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import { atom } from 'jotai'import type { WritableAtom } from 'jotai'import { RESET } from './constants'
export const NO_STORAGE_VALUE = Symbol()
type Unsubscribe = () => void
type SetStateActionWithReset<Value> =  | Value  | typeof RESET  | ((prev: Value) => Value | typeof RESET)
export interface AsyncStorage<Value> {  getItem: (key: string) => Promise<Value | typeof NO_STORAGE_VALUE>  setItem: (key: string, newValue: Value) => Promise<void>  removeItem: (key: string) => Promise<void>  delayInit?: boolean  subscribe?: (key: string, callback: (value: Value) => void) => Unsubscribe}
export interface SyncStorage<Value> {  getItem: (key: string) => Value | typeof NO_STORAGE_VALUE  setItem: (key: string, newValue: Value) => void  removeItem: (key: string) => void  delayInit?: boolean  subscribe?: (key: string, callback: (value: Value) => void) => Unsubscribe}
export interface AsyncStringStorage {  getItem: (key: string) => Promise<string | null>  setItem: (key: string, newValue: string) => Promise<void>  removeItem: (key: string) => Promise<void>}
export interface SyncStringStorage {  getItem: (key: string) => string | null  setItem: (key: string, newValue: string) => void  removeItem: (key: string) => void}
export function createJSONStorage<Value>(  getStringStorage: () => AsyncStringStorage): AsyncStorage<Value>
export function createJSONStorage<Value>(  getStringStorage: () => SyncStringStorage): SyncStorage<Value>
export function createJSONStorage<Value>(  getStringStorage: () => AsyncStringStorage | SyncStringStorage | undefined): AsyncStorage<Value> | SyncStorage<Value> {  let lastStr: string | undefined  let lastValue: any  const storage: AsyncStorage<Value> | SyncStorage<Value> = {    getItem: (key) => {      const parse = (str: string | null) => {        str = str || ''        if (lastStr !== str) {          try {            lastValue = JSON.parse(str)          } catch {            return NO_STORAGE_VALUE          }          lastStr = str        }        return lastValue      }      const str = getStringStorage()?.getItem(key) ?? null      if (str instanceof Promise) {        return str.then(parse)      }      return parse(str)    },    setItem: (key, newValue) =>      getStringStorage()?.setItem(key, JSON.stringify(newValue)),    removeItem: (key) => getStringStorage()?.removeItem(key),  }  if (    typeof window !== 'undefined' &&    typeof window.addEventListener === 'function'  ) {    storage.subscribe = (key, callback) => {      const storageEventCallback = (e: StorageEvent) => {        if (e.key === key && e.newValue) {          callback(JSON.parse(e.newValue))        }      }      window.addEventListener('storage', storageEventCallback)      return () => {        window.removeEventListener('storage', storageEventCallback)      }    }  }  return storage}
const defaultStorage = createJSONStorage(() =>  typeof window !== 'undefined'    ? window.localStorage    : (undefined as unknown as Storage))
export function atomWithStorage<Value>(  key: string,  initialValue: Value,  storage: AsyncStorage<Value> & { delayInit: true }): WritableAtom<Value, SetStateActionWithReset<Value>, Promise<void>>
export function atomWithStorage<Value>(  key: string,  initialValue: Value,  storage: AsyncStorage<Value>): WritableAtom<Promise<Value>, SetStateActionWithReset<Value>, Promise<void>>
export function atomWithStorage<Value>(  key: string,  initialValue: Value,  storage: SyncStorage<Value>): WritableAtom<Value, SetStateActionWithReset<Value>>
export function atomWithStorage<Value>(  key: string,  initialValue: Value): WritableAtom<Value, SetStateActionWithReset<Value>>
export function atomWithStorage<Value>(  key: string,  initialValue: Value,  storage:    | SyncStorage<Value>    | AsyncStorage<Value> = defaultStorage as SyncStorage<Value>) {  const getInitialValue = () => {    const value = storage.getItem(key)    if (value instanceof Promise) {      return value.then((v) => (v === NO_STORAGE_VALUE ? initialValue : v))    }    return value === NO_STORAGE_VALUE ? initialValue : value  }
  const baseAtom = atom(storage.delayInit ? initialValue : getInitialValue())
  baseAtom.onMount = (setAtom) => {    let unsub: Unsubscribe | undefined    if (storage.subscribe) {      unsub = storage.subscribe(key, setAtom)      // in case it's updated before subscribing      setAtom(getInitialValue())    }    if (storage.delayInit) {      const value = getInitialValue()      if (value instanceof Promise) {        value.then(setAtom)      } else {        setAtom(value)      }    }    return unsub  }
  const anAtom = atom(    (get) => get(baseAtom),    (get, set, update: SetStateActionWithReset<Value>) => {      const nextValue =        typeof update === 'function'          ? (update as (prev: Value) => Value | typeof RESET)(get(baseAtom))          : update
      if (nextValue === RESET) {        set(baseAtom, initialValue)        return storage.removeItem(key)      }
      set(baseAtom, nextValue)      return storage.setItem(key, nextValue)    }  )
  return anAtom}
// atomWithHash is implemented with atomWithStorage
export function atomWithHash<Value>(  key: string,  initialValue: Value,  options?: {    serialize?: (val: Value) => string    deserialize?: (str: string | null) => Value | typeof NO_STORAGE_VALUE    delayInit?: boolean    replaceState?: boolean    subscribe?: (callback: () => void) => () => void  }): WritableAtom<Value, SetStateActionWithReset<Value>> {  const serialize = options?.serialize || JSON.stringify  const deserialize =    options?.deserialize ||    ((str) => {      try {        return JSON.parse(str || '')      } catch {        return NO_STORAGE_VALUE      }    })  const subscribe =    options?.subscribe ||    ((callback) => {      window.addEventListener('hashchange', callback)      return () => {        window.removeEventListener('hashchange', callback)      }    })  const hashStorage: SyncStorage<Value> = {    getItem: (key) => {      if (typeof location === 'undefined') {        return NO_STORAGE_VALUE      }      const searchParams = new URLSearchParams(location.hash.slice(1))      const storedValue = searchParams.get(key)      return deserialize(storedValue)    },    setItem: (key, newValue) => {      const searchParams = new URLSearchParams(location.hash.slice(1))      searchParams.set(key, serialize(newValue))      if (options?.replaceState) {        history.replaceState(null, '', '#' + searchParams.toString())      } else {        location.hash = searchParams.toString()      }    },    removeItem: (key) => {      const searchParams = new URLSearchParams(location.hash.slice(1))      searchParams.delete(key)      if (options?.replaceState) {        history.replaceState(null, '', '#' + searchParams.toString())      } else {        location.hash = searchParams.toString()      }    },    ...(options?.delayInit && { delayInit: true }),    subscribe: (key, setValue) => {      const callback = () => {        const searchParams = new URLSearchParams(location.hash.slice(1))        const str = searchParams.get(key)        if (str !== null) {          setValue(deserialize(str))        } else {          setValue(initialValue)        }      }      return subscribe(callback)    },  }
  return atomWithStorage(key, initialValue, hashStorage)}