Files
bsky-social-app/src/components/hooks/useFullscreen.ts
T
2026-01-16 17:20:03 -06:00

53 lines
1.6 KiB
TypeScript

import {
useCallback,
useEffect,
useRef,
useState,
useSyncExternalStore,
} from 'react'
import {IS_WEB, IS_WEB_FIREFOX, IS_WEB_SAFARI} from '#/env'
function fullscreenSubscribe(onChange: () => void) {
document.addEventListener('fullscreenchange', onChange)
return () => document.removeEventListener('fullscreenchange', onChange)
}
export function useFullscreen(ref?: React.RefObject<HTMLElement | null>) {
if (!IS_WEB) throw new Error("'useFullscreen' is a web-only hook")
const isFullscreen = useSyncExternalStore(fullscreenSubscribe, () =>
Boolean(document.fullscreenElement),
)
const scrollYRef = useRef<null | number>(null)
const [prevIsFullscreen, setPrevIsFullscreen] = useState(isFullscreen)
const toggleFullscreen = useCallback(() => {
if (isFullscreen) {
document.exitFullscreen()
} else {
if (!ref) throw new Error('No ref provided')
if (!ref.current) return
scrollYRef.current = window.scrollY
ref.current.requestFullscreen()
}
}, [isFullscreen, ref])
useEffect(() => {
if (prevIsFullscreen === isFullscreen) return
setPrevIsFullscreen(isFullscreen)
// Chrome has an issue where it doesn't scroll back to the top after exiting fullscreen
// Let's play it safe and do it if not FF or Safari, since anything else will probably be chromium
if (prevIsFullscreen && !IS_WEB_FIREFOX && !IS_WEB_SAFARI) {
setTimeout(() => {
if (scrollYRef.current !== null) {
window.scrollTo(0, scrollYRef.current)
scrollYRef.current = null
}
}, 100)
}
}, [isFullscreen, prevIsFullscreen])
return [isFullscreen, toggleFullscreen] as const
}