using ComputerShopContracts.BindingModels;
using ComputerShopContracts.SearchModels;
using ComputerShopContracts.StorageContracts;
using ComputerShopContracts.ViewModels;
using ComputerShopDatabaseImplement.Models;
using Microsoft.EntityFrameworkCore;

namespace ComputerShopDatabaseImplement.Implements
{
    public class AssemblyStorage : IAssemblyStorage
    {
        public List<AssemblyViewModel> GetFullList()
        {
            using var Context = new ComputerShopDatabase();

            return Context.Assemblies
                .Include(x => x.Components)
                    .ThenInclude(x => x.Assembly)
                .Select(x => x.ViewModel)
                .ToList();
        }

        public List<AssemblyViewModel> GetFilteredList(AssemblySearchModel Model)
        {
            using var Context = new ComputerShopDatabase();
            // сборки по комплектующим
            return Context.Assemblies
                .Include(x => x.Components)
                    .ThenInclude(x => x.Assembly)
                .Select(x => x.ViewModel)
                .ToList();
        }

        public AssemblyViewModel? GetElement(AssemblySearchModel Model)
        {
            using var Context = new ComputerShopDatabase();

            return Context.Assemblies
                .Include(x => x.Components)
                    .ThenInclude(x => x.Assembly)
                .FirstOrDefault(x => x.Id == Model.Id)?
                .ViewModel;
        }

        public AssemblyViewModel? Insert(AssemblyBindingModel Model)
        {
            using var Context = new ComputerShopDatabase();

            var NewAssembly = Assembly.Create(Context, Model);
            Context.Assemblies.Add(NewAssembly);
            Context.SaveChanges();

            return NewAssembly.ViewModel;
        }

        public AssemblyViewModel? Update(AssemblyBindingModel Model)
        {
            using var Context = new ComputerShopDatabase();
            using var Transaction = Context.Database.BeginTransaction();

            try
            {
                var ExistingAssembly = Context.Assemblies.FirstOrDefault(x => x.Id == Model.Id);
                if (ExistingAssembly == null)
                {
                    return null;
                }

                ExistingAssembly.Update(Model);
                Context.SaveChanges();
                ExistingAssembly.UpdateComponents(Context, Model);
                Transaction.Commit();

                return ExistingAssembly.ViewModel;
            }
            catch
            {
                Transaction.Rollback();
                throw;
            }
        }

        public AssemblyViewModel? Delete(AssemblyBindingModel Model)
        {
            using var Context = new ComputerShopDatabase();

            var ExistingAssembly = Context.Assemblies.Include(x => x.Components).FirstOrDefault(x => x.Id == Model.Id);
            if (ExistingAssembly == null)
            {
                return null;
            }

            Context.Assemblies.Remove(ExistingAssembly);
            Context.SaveChanges();

            return ExistingAssembly.ViewModel;
        }
    }
}