refactor: Remove flutter_app_lock package and use own AppLock implementation

lib/widgets/app_lock.dart

@@ -0,0 +1,88 @@
+import 'package:flutter/material.dart';
+
+import 'package:flutter_secure_storage/flutter_secure_storage.dart';
+import 'package:provider/provider.dart';
+
+import 'package:fluffychat/config/setting_keys.dart';
+import 'package:fluffychat/config/themes.dart';
+import 'package:fluffychat/widgets/lock_screen.dart';
+
+class AppLockWidget extends StatefulWidget {
+  const AppLockWidget({
+    required this.child,
+    required this.pincode,
+    super.key,
+  });
+
+  final String? pincode;
+  final Widget child;
+
+  @override
+  State<AppLockWidget> createState() => AppLock();
+}
+
+class AppLock extends State<AppLockWidget> with WidgetsBindingObserver {
+  String? _pincode;
+  bool _isLocked = false;
+  bool get isActive => _pincode != null;
+
+  @override
+  void initState() {
+    _pincode = widget.pincode;
+    _isLocked = widget.pincode != null;
+    super.initState();
+    WidgetsBinding.instance.addObserver(this);
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    if (isActive && state == AppLifecycleState.hidden && !_isLocked) {
+      setState(() {
+        _isLocked = true;
+      });
+    }
+  }
+
+  bool get isLocked => _isLocked;
+  CrossFadeState get _crossFadeState =>
+      _isLocked ? CrossFadeState.showSecond : CrossFadeState.showFirst;
+
+  Future<void> changePincode(String? pincode) async {
+    await const FlutterSecureStorage().write(
+      key: SettingKeys.appLockKey,
+      value: pincode,
+    );
+    _pincode = pincode;
+    return;
+  }
+
+  bool unlock(String pincode) {
+    final isCorrect = pincode == _pincode;
+    if (isCorrect) {
+      setState(() {
+        _isLocked = false;
+      });
+    }
+    return isCorrect;
+  }
+
+  void showLockScreen() => setState(() {
+        _isLocked = true;
+      });
+
+  static AppLock of(BuildContext context) => Provider.of<AppLock>(
+        context,
+        listen: false,
+      );
+
+  @override
+  Widget build(BuildContext context) => Provider<AppLock>(
+        create: (_) => this,
+        child: AnimatedCrossFade(
+          firstChild: widget.child,
+          secondChild: const LockScreen(),
+          crossFadeState: _crossFadeState,
+          duration: FluffyThemes.animationDuration,
+        ),
+      );
+}

lib/widgets/fluffy_chat_app.dart

@@ -6,6 +6,7 @@ import 'package:matrix/matrix.dart';
 
 import 'package:fluffychat/config/routes.dart';
 import 'package:fluffychat/config/themes.dart';
+import 'package:fluffychat/widgets/app_lock.dart';
 import 'package:fluffychat/widgets/theme_builder.dart';
 import '../config/app_config.dart';
 import '../utils/custom_scroll_behaviour.dart';
@@ -14,11 +15,13 @@ import 'matrix.dart';
 class FluffyChatApp extends StatelessWidget {
   final Widget? testWidget;
   final List<Client> clients;
+  final String? pincode;
 
   const FluffyChatApp({
     Key? key,
     this.testWidget,
     required this.clients,
+    this.pincode,
   }) : super(key: key);
 
   /// getInitialLink may rereturn the value multiple times if this view is
@@ -43,12 +46,11 @@ class FluffyChatApp extends StatelessWidget {
         localizationsDelegates: L10n.localizationsDelegates,
         supportedLocales: L10n.supportedLocales,
         routerConfig: router,
-        builder: (context, child) => Navigator(
-          onGenerateRoute: (_) => MaterialPageRoute(
-            builder: (_) => Matrix(
-              clients: clients,
-              child: testWidget ?? child,
-            ),
+        builder: (context, child) => AppLockWidget(
+          pincode: pincode,
+          child: Matrix(
+            clients: clients,
+            child: testWidget ?? child,
           ),
         ),
       ),

lib/widgets/lock_screen.dart

@@ -2,14 +2,11 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 
-import 'package:flutter_app_lock/flutter_app_lock.dart';
 import 'package:flutter_gen/gen_l10n/l10n.dart';
-import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 
 import 'package:fluffychat/config/app_config.dart';
-import 'package:fluffychat/config/setting_keys.dart';
 import 'package:fluffychat/config/themes.dart';
-import 'package:fluffychat/utils/error_reporter.dart';
+import 'package:fluffychat/widgets/app_lock.dart';
 import 'package:fluffychat/widgets/theme_builder.dart';
 
 class LockScreen extends StatefulWidget {
@@ -40,25 +37,15 @@ class _LockScreenState extends State<LockScreen> {
       return;
     }
 
-    final correctPin = int.tryParse(
-      await const FlutterSecureStorage().read(key: SettingKeys.appLockKey) ??
-          '',
-    );
-    if (correctPin == null) {
-      ErrorReporter(
-        context,
-        'Lockscreen was displayed but pin was not stored correctly',
-      ).onErrorCallback(
-        Exception(),
-      );
-      AppLock.of(context)!.didUnlock();
+    if (AppLock.of(context).unlock(enteredPin.toString())) {
+      setState(() {
+        _inputBlocked = false;
+        _errorText = null;
+      });
+      _textEditingController.clear();
       return;
     }
 
-    if (correctPin == enteredPin) {
-      AppLock.of(context)!.didUnlock();
-      return;
-    }
     setState(() {
       _errorText = L10n.of(context)!.wrongPinEntered(_coolDownSeconds);
       _inputBlocked = true;
@@ -102,12 +89,10 @@ class _LockScreenState extends State<LockScreen> {
                     shrinkWrap: true,
                     children: [
                       Center(
-                        child: _inputBlocked
-                            ? const CircularProgressIndicator.adaptive()
-                            : Image.asset(
-                                'assets/info-logo.png',
-                                width: 256,
-                              ),
+                        child: Image.asset(
+                          'assets/info-logo.png',
+                          width: 256,
+                        ),
                       ),
                       TextField(
                         controller: _textEditingController,
@@ -125,6 +110,11 @@ class _LockScreenState extends State<LockScreen> {
                           hintText: '****',
                         ),
                       ),
+                      if (_inputBlocked)
+                        const Padding(
+                          padding: EdgeInsets.all(8.0),
+                          child: LinearProgressIndicator(),
+                        ),
                     ],
                   ),
                 ),