/**
 * Label manager.
 * @author Louis-Dominique Dubeau
 * @license MPL 2.0
 * @copyright Mangalam Research Center for Buddhist Languages
 */
/**
 * Maintains a mapping from HTML element id to labels meaningful to humans. Also
 * keeps a counter that can be used for assigning new ids to elements that don't
 * already have one.
 *
 */
export declare abstract class LabelManager {
    readonly name: string;
    /** A mapping of element id to allocated label. */
    protected _idToLabel: Record<string, string>;
    /**
     * A counter that must be incremented with each new label allocation. This
     * allows the allocation algorithm to know what the next label should be.
     */
    protected labelIndex: number;
    /**
     * @param name The name of this label manager. This is a convenience that can
     * be used to produce distinctive error messages, for instance.
     */
    constructor(name: string);
    /**
     * Allocate a label for an id. The relation between id and label remains
     * constant until [[deallocateAll]] is called.
     *
     * @param id The id of the element.
     *
     * @returns The allocated label. If the method is called multiple times with
     * the same ``id``, the return value must be the same. It may change only if
     * [[deallocateAll]] has been called between the calls to this method.
     */
    abstract allocateLabel(id: string): string;
    /**
     * Gets the label associated with an id.
     *
     * @param id The id.
     *
     * @returns The label. The value returned by this method obeys the same rules
     * as that of [[allocateLabel]] with the exception that if a call returned
     * ``undefined`` it may return another value on a subsequent call. (That is,
     * an ``id`` that did not have a label allocated to it may acquire such
     * label.)
     */
    idToLabel(id: string): string | undefined;
    /**
     * Deallocate all mappings between ids and labels. This will reset
     * [[_idToLabel]] to an empty map and [[labelIndex]] to 0.
     */
    deallocateAll(): void;
    /**
     * Clear out the labels that were allocated. This method is called by
     * [[deallocateAll]] to perform class-specific cleanup.
     */
    protected abstract _deallocateAllLabels(): void;
    /**
     * Gets the next number in the number sequence. This increments
     * [[labelIndex]].
     *
     * @returns The number.
     */
    nextNumber(): number;
}
/**
 * A label manager that associates alphabetical labels to each id given to
 * it. It will associate labels "a", "b", "c", ... up to "z" and then will
 * associate "aa", "bb", "cc", ... up to "zz", and continues repeating
 * characters each time it cycles over the alphabet.
 *
 * @param {string} name The name of this label manager.
 */
export declare class AlphabeticLabelManager extends LabelManager {
    allocateLabel(id: string): string;
    _deallocateAllLabels(): void;
}