using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TaskTrackerContracts.BindingModels;
using TaskTrackerContracts.SearchModels;
using TaskTrackerContracts.StoragesContracts;
using TaskTrackerContracts.ViewModels;
using TaskTrackerDatabase.Models;

namespace TaskTrackerDatabase.Implements
{
    public class DirectionStorage : IDirectionStorage
    {
        public List<DirectionViewModel> GetFullList()
        {
            using var context = new TaskTrackerDatabase();
            return context.Directions
             .Include(x => x.Students)
             .ThenInclude(x => x.Student)
             //.ToList()
             .Include(x => x.Subjects)
             .ThenInclude(x => x.Subject)
             .ToList()
             .Select(x => x.GetViewModel)
             .ToList();
        }
        public List<DirectionViewModel> GetFilteredList(DirectionSearchModel model)
        {
            if (string.IsNullOrEmpty(model.Name))
            {
                return new();
            }
            using var context = new TaskTrackerDatabase();
            return context.Directions
				.Include(x => x.Students)
			    .ThenInclude(x => x.Student)
			    .Include(x => x.Subjects)
			    .ThenInclude(x => x.Subject)
				.Where(x => x.Name.Contains(model.Name))
                .ToList()
                .Select(x => x.GetViewModel)
                .ToList();
        }
        public DirectionViewModel? GetElement(DirectionSearchModel model)
        {
            if (string.IsNullOrEmpty(model.Name) && !model.Id.HasValue)
            {
                return null;
            }
            using var context = new TaskTrackerDatabase();
            return context.Directions
				.Include(x => x.Students)
				.ThenInclude(x => x.Student)
				.Include(x => x.Subjects)
				.ThenInclude(x => x.Subject)
				.FirstOrDefault(x => (!string.IsNullOrEmpty(model.Name) && x.Name == model.Name) ||
                                (model.Id.HasValue && x.Id == model.Id))
            ?.GetViewModel;
        }
        public DirectionViewModel? Insert(DirectionBindingModel model)
        {
            using var context = new TaskTrackerDatabase();
            var newReinforced = Direction.Create(context, model);
            if (newReinforced == null)
            {
                return null;
            }
            context.Directions.Add(newReinforced);
            context.SaveChanges();
            return newReinforced.GetViewModel;
        }
        public DirectionViewModel? Update(DirectionBindingModel model)
        {
            using var context = new TaskTrackerDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var reinforced = context.Directions.FirstOrDefault(rec => rec.Id == model.Id);
                if (reinforced == null)
                {
                    return null;
                }
                reinforced.Update(model);
                context.SaveChanges();
                reinforced.UpdateStudents(context, model);
				reinforced.UpdateSubjects(context, model);
				transaction.Commit();
                return reinforced.GetViewModel;
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }
        public DirectionViewModel? Delete(DirectionBindingModel model)
        {
            using var context = new TaskTrackerDatabase();
            var element = context.Directions
			.Include(x => x.Students)
			.FirstOrDefault(rec => rec.Id == model.Id);
            if (element != null)
            {
                context.Directions.Remove(element);
                context.SaveChanges();
                return element.GetViewModel;
            }
            return null;
        }
    }
}