function getParentNode(node) {
    // document type
    if (node.nodeType === 9) {
        return null;
    }
    return node.parentNode;
}
export function getScrollParent(node) {
    if (node === null)
        return null;
    const parentNode = getParentNode(node);
    if (parentNode === null) {
        return null;
    }
    // Document
    if (parentNode.nodeType === 9) {
        return document.documentElement;
    }
    // Element
    if (parentNode.nodeType === 1) {
        // Firefox want us to check `-x` and `-y` variations as well
        const { overflow, overflowX, overflowY } = getComputedStyle(parentNode);
        if (/(auto|scroll|overlay)/.test(overflow + overflowY + overflowX)) {
            return parentNode;
        }
    }
    return getScrollParent(parentNode);
}