"use strict";

// TODO: Make separate package

const pTry = require("p-try");

module.exports = function pInterval(interval, handler) {
	let timer = setTimeout(doHandler, interval);

	function doHandler() {
		let startTime = Date.now();
		
		pTry(() => {
			return handler();
		}).then(() => {
			let timeElapsed = Date.now() - startTime();
	
			let timeout = (timeElapsed < interval)
				? interval - timeElapsed
				: 1; // Be consistently async!

			timer = setTimeout(doHandler, timeout);
		});
	}

	return function cancelInterval() {
		if (timer != null) {
			clearTimeout(timer);
			timer = null;
		}
	};
};