Refactor screens logic

lib/flashcard_screen.dart

@@ -0,0 +1,204 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'vocabulary.dart';
+
+class FlashcardScreen extends StatefulWidget {
+  final Vocabulary vocabulary;
+  final int count;
+  const FlashcardScreen({
+    super.key,
+    required this.vocabulary,
+    required this.count,
+  });
+
+  @override
+  State<FlashcardScreen> createState() => _FlashcardScreenState();
+}
+
+class _FlashcardScreenState extends State<FlashcardScreen> {
+  late List<Entry> _quizEntries;
+  int _current = 0;
+  int _correct = 0;
+  int _incorrect = 0;
+  String? _feedback;
+  final _controller = TextEditingController();
+  bool _showingFeedback = false;
+  final FocusNode _inputFocusNode = FocusNode();
+  final FocusNode _keyboardFocusNode = FocusNode();
+
+  @override
+  void initState() {
+    super.initState();
+    _quizEntries = List<Entry>.from(widget.vocabulary.entries);
+    _quizEntries.shuffle();
+    if (_quizEntries.length > widget.count) {
+      _quizEntries = _quizEntries.sublist(0, widget.count);
+    }
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    _inputFocusNode.dispose();
+    _keyboardFocusNode.dispose();
+    super.dispose();
+  }
+
+  void _requestInputFocus() {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (!_showingFeedback) {
+        _inputFocusNode.requestFocus();
+      }
+    });
+  }
+
+  void _requestKeyboardFocus() {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (_showingFeedback) {
+        _keyboardFocusNode.requestFocus();
+      }
+    });
+  }
+
+  void _submit() {
+    if (_showingFeedback) {
+      setState(() {
+        _feedback = null;
+        _showingFeedback = false;
+        _controller.clear();
+        _current++;
+      });
+      _requestInputFocus();
+      return;
+    }
+    final userInput = _controller.text.trim().toLowerCase();
+    final correctAnswer = _quizEntries[_current].target.trim().toLowerCase();
+    if (userInput == correctAnswer) {
+      setState(() {
+        _correct++;
+        _feedback = 'Correct!\nThe ${widget.vocabulary.targetLanguage} translation is: ${_quizEntries[_current].target}';
+        _showingFeedback = true;
+      });
+      _requestKeyboardFocus();
+    } else {
+      setState(() {
+        _incorrect++;
+        _feedback = 'Incorrect.\nThe correct ${widget.vocabulary.targetLanguage} translation is: ${_quizEntries[_current].target}';
+        _showingFeedback = true;
+      });
+      _requestKeyboardFocus();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if (_current >= _quizEntries.length) {
+      int total = _correct + _incorrect;
+      double percent = total > 0 ? (_correct / total) * 100 : 0;
+      return Scaffold(
+        appBar: AppBar(title: const Text('Flashcards')),
+        body: Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              Text('Quiz complete!', style: Theme.of(context).textTheme.headlineSmall),
+              const SizedBox(height: 16),
+              Text('Correct:  $_correct', style: const TextStyle(color: Colors.green, fontSize: 18)),
+              Text('Incorrect:  $_incorrect', style: const TextStyle(color: Colors.red, fontSize: 18)),
+              const SizedBox(height: 8),
+              Text('Total score: ${percent.toStringAsFixed(1)}%', style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 20)),
+              const SizedBox(height: 24),
+              ElevatedButton(
+                onPressed: () => Navigator.pop(context),
+                child: const Text('Back to practice'),
+              ),
+            ],
+          ),
+        ),
+      );
+    }
+    final entry = _quizEntries[_current];
+    if (!_showingFeedback) {
+      _requestInputFocus();
+    } else {
+      _requestKeyboardFocus();
+    }
+    return Scaffold(
+      appBar: AppBar(title: const Text('Flashcards')),
+      body: Padding(
+        padding: const EdgeInsets.all(24.0),
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            Text('${widget.vocabulary.sourceLanguage}:', style: Theme.of(context).textTheme.titleLarge),
+            const SizedBox(height: 8),
+            Text(
+              entry.source,
+              style: Theme.of(context).textTheme.headlineMedium,
+              textDirection: widget.vocabulary.sourceReadingDirection,
+            ),
+            const SizedBox(height: 32),
+            RawKeyboardListener(
+              focusNode: _keyboardFocusNode,
+              autofocus: true,
+              onKey: (event) {
+                if (_showingFeedback && event.isKeyPressed(LogicalKeyboardKey.enter) && event.runtimeType.toString() == 'RawKeyDownEvent') {
+                  setState(() {
+                    _feedback = null;
+                    _showingFeedback = false;
+                    _controller.clear();
+                    _current++;
+                  });
+                  _requestInputFocus();
+                }
+              },
+              child: Column(
+                children: [
+                  if (_feedback == null) ...[
+                    TextField(
+                      controller: _controller,
+                      focusNode: _inputFocusNode,
+                      decoration: InputDecoration(
+                        labelText: '${widget.vocabulary.targetLanguage} translation',
+                        border: const OutlineInputBorder(),
+                      ),
+                      onSubmitted: (_) => _submit(),
+                      enabled: !_showingFeedback,
+                    ),
+                    const SizedBox(height: 16),
+                    ElevatedButton(
+                      onPressed: _submit,
+                      child: const Text('Submit'),
+                    ),
+                  ] else ...[
+                    Text(
+                      _feedback!,
+                      style: TextStyle(fontSize: 20, color: _feedback!.startsWith('Correct!') ? Colors.green : Colors.red),
+                      softWrap: true,
+                      maxLines: null,
+                    ),
+                    const SizedBox(height: 16),
+                    ElevatedButton(
+                      onPressed: () {
+                        setState(() {
+                          _feedback = null;
+                          _showingFeedback = false;
+                          _controller.clear();
+                          _current++;
+                        });
+                        _requestInputFocus();
+                      },
+                      child: const Text('Next'),
+                    ),
+                  ],
+                ],
+              ),
+            ),
+            const SizedBox(height: 32),
+            Text('Progress: ${_current + 1} / ${_quizEntries.length}'),
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/main.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
-import 'screens.dart';
+import 'practice_screen.dart';
+import 'vocabulary_screen.dart';
 
 void main() {
   runApp(const LexikonApp());
@@ -75,7 +76,7 @@ class WelcomeScreen extends StatelessWidget {
     return const Scaffold(
       body: Center(
         child: Text(
-          'Welcome to Lexikon!',
+          'Welcome to LexiKon!',
           style: TextStyle(fontSize: 28, fontWeight: FontWeight.bold),
         ),
       ),