import { HTMLAttributes, RefObject } from 'react';
/**
 * The returned object from the `onChange` passed function, with the current state of
 * `added` and `removed` element ids.
 */
export type ChangesType = {
    added: string | null;
    removed: string | null;
};
/**
 * The react-use-navscroll configuration object
 */
export type useNavScrollArgs = {
    /**
     * Function called every time an element becomes active.
     * The changes object returned contains the "added" and "removed" id.
     * */
    onChange?: (changes: ChangesType) => void;
    /**
     * Pass an element as root to track a specific container, smaller than a viewport. Default is window (the whole viewport).
     * */
    root?: Element;
    /**
     * Moves the detection line by the amount of this offset, expressed in percentage. By default the value is 50 (center).
     * */
    offset?: number;
    /**
     * Declare if the detection should work vertically or horizontally. By default false (vertical)
     */
    isHorizontal?: boolean;
};
/**
 * The options object passed to the `register` function.
 */
export type RegisterOptions = {
    /**
     * Pass the string id of the parent element
     */
    parent?: string;
    /**
     * If the tracked element has already a reference, you can pass it and will be reused
     */
    ref?: RefObject<Element>;
};
/**
 * The attributes object to assign to the element to assign
 */
export type RegisteredAttributes<T extends Element> = {
    id: HTMLAttributes<T>['id'];
    ref: RefObject<T> | null;
};
/**
 * The object returned by the hook.
 */
export type useNavScrollResult = {
    /**
     * The function used to register the component into the tracking system.
     * It returns the id already passed and the reference object.
     * Note that only the reference value will be `null` in a SSR context.
     */
    register: <T extends Element>(id: string, options?: RegisterOptions) => RegisteredAttributes<T>;
    /**
     * Removes the given id from the tracking system.
     */
    unregister: (idToUnregister: string) => void;
    /**
     * A list of active ids (the full hierarchy).
     */
    activeIds: string[];
    /**
     * A convenience function to quickly check the active state for the given id
     */
    isActive: (id: string) => boolean;
    /**
     * A function to retrieve the reference of the current active element (only the last element, not the elements hierarchy).
     */
    getActiveRef: () => RefObject<Element> | null;
    /**
     * A list of active ids (the full hierarchy).
     */
    percentage: number;
};
export type TrackedElement = {
    id: string;
} & Required<Pick<RegisterOptions, 'ref'>> & Pick<RegisterOptions, 'parent'>;