From 9a8561e45e9d06b8cf6b79bf2fb06854ec136a9b Mon Sep 17 00:00:00 2001
From: joschy2002 <joschygeiss@icloud.com>
Date: Wed, 25 Jun 2025 18:20:06 +0200
Subject: [PATCH] Commented Code

---
 trainerbox/lib/main.dart                      | 15 +++++-
 trainerbox/lib/models/exercise.dart           | 17 ++++--
 trainerbox/lib/screens/calendar_tab.dart      | 25 ++++++---
 trainerbox/lib/screens/favorites_tab.dart     | 11 ++--
 trainerbox/lib/screens/home_screen.dart       | 34 ++++++++----
 trainerbox/lib/screens/home_tab.dart          | 13 +++--
 trainerbox/lib/screens/login_screen.dart      | 43 +++++++++------
 trainerbox/lib/screens/profile_tab.dart       | 53 ++++++++++++++++---
 trainerbox/lib/screens/search_tab.dart        | 39 +++++++++++++-
 .../lib/screens/training_detail_screen.dart   | 30 ++++++++---
 trainerbox/lib/utils/responsive.dart          | 14 +++++
 trainerbox/lib/widgets/category_circle.dart   |  8 +++
 trainerbox/lib/widgets/exercise_card.dart     | 10 ++++
 13 files changed, 254 insertions(+), 58 deletions(-)

diff --git a/trainerbox/lib/main.dart b/trainerbox/lib/main.dart
index 9be86d5..97a7c76 100644
--- a/trainerbox/lib/main.dart
+++ b/trainerbox/lib/main.dart
@@ -1,5 +1,7 @@
 // main.dart
-// Einstiegspunkt der App und globale Konfigurationen
+// Entry point of the app and global configuration.
+// This file initializes Firebase, sets up localization, and launches the main app widget.
+
 import 'package:flutter/material.dart';
 import 'package:firebase_core/firebase_core.dart';
 import 'package:trainerbox/firebase_options.dart';
@@ -8,15 +10,21 @@ import 'screens/login_screen.dart';
 import 'screens/search_tab.dart';
 import 'package:intl/date_symbol_data_local.dart';
 
+/// Main entry point for the Flutter application.
 void main() async {
+  // Ensures that widget binding is initialized before using platform channels.
   WidgetsFlutterBinding.ensureInitialized();
+  // Initialize Firebase with platform-specific options.
   await Firebase.initializeApp(
     options: DefaultFirebaseOptions.currentPlatform,
   );
+  // Initialize date formatting for German locale.
   await initializeDateFormatting('de_DE', null);
+  // Start the app.
   runApp(const MyApp());
 }
 
+/// The root widget of the application.
 class MyApp extends StatefulWidget {
   const MyApp({super.key});
 
@@ -24,15 +32,18 @@ class MyApp extends StatefulWidget {
   State<MyApp> createState() => _MyAppState();
 }
 
+/// State for the main app widget, manages login state and routing.
 class _MyAppState extends State<MyApp> {
   bool _loggedIn = false;
 
+  /// Called when login is successful.
   void _handleLoginSuccess() {
     setState(() {
       _loggedIn = true;
     });
   }
 
+  /// Called when logout is successful.
   void _handleLogoutSuccess() {
     setState(() {
       _loggedIn = false;
@@ -48,9 +59,11 @@ class _MyAppState extends State<MyApp> {
         colorScheme: ColorScheme.fromSeed(seedColor: Colors.blue),
         useMaterial3: true,
       ),
+      // Show HomeScreen if logged in, otherwise show LoginScreen.
       home: _loggedIn
           ? HomeScreen(onLogoutSuccess: _handleLogoutSuccess)
           : LoginScreen(onLoginSuccess: _handleLoginSuccess),
+      // Define named routes for navigation.
       routes: {
         '/search': (context) => SearchTab(
           selectMode: (ModalRoute.of(context)?.settings.arguments as Map<String, dynamic>?)?['selectMode'] ?? false,
diff --git a/trainerbox/lib/models/exercise.dart b/trainerbox/lib/models/exercise.dart
index c2556a7..f0cc6c6 100644
--- a/trainerbox/lib/models/exercise.dart
+++ b/trainerbox/lib/models/exercise.dart
@@ -1,13 +1,24 @@
 // models/exercise.dart
+// Data model for a training exercise
 // Datenmodell für eine Trainingsübung
 
 import 'package:flutter/material.dart';
 
+/// Represents a training exercise with a title, category, and icon.
+/// Stellt eine Trainingsübung mit Titel, Kategorie und Icon dar.
 class Exercise {
-  final String title; // Name der Übung
-  final String category; // Kategorie der Übung
-  final IconData icon; // Icon zur Darstellung
+  /// The name/title of the exercise.
+  // Name der Übung
+  final String title;
+  /// The category of the exercise.
+  // Kategorie der Übung
+  final String category;
+  /// The icon used to visually represent the exercise.
+  // Icon zur Darstellung
+  final IconData icon;
 
+  /// Creates an Exercise instance.
+  /// Erstellt eine neue Instanz einer Übung.
   Exercise({
     required this.title,
     required this.category,
diff --git a/trainerbox/lib/screens/calendar_tab.dart b/trainerbox/lib/screens/calendar_tab.dart
index c04c911..659d45a 100644
--- a/trainerbox/lib/screens/calendar_tab.dart
+++ b/trainerbox/lib/screens/calendar_tab.dart
@@ -1,3 +1,6 @@
+// calendar_tab.dart
+// This file contains the CalendarTab widget, which displays a calendar view of trainings and allows users to view, add, and manage training events.
+
 import 'package:flutter/material.dart';
 import 'package:table_calendar/table_calendar.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
@@ -5,6 +8,7 @@ import 'package:firebase_auth/firebase_auth.dart';
 import 'training_detail_screen.dart';
 import 'package:uuid/uuid.dart';
 
+/// Mapping of training categories to colors for calendar display.
 const Map<String, Color> categoryColors = {
   'Aufwärmen & Mobilisation': Colors.deepOrange,
   'Wurf- & Torabschluss': Colors.orange,
@@ -14,6 +18,7 @@ const Map<String, Color> categoryColors = {
   'Koordination': Colors.teal,
 };
 
+/// The CalendarTab displays a calendar with all training events for the user.
 class CalendarTab extends StatefulWidget {
   final DateTime? initialDate;
   const CalendarTab({super.key, this.initialDate});
@@ -22,6 +27,7 @@ class CalendarTab extends StatefulWidget {
   State<CalendarTab> createState() => _CalendarTabState();
 }
 
+/// State for the CalendarTab, manages event loading, calendar state, and user interactions.
 class _CalendarTabState extends State<CalendarTab> {
   CalendarFormat _calendarFormat = CalendarFormat.week;
   late DateTime _focusedDay;
@@ -60,6 +66,7 @@ class _CalendarTabState extends State<CalendarTab> {
     }
   }
 
+  /// Initializes user data and loads events for the calendar.
   Future<void> _initializeData() async {
     if (_currentUserId != null) {
       final userDoc = await FirebaseFirestore.instance
@@ -76,6 +83,7 @@ class _CalendarTabState extends State<CalendarTab> {
     }
   }
 
+  /// Loads all training events for the current user (trainer or player).
   Future<void> _loadEvents() async {
     if (_userRole == null) return;
     
@@ -84,12 +92,14 @@ class _CalendarTabState extends State<CalendarTab> {
       QuerySnapshot trainersSnapshot;
       
       if (_userRole == 'trainer') {
+        // Trainer: only their own trainings
         trainersSnapshot = await FirebaseFirestore.instance
             .collection('User')
             .where('role', isEqualTo: 'trainer')
             .where(FieldPath.documentId, isEqualTo: _currentUserId)
             .get();
       } else {
+        // Player: trainings from trainers in their club
         final userDoc = await FirebaseFirestore.instance
             .collection('User')
             .doc(_currentUserId)
@@ -127,7 +137,7 @@ class _CalendarTabState extends State<CalendarTab> {
         final trainingTimes = trainerData['trainingTimes'] as Map<String, dynamic>? ?? {};
         final trainingDurations = trainerData['trainingDurations'] as Map<String, dynamic>? ?? {};
 
-        // Lade alle Trainings für das Datum
+        // Load all specific trainings for each date
         trainings.forEach((dateString, trainingsList) {
           final date = DateTime.tryParse(dateString);
           if (date == null) return;
@@ -144,6 +154,7 @@ class _CalendarTabState extends State<CalendarTab> {
               return sum;
             });
 
+            // Build the event map for this training
             final event = {
               'trainerName': trainerData['name'] ?? 'Unbekannter Trainer',
               'time': timeStr,
@@ -165,7 +176,7 @@ class _CalendarTabState extends State<CalendarTab> {
           }
         });
 
-        // Füge regelmäßige Trainings hinzu
+        // Add recurring weekly trainings for the year
         final now = DateTime.now();
         final yearStart = DateTime(now.year, 1, 1);
         final yearEnd = DateTime(now.year + 1, 1, 1);
@@ -179,7 +190,7 @@ class _CalendarTabState extends State<CalendarTab> {
           'Sonntag': 7,
         };
 
-        // Erstelle eine Set von gecancelten Daten für schnelleren Zugriff
+        // Create a set of cancelled dates for fast lookup
         final cancelledDates = cancelledTrainings
             .where((cancelled) => cancelled is Map<String, dynamic>)
             .map((cancelled) => DateTime.parse((cancelled as Map<String, dynamic>)['date'] as String))
@@ -195,23 +206,23 @@ class _CalendarTabState extends State<CalendarTab> {
           final duration = trainingDurations[day] ?? 60;
           final targetWeekday = weekdays[day] ?? 1;
 
-          // Finde das erste gewünschte Wochentags-Datum ab Jahresanfang
+          // Find the first desired weekday date from the start of the year
           DateTime firstDate = yearStart;
           while (firstDate.weekday != targetWeekday) {
             firstDate = firstDate.add(const Duration(days: 1));
           }
 
-          // Generiere Trainings für das gesamte Jahr
+          // Generate weekly trainings for the whole year
           while (firstDate.isBefore(yearEnd)) {
             final normalizedDate = DateTime(firstDate.year, firstDate.month, firstDate.day);
             final dateString = normalizedDate.toIso8601String();
             
-            // Prüfe, ob das Training für dieses Datum gecancelt ist
+            // Check if the training for this date is cancelled
             final isCancelled = cancelledDates.any((cancelledDate) => 
               isSameDay(cancelledDate, normalizedDate)
             );
 
-            // Prüfe, ob bereits ein spezifisches Training für dieses Datum existiert
+            // Check if a specific training already exists for this date
             final hasSpecificTraining = trainings.containsKey(dateString);
 
             if (!isCancelled && !hasSpecificTraining) {
diff --git a/trainerbox/lib/screens/favorites_tab.dart b/trainerbox/lib/screens/favorites_tab.dart
index 8e91bf8..d764d2c 100644
--- a/trainerbox/lib/screens/favorites_tab.dart
+++ b/trainerbox/lib/screens/favorites_tab.dart
@@ -1,8 +1,12 @@
+// favorites_tab.dart
+// This file contains the FavoritesTab widget, which displays the user's favorite exercises and allows filtering by category.
+
 import 'package:flutter/material.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 import 'training_detail_screen.dart';
 
+/// The FavoritesTab displays the user's favorite exercises and allows filtering by category.
 class FavoritesTab extends StatefulWidget {
   final String? categoryFilter;
   const FavoritesTab({super.key, this.categoryFilter});
@@ -11,6 +15,7 @@ class FavoritesTab extends StatefulWidget {
   State<FavoritesTab> createState() => _FavoritesTabState();
 }
 
+/// State for the FavoritesTab, manages category selection and favorite loading.
 class _FavoritesTabState extends State<FavoritesTab> {
   static const List<String> _categories = [
     'Aufwärmen & Mobilisation',
@@ -42,7 +47,7 @@ class _FavoritesTabState extends State<FavoritesTab> {
       body: Column(
         crossAxisAlignment: CrossAxisAlignment.center,
         children: [
-          // Filter-Chip-Leiste
+          // Category filter chips
           Padding(
             padding: const EdgeInsets.symmetric(vertical: 8),
             child: Wrap(
@@ -84,7 +89,7 @@ class _FavoritesTabState extends State<FavoritesTab> {
                   return const Center(child: Text('Keine Favoriten gefunden'));
                 }
 
-                // Lade alle Favoriten-Dokumente auf einmal
+                // Load all favorite exercise documents at once
                 return FutureBuilder<List<DocumentSnapshot>>(
                   future: Future.wait(allFavorites.map((id) =>
                     FirebaseFirestore.instance.collection('Training').doc(id).get()
@@ -97,7 +102,7 @@ class _FavoritesTabState extends State<FavoritesTab> {
                       return const Center(child: Text('Favoriten konnten nicht geladen werden'));
                     }
                     
-                    // Filtere die Favoriten basierend auf der Kategorie
+                    // Filter favorites by selected category
                     final filteredFavorites = multiSnapshot.data!.where((doc) {
                       if (!doc.exists) return false;
                       if (_selectedCategory == null) return true;
diff --git a/trainerbox/lib/screens/home_screen.dart b/trainerbox/lib/screens/home_screen.dart
index d8251b4..ca98618 100644
--- a/trainerbox/lib/screens/home_screen.dart
+++ b/trainerbox/lib/screens/home_screen.dart
@@ -1,5 +1,6 @@
 // screens/home_screen.dart
-// Enthält die BottomNavigationBar-Logik und Navigation zwischen den Hauptscreens
+// This file contains the main HomeScreen widget, which manages the bottom navigation bar and navigation between the main screens of the app.
+
 import 'package:flutter/material.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
@@ -10,6 +11,7 @@ import 'calendar_tab.dart';
 import 'profile_tab.dart';
 import 'training_detail_screen.dart';
 
+/// The main home screen of the app, containing the bottom navigation bar and all main tabs.
 class HomeScreen extends StatefulWidget {
   final VoidCallback? onLogoutSuccess;
   const HomeScreen({super.key, this.onLogoutSuccess});
@@ -18,6 +20,7 @@ class HomeScreen extends StatefulWidget {
   State<HomeScreen> createState() => _HomeScreenState();
 }
 
+/// State for the HomeScreen, manages navigation and data loading for the home tab.
 class _HomeScreenState extends State<HomeScreen> {
   int _selectedIndex = 0;
   Map<String, dynamic>? _nextTraining;
@@ -35,6 +38,7 @@ class _HomeScreenState extends State<HomeScreen> {
     _loadSuggestions();
   }
 
+  /// Loads exercise suggestions for the user based on unused and highly rated exercises.
   Future<void> _loadSuggestions() async {
     setState(() {
       _isLoadingSuggestions = true;
@@ -48,7 +52,7 @@ class _HomeScreenState extends State<HomeScreen> {
         return;
       }
 
-      // 1. Hole alle vom User genutzten Übungs-IDs
+      // 1. Get all exercise IDs used by the user
       final userDoc = await FirebaseFirestore.instance.collection('User').doc(user.uid).get();
       final Set<String> usedExerciseIds = {};
       if (userDoc.exists) {
@@ -67,14 +71,14 @@ class _HomeScreenState extends State<HomeScreen> {
         });
       }
 
-      // 2. Hole alle Übungen
+      // 2. Get all exercises
       final exercisesSnapshot = await FirebaseFirestore.instance.collection('Training').get();
 
       final allExercises = exercisesSnapshot.docs.map((doc) {
         return {'id': doc.id, ...doc.data() as Map<String, dynamic>};
       }).toList();
 
-      // 3. Filtere nach "nicht genutzt" und "gut bewertet"
+      // 3. Filter for unused and highly rated exercises
       final suggestions = allExercises.where((exercise) {
         final isUsed = usedExerciseIds.contains(exercise['id']);
         final rating = (exercise['rating overall'] as num?)?.toDouble() ?? 0.0;
@@ -91,11 +95,12 @@ class _HomeScreenState extends State<HomeScreen> {
     } catch (e) {
       setState(() {
         _isLoadingSuggestions = false;
-        _suggestionsError = 'Fehler beim Laden.';
+        _suggestionsError = 'Error loading suggestions.';
       });
     }
   }
 
+  /// Loads the next training event for the user, depending on their role and club.
   Future<void> _loadNextTraining() async {
     setState(() => _isLoading = true);
     try {
@@ -115,14 +120,14 @@ class _HomeScreenState extends State<HomeScreen> {
 
       QuerySnapshot trainersSnapshot;
       if (userRole == 'trainer') {
-        // Trainer sieht nur seine eigenen Trainings
+        // Trainer sees only their own trainings
         trainersSnapshot = await FirebaseFirestore.instance
             .collection('User')
             .where('role', isEqualTo: 'trainer')
             .where(FieldPath.documentId, isEqualTo: user.uid)
             .get();
       } else {
-        // Spieler sieht nur Trainings von Trainern seines Vereins
+        // Player sees only trainings from trainers in their club
         if (userClub == null || userClub.isEmpty) {
           setState(() {
             _nextTraining = null;
@@ -160,7 +165,7 @@ class _HomeScreenState extends State<HomeScreen> {
           final daysUntilNext = _getDaysUntilNext(day, now.weekday);
           final eventDate = DateTime(now.year, now.month, now.day + daysUntilNext, hour, minute);
 
-          // Prüfe die nächsten 4 Wochen
+          // Check the next 4 weeks
           for (var i = 0; i < 4; i++) {
             final date = eventDate.add(Duration(days: i * 7));
             final normalizedDate = DateTime(date.year, date.month, date.day);
@@ -180,7 +185,7 @@ class _HomeScreenState extends State<HomeScreen> {
                 'date': dateString,
                 'time': timeStr,
                 'duration': trainingDurations[day] ?? 60,
-                'trainerName': trainerData['name'] ?? 'Unbekannter Trainer',
+                'trainerName': trainerData['name'] ?? 'Unknown Trainer',
                 'day': day,
               };
             }
@@ -200,6 +205,7 @@ class _HomeScreenState extends State<HomeScreen> {
     }
   }
 
+  /// Returns the number of days until the next occurrence of a given weekday.
   int _getDaysUntilNext(String day, int currentWeekday) {
     final weekdays = {
       'Montag': 1,
@@ -219,22 +225,25 @@ class _HomeScreenState extends State<HomeScreen> {
     return daysUntilNext;
   }
 
+  /// Checks if two DateTime objects represent the same day.
   bool isSameDay(DateTime a, DateTime b) {
     return a.year == b.year && a.month == b.month && a.day == b.day;
   }
 
+  /// Handles navigation bar item taps and reloads suggestions if needed.
   void _onItemTapped(int index) {
     if (_selectedIndex != index) {
       setState(() {
         _selectedIndex = index;
       });
-      // Wenn zum Home-Tab gewechselt wird, lade die Vorschläge neu
+      // Reload suggestions when switching to the Home tab
       if (index == 0) {
         _loadSuggestions();
       }
     }
   }
 
+  /// List of main screens for the bottom navigation bar.
   List<Widget> get _screens => [
         _buildHomeTab(),
         const SearchTab(),
@@ -271,6 +280,7 @@ class _HomeScreenState extends State<HomeScreen> {
     );
   }
 
+  /// Builds the Home tab content, including next training, favorites, and suggestions.
   Widget _buildHomeTab() {
     return SafeArea(
       child: SingleChildScrollView(
@@ -440,6 +450,7 @@ class _HomeScreenState extends State<HomeScreen> {
     );
   }
 
+  /// Builds a favorite category circle with icon and label.
   Widget _buildFavoriteCircle(String label, IconData icon, Color color) {
     return Padding(
       padding: const EdgeInsets.only(right: 16.0),
@@ -474,6 +485,7 @@ class _HomeScreenState extends State<HomeScreen> {
     );
   }
 
+  /// Builds a suggestion card for an exercise.
   Widget _buildSuggestionCard(Map<String, dynamic> exercise) {
     final category = exercise['category'] as String? ?? 'Sonstiges';
     final title = exercise['title'] as String? ?? 'Unbekannte Übung';
@@ -553,6 +565,7 @@ class _HomeScreenState extends State<HomeScreen> {
   }
 }
 
+/// Mapping of category names to icons.
 const Map<String, IconData> categoryIcons = {
   'Aufwärmen & Mobilisation': Icons.directions_run,
   'Wurf- & Torabschluss': Icons.sports_handball,
@@ -562,6 +575,7 @@ const Map<String, IconData> categoryIcons = {
   'Koordination': Icons.directions_walk,
 };
 
+/// Mapping of category names to colors.
 const Map<String, Color> categoryColors = {
   'Aufwärmen & Mobilisation': Colors.deepOrange,
   'Wurf- & Torabschluss': Colors.orange,
diff --git a/trainerbox/lib/screens/home_tab.dart b/trainerbox/lib/screens/home_tab.dart
index 098700a..30403cb 100644
--- a/trainerbox/lib/screens/home_tab.dart
+++ b/trainerbox/lib/screens/home_tab.dart
@@ -1,7 +1,11 @@
+// home_tab.dart
+// This file contains the HomeTab widget, which displays a welcome message, a featured image, favorite categories, and exercise suggestions.
+
 import 'package:flutter/material.dart';
 import '../widgets/category_circle.dart';
 import '../widgets/exercise_card.dart';
 
+/// The HomeTab displays a welcome message, featured image, favorite categories, and exercise suggestions.
 class HomeTab extends StatelessWidget {
   const HomeTab({super.key});
 
@@ -13,7 +17,7 @@ class HomeTab extends StatelessWidget {
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.center,
           children: [
-            // Begrüßung
+            // Welcome message
             const Center(
               child: Text(
                 'Hallo Trainer!',
@@ -25,7 +29,7 @@ class HomeTab extends StatelessWidget {
               ),
             ),
             const SizedBox(height: 20),
-            // Bild mit Titel
+            // Featured image with title overlay
             Container(
               height: 200,
               width: double.infinity,
@@ -52,7 +56,7 @@ class HomeTab extends StatelessWidget {
               ),
             ),
             const SizedBox(height: 20),
-            // Favoriten Kategorien
+            // Favorite categories section
             const Text(
               'Favoriten',
               style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
@@ -77,7 +81,7 @@ class HomeTab extends StatelessWidget {
               ),
             ),
             const SizedBox(height: 20),
-            // Vorschläge
+            // Suggestions section
             const Text(
               'Vorschläge',
               style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
@@ -88,6 +92,7 @@ class HomeTab extends StatelessWidget {
               child: Stack(
                 alignment: Alignment.center,
                 children: [
+                  // PageView with exercise suggestion cards
                   PageView(
                     children: const [
                       ExerciseCard(
diff --git a/trainerbox/lib/screens/login_screen.dart b/trainerbox/lib/screens/login_screen.dart
index 228b137..c737e09 100644
--- a/trainerbox/lib/screens/login_screen.dart
+++ b/trainerbox/lib/screens/login_screen.dart
@@ -1,7 +1,11 @@
+// login_screen.dart
+// This file contains the LoginScreen widget, which handles user authentication (login and registration) and role selection.
+
 import 'package:flutter/material.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
 
+/// The LoginScreen allows users to log in or register, and select their role (trainer or player).
 class LoginScreen extends StatefulWidget {
   final void Function() onLoginSuccess;
   const LoginScreen({super.key, required this.onLoginSuccess});
@@ -10,6 +14,7 @@ class LoginScreen extends StatefulWidget {
   State<LoginScreen> createState() => _LoginScreenState();
 }
 
+/// State for the LoginScreen, manages form state, authentication, and error handling.
 class _LoginScreenState extends State<LoginScreen> {
   final _formKey = GlobalKey<FormState>();
   final _emailController = TextEditingController();
@@ -20,6 +25,7 @@ class _LoginScreenState extends State<LoginScreen> {
   bool _isLogin = true;
   bool _isTrainer = false;
 
+  /// Handles login or registration when the form is submitted.
   Future<void> _submit() async {
     setState(() { _loading = true; _error = null; });
     try {
@@ -31,31 +37,29 @@ class _LoginScreenState extends State<LoginScreen> {
             password: _passwordController.text.trim(),
           );
           
-          // Firestore-Check
+          // Check if user profile exists in Firestore
           final uid = cred.user!.uid;
-          
           final userDoc = await FirebaseFirestore.instance.collection('User').doc(uid).get();
           
           if (userDoc.exists) {
             widget.onLoginSuccess();
           } else {
-            setState(() { _error = 'Kein Benutzerprofil in der Datenbank gefunden!'; });
+            setState(() { _error = 'No user profile found in the database!'; });
             await FirebaseAuth.instance.signOut();
           }
         } catch (e) {
           rethrow;
         }
       } else {
-        // Registrierung
+        // Registration
         try {
           UserCredential cred = await FirebaseAuth.instance.createUserWithEmailAndPassword(
             email: _emailController.text.trim(),
             password: _passwordController.text.trim(),
           );
           
-          // User-Datensatz in Firestore anlegen
+          // Create user document in Firestore
           final uid = cred.user!.uid;
-          
           await FirebaseFirestore.instance.collection('User').doc(uid).set({
             'email': _emailController.text.trim(),
             'name': _nameController.text.trim(),
@@ -69,6 +73,7 @@ class _LoginScreenState extends State<LoginScreen> {
         }
       }
     } on FirebaseAuthException catch (e) {
+      // Handle Firebase authentication errors
       String errorMessage;
       switch (e.code) {
         case 'user-not-found':
@@ -81,7 +86,7 @@ class _LoginScreenState extends State<LoginScreen> {
           errorMessage = 'Ungültige E-Mail-Adresse.';
           break;
         case 'user-disabled':
-          errorMessage = 'Dieser Account wurde deaktiviert.';
+          errorMessage = 'Dieses Konto wurde deaktiviert.';
           break;
         case 'email-already-in-use':
           errorMessage = 'Diese E-Mail-Adresse wird bereits verwendet.';
@@ -90,14 +95,14 @@ class _LoginScreenState extends State<LoginScreen> {
           errorMessage = 'Das Passwort ist zu schwach.';
           break;
         case 'operation-not-allowed':
-          errorMessage = 'Diese Operation ist nicht erlaubt.';
+          errorMessage = 'Diese Aktion ist nicht erlaubt.';
           break;
         default:
           errorMessage = 'Ein Fehler ist aufgetreten: ${e.message}';
       }
       setState(() { _error = errorMessage; });
     } catch (e) {
-      setState(() { _error = 'Ein unerwarteter Fehler ist aufgetreten. Bitte versuchen Sie es später erneut.'; });
+      setState(() { _error = 'Ein unerwarteter Fehler ist aufgetreten. Bitte versuche es später erneut.'; });
     } finally {
       setState(() { _loading = false; });
     }
@@ -114,15 +119,18 @@ class _LoginScreenState extends State<LoginScreen> {
             child: Column(
               mainAxisSize: MainAxisSize.min,
               children: [
-                Text(_isLogin ? 'Login' : 'Registrieren', style: Theme.of(context).textTheme.headlineMedium),
+                // Title
+                Text(_isLogin ? 'Anmeldung' : 'Registrieren', style: Theme.of(context).textTheme.headlineMedium),
                 const SizedBox(height: 32),
                 if (!_isLogin) ...[
+                  // Name field for registration
                   TextFormField(
                     controller: _nameController,
                     decoration: const InputDecoration(labelText: 'Name'),
-                    validator: (v) => v != null && v.trim().isNotEmpty ? null : 'Name angeben',
+                    validator: (v) => v != null && v.trim().isNotEmpty ? null : 'Bitte gib deinen Namen ein',
                   ),
                   const SizedBox(height: 16),
+                  // Role selection
                   Row(
                     children: [
                       Checkbox(
@@ -144,24 +152,28 @@ class _LoginScreenState extends State<LoginScreen> {
                   ),
                   const SizedBox(height: 16),
                 ],
+                // Email field
                 TextFormField(
                   controller: _emailController,
                   decoration: const InputDecoration(labelText: 'E-Mail'),
                   keyboardType: TextInputType.emailAddress,
-                  validator: (v) => v != null && v.contains('@') ? null : 'Gib eine gültige E-Mail ein',
+                  validator: (v) => v != null && v.contains('@') ? null : 'Bitte gib eine gültige E-Mail ein',
                 ),
                 const SizedBox(height: 16),
+                // Password field
                 TextFormField(
                   controller: _passwordController,
                   decoration: const InputDecoration(labelText: 'Passwort'),
                   obscureText: true,
-                  validator: (v) => v != null && v.length >= 6 ? null : 'Mind. 6 Zeichen',
+                  validator: (v) => v != null && v.length >= 6 ? null : 'Mindestens 6 Zeichen',
                 ),
                 const SizedBox(height: 24),
                 if (_error != null) ...[
+                  // Error message
                   Text(_error!, style: const TextStyle(color: Colors.red)),
                   const SizedBox(height: 12),
                 ],
+                // Submit button
                 SizedBox(
                   width: double.infinity,
                   child: ElevatedButton(
@@ -174,10 +186,11 @@ class _LoginScreenState extends State<LoginScreen> {
                           },
                     child: _loading
                         ? const CircularProgressIndicator()
-                        : Text(_isLogin ? 'Login' : 'Registrieren'),
+                        : Text(_isLogin ? 'Anmelden' : 'Registrieren'),
                   ),
                 ),
                 const SizedBox(height: 16),
+                // Switch between login and registration
                 TextButton(
                   onPressed: _loading
                       ? null
@@ -187,7 +200,7 @@ class _LoginScreenState extends State<LoginScreen> {
                             _error = null;
                           });
                         },
-                  child: Text(_isLogin ? 'Noch keinen Account? Jetzt registrieren!' : 'Schon registriert? Jetzt einloggen!'),
+                  child: Text(_isLogin ? 'Noch kein Konto? Jetzt registrieren!' : 'Schon registriert? Jetzt anmelden!'),
                 ),
               ],
             ),
diff --git a/trainerbox/lib/screens/profile_tab.dart b/trainerbox/lib/screens/profile_tab.dart
index dbce400..40ac2ce 100644
--- a/trainerbox/lib/screens/profile_tab.dart
+++ b/trainerbox/lib/screens/profile_tab.dart
@@ -3,7 +3,12 @@ import 'package:firebase_auth/firebase_auth.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
 import 'package:intl/intl.dart';
 
+// profile_tab.dart
+// This file contains the ProfileTab widget, which allows users to view and edit their profile information, including training times and durations. Trainers have additional options for managing training schedules.
+
+/// The ProfileTab displays and allows editing of user profile information.
 class ProfileTab extends StatefulWidget {
+  /// Callback for when the user logs out successfully.
   final VoidCallback? onLogoutSuccess;
   const ProfileTab({super.key, this.onLogoutSuccess});
 
@@ -12,23 +17,35 @@ class ProfileTab extends StatefulWidget {
 }
 
 class _ProfileTabState extends State<ProfileTab> {
+  // Form key for validating the profile form.
   final _formKey = GlobalKey<FormState>();
+  // Indicates if the user is a trainer.
   bool _isTrainer = false;
+  // Indicates if data is currently loading.
   bool _isLoading = false;
+  // Stores training times for each day.
   Map<String, TimeOfDay?> _trainingTimes = {};
+  // Stores training durations for each day.
   Map<String, int> _trainingDurations = {};
+  // User's name.
   String _name = '';
+  // User's email.
   String _email = '';
+  // User's club.
   String _club = '';
+  // User's role (trainer or player).
   String? _userRole;
+  // Date the user joined.
   DateTime? _joinDate;
 
   @override
   void initState() {
     super.initState();
+    // Load user data when the widget is initialized.
     _loadUserData();
   }
 
+  /// Loads user data from Firebase and updates the state.
   Future<void> _loadUserData() async {
     final user = FirebaseAuth.instance.currentUser;
     if (user == null) return;
@@ -41,6 +58,7 @@ class _ProfileTabState extends State<ProfileTab> {
         final trainingTimes = data['trainingTimes'] as Map<String, dynamic>? ?? {};
         final trainingDurations = data['trainingDurations'] as Map<String, dynamic>? ?? {};
         
+        // Convert training times from string to TimeOfDay.
         final convertedTrainingTimes = <String, TimeOfDay?>{};
         trainingTimes.forEach((key, value) {
           if (value != null) {
@@ -79,6 +97,7 @@ class _ProfileTabState extends State<ProfileTab> {
     }
   }
 
+  /// Saves the training time and duration for a specific day to Firebase.
   Future<void> _saveTrainingTime(String day, TimeOfDay? time, int? duration) async {
     if (time == null || duration == null) return;
 
@@ -89,13 +108,13 @@ class _ProfileTabState extends State<ProfileTab> {
 
       final timeString = '${time.hour.toString().padLeft(2, '0')}:${time.minute.toString().padLeft(2, '0')}';
       
-      // Update training times and durations
+      // Update training times and durations in Firestore.
       await FirebaseFirestore.instance.collection('User').doc(user.uid).update({
         'trainingTimes.$day': timeString,
         'trainingDurations.$day': duration,
       });
 
-      // Trainings ab 1. Januar des aktuellen Jahres bis 52 Wochen in die Zukunft anlegen
+      // Create training entries from the start of the year for 52 weeks ahead.
       final now = DateTime.now();
       final yearStart = DateTime(now.year, 1, 1);
       final weekdays = {
@@ -109,7 +128,7 @@ class _ProfileTabState extends State<ProfileTab> {
       };
       final targetWeekday = weekdays[day] ?? 1;
 
-      // Finde das erste gewünschte Wochentags-Datum ab Jahresanfang
+      // Find the first occurrence of the target weekday from the start of the year.
       DateTime firstDate = yearStart;
       while (firstDate.weekday != targetWeekday) {
         firstDate = firstDate.add(const Duration(days: 1));
@@ -123,20 +142,20 @@ class _ProfileTabState extends State<ProfileTab> {
         newTrainingDates.add(dateString);
       }
 
-      // Load existing trainingExercises and cancelledTrainings
+      // Load existing trainingExercises and cancelledTrainings from Firestore.
       final userDoc = await FirebaseFirestore.instance.collection('User').doc(user.uid).get();
       final data = userDoc.data() ?? {};
       final trainingExercises = Map<String, dynamic>.from(data['trainingExercises'] ?? {});
       final cancelledTrainings = List<Map<String, dynamic>>.from(data['cancelledTrainings'] ?? []);
 
-      // Add empty training only if not already present
+      // Add empty training only if not already present.
       for (final dateString in newTrainingDates) {
         if (!trainingExercises.containsKey(dateString)) {
           trainingExercises[dateString] = [];
         }
       }
 
-      // Remove cancelledTrainings for these dates
+      // Remove cancelledTrainings for these dates.
       cancelledTrainings.removeWhere((cancelled) =>
         cancelled is Map<String, dynamic> &&
         cancelled.containsKey('date') &&
@@ -171,6 +190,7 @@ class _ProfileTabState extends State<ProfileTab> {
     }
   }
 
+  /// Removes the training time and duration for a specific day from Firebase.
   Future<void> _removeTrainingTime(String day) async {
     setState(() => _isLoading = true);
     try {
@@ -205,6 +225,7 @@ class _ProfileTabState extends State<ProfileTab> {
     }
   }
 
+  /// Opens a time picker dialog for selecting a training time, then a dialog for duration.
   Future<void> _selectTime(BuildContext context, String day) async {
     final TimeOfDay? picked = await showTimePicker(
       context: context,
@@ -223,6 +244,7 @@ class _ProfileTabState extends State<ProfileTab> {
     }
   }
 
+  /// Saves the user's profile data (name, club, training times, durations) to Firebase.
   Future<void> _saveUserData() async {
     if (FirebaseAuth.instance.currentUser == null) return;
 
@@ -268,6 +290,7 @@ class _ProfileTabState extends State<ProfileTab> {
   Widget build(BuildContext context) {
     final user = FirebaseAuth.instance.currentUser;
     if (user == null) {
+      // Show message if user is not logged in.
       return const Center(child: Text('Nicht eingeloggt'));
     }
 
@@ -278,6 +301,7 @@ class _ProfileTabState extends State<ProfileTab> {
           IconButton(
             icon: const Icon(Icons.logout),
             onPressed: () async {
+              // Log out the user and call the callback if provided.
               await FirebaseAuth.instance.signOut();
               if (widget.onLogoutSuccess != null) {
                 widget.onLogoutSuccess!();
@@ -297,6 +321,7 @@ class _ProfileTabState extends State<ProfileTab> {
               child: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
+                  // Card for personal information fields.
                   Card(
                     elevation: 4,
                     child: Padding(
@@ -312,6 +337,7 @@ class _ProfileTabState extends State<ProfileTab> {
                             ),
                           ),
                           const SizedBox(height: 16),
+                          // Editable name field.
                           TextField(
                             controller: TextEditingController(text: _name),
                             decoration: const InputDecoration(
@@ -322,6 +348,7 @@ class _ProfileTabState extends State<ProfileTab> {
                             onChanged: (value) => _name = value,
                           ),
                           const SizedBox(height: 16),
+                          // Non-editable email field.
                           TextField(
                             controller: TextEditingController(text: _email),
                             decoration: const InputDecoration(
@@ -332,6 +359,7 @@ class _ProfileTabState extends State<ProfileTab> {
                             enabled: false,
                           ),
                           const SizedBox(height: 16),
+                          // Editable club field.
                           TextField(
                             controller: TextEditingController(text: _club),
                             decoration: const InputDecoration(
@@ -343,7 +371,7 @@ class _ProfileTabState extends State<ProfileTab> {
                             onChanged: (value) => _club = value,
                           ),
                           const SizedBox(height: 16),
-                          // Rolle
+                          // Non-editable role field.
                           TextField(
                             controller: TextEditingController(text: _userRole == 'trainer' ? 'Trainer' : 'Spieler'),
                             decoration: const InputDecoration(
@@ -355,6 +383,7 @@ class _ProfileTabState extends State<ProfileTab> {
                           ),
                           if (_joinDate != null) ...[
                             const SizedBox(height: 16),
+                            // Non-editable join date field.
                             TextField(
                               controller: TextEditingController(text: DateFormat('dd.MM.yyyy').format(_joinDate!)),
                               decoration: const InputDecoration(
@@ -371,6 +400,7 @@ class _ProfileTabState extends State<ProfileTab> {
                   ),
                   if (_userRole == 'trainer') ...[
                     const SizedBox(height: 24),
+                    // Card for managing training times (visible only to trainers).
                     Card(
                       elevation: 4,
                       child: Padding(
@@ -386,6 +416,7 @@ class _ProfileTabState extends State<ProfileTab> {
                               ),
                             ),
                             const SizedBox(height: 16),
+                            // List of training days with time and duration controls.
                             ...['Montag', 'Dienstag', 'Mittwoch', 'Donnerstag', 'Freitag', 'Samstag', 'Sonntag']
                                 .map((day) => Card(
                                       margin: const EdgeInsets.only(bottom: 8),
@@ -400,6 +431,7 @@ class _ProfileTabState extends State<ProfileTab> {
                                         trailing: Row(
                                           mainAxisSize: MainAxisSize.min,
                                           children: [
+                                            // Edit or add training time button.
                                             IconButton(
                                               icon: Icon(
                                                 _trainingTimes[day] != null
@@ -411,6 +443,7 @@ class _ProfileTabState extends State<ProfileTab> {
                                                   : () => _selectTime(context, day),
                                             ),
                                             if (_trainingTimes[day] != null)
+                                              // Remove training time button.
                                               IconButton(
                                                 icon: const Icon(Icons.delete),
                                                 onPressed: _isLoading
@@ -434,6 +467,7 @@ class _ProfileTabState extends State<ProfileTab> {
   }
 }
 
+/// Dialog for selecting the duration of a training session.
 class _DurationDialog extends StatefulWidget {
   final int initialDuration;
 
@@ -449,6 +483,7 @@ class _DurationDialogState extends State<_DurationDialog> {
   @override
   void initState() {
     super.initState();
+    // Initialize duration with the provided initial value.
     _duration = widget.initialDuration;
   }
 
@@ -464,6 +499,7 @@ class _DurationDialogState extends State<_DurationDialog> {
           Row(
             mainAxisAlignment: MainAxisAlignment.center,
             children: [
+              // Decrement duration button (minimum 15 minutes).
               IconButton(
                 icon: const Icon(Icons.remove),
                 onPressed: () {
@@ -476,6 +512,7 @@ class _DurationDialogState extends State<_DurationDialog> {
                 '$_duration Minuten',
                 style: const TextStyle(fontSize: 18),
               ),
+              // Increment duration button (maximum 300 minutes).
               IconButton(
                 icon: const Icon(Icons.add),
                 onPressed: _duration < 300
@@ -487,10 +524,12 @@ class _DurationDialogState extends State<_DurationDialog> {
         ],
       ),
       actions: [
+        // Cancel button.
         TextButton(
           onPressed: () => Navigator.pop(context),
           child: const Text('Abbrechen'),
         ),
+        // Confirm button.
         ElevatedButton(
           onPressed: () => Navigator.pop(context, _duration),
           child: const Text('Bestätigen'),
diff --git a/trainerbox/lib/screens/search_tab.dart b/trainerbox/lib/screens/search_tab.dart
index 02a3f74..e365453 100644
--- a/trainerbox/lib/screens/search_tab.dart
+++ b/trainerbox/lib/screens/search_tab.dart
@@ -6,8 +6,11 @@ import 'package:image_picker/image_picker.dart';
 import 'dart:io';
 import 'training_detail_screen.dart';
 
+/// The SearchTab displays a searchable and filterable list of training exercises.
 class SearchTab extends StatefulWidget {
+  /// If true, enables selection mode for choosing exercises.
   final bool selectMode;
+  /// Remaining time for selection mode (optional).
   final int? remainingTime;
 
   const SearchTab({
@@ -21,7 +24,9 @@ class SearchTab extends StatefulWidget {
 }
 
 class _SearchTabState extends State<SearchTab> {
+  // Controller for the search input field.
   final TextEditingController _searchController = TextEditingController();
+  // List of available exercise categories.
   final List<String> _categories = [
     'Aufwärmen & Mobilisation',
     'Wurf- & Torabschluss',
@@ -30,15 +35,21 @@ class _SearchTabState extends State<SearchTab> {
     'Pass',
     'Koordination',
   ];
+  // Currently selected category for filtering.
   String? _selectedCategory;
+  // Current search term entered by the user.
   String _searchTerm = '';
+  // Indicates if the user is a trainer.
   bool _isTrainer = false;
+  // Indicates if the trainer check has completed.
   bool _trainerChecked = false;
+  // Set of favorite exercise IDs.
   Set<String> _favorites = {};
 
   @override
   void initState() {
     super.initState();
+    // Listen for changes in the search field and update the search term.
     _searchController.addListener(() {
       setState(() {
         _searchTerm = _searchController.text.trim();
@@ -48,6 +59,7 @@ class _SearchTabState extends State<SearchTab> {
     _loadFavorites();
   }
 
+  /// Checks if the current user is a trainer and updates state.
   Future<void> _checkIfTrainer() async {
     final user = FirebaseAuth.instance.currentUser;
     if (user == null) return;
@@ -58,6 +70,7 @@ class _SearchTabState extends State<SearchTab> {
     });
   }
 
+  /// Loads the user's favorite exercises from Firestore.
   Future<void> _loadFavorites() async {
     final user = FirebaseAuth.instance.currentUser;
     if (user == null) return;
@@ -70,13 +83,15 @@ class _SearchTabState extends State<SearchTab> {
     }
   }
 
+  /// Shows a dialog for creating a new training exercise (trainer only).
   void _showCreateTrainingDialog(BuildContext context) {
     showDialog(
       context: context,
       builder: (context) => _CreateTrainingDialog(categories: _categories),
-    ).then((_) => setState(() {})); // Refresh nach Hinzufügen
+    ).then((_) => setState(() {})); // Refresh after adding
   }
 
+  /// Toggles the favorite status of an exercise for the current user.
   Future<void> _toggleFavorite(String trainingId, bool isFavorite) async {
     final user = FirebaseAuth.instance.currentUser;
     if (user == null) return;
@@ -89,7 +104,7 @@ class _SearchTabState extends State<SearchTab> {
         'favorites': FieldValue.arrayUnion([trainingId]),
       });
     }
-    await _loadFavorites(); // Aktualisiere die Favoriten nach dem Toggle
+    await _loadFavorites(); // Update favorites after toggling
   }
 
   @override
@@ -112,6 +127,7 @@ class _SearchTabState extends State<SearchTab> {
       ),
       body: Column(
         children: [
+          // Search input field.
           Padding(
             padding: const EdgeInsets.all(8.0),
             child: TextField(
@@ -136,6 +152,7 @@ class _SearchTabState extends State<SearchTab> {
                 ),
               ),
             ),
+          // Category filter chips.
           Padding(
             padding: const EdgeInsets.all(16.0),
             child: Column(
@@ -164,6 +181,7 @@ class _SearchTabState extends State<SearchTab> {
               ],
             ),
           ),
+          // Exercise grid view.
           Expanded(
             child: FutureBuilder<QuerySnapshot>(
               future: FirebaseFirestore.instance.collection('Training').get(),
@@ -180,6 +198,7 @@ class _SearchTabState extends State<SearchTab> {
                   return const Center(child: Text('Keine Übungen gefunden'));
                 }
 
+                // Filter exercises by search term and category.
                 var exercises = snapshot.data!.docs.where((doc) {
                   final data = doc.data() as Map<String, dynamic>;
                   final title = data['title']?.toString().toLowerCase() ?? '';
@@ -210,6 +229,7 @@ class _SearchTabState extends State<SearchTab> {
                     final doc = exercises[index];
                     final data = doc.data() as Map<String, dynamic>;
                     final duration = (data['duration'] as num?)?.toInt() ?? 0;
+                    // Disable selection if duration exceeds remaining time in select mode.
                     final isDisabled = widget.selectMode && duration > (widget.remainingTime ?? 0);
 
                     return Card(
@@ -220,6 +240,7 @@ class _SearchTabState extends State<SearchTab> {
                                 ? null
                                 : () {
                                     if (widget.selectMode) {
+                                      // Return selected exercise data in select mode.
                                       Navigator.pop(context, {
                                         'id': doc.id,
                                         'title': data['title']?.toString() ?? 'Unbekannte Übung',
@@ -227,6 +248,7 @@ class _SearchTabState extends State<SearchTab> {
                                         'duration': duration,
                                       });
                                     } else {
+                                      // Navigate to exercise detail screen.
                                       Navigator.push(
                                         context,
                                         MaterialPageRoute(
@@ -293,6 +315,7 @@ class _SearchTabState extends State<SearchTab> {
                               ],
                             ),
                           ),
+                          // Favorite icon button (toggle favorite status).
                           Positioned(
                             top: 4,
                             right: 4,
@@ -324,6 +347,7 @@ class _SearchTabState extends State<SearchTab> {
   }
 }
 
+/// Dialog for creating a new training exercise.
 class _CreateTrainingDialog extends StatefulWidget {
   final List<String> categories;
   const _CreateTrainingDialog({required this.categories});
@@ -333,16 +357,26 @@ class _CreateTrainingDialog extends StatefulWidget {
 }
 
 class _CreateTrainingDialogState extends State<_CreateTrainingDialog> {
+  // Form key for validating the create training form.
   final _formKey = GlobalKey<FormState>();
+  // Selected category for the new training.
   String? _category;
+  // Title of the new training.
   String? _title;
+  // Description of the new training.
   String? _description;
+  // Duration of the new training.
   int? _duration;
+  // Difficulty level or year.
   String? _year;
+  // Indicates if the dialog is loading (creating training).
   bool _loading = false;
+  // Selected image file for the training.
   File? _imageFile;
+  // Image picker instance.
   final _picker = ImagePicker();
 
+  /// Opens the image picker to select an image from the gallery.
   Future<void> _pickImage() async {
     final pickedFile = await _picker.pickImage(source: ImageSource.gallery);
     if (pickedFile != null) {
@@ -352,6 +386,7 @@ class _CreateTrainingDialogState extends State<_CreateTrainingDialog> {
     }
   }
 
+  /// Uploads the selected image to Firebase Storage and returns the download URL.
   Future<String?> _uploadImage() async {
     if (_imageFile == null) return null;
     
diff --git a/trainerbox/lib/screens/training_detail_screen.dart b/trainerbox/lib/screens/training_detail_screen.dart
index cfd559f..5a0de2b 100644
--- a/trainerbox/lib/screens/training_detail_screen.dart
+++ b/trainerbox/lib/screens/training_detail_screen.dart
@@ -2,7 +2,9 @@ import 'package:flutter/material.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 
+/// The TrainingDetailScreen displays details and ratings for a specific training exercise.
 class TrainingDetailScreen extends StatefulWidget {
+  /// The ID of the training exercise to display.
   final String trainingId;
 
   const TrainingDetailScreen({super.key, required this.trainingId});
@@ -12,17 +14,23 @@ class TrainingDetailScreen extends StatefulWidget {
 }
 
 class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
+  // The current user's rating for this exercise.
   double? _userRating;
+  // Indicates if a loading operation is in progress.
   bool _isLoading = false;
+  // Indicates if the current user is a player (not a trainer).
   bool _isPlayer = false;
+  // Indicates if the user role check has completed.
   bool _userRoleChecked = false;
 
   @override
   void initState() {
     super.initState();
+    // Check the user's role when the widget is initialized.
     _checkUserRole();
   }
 
+  /// Checks the current user's role (player or trainer) and updates state.
   Future<void> _checkUserRole() async {
     final user = FirebaseAuth.instance.currentUser;
     if (user == null) return;
@@ -40,6 +48,7 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
     }
   }
 
+  /// Submits a rating for the current training exercise by the user.
   Future<void> _submitRating(double rating) async {
     if (!_isPlayer) {
       ScaffoldMessenger.of(context).showSnackBar(
@@ -65,23 +74,23 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
       final data = trainingDoc.data() as Map<String, dynamic>;
       List<dynamic> ratings = List<dynamic>.from(data['ratings'] ?? []);
       
-      // Entferne alte Bewertung des Users falls vorhanden
+      // Remove old rating from this user if present.
       ratings.removeWhere((r) => r['userId'] == user.uid);
       
-      // Füge neue Bewertung hinzu
+      // Add new rating.
       ratings.add({
         'userId': user.uid,
         'rating': rating,
-        'timestamp': DateTime.now().toIso8601String(), // Verwende ISO-String statt FieldValue
+        'timestamp': DateTime.now().toIso8601String(), // Use ISO string for timestamp
       });
 
-      // Berechne neue Gesamtbewertung
+      // Calculate new overall rating.
       double overallRating = 0;
       if (ratings.isNotEmpty) {
         overallRating = ratings.map((r) => (r['rating'] as num).toDouble()).reduce((a, b) => a + b) / ratings.length;
       }
 
-      // Aktualisiere das Dokument
+      // Update the training document with new ratings and overall rating.
       await trainingRef.update({
         'ratings': ratings,
         'rating overall': overallRating,
@@ -123,7 +132,7 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
           }
           final data = snapshot.data!.data() as Map<String, dynamic>;
           
-          // Hole die Bewertung des aktuellen Users
+          // Get the current user's rating for this exercise if not already loaded.
           final user = FirebaseAuth.instance.currentUser;
           if (user != null && _userRating == null) {
             final ratings = List<dynamic>.from(data['ratings'] ?? []);
@@ -141,6 +150,7 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
             child: Column(
               crossAxisAlignment: CrossAxisAlignment.start,
               children: [
+                // Display the exercise image if available.
                 Container(
                   width: double.infinity,
                   height: 200,
@@ -155,6 +165,7 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
                         ),
                 ),
                 const SizedBox(height: 16),
+                // Display the exercise title.
                 Text(
                   data['title'] ?? 'Unbekannt',
                   style: const TextStyle(
@@ -163,21 +174,25 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
                   ),
                 ),
                 const SizedBox(height: 8),
+                // Display the exercise description.
                 Text(
                   data['description'] ?? 'Keine Beschreibung',
                   style: TextStyle(color: Colors.grey[600]),
                 ),
                 const SizedBox(height: 16),
+                // Display the exercise duration.
                 Text(
                   'Dauer: ${data['duration'] ?? '-'} Minuten',
                   style: TextStyle(color: Colors.grey[600]),
                 ),
                 const SizedBox(height: 8),
+                // Display the exercise level/year.
                 Text(
                   'Level: ${data['year'] ?? '-'}',
                   style: TextStyle(color: Colors.grey[600]),
                 ),
                 const SizedBox(height: 16),
+                // Display the average rating.
                 Row(
                   children: [
                     const Icon(Icons.star, color: Colors.amber),
@@ -189,10 +204,12 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
                   ],
                 ),
                 const SizedBox(height: 8),
+                // Display the number of ratings.
                 Text(
                   'Anzahl Bewertungen: ${(data['ratings'] ?? []).length}',
                   style: TextStyle(color: Colors.grey[600]),
                 ),
+                // Show rating controls if the user is a player.
                 if (_userRoleChecked && _isPlayer) ...[
                   const SizedBox(height: 16),
                   const Text(
@@ -222,6 +239,7 @@ class _TrainingDetailScreenState extends State<TrainingDetailScreen> {
                     ),
                 ],
                 const SizedBox(height: 8),
+                // Display the exercise category.
                 Text(
                   'Kategorie: ${data['category'] ?? '-'}',
                   style: TextStyle(color: Colors.grey[600]),
diff --git a/trainerbox/lib/utils/responsive.dart b/trainerbox/lib/utils/responsive.dart
index 4f86a5b..a69bb77 100644
--- a/trainerbox/lib/utils/responsive.dart
+++ b/trainerbox/lib/utils/responsive.dart
@@ -1,28 +1,40 @@
+// responsive.dart
+// Utility class for handling responsive design in Flutter apps. Provides helpers for device type checks, scaling, and adaptive sizing.
+
 import 'package:flutter/material.dart';
 
+/// The Responsive class provides static methods to help adapt UI to different screen sizes (mobile, tablet, desktop).
 class Responsive {
+  /// Returns true if the device is considered a mobile (width < 600px).
   static bool isMobile(BuildContext context) =>
       MediaQuery.of(context).size.width < 600;
 
+  /// Returns true if the device is considered a tablet (600px <= width < 1200px).
   static bool isTablet(BuildContext context) =>
       MediaQuery.of(context).size.width >= 600 &&
       MediaQuery.of(context).size.width < 1200;
 
+  /// Returns true if the device is considered a desktop (width >= 1200px).
   static bool isDesktop(BuildContext context) =>
       MediaQuery.of(context).size.width >= 1200;
 
+  /// Returns the current screen width in logical pixels.
   static double getWidth(BuildContext context) =>
       MediaQuery.of(context).size.width;
 
+  /// Returns the current screen height in logical pixels.
   static double getHeight(BuildContext context) =>
       MediaQuery.of(context).size.height;
 
+  /// Returns a width scaled by the given percentage of the screen width.
   static double getScaledWidth(BuildContext context, double percentage) =>
       getWidth(context) * (percentage / 100);
 
+  /// Returns a height scaled by the given percentage of the screen height.
   static double getScaledHeight(BuildContext context, double percentage) =>
       getHeight(context) * (percentage / 100);
 
+  /// Returns appropriate padding based on device type (mobile/tablet/desktop).
   static EdgeInsets getPadding(BuildContext context) {
     if (isMobile(context)) {
       return const EdgeInsets.all(16.0);
@@ -33,6 +45,7 @@ class Responsive {
     }
   }
 
+  /// Returns a font size scaled for the device type.
   static double getFontSize(BuildContext context, double baseSize) {
     if (isMobile(context)) {
       return baseSize;
@@ -43,6 +56,7 @@ class Responsive {
     }
   }
 
+  /// Returns an icon size scaled for the device type.
   static double getIconSize(BuildContext context, double baseSize) {
     if (isMobile(context)) {
       return baseSize;
diff --git a/trainerbox/lib/widgets/category_circle.dart b/trainerbox/lib/widgets/category_circle.dart
index 9e7b56f..8294c3e 100644
--- a/trainerbox/lib/widgets/category_circle.dart
+++ b/trainerbox/lib/widgets/category_circle.dart
@@ -1,11 +1,17 @@
 // widgets/category_circle.dart
+// Widget for a circular category view
 // Widget für eine runde Kategorie-Ansicht
 import 'package:flutter/material.dart';
 
+/// A widget that displays a category as a circle with an icon and a title below.
+/// Widget, das eine Kategorie als Kreis mit Icon und Titel darunter darstellt.
 class CategoryCircle extends StatelessWidget {
+  /// The title of the category.
   final String title;
+  /// The icon representing the category.
   final IconData icon;
 
+  /// Creates a CategoryCircle widget.
   const CategoryCircle({super.key, required this.title, required this.icon});
 
   @override
@@ -14,6 +20,7 @@ class CategoryCircle extends StatelessWidget {
       padding: const EdgeInsets.only(right: 16.0),
       child: Column(
         children: [
+          // Circle with icon
           // Kreis mit Icon
           Container(
             width: 70,
@@ -29,6 +36,7 @@ class CategoryCircle extends StatelessWidget {
             ),
           ),
           const SizedBox(height: 8),
+          // Title below the circle
           // Titel unter dem Kreis
           Text(
             title,
diff --git a/trainerbox/lib/widgets/exercise_card.dart b/trainerbox/lib/widgets/exercise_card.dart
index 2628c8b..5267d8c 100644
--- a/trainerbox/lib/widgets/exercise_card.dart
+++ b/trainerbox/lib/widgets/exercise_card.dart
@@ -1,12 +1,19 @@
 // widgets/exercise_card.dart
+// Widget for a training exercise card view
 // Widget für eine Trainingskarten-Ansicht
 import 'package:flutter/material.dart';
 
+/// A widget that displays a card for a training exercise, showing its icon, title, and category.
+/// Widget, das eine Karte für eine Trainingsübung mit Icon, Titel und Kategorie anzeigt.
 class ExerciseCard extends StatelessWidget {
+  /// The title of the exercise.
   final String title;
+  /// The category of the exercise.
   final String category;
+  /// The icon representing the exercise.
   final IconData icon;
 
+  /// Creates an ExerciseCard widget.
   const ExerciseCard({
     super.key,
     required this.title,
@@ -26,9 +33,11 @@ class ExerciseCard extends StatelessWidget {
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
+            // Icon for the exercise
             // Icon für die Übung
             Icon(icon, size: 60, color: Theme.of(context).colorScheme.primary),
             const SizedBox(height: 16),
+            // Title of the exercise
             // Titel der Übung
             Text(
               title,
@@ -36,6 +45,7 @@ class ExerciseCard extends StatelessWidget {
               textAlign: TextAlign.center,
             ),
             const SizedBox(height: 8),
+            // Category badge
             // Kategorie-Badge
             Container(
               padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 4),