import { isHTMLElement } from './is.js';
export function focus(element) {
    if (isHTMLElement(element)) {
        element.focus();
    }
    else if (typeof element === 'string') {
        const el = document.querySelector(element);
        if (!el)
            return;
        el.focus();
    }
}
/**
 * Returns a list of nodes that can be in the tab sequence.
 * @see: https://developer.mozilla.org/en-US/docs/Web/API/TreeWalker
 */
export function getTabbableNodes(container) {
    const nodes = [];
    const walker = document.createTreeWalker(container, NodeFilter.SHOW_ELEMENT, {
        acceptNode: (node) => {
            // `.tabIndex` is not the same as the `tabindex` attribute. It works on the
            // runtime's understanding of tabbability, so this automatically accounts
            // for any kind of element that could be tabbed to.
            return node.tabIndex >= 0 ? NodeFilter.FILTER_ACCEPT : NodeFilter.FILTER_SKIP;
        },
    });
    while (walker.nextNode()) {
        nodes.push(walker.currentNode);
    }
    return nodes;
}
export function isHidden(el) {
    return el.offsetParent === null;
}