using AutomobilePlantContracts.StorageContracts;
using AutomobilePlantContracts.BindingModels;
using AutomobilePlantContracts.SearchModels;
using AutomobilePlantContracts.ViewModels;
using AutomobilePlantDatabaseImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection.Metadata;
using System.Text;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using System.Xml.Linq;

namespace AutomobilePlantDatabaseImplement.Implements
{
    public class CarStorage : ICarStorage
    {
        public CarViewModel? GetElement(CarSearchModel model)
        {
            if (string.IsNullOrEmpty(model.CarName) && !model.Id.HasValue)
            {
                return null;
            }
            using var context = new AutomobilePlantDatabase();
            return context.Cars.Include(x => x.Components)
            .ThenInclude(x => x.Component)
            .FirstOrDefault(x => (!string.IsNullOrEmpty(model.CarName) &&
            x.CarName == model.CarName) ||
            (model.Id.HasValue && x.Id == model.Id))
            ?.GetViewModel;
        }

        public List<CarViewModel> GetFilteredList(CarSearchModel model)
        {
            if (string.IsNullOrEmpty(model.CarName))
            {
                return new();
            }
            using var context = new AutomobilePlantDatabase();
            return context.Cars
            .Include(x => x.Components)
            .ThenInclude(x => x.Component)
            .Where(x => x.CarName.Contains(model.CarName))
            .ToList()
            .Select(x => x.GetViewModel)
            .ToList();
        }

        public List<CarViewModel> GetFullList()
        {
            using var context = new AutomobilePlantDatabase();
            return context.Cars
            .Include(x => x.Components)
            .ThenInclude(x => x.Component)
            .ToList()
            .Select(x => x.GetViewModel)
            .ToList();
        }

        public CarViewModel? Insert(CarBindingModel model)
        {
            using var context = new AutomobilePlantDatabase();
            using var transaction = context.Database.BeginTransaction();
            {
                try
                {
                    var newCar = Car.Create(context, model);
                    if (newCar == null)
                    {
                        transaction.Rollback();
                        return null;
                    }
                    context.Cars.Add(newCar);

                    context.SaveChanges();
                    context.Database.CommitTransaction();

                    return newCar.GetViewModel;
                }
                catch (Exception)
                {
                    transaction.Rollback();
                    return null;
                }
            }
        }

        public CarViewModel? Update(CarBindingModel model)
        {
            using var context = new AutomobilePlantDatabase();
            using var transaction = context.Database.BeginTransaction();
            {
                try
                {
                    var car = context.Cars.FirstOrDefault(x => x.Id == model.Id);
                    if (car == null)
                    {
                        transaction.Rollback();
                        return null;
                    }

                    car.Update(model);
                    car.UpdateComponents(context, model);

                    context.SaveChanges();
                    context.Database.CommitTransaction();

                    return car.GetViewModel;
                }
                catch (Exception)
                {
                    transaction.Rollback();
                    return null;
                }
            }
        }
        public CarViewModel? Delete(CarBindingModel model)
        {
            using var context = new AutomobilePlantDatabase();
            var element = context.Cars.FirstOrDefault(rec => rec.Id == model.Id);
            if (element != null)
            {
                context.Cars.Remove(element);
                context.SaveChanges();
                return element.GetViewModel;
            }
            return null;
        }
    }
}