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import { interpret } from 'xstate'import type {  AnyInterpreter,  AnyStateMachine,  AreAllImplementationsAssumedToBeProvided,  EventObject,  InternalMachineOptions,  InterpreterFrom,  InterpreterOptions,  Prop,  StateConfig,  StateFrom,} from 'xstate'import type { Atom, Getter, WritableAtom } from 'jotai'import { atom } from 'jotai'
export const RESTART = Symbol()
export interface MachineAtomOptions<TContext, TEvent extends EventObject> {  /**   * If provided, will be merged with machine's `context`.   */  context?: Partial<TContext>  /**   * The state to rehydrate the machine to. The machine will   * start at this state instead of its `initialState`.   */  state?: StateConfig<TContext, TEvent>}
type Options<TMachine extends AnyStateMachine> =  AreAllImplementationsAssumedToBeProvided<    TMachine['__TResolvedTypesMeta']  > extends false    ? InterpreterOptions &        MachineAtomOptions<TMachine['__TContext'], TMachine['__TEvent']> &        InternalMachineOptions<          TMachine['__TContext'],          TMachine['__TEvent'],          TMachine['__TResolvedTypesMeta'],          true        >    : InterpreterOptions &        MachineAtomOptions<TMachine['__TContext'], TMachine['__TEvent']> &        InternalMachineOptions<          TMachine['__TContext'],          TMachine['__TEvent'],          TMachine['__TResolvedTypesMeta']        >
type MaybeParam<T> = T extends (v: infer V) => unknown ? V : never
export function atomWithMachine<  TMachine extends AnyStateMachine,  TInterpreter = InterpreterFrom<TMachine>>(  getMachine: TMachine | ((get: Getter) => TMachine),  getOptions?: Options<TMachine> | ((get: Getter) => Options<TMachine>)): WritableAtom<  StateFrom<TMachine>,  MaybeParam<Prop<TInterpreter, 'send'>> | typeof RESTART,  void> {  const cachedMachineAtom = atom<{    machine: AnyStateMachine    service: AnyInterpreter  } | null>(null)  const machineAtom = atom(    (get) => {      const cachedMachine = get(cachedMachineAtom)      if (cachedMachine) {        return cachedMachine      }      let initializing = true      const safeGet = (a: Atom<unknown>) => {        if (initializing) {          return get(a)        }        throw new Error('get not allowed after initialization')      }      const machine = isGetter(getMachine) ? getMachine(safeGet) : getMachine      const options = isGetter(getOptions) ? getOptions(safeGet) : getOptions      initializing = false      const {        guards,        actions,        services,        delays,        context,        ...interpreterOptions      } = options || {}
      const machineConfig = {        ...(guards && { guards }),        ...(actions && { actions }),        ...(services && { services }),        ...(delays && { delays }),      }
      const machineWithConfig = machine.withConfig(        machineConfig as any,        () => ({          ...machine.context,          ...context,        })      )
      const service = interpret(machineWithConfig, interpreterOptions)      return { machine: machineWithConfig, service }    },    (get, set, _arg) => {      set(cachedMachineAtom, get(machineAtom))    }  )
  machineAtom.onMount = (commit) => {    commit()  }
  const cachedMachineStateAtom = atom<StateFrom<TMachine> | null>(null)
  const machineStateAtom = atom(    (get) =>      get(cachedMachineStateAtom) ??      (get(machineAtom).machine.initialState as StateFrom<TMachine>),    (get, set, registerCleanup: (cleanup: () => void) => void) => {      const { service } = get(machineAtom)      service.onTransition((nextState: any) => {        set(cachedMachineStateAtom, nextState)      })      service.start()      registerCleanup(() => {        const { service } = get(machineAtom)        service.stop()      })    }  )
  machineStateAtom.onMount = (initialize) => {    let unsub: (() => void) | undefined | false
    initialize((cleanup) => {      if (unsub === false) {        cleanup()      } else {        unsub = cleanup      }    })
    return () => {      if (unsub) {        unsub()      }      unsub = false    }  }
  const machineStateWithServiceAtom = atom(    (get) => get(machineStateAtom),    (      get,      set,      event: Parameters<AnyInterpreter['send']>[0] | typeof RESTART    ) => {      const { service } = get(machineAtom)      if (event === RESTART) {        service.stop()        set(cachedMachineAtom, null)        set(machineAtom, null)        const { service: newService } = get(machineAtom)        newService.onTransition((nextState: any) => {          set(cachedMachineStateAtom, nextState)        })        newService.start()      } else {        service.send(event)      }    }  )
  return machineStateWithServiceAtom}
const isGetter = <T>(v: T | ((get: Getter) => T)): v is (get: Getter) => T =>  typeof v === 'function'