Add follow updates feature. Close #189

assets/translation.json

@@ -338,7 +338,22 @@
     "Descending": "降序",
     "Last Reading: Chapter @ep Page @page": "上次阅读: 第 @ep 章 第 @page 页",
     "Last Reading: Page @page": "上次阅读: 第 @page 页",
-    "Replies": "回复"
+    "Replies": "回复",
+    "Follow Updates": "追更",
+    "Not Configured": "未配置",
+    "Choose a folder to follow updates." : "选择一个文件夹以追更",
+    "Choose Folder": "选择文件夹",
+    "No folders available": "没有可用的文件夹",
+    "Updating comics...": "更新漫画中...",
+    "Automatic update checking enabled." : "已启用自动更新检查",
+    "The app will check for updates at most once a day." : "APP将每天最多检查一次更新",
+    "Change Folder": "更改文件夹",
+    "Check Now": "立即检查",
+    "Updates": "更新",
+    "No updates found": "未找到更新",
+    "All Comics": "全部漫画",
+    "The comic will be marked as no updates as soon as you read it.": "漫画将在您阅读后立即标记为无更新",
+    "Disable": "禁用"
   },
   "zh_TW": {
     "Home": "首頁",
@@ -679,6 +694,21 @@
     "Descending": "降序",
     "Last Reading: Chapter @ep Page @page": "上次閱讀: 第 @ep 章 第 @page 頁",
     "Last Reading: Page @page": "上次閱讀: 第 @page 頁",
-    "Replies": "回覆"
+    "Replies": "回覆",
+    "Follow Updates": "追更",
+    "Not Configured": "未配置",
+    "Choose a folder to follow updates." : "選擇一個文件夾以追更",
+    "Choose Folder": "選擇文件夾",
+    "No folders available": "沒有可用的文件夾",
+    "Updating comics...": "更新漫畫中...",
+    "Automatic update checking enabled." : "已啟用自動更新檢查",
+    "The app will check for updates at most once a day." : "APP將每天最多檢查一次更新",
+    "Change Folder": "更改文件夾",
+    "Check Now": "立即檢查",
+    "Updates": "更新",
+    "No updates found": "未找到更新",
+    "All Comics": "全部漫畫",
+    "The comic will be marked as no updates as soon as you read it.": "漫畫將在您閱讀後立即標記為無更新",
+    "Disable": "禁用"
   }
 }

lib/foundation/appdata.dart

@@ -159,6 +159,7 @@ class _Settings with ChangeNotifier {
     'autoAddLanguageFilter': 'none', // none, chinese, english, japanese
     'comicSourceListUrl': "https://cdn.jsdelivr.net/gh/venera-app/venera-configs@latest/index.json",
     'preloadImageCount': 4,
+    'followUpdatesFolder': null,
   };
 
   operator [](String key) {

lib/foundation/comic_source/models.dart

@@ -295,6 +295,41 @@ class ComicDetails with HistoryMixin {
     }
     return null;
   }
+
+  String? _validateUpdateTime(String time) {
+    time = time.split(" ").first;
+    var segments = time.split("-");
+    if (segments.length != 3) return null;
+    var year = int.tryParse(segments[0]);
+    var month = int.tryParse(segments[1]);
+    var day = int.tryParse(segments[2]);
+    if (year == null || month == null || day == null) return null;
+    if (year < 2000 || year > 3000) return null;
+    if (month < 1 || month > 12) return null;
+    if (day < 1 || day > 31) return null;
+    return "$year-$month-$day";
+  }
+
+  String? findUpdateTime() {
+    if (updateTime != null) {
+      return _validateUpdateTime(updateTime!);
+    }
+    const acceptedNamespaces = [
+      "更新",
+      "最後更新",
+      "最后更新",
+      "update",
+      "last update",
+    ];
+    for (var entry in tags.entries) {
+      if (acceptedNamespaces.contains(entry.key.toLowerCase()) &&
+          entry.value.isNotEmpty) {
+        var value = entry.value.first;
+        return _validateUpdateTime(value);
+      }
+    }
+    return null;
+  }
 }
 
 class ArchiveInfo {

lib/foundation/favorites.dart

@@ -6,6 +6,7 @@ import 'package:venera/foundation/appdata.dart';
 import 'package:venera/foundation/image_provider/local_favorite_image.dart';
 import 'package:venera/foundation/local.dart';
 import 'package:venera/foundation/log.dart';
+import 'package:venera/pages/follow_updates_page.dart';
 import 'package:venera/utils/tags_translation.dart';
 import 'dart:io';
 
@@ -154,6 +155,38 @@ class FavoriteItemWithFolderInfo extends FavoriteItem {
         );
 }
 
+class FavoriteItemWithUpdateInfo extends FavoriteItem {
+  String? updateTime;
+
+  DateTime? lastCheckTime;
+
+  bool hasNewUpdate;
+
+  FavoriteItemWithUpdateInfo(
+    FavoriteItem item,
+    this.updateTime,
+    this.hasNewUpdate,
+    int? lastCheckTime,
+  )   : lastCheckTime = lastCheckTime == null
+            ? null
+            : DateTime.fromMillisecondsSinceEpoch(lastCheckTime),
+        super(
+          id: item.id,
+          name: item.name,
+          coverPath: item.coverPath,
+          author: item.author,
+          type: item.type,
+          tags: item.tags,
+        );
+
+  @override
+  String get description {
+    var updateTime = this.updateTime ?? "Unknown";
+    var sourceName = type.comicSource?.name ?? "Unknown";
+    return "$updateTime | $sourceName";
+  }
+}
+
 class LocalFavoritesManager with ChangeNotifier {
   factory LocalFavoritesManager() =>
       cache ?? (cache = LocalFavoritesManager._create());
@@ -599,6 +632,7 @@ class LocalFavoritesManager with ChangeNotifier {
       return;
     }
     _modifiedAfterLastCache = true;
+    var followUpdatesFolder = appdata.settings['followUpdatesFolder'];
     for (final folder in folderNames) {
       var rows = _db.select("""
         select * from "$folder"
@@ -627,9 +661,13 @@ class LocalFavoritesManager with ChangeNotifier {
             UPDATE "$folder"
             SET 
               $updateLocationSql
+              ${followUpdatesFolder == folder ? "has_new_update = 0," : ""}
               time = ?
-            WHERE id == ?;
+            WHERE id == ? and type == ?;
-          """, [newTime, id]);
+          """, [newTime, id, type.value]);
+        if (followUpdatesFolder == folder) {
+          updateFollowUpdatesUI();
+        }
       }
     }
     notifyListeners();
@@ -783,6 +821,114 @@ class LocalFavoritesManager with ChangeNotifier {
     }
   }
 
+  void prepareTableForFollowUpdates(String table) {
+    // check if the table has the column "last_update_time" "has_new_update" "last_check_time"
+    var columns = _db.select("""
+      pragma table_info("$table");
+    """);
+    if (!columns.any((element) => element["name"] == "last_update_time")) {
+      _db.execute("""
+        alter table "$table"
+        add column last_update_time TEXT;
+      """);
+    }
+    if (!columns.any((element) => element["name"] == "has_new_update")) {
+      _db.execute("""
+        alter table "$table"
+        add column has_new_update int;
+      """);
+    }
+    _db.execute("""
+        update "$table"
+        set has_new_update = 0;
+      """);
+    if (!columns.any((element) => element["name"] == "last_check_time")) {
+      _db.execute("""
+        alter table "$table"
+        add column last_check_time int;
+      """);
+    }
+  }
+
+  void updateUpdateTime(
+    String folder,
+    String id,
+    ComicType type,
+    String updateTime,
+  ) {
+    var oldTime = _db.select("""
+      select last_update_time from "$folder"
+      where id == ? and type == ?;
+    """, [id, type.value]).first['last_update_time'];
+    var hasNewUpdate = oldTime != updateTime;
+    _db.execute("""
+      update "$folder"
+      set last_update_time = ?, has_new_update = ?, last_check_time = ?
+      where id == ? and type == ?;
+    """, [
+      updateTime,
+      hasNewUpdate ? 1 : 0,
+      DateTime.now().millisecondsSinceEpoch,
+      id,
+      type.value,
+    ]);
+  }
+
+  int countUpdates(String folder) {
+    return _db.select("""
+      select count(*) as c from "$folder"
+      where has_new_update == 1;
+    """).first['c'];
+  }
+
+  List<FavoriteItemWithUpdateInfo> getUpdates(String folder) {
+    if (!existsFolder(folder)) {
+      return [];
+    }
+    var res = _db.select("""
+      select * from "$folder"
+      where has_new_update == 1;
+    """);
+    return res
+        .map(
+          (e) => FavoriteItemWithUpdateInfo(
+            FavoriteItem.fromRow(e),
+            e['last_update_time'],
+            e['has_new_update'] == 1,
+            e['last_check_time'],
+          ),
+        )
+        .toList();
+  }
+
+  List<FavoriteItemWithUpdateInfo> getComicsWithUpdatesInfo(String folder) {
+    if (!existsFolder(folder)) {
+      return [];
+    }
+    var res = _db.select("""
+      select * from "$folder";
+    """);
+    return res
+        .map(
+          (e) => FavoriteItemWithUpdateInfo(
+            FavoriteItem.fromRow(e),
+            e['last_update_time'],
+            e['has_new_update'] == 1,
+            e['last_check_time'],
+          ),
+        )
+        .toList();
+  }
+
+  void markAsRead(String folder, String id, ComicType type) {
+    var folder = appdata.settings['followUpdatesFolder'];
+    _db.execute("""
+      update "$folder"
+      set has_new_update = 0
+      where id == ? and type == ?;
+    """, [id, type.value]);
+  }
+
   void close() {
     _db.dispose();
   }

lib/init.dart

@@ -10,6 +10,9 @@ import 'package:venera/foundation/js_engine.dart';
 import 'package:venera/foundation/local.dart';
 import 'package:venera/foundation/log.dart';
 import 'package:venera/network/cookie_jar.dart';
+import 'package:venera/pages/comic_source_page.dart';
+import 'package:venera/pages/follow_updates_page.dart';
+import 'package:venera/pages/settings/settings_page.dart';
 import 'package:venera/utils/app_links.dart';
 import 'package:venera/utils/tags_translation.dart';
 import 'package:venera/utils/translations.dart';
@@ -55,3 +58,23 @@ Future<void> init() async {
     Log.error("Unhandled Exception", "${details.exception}\n${details.stack}");
   };
 }
+
+Future<void> _checkAppUpdates() async {
+  var lastCheck = appdata.implicitData['lastCheckUpdate'] ?? 0;
+  var now = DateTime.now().millisecondsSinceEpoch;
+  if (now - lastCheck < 24 * 60 * 60 * 1000) {
+    return;
+  }
+  appdata.implicitData['lastCheckUpdate'] = now;
+  appdata.writeImplicitData();
+  ComicSourcePage.checkComicSourceUpdate();
+  if (appdata.settings['checkUpdateOnStart']) {
+    await Future.delayed(const Duration(milliseconds: 300));
+    await checkUpdateUi(false);
+  }
+}
+
+void checkUpdates() {
+  _checkAppUpdates();
+  FollowUpdatesService.initChecker();
+}

lib/main.dart

@@ -62,6 +62,7 @@ class _MyAppState extends State<MyApp> with WidgetsBindingObserver {
     App.registerForceRebuild(forceRebuild);
     SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
     WidgetsBinding.instance.addObserver(this);
+    checkUpdates();
     super.initState();
   }
 

lib/pages/follow_updates_page.dart

@@ -0,0 +1,665 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:venera/components/components.dart';
+import 'package:venera/foundation/app.dart';
+import 'package:venera/foundation/appdata.dart';
+import 'package:venera/foundation/favorites.dart';
+import 'package:venera/foundation/log.dart';
+import 'package:venera/utils/translations.dart';
+import '../foundation/global_state.dart';
+
+class FollowUpdatesWidget extends StatefulWidget {
+  const FollowUpdatesWidget({super.key});
+
+  @override
+  State<FollowUpdatesWidget> createState() => _FollowUpdatesWidgetState();
+}
+
+class _FollowUpdatesWidgetState
+    extends AutomaticGlobalState<FollowUpdatesWidget> {
+  int _count = 0;
+
+  String? get folder => appdata.settings["followUpdatesFolder"];
+
+  void getCount() {
+    if (folder == null) {
+      _count = 0;
+      return;
+    }
+    if (!LocalFavoritesManager().folderNames.contains(folder)) {
+      _count = 0;
+      appdata.settings["followUpdatesFolder"] = null;
+      Future.microtask(() {
+        appdata.saveData();
+      });
+    } else {
+      _count = LocalFavoritesManager().countUpdates(folder!);
+    }
+  }
+
+  void updateCount() {
+    setState(() {
+      getCount();
+    });
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    getCount();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return SliverToBoxAdapter(
+      child: Container(
+        margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 8),
+        decoration: BoxDecoration(
+          border: Border.all(
+            color: Theme.of(context).colorScheme.outlineVariant,
+            width: 0.6,
+          ),
+          borderRadius: BorderRadius.circular(8),
+        ),
+        child: InkWell(
+          borderRadius: BorderRadius.circular(8),
+          onTap: () {
+            context.to(() => FollowUpdatesPage());
+          },
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              SizedBox(
+                height: 56,
+                child: Row(
+                  children: [
+                    Center(
+                      child: Text('Follow Updates'.tl, style: ts.s18),
+                    ),
+                    const Spacer(),
+                    const Icon(Icons.arrow_right),
+                  ],
+                ),
+              ).paddingHorizontal(16),
+              if (_count > 0)
+                Container(
+                  padding:
+                      const EdgeInsets.symmetric(horizontal: 16, vertical: 2),
+                  margin: const EdgeInsets.only(bottom: 16, left: 16),
+                  decoration: BoxDecoration(
+                    borderRadius: BorderRadius.circular(8),
+                    color: Theme.of(context).colorScheme.primaryContainer,
+                  ),
+                  child: Text(
+                    '@c updates'.tlParams({
+                      'c': _count,
+                    }),
+                    style: ts.s16,
+                  ),
+                ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  @override
+  Object? get key => 'FollowUpdatesWidget';
+}
+
+class FollowUpdatesPage extends StatefulWidget {
+  const FollowUpdatesPage({super.key});
+
+  @override
+  State<FollowUpdatesPage> createState() => _FollowUpdatesPageState();
+}
+
+class _FollowUpdatesPageState extends AutomaticGlobalState<FollowUpdatesPage> {
+  String? get folder => appdata.settings["followUpdatesFolder"];
+
+  var updatedComics = <FavoriteItemWithUpdateInfo>[];
+  var allComics = <FavoriteItemWithUpdateInfo>[];
+
+  /// Sort comics by update time in descending order with nulls at the end.
+  void sortComics() {
+    allComics.sort((a, b) {
+      if (a.updateTime == null && b.updateTime == null) {
+        return 0;
+      } else if (a.updateTime == null) {
+        return -1;
+      } else if (b.updateTime == null) {
+        return 1;
+      }
+      return b.updateTime!.compareTo(a.updateTime!);
+    });
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    if (folder != null) {
+      allComics = LocalFavoritesManager().getComicsWithUpdatesInfo(folder!);
+      sortComics();
+      updatedComics = allComics.where((c) => c.hasNewUpdate).toList();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: SmoothCustomScrollView(
+        slivers: [
+          SliverAppbar(title: Text('Follow Updates'.tl)),
+          if (folder == null)
+            buildNotConfigured(context)
+          else
+            buildConfigured(context),
+          SliverPadding(padding: const EdgeInsets.only(top: 8)),
+          buildUpdatedComics(),
+          buildAllComics(),
+        ],
+      ),
+    );
+  }
+
+  Widget buildNotConfigured(BuildContext context) {
+    return SliverToBoxAdapter(
+      child: Container(
+        margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 8),
+        decoration: BoxDecoration(
+          border: Border.all(
+            color: Theme.of(context).colorScheme.outlineVariant,
+            width: 0.6,
+          ),
+          borderRadius: BorderRadius.circular(8),
+        ),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            ListTile(
+              leading: Icon(Icons.info_outline),
+              title: Text("Not Configured".tl),
+            ),
+            Text(
+              "Choose a folder to follow updates.".tl,
+              style: ts.s16,
+            ).paddingHorizontal(16),
+            const SizedBox(height: 8),
+            FilledButton.tonal(
+              onPressed: showSelector,
+              child: Text("Choose Folder".tl),
+            ).paddingHorizontal(16).toAlign(Alignment.centerRight),
+            const SizedBox(height: 16),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget buildConfigured(BuildContext context) {
+    return SliverToBoxAdapter(
+      child: Container(
+        margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 8),
+        decoration: BoxDecoration(
+          border: Border.all(
+            color: Theme.of(context).colorScheme.outlineVariant,
+            width: 0.6,
+          ),
+          borderRadius: BorderRadius.circular(8),
+        ),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            ListTile(
+              leading: Icon(Icons.stars_outlined),
+              title: Text(folder!),
+            ),
+            Text(
+              "Automatic update checking enabled.".tl,
+              style: ts.s14,
+            ).paddingHorizontal(16),
+            Text(
+              "The app will check for updates at most once a day.".tl,
+              style: ts.s14,
+            ).paddingHorizontal(16),
+            const SizedBox(height: 8),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.end,
+              children: [
+                TextButton(
+                  onPressed: showSelector,
+                  child: Text("Change Folder".tl),
+                ),
+                FilledButton.tonal(
+                  onPressed: checkNow,
+                  child: Text("Check Now".tl),
+                ),
+                const SizedBox(width: 16),
+              ],
+            ),
+            const SizedBox(height: 16),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget buildUpdatedComics() {
+    return SliverMainAxisGroup(
+      slivers: [
+        SliverToBoxAdapter(
+          child: Container(
+            margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+            padding: const EdgeInsets.symmetric(vertical: 4),
+            decoration: BoxDecoration(
+              border: Border(
+                bottom: BorderSide(
+                  color: Theme.of(context).colorScheme.outlineVariant,
+                  width: 0.6,
+                ),
+              ),
+            ),
+            child: Row(
+              children: [
+                Icon(Icons.update),
+                const SizedBox(width: 8),
+                Text(
+                  "Updates".tl,
+                  style: ts.s18,
+                ),
+              ],
+            ),
+          ),
+        ),
+        if (updatedComics.isNotEmpty)
+          SliverToBoxAdapter(
+            child: Text(
+                    "The comic will be marked as no updates as soon as you read it."
+                        .tl)
+                .paddingHorizontal(16)
+                .paddingVertical(4),
+          ),
+        if (updatedComics.isNotEmpty)
+          SliverGridComics(comics: updatedComics)
+        else
+          SliverToBoxAdapter(
+            child: Row(
+              children: [
+                Container(
+                  margin:
+                      const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+                  padding:
+                      const EdgeInsets.symmetric(horizontal: 12, vertical: 4),
+                  decoration: BoxDecoration(
+                    color: Theme.of(context).colorScheme.surfaceContainerLow,
+                    borderRadius: BorderRadius.circular(16),
+                  ),
+                  child: Row(
+                    mainAxisSize: MainAxisSize.min,
+                    children: [
+                      Text(
+                        "No updates found".tl,
+                        style: ts.s16,
+                      ),
+                    ],
+                  ),
+                )
+              ],
+            ),
+          ),
+      ],
+    );
+  }
+
+  Widget buildAllComics() {
+    return SliverMainAxisGroup(
+      slivers: [
+        SliverToBoxAdapter(
+          child: Container(
+            margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+            padding: const EdgeInsets.symmetric(vertical: 4),
+            decoration: BoxDecoration(
+              border: Border(
+                bottom: BorderSide(
+                  color: Theme.of(context).colorScheme.outlineVariant,
+                  width: 0.6,
+                ),
+              ),
+            ),
+            child: Row(
+              children: [
+                Icon(Icons.list),
+                const SizedBox(width: 8),
+                Text(
+                  "All Comics".tl,
+                  style: ts.s18,
+                ),
+              ],
+            ),
+          ),
+        ),
+        SliverGridComics(comics: allComics),
+      ],
+    );
+  }
+
+  void showSelector() {
+    var folders = LocalFavoritesManager().folderNames;
+    if (folders.isEmpty) {
+      context.showMessage(message: "No folders available".tl);
+      return;
+    }
+    String? selectedFolder;
+    showDialog(
+      context: App.rootContext,
+      builder: (context) {
+        return StatefulBuilder(builder: (context, setState) {
+          return ContentDialog(
+            title: "Choose Folder".tl,
+            content: Column(
+              children: [
+                ListTile(
+                  title: Text("Folder".tl),
+                  trailing: Select(
+                    minWidth: 120,
+                    current: selectedFolder,
+                    values: folders,
+                    onTap: (i) {
+                      setState(() {
+                        selectedFolder = folders[i];
+                      });
+                    },
+                  ),
+                ),
+              ],
+            ),
+            actions: [
+              if (appdata.settings["followUpdatesFolder"] != null)
+                TextButton(
+                  onPressed: () {
+                    disable();
+                    context.pop();
+                  },
+                  child: Text("Disable".tl),
+                ),
+              FilledButton(
+                onPressed: selectedFolder == null
+                    ? null
+                    : () {
+                        context.pop();
+                        setFolder(selectedFolder!);
+                      },
+                child: Text("Confirm".tl),
+              ),
+            ],
+          );
+        });
+      },
+    );
+  }
+
+  void disable() {
+    appdata.settings["followUpdatesFolder"] = null;
+    appdata.saveData();
+    updateFollowUpdatesUI();
+  }
+
+  void setFolder(String folder) async {
+    FollowUpdatesService.cancelChecking?.call();
+    LocalFavoritesManager().prepareTableForFollowUpdates(folder);
+
+    var count = LocalFavoritesManager().count(folder);
+
+    if (count > 0) {
+      bool isCanceled = false;
+      void onCancel() {
+        isCanceled = true;
+      }
+
+      var loadingController = showLoadingDialog(
+        App.rootContext,
+        withProgress: true,
+        cancelButtonText: "Cancel".tl,
+        onCancel: onCancel,
+        message: "Updating comics...".tl,
+      );
+
+      await for (var progress in _updateFolder(folder, true)) {
+        if (isCanceled) {
+          return;
+        }
+        loadingController.setProgress(progress.current / progress.total);
+      }
+
+      loadingController.close();
+    }
+
+    setState(() {
+      appdata.settings["followUpdatesFolder"] = folder;
+      updatedComics = [];
+      allComics = LocalFavoritesManager().getComicsWithUpdatesInfo(folder);
+      sortComics();
+    });
+    appdata.saveData();
+  }
+
+  void checkNow() async {
+    FollowUpdatesService.cancelChecking?.call();
+
+    bool isCanceled = false;
+    void onCancel() {
+      isCanceled = true;
+    }
+
+    var loadingController = showLoadingDialog(
+      App.rootContext,
+      withProgress: true,
+      cancelButtonText: "Cancel".tl,
+      onCancel: onCancel,
+      message: "Updating comics...".tl,
+    );
+
+    int updated = 0;
+
+    await for (var progress in _updateFolder(folder!, true)) {
+      if (isCanceled) {
+        return;
+      }
+      loadingController.setProgress(progress.current / progress.total);
+      updated = progress.updated;
+    }
+
+    loadingController.close();
+
+    if (updated > 0) {
+      GlobalState.findOrNull<_FollowUpdatesWidgetState>()?.updateCount();
+      updateComics();
+    }
+  }
+
+  void updateComics() {
+    if (folder == null) {
+      setState(() {
+        allComics = [];
+        updatedComics = [];
+      });
+      return;
+    }
+    setState(() {
+      allComics = LocalFavoritesManager().getComicsWithUpdatesInfo(folder!);
+      sortComics();
+      updatedComics = allComics.where((c) => c.hasNewUpdate).toList();
+    });
+  }
+
+  @override
+  Object? get key => 'FollowUpdatesPage';
+}
+
+class _UpdateProgress {
+  final int total;
+  final int current;
+  final int errors;
+  final int updated;
+
+  _UpdateProgress(this.total, this.current, this.errors, this.updated);
+}
+
+void _updateFolderBase(
+  String folder,
+  StreamController<_UpdateProgress> stream,
+  bool ignoreCheckTime,
+) async {
+  var comics = LocalFavoritesManager().getComicsWithUpdatesInfo(folder);
+  int current = 0;
+  int errors = 0;
+  int updated = 0;
+  var futures = <Future>[];
+  const maxConcurrent = 5;
+
+  for (int i = 0; i < comics.length; i++) {
+    if (stream.isClosed) {
+      return;
+    }
+    if (!ignoreCheckTime) {
+      var lastCheckTime = comics[i].lastCheckTime;
+      if (lastCheckTime != null &&
+          DateTime.now().difference(lastCheckTime).inDays < 1) {
+        current++;
+        stream.add(_UpdateProgress(comics.length, current, errors, updated));
+        continue;
+      }
+    }
+
+    if (futures.length >= maxConcurrent) {
+      await Future.any(futures);
+    }
+
+    var future = () async {
+      int retries = 3;
+      while (true) {
+        try {
+          var c = comics[i];
+          var comicSource = c.type.comicSource;
+          if (comicSource == null) return;
+          var newInfo = (await comicSource.loadComicInfo!(c.id)).data;
+
+          var newTags = <String>[];
+          for (var entry in newInfo.tags.entries) {
+            const shouldIgnore = ['author', 'artist', 'time'];
+            var namespace = entry.key;
+            if (shouldIgnore.contains(namespace.toLowerCase())) {
+              continue;
+            }
+            for (var tag in entry.value) {
+              newTags.add("$namespace:$tag");
+            }
+          }
+
+          var item = FavoriteItem(
+            id: c.id,
+            name: newInfo.title,
+            coverPath: newInfo.cover,
+            author: newInfo.subTitle ??
+                newInfo.tags['author']?.firstOrNull ??
+                c.author,
+            type: c.type,
+            tags: newTags,
+          );
+
+          LocalFavoritesManager().updateInfo(folder, item);
+
+          var updateTime = newInfo.findUpdateTime();
+          if (updateTime != null && updateTime != c.updateTime) {
+            LocalFavoritesManager().updateUpdateTime(
+              folder,
+              c.id,
+              c.type,
+              updateTime,
+            );
+          }
+          updated++;
+          return;
+        } catch (e, s) {
+          Log.error("Check Updates", e, s);
+          retries--;
+          if (retries == 0) {
+            errors++;
+            return;
+          }
+        } finally {
+          current++;
+          stream.add(_UpdateProgress(comics.length, current, errors, updated));
+        }
+      }
+    }();
+
+    future.then((_) {
+      futures.remove(future);
+    });
+
+    futures.add(future);
+  }
+
+  await Future.wait(futures);
+
+  stream.close();
+}
+
+Stream<_UpdateProgress> _updateFolder(String folder, bool ignoreCheckTime) {
+  var stream = StreamController<_UpdateProgress>();
+  _updateFolderBase(folder, stream, ignoreCheckTime);
+  return stream.stream;
+}
+
+/// Background service for checking updates
+abstract class FollowUpdatesService {
+  static bool isChecking = false;
+
+  static void Function()? cancelChecking;
+
+  static void check() async {
+    if (isChecking) {
+      return;
+    }
+    var folder = appdata.settings["followUpdatesFolder"];
+    if (folder == null) {
+      return;
+    }
+    bool isCanceled = false;
+    cancelChecking = () {
+      isCanceled = true;
+    };
+
+    isChecking = true;
+    int updated = 0;
+    try {
+      await for (var progress in _updateFolder(folder, false)) {
+        if (isCanceled) {
+          return;
+        }
+        updated = progress.updated;
+      }
+    } finally {
+      cancelChecking = null;
+      isChecking = false;
+      if (updated > 0) {
+        updateFollowUpdatesUI();
+      }
+    }
+  }
+
+  static void initChecker() {
+    Timer.periodic(const Duration(hours: 1), (timer) {
+      check();
+    });
+  }
+}
+
+void updateFollowUpdatesUI() {
+  GlobalState.findOrNull<_FollowUpdatesWidgetState>()?.updateCount();
+  GlobalState.findOrNull<_FollowUpdatesPageState>()?.updateComics();
+}

lib/pages/home_page.dart

@@ -12,6 +12,7 @@ import 'package:venera/foundation/log.dart';
 import 'package:venera/pages/comic_details_page/comic_page.dart';
 import 'package:venera/pages/comic_source_page.dart';
 import 'package:venera/pages/downloading_page.dart';
+import 'package:venera/pages/follow_updates_page.dart';
 import 'package:venera/pages/history_page.dart';
 import 'package:venera/pages/image_favorites_page/image_favorites_page.dart';
 import 'package:venera/pages/search_page.dart';
@@ -34,6 +35,7 @@ class HomePage extends StatelessWidget {
         const _SyncDataWidget(),
         const _History(),
         const _Local(),
+        const FollowUpdatesWidget(),
         const _ComicSourceWidget(),
         const ImageFavorites(),
         SliverPadding(padding: EdgeInsets.only(top: context.padding.bottom)),

lib/pages/main_page.dart

@@ -1,5 +1,4 @@
 import 'package:flutter/material.dart';
-import 'package:venera/foundation/appdata.dart';
 import 'package:venera/pages/categories_page.dart';
 import 'package:venera/pages/search_page.dart';
 import 'package:venera/pages/settings/settings_page.dart';
@@ -7,7 +6,6 @@ import 'package:venera/utils/translations.dart';
 
 import '../components/components.dart';
 import '../foundation/app.dart';
-import 'comic_source_page.dart';
 import 'explore_page.dart';
 import 'favorites/favorites_page.dart';
 import 'home_page.dart';
@@ -36,24 +34,8 @@ class _MainPageState extends State<MainPage> {
     _navigatorKey!.currentContext!.pop();
   }
 
-  void checkUpdates() async {
-    var lastCheck = appdata.implicitData['lastCheckUpdate'] ?? 0;
-    var now = DateTime.now().millisecondsSinceEpoch;
-    if (now - lastCheck < 24 * 60 * 60 * 1000) {
-      return;
-    }
-    appdata.implicitData['lastCheckUpdate'] = now;
-    appdata.writeImplicitData();
-    ComicSourcePage.checkComicSourceUpdate();
-    if (appdata.settings['checkUpdateOnStart']) {
-      await Future.delayed(const Duration(milliseconds: 300));
-      await checkUpdateUi(false);
-    }
-  }
-
   @override
   void initState() {
-    checkUpdates();
     _observer = NaviObserver();
     _navigatorKey = GlobalKey();
     App.mainNavigatorKey = _navigatorKey;