SUBD_Forum/ForumView/ForumDatabaseImplement/Implements/QuestionStorage.cs

using ForumContracts.BindingModels;
using ForumContracts.SearchModels;
using ForumContracts.StorageContracts;
using ForumContracts.ViewModels;
using ForumDatabaseImplement.Models;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ForumDatabaseImplement.Implements
{
    public class QuestionStorage : IQuestionStorage
    {
        public QuestionViewModel? Delete(QuestionBindingModel model)
        {
            using var context = new ForumDataBase();

            var element = context.Questions
                .Include(x => x.User)
                .Include(x => x.Category)
                .FirstOrDefault(rec => rec.Id == model.Id);

            if (element != null)
            {
                context.Questions.Remove(element);
                context.SaveChanges();

                return element.GetViewModel;
            }

            return null;
        }

        public QuestionViewModel? GetElement(QuestionSearchModel model)
        {
            if (!model.Id.HasValue)
            {
                return null;
            }

            using var context = new ForumDataBase();

            return context.Questions
                    .Include(x => x.User)
                    .Include(x => x.Category)
                    .FirstOrDefault(x => (model.Id.HasValue && x.Id == model.Id))
                    ?.GetViewModel;
        }

        public List<QuestionViewModel> GetFilteredList(QuestionSearchModel model)
        {
            if (model.Id.HasValue)
            {
                var result = GetElement(model);
                return result != null ? new() { result } : new();
            }

            using var context = new ForumDataBase();
            IQueryable<Question>? queryWhere = null;

            if (model.CategoryId.HasValue)
            {
                queryWhere = context.Questions.Where(x => x.CategoryId == model.CategoryId);
            }
            else if (model.UserId.HasValue)
            {
                queryWhere = context.Questions.Where(x => x.UserId == model.UserId);
            }

            else
            {
                return new();
            }

            return queryWhere
                    .Include(x => x.Category)
                    .Include(x => x.User)
                    .Select(x => x.GetViewModel)
                    .ToList();
        }

        public List<QuestionViewModel> HardRequest(QuestionSearchModel model)
        {
            using var context = new ForumDataBase();
            return context.Questions.
                OrderBy(x => x.CreateDate)
                .Include(x => x.Category)
                .Include(x => x.User)
                .Where(x => x.CreateDate.Date >= model.DateFrom.Value.Date && x.CreateDate.Date <= model.DateTo.Value.Date)
                .Select(x=>x.GetViewModel)
                .ToList();
        }

        public List<QuestionViewModel> GetFullList()
        {
            using var context = new ForumDataBase();

            return context.Questions
                .Include(x => x.User)
                .Include(x => x.Category)
                .Select(x => x.GetViewModel).ToList();
        }

        public QuestionViewModel? Insert(QuestionBindingModel model)
        {
            var newQuestion = Question.Create(model);

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

            using var context = new ForumDataBase();

            context.Questions.Add(newQuestion);
            context.SaveChanges();

            return context.Questions
                .Include(x => x.Category)
                .Include(x => x.User)
                .FirstOrDefault(x => x.Id == newQuestion.Id)
                ?.GetViewModel;
        }

        public QuestionViewModel? Update(QuestionBindingModel model)
        {
            using var context = new ForumDataBase();

            var question = context.Questions
                .Include(x => x.Category)
                .Include(x => x.User)
                .FirstOrDefault(x => x.Id == model.Id);

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

            question.Update(model);
            context.SaveChanges();

            return question.GetViewModel;
        }
    }
}