/**
 * Copy/pasted from https://github.com/statelyai/xstate/blob/main/packages/xstate-react/src/stopRootWithRehydration.ts
 * and renamed to `stopActor`
 */

import type {AnyActorRef, Snapshot} from 'xstate'

const forEachActor = (
  actorRef: AnyActorRef,
  callback: (ref: AnyActorRef) => void,
) => {
  callback(actorRef)
  const children = actorRef.getSnapshot().children
  if (children) {
    Object.values(children).forEach((child) => {
      forEachActor(child as AnyActorRef, callback)
    })
  }
}

export function stopActor(actorRef: AnyActorRef) {
  // persist snapshot here in a custom way allows us to persist inline actors and to preserve actor references
  // we do it to avoid setState in useEffect when the effect gets "reconnected"
  // this currently only happens in Strict Effects but it simulates the Offscreen aka Activity API
  // it also just allows us to end up with a somewhat more predictable behavior for the users
  const persistedSnapshots: Array<[AnyActorRef, Snapshot<unknown>]> = []
  forEachActor(actorRef, (ref) => {
    persistedSnapshots.push([ref, ref.getSnapshot()])
    // muting observers allow us to avoid `useSelector` from being notified about the stopped snapshot
    // React reconnects its subscribers (from the useSyncExternalStore) on its own
    // and userland subscibers should basically always do the same anyway
    // as each subscription should have its own cleanup logic and that should be called each such reconnect
    ;(ref as any).observers = new Set()
  })
  const systemSnapshot = actorRef.system.getSnapshot?.()

  actorRef.stop()
  ;(actorRef.system as any)._snapshot = systemSnapshot
  persistedSnapshots.forEach(([ref, snapshot]) => {
    ;(ref as any)._processingStatus = 0
    ;(ref as any)._snapshot = snapshot
  })
}