feat(NotificationsPage): implement tabbed navigation for notifications and improve loading state handling

apps/portal/src/app/features/notifications/pages/NotificationsPage.tsx

@@ -1,3 +1,4 @@
+import { useState } from 'react';
 import { useNavigate } from 'react-router-dom';
 import {
   Badge,
@@ -7,6 +8,7 @@ import {
   Container,
   Group,
   Loader,
+  SegmentedControl,
   Stack,
   Text,
   Title,
@@ -15,9 +17,18 @@ import { IconBellOff, IconCheck } from '@tabler/icons-react';
 import {
   localized,
   useGetNotificationsQuery,
+  useGetUnseenNotificationsQuery,
   useMarkNotificationReadMutation,
 } from '@ema-platform/api';
 
+type Tab = 'all' | 'unseen' | 'seen';
+
+const EMPTY_COPY: Record<Tab, string> = {
+  all: 'No notifications yet.',
+  unseen: 'Nothing unread.',
+  seen: 'No read notifications.',
+};
+
 /**
  * The applicant's notification inbox.
  *
@@ -26,19 +37,15 @@ import {
  */
 export function NotificationsPage() {
   const navigate = useNavigate();
-  const { data, isLoading } = useGetNotificationsQuery();
+  const [tab, setTab] = useState<Tab>('all');
+  const all = useGetNotificationsQuery(undefined, { skip: tab === 'unseen' });
+  const unseen = useGetUnseenNotificationsQuery(undefined, { skip: tab !== 'unseen' });
   const [markRead] = useMarkNotificationReadMutation();
 
-  if (isLoading) {
-    return (
-      <Center h={300}>
-        <Loader />
-      </Center>
-    );
-  }
-
-  const items = data?.items ?? [];
-  const unread = items.filter((n) => !n.isSeen).length;
+  const { data, isLoading } = tab === 'unseen' ? unseen : all;
+  const items =
+    tab === 'seen' ? (data?.items ?? []).filter((n) => n.isSeen) : (data?.items ?? []);
+  const unread = all.data?.items.filter((n) => !n.isSeen).length ?? 0;
 
   async function open(id: string, seen: boolean, link?: string) {
     if (!seen) await markRead(id);
@@ -52,11 +59,27 @@ export function NotificationsPage() {
         {unread > 0 ? `${unread} unread` : 'You are all caught up'}
       </Text>
 
-      {items.length === 0 ? (
+      <SegmentedControl
+        size="xs"
+        mb="md"
+        value={tab}
+        onChange={(v) => setTab(v as Tab)}
+        data={[
+          { label: 'All', value: 'all' },
+          { label: 'Unseen', value: 'unseen' },
+          { label: 'Seen', value: 'seen' },
+        ]}
+      />
+
+      {isLoading ? (
+        <Center h={300}>
+          <Loader />
+        </Center>
+      ) : items.length === 0 ? (
         <Card withBorder padding="xl">
           <Stack align="center" gap="xs">
             <IconBellOff size={32} stroke={1.4} color="var(--mantine-color-gray-5)" />
-            <Text c="dimmed">No notifications yet.</Text>
+            <Text c="dimmed">{EMPTY_COPY[tab]}</Text>
             <Text size="sm" c="dimmed">
               You will be notified as your applications progress.
             </Text>

apps/portal/src/app/layouts/PortalLayout.tsx

@@ -16,14 +16,18 @@ import {
   IconUserCircle,
 } from "@tabler/icons-react";
 import { Outlet, useLocation, useNavigate } from "react-router-dom";
+import { useMemo } from "react";
 import { useTranslation } from "react-i18next";
 import { useDispatch } from "react-redux";
 import { notify, AppHeader, AppSidebar } from "@ema-platform/ui";
 import type { NavItem } from "@ema-platform/ui";
 import { BrandMark, logout } from "@ema-platform/auth";
+import { useGetUnseenNotificationsQuery } from "@ema-platform/api";
 import { SUPPORTED_LANGUAGES } from "../i18n/config";
 import { useAppSelector } from "../store/hooks";
 
+const BADGE_POLL_MS = 60_000;
+
 type PortalNavItem = NavItem & { i18nKey: string };
 
 /**
@@ -170,6 +174,24 @@ export function PortalLayout() {
   const user = useAppSelector((state) => state.auth.user);
   const [navOpened, { toggle: toggleNav, close: closeNav }] = useDisclosure();
   const [sidebarCollapsed, { toggle: toggleSidebar }] = useDisclosure(false);
+  const { data: unseen } = useGetUnseenNotificationsQuery(undefined, {
+    pollingInterval: BADGE_POLL_MS,
+    refetchOnMountOrArgChange: false,
+  });
+
+  const sections = useMemo(
+    () =>
+      NAV_SECTIONS.map((section) => ({
+        label: section.label,
+        items: section.items.map(({ i18nKey, ...rest }) => ({
+          ...rest,
+          label: t(i18nKey),
+          badge:
+            rest.to === "/notifications" && unseen?.count ? unseen.count : undefined,
+        })),
+      })),
+    [t, unseen?.count],
+  );
 
   // Breadcrumb trail
   const segments = location.pathname.split("/").filter(Boolean);
@@ -246,13 +268,7 @@ export function PortalLayout() {
         }}
       >
         <AppSidebar
-          navItems={NAV_SECTIONS.map((section) => ({
-            label: section.label,
-            items: section.items.map(({ i18nKey, ...rest }) => ({
-              ...rest,
-              label: t(i18nKey),
-            })),
-          }))}
+          navItems={sections}
           collapsed={sidebarCollapsed}
           activePath={location.pathname}
           onToggleCollapse={toggleSidebar}