From bef60d0657142724a3e61551ff5165bde984d271 Mon Sep 17 00:00:00 2001
From: Shivam Mishra <scm.mymail@gmail.com>
Date: Wed, 23 Jul 2025 14:39:07 +0400
Subject: [PATCH] feat: add caching of assets using service workers

---
 public/sw.js | 132 ++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 109 insertions(+), 23 deletions(-)

diff --git a/public/sw.js b/public/sw.js
index 2ad6cafb0..c529b0e59 100644
--- a/public/sw.js
+++ b/public/sw.js
@@ -1,37 +1,123 @@
 /* eslint-disable no-restricted-globals, no-console */
 /* globals clients */
-self.addEventListener('push', event => {
-  let notification = event.data && event.data.json();
+const CACHE_NAME = 'vite-assets-cache-v1'; // Bump this to invalidate old caches
+const CACHE_TTL = 7 * 24 * 60 * 60 * 1000; // 7 days in milliseconds
+const CACHE_HEADER_NAME = 'x-woot-sw-cache-time';
 
+async function addCacheTime(response) {
+  const headers = new Headers(response.headers);
+  headers.set(CACHE_HEADER_NAME, Date.now().toString());
+  const body = await response.blob();
+  return new Response(body, {
+    status: response.status,
+    statusText: response.statusText,
+    headers,
+  });
+}
+
+function isFresh(response) {
+  const cachedTime = response.headers.get(CACHE_HEADER_NAME);
+  if (!cachedTime) return false;
+  return Date.now() - Number(cachedTime) < CACHE_TTL;
+}
+
+async function handleAssetRequest(request) {
+  const cache = await caches.open(CACHE_NAME);
+  const cached = await cache.match(request);
+
+  if (cached && isFresh(cached)) {
+    return cached;
+  }
+
+  try {
+    const response = await fetch(request);
+    if (response.ok) {
+      const responseToCache = await addCacheTime(response);
+      // We naively cache everything - the browser will purge when needed
+      cache.put(request, responseToCache.clone());
+      return responseToCache;
+    }
+    return cached || response;
+  } catch {
+    return cached || new Response('', { status: 504, statusText: 'Gateway Timeout' });
+  }
+}
+
+self.addEventListener('fetch', event => {
+  const url = new URL(event.request.url);
+
+  if (url.pathname.startsWith('/vite/assets/')) {
+    event.respondWith(handleAssetRequest(event.request));
+  }
+});
+
+// Clean up old caches on activate
+// To trigger a cleanup we can simply change the `CACHE_NAME`
+self.addEventListener('activate', event => {
   event.waitUntil(
-    self.registration.showNotification(notification.title, {
-      tag: notification.tag,
-      data: {
-        url: notification.url,
-      },
-    })
+    caches.keys().then(keys =>
+      Promise.all(
+        keys
+          .filter(key => key !== CACHE_NAME)
+          .map(key => caches.delete(key))
+      )
+    )
   );
+  self.clients.claim();
+});
+
+self.addEventListener('push', event => {
+  if (!event.data) {
+    console.warn('Service Worker: Push event received without data');
+    return;
+  }
+
+  try {
+    const notification = event.data.json();
+
+    if (!notification.title) {
+      console.warn('Service Worker: Push notification missing title');
+      return;
+    }
+
+    event.waitUntil(
+      self.registration.showNotification(notification.title, {
+        tag: notification.tag || 'default',
+        body: notification.body || '',
+        icon: notification.icon || '/favicon.ico',
+        data: {
+          url: notification.url || '/',
+        },
+      })
+    );
+  } catch (err) {
+    console.error('Service Worker: Error parsing push notification', err);
+  }
 });
 
 self.addEventListener('notificationclick', event => {
-  let notification = event.notification;
+  const notification = event.notification;
+  notification.close();
+
+  const targetUrl = notification.data?.url || '/';
 
   event.waitUntil(
-    clients.matchAll({ type: 'window' }).then(windowClients => {
-      let matchingWindowClients = windowClients.filter(
-        client => client.url === notification.data.url
-      );
+    clients.matchAll({ type: 'window', includeUncontrolled: true })
+      .then(windowClients => {
+        const matchingClient = windowClients.find(
+          client => client.url === targetUrl
+        );
 
-      if (matchingWindowClients.length) {
-        let firstWindow = matchingWindowClients[0];
-        if (firstWindow && 'focus' in firstWindow) {
-          firstWindow.focus();
-          return;
+        if (matchingClient) {
+          return matchingClient.focus();
         }
-      }
-      if (clients.openWindow) {
-        clients.openWindow(notification.data.url);
-      }
-    })
+
+        if (clients.openWindow) {
+          return clients.openWindow(targetUrl);
+        }
+      })
+      .catch(err => {
+        console.error('Service Worker: Error handling notification click', err);
+      })
   );
 });