/**
 * Names of the custom events emitted by an `A11yDialog` instance.
 *
 * Each event is dispatched as a `CustomEvent` from the dialog element. The
 * original DOM event that triggered the dialog change (for example a click or
 * key press) is exposed on `event.detail`.
 *
 * - `'show'`: fired when the dialog is requested to open
 * - `'hide'`: fired when the dialog is requested to close
 * - `'destroy'`: fired when the instance is about to be destroyed
 *
 * All events are cancelable: calling `event.preventDefault()` inside a
 * listener will prevent the default behavior (opening, closing or destroying
 * the dialog).
 */
export type A11yDialogEvent = 'show' | 'hide' | 'destroy';
/**
 * Convenience type alias for the public `A11yDialog` instance.
 *
 * Useful when you want to store or pass around a reference to an instance
 * created with `new A11yDialog(...)`.
 */
export type A11yDialogInstance = InstanceType<typeof A11yDialog>;
/**
 * Controls an accessible modal dialog bound to a single DOM element.
 *
 * An instance:
 * - Initialises the dialog element with the required HTML attributes
 *   (`aria-hidden`, `aria-modal`, `role="dialog"` by default, and `tabindex`).
 * - Keeps track of the element that had focus before the dialog was opened and
 *   restores focus when the dialog is closed.
 * - Traps focus within the dialog while it is open and closes it with the ESC
 *   key (except when `role="alertdialog"` or when an opened popover is
 *   present).
 * - Delegates click handling for openers and closers declared with
 *   `[data-a11y-dialog-show]` and `[data-a11y-dialog-hide]` attributes,
 *   including elements inside Shadow DOM trees.
 *
 * The dialog starts hidden (`aria-hidden="true"`). Call `show()` or activate an
 * opener to display it.
 */
export default class A11yDialog {
    private $el;
    private id;
    private previouslyFocused;
    /**
     * Whether this dialog is currently shown.
     *
     * This flag is updated by `show()` and `hide()` and should be treated as
     * read-only by consumers.
     */
    shown: boolean;
    /**
     * Create a new `A11yDialog` controller for the given dialog element.
     *
     * The element must either:
     * - have a unique `id`, or
     * - define a `data-a11y-dialog` attribute whose value is used as the
     *   instance identifier.
     *
     * That identifier is referenced by opener and closer elements using
     * `[data-a11y-dialog-show="<id>"]` and `[data-a11y-dialog-hide="<id>"]`.
     */
    constructor(element: HTMLElement);
    /**
     * Destroy the current instance (after making sure the dialog has been hidden)
     * and remove all associated listeners from dialog openers and closers
     */
    destroy(): this;
    /**
     * Show the dialog.
     *
     * This:
     * - updates ARIA attributes on the dialog (`aria-hidden` is removed),
     * - remembers the previously focused element to restore it on `hide()`,
     * - moves focus into the dialog (or maintains it when opened via a focus
     *   event),
     * - starts trapping focus within the dialog, and
     * - dispatches a cancelable `'show'` `CustomEvent` from the dialog element.
     *
     * If a listener for the `'show'` event calls `event.preventDefault()`, the
     * dialog will not be opened.
     *
     * Returns the instance to allow method chaining.
     */
    show(event?: Event): this;
    /**
     * Hide the dialog.
     *
     * This:
     * - sets `aria-hidden="true"` on the dialog,
     * - stops trapping focus and key listeners associated with this instance, and
     * - restores focus to the element that was active before `show()` was called
     *   (when possible).
     *
     * A cancelable `'hide'` `CustomEvent` is dispatched before closing. If a
     * listener calls `event.preventDefault()`, the dialog will remain open.
     *
     * Returns the instance to allow method chaining.
     */
    hide(event?: Event): this;
    /**
     * Register a new callback for the given event type
     */
    on(type: A11yDialogEvent, handler: EventListener, options?: AddEventListenerOptions): this;
    /**
     * Unregister an existing callback for the given event type
     */
    off(type: A11yDialogEvent, handler: EventListener, options?: AddEventListenerOptions): this;
    /**
     * Dispatch and return a custom event from the DOM element associated with
     * this dialog; this allows authors to listen for and respond to the events
     * in their own code
     */
    private fire;
    /**
     * Add a delegated event listener for when elememts that open or close the
     * dialog are clicked, and call `show` or `hide`, respectively
     */
    private handleTriggerClicks;
    /**
     * Private event handler used when listening to some specific key presses
     * (namely ESC and TAB)
     */
    private bindKeypress;
    /**
     * If the dialog is shown and the focus is not within a dialog element (either
     * this one or another one in case of nested dialogs) or an element with the
     * ignore attribute, move it back to the dialog container
     * See: https://github.com/KittyGiraudel/a11y-dialog/issues/177
     */
    private maintainFocus;
}