feat(filelib-web): 刷新页面时保持树展开、选中节点、tab 与文件夹位置

hub/filelib-web/src/lib/browser.ts

@@ -1,17 +1,62 @@
-import { writable } from "svelte/store";
+import { writable, get } from "svelte/store";
 import type { BreadcrumbEntry, NodeDetail } from "./types.js";
 
+const STORAGE_KEY = "filelib.browser";
+
+interface PersistedState {
+  expanded: string[];
+  currentNodeId: string | null;
+  tab: string | null;
+  selectedFilePath: string | null;
+}
+
+function loadPersisted(): PersistedState {
+  try {
+    const raw = sessionStorage.getItem(STORAGE_KEY);
+    if (raw) return JSON.parse(raw) as PersistedState;
+  } catch { /* ignore */ }
+  return { expanded: [], currentNodeId: null, tab: null, selectedFilePath: null };
+}
+
+function savePersisted(): void {
+  try {
+    const state: PersistedState = {
+      expanded: [...get(expanded)],
+      currentNodeId: get(currentNode)?.id ?? null,
+      tab: get(activeTab),
+      selectedFilePath: get(selectedFilePath),
+    };
+    sessionStorage.setItem(STORAGE_KEY, JSON.stringify(state));
+  } catch { /* sessionStorage 不可用时静默忽略 */ }
+}
+
+const persisted = loadPersisted();
+
 /** 树展开集合 / 当前选中节点 / 面包屑 / 树刷新计数。 */
-export const expanded = writable<Set<string>>(new Set());
+export const expanded = writable<Set<string>>(new Set(persisted.expanded));
 export const currentNode = writable<NodeDetail | null>(null);
 export const breadcrumb = writable<BreadcrumbEntry[]>([]);
 export const treeVersion = writable(0);
 
+/** 刷新后需要恢复的节点 ID;LibraryView onMount 消费后清空。 */
+export const restoreNodeId = persisted.currentNodeId;
+/** 刷新后需要恢复的 tab;NodeDetailPanel 消费。 */
+export const restoreTab = persisted.tab;
+
 /** 右侧预览栏:当前选中文件路径(项目内);切换节点时清空。 */
-export const selectedFilePath = writable<string | null>(null);
+export const selectedFilePath = writable<string | null>(persisted.selectedFilePath);
 /** 文件列表刷新计数(编辑器保存/删除后 bump,列表随之重载)。 */
 export const filesVersion = writable(0);
 
+/** 当前激活的 tab(由 NodeDetailPanel 写入,持久化用)。 */
+export const activeTab = writable<string | null>(persisted.tab);
+
+// 订阅需要持久化的 store,变化时写 sessionStorage。
+expanded.subscribe(() => savePersisted());
+currentNode.subscribe(() => savePersisted());
+selectedFilePath.subscribe(() => savePersisted());
+activeTab.subscribe(() => savePersisted());
+
 export function bumpTree(): void {
   treeVersion.update((v) => v + 1);
 }