Timeout Task Scheduler

createTOScheduler.ts

import { isBrowser } from './browser';

type TOSchedulerId = number | string;
type TOSchedulerCallback = () => unknown;

const timeoutTask = (delay: number, callback: TOSchedulerCallback): () => void => {
  const scheduleId = setTimeout(() => callback(), delay);
  return () => clearTimeout(scheduleId);
};

declare function TOSchedulerStart (id: TOSchedulerId, time: number, callback: TOSchedulerCallback): void;
declare function TOSchedulerStart (time: number, callback: TOSchedulerCallback): void;

interface TOScheduler {
  stop: (id: TOSchedulerId) => void
  stopAll: () => void
  start: typeof TOSchedulerStart
  isPending: (id?: TOSchedulerId) => boolean
}

function createTOScheduler (): TOScheduler {
  const timeouts: Record<TOSchedulerId, TOSchedulerCallback> = {};

  const clean = (id: TOSchedulerId): void => {
    delete timeouts[id]; // eslint-disable-line @typescript-eslint/no-dynamic-delete
  };

  const stop = (id: TOSchedulerId): void => {
    timeouts[id]?.();
    clean(id);
  };

  const stopAll = (): void => {
    Object.keys(timeouts).forEach(stop);
  };

  const start = (a: TOSchedulerId | number, b: TOSchedulerCallback | number, c?: TOSchedulerCallback): void => {
    if (!isBrowser) {
      return;
    }

    const id = c ? a : '';
    const time = (c ? b : a) as number;
    const callback: () => unknown = c || b as TOSchedulerCallback;

    stop(id);
    timeouts[id] = timeoutTask(time, () => {
      clean(id);
      callback();
    });
  };

  const isPending = (id?: TOSchedulerId): boolean => {
    return timeouts[id ?? ''] !== undefined;
  };

  return Object.freeze({ stop, stopAll, start, isPending });
}

export type { TOScheduler };
export { createTOScheduler };