import { InboxMessage } from '@trycourier/courier-js';
import { CourierToastDatastoreListener } from './toast-datastore-listener';
/**
 * Shared datastore for Courier toasts.
 *
 * This datastore listens to and stores Courier Inbox messages.
 *
 * @public
 */
export declare class CourierToastDatastore {
    /** Shared instance. Access via {@link CourierToastDatastore.shared}. */
    private static instance;
    /** FIFO stack of toast messages. The end of the array is index 0 of the stack. */
    private _dataset;
    /** Set of listeners whose handlers will be called when the datastore changes. */
    private _datastoreListeners;
    /** Cleanup function to remove the message event listener. */
    private _removeMessageEventListener?;
    /** The shared instance of CourierToastDatastore, used to access all public methods. */
    static get shared(): CourierToastDatastore;
    /**
     * Add a listener whose handlers are called when there are changes to the datastore.
     *
     * @param listener - an implementation of {@link CourierToastDatastoreListener}
     */
    addDatastoreListener(listener: CourierToastDatastoreListener): void;
    /**
     * Remove a previously added listener.
     *
     * Note: the `listener` param is matched by object reference, so callers must pass
     * the same object previously passed to {@link CourierToastDatastore.addDatastoreListener}.
     *
     * See also: {@link CourierToastDatastoreListener.remove}
     *
     * @param listener - a previously added listener implementation
     */
    removeDatastoreListener(listener: CourierToastDatastoreListener): void;
    /**
     * Start listening for toast messages.
     *
     * Calling this method will open a WebSocket connection to the Courier backend if one
     * is not already open.
     *
     * See also: {@link @trycourier/courier-js#Courier.shared.signIn} and {@link @trycourier/courier-js#Courier.shared.signOut}
     */
    listenForMessages(): Promise<void>;
    /**
     * Find the position of an {@link @trycourier/courier-js#InboxMessage} in the toast stack.
     *
     * Notes:
     *  - Since the stack is an array, with the last item being the "top" of the stack,
     *    a toast's position in the underlying array is the inverse of its stack position.
     *  - `message` is matched by {@link @trycourier/courier-js#InboxMessage.messageId}, not by object reference.
     *
     * @param message - the {@link @trycourier/courier-js#InboxMessage} to find in the stack
     */
    toastIndexOfMessage(message: InboxMessage): number;
    /**
     * Add an {@link @trycourier/courier-js#InboxMessage} toast item to the datastore.
     *
     * Calling this directly is useful to send test messages while developing with the Courier SDK.</p>
     *
     * @example
     * ```
     * CourierToastDatastore.shared.addMessage({
     *  title: 'Lorem ipsum dolor sit',
     *  body: 'Lorem ipsum dolor sit amet Lorem ipsum dolor sit amet',
     *  messageId: '1'
     * });
     * ```
     *
     * @param message - the message to add as a toast item.
     */
    addMessage(message: InboxMessage): void;
    /**
     * Remove an {@link @trycourier/courier-js#InboxMessage} from the datastore.
     *
     * Note: `message` is matched by {@link @trycourier/courier-js#InboxMessage.messageId}, not by object reference
     */
    removeMessage(message: InboxMessage): void;
    /** Access the shared instance with {@link CourierToastDatastore.shared}. */
    private constructor();
}