GermanApp/Application/DTOs/LevelDto.cs

@@ -1,51 +0,0 @@
-using GermanApp.Domain.Entities;
-
-namespace GermanApp.Application.DTOs;
-
-/// <summary>
-/// Data Transfer Object for Level - used for API responses.
-/// This is a read-only representation of a Level entity.
-/// </summary>
-public record LevelDto(
-    int Id,
-    string Name,
-    string Code,
-    int Order);
-
-/// <summary>
-/// Data Transfer Object for creating a new Level.
-/// </summary>
-public record CreateLevelDto(
-    string Name,
-    string Code,
-    int Order);
-
-/// <summary>
-/// Data Transfer Object for updating an existing Level.
-/// </summary>
-public record UpdateLevelDto(
-    string Name,
-    string Code,
-    int Order);
-
-/// <summary>
-/// Extension methods for mapping between Level entity and DTOs.
-/// </summary>
-public static class LevelDtoExtensions
-{
-    public static LevelDto ToDto(this Level level) => new(
-        level.Id,
-        level.Name,
-        level.Code,
-        level.Order);
-
-    public static Level ToEntity(this CreateLevelDto dto) =>
-        Level.Create(dto.Name, dto.Code, dto.Order);
-
-    public static void UpdateFromDto(this Level level, UpdateLevelDto dto)
-    {
-        level.UpdateName(dto.Name);
-        level.UpdateCode(dto.Code);
-        level.UpdateOrder(dto.Order);
-    }
-}

GermanApp/Application/DTOs/UserProgressDto.cs

@@ -1,80 +0,0 @@
-using GermanApp.Domain.Entities;
-
-namespace GermanApp.Application.DTOs;
-
-/// <summary>
-/// Data Transfer Object for UserProgress - used for API responses.
-/// This is a read-only representation of a UserProgress entity.
-/// </summary>
-public record UserProgressDto(
-    int Id,
-    int UserId,
-    int LessonId,
-    bool IsCompleted,
-    int QuizScore,
-    DateTime LastAttemptDate,
-    string? LessonTitle = null,
-    string? LevelName = null,
-    string? LevelCode = null);
-
-/// <summary>
-/// Data Transfer Object for creating/updating user progress.
-/// </summary>
-public record UpdateUserProgressDto(
-    int LessonId,
-    bool IsCompleted,
-    int QuizScore);
-
-/// <summary>
-/// Data Transfer Object for level completion summary.
-/// </summary>
-public record LevelCompletionDto(
-    int LevelId,
-    string LevelName,
-    string LevelCode,
-    int TotalLessons,
-    int CompletedLessons,
-    double CompletionPercentage);
-
-/// <summary>
-/// Extension methods for mapping between UserProgress entity and DTOs.
-/// </summary>
-public static class UserProgressDtoExtensions
-{
-    public static UserProgressDto ToDto(this UserProgress userProgress) => new(
-        userProgress.Id,
-        userProgress.UserId,
-        userProgress.LessonId,
-        userProgress.IsCompleted,
-        userProgress.QuizScore,
-        userProgress.LastAttemptDate,
-        userProgress.Lesson?.Title,
-        userProgress.Lesson?.Level?.Name,
-        userProgress.Lesson?.Level?.Code);
-
-    public static UserProgress ToEntity(this UpdateUserProgressDto dto, int userId)
-    {
-        var progress = UserProgress.Create(userId, dto.LessonId);
-        if (dto.IsCompleted)
-        {
-            progress.MarkAsCompleted(dto.QuizScore);
-        }
-        else
-        {
-            progress.UpdateQuizScore(dto.QuizScore);
-        }
-        return progress;
-    }
-
-    public static void UpdateFromDto(this UserProgress userProgress, UpdateUserProgressDto dto)
-    {
-        if (dto.IsCompleted)
-        {
-            userProgress.MarkAsCompleted(dto.QuizScore);
-        }
-        else
-        {
-            userProgress.UpdateQuizScore(dto.QuizScore);
-        }
-    }
-}

GermanApp/Application/Services/LessonService.cs

@@ -1,159 +0,0 @@
-using GermanApp.Application.DTOs;
-using GermanApp.Domain.Entities;
-using GermanApp.Domain.Interfaces;
-
-namespace GermanApp.Application.Services;
-
-/// <summary>
-/// Application service for managing lessons.
-/// This is part of the Application layer.
-/// </summary>
-public class LessonService
-{
-    private readonly ILessonRepository _lessonRepository;
-    private readonly ILevelRepository _levelRepository;
-
-    public LessonService(ILessonRepository lessonRepository, ILevelRepository levelRepository)
-    {
-        _lessonRepository = lessonRepository;
-        _levelRepository = levelRepository;
-    }
-
-    /// <summary>
-    /// Gets all lessons.
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetAllLessonsAsync(CancellationToken cancellationToken = default)
-    {
-        var lessons = await _lessonRepository.GetAllAsync(cancellationToken);
-        return lessons.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Gets all lessons ordered by level and lesson order.
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetAllOrderedLessonsAsync(CancellationToken cancellationToken = default)
-    {
-        var lessons = await _lessonRepository.GetAllOrderedAsync(cancellationToken);
-        return lessons.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Gets a lesson by its ID.
-    /// </summary>
-    public async Task<LessonDto?> GetLessonByIdAsync(int id, CancellationToken cancellationToken = default)
-    {
-        var lesson = await _lessonRepository.GetByIdAsync(id, cancellationToken);
-        return lesson?.ToDto();
-    }
-
-    /// <summary>
-    /// Gets lessons by level ID.
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetLessonsByLevelAsync(int levelId, CancellationToken cancellationToken = default)
-    {
-        var lessons = await _lessonRepository.GetByLevelAsync(levelId, cancellationToken);
-        return lessons.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Gets beginner lessons (A1 and A2 - levels 1 and 2).
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetBeginnerLessonsAsync(CancellationToken cancellationToken = default)
-    {
-        var level1Lessons = await _lessonRepository.GetByLevelAsync(1, cancellationToken);
-        var level2Lessons = await _lessonRepository.GetByLevelAsync(2, cancellationToken);
-        var allLessons = level1Lessons.Concat(level2Lessons)
-            .OrderBy(l => l.LevelId)
-            .ThenBy(l => l.Order)
-            .ToList();
-        return allLessons.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Gets advanced lessons (B2 and C1 - levels 4 and 5).
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetAdvancedLessonsAsync(CancellationToken cancellationToken = default)
-    {
-        var level4Lessons = await _lessonRepository.GetByLevelAsync(4, cancellationToken);
-        var level5Lessons = await _lessonRepository.GetByLevelAsync(5, cancellationToken);
-        var allLessons = level4Lessons.Concat(level5Lessons)
-            .OrderBy(l => l.LevelId)
-            .ThenBy(l => l.Order)
-            .ToList();
-        return allLessons.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Creates a new lesson.
-    /// </summary>
-    public async Task<LessonDto> CreateLessonAsync(CreateLessonDto dto, CancellationToken cancellationToken = default)
-    {
-        // Validate that the level exists
-        var level = await _levelRepository.GetByIdAsync(dto.LevelId, cancellationToken);
-        if (level == null)
-            throw new ArgumentException("Level does not exist");
-
-        var lesson = dto.ToEntity();
-        var createdLesson = await _lessonRepository.AddAsync(lesson, cancellationToken);
-        return createdLesson.ToDto();
-    }
-
-    /// <summary>
-    /// Updates an existing lesson.
-    /// </summary>
-    public async Task<LessonDto?> UpdateLessonAsync(int id, UpdateLessonDto dto, CancellationToken cancellationToken = default)
-    {
-        var lesson = await _lessonRepository.GetByIdAsync(id, cancellationToken);
-        if (lesson == null)
-            return null;
-
-        // Validate that the level exists
-        var level = await _levelRepository.GetByIdAsync(dto.LevelId, cancellationToken);
-        if (level == null)
-            throw new ArgumentException("Level does not exist");
-
-        lesson.UpdateFromDto(dto);
-        await _lessonRepository.UpdateAsync(lesson, cancellationToken);
-        return lesson.ToDto();
-    }
-
-    /// <summary>
-    /// Deletes a lesson by its ID.
-    /// </summary>
-    public async Task<bool> DeleteLessonAsync(int id, CancellationToken cancellationToken = default)
-    {
-        var lesson = await _lessonRepository.GetByIdAsync(id, cancellationToken);
-        if (lesson == null)
-            return false;
-
-        await _lessonRepository.DeleteAsync(lesson, cancellationToken);
-        return true;
-    }
-
-    /// <summary>
-    /// Gets the first lesson in a level.
-    /// </summary>
-    public async Task<LessonDto?> GetFirstLessonInLevelAsync(int levelId, CancellationToken cancellationToken = default)
-    {
-        var lesson = await _lessonRepository.GetFirstLessonInLevelAsync(levelId, cancellationToken);
-        return lesson?.ToDto();
-    }
-
-    /// <summary>
-    /// Gets the next lesson after the specified one.
-    /// </summary>
-    public async Task<LessonDto?> GetNextLessonAsync(int currentLessonId, CancellationToken cancellationToken = default)
-    {
-        var lesson = await _lessonRepository.GetNextLessonAsync(currentLessonId, cancellationToken);
-        return lesson?.ToDto();
-    }
-
-    /// <summary>
-    /// Gets lessons that the user can access (based on completion of previous lessons).
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetAccessibleLessonsAsync(int userId, CancellationToken cancellationToken = default)
-    {
-        var lessons = await _lessonRepository.GetAccessibleLessonsAsync(userId, cancellationToken);
-        return lessons.Select(l => l.ToDto()).ToList();
-    }
-}

GermanApp/Application/Services/LevelService.cs

@@ -1,101 +0,0 @@
-using GermanApp.Application.DTOs;
-using GermanApp.Domain.Entities;
-using GermanApp.Domain.Interfaces;
-
-namespace GermanApp.Application.Services;
-
-/// <summary>
-/// Application service for managing CEFR levels.
-/// This is part of the Application layer.
-/// </summary>
-public class LevelService
-{
-    private readonly ILevelRepository _levelRepository;
-
-    public LevelService(ILevelRepository levelRepository)
-    {
-        _levelRepository = levelRepository;
-    }
-
-    /// <summary>
-    /// Gets all CEFR levels ordered by their sort order.
-    /// </summary>
-    public async Task<IReadOnlyList<LevelDto>> GetAllLevelsAsync(CancellationToken cancellationToken = default)
-    {
-        var levels = await _levelRepository.GetAllOrderedAsync(cancellationToken);
-        return levels.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Gets a level by its ID.
-    /// </summary>
-    public async Task<LevelDto?> GetLevelByIdAsync(int id, CancellationToken cancellationToken = default)
-    {
-        var level = await _levelRepository.GetByIdAsync(id, cancellationToken);
-        return level?.ToDto();
-    }
-
-    /// <summary>
-    /// Gets a level by its code (e.g., "A1", "B2").
-    /// </summary>
-    public async Task<LevelDto?> GetLevelByCodeAsync(string code, CancellationToken cancellationToken = default)
-    {
-        var level = await _levelRepository.GetByCodeAsync(code, cancellationToken);
-        return level?.ToDto();
-    }
-
-    /// <summary>
-    /// Creates a new CEFR level.
-    /// </summary>
-    public async Task<LevelDto> CreateLevelAsync(CreateLevelDto dto, CancellationToken cancellationToken = default)
-    {
-        var level = dto.ToEntity();
-        var createdLevel = await _levelRepository.AddAsync(level, cancellationToken);
-        return createdLevel.ToDto();
-    }
-
-    /// <summary>
-    /// Updates an existing CEFR level.
-    /// </summary>
-    public async Task<LevelDto?> UpdateLevelAsync(int id, UpdateLevelDto dto, CancellationToken cancellationToken = default)
-    {
-        var level = await _levelRepository.GetByIdAsync(id, cancellationToken);
-        if (level == null)
-            return null;
-
-        level.UpdateFromDto(dto);
-        await _levelRepository.UpdateAsync(level, cancellationToken);
-        return level.ToDto();
-    }
-
-    /// <summary>
-    /// Deletes a CEFR level by its ID.
-    /// </summary>
-    public async Task<bool> DeleteLevelAsync(int id, CancellationToken cancellationToken = default)
-    {
-        var level = await _levelRepository.GetByIdAsync(id, cancellationToken);
-        if (level == null)
-            return false;
-
-        await _levelRepository.DeleteAsync(level, cancellationToken);
-        return true;
-    }
-
-    /// <summary>
-    /// Gets the first level (lowest order number) - typically A1.
-    /// </summary>
-    public async Task<LevelDto?> GetFirstLevelAsync(CancellationToken cancellationToken = default)
-    {
-        var level = await _levelRepository.GetFirstLevelAsync(cancellationToken);
-        return level?.ToDto();
-    }
-
-    /// <summary>
-    /// Gets the next level after the specified one.
-    /// </summary>
-    public async Task<LevelDto?> GetNextLevelAsync(int currentLevelId, CancellationToken cancellationToken = default)
-    {
-        var level = await _levelRepository.GetNextLevelAsync(currentLevelId, cancellationToken);
-        return level?.ToDto();
-    }
-}

GermanApp/Application/Services/ProgressService.cs

@@ -1,206 +0,0 @@
-using GermanApp.Application.DTOs;
-using GermanApp.Domain.Entities;
-using GermanApp.Domain.Interfaces;
-
-namespace GermanApp.Application.Services;
-
-/// <summary>
-/// Application service for managing user progress through lessons.
-/// This is part of the Application layer.
-/// </summary>
-public class ProgressService
-{
-    private readonly IUserProgressRepository _userProgressRepository;
-    private readonly ILessonRepository _lessonRepository;
-    private readonly ILevelRepository _levelRepository;
-
-    public ProgressService(
-        IUserProgressRepository userProgressRepository,
-        ILessonRepository lessonRepository,
-        ILevelRepository levelRepository)
-    {
-        _userProgressRepository = userProgressRepository;
-        _lessonRepository = lessonRepository;
-        _levelRepository = levelRepository;
-    }
-
-    /// <summary>
-    /// Gets user progress for a specific lesson.
-    /// </summary>
-    public async Task<UserProgressDto?> GetUserProgressAsync(int userId, int lessonId, CancellationToken cancellationToken = default)
-    {
-        var progress = await _userProgressRepository.GetByUserAndLessonAsync(userId, lessonId, cancellationToken);
-        return progress?.ToDto();
-    }
-
-    /// <summary>
-    /// Gets all progress records for a user.
-    /// </summary>
-    public async Task<IReadOnlyList<UserProgressDto>> GetUserProgressAsync(int userId, CancellationToken cancellationToken = default)
-    {
-        var progressRecords = await _userProgressRepository.GetByUserAsync(userId, cancellationToken);
-        return progressRecords.Select(p => p.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Gets progress for all lessons in a specific level for a user.
-    /// </summary>
-    public async Task<IReadOnlyList<UserProgressDto>> GetUserProgressByLevelAsync(int userId, int levelId, CancellationToken cancellationToken = default)
-    {
-        var progressRecords = await _userProgressRepository.GetByUserAndLevelAsync(userId, levelId, cancellationToken);
-        return progressRecords.Select(p => p.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Checks if a user has completed a lesson.
-    /// </summary>
-    public async Task<bool> HasUserCompletedLessonAsync(int userId, int lessonId, CancellationToken cancellationToken = default)
-    {
-        return await _userProgressRepository.HasUserCompletedLessonAsync(userId, lessonId, cancellationToken);
-    }
-
-    /// <summary>
-    /// Marks a lesson as completed for a user with a quiz score.
-    /// </summary>
-    public async Task<UserProgressDto> MarkLessonAsCompletedAsync(int userId, int lessonId, int quizScore, CancellationToken cancellationToken = default)
-    {
-        var progress = await _userProgressRepository.GetByUserAndLessonAsync(userId, lessonId, cancellationToken);
-        
-        if (progress == null)
-        {
-            // Create new progress record
-            progress = UserProgress.Create(userId, lessonId);
-            progress.MarkAsCompleted(quizScore);
-            await _userProgressRepository.AddAsync(progress, cancellationToken);
-        }
-        else
-        {
-            // Update existing progress record
-            progress.MarkAsCompleted(quizScore);
-            await _userProgressRepository.UpdateAsync(progress, cancellationToken);
-        }
-        
-        return progress.ToDto();
-    }
-
-    /// <summary>
-    /// Updates user progress for a lesson without marking as completed.
-    /// </summary>
-    public async Task<UserProgressDto> UpdateUserProgressAsync(int userId, UpdateUserProgressDto dto, CancellationToken cancellationToken = default)
-    {
-        var progress = await _userProgressRepository.GetByUserAndLessonAsync(userId, dto.LessonId, cancellationToken);
-        
-        if (progress == null)
-        {
-            // Create new progress record
-            progress = dto.ToEntity(userId);
-            await _userProgressRepository.AddAsync(progress, cancellationToken);
-        }
-        else
-        {
-            // Update existing progress record
-            progress.UpdateFromDto(dto);
-            await _userProgressRepository.UpdateAsync(progress, cancellationToken);
-        }
-        
-        return progress.ToDto();
-    }
-
-    /// <summary>
-    /// Resets user progress for a lesson.
-    /// </summary>
-    public async Task<bool> ResetLessonProgressAsync(int userId, int lessonId, CancellationToken cancellationToken = default)
-    {
-        var progress = await _userProgressRepository.GetByUserAndLessonAsync(userId, lessonId, cancellationToken);
-        if (progress == null)
-            return false;
-
-        progress.Reset();
-        await _userProgressRepository.UpdateAsync(progress, cancellationToken);
-        return true;
-    }
-
-    /// <summary>
-    /// Gets the user's average score for a level.
-    /// </summary>
-    public async Task<double> GetAverageScoreForLevelAsync(int userId, int levelId, CancellationToken cancellationToken = default)
-    {
-        return await _userProgressRepository.GetAverageScoreForLevelAsync(userId, levelId, cancellationToken);
-    }
-
-    /// <summary>
-    /// Gets the percentage of lessons completed in a level.
-    /// </summary>
-    public async Task<double> GetLevelCompletionPercentageAsync(int userId, int levelId, CancellationToken cancellationToken = default)
-    {
-        return await _userProgressRepository.GetLevelCompletionPercentageAsync(userId, levelId, cancellationToken);
-    }
-
-    /// <summary>
-    /// Gets level completion summaries for a user.
-    /// </summary>
-    public async Task<IReadOnlyList<LevelCompletionDto>> GetLevelCompletionsAsync(int userId, CancellationToken cancellationToken = default)
-    {
-        var levels = await _levelRepository.GetAllOrderedAsync(cancellationToken);
-        var completions = new List<LevelCompletionDto>();
-
-        foreach (var level in levels)
-        {
-            var lessons = await _lessonRepository.GetByLevelAsync(level.Id, cancellationToken);
-            var completedCount = 0;
-            
-            foreach (var lesson in lessons)
-            {
-                var hasCompleted = await _userProgressRepository.HasUserCompletedLessonAsync(userId, lesson.Id, cancellationToken);
-                if (hasCompleted)
-                    completedCount++;
-            }
-            
-            var percentage = lessons.Count > 0 
-                ? (double)completedCount / lessons.Count * 100 
-                : 0;
-            
-            completions.Add(new LevelCompletionDto(
-                level.Id,
-                level.Name,
-                level.Code,
-                lessons.Count,
-                completedCount,
-                percentage
-            ));
-        }
-        
-        return completions;
-    }
-
-    /// <summary>
-    /// Gets lessons that the user can access (completed previous lessons or first in level).
-    /// </summary>
-    public async Task<IReadOnlyList<LessonDto>> GetAccessibleLessonsAsync(int userId, CancellationToken cancellationToken = default)
-    {
-        var lessons = await _lessonRepository.GetAccessibleLessonsAsync(userId, cancellationToken);
-        return lessons.Select(l => l.ToDto()).ToList();
-    }
-
-    /// <summary>
-    /// Checks if the next lesson in a level is unlocked for the user.
-    /// </summary>
-    public async Task<bool> IsNextLessonUnlockedAsync(int userId, int currentLessonId, CancellationToken cancellationToken = default)
-    {
-        var currentLesson = await _lessonRepository.GetByIdAsync(currentLessonId, cancellationToken);
-        if (currentLesson == null)
-            return false;
-
-        // If this is the first lesson in the level, the next one is always unlocked
-        var firstLesson = await _lessonRepository.GetFirstLessonInLevelAsync(currentLesson.LevelId, cancellationToken);
-        if (firstLesson?.Id == currentLessonId)
-        {
-            var nextLesson = await _lessonRepository.GetNextLessonAsync(currentLessonId, cancellationToken);
-            return nextLesson != null;
-        }
-
-        // Check if the user has completed the current lesson
-        var hasCompleted = await _userProgressRepository.HasUserCompletedLessonAsync(userId, currentLessonId, cancellationToken);
-        return hasCompleted;
-    }
-}

GermanApp/Program.cs

@@ -1,5 +1,4 @@
 using GermanApp.Application.DTOs;
-using GermanApp.Application.Services;
 using GermanApp.Application.Interfaces;
 using GermanApp.Application.UseCases.Commands;
 using GermanApp.Domain.Entities;
@@ -116,20 +115,13 @@ try
     });
 
     // Register repositories (Infrastructure implementations of Domain interfaces)
-    builder.Services.AddScoped<ILevelRepository, LevelRepository>();
     builder.Services.AddScoped<ILessonRepository, LessonRepository>();
-    builder.Services.AddScoped<IUserProgressRepository, UserProgressRepository>();
 
     // ============================================
     // APPLICATION LAYER - Use Cases & Services
     // ============================================
 
     // Register command handlers
-
-    // Register application services
-    builder.Services.AddScoped<LevelService>();
-    builder.Services.AddScoped<LessonService>();
-    builder.Services.AddScoped<ProgressService>();
     builder.Services.AddScoped<ICommandHandler<CreateLessonCommand, LessonDto>, CreateLessonCommandHandler>();
 
     var app = builder.Build();

docs/ROADMAP.md

@@ -91,7 +91,7 @@ Implement the core backend functionality, including lesson management, AI servic
 ### Features
 | # | Feature | Description | Hours | Status | Dependencies |
 |---|---------|-------------|-------|--------|--------------|
-| 2.1 | [Lesson Management](features/lesson-management.md) | Lessons, levels, progress tracking | 10-16h | 🚀 In Progress (Phase 1 & 2 ✅) | Phase 1 |
+| 2.1 | [Lesson Management](features/lesson-management.md) | Lessons, levels, progress tracking | 10-16h | 🚀 In Progress (Phase 1: DB & Models ✅) | Phase 1 |
 | 2.2 | [AI Services](features/ai-services.md) | Mistral, Vosk, Coqui TTS integration | 10-16h | ⏳ Planned | Phase 1 |
 | 2.3 | [Vocabulary System](features/vocabulary-system.md) | Word storage, audio, import | 8-12h | ⏳ Planned | Phase 1, 2.1 |
 | 2.4 | [Quiz System](features/quiz-system.md) | Multiple question types, scoring | 6-10h | ⏳ Planned | Phase 1, 2.1 |

docs/features/lesson-management.md

@@ -12,8 +12,6 @@
 
 **Phase 1: Database & Models - COMPLETED ✅**
 
-**Phase 2: Backend Services - COMPLETED ✅**
-
 ---
 
 ## 📌 Overview
@@ -144,12 +142,12 @@ Each lesson contains:
 - [x] Seed initial A1 level and lessons
 
 ### Phase 2: Backend Services (3-5 hours)
-- [x] Create LevelService with CRUD operations
-- [x] Create LessonService with CRUD operations
-- [x] Create ProgressService to track user progress
-- [x] Implement sequential unlocking logic
-- [x] Create DTOs for Level, Lesson, UserProgress
-- [x] Create mapping profiles (manual extension methods)
+- [ ] Create LevelService with CRUD operations
+- [ ] Create LessonService with CRUD operations
+- [ ] Create ProgressService to track user progress
+- [ ] Implement sequential unlocking logic
+- [ ] Create DTOs for Level, Lesson, UserProgress
+- [ ] Create mapping profiles (AutoMapper or manual)
 
 ### Phase 3: API Controllers (2-3 hours)
 - [ ] Create LevelsController
@@ -194,10 +192,7 @@ Each lesson contains:
 - [x] Create Infrastructure/Data/Repositories/UserProgressRepository.cs
 - [x] Create Application/DTOs/LevelDto.cs
 - [x] Create Application/DTOs/LessonDto.cs
-- [x] Create Application/DTOs/UserProgressDto.cs
-- [x] Create Application/Services/LevelService.cs
-- [x] Create Application/Services/LessonService.cs
-- [x] Create Application/Services/ProgressService.cs
+- [ ] Create Application/DTOs/UserProgressDto.cs
 - [ ] Create Application/Services/LevelService.cs
 - [ ] Create Application/Services/LessonService.cs
 - [ ] Create Application/Services/ProgressService.cs