import type { BaseContext } from "koa";
import qs from "qs";

export async function sleep(time: number) {
	return new Promise((resolve) => setTimeout(resolve, time));
}

export type Awaited<T> = T extends Promise<infer U> ? U : T;
export type UnwrapArray<T> = T extends Array<infer U> ? U : T;

export function* naturalNumbers(min: number, max: number) {
	for (let i = min; i <= max; i++) {
		yield i;
	}
}

export function UrlWithNewParams(
	ctx: BaseContext,
	query_params: Record<string, unknown>
): string {
	return `${ctx.path}?${qs.stringify(query_params)}`;
}

export function shuffle<T>(array: T[]): T[] {
	const array_copy = [...array];
	let currentIndex = array_copy.length;

	// While there remain elements to shuffle...
	while (currentIndex != 0) {
		// Pick a remaining element...
		const randomIndex = Math.floor(Math.random() * currentIndex);
		currentIndex--;

		// And swap it with the current element.
		[array_copy[currentIndex], array_copy[randomIndex]] = [
			array_copy[randomIndex],
			array_copy[currentIndex],
		];
	}
	return array_copy;
}