const overflow = [];
const nav = document.querySelector('nav');
const more = nav.children[nav.children.length - 1];
let navToggled = false;

function showMore() {
	more.text = more.text.replace("Less", "More");
	const itemHeight = nav.children[0].offsetHeight;

	if (!nav.contains(more)) {
		nav.appendChild(more);
	}

	while (overflow.length > 0 && nav.offsetHeight <= itemHeight) {
		nav.insertBefore(overflow.pop(), more);
	}

	while (nav.children.length > 0 && nav.offsetHeight > itemHeight) {
		overflow.push(nav.removeChild(nav.children[nav.children.length - 2]));
	}

	if (overflow.length == 0) {
		nav.removeChild(more);
	}

	navToggled = false;
}

function showAll() {
	while (overflow.length > 0) {
		nav.insertBefore(overflow.pop(), more);
	}

}

window.addEventListener('resize', showMore);
document.addEventListener('DOMContentLoaded', showMore);

function toggleNav() {
	if (navToggled = !navToggled) {
		more.text = more.text.replace("More", "Less");
		showAll();
	} else {
		more.text = more.text.replace("Less", "More");
		showMore();
	}
}

more.addEventListener("click", toggleNav);