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import { snapshot, subscribe } from 'valtio/vanilla'import { atom } from 'jotai'import type { SetStateAction } from 'jotai'
const isObject = (x: unknown): x is object =>  typeof x === 'object' && x !== null
const applyChanges = <T extends object>(proxyObject: T, prev: T, next: T) => {  ;(Object.getOwnPropertyNames(prev) as (keyof T)[]).forEach((key) => {    if (!(key in next)) {      delete proxyObject[key]    } else if (Object.is(prev[key], next[key])) {      // unchanged    } else if (      isObject(proxyObject[key]) &&      isObject(prev[key]) &&      isObject(next[key])    ) {      applyChanges(        proxyObject[key] as unknown as object,        prev[key] as unknown as object,        next[key] as unknown as object      )    } else {      proxyObject[key] = next[key]    }  })  ;(Object.keys(next) as (keyof T)[]).forEach((key) => {    if (!(key in prev)) {      proxyObject[key] = next[key]    }  })}
type Options = {  sync?: boolean}
// Currently atomWithProxy does not support overwriting Promise() with a primitive// due to the requirement of valtio types to always be symmetric.// Consequently, this would not work:// setStatusState({ ...state, status: 'newStatus' })// To overwrite a value that came from a promise you must do it via an immediately// resolving promise:// setStatusState({ ...state, status: Promise.resolve('newStatus') })export function atomWithProxy<Value extends object>(  proxyObject: Value,  options?: Options) {  const baseAtom = atom(snapshot(proxyObject))  baseAtom.onMount = (setValue) => {    const callback = () => {      setValue(snapshot(proxyObject))    }    const unsub = subscribe(proxyObject, callback, options?.sync)    callback()    return unsub  }  const derivedAtom = atom(    (get) => get(baseAtom) as Value,    (get, _set, update: SetStateAction<Value>) => {      const newValue =        typeof update === 'function'          ? (update as (prev: Value) => Value)(get(baseAtom) as Value)          : update      applyChanges(proxyObject, snapshot(proxyObject) as Value, newValue)    }  )  return derivedAtom}