using RestaurantContracts.BindingModels;
using RestaurantContracts.ViewModels;
using RestaurantDataModels.Models;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace RestaurantDatabaseImplement.Models
{
    public class Order : IOrderModel
    {
        [Required]
        public int ClientId { get; set; }
        public virtual Client Client { get; set; } = new();

        [Required]
        public double Price { get; set; }

        [Required]
        public DateTime Date { get; set; }

        private Dictionary<int, (IProductModel, int)>? _orderProducts = null;

        [NotMapped]
        public Dictionary<int, (IProductModel, int)> OrderProducts
        {
            get
            {
                if (_orderProducts == null)
                {
                    _orderProducts = Products.ToDictionary(recPC => recPC.ProductId, recPC =>
                   (recPC.Product as IProductModel, recPC.Count));
                }
                return _orderProducts;
            }
        }

        [ForeignKey("OrderId")]
        public virtual List<OrderProduct> Products { get; set; } = new();

        public int Id { get; set; }

        public static Order? Create(RestaurantDatabase context, OrderBindingModel? model)
        {
            if (model == null)
            {
                return null;
            }
            return new Order()
            {
                Id = model.Id,
                ClientId = model.ClientId,
                Client = context.Clients.FirstOrDefault(x => x.Id == model.ClientId),
                Price = model.Price,
                Date = model.Date,
                Products = model.OrderProducts.Select(x => new OrderProduct
                {
                    Product = context.Products.First(y => y.Id == x.Key),
                    Count = x.Value.Item2
                }).ToList()
            };
        }

        public void Update(OrderBindingModel? model)
        {
            Date = model.Date;
            Price = model.Price;
        }

        public OrderViewModel GetViewModel => new()
        {
            Id = Id,
            ClientId = ClientId,
            ClientFirstName = Client.FirstName,
            ClientLastName = Client.LastName,
            Price = Price,
            Date = Date,
        };

        public void UpdateComponents(RestaurantDatabase context, OrderBindingModel model)
        {
            var OrderProducts = context.OrderProducts.Where(rec => rec.OrderId == model.Id).ToList();
            if (OrderProducts != null && OrderProducts.Count > 0)
            { // удалили те, которых нет в модели
                context.OrderProducts.RemoveRange(OrderProducts.Where(rec => !model.OrderProducts.ContainsKey(rec.ProductId)));
                context.SaveChanges();
                // обновили количество у существующих записей
                foreach (var updateComponent in OrderProducts)
                {
                    updateComponent.Count = model.OrderProducts[updateComponent.ProductId].Item2;
                    model.OrderProducts.Remove(updateComponent.ProductId);
                }
                context.SaveChanges();
            }
            var Order = context.Orders.First(x => x.Id == Id);
            foreach (var pc in model.OrderProducts)
            {
                context.OrderProducts.Add(new OrderProduct
                {
                    Order = Order,
                    Product = context.Products.First(x => x.Id == pc.Key),
                    Count = pc.Value.Item2
                });
                context.SaveChanges();
            }
            _orderProducts = null;
        }
    }
}