import GcPdfViewer from "../GcPdfViewer";
import { ViewerOptions } from "../ViewerOptions";
import { IUndoStorage } from "./IUndoStorage";
import { UndoCommandSupport } from "./Commands/UndoCommandSupport";
/**
 * Command based undo state storage.
 **/
export declare class UndoStorage implements IUndoStorage {
    viewer: GcPdfViewer;
    skipCommandsHash: {
        [name: string]: boolean;
    };
    private _index;
    private _eventBus?;
    private _commandsList;
    private _undoInProgress;
    private _disabled;
    private _maxLevels;
    constructor(viewer: GcPdfViewer);
    /**
     * Apply undo storage options.
     * @param options
     */
    applyOptions(options: ViewerOptions): void;
    /**
     * Dispose undo storage.
     **/
    dispose(): void;
    /**
     * Clear undo storage.
     **/
    clear(): void;
    /**
     * Gets a value indicating whether the command specified in the command parameter is supported.
     * @param command
     **/
    isCommandSupported(command: UndoCommandSupport): boolean;
    /**
    * Execute a new command.
    * @param {type} command Instance of a command.
    * @returns {undefined}
    **/
    execute(command: UndoCommandSupport): Promise<void>;
    /**
     * Called after command action has been executed.
     * @param command
     */
    onCommandExecuted(command: UndoCommandSupport): void;
    /**
     * Undo last action.
     **/
    undo(): Promise<void>;
    /**
     * Redo next action.
     **/
    redo(): Promise<void>;
    /**
     * Gets a value indicating whether the undo storage can undo changes.
     **/
    get hasUndo(): boolean;
    /**
     * Gets a value indicating whether the undo storage can redo changes.
     **/
    get hasRedo(): boolean;
    /**
     * Gets current undo level index.
     **/
    get undoIndex(): number;
    /**
     * Gets total undo levels count.
     **/
    get undoCount(): number;
    /**
     * Gets a flag indicating whether an undo/redo or execute operation is in progress.
     **/
    get undoInProgress(): boolean;
    /**
     * Gets undo commands list. Used by FiltersPreviewPanel.
     * @ignore exclude from docs.
     **/
    get commands(): UndoCommandSupport[];
    applyOptionsInternal(options: Partial<ViewerOptions>, isInit?: boolean): void;
    private _init;
    private _onAddReplaceHighlights;
    private _legacyUndoCount;
    private _onLegacyUndoStorageChanged;
    private _reset;
}