/** @module run */

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

/**
 * Helper class that executes components.
 * 
 * [[IExecutable]]
 */
export class Executor {
    /**
     * Executes specific component.
     * 
     * To be executed components must implement [[IExecutable]] 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 executed.
     * @param args              execution arguments.
     * @returns                 an execution result
     * 
     * @see [[IExecutable]]
     * @see [[Parameters]]
     */
    public static async executeOne(context: IContext, component: any, args: Parameters): Promise<any> {
        if (typeof component.execute === "function") {
            return await component.execute(context, args);
        }
    }

    /**
     * Executes multiple components.
     * 
     * To be executed components must implement [[IExecutable]] 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 executed.
     * @param args              execution arguments.
     * @returns                 an execution result
     * 
     * @see [[executeOne]]
     * @see [[IExecutable]]
     * @see [[Parameters]]
     */
    public static async execute(context: IContext, components: any[], args: Parameters): Promise<any[]> {
        const results: any[] = [];                

        for (const component of components) {
            const result = await Executor.executeOne(context, component, args)
            results.push(result);
        }

        return results;
    }
}