Remember last visited page per section in localStorage

src/lib/lastVisited.ts

@@ -0,0 +1,51 @@
+/*
+ * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ */
+
+import { isLinkAccessible } from './layout';
+import type { Layout, Schema } from '@/types/schema';
+
+type CanGet = (prefix: string) => boolean;
+type HasPermission = (permission: string) => boolean;
+
+const STORAGE_KEY = 'stalwart-last-visited';
+
+// Stores the last visited view name for a given top-level section in localStorage.
+export function setLastVisitedSection(section: string, viewName: string): void {
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY);
+    const data = raw ? (JSON.parse(raw) as Record<string, string>) : {};
+    data[section] = viewName;
+    localStorage.setItem(STORAGE_KEY, JSON.stringify(data));
+  } catch {
+    // Ignore storage errors (e.g. private mode).
+  }
+}
+
+// Retrieves the last visited view name for a section, or null if none is stored.
+export function getLastVisitedSection(section: string): string | null {
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY);
+    if (!raw) return null;
+    const data = JSON.parse(raw) as Record<string, string>;
+    return data[section] ?? null;
+  } catch {
+    return null;
+  }
+}
+
+// Returns the stored view name only if it is still accessible in the target layout.
+export function findLastVisitedLinkInLayout(
+  schema: Schema,
+  layout: Layout,
+  edition: string,
+  canGet: CanGet,
+  hasPermission: HasPermission,
+): string | null {
+  const last = getLastVisitedSection(layout.name);
+  if (!last) return null;
+  if (isLinkAccessible(schema, last, edition, canGet, hasPermission)) return last;
+  return null;
+}