export function scrollIntoView(
container: HTMLElement,
selected: HTMLElement,
scrollPadding: number = 0,
): void {
if (!selected) {
container.scrollTop = 0
return
}
const offsetParents: HTMLElement[] = []
let pointer = selected.offsetParent
while (
pointer !== null &&
container !== pointer &&
container.contains(pointer)
) {
offsetParents.push(pointer as HTMLElement)
pointer = (pointer as HTMLElement).offsetParent
}
const top =
selected.offsetTop +
offsetParents.reduce((prev, curr) => prev + curr.offsetTop, 0)
const bottom = top + selected.offsetHeight
const viewRectTop = container.scrollTop + scrollPadding
const viewRectBottom =
container.scrollTop + container.clientHeight - scrollPadding
if (top < viewRectTop) {
container.scrollTop = top - scrollPadding
} else if (bottom > viewRectBottom) {
container.scrollTop = bottom - container.clientHeight + scrollPadding
}
}