import { MusterEvent, NodeDefinition, NodeLike, Params, StatefulGraphNode, StatefulNodeDefinition, StatefulNodeType } from '../../types/graph';
/**
 * An instance of the [[on]] node.
 * See the [[on]] documentation to find out more.
 */
export interface OnNode extends StatefulGraphNode<'on', OnNodeProperties, OnNodeState, OnNodeData> {
}
/**
 * A definition of the [[on]] node.
 * See the [[on]] documentation to find out more
 */
export interface OnNodeDefinition extends StatefulNodeDefinition<'on', OnNodeProperties, OnNodeState, OnNodeData> {
}
export declare type OnNodeCallback = (event: MusterEvent, props: Params) => NodeDefinition | undefined;
export interface OnNodeProperties {
    initialValue: NodeDefinition;
    callback: OnNodeCallback;
}
export interface OnNodeState {
    currentValue: NodeDefinition | undefined;
}
export interface OnNodeData {
    subscription: () => void;
}
/**
 * The implementation of the [[on]] node.
 * See the [[on]] documentation to find out more.
 */
export declare const OnNodeType: StatefulNodeType<'on', OnNodeProperties, OnNodeState>;
/**
 * Creates a new instance of an [[on]] node, which is a type of [[NodeDefinition]] which can react to the dispatched
 * Muster events. The node starts its lifecycle by emitting the `initialValue`.
 * This value can then be changed by the `callback` when a correct event has arrived. See the [[dispatch]]
 * documentation to learn more about dispatching events.
 *
 *
 * @example **Change the value on event**
 * ```ts
 * import muster, { dispatch, on, ref, value } from '@dws/muster';
 *
 * const app = muster({
 *   isOnline: on((event) => {
 *     if (event.type === 'online') return value(true);
 *     if (event.type === 'offline') return value(false);
 *     return undefined;
 *   }, true),
 * });
 *
 * app.resolve(ref('isOnline')).subscribe((isOnline) => {
 *   console.log(isOnline ? 'Online' : 'Offline');
 * });
 *
 * console.log('Dispatching `offline` event');
 * await app.resolve(dispatch('offline'));
 *
 * // Console output:
 * // Online
 * // Dispatching `offline` event
 * // Offline
 * ```
 */
export declare function on(callback: ((event: MusterEvent, params: Params) => NodeDefinition | NodeLike | undefined), initialValue: NodeDefinition | NodeLike): OnNodeDefinition;
export declare function isOnNodeDefinition(value: NodeDefinition): value is OnNodeDefinition;