import { EventSourceBase, EventEmitter } from '@govflanders/vl-widget-event';
import { VersionAware } from '@govflanders/vl-widget-module';
import { PluginContext } from './context';
import { PluginHost } from './host';
import { PluginEvent } from './event';
import { PluginState } from './state';
import { PluginRuntime, PluginRuntimeAware } from './runtime';
/**
 * Interface which describes a plugin function hook.
 *
 * @todo Check whether we need to resolve this T to a specific type.
 */
export interface PluginHookFunction<T> {
    (...args: any[]): Promise<T>;
}
/**
 * Interface which describes a plugin.
 */
export interface Plugin<PluginHostType extends PluginHost = PluginHost, PluginContextType extends PluginContext = PluginContext, PluginRuntimeType extends PluginRuntime = PluginRuntime> extends EventEmitter, PluginRuntimeAware<PluginRuntimeType>, VersionAware {
    /**
     * Initialize the plugin.
     *
     * @return {Promise<void>}
     *   A promise to initialize the plugin.
     */
    initialize(): Promise<void>;
    /**
     * Get the current plugin state.
     *
     * @return {PluginState}
     *   Value which represents the current plugin state.
     */
    getPluginState(): PluginState;
    /**
     * Get the plugin host.
     *
     * @return {PluginHost}
     *   An object which represents the plugin host.
     */
    getPluginHost(): PluginHostType;
    /**
     * Get the plugin context.
     *
     * @return {PluginContext}
     *   An object which contains the plugin context.
     */
    getPluginContext(): PluginContextType;
    /**
     * Get the plugin type identifier.
     *
     * @return {string}
     *
     */
    getPluginTypeId(): string;
    /**
     * Get the plugin identifier.
     *
     * @return {string}
     */
    getPluginId(): string;
}
/**
 * Base implementation for a plugin.
 */
export declare abstract class PluginBase<PluginHostType extends PluginHost, PluginContextType extends PluginContext, PluginRuntimeType extends PluginRuntime> extends EventSourceBase implements Plugin<PluginHostType, PluginContextType, PluginRuntimeType> {
    /**
     * Holds the initialize promise.
     *
     * @var {PluginState}
     */
    protected pluginState: PluginState;
    /**
     * Holds a reference to the plugin host.
     *
     * @var {PluginHost}
     */
    protected pluginHost: PluginHostType;
    /**
     * Holds the plugin context.
     *
     * @var {PluginContext}
     */
    protected pluginContext: PluginContextType;
    /**
     * Holds the plugin initialization promise.
     *
     * @var {Promise<void>}
     */
    protected pluginInitPromise: Promise<void> | undefined;
    /**
     * Create a PluginBase object.
     *
     * @param {PluginHost} pluginHost
     *   An object which represents the plugin host.
     * @param {PluginContext} pluginContext
     *   An object which represents the widget context.
     *
     * @throws {Error}
     *   Indicates a widget context error.
     */
    constructor(pluginHost: PluginHostType, pluginContext: PluginContextType);
    /**
     * Handle task before initialization starts.
     *
     * @return {Promise<void>}
     *   A promise to perform the task.
     */
    protected onBeforeInitialize(): Promise<void>;
    /**
     * Handle task to initialize the plugin.
     *
     * @return {Promise<void>}
     *   A promise to perform the task.
     */
    protected onInitialize(): Promise<void>;
    /**
     * Handle task when plugin is about to transition to ready.
     *
     * @return {Promise<void>}
     *   A promise to perform the task.
     */
    protected onBeforeReady(): Promise<void>;
    /**
     * Handle task when plugin transitioned to ready.
     *
     * @return {Promise<void>}
     *   A promise to perform the task.
     */
    protected onReady(): Promise<void>;
    /**
     * Handle task when plugin transitioned to failure.
     *
     * @return {Promise<void>}
     *   A promise to perform the task.
     */
    protected onFailed(): Promise<void>;
    /**
     * Handle tasks when plugin triggers an error.
     *
     * @param {Error} error
     *   Error which was triggered.
     *
     * @return {Promise<void>}
     *   A promise to perform the task.
     */
    protected onError(error: Error): Promise<void>;
    /**
     * Create an event for given plugin hook.
     *
     * @param {string} hook
     *   Name of the hook.
     * @param {...any} args
     *   Additional hook arguments.
     *
     * @return {PluginEvent}
     *   An object which represents a plugin hook event.
     */
    protected createHookEvent(hook: string, ...args: any[]): PluginEvent;
    /**
     * Invoke specified hook for this plugin.
     *
     * @param {string} hook
     *   Name of the hook.
     * @param {...any} args
     *   Optional. Additional hook arguments.
     *
     * @return {Promise<void>}
     *   A promise to invoke a hook.
     */
    protected invokeHook(hook: string, ...args: any[]): Promise<void>;
    /**
     * Validate the plugin context.
     *
     * @param {PluginContext} pluginContext
     *   An object which represents the plugin context.
     *
     * @return {PluginContext}
     *   An object which represents the plugin context.
     *
     * @throws {Error}
     *   Indicates a context error.
     */
    protected validatePluginContext(pluginContext: PluginContextType): void;
    /**
     * {@inheritdoc}
     */
    initialize(): Promise<void>;
    /**
     * {@inheritdoc}
     */
    getPluginState(): PluginState;
    /**
     * {@inheritdoc}
     */
    getPluginHost(): PluginHostType;
    /**
     * {@inheritdoc}
     */
    getPluginContext(): PluginContextType;
    /**
     * {@inheritdoc}
     */
    getPluginTypeId(): string;
    /**
     * {@inheritdoc}
     */
    abstract getPluginId(): string;
    /**
     * {@inheritdoc}
     */
    abstract getRuntime(): PluginRuntimeType;
    /**
     * {@inheritdoc}
     */
    abstract getVersion(): string;
    /**
     * {@inheritdoc}
     */
    toString(): string;
}