using AbstractLawFirmContracts.BindingModels;
using AbstractLawFirmContracts.SearchModels;
using AbstractLawFirmContracts.StoragesContracts;
using AbstractLawFirmContracts.ViewModels;
using AbstractLawFirmDataModels.Models;
using AbstractLawFirmDatabaseImplement.Models;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AbstractLawFirmDatabaseImplement.Implements
{
    public class ShopStorage : IShopStorage
    {
        public ShopViewModel? GetElement(ShopSearchModel model)
        {
            if (string.IsNullOrEmpty(model.ShopName) && !model.Id.HasValue)
            {
                return new();
            }
            using var context = new AbstractLawFirmDatabase();
            return context.Shops.Include(x => x.Documents).ThenInclude(x => x.Document).FirstOrDefault(x =>
                (!string.IsNullOrEmpty(model.ShopName) && x.ShopName == model.ShopName) ||
                (model.Id.HasValue && x.Id == model.Id))?.GetViewModel;
        }
        public List<ShopViewModel> GetFilteredList(ShopSearchModel model)
        {
            if (string.IsNullOrEmpty(model.ShopName))
            {
                return new();
            }
            using var context = new AbstractLawFirmDatabase();
            return context.Shops.Include(x => x.Documents).ThenInclude(x => x.Document).Where(x => x.ShopName.Contains(model.ShopName)).ToList().Select(x => x.GetViewModel).ToList();
        }
        public List<ShopViewModel> GetFullList()
        {
            using var context = new AbstractLawFirmDatabase();
            return context.Shops.Include(x => x.Documents).ThenInclude(x => x.Document).ToList().Select(x => x.GetViewModel).ToList();
        }
        public ShopViewModel? Insert(ShopBindingModel model)
        {
            using var context = new AbstractLawFirmDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var newShop = Shop.Create(context, model);
                if (newShop == null)
                {
                    return null;
                }
                if (context.Shops.Any(x => x.ShopName == newShop.ShopName))
                {
                    throw new Exception("Название магазина уже занято");
                }

                context.Shops.Add(newShop);
                context.SaveChanges();
                transaction.Commit();
                return newShop.GetViewModel;
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }
        public ShopViewModel? Update(ShopBindingModel model)
        {
            using var context = new AbstractLawFirmDatabase();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var shop = context.Shops.Include(x => x.Documents).FirstOrDefault(x => x.Id == model.Id);
                if (shop == null)
                {
                    return null;
                }
                shop.Update(model);
                context.SaveChanges();
                if (model.ShopDocuments.Count > 0)
                {
                    shop.UpdateDocuments(context, model);
                }
                transaction.Commit();
                return shop.GetViewModel;
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }
        public ShopViewModel? Delete(ShopBindingModel model)
        {
            using var context = new AbstractLawFirmDatabase();
            var shop = context.Shops.Include(x => x.Documents).FirstOrDefault(x => x.Id == model.Id);
            if (shop != null)
            {
                context.Shops.Remove(shop);
                context.SaveChanges();
                return shop.GetViewModel;
            }
            return null;
        }
        public bool SellDocument(IDocumentModel model, int count)
        {
            using var context = new AbstractLawFirmDatabase();
            using var transaction = context.Database.BeginTransaction();

            foreach (var shopDocuments in context.ShopDocuments.Where(x => x.DocumentId == model.Id))
            {
                var min = Math.Min(count, shopDocuments.Count);
                shopDocuments.Count -= min;
                count -= min;
                if (count <= 0)
                {
                    break;
                }
            }

            if (count == 0)
            {
                context.SaveChanges();
                transaction.Commit();
            }
            else
                transaction.Rollback();

            if (count > 0)
                return false;

            return true;
        }
    }
}