From 732d509b11d163e48095a81509df3ebb2ee0d8a2 Mon Sep 17 00:00:00 2001
From: Sam Potts <sam@potts.es>
Date: Tue, 10 Mar 2026 11:00:51 +1100
Subject: [PATCH] fix(sandbox): use simpler web storage hook (#794)

---
 .../sandbox/templates/utils/use-latest-ref.ts |  19 --
 .../templates/utils/use-web-storage.ts        | 169 ++----------------
 2 files changed, 12 insertions(+), 176 deletions(-)
 delete mode 100644 packages/sandbox/templates/utils/use-latest-ref.ts

diff --git a/packages/sandbox/templates/utils/use-latest-ref.ts b/packages/sandbox/templates/utils/use-latest-ref.ts
deleted file mode 100644
index 175e305c..00000000
--- a/packages/sandbox/templates/utils/use-latest-ref.ts
+++ /dev/null
@@ -1,19 +0,0 @@
-'use client';
-
-import { useRef } from 'react';
-
-/**
- * Keep a ref that always points to the latest value.
- *
- * Useful for capturing callbacks or derived values inside closures
- * that are created once (e.g. factory callbacks) without stale reads.
- */
-export function useLatestRef<Value>(value: Value): Readonly<{ current: Value }> {
-  const ref = useRef(value);
-  ref.current = value;
-  return ref;
-}
-
-export namespace useLatestRef {
-  export type Result<Value> = Readonly<{ current: Value }>;
-}
diff --git a/packages/sandbox/templates/utils/use-web-storage.ts b/packages/sandbox/templates/utils/use-web-storage.ts
index 740af2dc..1505a251 100644
--- a/packages/sandbox/templates/utils/use-web-storage.ts
+++ b/packages/sandbox/templates/utils/use-web-storage.ts
@@ -1,162 +1,17 @@
-import type { SetStateAction } from 'react';
-import { useEffect, useEffectEvent, useMemo, useState } from 'react';
+import { useState } from 'react';
+import {
+  createWebStorageStore,
+  type WebStorageSerializableValue,
+  type WebStorageType,
+} from './create-web-storage-store';
+import { useExternalStore } from './use-external-store';
 
-import { useLatestRef } from './use-latest-ref';
-
-type FallbackStorageInterface = Pick<Storage, 'getItem' | 'setItem' | 'removeItem'>;
-
-export class FallbackStorage implements FallbackStorageInterface {
-  private readonly state = new Map<string, string>();
-
-  public getItem(key: string): string | null {
-    return this.state.get(key) ?? null;
-  }
-
-  public setItem(key: string, value: string): void {
-    this.state.set(key, value);
-  }
-
-  public removeItem(key: string): void {
-    this.state.delete(key);
-  }
-}
-
-type SetUseWebStorageAction<S> = S | ((prevValue: S) => S);
-type Dispatch<A> = (value?: A) => void;
-export type WebStorageSerializableValue =
-  | string
-  | boolean
-  | number
-  | null
-  | Record<string, any>
-  | WebStorageSerializableValue[];
-
-export type WebStorageType = 'local' | 'session';
-export type WebStorage = Storage | FallbackStorage;
-
-export type UseWebStorageReturn<T extends WebStorageSerializableValue | undefined> = [
-  T,
-  Dispatch<SetUseWebStorageAction<T>>,
-  isSupported: boolean,
-];
-
-export type UseWebStorageOnChange<T extends WebStorageSerializableValue> = (value: T | undefined) => void;
-
-export type UseWebStorageOptions<T extends WebStorageSerializableValue> = {
-  onChange?: UseWebStorageOnChange<T>;
-  parser?: (value: unknown) => T;
-};
-
-/**
- * Use web storage with a similar API to React's `useState`.
- * @param type 'local' for localStorage, 'session' for sessionStorage
- * @param key string
- * @param defaultValue T
- * @param options UseWebStorageOptions<T>
- * @returns [getter, setter, isSupported: boolean]
- */
 export function useWebStorage<T extends WebStorageSerializableValue>(
   type: WebStorageType,
   key: string,
-  defaultValue: T,
-  options?: UseWebStorageOptions<T>
-): UseWebStorageReturn<T>;
-export function useWebStorage<T extends WebStorageSerializableValue>(
-  type: WebStorageType,
-  key: string,
-  defaultValue?: T,
-  options?: UseWebStorageOptions<T>
-): UseWebStorageReturn<T | undefined>;
-export function useWebStorage<T extends WebStorageSerializableValue>(
-  type: WebStorageType,
-  key: string,
-  defaultValue?: T,
-  options?: UseWebStorageOptions<T>
-): UseWebStorageReturn<T | undefined> {
-  const { onChange, parser = (item: unknown) => item as T } = options ?? {};
-
-  const [storage] = useState(() => {
-    try {
-      const webStorage = type === 'local' ? localStorage : sessionStorage;
-      const testKey = '_____test_____';
-      // Ensure we can set a value to test if storage is supported.
-      webStorage.setItem(testKey, new Date().toISOString());
-      webStorage.removeItem(testKey);
-      return webStorage;
-    } catch {
-      return new FallbackStorage();
-    }
-  });
-
-  // Keep a reference to the latest value in state and sync to local storage.
-  const [latestValue, _setLatestValue] = useState<T | undefined>(() => {
-    try {
-      const item = storage.getItem(key);
-      return item ? parser(JSON.parse(item)) : defaultValue;
-    } catch {
-      return defaultValue;
-    }
-  });
-  const setLatestValue = useLatestRef<Dispatch<SetStateAction<T | undefined>>>((value) => {
-    if (typeof value === 'function') {
-      _setLatestValue((prev) => value(prev) ?? defaultValue);
-    } else {
-      _setLatestValue(value ?? defaultValue);
-    }
-  });
-
-  const handleStorageChange = useEffectEvent((event: StorageEvent) => {
-    if (event.key !== key) return;
-    // Hopefully legacy logic - some entries will be the string 'undefined' because of a bug
-    // where we called setItem(key, undefined)
-    // That said, it can't hurt to be cautious
-    const newValue =
-      event.newValue && event.newValue !== 'undefined' ? parser(JSON.parse(event.newValue)) : defaultValue;
-    if (newValue !== latestValue) setStoredValue(newValue);
-  });
-
-  // Update state when local storage changes in another tab
-  useEffect(() => {
-    const abortController = new AbortController();
-    window.addEventListener('storage', handleStorageChange, { signal: abortController.signal });
-    return () => {
-      abortController.abort();
-    };
-  }, []);
-
-  const setStoredValue = useMemo<Dispatch<SetStateAction<T | undefined>>>(() => {
-    const updateStorage = (value: T | undefined) => {
-      try {
-        // JSON.stringify returns undefined for values like () => {} or Symbol('')
-        // Also, if a toJSON() method returns undefined, JSON.stringify will too.
-        const jsonValue = JSON.stringify(value) as string | undefined;
-        if (jsonValue === undefined) {
-          storage.removeItem(key);
-        } else {
-          storage.setItem(key, jsonValue);
-        }
-        onChange?.(value);
-      } catch {
-        // Fail silently.
-      }
-    };
-
-    return (value) => {
-      if (typeof value === 'function') {
-        _setLatestValue((prev) => {
-          const newValue = value(prev);
-          updateStorage(newValue);
-          return newValue;
-        });
-        return;
-      }
-      updateStorage(value);
-      setLatestValue.current(value);
-    };
-  }, [key, onChange, setLatestValue, storage]);
-
-  // We have to check the inverse as Storage is not available in SSR.
-  const isSupported = !(storage instanceof FallbackStorage);
-
-  return [latestValue, setStoredValue, isSupported];
+  defaultValue: T
+): [T, (value: T) => void] {
+  const [store] = useState(() => createWebStorageStore<T>(type, key, defaultValue));
+  const value = useExternalStore(store);
+  return [value, store.setValue];
 }