adding icon cache

components/utils/iconService.ts

@@ -1,3 +1,42 @@
+import {
+  checkChromeStorageLocalAvailable,
+  getCachedIconFromChromeStorageLocal,
+  removeCachedIconFromChromeStorageLocal,
+  saveCachedIconToChromeStorageLocal,
+} from './StorageLocalManager';
+
+const MAX_CACHED_ICON_BYTES = 256 * 1024;
+const resolvedIconCache = new Map<string, string>();
+const iconCacheLookups = new Map<string, Promise<string | null>>();
+const iconCacheRequests = new Map<string, Promise<string | null>>();
+
+const isDataUrl = (value: string): boolean => value.startsWith('data:');
+
+const isCacheableIconUrl = (value: string): boolean => {
+  try {
+    const url = new URL(value);
+    return url.protocol === 'http:' || url.protocol === 'https:';
+  } catch {
+    return false;
+  }
+};
+
+const isValidCachedIcon = (value: string | null): value is string =>
+  typeof value === 'string' && isDataUrl(value);
+
+const blobToDataUrl = (blob: Blob): Promise<string> =>
+  new Promise<string>((resolve, reject) => {
+    const reader = new FileReader();
+    reader.onloadend = () => {
+      if (typeof reader.result === 'string') {
+        resolve(reader.result);
+      } else {
+        reject(new Error('Could not convert icon to a data URL'));
+      }
+    };
+    reader.onerror = () => reject(reader.error || new Error('Could not read icon data'));
+    reader.readAsDataURL(blob);
+  });
 
 async function getWebsiteIcon(url: string): Promise<string> {
   try {
@@ -28,4 +67,83 @@ async function getWebsiteIcon(url: string): Promise<string> {
   return `https://www.google.com/s2/favicons?domain=${new URL(url).hostname}&sz=128`;
 }
 
-export { getWebsiteIcon };
+async function getCachedWebsiteIcon(iconUrl: string): Promise<string | null> {
+  if (isDataUrl(iconUrl)) return iconUrl;
+
+  const inMemoryIcon = resolvedIconCache.get(iconUrl);
+  if (inMemoryIcon) return inMemoryIcon;
+  if (!isCacheableIconUrl(iconUrl) || !checkChromeStorageLocalAvailable()) return null;
+
+  const existingLookup = iconCacheLookups.get(iconUrl);
+  if (existingLookup) return existingLookup;
+
+  const lookup = getCachedIconFromChromeStorageLocal(iconUrl)
+    .then((cachedIcon) => {
+      if (isValidCachedIcon(cachedIcon)) {
+        resolvedIconCache.set(iconUrl, cachedIcon);
+        return cachedIcon;
+      }
+      return null;
+    })
+    .catch(() => null)
+    .finally(() => {
+      iconCacheLookups.delete(iconUrl);
+    });
+
+  iconCacheLookups.set(iconUrl, lookup);
+  return lookup;
+}
+
+async function cacheWebsiteIcon(iconUrl: string): Promise<string | null> {
+  if (!isCacheableIconUrl(iconUrl) || !checkChromeStorageLocalAvailable()) return null;
+
+  const inMemoryIcon = resolvedIconCache.get(iconUrl);
+  if (inMemoryIcon) return inMemoryIcon;
+
+  const existingRequest = iconCacheRequests.get(iconUrl);
+  if (existingRequest) return existingRequest;
+
+  const request = (async () => {
+    const cachedIcon = await getCachedWebsiteIcon(iconUrl);
+    if (cachedIcon) return cachedIcon;
+
+    try {
+      const response = await fetch(iconUrl, { mode: 'cors' });
+      if (!response.ok || response.type === 'opaque') return null;
+
+      const blob = await response.blob();
+      const contentType = (blob.type || response.headers.get('content-type') || '')
+        .split(';', 1)[0]
+        .trim()
+        .toLowerCase();
+      if (!contentType.startsWith('image/') || blob.size === 0 || blob.size > MAX_CACHED_ICON_BYTES) {
+        return null;
+      }
+
+      const dataUrl = await blobToDataUrl(blob);
+      resolvedIconCache.set(iconUrl, dataUrl);
+      await saveCachedIconToChromeStorageLocal(iconUrl, dataUrl);
+      return dataUrl;
+    } catch {
+      return null;
+    }
+  })().finally(() => {
+    iconCacheRequests.delete(iconUrl);
+  });
+
+  iconCacheRequests.set(iconUrl, request);
+  return request;
+}
+
+async function removeCachedWebsiteIcon(iconUrl: string): Promise<void> {
+  resolvedIconCache.delete(iconUrl);
+  iconCacheLookups.delete(iconUrl);
+  await removeCachedIconFromChromeStorageLocal(iconUrl);
+}
+
+export {
+  cacheWebsiteIcon,
+  getCachedWebsiteIcon,
+  getWebsiteIcon,
+  removeCachedWebsiteIcon,
+};