project-transition-state.ts55 lines · main

1	export const FALLBACK_LONG_RUNNING_STATE_THRESHOLD_MINUTES = 10
2	// Persist long enough for same-browser reloads, but not so long that a later transition reuses stale state.
3	export const MAX_PERSISTED_TRANSITION_AGE_HOURS = 24
4
5	const MS_PER_MINUTE = 60 * 1000
6	const MS_PER_HOUR = 60 * MS_PER_MINUTE
7
8	export const minutesToMilliseconds = (minutes: number) => minutes * MS_PER_MINUTE
9	export const hoursToMilliseconds = (hours: number) => hours * MS_PER_HOUR
10
11	export const getPersistedTransitionStartTime = (
12	storageKey: string,
13	now = Date.now(),
14	maxAgeMs = Number.POSITIVE_INFINITY
15	) => {
16	if (typeof window === 'undefined') return now
17
18	const existingValue = window.localStorage.getItem(storageKey)
19
20	if (existingValue !== null) {
21	const parsedStartTime = Number(existingValue)
22	const elapsedMs = now - parsedStartTime
23
24	if (
25	Number.isFinite(parsedStartTime) &&
26	parsedStartTime > 0 &&
27	elapsedMs >= 0 &&
28	elapsedMs <= maxAgeMs
29	) {
30	return parsedStartTime
31	}
32	}
33
34	window.localStorage.setItem(storageKey, String(now))
35	return now
36	}
37
38	export const clearPersistedTransitionStartTime = (storageKey: string) => {
39	if (typeof window === 'undefined') return
40
41	window.localStorage.removeItem(storageKey)
42	}
43
44	export const getRemainingTransitionTimeMs = ({
45	startTimeMs,
46	thresholdMs,
47	now = Date.now(),
48	}: {
49	startTimeMs: number
50	thresholdMs: number
51	now?: number
52	}) => {
53	const elapsedMs = now - startTimeMs
54	return Math.max(thresholdMs - elapsedMs, 0)
55	}