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import { createElement, useEffect, useRef, useState } from 'react'import type { PropsWithChildren } from 'react'import type { Atom } from './atom'import { createScopeContainer, getScopeContext } from './contexts'import type { ScopeContainer } from './contexts'import { COMMIT_ATOM, createStoreForExport } from './store'import type { VersionObject } from './store'
type Scope = NonNullable<Parameters<typeof getScopeContext>[0]>
export const Provider = ({  children,  initialValues,  scope,  unstable_createStore,  unstable_enableVersionedWrite,}: PropsWithChildren<{  initialValues?: Iterable<readonly [Atom<unknown>, unknown]>  scope?: Scope  /**   * This is an unstable feature to use exported createStore.   */  unstable_createStore?: typeof createStoreForExport  /**   * This is an unstable experimental feature for React 18.   * When this is enabled, a) write function must be pure   * (read function must be pure regardless of this),   * b) React will show warning in DEV mode,   * c) then state branching works.   */  unstable_enableVersionedWrite?: boolean}>) => {  const [version, setVersion] = useState<VersionObject>({})  useEffect(() => {    const scopeContainer = scopeContainerRef.current as ScopeContainer    if (scopeContainer.w) {      scopeContainer.s[COMMIT_ATOM](null, version)      delete version.p      scopeContainer.v = version    }  }, [version])
  const scopeContainerRef = useRef<ScopeContainer>()  if (!scopeContainerRef.current) {    // lazy initialization    const scopeContainer = createScopeContainer(      initialValues,      unstable_createStore    )    if (unstable_enableVersionedWrite) {      let retrying = 0      scopeContainer.w = (write) => {        setVersion((parentVersion) => {          const nextVersion = retrying ? parentVersion : { p: parentVersion }          write(nextVersion)          return nextVersion        })      }      scopeContainer.v = version      scopeContainer.r = (fn) => {        ++retrying        fn()        --retrying      }    }    scopeContainerRef.current = scopeContainer  }
  const ScopeContainerContext = getScopeContext(scope)  return createElement(    ScopeContainerContext.Provider,    {      value: scopeContainerRef.current,    },    children  )}