change fetch method based on network condition. (#356)

README.md

@@ -1,7 +1,7 @@
 
 # <img width="64" src="https://user-images.githubusercontent.com/7277662/167775086-0b234f28-dee4-44f6-aae4-14a28ed4bbb6.png"> Hacki for Hacker News
 
-A [Hacker News](https://news.ycombinator.com/) client made with Flutter that is just enough.
+A [Hacker News](https://news.ycombinator.com/) client built with Flutter.
 
 [![App Store](https://img.shields.io/itunes/v/1602043763?label=App%20Store)](https://apps.apple.com/us/app/hacki/id1602043763?platform=iphone)
 [![Fdroid version](https://img.shields.io/f-droid/v/com.jiaqifeng.hacki)](https://f-droid.org/en/packages/com.jiaqifeng.hacki/)
@@ -35,22 +35,20 @@ Features:
 
 
 <p align="center">
-   <img width="200" alt="01" src="assets/screenshots/01.png"> 
-   <img width="200" alt="02" src="assets/screenshots/02.png"> 
-   <img width="200" alt="03" src="assets/screenshots/03.png"> 
-   <img width="200" alt="04" src="assets/screenshots/04.png"> 
-   <img width="200" alt="05" src="assets/screenshots/05.png"> 
-   <img width="200" alt="06" src="assets/screenshots/06.png"> 
-   <img width="200" alt="07" src="assets/screenshots/07.png"> 
-   <img width="200" alt="08" src="assets/screenshots/08.png"> 
-   <img width="200" alt="09" src="assets/screenshots/09.png"> 
-   <img width="200" alt="10" src="assets/screenshots/10.png"> 
-   <img width="200" alt="11" src="assets/screenshots/11.png"> 
-   <img width="200" alt="12" src="assets/screenshots/12.png"> 
+    <img width="400" alt="01" src="assets/screenshots/light-1.png"> 
+    <img width="400" alt="06" src="assets/screenshots/dark-1.png"> 
+    <img width="400" alt="02" src="assets/screenshots/light-2.png">
+    <img width="400" alt="07" src="assets/screenshots/dark-2.png">
+    <img width="400" alt="03" src="assets/screenshots/light-3.png"> 
+    <img width="400" alt="08" src="assets/screenshots/dark-3.png">
+    <img width="400" alt="04" src="assets/screenshots/light-4.png"> 
+    <img width="400" alt="09" src="assets/screenshots/dark-4.png"> 
+    <img width="400" alt="05" src="assets/screenshots/light-5.png">
+    <img width="400" alt="10" src="assets/screenshots/dark-5.png"> 
    
-   <img width="400" alt="ipad-01" src="assets/screenshots/ipad-01.png"> 
-   <img width="400" alt="ipad-02" src="assets/screenshots/ipad-02.png"> 
-   <img width="400" alt="ipad-03" src="assets/screenshots/ipad-03.png"> 
-   <img width="400" alt="ipad-04" src="assets/screenshots/ipad-04.png"> 
+   <img width="400" alt="ipad-01" src="assets/screenshots/tablet-light-1.png"> 
+   <img width="400" alt="ipad-02" src="assets/screenshots/tablet-dark-1.png"> 
+   <img width="400" alt="ipad-03" src="assets/screenshots/tablet-light-2.png"> 
+   <img width="400" alt="ipad-04" src="assets/screenshots/tablet-dark-2.png"> 
 </p>
 

android/app/build.gradle

@@ -50,7 +50,7 @@ android {
 
     defaultConfig {
         applicationId "com.jiaqifeng.hacki"
-        minSdkVersion 26
+        minSdkVersion 25
         targetSdkVersion 33
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName

android/app/src/main/AndroidManifest.xml

@@ -13,6 +13,9 @@
             <action android:name="android.intent.action.SEND" />
             <data android:mimeType="*/*" />
         </intent>
+        <intent>
+            <action android:name="android.support.customtabs.action.CustomTabsService" />
+        </intent>
     </queries>
 
    <application
@@ -20,7 +23,8 @@
         android:icon="@mipmap/ic_launcher"
         android:allowBackup="true"
         android:fullBackupContent="@xml/backup_rules"
-        android:usesCleartextTraffic="true">
+        android:usesCleartextTraffic="true"
+        android:enableOnBackInvokedCallback="true">
         <activity
             android:name=".MainActivity"
             android:launchMode="singleTop"

components/synced_shared_preferences/ios/Classes/SwiftSyncedSharedPreferencesPlugin.swift

@@ -76,6 +76,15 @@ final class SharedPrefsCore {
 
         return true
     }
+
+    fileprivate func remove(key: String?) -> Bool{
+        if let key = key {
+            let keyStore = NSUbiquitousKeyValueStore()
+            keyStore.removeObject(forKey: key)
+        }
+
+        return true
+    }
 }
 
 public class SwiftSyncedSharedPreferencesPlugin: NSObject, FlutterPlugin {
@@ -87,6 +96,14 @@ public class SwiftSyncedSharedPreferencesPlugin: NSObject, FlutterPlugin {
 
     public func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
         switch call.method {
+        case "remove":
+            if let params  = call.arguments as? [String: Any] {
+                let key = params[keyKey] as? String
+
+                let res = SharedPrefsCore.shared.remove(key: key)
+                result(res)
+            }
+
         case "setBool":
             if let params  = call.arguments as? [String: Any] {
                 let val = params[valKey] as? Bool

components/synced_shared_preferences/lib/synced_shared_preferences.dart

@@ -15,6 +15,14 @@ class SyncedSharedPreferences {
     const MethodChannel(channel),
   );
 
+  Future<bool?> remove({
+    required String key,
+  }) async {
+    return _channel.invokeMethod('remove', <String, dynamic>{
+      'key': key,
+    });
+  }
+
   Future<bool?> setBool({
     required String key,
     required bool val,

fastlane/metadata/android/en-US/changelogs/125.txt

@@ -0,0 +1,2 @@
+- Ability to customize text scale factor.
+- Ability to customize app's accent color.

fastlane/metadata/android/en-US/changelogs/127.txt

@@ -0,0 +1,4 @@
+- Ability to use Material 3.
+- Ability to search in thread.
+- Ability to customize text scale factor.
+- Ability to customize app's accent color.

fastlane/metadata/android/en-US/changelogs/128.txt

@@ -0,0 +1,5 @@
+- Ability to use pagination on home screen.
+- Ability to use Material 3 (experimental).
+- Ability to search in thread.
+- Ability to customize text scale factor.
+- Ability to customize app's accent color.

fastlane/metadata/android/en-US/changelogs/129.txt

@@ -0,0 +1,5 @@
+- Ability to use manual pagination on home screen.
+- Ability to use Material 3 (experimental).
+- Ability to search in thread.
+- Ability to customize text scale factor.
+- Ability to customize app's accent color.

fastlane/metadata/android/en-US/changelogs/131.txt

@@ -0,0 +1,4 @@
+- New comment indicator.
+- Ability to mark stories as read from home page.
+- Text rendering improvements.
+- Performance improvements.

fastlane/metadata/android/en-US/changelogs/132.txt

@@ -0,0 +1,4 @@
+- New comment indicator.
+- Ability to mark stories as read from home page.
+- Text rendering improvements.
+- Performance improvements.

fastlane/metadata/android/en-US/changelogs/134.txt

@@ -0,0 +1,4 @@
+- RobotoSlab as default font.
+- Material 3 design.
+- Ability to sync favorites from your Hacker News account.
+- Support for predictive back gesture.

fastlane/metadata/android/en-US/changelogs/135.txt

@@ -0,0 +1,3 @@
+- Return of true dark mode.
+- Better comment fetching strategy.
+- Minor UI fixes.

ios/Podfile.lock

@@ -137,11 +137,11 @@ EXTERNAL SOURCES:
     :path: ".symlinks/plugins/workmanager/ios"
 
 SPEC CHECKSUMS:
-  connectivity_plus: 07c49e96d7fc92bc9920617b83238c4d178b446a
-  device_info_plus: 7545d84d8d1b896cb16a4ff98c19f07ec4b298ea
+  connectivity_plus: bf0076dd84a130856aa636df1c71ccaff908fa1d
+  device_info_plus: c6fb39579d0f423935b0c9ce7ee2f44b71b9fce6
   Flutter: f04841e97a9d0b0a8025694d0796dd46242b2854
   flutter_email_sender: 02d7443217d8c41483223627972bfdc09f74276b
-  flutter_inappwebview: bfd58618f49dc62f2676de690fc6dcda1d6c3721
+  flutter_inappwebview: 3d32228f1304635e7c028b0d4252937730bbc6cf
   flutter_local_notifications: 0c0b1ae97e741e1521e4c1629a459d04b9aec743
   flutter_secure_storage: 23fc622d89d073675f2eaa109381aefbcf5a49be
   flutter_siri_suggestions: 226fb7ef33d25d3fe0d4aa2a8bcf4b72730c466f
@@ -155,15 +155,15 @@ SPEC CHECKSUMS:
   qr_code_scanner: bb67d64904c3b9658ada8c402e8b4d406d5d796e
   ReachabilitySwift: 985039c6f7b23a1da463388634119492ff86c825
   receive_sharing_intent: c0d87310754e74c0f9542947e7cbdf3a0335a3b1
-  share_plus: 599aa54e4ea31d4b4c0e9c911bcc26c55e791028
+  share_plus: c3fef564749587fc939ef86ffb283ceac0baf9f5
   shared_preferences_foundation: 5b919d13b803cadd15ed2dc053125c68730e5126
   sqflite: 31f7eba61e3074736dff8807a9b41581e4f7f15a
   synced_shared_preferences: f722742b06d65c7315b8e9f56b794c9fbd5597f7
-  url_launcher_ios: 08a3dfac5fb39e8759aeb0abbd5d9480f30fc8b4
+  url_launcher_ios: 68d46cc9766d0c41dbdc884310529557e3cd7a86
   wakelock: d0fc7c864128eac40eba1617cb5264d9c940b46f
   webview_flutter_wkwebview: 2e2d318f21a5e036e2c3f26171342e95908bd60a
   workmanager: 0afdcf5628bbde6924c21af7836fed07b42e30e6
 
 PODFILE CHECKSUM: d28e9a1c7bee335d05ddd795703aad5bf05bb937
 
-COCOAPODS: 1.11.3
+COCOAPODS: 1.13.0

ios/Runner/Info.plist

@@ -77,10 +77,8 @@
 	<key>UIApplicationSupportsIndirectInputEvents</key>
 	<true/>
 	<key>NSCameraUsageDescription</key>
-        <string>This app needs camera access to scan QR codes</string>
-        <key>io.flutter.embedded_views_preview</key>
-        <true/>
-        <key>FLTEnableWideGamut</key>
-        <false/>
+	<string>This app needs camera access to scan QR codes</string>
+	<key>io.flutter.embedded_views_preview</key>
+	<true/>
 </dict>
 </plist>

lib/blocs/auth/auth_bloc.dart

@@ -11,13 +11,13 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
   AuthBloc({
     AuthRepository? authRepository,
     PreferenceRepository? preferenceRepository,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
     SembastRepository? sembastRepository,
   })  : _authRepository = authRepository ?? locator.get<AuthRepository>(),
         _preferenceRepository =
             preferenceRepository ?? locator.get<PreferenceRepository>(),
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         _sembastRepository =
             sembastRepository ?? locator.get<SembastRepository>(),
         super(const AuthState.init()) {
@@ -31,7 +31,7 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
 
   final AuthRepository _authRepository;
   final PreferenceRepository _preferenceRepository;
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
   final SembastRepository _sembastRepository;
 
   Future<void> onInitialize(
@@ -41,7 +41,7 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
     await _authRepository.loggedIn.then((bool loggedIn) async {
       if (loggedIn) {
         final String? username = await _authRepository.username;
-        User? user = await _storiesRepository.fetchUser(id: username!);
+        User? user = await _hackerNewsRepository.fetchUser(id: username!);
 
         /// According to Hacker News' API documentation,
         /// if user has no public activity (posting a comment or story),
@@ -89,7 +89,8 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
     );
 
     if (successful) {
-      final User? user = await _storiesRepository.fetchUser(id: event.username);
+      final User? user =
+          await _hackerNewsRepository.fetchUser(id: event.username);
       emit(
         state.copyWith(
           user: user ?? User.emptyWithId(event.username),
@@ -113,6 +114,6 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
 
     await _authRepository.logout();
     await _preferenceRepository.updateUnreadCommentsIds(<int>[]);
-    await _sembastRepository.deleteAll();
+    await _sembastRepository.deleteCachedComments();
   }
 }

lib/blocs/stories/stories_bloc.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:math';
 
 import 'package:bloc/bloc.dart';
+import 'package:bloc_concurrency/bloc_concurrency.dart';
 import 'package:equatable/equatable.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/cubits/cubits.dart';
@@ -19,24 +20,32 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
     required PreferenceCubit preferenceCubit,
     required FilterCubit filterCubit,
     OfflineRepository? offlineRepository,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
     PreferenceRepository? preferenceRepository,
     Logger? logger,
   })  : _preferenceCubit = preferenceCubit,
         _filterCubit = filterCubit,
         _offlineRepository =
             offlineRepository ?? locator.get<OfflineRepository>(),
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         _preferenceRepository =
             preferenceRepository ?? locator.get<PreferenceRepository>(),
         _logger = logger ?? locator.get<Logger>(),
         super(const StoriesState.init()) {
+    on<LoadStories>(
+      onLoadStories,
+      transformer: concurrent(),
+    );
     on<StoriesInitialize>(onInitialize);
     on<StoriesRefresh>(onRefresh);
     on<StoriesLoadMore>(onLoadMore);
-    on<StoryLoaded>(onStoryLoaded);
+    on<StoryLoaded>(
+      onStoryLoaded,
+      transformer: sequential(),
+    );
     on<StoryRead>(onStoryRead);
+    on<StoryUnread>(onStoryUnread);
     on<StoriesLoaded>(onStoriesLoaded);
     on<StoriesDownload>(onDownload);
     on<StoriesCancelDownload>(onCancelDownload);
@@ -49,7 +58,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
   final PreferenceCubit _preferenceCubit;
   final FilterCubit _filterCubit;
   final OfflineRepository _offlineRepository;
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
   final PreferenceRepository _preferenceRepository;
   final Logger _logger;
   DeviceScreenType? deviceScreenType;
@@ -87,14 +96,15 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
       ),
     );
     for (final StoryType type in StoryType.values) {
-      await loadStories(type: type, emit: emit);
+      add(LoadStories(type: type));
     }
   }
 
-  Future<void> loadStories({
-    required StoryType type,
-    required Emitter<StoriesState> emit,
-  }) async {
+  Future<void> onLoadStories(
+    LoadStories event,
+    Emitter<StoriesState> emit,
+  ) async {
+    final StoryType type = event.type;
     if (state.isOfflineReading) {
       final List<int> ids =
           await _offlineRepository.getCachedStoryIds(type: type);
@@ -113,19 +123,19 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
         add(StoriesLoaded(type: type));
       });
     } else {
-      final List<int> ids = await _storiesRepository.fetchStoryIds(type: type);
+      final List<int> ids =
+          await _hackerNewsRepository.fetchStoryIds(type: type);
       emit(
         state
             .copyWithStoryIdsUpdated(type: type, to: ids)
             .copyWithCurrentPageUpdated(type: type, to: 0),
       );
-      _storiesRepository
+      await _hackerNewsRepository
           .fetchStoriesStream(ids: ids.sublist(0, state.currentPageSize))
           .listen((Story story) {
         add(StoryLoaded(story: story, type: type));
-      }).onDone(() {
-        add(StoriesLoaded(type: type));
-      });
+      }).asFuture<void>();
+      add(StoriesLoaded(type: type));
     }
   }
 
@@ -151,7 +161,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
       );
     } else {
       emit(state.copyWithRefreshed(type: event.type));
-      await loadStories(type: event.type, emit: emit);
+      add(LoadStories(type: event.type));
     }
   }
 
@@ -196,7 +206,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
           add(StoriesLoaded(type: event.type));
         });
       } else {
-        _storiesRepository
+        _hackerNewsRepository
             .fetchStoriesStream(
           ids: state.storyIdsByType[event.type]!.sublist(
             lower,
@@ -228,16 +238,18 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
     StoryLoaded event,
     Emitter<StoriesState> emit,
   ) async {
-    final bool hasRead = await _preferenceRepository.hasRead(event.story.id);
-    final bool hidden = _filterCubit.state.keywords.any(
-      (String keyword) =>
-          event.story.title.toLowerCase().contains(keyword) ||
-          event.story.text.toLowerCase().contains(keyword),
-    );
+    final Story story = event.story;
+    final bool hasRead = await _preferenceRepository.hasRead(story.id);
+    final bool hidden = _filterCubit.state.keywords.any((String keyword) {
+      // Match word only.
+      final RegExp regExp = RegExp('\\b($keyword)\\b');
+      return regExp.hasMatch(story.title.toLowerCase()) ||
+          regExp.hasMatch(story.text.toLowerCase());
+    });
     emit(
       state.copyWithStoryAdded(
         type: event.type,
-        story: event.story.copyWith(hidden: hidden),
+        story: story.copyWith(hidden: hidden),
         hasRead: hasRead,
       ),
     );
@@ -271,7 +283,8 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
       ..remove(StoryType.latest);
 
     for (final StoryType type in prioritizedTypes) {
-      final List<int> ids = await _storiesRepository.fetchStoryIds(type: type);
+      final List<int> ids =
+          await _hackerNewsRepository.fetchStoryIds(type: type);
       await _offlineRepository.cacheStoryIds(type: type, ids: ids);
       prioritizedIds.addAll(ids);
     }
@@ -291,7 +304,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
       );
 
       final Set<int> latestIds = <int>{};
-      final List<int> ids = await _storiesRepository.fetchStoryIds(
+      final List<int> ids = await _hackerNewsRepository.fetchStoryIds(
         type: StoryType.latest,
       );
       await _offlineRepository.cacheStoryIds(type: StoryType.latest, ids: ids);
@@ -345,7 +358,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
       }
 
       _logger.d('fetching story $id');
-      final Story? story = await _storiesRepository.fetchStory(id: id);
+      final Story? story = await _hackerNewsRepository.fetchStory(id: id);
 
       if (story == null) {
         if (isPrioritized) {
@@ -375,7 +388,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
       /// In other words, we are prioritizing the story itself instead of
       /// the comments in the story.
       late final StreamSubscription<Comment>? downloadStream;
-      downloadStream = _storiesRepository
+      downloadStream = _hackerNewsRepository
           .fetchAllChildrenComments(ids: story.kids)
           .whereType<Comment>()
           .listen(
@@ -458,7 +471,7 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
     StoryRead event,
     Emitter<StoriesState> emit,
   ) async {
-    unawaited(_preferenceRepository.updateHasRead(event.story.id));
+    unawaited(_preferenceRepository.addHasRead(event.story.id));
 
     emit(
       state.copyWith(
@@ -467,6 +480,19 @@ class StoriesBloc extends Bloc<StoriesEvent, StoriesState> {
     );
   }
 
+  Future<void> onStoryUnread(
+    StoryUnread event,
+    Emitter<StoriesState> emit,
+  ) async {
+    unawaited(_preferenceRepository.removeHasRead(event.story.id));
+
+    emit(
+      state.copyWith(
+        readStoriesIds: <int>{...state.readStoriesIds}..remove(event.story.id),
+      ),
+    );
+  }
+
   Future<void> onClearAllReadStories(
     ClearAllReadStories event,
     Emitter<StoriesState> emit,

lib/blocs/stories/stories_event.dart

@@ -5,6 +5,15 @@ abstract class StoriesEvent extends Equatable {
   List<Object?> get props => <Object?>[];
 }
 
+class LoadStories extends StoriesEvent {
+  LoadStories({required this.type});
+
+  final StoryType type;
+
+  @override
+  List<Object?> get props => <Object?>[type];
+}
+
 class StoriesInitialize extends StoriesEvent {
   @override
   List<Object?> get props => <Object?>[];
@@ -95,6 +104,15 @@ class StoryRead extends StoriesEvent {
   List<Object?> get props => <Object?>[story];
 }
 
+class StoryUnread extends StoriesEvent {
+  StoryUnread({required this.story});
+
+  final Story story;
+
+  @override
+  List<Object?> get props => <Object?>[story];
+}
+
 class ClearAllReadStories extends StoriesEvent {
   @override
   List<Object?> get props => <Object?>[];

lib/config/constants.dart

@@ -20,6 +20,8 @@ abstract class Constants {
       '$githubLink/issues/new?title=Found+a+bug+in+Hacki&body=Please+describe+the+problem.';
   static const String wikipediaLink = 'https://en.wikipedia.org/wiki/';
   static const String wiktionaryLink = 'https://en.wiktionary.org/wiki/';
+  static const String hackerNewsItemLinkPrefix =
+      'https://news.ycombinator.com/item?id=';
   static const String supportEmail = 'georgefung98@gmail.com';
 
   static const String _imagePath = 'assets/images';
@@ -34,15 +36,6 @@ abstract class Constants {
   static const String logFilename = 'hacki_log.txt';
   static const String previousLogFileName = 'old_hacki_log.txt';
 
-  /// Feature ids for feature discovery.
-  static const String featureAddStoryToFavList = 'add_story_to_fav_list';
-  static const String featureOpenStoryInWebView = 'open_story_in_web_view';
-  static const String featureLogIn = 'log_in';
-  static const String featurePinToTop = 'pin_to_top';
-  static const String featureJumpUpButton = 'jump_up_button_with_long_press';
-  static const String featureJumpDownButton =
-      'jump_down_button_with_long_press';
-
   static final String happyFace = <String>[
     '(๑•̀ㅂ•́)و✧',
     '( ͡• ͜ʖ ͡•)',
@@ -80,7 +73,7 @@ abstract class RegExpConstants {
   static const String number = '[0-9]+';
 }
 
-abstract class Durations {
+abstract class AppDurations {
   static const Duration ms100 = Duration(milliseconds: 100);
   static const Duration ms200 = Duration(milliseconds: 200);
   static const Duration ms300 = Duration(milliseconds: 300);

lib/config/custom_router.dart

@@ -1,12 +1,13 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:go_router/go_router.dart';
+import 'package:hacki/config/locator.dart';
 import 'package:hacki/cubits/cubits.dart';
 import 'package:hacki/screens/screens.dart';
 
 final GoRouter router = GoRouter(
   observers: <NavigatorObserver>[
-    RouteObserver<ModalRoute<dynamic>>(),
+    locator.get<RouteObserver<ModalRoute<dynamic>>>(),
   ],
   initialLocation: HomeScreen.routeName,
   routes: <RouteBase>[

lib/config/locator.dart

@@ -23,12 +23,13 @@ Future<void> setUpLocator() async {
         output: LogUtil.logOutput(logOutputFile),
       ),
     )
-    ..registerSingleton<StoriesRepository>(StoriesRepository())
+    ..registerSingleton<SembastRepository>(SembastRepository())
+    ..registerSingleton<HackerNewsRepository>(HackerNewsRepository())
+    ..registerSingleton<HackerNewsWebRepository>(HackerNewsWebRepository())
     ..registerSingleton<PreferenceRepository>(PreferenceRepository())
     ..registerSingleton<SearchRepository>(SearchRepository())
     ..registerSingleton<AuthRepository>(AuthRepository())
     ..registerSingleton<PostRepository>(PostRepository())
-    ..registerSingleton<SembastRepository>(SembastRepository())
     ..registerSingleton<OfflineRepository>(OfflineRepository())
     ..registerSingleton<DraftCache>(DraftCache())
     ..registerSingleton<CommentCache>(CommentCache())

lib/cubits/collapse/collapse_cubit.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 
 import 'package:bloc/bloc.dart';
 import 'package:equatable/equatable.dart';
+import 'package:flutter/foundation.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/services/services.dart';
 
@@ -28,11 +29,12 @@ class CollapseCubit extends Cubit<CollapseState> {
         collapsedCount: _collapseCache.totalHidden(_commentId),
         collapsed: _collapseCache.isCollapsed(_commentId),
         hidden: _collapseCache.isHidden(_commentId),
+        locked: _collapseCache.lockedId == _commentId,
       ),
     );
   }
 
-  void collapse() {
+  void collapse({required VoidCallback onStateChanged}) {
     if (state.collapsed) {
       _collapseCache.uncollapse(_commentId);
 
@@ -42,7 +44,14 @@ class CollapseCubit extends Cubit<CollapseState> {
           collapsedCount: 0,
         ),
       );
+
+      onStateChanged();
     } else {
+      if (state.locked) {
+        emit(state.copyWith(locked: false));
+        return;
+      }
+
       final Set<int> collapsedCommentIds = _collapseCache.collapse(_commentId);
 
       emit(
@@ -51,6 +60,8 @@ class CollapseCubit extends Cubit<CollapseState> {
           collapsedCount: state.collapsed ? 0 : collapsedCommentIds.length,
         ),
       );
+
+      onStateChanged();
     }
   }
 
@@ -85,6 +96,13 @@ class CollapseCubit extends Cubit<CollapseState> {
     }
   }
 
+  /// Prevent the item to be able to collapse, used when the comment
+  /// text is selected.
+  void lock() {
+    _collapseCache.lockedId = _commentId;
+    emit(state.copyWith(locked: true));
+  }
+
   @override
   Future<void> close() async {
     await _streamSubscription.cancel();

lib/cubits/collapse/collapse_state.dart

@@ -4,26 +4,39 @@ class CollapseState extends Equatable {
   const CollapseState({
     required this.collapsed,
     required this.hidden,
+    required this.locked,
     required this.collapsedCount,
   });
 
   const CollapseState.init()
       : collapsed = false,
         hidden = false,
+        locked = false,
         collapsedCount = 0;
 
   final bool collapsed;
+
+  /// The value determining whether or not the comment should show up in the
+  /// screen, this is true when the comment's parent is collapsed.
   final bool hidden;
+
+  /// The value determining whether or not the comment is collapsable.
+  /// If [locked] is true then the comment is not collapsable and vice versa.
+  final bool locked;
+
+  /// The number of children under this collapsed comment.
   final int collapsedCount;
 
   CollapseState copyWith({
     bool? collapsed,
     bool? hidden,
+    bool? locked,
     int? collapsedCount,
   }) {
     return CollapseState(
       collapsed: collapsed ?? this.collapsed,
       hidden: hidden ?? this.hidden,
+      locked: locked ?? this.locked,
       collapsedCount: collapsedCount ?? this.collapsedCount,
     );
   }
@@ -32,6 +45,7 @@ class CollapseState extends Equatable {
   List<Object?> get props => <Object?>[
         collapsed,
         hidden,
+        locked,
         collapsedCount,
       ];
 }

lib/cubits/comments/comments_cubit.dart

@@ -3,12 +3,14 @@ import 'dart:math';
 
 import 'package:bloc/bloc.dart';
 import 'package:collection/collection.dart';
+import 'package:connectivity_plus/connectivity_plus.dart';
 import 'package:equatable/equatable.dart';
 import 'package:flutter/foundation.dart';
 import 'package:hacki/config/constants.dart';
 import 'package:hacki/config/custom_router.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/cubits/cubits.dart';
+import 'package:hacki/extensions/extensions.dart';
 import 'package:hacki/models/models.dart';
 import 'package:hacki/repositories/repositories.dart';
 import 'package:hacki/screens/screens.dart';
@@ -24,6 +26,7 @@ part 'comments_state.dart';
 class CommentsCubit extends Cubit<CommentsState> {
   CommentsCubit({
     required FilterCubit filterCubit,
+    required PreferenceCubit preferenceCubit,
     required CollapseCache collapseCache,
     required bool isOfflineReading,
     required Item item,
@@ -31,18 +34,22 @@ class CommentsCubit extends Cubit<CommentsState> {
     required CommentsOrder defaultCommentsOrder,
     CommentCache? commentCache,
     OfflineRepository? offlineRepository,
-    StoriesRepository? storiesRepository,
     SembastRepository? sembastRepository,
+    HackerNewsRepository? hackerNewsRepository,
+    HackerNewsWebRepository? hackerNewsWebRepository,
     Logger? logger,
   })  : _filterCubit = filterCubit,
+        _preferenceCubit = preferenceCubit,
         _collapseCache = collapseCache,
         _commentCache = commentCache ?? locator.get<CommentCache>(),
         _offlineRepository =
             offlineRepository ?? locator.get<OfflineRepository>(),
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
         _sembastRepository =
             sembastRepository ?? locator.get<SembastRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
+        _hackerNewsWebRepository =
+            hackerNewsWebRepository ?? locator.get<HackerNewsWebRepository>(),
         _logger = logger ?? locator.get<Logger>(),
         super(
           CommentsState.init(
@@ -54,13 +61,19 @@ class CommentsCubit extends Cubit<CommentsState> {
         );
 
   final FilterCubit _filterCubit;
+  final PreferenceCubit _preferenceCubit;
   final CollapseCache _collapseCache;
   final CommentCache _commentCache;
   final OfflineRepository _offlineRepository;
-  final StoriesRepository _storiesRepository;
   final SembastRepository _sembastRepository;
+  final HackerNewsRepository _hackerNewsRepository;
+  final HackerNewsWebRepository _hackerNewsWebRepository;
   final Logger _logger;
 
+  final ItemScrollController itemScrollController = ItemScrollController();
+  final ItemPositionsListener itemPositionsListener =
+      ItemPositionsListener.create();
+
   /// The [StreamSubscription] for stream (both lazy or eager)
   /// fetching comments posted directly to the story.
   StreamSubscription<Comment>? _streamSubscription;
@@ -70,6 +83,11 @@ class CommentsCubit extends Cubit<CommentsState> {
   final Map<int, StreamSubscription<Comment>> _streamSubscriptions =
       <int, StreamSubscription<Comment>>{};
 
+  static Future<bool> get _isOnWifi async {
+    final ConnectivityResult status = await Connectivity().checkConnectivity();
+    return status == ConnectivityResult.wifi;
+  }
+
   @override
   void emit(CommentsState state) {
     if (!isClosed) {
@@ -81,6 +99,8 @@ class CommentsCubit extends Cubit<CommentsState> {
     bool onlyShowTargetComment = false,
     bool useCommentCache = false,
     List<Comment>? targetAncestors,
+    AppExceptionHandler? onError,
+    bool fetchFromWeb = true,
   }) async {
     if (onlyShowTargetComment && (targetAncestors?.isNotEmpty ?? false)) {
       emit(
@@ -91,7 +111,7 @@ class CommentsCubit extends Cubit<CommentsState> {
         ),
       );
 
-      _streamSubscription = _storiesRepository
+      _streamSubscription = _hackerNewsRepository
           .fetchAllCommentsRecursivelyStream(
             ids: targetAncestors!.last.kids,
             level: targetAncestors.last.level + 1,
@@ -108,6 +128,8 @@ class CommentsCubit extends Cubit<CommentsState> {
       state.copyWith(
         status: CommentsStatus.inProgress,
         comments: <Comment>[],
+        matchedComments: <int>[],
+        inThreadSearchQuery: '',
         currentPage: 0,
       ),
     );
@@ -115,7 +137,10 @@ class CommentsCubit extends Cubit<CommentsState> {
     final Item item = state.item;
     final Item updatedItem = state.isOfflineReading
         ? item
-        : await _storiesRepository.fetchItem(id: item.id).then(_toBuildable) ??
+        : await _hackerNewsRepository
+                .fetchItem(id: item.id)
+                .then(_toBuildable)
+                .onError((_, __) => item) ??
             item;
     final List<int> kids = _sortKids(updatedItem.kids);
 
@@ -128,15 +153,52 @@ class CommentsCubit extends Cubit<CommentsState> {
     } else {
       switch (state.fetchMode) {
         case FetchMode.lazy:
-          commentStream = _storiesRepository.fetchCommentsStream(
+          commentStream = _hackerNewsRepository.fetchCommentsStream(
             ids: kids,
             getFromCache: useCommentCache ? _commentCache.getComment : null,
           );
         case FetchMode.eager:
-          commentStream = _storiesRepository.fetchAllCommentsRecursivelyStream(
-            ids: kids,
-            getFromCache: useCommentCache ? _commentCache.getComment : null,
-          );
+          switch (state.order) {
+            case CommentsOrder.natural:
+              final bool isOnWifi = await _isOnWifi;
+              if (!isOnWifi && fetchFromWeb) {
+                commentStream = _hackerNewsWebRepository
+                    .fetchCommentsStream(state.item)
+                    .handleError((dynamic e) {
+                  _streamSubscription?.cancel();
+
+                  _logger.e(e);
+
+                  switch (e.runtimeType) {
+                    case RateLimitedWithFallbackException:
+                    case PossibleParsingException:
+                    case BrowserNotRunningException:
+                      if (_preferenceCubit.state.devModeEnabled) {
+                        onError?.call(e as AppException);
+                      }
+
+                      /// If fetching from web failed, fetch using API instead.
+                      refresh(onError: onError, fetchFromWeb: false);
+                    default:
+                      onError?.call(GenericException());
+                  }
+                });
+              } else {
+                commentStream =
+                    _hackerNewsRepository.fetchAllCommentsRecursivelyStream(
+                  ids: kids,
+                  getFromCache:
+                      useCommentCache ? _commentCache.getComment : null,
+                );
+              }
+            case CommentsOrder.oldestFirst:
+            case CommentsOrder.newestFirst:
+              commentStream =
+                  _hackerNewsRepository.fetchAllCommentsRecursivelyStream(
+                ids: kids,
+                getFromCache: useCommentCache ? _commentCache.getComment : null,
+              );
+          }
       }
     }
 
@@ -147,7 +209,10 @@ class CommentsCubit extends Cubit<CommentsState> {
       ..onDone(_onDone);
   }
 
-  Future<void> refresh() async {
+  Future<void> refresh({
+    required AppExceptionHandler? onError,
+    bool fetchFromWeb = true,
+  }) async {
     emit(
       state.copyWith(
         status: CommentsStatus.inProgress,
@@ -180,18 +245,49 @@ class CommentsCubit extends Cubit<CommentsState> {
 
     final Item item = state.item;
     final Item updatedItem =
-        await _storiesRepository.fetchItem(id: item.id) ?? item;
+        await _hackerNewsRepository.fetchItem(id: item.id) ?? item;
     final List<int> kids = _sortKids(updatedItem.kids);
 
     late final Stream<Comment> commentStream;
-    if (state.fetchMode == FetchMode.lazy) {
-      commentStream = _storiesRepository.fetchCommentsStream(
-        ids: kids,
-      );
-    } else {
-      commentStream = _storiesRepository.fetchAllCommentsRecursivelyStream(
-        ids: kids,
-      );
+
+    switch (state.fetchMode) {
+      case FetchMode.lazy:
+        commentStream = _hackerNewsRepository.fetchCommentsStream(ids: kids);
+      case FetchMode.eager:
+        switch (state.order) {
+          case CommentsOrder.natural:
+            final bool isOnWifi = await _isOnWifi;
+            if (!isOnWifi && fetchFromWeb) {
+              commentStream = _hackerNewsWebRepository
+                  .fetchCommentsStream(state.item)
+                  .handleError((dynamic e) {
+                _logger.e(e);
+
+                switch (e.runtimeType) {
+                  case RateLimitedException:
+                  case PossibleParsingException:
+                  case BrowserNotRunningException:
+                    if (_preferenceCubit.state.devModeEnabled) {
+                      onError?.call(e as AppException);
+                    }
+
+                    /// If fetching from web failed, fetch using API instead.
+                    refresh(onError: onError, fetchFromWeb: false);
+                  default:
+                    onError?.call(GenericException());
+                }
+              });
+            } else {
+              commentStream = _hackerNewsRepository
+                  .fetchAllCommentsRecursivelyStream(ids: kids);
+            }
+          case CommentsOrder.oldestFirst:
+          case CommentsOrder.newestFirst:
+            commentStream =
+                _hackerNewsRepository.fetchAllCommentsRecursivelyStream(
+              ids: kids,
+            );
+        }
     }
 
     _streamSubscription = commentStream
@@ -213,6 +309,7 @@ class CommentsCubit extends Cubit<CommentsState> {
       state.copyWith(
         onlyShowTargetComment: false,
         item: story,
+        matchedComments: <int>[],
       ),
     );
     init();
@@ -237,14 +334,17 @@ class CommentsCubit extends Cubit<CommentsState> {
         /// Ignoring because the subscription will be cancelled in close()
         // ignore: cancel_subscriptions
         final StreamSubscription<Comment> streamSubscription =
-            _storiesRepository
+            _hackerNewsRepository
                 .fetchCommentsStream(ids: comment.kids)
                 .asyncMap(_toBuildableComment)
                 .whereNotNull()
                 .listen((Comment cmt) {
           _collapseCache.addKid(cmt.id, to: cmt.parent);
           _commentCache.cacheComment(cmt);
-          _sembastRepository.cacheComment(cmt);
+
+          final Map<int, Comment> updatedIdToCommentMap =
+              Map<int, Comment>.from(state.idToCommentMap);
+          updatedIdToCommentMap[comment.id] = comment;
 
           emit(
             state.copyWith(
@@ -252,6 +352,7 @@ class CommentsCubit extends Cubit<CommentsState> {
                   state.comments.indexOf(comment) + offset + 1,
                   cmt.copyWith(level: level),
                 ),
+              idToCommentMap: updatedIdToCommentMap,
             ),
           );
           offset++;
@@ -281,7 +382,7 @@ class CommentsCubit extends Cubit<CommentsState> {
     HapticFeedbackUtil.light();
     emit(state.copyWith(fetchParentStatus: CommentsStatus.inProgress));
     final Item? parent =
-        await _storiesRepository.fetchItem(id: state.item.parent);
+        await _hackerNewsRepository.fetchItem(id: state.item.parent);
 
     if (parent == null) {
       return;
@@ -302,7 +403,7 @@ class CommentsCubit extends Cubit<CommentsState> {
   Future<void> loadRootThread() async {
     HapticFeedbackUtil.light();
     emit(state.copyWith(fetchRootStatus: CommentsStatus.inProgress));
-    final Story? parent = await _storiesRepository
+    final Story? parent = await _hackerNewsRepository
         .fetchParentStory(id: state.item.id)
         .then(_toBuildableStory);
 
@@ -322,7 +423,7 @@ class CommentsCubit extends Cubit<CommentsState> {
     }
   }
 
-  void onOrderChanged(CommentsOrder? order) {
+  void updateOrder(CommentsOrder? order) {
     if (order == null) return;
     if (state.order == order) return;
     HapticFeedbackUtil.selection();
@@ -335,7 +436,7 @@ class CommentsCubit extends Cubit<CommentsState> {
     init(useCommentCache: true);
   }
 
-  void onFetchModeChanged(FetchMode? fetchMode) {
+  void updateFetchMode(FetchMode? fetchMode) {
     if (fetchMode == null) return;
     if (state.fetchMode == fetchMode) return;
     _collapseCache.resetCollapsedComments();
@@ -349,17 +450,26 @@ class CommentsCubit extends Cubit<CommentsState> {
     init(useCommentCache: true);
   }
 
+  void scrollTo({
+    required int index,
+    double alignment = 0.0,
+  }) {
+    debugPrint('Scrolling to: $index, alignment: $alignment');
+    itemScrollController.scrollTo(
+      index: index,
+      alignment: alignment,
+      duration: AppDurations.ms400,
+    );
+  }
+
   /// Scroll to next root level comment.
-  void scrollToNextRoot(
-    ItemScrollController itemScrollController,
-    ItemPositionsListener itemPositionsListener,
-  ) {
+  void scrollToNextRoot({VoidCallback? onError}) {
     final int totalComments = state.comments.length;
     final List<Comment> onScreenComments = itemPositionsListener
         .itemPositions.value
         // The header is also a part of the list view,
         // thus ignoring it here.
-        .where((ItemPosition e) => e.index >= 1 && e.itemLeadingEdge < 0.7)
+        .where((ItemPosition e) => e.index >= 1 && e.itemLeadingEdge > 0.1)
         .sorted((ItemPosition a, ItemPosition b) => a.index.compareTo(b.index))
         .map(
           (ItemPosition e) => e.index <= state.comments.length
@@ -369,9 +479,29 @@ class CommentsCubit extends Cubit<CommentsState> {
         .whereNotNull()
         .toList();
 
-    /// The index of last comment visible on screen.
-    final int lastVisibleIndex = state.comments.indexOf(onScreenComments.last);
-    final int startIndex = min(lastVisibleIndex + 1, totalComments);
+    if (onScreenComments.isEmpty && state.comments.isNotEmpty) {
+      itemScrollController.scrollTo(
+        index: 1,
+        alignment: 0.15,
+        duration: AppDurations.ms400,
+      );
+      return;
+    }
+
+    final Comment? firstVisibleRootComment =
+        onScreenComments.firstWhereOrNull((Comment e) => e.isRoot);
+    late int startIndex;
+
+    if (firstVisibleRootComment != null) {
+      /// The index of first root level comment visible on screen.
+      final int firstVisibleRootCommentIndex =
+          state.comments.indexOf(firstVisibleRootComment);
+      startIndex = min(firstVisibleRootCommentIndex + 1, totalComments);
+    } else {
+      final int lastVisibleCommentIndex =
+          state.comments.indexOf(onScreenComments.last);
+      startIndex = min(lastVisibleCommentIndex + 1, totalComments);
+    }
 
     for (int i = startIndex; i < totalComments; i++) {
       final Comment cmt = state.comments.elementAt(i);
@@ -380,18 +510,19 @@ class CommentsCubit extends Cubit<CommentsState> {
         itemScrollController.scrollTo(
           index: i + 1,
           alignment: 0.15,
-          duration: Durations.ms400,
+          duration: AppDurations.ms400,
         );
         return;
       }
     }
+
+    if (state.status == CommentsStatus.allLoaded) {
+      onError?.call();
+    }
   }
 
   /// Scroll to previous root level comment.
-  void scrollToPreviousRoot(
-    ItemScrollController itemScrollController,
-    ItemPositionsListener itemPositionsListener,
-  ) {
+  void scrollToPreviousRoot() {
     final List<Comment> onScreenComments = itemPositionsListener
         .itemPositions.value
         // The header is also a part of the list view,
@@ -419,13 +550,57 @@ class CommentsCubit extends Cubit<CommentsState> {
         itemScrollController.scrollTo(
           index: i + 1,
           alignment: 0.15,
-          duration: Durations.ms400,
+          duration: AppDurations.ms400,
         );
         return;
       }
     }
   }
 
+  void search(String query, {String author = ''}) {
+    resetSearch();
+
+    late final bool Function(Comment cmt) conditionSatisfied;
+    final String lowercaseQuery = query.toLowerCase();
+    if (query.isEmpty && author.isEmpty) {
+      return;
+    } else if (author.isEmpty) {
+      conditionSatisfied =
+          (Comment cmt) => cmt.text.toLowerCase().contains(lowercaseQuery);
+    } else if (query.isEmpty) {
+      conditionSatisfied = (Comment cmt) => cmt.by == author;
+    } else {
+      conditionSatisfied = (Comment cmt) =>
+          cmt.text.toLowerCase().contains(lowercaseQuery) && cmt.by == author;
+    }
+
+    emit(
+      state.copyWith(
+        inThreadSearchQuery: query,
+        inThreadSearchAuthor: author,
+      ),
+    );
+
+    for (final int i in 0.to(state.comments.length, inclusive: false)) {
+      final Comment cmt = state.comments.elementAt(i);
+      if (conditionSatisfied(cmt)) {
+        emit(
+          state.copyWith(
+            matchedComments: <int>[...state.matchedComments, i],
+          ),
+        );
+      }
+    }
+  }
+
+  void resetSearch() => emit(
+        state.copyWith(
+          matchedComments: <int>[],
+          inThreadSearchQuery: '',
+          inThreadSearchAuthor: '',
+        ),
+      );
+
   List<int> _sortKids(List<int> kids) {
     switch (state.order) {
       case CommentsOrder.natural:
@@ -451,8 +626,12 @@ class CommentsCubit extends Cubit<CommentsState> {
     if (comment != null) {
       _collapseCache.addKid(comment.id, to: comment.parent);
       _commentCache.cacheComment(comment);
-      _sembastRepository.cacheComment(comment);
 
+      if (state.isOfflineReading) {
+        _sembastRepository.cacheComment(comment);
+      }
+
+      // Hide comment that matches any of the filter keywords.
       final bool hidden = _filterCubit.state.keywords.any(
         (String keyword) => comment.text.toLowerCase().contains(keyword),
       );
@@ -461,7 +640,16 @@ class CommentsCubit extends Cubit<CommentsState> {
         comment.copyWith(hidden: hidden),
       ];
 
-      emit(state.copyWith(comments: updatedComments));
+      final Map<int, Comment> updatedIdToCommentMap =
+          Map<int, Comment>.from(state.idToCommentMap);
+      updatedIdToCommentMap[comment.id] = comment;
+
+      emit(
+        state.copyWith(
+          comments: updatedComments,
+          idToCommentMap: updatedIdToCommentMap,
+        ),
+      );
     }
   }
 

lib/cubits/comments/comments_state.dart

@@ -12,6 +12,8 @@ class CommentsState extends Equatable {
   const CommentsState({
     required this.item,
     required this.comments,
+    required this.matchedComments,
+    required this.idToCommentMap,
     required this.status,
     required this.fetchParentStatus,
     required this.fetchRootStatus,
@@ -20,6 +22,8 @@ class CommentsState extends Equatable {
     required this.onlyShowTargetComment,
     required this.isOfflineReading,
     required this.currentPage,
+    required this.inThreadSearchQuery,
+    required this.inThreadSearchAuthor,
   });
 
   CommentsState.init({
@@ -28,14 +32,19 @@ class CommentsState extends Equatable {
     required this.fetchMode,
     required this.order,
   })  : comments = <Comment>[],
+        matchedComments = <int>[],
+        idToCommentMap = <int, Comment>{},
         status = CommentsStatus.idle,
         fetchParentStatus = CommentsStatus.idle,
         fetchRootStatus = CommentsStatus.idle,
         onlyShowTargetComment = false,
-        currentPage = 0;
+        currentPage = 0,
+        inThreadSearchQuery = '',
+        inThreadSearchAuthor = '';
 
   final Item item;
   final List<Comment> comments;
+  final Map<int, Comment> idToCommentMap;
   final CommentsStatus status;
   final CommentsStatus fetchParentStatus;
   final CommentsStatus fetchRootStatus;
@@ -44,10 +53,17 @@ class CommentsState extends Equatable {
   final bool onlyShowTargetComment;
   final bool isOfflineReading;
   final int currentPage;
+  final String inThreadSearchQuery;
+  final String inThreadSearchAuthor;
+
+  /// Indexes of comments that matches the query for in-thread search.
+  final List<int> matchedComments;
 
   CommentsState copyWith({
     Item? item,
     List<Comment>? comments,
+    List<int>? matchedComments,
+    Map<int, Comment>? idToCommentMap,
     CommentsStatus? status,
     CommentsStatus? fetchParentStatus,
     CommentsStatus? fetchRootStatus,
@@ -56,10 +72,13 @@ class CommentsState extends Equatable {
     bool? onlyShowTargetComment,
     bool? isOfflineReading,
     int? currentPage,
+    String? inThreadSearchQuery,
+    String? inThreadSearchAuthor,
   }) {
     return CommentsState(
       item: item ?? this.item,
       comments: comments ?? this.comments,
+      matchedComments: matchedComments ?? this.matchedComments,
       fetchParentStatus: fetchParentStatus ?? this.fetchParentStatus,
       fetchRootStatus: fetchRootStatus ?? this.fetchRootStatus,
       status: status ?? this.status,
@@ -69,11 +88,41 @@ class CommentsState extends Equatable {
           onlyShowTargetComment ?? this.onlyShowTargetComment,
       isOfflineReading: isOfflineReading ?? this.isOfflineReading,
       currentPage: currentPage ?? this.currentPage,
+      inThreadSearchQuery: inThreadSearchQuery ?? this.inThreadSearchQuery,
+      inThreadSearchAuthor: inThreadSearchAuthor ?? this.inThreadSearchAuthor,
+      idToCommentMap: idToCommentMap ?? this.idToCommentMap,
     );
   }
 
   Set<int> get commentIds => comments.map((Comment e) => e.id).toSet();
 
+  static final Map<int, bool> _isResponseCache = <int, bool>{};
+
+  bool isResponse(Comment comment) {
+    if (_isResponseCache.containsKey(comment.id)) {
+      return _isResponseCache[comment.id]!;
+    }
+
+    if (comment.isRoot) {
+      _isResponseCache[comment.id] = false;
+      return false;
+    }
+    final Comment? precedingComment = idToCommentMap[comment.parent];
+    if (precedingComment == null) {
+      _isResponseCache[comment.id] = false;
+      return false;
+    } else if (item.id == precedingComment.parent && item.by == comment.by) {
+      _isResponseCache[comment.id] = true;
+      return true;
+    } else if (idToCommentMap[precedingComment.parent]?.by == comment.by) {
+      _isResponseCache[comment.id] = true;
+      return true;
+    } else {
+      _isResponseCache[comment.id] = false;
+      return false;
+    }
+  }
+
   @override
   List<Object?> get props => <Object?>[
         item,
@@ -86,5 +135,9 @@ class CommentsState extends Equatable {
         isOfflineReading,
         currentPage,
         comments,
+        matchedComments,
+        inThreadSearchQuery,
+        inThreadSearchAuthor,
+        idToCommentMap,
       ];
 }

lib/cubits/edit/edit_cubit.dart

@@ -12,12 +12,14 @@ part 'edit_state.dart';
 class EditCubit extends HydratedCubit<EditState> {
   EditCubit({DraftCache? draftCache})
       : _draftCache = draftCache ?? locator.get<DraftCache>(),
-        _debouncer = Debouncer(delay: Durations.oneSecond),
+        _debouncer = Debouncer(delay: AppDurations.oneSecond),
         super(const EditState.init());
 
   final DraftCache _draftCache;
   final Debouncer _debouncer;
 
+  void reset() => emit(const EditState.init());
+
   void onReplyTapped(Item item) {
     emit(
       EditState(
@@ -36,14 +38,6 @@ class EditCubit extends HydratedCubit<EditState> {
     );
   }
 
-  void onReplyBoxClosed() {
-    emit(const EditState.init());
-  }
-
-  void onScrolled() {
-    emit(const EditState.init());
-  }
-
   void onReplySubmittedSuccessfully() {
     if (state.replyingTo != null) {
       _draftCache.removeDraft(replyingTo: state.replyingTo!.id);
@@ -65,9 +59,14 @@ class EditCubit extends HydratedCubit<EditState> {
     }
   }
 
-  void deleteDraft() => clear();
-
-  bool called = false;
+  void deleteDraft() {
+    // Remove draft in storage.
+    clear();
+    // Reset cached state.
+    _cachedState = const EditState.init();
+    // Reset to init state;
+    reset();
+  }
 
   @override
   EditState? fromJson(Map<String, dynamic> json) {
@@ -96,6 +95,7 @@ class EditCubit extends HydratedCubit<EditState> {
   Map<String, dynamic>? toJson(EditState state) {
     EditState selected = state;
 
+    // Override previous draft only when current draft is not empty.
     if (state.replyingTo == null ||
         (state.replyingTo?.id != _cachedState.replyingTo?.id &&
             state.text.isNullOrEmpty)) {

lib/cubits/fav/fav_cubit.dart

@@ -1,9 +1,14 @@
+import 'dart:async';
+import 'dart:collection';
+
 import 'package:equatable/equatable.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:hacki/blocs/blocs.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/models/models.dart';
 import 'package:hacki/repositories/repositories.dart';
+import 'package:logger/logger.dart';
 
 part 'fav_state.dart';
 
@@ -12,13 +17,18 @@ class FavCubit extends Cubit<FavState> {
     required AuthBloc authBloc,
     AuthRepository? authRepository,
     PreferenceRepository? preferenceRepository,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
+    HackerNewsWebRepository? hackerNewsWebRepository,
+    Logger? logger,
   })  : _authBloc = authBloc,
         _authRepository = authRepository ?? locator.get<AuthRepository>(),
         _preferenceRepository =
             preferenceRepository ?? locator.get<PreferenceRepository>(),
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
+        _hackerNewsWebRepository =
+            hackerNewsWebRepository ?? locator.get<HackerNewsWebRepository>(),
+        _logger = logger ?? locator.get<Logger>(),
         super(FavState.init()) {
     init();
   }
@@ -26,44 +36,43 @@ class FavCubit extends Cubit<FavState> {
   final AuthBloc _authBloc;
   final AuthRepository _authRepository;
   final PreferenceRepository _preferenceRepository;
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
+  final HackerNewsWebRepository _hackerNewsWebRepository;
+  final Logger _logger;
+  late final StreamSubscription<String>? _usernameSubscription;
   static const int _pageSize = 20;
-  String? _username;
 
   Future<void> init() async {
-    _authBloc.stream.listen((AuthState authState) {
-      if (authState.username != _username) {
-        _preferenceRepository
-            .favList(of: authState.username)
-            .then((List<int> favIds) {
+    _usernameSubscription = _authBloc.stream
+        .map((AuthState event) => event.username)
+        .distinct()
+        .listen((String username) {
+      _preferenceRepository.favList(of: username).then((List<int> favIds) {
+        emit(
+          state.copyWith(
+            favIds: favIds,
+            favItems: <Item>[],
+            currentPage: 0,
+          ),
+        );
+        _hackerNewsRepository
+            .fetchItemsStream(
+              ids: favIds.sublist(0, _pageSize.clamp(0, favIds.length)),
+            )
+            .listen(_onItemLoaded)
+            .onDone(() {
           emit(
             state.copyWith(
-              favIds: favIds,
-              favItems: <Item>[],
-              currentPage: 0,
+              status: Status.success,
             ),
           );
-          _storiesRepository
-              .fetchItemsStream(
-                ids: favIds.sublist(0, _pageSize.clamp(0, favIds.length)),
-              )
-              .listen(_onItemLoaded)
-              .onDone(() {
-            emit(
-              state.copyWith(
-                status: Status.success,
-              ),
-            );
-          });
         });
-
-        _username = authState.username;
-      }
+      });
     });
   }
 
   Future<void> addFav(int id) async {
-    final String username = _authBloc.state.username;
+    if (state.favIds.contains(id)) return;
 
     await _preferenceRepository.addFav(username: username, id: id);
 
@@ -73,7 +82,7 @@ class FavCubit extends Cubit<FavState> {
       ),
     );
 
-    final Item? item = await _storiesRepository.fetchItem(id: id);
+    final Item? item = await _hackerNewsRepository.fetchItem(id: id);
 
     if (item == null) return;
 
@@ -89,9 +98,9 @@ class FavCubit extends Cubit<FavState> {
   }
 
   void removeFav(int id) {
-    final String username = _authBloc.state.username;
-
-    _preferenceRepository.removeFav(username: username, id: id);
+    _preferenceRepository
+      ..removeFav(username: username, id: id)
+      ..removeFav(username: '', id: id);
 
     emit(
       state.copyWith(
@@ -119,7 +128,7 @@ class FavCubit extends Cubit<FavState> {
         upper = len;
       }
 
-      _storiesRepository
+      _hackerNewsRepository
           .fetchItemsStream(
             ids: state.favIds.sublist(
               lower,
@@ -136,8 +145,6 @@ class FavCubit extends Cubit<FavState> {
   }
 
   void refresh() {
-    final String username = _authBloc.state.username;
-
     emit(
       state.copyWith(
         status: Status.inProgress,
@@ -149,7 +156,7 @@ class FavCubit extends Cubit<FavState> {
 
     _preferenceRepository.favList(of: username).then((List<int> favIds) {
       emit(state.copyWith(favIds: favIds));
-      _storiesRepository
+      _hackerNewsRepository
           .fetchItemsStream(
             ids: favIds.sublist(0, _pageSize.clamp(0, favIds.length)),
           )
@@ -167,6 +174,34 @@ class FavCubit extends Cubit<FavState> {
     emit(FavState.init());
   }
 
+  Future<void> merge({
+    required AppExceptionHandler onError,
+    required VoidCallback onSuccess,
+  }) async {
+    if (_authBloc.state.isLoggedIn) {
+      emit(state.copyWith(mergeStatus: Status.inProgress));
+      try {
+        final Iterable<int> ids = await _hackerNewsWebRepository.fetchFavorites(
+          of: _authBloc.state.username,
+        );
+        _logger.d('fetched ${ids.length} favorite items from HN.');
+        final List<int> combinedIds = <int>[...ids, ...state.favIds];
+        final LinkedHashSet<int> mergedIds =
+            LinkedHashSet<int>.from(combinedIds);
+        await _preferenceRepository.overwriteFav(
+          username: username,
+          ids: mergedIds,
+        );
+        emit(state.copyWith(mergeStatus: Status.success));
+        onSuccess();
+        refresh();
+      } on RateLimitedException catch (e) {
+        onError(e);
+        emit(state.copyWith(mergeStatus: Status.failure));
+      }
+    }
+  }
+
   void _onItemLoaded(Item item) {
     emit(
       state.copyWith(
@@ -174,4 +209,14 @@ class FavCubit extends Cubit<FavState> {
       ),
     );
   }
+
+  @override
+  Future<void> close() {
+    _usernameSubscription?.cancel();
+    return super.close();
+  }
+}
+
+extension on FavCubit {
+  String get username => _authBloc.state.username;
 }

lib/cubits/fav/fav_state.dart

@@ -5,6 +5,7 @@ class FavState extends Equatable {
     required this.favIds,
     required this.favItems,
     required this.status,
+    required this.mergeStatus,
     required this.currentPage,
   });
 
@@ -12,23 +13,27 @@ class FavState extends Equatable {
       : favIds = <int>[],
         favItems = <Item>[],
         status = Status.idle,
+        mergeStatus = Status.idle,
         currentPage = 0;
 
   final List<int> favIds;
   final List<Item> favItems;
   final Status status;
+  final Status mergeStatus;
   final int currentPage;
 
   FavState copyWith({
     List<int>? favIds,
     List<Item>? favItems,
     Status? status,
+    Status? mergeStatus,
     int? currentPage,
   }) {
     return FavState(
       favIds: favIds ?? this.favIds,
       favItems: favItems ?? this.favItems,
       status: status ?? this.status,
+      mergeStatus: mergeStatus ?? this.mergeStatus,
       currentPage: currentPage ?? this.currentPage,
     );
   }
@@ -36,6 +41,7 @@ class FavState extends Equatable {
   @override
   List<Object?> get props => <Object?>[
         status,
+        mergeStatus,
         currentPage,
         favIds,
         favItems,

lib/cubits/history/history_cubit.dart

@@ -10,16 +10,16 @@ part 'history_state.dart';
 class HistoryCubit extends Cubit<HistoryState> {
   HistoryCubit({
     required AuthBloc authBloc,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
   })  : _authBloc = authBloc,
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         super(HistoryState.init()) {
     init();
   }
 
   final AuthBloc _authBloc;
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
   static const int _pageSize = 20;
 
   void init() {
@@ -27,7 +27,7 @@ class HistoryCubit extends Cubit<HistoryState> {
       if (authState.isLoggedIn) {
         final String username = authState.username;
 
-        _storiesRepository
+        _hackerNewsRepository
             .fetchSubmitted(userId: username)
             .then((List<int>? submittedIds) {
           emit(
@@ -38,7 +38,7 @@ class HistoryCubit extends Cubit<HistoryState> {
             ),
           );
           if (submittedIds != null) {
-            _storiesRepository
+            _hackerNewsRepository
                 .fetchItemsStream(
                   ids: submittedIds.sublist(
                     0,
@@ -66,7 +66,7 @@ class HistoryCubit extends Cubit<HistoryState> {
         upper = len;
       }
 
-      _storiesRepository
+      _hackerNewsRepository
           .fetchItemsStream(
             ids: state.submittedIds.sublist(
               lower,
@@ -93,12 +93,12 @@ class HistoryCubit extends Cubit<HistoryState> {
       ),
     );
 
-    _storiesRepository
+    _hackerNewsRepository
         .fetchSubmitted(userId: username)
         .then((List<int>? submittedIds) {
       emit(state.copyWith(submittedIds: submittedIds));
       if (submittedIds != null) {
-        _storiesRepository
+        _hackerNewsRepository
             .fetchItemsStream(
               ids: submittedIds.sublist(
                 0,

lib/cubits/notification/notification_cubit.dart

@@ -16,23 +16,26 @@ class NotificationCubit extends Cubit<NotificationState> {
   NotificationCubit({
     required AuthBloc authBloc,
     required PreferenceCubit preferenceCubit,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
     PreferenceRepository? preferenceRepository,
     SembastRepository? sembastRepository,
   })  : _authBloc = authBloc,
         _preferenceCubit = preferenceCubit,
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         _preferenceRepository =
             preferenceRepository ?? locator.get<PreferenceRepository>(),
         _sembastRepository =
             sembastRepository ?? locator.get<SembastRepository>(),
         super(NotificationState.init()) {
-    _authBloc.stream.listen((AuthState authState) {
-      if (authState.isLoggedIn && authState.username != _username) {
+    _authBloc.stream
+        .map((AuthState event) => event.username)
+        .distinct()
+        .listen((String username) {
+      if (username.isNotEmpty) {
         // Get the user setting.
         if (_preferenceCubit.state.notificationEnabled) {
-          Future<void>.delayed(Durations.twoSeconds, init);
+          Future<void>.delayed(AppDurations.twoSeconds, init);
         }
 
         // Listen for setting changes in the future.
@@ -44,9 +47,7 @@ class NotificationCubit extends Cubit<NotificationState> {
             _timer?.cancel();
           }
         });
-
-        _username = authState.username;
-      } else if (!authState.isLoggedIn) {
+      } else {
         emit(NotificationState.init());
       }
     });
@@ -54,10 +55,9 @@ class NotificationCubit extends Cubit<NotificationState> {
 
   final AuthBloc _authBloc;
   final PreferenceCubit _preferenceCubit;
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
   final PreferenceRepository _preferenceRepository;
   final SembastRepository _sembastRepository;
-  String? _username;
   Timer? _timer;
 
   static const Duration _refreshInterval = Duration(minutes: 5);
@@ -82,7 +82,7 @@ class NotificationCubit extends Cubit<NotificationState> {
 
     for (final int id in commentsToBeLoaded) {
       Comment? comment = await _sembastRepository.getComment(id: id);
-      comment ??= await _storiesRepository.fetchComment(id: id);
+      comment ??= await _hackerNewsRepository.fetchComment(id: id);
       if (comment != null) {
         emit(
           state.copyWith(
@@ -160,7 +160,7 @@ class NotificationCubit extends Cubit<NotificationState> {
 
       for (final int id in commentsToBeLoaded) {
         Comment? comment = await _sembastRepository.getComment(id: id);
-        comment ??= await _storiesRepository.fetchComment(id: id);
+        comment ??= await _hackerNewsRepository.fetchComment(id: id);
         if (comment != null) {
           emit(state.copyWith(comments: <Comment>[...state.comments, comment]));
         }
@@ -184,7 +184,7 @@ class NotificationCubit extends Cubit<NotificationState> {
   }
 
   Future<void> _fetchReplies() {
-    return _storiesRepository
+    return _hackerNewsRepository
         .fetchSubmitted(userId: _authBloc.state.username)
         .then((List<int>? submittedItems) async {
       if (submittedItems != null) {
@@ -194,7 +194,9 @@ class NotificationCubit extends Cubit<NotificationState> {
         );
 
         for (final int id in subscribedItems) {
-          await _storiesRepository.fetchItem(id: id).then((Item? item) async {
+          await _hackerNewsRepository
+              .fetchItem(id: id)
+              .then((Item? item) async {
             final List<int> kids = item?.kids ?? <int>[];
             final List<int> previousKids =
                 (await _sembastRepository.kids(of: id)) ?? <int>[];
@@ -216,7 +218,7 @@ class NotificationCubit extends Cubit<NotificationState> {
                       ...state.unreadCommentsIds,
                     ]..sort((int lhs, int rhs) => rhs.compareTo(lhs)),
                   );
-                  await _storiesRepository
+                  await _hackerNewsRepository
                       .fetchComment(id: newCommentId)
                       .then((Comment? comment) {
                     if (comment != null && !comment.dead && !comment.deleted) {

lib/cubits/pin/pin_cubit.dart

@@ -1,5 +1,6 @@
 import 'package:bloc/bloc.dart';
 import 'package:equatable/equatable.dart';
+import 'package:flutter/foundation.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/models/models.dart';
 import 'package:hacki/repositories/repositories.dart';
@@ -9,28 +10,33 @@ part 'pin_state.dart';
 class PinCubit extends Cubit<PinState> {
   PinCubit({
     PreferenceRepository? preferenceRepository,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
   })  : _preferenceRepository =
             preferenceRepository ?? locator.get<PreferenceRepository>(),
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         super(PinState.init()) {
     init();
   }
 
   final PreferenceRepository _preferenceRepository;
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
 
   void init() {
     emit(PinState.init());
     _preferenceRepository.pinnedStoriesIds.then((List<int> ids) {
       emit(state.copyWith(pinnedStoriesIds: ids));
 
-      _storiesRepository.fetchStoriesStream(ids: ids).listen(_onStoryFetched);
+      _hackerNewsRepository
+          .fetchStoriesStream(ids: ids)
+          .listen(_onStoryFetched);
     }).whenComplete(() => emit(state.copyWith(status: Status.success)));
   }
 
-  void pinStory(Story story) {
+  void pinStory(
+    Story story, {
+    VoidCallback? onDone,
+  }) {
     if (!state.pinnedStoriesIds.contains(story.id)) {
       emit(
         state.copyWith(
@@ -39,10 +45,14 @@ class PinCubit extends Cubit<PinState> {
         ),
       );
       _preferenceRepository.updatePinnedStoriesIds(state.pinnedStoriesIds);
+      onDone?.call();
     }
   }
 
-  void unpinStory(Story story) {
+  void unpinStory(
+    Story story, {
+    VoidCallback? onDone,
+  }) {
     emit(
       state.copyWith(
         pinnedStoriesIds: <int>[...state.pinnedStoriesIds]..remove(story.id),
@@ -50,6 +60,7 @@ class PinCubit extends Cubit<PinState> {
       ),
     );
     _preferenceRepository.updatePinnedStoriesIds(state.pinnedStoriesIds);
+    onDone?.call();
   }
 
   void refresh() {

lib/cubits/poll/poll_cubit.dart

@@ -11,13 +11,13 @@ part 'poll_state.dart';
 class PollCubit extends Cubit<PollState> {
   PollCubit({
     required Story story,
-    StoriesRepository? storiesRepository,
+    HackerNewsRepository? hackerNewsRepository,
   })  : _story = story,
-        _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+        _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         super(PollState.init());
 
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
   final Story _story;
 
   Future<void> init({
@@ -33,7 +33,7 @@ class PollCubit extends Cubit<PollState> {
 
     if (pollOptionsIds.isEmpty || refresh) {
       final Story? updatedStory =
-          await _storiesRepository.fetchStory(id: _story.id);
+          await _hackerNewsRepository.fetchStory(id: _story.id);
 
       if (updatedStory != null) {
         pollOptionsIds = updatedStory.parts;
@@ -47,7 +47,7 @@ class PollCubit extends Cubit<PollState> {
     }
 
     if (pollOptionsIds.isNotEmpty) {
-      final List<PollOption> pollOptions = (await _storiesRepository
+      final List<PollOption> pollOptions = (await _hackerNewsRepository
               .fetchPollOptionsStream(ids: pollOptionsIds)
               .toSet())
           .toList();

lib/cubits/post/post_cubit.dart

@@ -16,6 +16,7 @@ class PostCubit extends Cubit<PostState> {
 
   Future<void> post({required String text, required int to}) async {
     emit(state.copyWith(status: Status.inProgress));
+
     final bool successful = await _postRepository.comment(
       parentId: to,
       text: text,
@@ -42,4 +43,13 @@ class PostCubit extends Cubit<PostState> {
   void reset() {
     emit(state.copyWith(status: Status.idle));
   }
+
+  @Deprecated('For debugging only')
+  Future<bool> getFakeResult() async {
+    final bool result = await Future<bool>.delayed(
+      const Duration(seconds: 2),
+      () => true,
+    );
+    return result;
+  }
 }

lib/cubits/preference/preference_cubit.dart

@@ -1,5 +1,7 @@
 import 'package:bloc/bloc.dart';
 import 'package:equatable/equatable.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_material_color_picker/flutter_material_color_picker.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/extensions/extensions.dart';
 import 'package:hacki/models/models.dart';
@@ -41,6 +43,16 @@ class PreferenceCubit extends Cubit<PreferenceState> {
         return null;
       });
     }
+
+    for (final DoublePreference p
+        in Preference.allPreferences.whereType<DoublePreference>()) {
+      initPreference<double>(p).then<double?>((double? value) {
+        final Preference<dynamic> updatedPreference = p.copyWith(val: value);
+        emit(state.copyWithPreference(updatedPreference));
+
+        return null;
+      });
+    }
   }
 
   Future<T?> initPreference<T>(Preference<T> preference) async {
@@ -48,6 +60,10 @@ class PreferenceCubit extends Cubit<PreferenceState> {
       case int:
         final int? value = await _preferenceRepository.getInt(preference.key);
         return value as T?;
+      case double:
+        final double? value =
+            await _preferenceRepository.getDouble(preference.key);
+        return value as T?;
       case bool:
         final bool? value = await _preferenceRepository.getBool(preference.key);
         return value as T?;
@@ -56,19 +72,27 @@ class PreferenceCubit extends Cubit<PreferenceState> {
     }
   }
 
-  void update<T>(Preference<T> preference, {required T to}) {
-    final T value = to;
-    final Preference<T> updatedPreference = preference.copyWith(val: value);
+  void update<T>(Preference<T> preference) {
+    _logger.i('updating $preference to ${preference.val}');
 
-    _logger.i('updating $preference to $value');
-
-    emit(state.copyWithPreference(updatedPreference));
+    emit(state.copyWithPreference(preference));
 
     switch (T) {
       case int:
-        _preferenceRepository.setInt(preference.key, value as int);
+        _preferenceRepository.setInt(
+          preference.key,
+          preference.val as int,
+        );
+      case double:
+        _preferenceRepository.setDouble(
+          preference.key,
+          preference.val as double,
+        );
       case bool:
-        _preferenceRepository.setBool(preference.key, value as bool);
+        _preferenceRepository.setBool(
+          preference.key,
+          preference.val as bool,
+        );
       default:
         throw UnimplementedError();
     }

lib/cubits/preference/preference_state.dart

@@ -54,8 +54,6 @@ class PreferenceState extends Equatable {
 
   bool get eyeCandyEnabled => _isOn<EyeCandyModePreference>();
 
-  bool get trueDarkEnabled => _isOn<TrueDarkModePreference>();
-
   bool get readerEnabled => _isOn<ReaderModePreference>();
 
   bool get markReadStoriesEnabled => _isOn<MarkReadStoriesModePreference>();
@@ -70,6 +68,25 @@ class PreferenceState extends Equatable {
 
   bool get autoScrollEnabled => _isOn<AutoScrollModePreference>();
 
+  bool get customTabEnabled => _isOn<CustomTabPreference>();
+
+  bool get manualPaginationEnabled => _isOn<ManualPaginationPreference>();
+
+  bool get trueDarkModeEnabled => _isOn<TrueDarkModePreference>();
+
+  bool get hapticFeedbackEnabled => _isOn<HapticFeedbackPreference>();
+
+  bool get devModeEnabled => _isOn<DevMode>();
+
+  double get textScaleFactor =>
+      preferences.singleWhereType<TextScaleFactorPreference>().val;
+
+  MaterialColor get appColor {
+    return materialColors.elementAt(
+      preferences.singleWhereType<AppColorPreference>().val,
+    ) as MaterialColor;
+  }
+
   List<StoryType> get tabs {
     final String result =
         preferences.singleWhereType<TabOrderPreference>().val.toString();

lib/cubits/search/search_cubit.dart

@@ -102,6 +102,18 @@ class SearchCubit extends Cubit<SearchState> {
     search(state.params.query);
   }
 
+  void onExactMatchToggled() {
+    emit(
+      state.copyWith(
+        params: state.params.copyWith(
+          exactMatch: !state.params.exactMatch,
+        ),
+      ),
+    );
+
+    search(state.params.query);
+  }
+
   void onDateTimeRangeUpdated(DateTime start, DateTime end) {
     final DateTime updatedStart = start.copyWith(
       second: 0,

lib/cubits/tab/tab_cubit.dart

@@ -38,8 +38,7 @@ class TabCubit extends Cubit<TabState> {
     // Check to make sure there's no duplicate.
     if (updatedTabs.toSet().length == StoryType.values.length) {
       _preferenceCubit.update<int>(
-        TabOrderPreference(),
-        to: StoryType.convertToSettingsValue(updatedTabs),
+        TabOrderPreference(val: StoryType.convertToSettingsValue(updatedTabs)),
       );
     }
   }

lib/cubits/user/user_cubit.dart

@@ -7,16 +7,16 @@ import 'package:hacki/repositories/repositories.dart';
 part 'user_state.dart';
 
 class UserCubit extends Cubit<UserState> {
-  UserCubit({StoriesRepository? storiesRepository})
-      : _storiesRepository =
-            storiesRepository ?? locator.get<StoriesRepository>(),
+  UserCubit({HackerNewsRepository? hackerNewsRepository})
+      : _hackerNewsRepository =
+            hackerNewsRepository ?? locator.get<HackerNewsRepository>(),
         super(const UserState.init());
 
-  final StoriesRepository _storiesRepository;
+  final HackerNewsRepository _hackerNewsRepository;
 
   void init({required String userId}) {
     emit(state.copyWith(status: Status.inProgress));
-    _storiesRepository.fetchUser(id: userId).then((User? user) {
+    _hackerNewsRepository.fetchUser(id: userId).then((User? user) {
       emit(
         state.copyWith(
           user: user ?? User.emptyWithId(userId),

lib/extensions/context_extension.dart

@@ -3,7 +3,6 @@ import 'dart:math';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:hacki/config/constants.dart';
-import 'package:hacki/styles/styles.dart';
 
 extension ContextExtension on BuildContext {
   T? tryRead<T>() {
@@ -21,22 +20,37 @@ extension ContextExtension on BuildContext {
   }) {
     ScaffoldMessenger.of(this).showSnackBar(
       SnackBar(
-        backgroundColor: Palette.deepOrange,
-        content: Text(content),
+        backgroundColor: Theme.of(this).colorScheme.primary,
+        content: Text(
+          content,
+          style: TextStyle(
+            color: Theme.of(this).colorScheme.onPrimary,
+          ),
+        ),
         action: action != null && label != null
             ? SnackBarAction(
                 label: label,
                 onPressed: action,
-                textColor: Theme.of(this).textTheme.bodyLarge?.color,
+                textColor: Theme.of(this).colorScheme.onPrimary,
               )
             : null,
       ),
     );
   }
 
-  void showErrorSnackBar() => showSnackBar(
-        content: Constants.errorMessage,
-      );
+  void showErrorSnackBar([String? message]) {
+    ScaffoldMessenger.of(this).showSnackBar(
+      SnackBar(
+        backgroundColor: Theme.of(this).colorScheme.errorContainer,
+        content: Text(
+          message ?? Constants.errorMessage,
+          style: TextStyle(
+            color: Theme.of(this).colorScheme.onErrorContainer,
+          ),
+        ),
+      ),
+    );
+  }
 
   Rect? get rect {
     final RenderBox? box = findRenderObject() as RenderBox?;
@@ -81,4 +95,8 @@ extension ContextExtension on BuildContext {
   int get storyTileMaxLines {
     return _storyTileMaxLines;
   }
+
+  double get topPadding {
+    return MediaQuery.of(this).padding.top + kToolbarHeight;
+  }
 }

lib/extensions/extensions.dart

@@ -1,9 +1,9 @@
 export 'context_extension.dart';
 export 'date_time_extension.dart';
 export 'int_extension.dart';
+export 'item_action_mixin.dart';
 export 'list_extension.dart';
 export 'object_extension.dart';
 export 'set_extension.dart';
-export 'state_extension.dart';
 export 'string_extension.dart';
 export 'widget_extension.dart';

lib/extensions/item_action_mixin.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:go_router/go_router.dart';
 import 'package:hacki/blocs/auth/auth_bloc.dart';
+import 'package:hacki/config/constants.dart';
 import 'package:hacki/cubits/cubits.dart';
 import 'package:hacki/extensions/extensions.dart';
 import 'package:hacki/models/models.dart';
@@ -12,7 +13,8 @@ import 'package:hacki/styles/styles.dart';
 import 'package:hacki/utils/utils.dart';
 import 'package:share_plus/share_plus.dart';
 
-extension StateExtension on State {
+@optionalTypeArgs
+mixin ItemActionMixin<T extends StatefulWidget> on State<T> {
   void showSnackBar({
     required String content,
     VoidCallback? action,
@@ -25,7 +27,8 @@ extension StateExtension on State {
     );
   }
 
-  void showErrorSnackBar() => context.showErrorSnackBar();
+  void showErrorSnackBar([String? message]) =>
+      context.showErrorSnackBar(message);
 
   Future<void>? goToItemScreen({
     required ItemScreenArgs args,
@@ -36,10 +39,7 @@ extension StateExtension on State {
     if (splitViewEnabled && !forceNewScreen) {
       context.read<SplitViewCubit>().updateItemScreenArgs(args);
     } else {
-      context.push(
-        '/${ItemScreen.routeName}',
-        extra: args,
-      );
+      context.push('/${ItemScreen.routeName}', extra: args);
     }
 
     return Future<void>.value();
@@ -105,31 +105,26 @@ extension StateExtension on State {
         context: context,
         builder: (BuildContext context) {
           return SafeArea(
-            child: ColoredBox(
-              color: Theme.of(context).canvasColor,
-              child: Material(
-                child: Column(
-                  mainAxisSize: MainAxisSize.min,
-                  children: <Widget>[
-                    ListTile(
-                      onTap: () => context.pop(item.url),
-                      title: const Text('Link to article'),
-                    ),
-                    ListTile(
-                      onTap: () => context.pop(
-                        'https://news.ycombinator.com/item?id=${item.id}',
-                      ),
-                      title: const Text('Link to HN'),
-                    ),
-                  ],
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              children: <Widget>[
+                ListTile(
+                  onTap: () => context.pop(item.url),
+                  title: const Text('Link to article'),
                 ),
-              ),
+                ListTile(
+                  onTap: () => context.pop(
+                    '${Constants.hackerNewsItemLinkPrefix}${item.id}',
+                  ),
+                  title: const Text('Link to HN'),
+                ),
+              ],
             ),
           );
         },
       );
     } else {
-      linkToShare = 'https://news.ycombinator.com/item?id=${item.id}';
+      linkToShare = '${Constants.hackerNewsItemLinkPrefix}${item.id}';
     }
 
     if (linkToShare != null) {

lib/extensions/widget_extension.dart

@@ -2,21 +2,19 @@ import 'package:flutter/material.dart';
 import 'package:hacki/config/constants.dart';
 import 'package:hacki/models/models.dart';
 import 'package:hacki/screens/widgets/custom_linkify/custom_linkify.dart';
+import 'package:hacki/styles/styles.dart';
 import 'package:hacki/utils/utils.dart';
 
-extension WidgetModifier on Widget {
-  Widget padded([EdgeInsetsGeometry value = const EdgeInsets.all(12)]) {
-    return Padding(
-      padding: value,
-      child: this,
-    );
-  }
-
+extension ContextMenuBuilder on Widget {
   Widget contextMenuBuilder(
     BuildContext context,
     EditableTextState editableTextState, {
     required Item item,
   }) {
+    if (item is! Buildable) {
+      return const SizedBox.shrink();
+    }
+
     final int start = editableTextState.textEditingValue.selection.base.offset;
     final int end = editableTextState.textEditingValue.selection.end;
 
@@ -25,39 +23,24 @@ extension WidgetModifier on Widget {
     ];
 
     if (start != -1 && end != -1) {
-      String selectedText = item.text.substring(start, end);
-
-      if (item is Buildable) {
-        final Iterable<EmphasisElement> emphasisElements =
-            (item as Buildable).elements.whereType<EmphasisElement>();
-
-        int count = 1;
-        while (selectedText.contains(' ') && count <= emphasisElements.length) {
-          final int s = (start + count * 2).clamp(0, item.text.length);
-          final int e = (end + count * 2).clamp(0, item.text.length);
-          selectedText = item.text.substring(s, e);
-          count++;
-        }
-
-        count = 1;
-        while (selectedText.contains(' ') && count <= emphasisElements.length) {
-          final int s = (start - count * 2).clamp(0, item.text.length);
-          final int e = (end - count * 2).clamp(0, item.text.length);
-          selectedText = item.text.substring(s, e);
-          count++;
-        }
-      }
+      final String text = (item as Buildable)
+          .elements
+          .map((LinkifyElement e) => e.text)
+          .reduce((String value, String e) => '$value$e');
+      final String selectedText = text.substring(start, end);
 
       items.addAll(<ContextMenuButtonItem>[
         ContextMenuButtonItem(
           onPressed: () => LinkUtil.launch(
             '''${Constants.wikipediaLink}$selectedText''',
+            context,
           ),
           label: 'Wikipedia',
         ),
         ContextMenuButtonItem(
           onPressed: () => LinkUtil.launch(
             '''${Constants.wiktionaryLink}$selectedText''',
+            context,
           ),
           label: 'Wiktionary',
         ),
@@ -70,3 +53,14 @@ extension WidgetModifier on Widget {
     );
   }
 }
+
+extension WidgetModifier on Widget {
+  Widget padded([
+    EdgeInsetsGeometry value = const EdgeInsets.all(Dimens.pt12),
+  ]) {
+    return Padding(
+      padding: value,
+      child: this,
+    );
+  }
+}

lib/main.dart

@@ -13,19 +13,20 @@ import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:flutter_siri_suggestions/flutter_siri_suggestions.dart';
 import 'package:hacki/blocs/blocs.dart';
+import 'package:hacki/config/constants.dart';
 import 'package:hacki/config/custom_router.dart';
 import 'package:hacki/config/locator.dart';
 import 'package:hacki/cubits/cubits.dart';
-import 'package:hacki/models/models.dart';
 import 'package:hacki/services/fetcher.dart';
 import 'package:hacki/styles/styles.dart';
+import 'package:hacki/utils/haptic_feedback_util.dart';
 import 'package:hacki/utils/theme_util.dart';
 import 'package:hive/hive.dart';
 import 'package:hydrated_bloc/hydrated_bloc.dart';
 import 'package:logger/logger.dart';
 import 'package:path_provider/path_provider.dart';
 import 'package:rxdart/rxdart.dart' show BehaviorSubject;
-import 'package:shared_preferences/shared_preferences.dart';
+import 'package:visibility_detector/visibility_detector.dart';
 import 'package:workmanager/workmanager.dart';
 
 // For receiving payload event from local notifications.
@@ -131,38 +132,28 @@ Future<void> main({bool testing = false}) async {
   }
 
   final AdaptiveThemeMode? savedThemeMode = await AdaptiveTheme.getThemeMode();
-  final SharedPreferences prefs = await SharedPreferences.getInstance();
-  final bool trueDarkMode =
-      prefs.getBool(const TrueDarkModePreference().key) ?? false;
-  final Font font = Font.values.elementAt(
-    prefs.getInt(FontPreference().key) ?? Font.roboto.index,
-  );
 
-  //Uncomment this line to log events from bloc/cubit.
-  //Bloc.observer = CustomBlocObserver();
+  // Uncomment this line to log events from bloc/cubit.
+  // Bloc.observer = CustomBlocObserver();
 
   HydratedBloc.storage = storage;
 
+  VisibilityDetectorController.instance.updateInterval = AppDurations.ms200;
+
   runApp(
     HackiApp(
       savedThemeMode: savedThemeMode,
-      trueDarkMode: trueDarkMode,
-      font: font,
     ),
   );
 }
 
 class HackiApp extends StatelessWidget {
   const HackiApp({
-    required this.trueDarkMode,
-    required this.font,
     super.key,
     this.savedThemeMode,
   });
 
   final AdaptiveThemeMode? savedThemeMode;
-  final Font font;
-  final bool trueDarkMode;
 
   @override
   Widget build(BuildContext context) {
@@ -239,56 +230,128 @@ class HackiApp extends StatelessWidget {
           )..init(),
         ),
       ],
-      child: AdaptiveTheme(
-        light: ThemeData(
-          primarySwatch: Palette.orange,
-          fontFamily: font.name,
-        ),
-        dark: ThemeData(
-          brightness: Brightness.dark,
-          primarySwatch: Palette.orange,
-          canvasColor: trueDarkMode ? Palette.black : null,
-          fontFamily: font.name,
-        ),
-        initial: savedThemeMode ?? AdaptiveThemeMode.system,
-        builder: (ThemeData theme, ThemeData darkTheme) {
-          final ThemeData trueDarkTheme = ThemeData(
-            brightness: Brightness.dark,
-            primarySwatch: Palette.orange,
-            canvasColor: Palette.black,
-            fontFamily: font.name,
-          );
-          return FutureBuilder<AdaptiveThemeMode?>(
-            future: AdaptiveTheme.getThemeMode(),
-            builder: (
-              BuildContext context,
-              AsyncSnapshot<AdaptiveThemeMode?> snapshot,
-            ) {
-              final AdaptiveThemeMode? mode = snapshot.data;
-              ThemeUtil.updateStatusBarSetting(
-                SchedulerBinding.instance.platformDispatcher.platformBrightness,
-                mode,
-              );
-              return BlocBuilder<PreferenceCubit, PreferenceState>(
-                buildWhen:
-                    (PreferenceState previous, PreferenceState current) =>
-                        previous.trueDarkEnabled != current.trueDarkEnabled,
-                builder: (BuildContext context, PreferenceState prefState) {
-                  final bool useTrueDark = prefState.trueDarkEnabled &&
-                      (mode == AdaptiveThemeMode.dark ||
+      child: BlocConsumer<PreferenceCubit, PreferenceState>(
+        listenWhen: (PreferenceState previous, PreferenceState current) =>
+            previous.hapticFeedbackEnabled != current.hapticFeedbackEnabled,
+        listener: (_, PreferenceState state) {
+          HapticFeedbackUtil.enabled = state.hapticFeedbackEnabled;
+        },
+        buildWhen: (PreferenceState previous, PreferenceState current) =>
+            previous.appColor != current.appColor ||
+            previous.font != current.font ||
+            previous.textScaleFactor != current.textScaleFactor ||
+            previous.trueDarkModeEnabled != current.trueDarkModeEnabled,
+        builder: (BuildContext context, PreferenceState state) {
+          return AdaptiveTheme(
+            key: ValueKey<String>(
+              '''${state.appColor}${state.font}${state.trueDarkModeEnabled}''',
+            ),
+            light: ThemeData(
+              primaryColor: state.appColor,
+              colorScheme: ColorScheme.fromSwatch(
+                primarySwatch: state.appColor,
+              ),
+              fontFamily: state.font.name,
+            ),
+            dark: ThemeData(
+              brightness: Brightness.dark,
+              primaryColor: state.appColor,
+              colorScheme: ColorScheme.fromSwatch(
+                primarySwatch: state.appColor,
+                brightness: Brightness.dark,
+              ),
+              fontFamily: state.font.name,
+            ),
+            initial: savedThemeMode ?? AdaptiveThemeMode.system,
+            builder: (ThemeData theme, ThemeData darkTheme) {
+              return FutureBuilder<AdaptiveThemeMode?>(
+                future: AdaptiveTheme.getThemeMode(),
+                builder: (
+                  BuildContext context,
+                  AsyncSnapshot<AdaptiveThemeMode?> snapshot,
+                ) {
+                  final AdaptiveThemeMode? mode = snapshot.data;
+                  ThemeUtil.updateStatusBarSetting(
+                    SchedulerBinding
+                        .instance.platformDispatcher.platformBrightness,
+                    mode,
+                  );
+                  final bool isDarkModeEnabled =
+                      mode == AdaptiveThemeMode.dark ||
                           (mode == AdaptiveThemeMode.system &&
                               View.of(context)
                                       .platformDispatcher
                                       .platformBrightness ==
-                                  Brightness.dark));
+                                  Brightness.dark);
+                  final ColorScheme colorScheme = ColorScheme.fromSeed(
+                    brightness:
+                        isDarkModeEnabled ? Brightness.dark : Brightness.light,
+                    seedColor: state.appColor,
+                    background: isDarkModeEnabled && state.trueDarkModeEnabled
+                        ? Palette.black
+                        : null,
+                  );
                   return FeatureDiscovery(
-                    child: MaterialApp.router(
-                      title: 'Hacki',
-                      debugShowCheckedModeBanner: false,
-                      theme: (useTrueDark ? trueDarkTheme : theme).copyWith(
-                        useMaterial3: false,
+                    child: MediaQuery(
+                      data: state.textScaleFactor == 1
+                          ? MediaQuery.of(context)
+                          : MediaQuery.of(context).copyWith(
+                              textScaler: TextScaler.linear(
+                                state.textScaleFactor,
+                              ),
+                            ),
+                      child: MaterialApp.router(
+                        title: 'Hacki',
+                        debugShowCheckedModeBanner: false,
+                        theme: ThemeData(
+                          colorScheme: colorScheme,
+                          fontFamily: state.font.name,
+                          dividerTheme: DividerThemeData(
+                            color: Palette.grey.withOpacity(0.2),
+                          ),
+                          switchTheme: SwitchThemeData(
+                            trackColor: MaterialStateProperty.resolveWith(
+                              (Set<MaterialState> states) {
+                                if (states.contains(MaterialState.selected)) {
+                                  return colorScheme.primary.withOpacity(0.6);
+                                } else {
+                                  return Palette.grey.withOpacity(0.2);
+                                }
+                              },
+                            ),
+                          ),
+                          bottomSheetTheme: const BottomSheetThemeData(
+                            modalElevation: 8,
+                            clipBehavior: Clip.hardEdge,
+                            shadowColor: Palette.black,
+                          ),
+                          inputDecorationTheme: InputDecorationTheme(
+                            enabledBorder: UnderlineInputBorder(
+                              borderSide: BorderSide(
+                                color: isDarkModeEnabled
+                                    ? Palette.white
+                                    : Palette.black,
+                              ),
+                            ),
+                          ),
+                          sliderTheme: SliderThemeData(
+                            inactiveTrackColor:
+                                colorScheme.primary.withOpacity(0.5),
+                            activeTrackColor: colorScheme.primary,
+                            thumbColor: colorScheme.primary,
+                          ),
+                          outlinedButtonTheme: OutlinedButtonThemeData(
+                            style: ButtonStyle(
+                              side: MaterialStateBorderSide.resolveWith(
+                                (_) => const BorderSide(
+                                  color: Palette.grey,
+                                ),
+                              ),
+                            ),
+                          ),
+                        ),
+                        routerConfig: router,
                       ),
-                      routerConfig: router,
                     ),
                   );
                 },

lib/models/app_exception.dart

@@ -0,0 +1,36 @@
+typedef AppExceptionHandler = void Function(AppException);
+
+class AppException implements Exception {
+  AppException({
+    required this.message,
+    this.stackTrace,
+  });
+
+  final String message;
+  final StackTrace? stackTrace;
+}
+
+class RateLimitedException extends AppException {
+  RateLimitedException() : super(message: 'Rate limited...');
+}
+
+class RateLimitedWithFallbackException extends AppException {
+  RateLimitedWithFallbackException()
+      : super(message: 'Rate limited, fetching from API instead...');
+}
+
+class PossibleParsingException extends AppException {
+  PossibleParsingException({
+    required this.itemId,
+  }) : super(message: 'Possible parsing failure...');
+
+  final int itemId;
+}
+
+class BrowserNotRunningException extends AppException {
+  BrowserNotRunningException() : super(message: 'Browser not running...');
+}
+
+class GenericException extends AppException {
+  GenericException() : super(message: 'Something went wrong...');
+}

lib/models/comments_order.dart

@@ -6,4 +6,7 @@ enum CommentsOrder {
   const CommentsOrder(this.description);
 
   final String description;
+
+  @override
+  String toString() => description;
 }

lib/models/discoverable_feature.dart

@@ -0,0 +1,52 @@
+enum DiscoverableFeature {
+  addStoryToFavList(
+    featureId: 'add_story_to_fav_list',
+    title: 'Fav a Story',
+    description: '''Add it to your favorites.''',
+  ),
+  openStoryInWebView(
+    featureId: 'open_story_in_web_view',
+    title: 'Open in Browser',
+    description: '''You can tap here to open this story in browser.''',
+  ),
+  login(
+    featureId: 'log_in',
+    title: 'Log in for more',
+    description:
+        '''Log in using your Hacker News account to check out stories and comments you have posted in the past, and get in-app notification when there is new reply to your comments or stories.''',
+  ),
+  pinToTop(
+    featureId: 'pin_to_top',
+    title: 'Pin a Story',
+    description:
+        '''Pin this story to the top of your home screen so that you can come back later.''',
+  ),
+  jumpUpButton(
+    featureId: 'jump_up_button_with_long_press',
+    title: 'Shortcut',
+    description:
+        '''Tapping on this button will take you to the previous root level comment.\n\nLong press on it to jump to the very beginning of this thread.''',
+  ),
+  jumpDownButton(
+    featureId: 'jump_down_button_with_long_press',
+    title: 'Shortcut',
+    description:
+        '''Tapping on this button will take you to the next root level comment.\n\nLong press on it to jump to the end of this thread.''',
+  ),
+  searchInThread(
+    featureId: 'search_in_thread',
+    title: 'Search in Thread',
+    description: '''Search for comments in this thread.''',
+  );
+
+  const DiscoverableFeature({
+    required this.featureId,
+    required this.title,
+    required this.description,
+  });
+
+  /// Feature ids for feature discovery.
+  final String featureId;
+  final String title;
+  final String description;
+}

lib/models/fetch_mode.dart

@@ -5,4 +5,7 @@ enum FetchMode {
   const FetchMode(this.description);
 
   final String description;
+
+  @override
+  String toString() => description;
 }

lib/models/font.dart

@@ -3,26 +3,11 @@ enum Font {
   robotoSlab('Roboto Slab', isSerif: true),
   ubuntu('Ubuntu'),
   ubuntuMono('Ubuntu Mono'),
-  notoSerif('Noto Serif', isSerif: true);
+  notoSerif('Noto Serif', isSerif: true),
+  exo2('Exo 2');
 
   const Font(this.uiLabel, {this.isSerif = false});
 
   final String uiLabel;
   final bool isSerif;
-
-  static Font fromString(String? val) {
-    switch (val) {
-      case 'robotoSlab':
-        return Font.robotoSlab;
-      case 'ubuntu':
-        return Font.ubuntu;
-      case 'ubuntuMono':
-        return Font.ubuntuMono;
-      case 'notoSerif':
-        return Font.notoSerif;
-      case 'roboto':
-      default:
-        return Font.roboto;
-    }
-  }
 }

lib/models/item/buildable_comment.dart

@@ -17,6 +17,7 @@ class BuildableComment extends Comment with Buildable {
     required super.deleted,
     required super.hidden,
     required super.level,
+    required super.isFromCache,
     required this.elements,
   });
 
@@ -33,6 +34,7 @@ class BuildableComment extends Comment with Buildable {
           deleted: comment.deleted,
           level: comment.level,
           hidden: comment.hidden,
+          isFromCache: comment.isFromCache,
         );
 
   @override
@@ -53,6 +55,7 @@ class BuildableComment extends Comment with Buildable {
       hidden: hidden ?? this.hidden,
       level: level ?? this.level,
       elements: elements,
+      isFromCache: isFromCache,
     );
   }
 

lib/models/item/comment.dart

@@ -13,6 +13,7 @@ class Comment extends Item {
     required super.deleted,
     required super.hidden,
     required this.level,
+    required this.isFromCache,
   }) : super(
           descendants: 0,
           parts: <int>[],
@@ -21,9 +22,12 @@ class Comment extends Item {
           type: '',
         );
 
-  Comment.fromJson(super.json, {this.level = 0}) : super.fromJson();
+  Comment.fromJson(super.json, {this.level = 0})
+      : isFromCache = json['fromCache'] == true,
+        super.fromJson();
 
   final int level;
+  final bool isFromCache;
 
   String get metadata => '''by $by $timeAgo''';
 
@@ -45,6 +49,7 @@ class Comment extends Item {
       deleted: deleted,
       hidden: hidden ?? this.hidden,
       level: level ?? this.level,
+      isFromCache: isFromCache,
     );
   }
 

lib/models/item/item.dart

@@ -90,8 +90,13 @@ class Item extends Equatable {
   final List<int> kids;
   final List<int> parts;
 
-  String get timeAgo =>
-      DateTime.fromMillisecondsSinceEpoch(time * 1000).toTimeAgoString();
+  String get timeAgo {
+    int time = this.time;
+    if (time < 9999999999) {
+      time = time * 1000;
+    }
+    return DateTime.fromMillisecondsSinceEpoch(time).toTimeAgoString();
+  }
 
   bool get isPoll => type == 'poll';
 

lib/models/models.dart

@@ -1,4 +1,6 @@
+export 'app_exception.dart';
 export 'comments_order.dart';
+export 'discoverable_feature.dart';
 export 'export_destination.dart';
 export 'fetch_mode.dart';
 export 'font.dart';

lib/models/preference.dart

@@ -2,8 +2,10 @@ import 'dart:collection';
 import 'dart:io';
 
 import 'package:equatable/equatable.dart';
+import 'package:flutter_material_color_picker/flutter_material_color_picker.dart';
 import 'package:hacki/models/displayable.dart';
 import 'package:hacki/models/models.dart';
+import 'package:hacki/styles/palette.dart';
 
 abstract class Preference<T> extends Equatable with SettingsDisplayable {
   const Preference({required this.val});
@@ -24,19 +26,27 @@ abstract class Preference<T> extends Equatable with SettingsDisplayable {
       FontSizePreference(),
       TabOrderPreference(),
       StoryMarkingModePreference(),
+      AppColorPreference(),
+      const TextScaleFactorPreference(),
       // Order of items below matters and
       // reflects the order on settings screen.
       const DisplayModePreference(),
       const MetadataModePreference(),
       const StoryUrlModePreference(),
+      // Divider.
       const MarkReadStoriesModePreference(),
+      // Divider.
       const NotificationModePreference(),
-      const SwipeGesturePreference(),
       const AutoScrollModePreference(),
       const CollapseModePreference(),
       const ReaderModePreference(),
+      const CustomTabPreference(),
+      const ManualPaginationPreference(),
+      const SwipeGesturePreference(),
+      const HapticFeedbackPreference(),
       const EyeCandyModePreference(),
       const TrueDarkModePreference(),
+      const DevMode(),
     ],
   );
 
@@ -52,26 +62,57 @@ abstract class IntPreference extends Preference<int> {
   const IntPreference({required super.val});
 }
 
+abstract class DoublePreference extends Preference<double> {
+  const DoublePreference({required super.val});
+}
+
 const bool _notificationModeDefaultValue = true;
 const bool _swipeGestureModeDefaultValue = false;
 const bool _displayModeDefaultValue = true;
 const bool _eyeCandyModeDefaultValue = false;
-const bool _trueDarkModeDefaultValue = true;
+const bool _trueDarkModeDefaultValue = false;
+const bool _hapticFeedbackModeDefaultValue = true;
 const bool _readerModeDefaultValue = true;
 const bool _markReadStoriesModeDefaultValue = true;
 const bool _metadataModeDefaultValue = true;
 const bool _storyUrlModeDefaultValue = true;
 const bool _collapseModeDefaultValue = true;
-const bool _autoScrollModeDefaultValue = true;
+const bool _autoScrollModeDefaultValue = false;
+const bool _customTabModeDefaultValue = false;
+const bool _paginationModeDefaultValue = false;
+const bool _devModeDefaultValue = false;
+const double _textScaleFactorDefaultValue = 1;
 final int _fetchModeDefaultValue = FetchMode.eager.index;
 final int _commentsOrderDefaultValue = CommentsOrder.natural.index;
 final int _fontSizeDefaultValue = FontSize.regular.index;
-final int _fontDefaultValue = Font.roboto.index;
+final int _appColorDefaultValue = materialColors.indexOf(Palette.deepOrange);
+final int _fontDefaultValue = Font.robotoSlab.index;
 final int _tabOrderDefaultValue =
     StoryType.convertToSettingsValue(StoryType.values);
 final int _markStoriesAsReadWhenPreferenceDefaultValue =
     StoryMarkingMode.tap.index;
 
+class DevMode extends BooleanPreference {
+  const DevMode({bool? val}) : super(val: val ?? _devModeDefaultValue);
+
+  @override
+  DevMode copyWith({required bool? val}) {
+    return DevMode(val: val);
+  }
+
+  @override
+  String get key => 'devMode';
+
+  @override
+  String get title => 'Dev Mode';
+
+  @override
+  String get subtitle => '';
+
+  @override
+  bool get isDisplayable => false;
+}
+
 class SwipeGesturePreference extends BooleanPreference {
   const SwipeGesturePreference({bool? val})
       : super(val: val ?? _swipeGestureModeDefaultValue);
@@ -85,7 +126,7 @@ class SwipeGesturePreference extends BooleanPreference {
   String get key => 'swipeGestureMode';
 
   @override
-  String get title => 'Enable Swipe Gesture';
+  String get title => 'Swipe Gesture';
 
   @override
   String get subtitle =>
@@ -273,6 +314,52 @@ class EyeCandyModePreference extends BooleanPreference {
   String get subtitle => 'some sort of magic.';
 }
 
+class ManualPaginationPreference extends BooleanPreference {
+  const ManualPaginationPreference({bool? val})
+      : super(val: val ?? _paginationModeDefaultValue);
+
+  @override
+  ManualPaginationPreference copyWith({required bool? val}) {
+    return ManualPaginationPreference(val: val);
+  }
+
+  @override
+  String get key => 'paginationMode';
+
+  @override
+  String get title => 'Manual Pagination';
+
+  @override
+  String get subtitle => '''so you can get stuff done.''';
+}
+
+/// Whether or not to use Custom Tabs for launching URLs.
+/// If false, default browser will be used.
+///
+/// https://developer.chrome.com/docs/android/custom-tabs/
+class CustomTabPreference extends BooleanPreference {
+  const CustomTabPreference({bool? val})
+      : super(val: val ?? _customTabModeDefaultValue);
+
+  @override
+  CustomTabPreference copyWith({required bool? val}) {
+    return CustomTabPreference(val: val);
+  }
+
+  @override
+  String get key => 'customTabPreference';
+
+  @override
+  String get title => 'Use Custom Tabs';
+
+  @override
+  String get subtitle =>
+      '''use Custom tabs for URLs. If disabled, default browser is used instead.''';
+
+  @override
+  bool get isDisplayable => Platform.isAndroid;
+}
+
 class TrueDarkModePreference extends BooleanPreference {
   const TrueDarkModePreference({bool? val})
       : super(val: val ?? _trueDarkModeDefaultValue);
@@ -289,7 +376,26 @@ class TrueDarkModePreference extends BooleanPreference {
   String get title => 'True Dark Mode';
 
   @override
-  String get subtitle => 'you might need to restart the app.';
+  String get subtitle => 'real dark.';
+}
+
+class HapticFeedbackPreference extends BooleanPreference {
+  const HapticFeedbackPreference({bool? val})
+      : super(val: val ?? _hapticFeedbackModeDefaultValue);
+
+  @override
+  HapticFeedbackPreference copyWith({required bool? val}) {
+    return HapticFeedbackPreference(val: val);
+  }
+
+  @override
+  String get key => 'hapticFeedbackMode';
+
+  @override
+  String get title => 'Haptic Feedback';
+
+  @override
+  String get subtitle => '';
 }
 
 class FetchModePreference extends IntPreference {
@@ -381,5 +487,36 @@ class StoryMarkingModePreference extends IntPreference {
   String get key => 'storyMarkingMode';
 
   @override
-  String get title => 'Mark a Story as Read on';
+  String get title => 'Mark as Read on';
+}
+
+class AppColorPreference extends IntPreference {
+  AppColorPreference({int? val}) : super(val: val ?? _appColorDefaultValue);
+
+  @override
+  AppColorPreference copyWith({required int? val}) {
+    return AppColorPreference(val: val);
+  }
+
+  @override
+  String get key => 'appColor';
+
+  @override
+  String get title => 'Accent Color';
+}
+
+class TextScaleFactorPreference extends DoublePreference {
+  const TextScaleFactorPreference({double? val})
+      : super(val: val ?? _textScaleFactorDefaultValue);
+
+  @override
+  TextScaleFactorPreference copyWith({required double? val}) {
+    return TextScaleFactorPreference(val: val);
+  }
+
+  @override
+  String get key => 'appTextScaleFactor';
+
+  @override
+  String get title => 'Default text scale factor';
 }

lib/models/search_params.dart

@@ -8,31 +8,36 @@ class SearchParams extends Equatable {
     required this.filters,
     required this.query,
     required this.page,
-    this.sorted = false,
+    required this.sorted,
+    required this.exactMatch,
   });
 
   SearchParams.init()
       : filters = <SearchFilter>{},
         query = '',
         page = 0,
-        sorted = false;
+        sorted = false,
+        exactMatch = false;
 
   final Set<SearchFilter> filters;
   final String query;
   final int page;
   final bool sorted;
+  final bool exactMatch;
 
   SearchParams copyWith({
     Set<SearchFilter>? filters,
     String? query,
     int? page,
     bool? sorted,
+    bool? exactMatch,
   }) {
     return SearchParams(
       filters: filters ?? this.filters,
       query: query ?? this.query,
       page: page ?? this.page,
       sorted: sorted ?? this.sorted,
+      exactMatch: exactMatch ?? this.exactMatch,
     );
   }
 
@@ -43,6 +48,7 @@ class SearchParams extends Equatable {
       query: query,
       page: page,
       sorted: sorted,
+      exactMatch: exactMatch,
     );
   }
 
@@ -54,16 +60,19 @@ class SearchParams extends Equatable {
       query: query,
       page: page,
       sorted: sorted,
+      exactMatch: exactMatch,
     );
   }
 
   String get filteredQuery {
     final StringBuffer buffer = StringBuffer();
+    final String encodedQuery =
+        Uri.encodeComponent(exactMatch ? '"$query"' : query);
 
     if (sorted) {
-      buffer.write('search_by_date?query=${Uri.encodeComponent(query)}');
+      buffer.write('search_by_date?query=$encodedQuery');
     } else {
-      buffer.write('search?query=${Uri.encodeComponent(query)}');
+      buffer.write('search?query=$encodedQuery');
     }
 
     final Iterable<NumericFilter> numericFilters =
@@ -111,5 +120,6 @@ class SearchParams extends Equatable {
         query,
         page,
         sorted,
+        exactMatch,
       ];
 }

lib/models/story_marking_mode.dart

@@ -6,7 +6,8 @@ enum StoryMarkingMode {
   tap('tapping'),
   // Mark a story as read after user scrolls past or taps on it, whichever
   // happens the first.
-  scrollPastOrTap('scrolling past or tapping');
+  scrollPastOrTap('scrolling past or tapping'),
+  swipeGestureOnly('swipe gesture only');
 
   const StoryMarkingMode(this.label);