"use strict";

function findIdRoot(element) {
	let current = element;

	while (current != null) {
		if (current.id != null && current.id !== "") {
			return current;
		} else {
			current = current.parentElement;
		}
	}
}

module.exports = function generateSelector(element) {
	/* FIXME: check that element != null */
	let root = findIdRoot(element);

	if (root === element) {
		/* Special case: always identify by the ID alone, never suffix anything else, when the selected element *itself* has an ID. */
		return `#${element.id}`;
	} else {
		let segments = [
			(root != null) ? `#${root.id}` : null,
			(element.classList.length > 0)
				? Array.from(element.classList).map((className) => `.${className}`).join("")
				: element.tagName.toLowerCase()
		].filter((segment) => segment != null);
	
		return segments.join(" ");
	}
};