using DinerContracts.BindingModels;
using DinerContracts.SearchModels;
using DinerContracts.StoragesContracts;
using DinerContracts.ViewModels;
using DinerDataBaseImplement.Models;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Conventions;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DinerDataBaseImplement.Implements
{
    public class SnackStorage : ISnackStorage
    {
        public SnackViewModel? Delete(SnackBindingModel model)
        {
            using var context = new DinerDataBase();
            var element = context.Snacks
                .Include(x => x.Components)
                .Include(x => x.Orders)
                .FirstOrDefault(rec => rec.ID == model.ID);
            if (element != null)
            {
                context.Snacks.Remove(element);
                context.SaveChanges();
                return element.GetViewModel;
            }
            return null;
        }

        public SnackViewModel? GetElement(SnackSearchModel model)
        {
            if (string.IsNullOrEmpty(model.ProductName) && !model.ID.HasValue) { 
                return null; 
            }
            using var context = new DinerDataBase();
            return context.Snacks
                .Include(x => x.Components)
                .ThenInclude(x => x.Component)
                .FirstOrDefault(x => (!string.IsNullOrEmpty(model.ProductName) && x.ProductName == model.ProductName) ||
                                (model.ID.HasValue && x.ID == model.ID))
                                ?.GetViewModel;
        }

        public List<SnackViewModel> GetFilteredList(SnackSearchModel model)
        {
            if (string.IsNullOrEmpty(model.ProductName)) { 
                return new(); 
            }
            using var context = new DinerDataBase();
            return context.Snacks
                    .Include(x => x.Components)
                    .ThenInclude(x => x.Component)
                    .Where(x => x.ProductName.Contains(model.ProductName))
                    .ToList()
                    .Select(x => x.GetViewModel).ToList();
        }

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

        public SnackViewModel? Insert(SnackBindingModel model)
        {
            using var context = new DinerDataBase();
            var newProduct = Snack.Create(context, model);
            if (newProduct == null) { 
                return null; 
            }
            context.Snacks.Add(newProduct);
            context.SaveChanges();
            return newProduct.GetViewModel;
        }

        public SnackViewModel? Update(SnackBindingModel model)
        {
            using var context = new DinerDataBase();
            using var transcation = context.Database.BeginTransaction();
            try
            {
                var product = context.Snacks.FirstOrDefault(rec => rec.ID == model.ID);
                if (product == null) {
                    return null;
                }
                product.Update(model);
                context.SaveChanges();
                product.UpdateComponents(context, model);
                transcation.Commit();
                return product.GetViewModel;
            }
            catch
            {
                transcation.Rollback();
                throw;
            }
        }
    }
}