import { useEffect, useState, useCallback } from 'react'; import { isClient } from './util'; type Dispatch = (value: A) => void; type SetStateAction = S | ((prevState: S) => S); const noop = () => {}; const isUndefined = (value?: any): boolean => typeof value === 'undefined'; const useLocalStorage = ( key: string, initialValue?: T, raw?: boolean ): [T | undefined, Dispatch>, () => void] => { if (!isClient) { return [initialValue as T, noop, noop]; } const [state, setState] = useState(() => { try { const localStorageValue = localStorage.getItem(key); if (isUndefined(initialValue)) { return undefined; } if (typeof localStorageValue !== 'string') { localStorage.setItem(key, raw ? String(initialValue) : JSON.stringify(initialValue)); return initialValue; } return raw ? localStorageValue : JSON.parse(localStorageValue || 'null'); } catch { // If user is in private mode or has storage restriction // localStorage can throw. JSON.parse and JSON.stringify // can throw, too. return initialValue; } }); const remove = useCallback(() => { try { localStorage.removeItem(key); setState(undefined); } catch { // If user is in private mode or has storage restriction // localStorage can throw. } }, [key, setState]); useEffect(() => { if (isUndefined(state)) return; try { const serializedState = raw ? String(state) : JSON.stringify(state); localStorage.setItem(key, serializedState); } catch { // If user is in private mode or has storage restriction // localStorage can throw. Also JSON.stringify can throw. } }, [state]); return [state, setState, remove]; }; export default useLocalStorage;