anchor navigation
 */
export declare class ESLAnchornav extends ESLBaseElement {
    static is: string;
    static _renderers: Map<string, ESLAnchornavRender>;
    static _hierarchyBuilders: Map<string, ESLAnchornavHierarchyBuilder>;
    /** Gets renderer by name */
    static getRenderer(name: string): ESLAnchornavRender | undefined;
    /** Sets renderer */
    static setRenderer(renderer: ESLAnchornavRender): void;
    static setRenderer(name: string, renderer: ESLAnchornavRender): void;
    /** Gets hierarchy builder by name */
    static getHierarchyBuilder(name: string): ESLAnchornavHierarchyBuilder | undefined;
    /** Sets hierarchy builder */
    static setHierarchyBuilder(builder: ESLAnchornavHierarchyBuilder): void;
    static setHierarchyBuilder(name: string, builder: ESLAnchornavHierarchyBuilder): void;
    ACTIVECHANGED_EVENT: string;
    UPDATED_EVENT: string;
    protected INTERSECTION_THRESHOLD: number[];
    /** Item renderer which is used to build inner markup */
    rendererName: string;
    /** CSS classes to set on active item */
    activeClass: string;
    /** CSS classes to set on container when there are no anchors */
    emptyClass: string;
    /** Selector (ESLTraversingQuery) to find the container to apply empty class marker. Defaults to the component itself */
    emptyClassTarget: string;
    /** Selector (ESLTraversingQuery) to find anchor elements */
    anchorSelector: string;
    /** Grouping mode for building hierarchy: 'level' to group by the parsed `level` value from `esl-anchor` data, empty string for flat list */
    groupBy: string;
    protected _active: ESLAnchorData;
    protected _anchors: ESLAnchorData[];
    protected _flatAnchors: ESLAnchorData[];
    protected _items: Map<string, Element>;
    protected _offset: number;
    /** Active anchor */
    get active(): ESLAnchorData;
    set active(value: ESLAnchorData);
    /** Indicates whether the component has no anchors to display */
    get empty(): boolean;
    /** Anchors list (flattened for intersection observation) */
    protected get $anchors(): HTMLElement[];
    /** Anchornav offset */
    get offset(): number;
    set offset(value: number);
    /** Anchornav items container */
    protected get $itemsArea(): HTMLElement;
    /** Anchornav viewport (root element for IntersectionObservers checking visibility) */
    protected get $viewport(): Element | undefined;
    /** Permanent anchors to prepend to the list */
    protected get anchorsToPrepend(): ESLAnchorData[];
    /** Permanent anchors to append to the list */
    protected get anchorsToAppend(): ESLAnchorData[];
    /**
     * Finds anchor elements.
     * Uses {@link ESLTraversingQuery} syntax via {@link ESLBaseElement.$$findAll}.
     */
    protected findAnchors(): HTMLElement[];
    protected connectedCallback(): void;
    /**
     * Updates the component.
     * Performs a full refresh cycle: recollects anchors list and updates the UI state.
     * Use this method when the set/order of anchors may have changed.
     */
    update(): void;
    /** Builds the component anchors list markup */
    protected rerender(): void;
    /** Renders the component anchors list */
    protected renderAnchors(): Element[];
    /**
     * Renders a single anchor item using the specified or default renderer.
     * Registers the rendered element in the internal items map.
     * Use this method when rendering nested items to ensure proper registration.
     * @param data - anchor data to render
     * @param index - anchor index (optional)
     * @param renderer - custom renderer function (optional, uses rendererName by default)
     * @returns rendered element
     */
    renderItem(data: ESLAnchorData, index?: number, renderer?: ESLAnchornavRender): Element | undefined;
    /**
     * Gets anchor data from the anchor element
     * If resolved data is missing required fields (e.g., id), the anchor will be ignored.
     */
    protected getDataFrom($anchor: HTMLElement, index: number): ESLAnchorData | undefined;
    /**
     * Builds hierarchy from flat anchors list based on groupBy mode.
     * Override this method to implement custom hierarchy logic.
     * @param flatAnchors - flat list of anchors in DOM order
     * @returns hierarchical anchors list (roots only) or flat list if groupBy is empty
     */
    protected buildHierarchy(flatAnchors: ESLAnchorData[]): ESLAnchorData[];
    /**
     * Flattens hierarchical anchors list to a flat array in depth-first order.
     * @param anchors - hierarchical anchors list
     * @returns flat list of all anchors
     */
    protected flattenAnchors(anchors: ESLAnchorData[]): ESLAnchorData[];
    /** Gets initial active anchor */
    protected getInitialActive(): ESLAnchorData;
    /** Updates the active anchor */
    protected updateActiveAnchor(): void;
    /**
     * Updates active classes on navigation items.
     * Resets all active classes and sets the active class on the current item.
     * Override this method to implement custom active state logic (e.g., parent activation).
     * @param active - the active anchor
     */
    protected updateActiveClasses(active: ESLAnchorData): void;
    /**
     * Updates the container state based on whether anchors are present.
     * Sets the `empty` attribute on the component and applies `emptyClass` to the target element.
     */
    protected updateContainer(): void;
    /** Handles changing the active anchor */
    protected _onActiveChange(): void;
    /** Handles updating the component */
    protected _onUpdateEvent(): void;
    protected _onAnchornavRequest(): void;
    protected _onAnchorIntersection(e: ESLIntersectionEvent): void;
    protected _onAnchorClick(event: DelegatedEvent<MouseEvent>): void;
}
declare global {
    export interface ESLLibrary {
        Anchornav: typeof ESLAnchornav;
    }
    export interface HTMLElementTagNameMap {
        'esl-anchornav': ESLAnchornav;
    }
}