Files
tolaria/src/utils/frontendReady.ts
2026-05-01 04:58:44 +02:00

75 lines
1.9 KiB
TypeScript

export const FRONTEND_READY_EVENT_NAME = 'tolaria:frontend-ready'
export const STARTUP_RELOAD_ATTEMPT_KEY = 'tolaria:startup-reload-attempted'
declare global {
interface Window {
__tolariaFrontendReady?: boolean
}
}
type FrontendReadyOptions = {
storage?: Storage
win?: Window
}
type StartupReloadOptions = FrontendReadyOptions & {
reload?: () => void
}
function getSessionStorage(win: Window): Storage | null {
try {
return win.sessionStorage
} catch {
return null
}
}
function removeSessionItem(storage: Storage | null, key: string): void {
try {
storage?.removeItem(key)
} catch {
// Storage can be unavailable in hardened WebView/privacy modes.
}
}
function readSessionItem(storage: Storage | null, key: string): string | null {
try {
return storage?.getItem(key) ?? null
} catch {
return null
}
}
function writeSessionItem(storage: Storage | null, key: string, value: string): boolean {
try {
storage?.setItem(key, value)
return storage !== null
} catch {
return false
}
}
export function markFrontendReady(options: FrontendReadyOptions = {}): void {
const win = options.win ?? window
const storage = options.storage ?? getSessionStorage(win)
win.__tolariaFrontendReady = true
removeSessionItem(storage, STARTUP_RELOAD_ATTEMPT_KEY)
win.dispatchEvent(new Event(FRONTEND_READY_EVENT_NAME))
}
export function reloadFrontendOnceIfStartupFailed(
options: StartupReloadOptions = {},
): boolean {
const win = options.win ?? window
const storage = options.storage ?? getSessionStorage(win)
if (win.__tolariaFrontendReady === true) return false
if (readSessionItem(storage, STARTUP_RELOAD_ATTEMPT_KEY) === '1') return false
if (!writeSessionItem(storage, STARTUP_RELOAD_ATTEMPT_KEY, '1')) return false
const reload = options.reload ?? (() => win.location.reload())
reload()
return true
}