ISEbd-21_Agliullov.D.A._Confectionery/ConfectionaryListImplement/GroupStorage.cs

using ConfectioneryListImplement;
using EkzamenContracts.BindingModels;
using EkzamenContracts.SearchModels;
using EkzamenContracts.StoragesContract;
using EkzamenContracts.ViewModels;

namespace EkzamenListImplement
{
    public class GroupStorage : IGroupStorage
    {
        private readonly DataListSingleton _source;
        public GroupStorage()
        {
            _source = DataListSingleton.GetInstance();
        }

        public GroupViewModel? Delete(GroupBindingModel model)
        {
            var group = _source.Groups.FirstOrDefault(x => x.Id == model.Id);
            if (group != null)
            {
                _source.Groups.Remove(group);
            }
            return group?.GetViewModel;
        }

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

            return _source.Groups.FirstOrDefault(x => x.Id == model.Id)?.GetViewModel;
        }

        public List<GroupViewModel> GetFilteredList(GroupSearchModel model)
        {
            var result = new List<GroupViewModel>();
            if (!model.Id.HasValue)
            {
                return result;
            }

            return new() { GetElement(model) };
        }

        public List<GroupViewModel> GetFullList()
        {
            return _source.Groups.Select(x => x.GetViewModel).ToList();
        }

        public GroupViewModel? Insert(GroupBindingModel model)
        {
            model.Id = _source.Groups.Max(x => x.Id);
            var newOrder = Group.Create(model);
            if (newOrder == null)
            {
                return null;
            }
            _source.Groups.Add(newOrder);
            return newOrder.GetViewModel;
        }

        public GroupViewModel? Update(GroupBindingModel model)
        {
            var group = _source.Groups.FirstOrDefault(x => x.Id == model.Id);
            group?.Update(model);
            return group?.GetViewModel;
            return null;
        }
    }
}