Use first unread chapter for continue read buttons (#689)

src/components/MangaCard.tsx

@@ -94,7 +94,16 @@ export const MangaCard = (props: MangaCardProps) => {
     const { t } = useTranslation();
 
     const { manga, gridLayout, inLibraryIndicator, selected, handleSelection, mode = 'default' } = props;
-    const { id, title, downloadCount, unreadCount: unread, inLibrary, latestReadChapter, chapters } = manga;
+    const {
+        id,
+        title,
+        downloadCount,
+        unreadCount: unread,
+        inLibrary,
+        latestReadChapter,
+        firstUnreadChapter,
+        chapters,
+    } = manga;
     const thumbnailUrl = Mangas.getThumbnailUrl(manga);
     const {
         options: { showContinueReadingButton, showUnreadBadge, showDownloadBadge },
@@ -102,7 +111,7 @@ export const MangaCard = (props: MangaCardProps) => {
 
     const mangaLinkTo = getMangaLinkTo(mode, manga.id, manga.source?.id, manga.title);
 
-    const nextChapterIndexToRead = (latestReadChapter?.sourceOrder ?? 0) + 1;
+    const nextChapterIndexToRead = firstUnreadChapter?.sourceOrder ?? 1;
     const isLatestChapterRead = chapters?.totalCount === latestReadChapter?.sourceOrder;
 
     const [isMigrateDialogOpen, setIsMigrateDialogOpen] = useState(false);

src/components/chapter/ChapterList.tsx

@@ -79,7 +79,7 @@ export const ChapterList: React.FC<IProps> = ({ manga, isRefreshing }) => {
 
     const visibleChapters = useMemo(() => filterAndSortChapters(chapters, options), [chapters, options]);
 
-    const nextChapterIndexToRead = (manga.latestReadChapter?.sourceOrder ?? 0) + 1;
+    const nextChapterIndexToRead = manga.firstUnreadChapter?.sourceOrder ?? 1;
     const isLatestChapterRead = manga.chapters.totalCount === manga.latestReadChapter?.sourceOrder;
 
     const areAllChaptersRead = manga.unreadCount === 0;

src/lib/graphql/Fragments.ts

@@ -351,6 +351,9 @@ export const FULL_MANGA_FIELDS = gql`
         latestUploadedChapter {
             ...FULL_CHAPTER_FIELDS
         }
+        firstUnreadChapter {
+            ...FULL_CHAPTER_FIELDS
+        }
     }
 `;
 

src/lib/graphql/mutations/ChapterMutation.ts

@@ -113,6 +113,9 @@ export const UPDATE_CHAPTER = gql`
                     latestReadChapter {
                         id
                     }
+                    firstUnreadChapter {
+                        id
+                    }
                 }
             }
         }
@@ -156,6 +159,9 @@ export const UPDATE_CHAPTERS = gql`
                     latestReadChapter {
                         id
                     }
+                    firstUnreadChapter {
+                        id
+                    }
                 }
             }
         }