using GermanApp.Domain.Entities;

namespace GermanApp.Application.DTOs;

/// <summary>
/// Data Transfer Object for Quiz - used for API responses.
/// This is a read-only representation of a Quiz entity.
/// </summary>
public record QuizDto(
    int Id,
    int LessonId,
    string LessonTitle,
    string Title,
    string? Description,
    int PassingScore,
    int TimeLimitMinutes,
    bool ShuffleQuestions,
    bool IsActive,
    int QuestionCount,
    int TotalPoints,
    DateTime CreatedAt,
    DateTime? UpdatedAt);

/// <summary>
/// Data Transfer Object for creating a new Quiz.
/// </summary>
public record CreateQuizDto(
    int LessonId,
    string Title,
    string? Description,
    int PassingScore,
    int TimeLimitMinutes,
    bool ShuffleQuestions);

/// <summary>
/// Data Transfer Object for updating an existing Quiz.
/// </summary>
public record UpdateQuizDto(
    int LessonId,
    string Title,
    string? Description,
    int PassingScore,
    int TimeLimitMinutes,
    bool ShuffleQuestions,
    bool IsActive);

/// <summary>
/// Data Transfer Object for quiz with its questions.
/// </summary>
public record QuizWithQuestionsDto(
    int Id,
    int LessonId,
    string LessonTitle,
    string Title,
    string? Description,
    int PassingScore,
    int TimeLimitMinutes,
    bool ShuffleQuestions,
    bool IsActive,
    DateTime CreatedAt,
    DateTime? UpdatedAt,
    IReadOnlyList<QuizQuestionDto> Questions);

/// <summary>
/// Data Transfer Object for quiz list item (summary).
/// </summary>
public record QuizListItemDto(
    int Id,
    int LessonId,
    string LessonTitle,
    string Title,
    bool IsActive,
    int QuestionCount,
    DateTime CreatedAt);

/// <summary>
/// Data Transfer Object for submitting quiz answers.
/// </summary>
public record SubmitQuizDto(
    int QuizId,
    IReadOnlyList<QuizAnswerDto> Answers);

/// <summary>
/// Extension methods for mapping between Quiz entity and DTOs.
/// </summary>
public static class QuizDtoExtensions
{
    public static QuizDto ToDto(this Quiz quiz) => new(
        quiz.Id,
        quiz.LessonId,
        quiz.Lesson?.Title ?? "Unknown",
        quiz.Title,
        quiz.Description,
        quiz.PassingScore,
        quiz.TimeLimitMinutes,
        quiz.ShuffleQuestions,
        quiz.IsActive,
        quiz.Questions?.Count ?? 0,
        quiz.Questions?.Sum(q => q.Points) ?? 0,
        quiz.CreatedAt,
        quiz.UpdatedAt);

    public static QuizListItemDto ToListItemDto(this Quiz quiz) => new(
        quiz.Id,
        quiz.LessonId,
        quiz.Lesson?.Title ?? "Unknown",
        quiz.Title,
        quiz.IsActive,
        quiz.Questions?.Count ?? 0,
        quiz.CreatedAt);

    public static QuizWithQuestionsDto ToQuizWithQuestionsDto(this Quiz quiz) => new(
        quiz.Id,
        quiz.LessonId,
        quiz.Lesson?.Title ?? "Unknown",
        quiz.Title,
        quiz.Description,
        quiz.PassingScore,
        quiz.TimeLimitMinutes,
        quiz.ShuffleQuestions,
        quiz.IsActive,
        quiz.CreatedAt,
        quiz.UpdatedAt,
        quiz.Questions?.OrderBy(q => q.Order).Select(q => q.ToDto()).ToList() ?? new List<QuizQuestionDto>());

    public static Quiz ToEntity(this CreateQuizDto dto) =>
        Quiz.Create(
            dto.LessonId,
            dto.Title,
            dto.Description,
            dto.PassingScore,
            dto.TimeLimitMinutes);

    public static void UpdateFromDto(this Quiz quiz, UpdateQuizDto dto)
    {
        quiz.UpdateLesson(dto.LessonId);
        quiz.UpdateTitle(dto.Title);
        quiz.UpdateDescription(dto.Description);
        quiz.UpdatePassingScore(dto.PassingScore);
        quiz.UpdateTimeLimit(dto.TimeLimitMinutes);
        quiz.UpdateShuffleQuestions(dto.ShuffleQuestions);
        
        if (dto.IsActive != quiz.IsActive)
        {
            if (dto.IsActive)
                quiz.Activate();
            else
                quiz.Deactivate();
        }
    }
}