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import type { SetStoreFunction, Store } from "./store.js";
export const $RAW = Symbol("state-raw");
export function isWrappable(obj: any) {  return (    obj != null &&    typeof obj === "object" &&    (Object.getPrototypeOf(obj) === Object.prototype || Array.isArray(obj))  );}
export function unwrap<T>(item: T): T {  return item;}
export function setProperty(state: any, property: PropertyKey, value: any, force?: boolean) {  if (!force && state[property] === value) return;  if (value === undefined) {    delete state[property];  } else state[property] = value;}
function mergeStoreNode(state: any, value: any, force?: boolean) {  const keys = Object.keys(value);  for (let i = 0; i < keys.length; i += 1) {    const key = keys[i];    setProperty(state, key, value[key], force);  }}
function updateArray(  current: any,  next: Array<any> | Record<string, any> | ((prev: any) => Array<any> | Record<string, any>)) {  if (typeof next === "function") next = next(current);  if (Array.isArray(next)) {    if (current === next) return;    let i = 0,      len = next.length;    for (; i < len; i++) {      const value = next[i];      if (current[i] !== value) setProperty(current, i, value);    }    setProperty(current, "length", len);  } else mergeStoreNode(current, next);}
export function updatePath(current: any, path: any[], traversed: PropertyKey[] = []) {  let part,    next = current;  if (path.length > 1) {    part = path.shift();    const partType = typeof part,      isArray = Array.isArray(current);
    if (Array.isArray(part)) {      // Ex. update('data', [2, 23], 'label', l => l + ' !!!');      for (let i = 0; i < part.length; i++) {        updatePath(current, [part[i]].concat(path), traversed);      }      return;    } else if (isArray && partType === "function") {      // Ex. update('data', i => i.id === 42, 'label', l => l + ' !!!');      for (let i = 0; i < current.length; i++) {        if (part(current[i], i)) updatePath(current, [i].concat(path), traversed);      }      return;    } else if (isArray && partType === "object") {      // Ex. update('data', { from: 3, to: 12, by: 2 }, 'label', l => l + ' !!!');      const { from = 0, to = current.length - 1, by = 1 } = part;      for (let i = from; i <= to; i += by) {        updatePath(current, [i].concat(path), traversed);      }      return;    } else if (path.length > 1) {      updatePath(current[part], path, [part].concat(traversed));      return;    }    next = current[part];    traversed = [part].concat(traversed);  }  let value = path[0];  if (typeof value === "function") {    value = value(next, traversed);    if (value === next) return;  }  if (part === undefined && value == undefined) return;  if (part === undefined || (isWrappable(next) && isWrappable(value) && !Array.isArray(value))) {    mergeStoreNode(next, value);  } else setProperty(current, part, value);}
export function createStore<T>(state: T | Store<T>): [Store<T>, SetStoreFunction<T>] {  const isArray = Array.isArray(state);  function setStore(...args: any[]): void {    isArray && args.length === 1 ? updateArray(state, args[0]) : updatePath(state, args);  }  return [state as Store<T>, setStore];}
export function createMutable<T>(state: T | Store<T>): T {  return state as T;}
type ReconcileOptions = {  key?: string | null;  merge?: boolean;};
// Diff method for setStoreexport function reconcile<T extends U, U>(  value: T,  options: ReconcileOptions = {}): (state: U) => T {  return state => {    if (!isWrappable(state) || !isWrappable(value)) return value;    const targetKeys = Object.keys(value) as (keyof T)[];    for (let i = 0, len = targetKeys.length; i < len; i++) {      const key = targetKeys[i];      setProperty(state, key, value[key]);    }    const previousKeys = Object.keys(state) as (keyof T)[];    for (let i = 0, len = previousKeys.length; i < len; i++) {      if (value[previousKeys[i]] === undefined) setProperty(state, previousKeys[i], undefined);    }    return state as T;  };}
// Immer style mutation styleexport function produce<T>(fn: (state: T) => void): (state: T) => T {  return state => {    if (isWrappable(state)) fn(state);    return state;  };}