remove empty collections

src/pages/gallery/index.tsx

@@ -20,6 +20,7 @@ import {
     getFavItemIds,
     getLocalCollections,
     getCollectionUpdationTime,
+    getNonEmptyCollections,
 } from 'services/collectionService';
 import constants from 'utils/strings/constants';
 import AlertBanner from './components/AlertBanner';
@@ -160,12 +161,13 @@ export default function Gallery(props) {
         const encryptionKey = await getActualKey();
         const collections = await syncCollections(token, encryptionKey);
         const { data, isUpdated } = await syncData(token, collections);
+        const nonEmptyCollections = getNonEmptyCollections(collections, data);
         const collectionAndItsLatestFile = await getCollectionAndItsLatestFile(
             collections,
             data
         );
         const favItemIds = await getFavItemIds(data);
-        setCollections(collections);
+        setCollections(nonEmptyCollections);
         if (isUpdated) {
             setData(data);
         }

src/services/collectionService.ts

@@ -362,3 +362,16 @@ const setLocalFavoriteCollection = async (collections: collection[]) => {
         await localForage.setItem(FAV_COLLECTION, favCollection[0]);
     }
 };
+
+export const getNonEmptyCollections = (
+    collections: collection[],
+    files: file[]
+) => {
+    const nonEmptyCollectionsIds = new Set<number>();
+    for (let file of files) {
+        nonEmptyCollectionsIds.add(file.collectionID);
+    }
+    return collections.filter((collection) =>
+        nonEmptyCollectionsIds.has(collection.id)
+    );
+};