/**
 * @license Copyright (c) 2003-2024, CKSource Holding sp. z o.o. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */
/**
 * @module core/pendingactions
 */
import ContextPlugin from './contextplugin.js';
import { type CollectionAddEvent, type CollectionRemoveEvent, type Observable } from '@ckeditor/ckeditor5-utils';
/**
 * The list of pending editor actions.
 *
 * This plugin should be used to synchronise plugins that execute long-lasting actions
 * (e.g. file upload) with the editor integration. It gives the developer who integrates the editor
 * an easy way to check if there are any actions pending whenever such information is needed.
 * All plugins that register a pending action also provide a message about the action that is ongoing
 * which can be displayed to the user. This lets them decide if they want to interrupt the action or wait.
 *
 * Adding and updating a pending action:
 *
 * ```ts
 * const pendingActions = editor.plugins.get( 'PendingActions' );
 * const action = pendingActions.add( 'Upload in progress: 0%.' );
 *
 * // You can update the message:
 * action.message = 'Upload in progress: 10%.';
 * ```
 *
 * Removing a pending action:
 *
 * ```ts
 * const pendingActions = editor.plugins.get( 'PendingActions' );
 * const action = pendingActions.add( 'Unsaved changes.' );
 *
 * pendingActions.remove( action );
 * ```
 *
 * Getting pending actions:
 *
 * ```ts
 * const pendingActions = editor.plugins.get( 'PendingActions' );
 *
 * const action1 = pendingActions.add( 'Action 1' );
 * const action2 = pendingActions.add( 'Action 2' );
 *
 * pendingActions.first; // Returns action1
 * Array.from( pendingActions ); // Returns [ action1, action2 ]
 * ```
 *
 * This plugin is used by features like {@link module:upload/filerepository~FileRepository} to register their ongoing actions
 * and by features like {@link module:autosave/autosave~Autosave} to detect whether there are any ongoing actions.
 * Read more about saving the data in the {@glink installation/getting-started/getting-and-setting-data Saving and getting data} guide.
 */
export default class PendingActions extends ContextPlugin implements Iterable<PendingAction> {
    /**
     * Defines whether there is any registered pending action.
     *
     * @readonly
     * @observable
     */
    hasAny: boolean;
    /**
     * A list of pending actions.
     */
    private _actions;
    /**
     * @inheritDoc
     */
    static get pluginName(): "PendingActions";
    /**
     * @inheritDoc
     */
    init(): void;
    /**
     * Adds an action to the list of pending actions.
     *
     * This method returns an action object with an observable message property.
     * The action object can be later used in the {@link #remove} method. It also allows you to change the message.
     *
     * @param message The action message.
     * @returns An observable object that represents a pending action.
     */
    add(message: string): PendingAction;
    /**
     * Removes an action from the list of pending actions.
     *
     * @param action An action object.
     */
    remove(action: PendingAction): void;
    /**
     * Returns the first action from the list or null if the list is empty
     *
     * @returns The pending action object.
     */
    get first(): PendingAction | null;
    /**
     * Iterable interface.
     */
    [Symbol.iterator](): Iterator<PendingAction>;
}
export interface PendingAction extends Observable {
    message: string;
}
/**
 * Fired when an action is added to the list.
 *
 * @eventName ~PendingActions#add
 * @param action The added action.
 */
export type PendingActionsAddEvent = CollectionAddEvent<PendingAction>;
/**
 * Fired when an action is removed from the list.
 *
 * @eventName ~PendingActions#remove
 * @param action The removed action.
 */
export type PendingActionsRemoveEvent = CollectionRemoveEvent<PendingAction>;