SUBD-Petrushin-Egor-PIbd-22/TaskTrackerBusinessLogics/BusinessLogic/SubjectLogic.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TaskTrackerContracts.BindingModels;
using TaskTrackerContracts.BusinessLogicsContracts;
using TaskTrackerContracts.SearchModels;
using TaskTrackerContracts.StoragesContracts;
using TaskTrackerContracts.ViewModels;

namespace TaskTrackerBusinessLogics.BusinessLogic
{
    public class StudentLogic : IStudentLogic
    {
        private readonly IStudentStorage _studentStorage;
        public StudentLogic(IStudentStorage studentStorage)
        {
            _studentStorage = studentStorage;
        }

        public List<StudentViewModel>? ReadList(StudentSearchModel? model)
        {
            var list = model == null ? _studentStorage.GetFullList() : _studentStorage.GetFilteredList(model);
            if (list == null)
            {
                return null;
            }
            return list;
        }

        public StudentViewModel? ReadElement(StudentSearchModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            var element = _studentStorage.GetElement(model);
            if (element == null)
            {
                return null;
            }
            return element;
        }

        public bool Create(StudentBindingModel model)
        {
            CheckModel(model);
            if (_studentStorage.Insert(model) == null)
            {
                return false;
            }
            return true;
        }

        public bool Update(StudentBindingModel model)
        {
            CheckModel(model);
            if (_studentStorage.Update(model) == null)
            {
                return false;
            }
            return true;
        }

        public bool Delete(StudentBindingModel model)
        {
            CheckModel(model, false);
            if (_studentStorage.Delete(model) == null)
            {
                return false;
            }
            return true;
        }

        private void CheckModel(StudentBindingModel model, bool withParams = true)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            if (!withParams)
            {
                return;
            }
            var element = _studentStorage.GetElement(new StudentSearchModel
            {
                Name = model.Name
            });
            if (element != null && element.Id != model.Id)
            {
                throw new InvalidOperationException("Пользователя с таким логином(почтой) уже есть");
            }
        }
    }

}