using Entities.Contracts;
using Entities.DTO;
using Microsoft.EntityFrameworkCore;
using SharedDATA.Api;
using TechHelper.Repository;

namespace TechHelper.Server.Repositories
{
	public class ExamRepository : IExamRepository
	{
		private readonly IUnitOfWork _unitOfWork;
		private readonly IRepository<Assignment> _assignmentRepo;
		private readonly IRepository<Question> _questionRepo;
		private readonly IRepository<AssignmentQuestion> _assignQuestionRepo;

		public ExamRepository(IUnitOfWork unitOfWork)
		{
			_unitOfWork = unitOfWork;
			_assignmentRepo = _unitOfWork.GetRepository<Assignment>();
			_assignQuestionRepo = _unitOfWork.GetRepository<AssignmentQuestion>();	
		}

		public async Task<Assignment?> GetFullExamByIdAsync(Guid assignmentId)
		{
			var result = await _assignmentRepo.GetFirstOrDefaultAsync(
				predicate:
					a => a.Id == assignmentId,
				include:
					i => i.Include(a => a.ExamStruct)
				);

			result.ExamStruct = await GetNeed(result.ExamStructId)?? null;

			return result;
		}


		public async Task<AssignmentQuestion?> GetNeed(Guid id) 
		{
			var result = await _assignQuestionRepo.GetFirstOrDefaultAsync(
				predicate: aq => aq.Id == id,
				include: i => i
					.Include(aq => aq.ChildrenAssignmentQuestion) 
					.Include(aq => aq.Question)
						.ThenInclude(q => q.Lesson)
					.Include(aq => aq.Question)
						.ThenInclude(q => q.KeyPoint)
			);

			if (result == null)
			{
				return null;
			}

			var loadedChildren = new List<AssignmentQuestion>();
			foreach (var child in result.ChildrenAssignmentQuestion)
			{
				var loadedChild = await GetNeed(child.Id); 
				if (loadedChild != null)
				{
					loadedChildren.Add(loadedChild);
				}
			}
			result.ChildrenAssignmentQuestion = loadedChildren; 

			return result;
		}



		public async Task<IEnumerable<Assignment>> GetExamPreviewsByUserAsync(Guid userId)
		{
			return await _assignmentRepo.GetAllAsync(
				predicate: a => a.CreatorId == userId && !a.IsDeleted);
		}

		public async Task AddAsync(Assignment assignment)
		{
			await _assignmentRepo.InsertAsync(assignment);
		}

		public async Task AddAsync(AssignmentQuestion assignment)
		{
		}

		public async Task AddAsync(Question assignment)
		{
		}

		public async Task AddAsync(AssignmentClass assignment)
		{
		}
	}
}