Add "groupByDate" to "Chapters"

src/UtilTypes.d.ts

@@ -39,3 +39,11 @@ type TransformRecordToWithDefaultFlag<T extends Record<string, any>> = {
 type MergeObjectsArray<T extends object[]> = T extends [infer F, ...infer R]
     ? F & MergeObjectsArray<R extends object[] ? R : []>
     : {};
+
+type OmitNotMatching<T, K extends keyof T> = {
+    [P in K]: T[K];
+};
+
+type ExtractCommon<T, U> = {
+    [K in keyof T & keyof U]: T[K] extends U[K] ? T[K] : never;
+};

src/modules/chapter/services/Chapters.ts

@@ -26,6 +26,7 @@ import { ReaderOpenChapterLocationState, ReaderResumeMode } from '@/modules/read
 import { AppRoutes } from '@/modules/core/AppRoute.constants.ts';
 import { getErrorMessage } from '@/lib/HelperFunctions.ts';
 import { DOWNLOAD_TYPE_FIELDS } from '@/lib/graphql/fragments/DownloadFragments.ts';
+import { epochToDate, getDateString } from '@/util/DateHelper.ts';
 
 export type ChapterAction = 'download' | 'delete' | 'bookmark' | 'unbookmark' | 'mark_as_read' | 'mark_as_unread';
 
@@ -455,4 +456,19 @@ export class Chapters {
             updateInitialChapter,
         };
     }
+
+    /**
+     * Returns the chapters grouped by the passed key representing a timestamp.
+     *
+     * The timestamp gets mapped to a string via {@link getDateString}
+     */
+    static groupByDate<
+        T extends Pick<ChapterType, 'lastReadAt'> | Pick<ChapterType, 'fetchedAt'> | Pick<ChapterType, 'uploadDate'>,
+        K extends keyof ExtractCommon<OmitNotMatching<ChapterType, 'lastReadAt' | 'fetchedAt' | 'uploadDate'>, T>,
+    >(chapters: T[], key: K): Record<string, T[]> {
+        return Object.groupBy(chapters, (chapter) => getDateString(epochToDate(Number(chapter[key])))) as Record<
+            string,
+            T[]
+        >;
+    }
 }

src/modules/history/screens/History.tsx

@@ -12,30 +12,15 @@ import { useTranslation } from 'react-i18next';
 import { requestManager } from '@/lib/requests/RequestManager.ts';
 import { LoadingPlaceholder } from '@/modules/core/components/placeholder/LoadingPlaceholder.tsx';
 import { EmptyViewAbsoluteCentered } from '@/modules/core/components/placeholder/EmptyViewAbsoluteCentered.tsx';
-import { ChapterType } from '@/lib/graphql/generated/graphql.ts';
 import { StyledGroupedVirtuoso } from '@/modules/core/components/virtuoso/StyledGroupedVirtuoso.tsx';
 import { StyledGroupHeader } from '@/modules/core/components/virtuoso/StyledGroupHeader.tsx';
 import { StyledGroupItemWrapper } from '@/modules/core/components/virtuoso/StyledGroupItemWrapper.tsx';
-import { epochToDate, getDateString } from '@/util/DateHelper.ts';
 import { defaultPromiseErrorHandler } from '@/lib/DefaultPromiseErrorHandler.ts';
 import { VirtuosoUtil } from '@/lib/virtuoso/Virtuoso.util.tsx';
 import { getErrorMessage } from '@/lib/HelperFunctions.ts';
 import { useNavBarContext } from '@/modules/navigation-bar/contexts/NavbarContext.tsx';
 import { ChapterHistoryCard } from '@/modules/history/components/ChapterHistoryCard.tsx';
-
-const groupByDate = (histories: Pick<ChapterType, 'lastReadAt'>[]): [date: string, items: number][] => {
-    if (!histories.length) {
-        return [];
-    }
-
-    const dateToItemMap = new Map<string, number>();
-    histories.forEach((item) => {
-        const date = getDateString(epochToDate(Number(item.lastReadAt)));
-        dateToItemMap.set(date, (dateToItemMap.get(date) ?? 0) + 1);
-    });
-
-    return [...dateToItemMap.entries()];
-};
+import { Chapters } from '@/modules/chapter/services/Chapters.ts';
 
 export const History: React.FC = () => {
     const { t } = useTranslation();
@@ -54,7 +39,14 @@ export const History: React.FC = () => {
     const hasNextPage = !!chapterHistoryData?.chapters.pageInfo.hasNextPage;
     const endCursor = chapterHistoryData?.chapters.pageInfo.endCursor;
     const readEntries = chapterHistoryData?.chapters.nodes ?? [];
-    const groupedHistory = useMemo(() => groupByDate(readEntries), [readEntries]);
+    const groupedHistory = useMemo(
+        () =>
+            Object.entries(Chapters.groupByDate(readEntries, 'lastReadAt')).map(([date, chapters]) => [
+                date,
+                chapters.length,
+            ]) satisfies [date: string, itemCount: number][],
+        [readEntries],
+    );
     const groupCounts: number[] = useMemo(() => groupedHistory.map((group) => group[1]), [groupedHistory]);
 
     const computeItemKey = VirtuosoUtil.useCreateGroupedComputeItemKey(

src/modules/updates/screens/Updates.tsx

@@ -12,31 +12,17 @@ import { useTranslation } from 'react-i18next';
 import { requestManager } from '@/lib/requests/RequestManager.ts';
 import { LoadingPlaceholder } from '@/modules/core/components/placeholder/LoadingPlaceholder.tsx';
 import { EmptyViewAbsoluteCentered } from '@/modules/core/components/placeholder/EmptyViewAbsoluteCentered.tsx';
-import { ChapterType } from '@/lib/graphql/generated/graphql.ts';
 import { UpdateChecker } from '@/modules/core/components/UpdateChecker.tsx';
 import { StyledGroupedVirtuoso } from '@/modules/core/components/virtuoso/StyledGroupedVirtuoso.tsx';
 import { StyledGroupHeader } from '@/modules/core/components/virtuoso/StyledGroupHeader.tsx';
 import { StyledGroupItemWrapper } from '@/modules/core/components/virtuoso/StyledGroupItemWrapper.tsx';
-import { dateTimeFormatter, epochToDate, getDateString } from '@/util/DateHelper.ts';
+import { dateTimeFormatter } from '@/util/DateHelper.ts';
 import { defaultPromiseErrorHandler } from '@/lib/DefaultPromiseErrorHandler.ts';
 import { VirtuosoUtil } from '@/lib/virtuoso/Virtuoso.util.tsx';
 import { getErrorMessage } from '@/lib/HelperFunctions.ts';
 import { ChapterUpdateCard } from '@/modules/updates/components/ChapterUpdateCard.tsx';
 import { useNavBarContext } from '@/modules/navigation-bar/contexts/NavbarContext.tsx';
-
-const groupByDate = (updates: Pick<ChapterType, 'fetchedAt'>[]): [date: string, items: number][] => {
-    if (!updates.length) {
-        return [];
-    }
-
-    const dateToItemMap = new Map<string, number>();
-    updates.forEach((item) => {
-        const date = getDateString(epochToDate(Number(item.fetchedAt)));
-        dateToItemMap.set(date, (dateToItemMap.get(date) ?? 0) + 1);
-    });
-
-    return [...dateToItemMap.entries()];
-};
+import { Chapters } from '@/modules/chapter/services/Chapters.ts';
 
 export const Updates: React.FC = () => {
     const { t } = useTranslation();
@@ -55,7 +41,14 @@ export const Updates: React.FC = () => {
     const hasNextPage = !!chapterUpdateData?.chapters.pageInfo.hasNextPage;
     const endCursor = chapterUpdateData?.chapters.pageInfo.endCursor;
     const updateEntries = chapterUpdateData?.chapters.nodes ?? [];
-    const groupedUpdates = useMemo(() => groupByDate(updateEntries), [updateEntries]);
+    const groupedUpdates = useMemo(
+        () =>
+            Object.entries(Chapters.groupByDate(updateEntries, 'fetchedAt')).map(([date, chapters]) => [
+                date,
+                chapters.length,
+            ]) satisfies [date: string, itemCount: number][],
+        [updateEntries],
+    );
     const groupCounts: number[] = useMemo(() => groupedUpdates.map((group) => group[1]), [groupedUpdates]);
 
     const computeItemKey = VirtuosoUtil.useCreateGroupedComputeItemKey(