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import { setProperty, unwrap, isWrappable, StoreNode, $RAW } from "./store.js";
const $ROOT = Symbol("store-root");
export type ReconcileOptions = {  key?: string | null;  merge?: boolean;};
function applyState(  target: any,  parent: any,  property: PropertyKey,  merge: boolean | undefined,  key: string | null) {  const previous = parent[property];  if (target === previous) return;  if (!isWrappable(target) || !isWrappable(previous) || (key && target[key] !== previous[key])) {    if (target !== previous) {      if (property === $ROOT) return target;      setProperty(parent, property, target);    }    return;  }
  if (Array.isArray(target)) {    if (target.length && previous.length && (!merge || (key && target[0][key] != null))) {      let i, j, start, end, newEnd, item, newIndicesNext, keyVal;      // common prefix      for (        start = 0, end = Math.min(previous.length, target.length);        start < end &&        (previous[start] === target[start] || (key && previous[start][key] === target[start][key]));        start++      ) {        applyState(target[start], previous, start, merge, key);      }
      const temp = new Array(target.length),        newIndices = new Map();      // common suffix      for (        end = previous.length - 1, newEnd = target.length - 1;        end >= start &&        newEnd >= start &&        (previous[end] === target[newEnd] || (key && previous[end][key] === target[newEnd][key]));        end--, newEnd--      ) {        temp[newEnd] = previous[end];      }
      // insert any remaining updates and remove any remaining nodes and we're done      if (start > newEnd || start > end) {        for (j = start; j <= newEnd; j++) setProperty(previous, j, target[j]);        for (; j < target.length; j++) {          setProperty(previous, j, temp[j]);          applyState(target[j], previous, j, merge, key);        }        if (previous.length > target.length) setProperty(previous, "length", target.length);        return;      }
      // prepare a map of all indices in target      newIndicesNext = new Array(newEnd + 1);      for (j = newEnd; j >= start; j--) {        item = target[j];        keyVal = key ? item[key] : item;        i = newIndices.get(keyVal);        newIndicesNext[j] = i === undefined ? -1 : i;        newIndices.set(keyVal, j);      }      // step through all old items to check reuse      for (i = start; i <= end; i++) {        item = previous[i];        keyVal = key ? item[key] : item;        j = newIndices.get(keyVal);        if (j !== undefined && j !== -1) {          temp[j] = previous[i];          j = newIndicesNext[j];          newIndices.set(keyVal, j);        }      }      // set all the new values      for (j = start; j < target.length; j++) {        if (j in temp) {          setProperty(previous, j, temp[j]);          applyState(target[j], previous, j, merge, key);        } else setProperty(previous, j, target[j]);      }    } else {      for (let i = 0, len = target.length; i < len; i++) {        applyState(target[i], previous, i, merge, key);      }    }    if (previous.length > target.length) setProperty(previous, "length", target.length);    return;  }
  const targetKeys = Object.keys(target);  for (let i = 0, len = targetKeys.length; i < len; i++) {    applyState(target[targetKeys[i]], previous, targetKeys[i], merge, key);  }  const previousKeys = Object.keys(previous);  for (let i = 0, len = previousKeys.length; i < len; i++) {    if (target[previousKeys[i]] === undefined) setProperty(previous, previousKeys[i], undefined);  }}
// Diff method for setStoreexport function reconcile<T extends U, U>(  value: T,  options: ReconcileOptions = {}): (state: U) => T {  const { merge, key = "id" } = options,    v = unwrap(value);  return state => {    if (!isWrappable(state) || !isWrappable(v)) return v;    const res = applyState(v, { [$ROOT]: state }, $ROOT, merge, key);    return res === undefined ? state as T : res as T;  };}
const producers = new WeakMap();const setterTraps: ProxyHandler<StoreNode> = {  get(target, property): any {    if (property === $RAW) return target;    const value = target[property];    let proxy;    return isWrappable(value)      ? producers.get(value) ||          (producers.set(value, (proxy = new Proxy(value, setterTraps))), proxy)      : value;  },
  set(target, property, value) {    setProperty(target, property, unwrap(value));    return true;  },
  deleteProperty(target, property) {    setProperty(target, property, undefined, true);    return true;  }};
// Immer style mutation styleexport function produce<T>(fn: (state: T) => void): (state: T) => T {  return state => {    if (isWrappable(state)) {      let proxy;      if (!(proxy = producers.get(state as Record<keyof T, T[keyof T]>))) {        producers.set(          state as Record<keyof T, T[keyof T]>,          (proxy = new Proxy(state, setterTraps))        );      }      fn(proxy);    }    return state;  };}