[Init] Initial commit - NetMesh terminal manager

infrastructure/persistence/localStorageAdapter.ts

@@ -0,0 +1,111 @@
+const safeParse = <T>(value: string | null): T | null => {
+  if (!value) return null;
+  try {
+    return JSON.parse(value) as T;
+  } catch {
+    return null;
+  }
+};
+
+export const LOCAL_STORAGE_ADAPTER_CHANGED_EVENT = 'netcatty:local-storage-adapter-changed';
+
+const pendingChangedKeys = new Set<string>();
+let emitChangedKeysTimer: ReturnType<typeof setTimeout> | null = null;
+
+function dispatchLocalStorageAdapterChanged(key: string): void {
+  try {
+    const target = globalThis as typeof globalThis & {
+      dispatchEvent?: (event: Event) => boolean;
+      CustomEvent?: typeof CustomEvent;
+    };
+    if (typeof target.dispatchEvent !== 'function' || typeof target.CustomEvent !== 'function') return;
+    target.dispatchEvent(new target.CustomEvent<{ key: string }>(
+      LOCAL_STORAGE_ADAPTER_CHANGED_EVENT,
+      { detail: { key } },
+    ));
+  } catch {
+    // ignore
+  }
+}
+
+function emitLocalStorageAdapterChanged(key: string): void {
+  pendingChangedKeys.add(key);
+  if (emitChangedKeysTimer) return;
+
+  // Defer same-window storage notifications so React render-phase writes do
+  // not synchronously trigger state updates in unrelated components.
+  emitChangedKeysTimer = setTimeout(() => {
+    emitChangedKeysTimer = null;
+    const keys = Array.from(pendingChangedKeys);
+    pendingChangedKeys.clear();
+    for (const changedKey of keys) {
+      dispatchLocalStorageAdapterChanged(changedKey);
+    }
+  }, 0);
+}
+
+/**
+ * Safely write to localStorage, catching QuotaExceededError.
+ * Returns true if the write succeeded, false if storage quota was exceeded.
+ */
+function safeSetItem(key: string, value: string): boolean {
+  try {
+    if (localStorage.getItem(key) === value) {
+      return true;
+    }
+    localStorage.setItem(key, value);
+    emitLocalStorageAdapterChanged(key);
+    return true;
+  } catch (err) {
+    if (
+      err instanceof DOMException &&
+      (err.name === 'QuotaExceededError' || err.code === 22)
+    ) {
+      console.warn(
+        `[localStorageAdapter] QuotaExceededError writing key "${key}" (${value.length} chars). Data was not persisted.`,
+      );
+      return false;
+    }
+    throw err; // Re-throw unexpected errors
+  }
+}
+
+export const localStorageAdapter = {
+  read<T>(key: string): T | null {
+    return safeParse<T>(localStorage.getItem(key));
+  },
+  write<T>(key: string, value: T): boolean {
+    const json = JSON.stringify(value);
+    return safeSetItem(key, json);
+  },
+  readString(key: string): string | null {
+    return localStorage.getItem(key);
+  },
+  writeString(key: string, value: string): boolean {
+    return safeSetItem(key, value);
+  },
+  readBoolean(key: string): boolean | null {
+    const value = localStorage.getItem(key);
+    if (value === null) return null;
+    if (value === "true") return true;
+    if (value === "false") return false;
+    return null;
+  },
+  writeBoolean(key: string, value: boolean): boolean {
+    return safeSetItem(key, value ? "true" : "false");
+  },
+  readNumber(key: string): number | null {
+    const value = localStorage.getItem(key);
+    if (!value) return null;
+    const num = parseInt(value, 10);
+    return isNaN(num) ? null : num;
+  },
+  writeNumber(key: string, value: number): boolean {
+    return safeSetItem(key, String(value));
+  },
+  remove(key: string) {
+    if (localStorage.getItem(key) === null) return;
+    localStorage.removeItem(key);
+    emitLocalStorageAdapterChanged(key);
+  },
+};