using PersonnelDepartmentContracts.BindingModels;
using PersonnelDepartmentContracts.SearchModels;
using PersonnelDepartmentContracts.StoragesContracts;
using PersonnelDepartmentContracts.ViewModels;
using PersonnelDepartmentDatabaseImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace PersonnelDepartmentDatabaseImplement.Implements
{
	public class PositionStorage : IPositionStorage
	{
		public PositionViewModel? Delete(PositionBindingModel model)
		{
			using var context = new PersonnelDepartmentDatabase();
			var element = context.Positions
				.FirstOrDefault(x => x.Id == model.Id);
			if (element == null)
			{
				return null;
			}
			context.Positions.Remove(element);
			return element.GetViewModel;
		}

		public PositionViewModel? GetElement(PositionSearchModel model)
		{
			if (!model.Id.HasValue)
			{
				return null;
			}
			using var context = new PersonnelDepartmentDatabase();
			return context.Positions
				.FirstOrDefault(x => (model.Id.HasValue && x.Id == model.Id) ||
				(!string.IsNullOrEmpty(model.Name) && x.Name == model.Name))?.GetViewModel;
		}

		public List<PositionViewModel> GetFilteredList(PositionSearchModel model)
		{
			using var context = new PersonnelDepartmentDatabase();
			return context.Positions
				.Where(x => (model.Id.HasValue && x.Id == model.Id) ||
				(!string.IsNullOrEmpty(model.Name) && x.Name == model.Name))
				.Select(x => x.GetViewModel).ToList();
		}

		public List<PositionViewModel> GetFullList()
		{
			using var context = new PersonnelDepartmentDatabase();
			return context.Positions
				.Select(x => x.GetViewModel)
				.ToList();
		}

		public PositionViewModel? Insert(PositionBindingModel model)
		{
			var newElement = Position.Create(model);
			if (newElement == null)
			{
				return null;
			}
			using var context = new PersonnelDepartmentDatabase();
			context.Positions.Add(newElement);
			context.SaveChanges();
			return newElement.GetViewModel;
		}

		public PositionViewModel? Update(PositionBindingModel model)
		{
			using var context = new PersonnelDepartmentDatabase();
			var element = context.Positions
				.FirstOrDefault(x => x.Id == model.Id);
			if (element == null)
			{
				return null;
			}
			element.Update(model);
			context.SaveChanges();
			return element.GetViewModel;
		}
	}
}