/** @module run */

import { IContext } from "../context/IContext";
import { Parameters } from './Parameters';

/**
 * Helper class that notifies components.
 * 
 * [[INotifiable]]
 */
export class Notifier {
    /**
     * Notifies specific component.
     * 
     * To be notiied components must implement [[INotifiable]] interface.
     * If they don't the call to this method has no effect.
     * 
     * @param context     (optional) execution context to trace execution through call chain.
     * @param component         the component that is to be notified.
     * @param args              notifiation arguments.
     * 
     * @see [[INotifiable]]
     */
    public static notifyOne(context: IContext, component: any, args: Parameters): void {
        if (typeof component.notify === "function") {
            component.notify(context, args);
        }
    }

    /**
     * Notifies multiple components.
     * 
     * To be notified components must implement [[INotifiable]] interface.
     * If they don't the call to this method has no effect.
     * 
     * @param context     (optional) execution context to trace execution through call chain.
     * @param components         a list of components that are to be notified.
     * @param args              notification arguments.
     * 
     * @see [[notifyOne]]
     * @see [[INotifiable]]
     */
    public static notify(context: IContext, components: any[], args: Parameters): void {
        if (components == null) return;
        
        for (const component of components) {
            Notifier.notifyOne(context, component, args);
        }
    }
}