/**
 * @module helpers/utils
 */

import { Dom } from 'jodit/core/dom/dom';
import type { Nullable } from 'jodit/types';

/**
 * @module helpers/utils
 */

export const inView = (
	elm: HTMLElement,
	root: HTMLElement,
	doc: Document
): boolean => {
	let rect = elm.getBoundingClientRect(),
		el: HTMLElement | null = elm as HTMLElement | null;

	const top: number = rect.top,
		height: number = rect.height;

	do {
		if (el && el.parentNode) {
			el = el.parentNode as HTMLElement;
			rect = el.getBoundingClientRect();

			if (!(top <= rect.bottom)) {
				return false;
			}

			// Check if the element is out of view due to a container scrolling
			if (top + height <= rect.top) {
				return false;
			}
		}
	} while (el && el !== root && el.parentNode);

	// Check its within the document viewport
	return (
		top <= ((doc.documentElement && doc.documentElement.clientHeight) || 0)
	);
};

export function scrollIntoViewIfNeeded(
	elm: Nullable<Node>,
	root: HTMLElement,
	doc: Document
): void {
	if (Dom.isHTMLElement(elm) && !inView(elm, root, doc)) {
		if (root.clientHeight !== root.scrollHeight) {
			root.scrollTop = elm.offsetTop;
		}

		if (!inView(elm, root, doc)) {
			elm.scrollIntoView();
		}
	}
}