promises.ts

import pMinDelay from "p-min-delay";

/**
 * Setting up a minimum wait time allows users
 * to visually grasp the text before it goes away, if
 * the task was faster than the minimum wait time.
 */
const MIN_TIME_BETWEEN_STEPS_MS = 500;

/**
 * Waits at least {@link MIN_TIME_BETWEEN_STEPS_MS} before resolving.
 */
export function minDelay(): Promise<void>;

/**
 * Executes the callback, and waits at least {@link MIN_TIME_BETWEEN_STEPS_MS} before resolving.
 */
export function minDelay<T>(callback: () => PromiseLike<T>): Promise<T>;

/**
 * Waits for the given promise, with a minimum wait of at least {@link MIN_TIME_BETWEEN_STEPS_MS}.
 */
export function minDelay<T>(promise: PromiseLike<T>): Promise<T>;

export function minDelay<T>(
	promiseOrCallback?: PromiseLike<T> | (() => PromiseLike<T>),
): Promise<T> {
	return pMinDelay(
		typeof promiseOrCallback === "function"
			? promiseOrCallback()
			: (promiseOrCallback ?? (Promise.resolve() as Promise<T>)),
		MIN_TIME_BETWEEN_STEPS_MS,
	);
}

/**
 * Extracts the resolved type from a Promise.
 */
export type UnwrapPromise<T> = T extends Promise<infer U> ? U : T;