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 Component : IComponentModel
    {
        [Required]
        public string Name { get; private set; } = string.Empty;

        [Required]
        public int Price { get; private set; }

        [Required]
        public int Count { get; private set; }

        private List<(IProviderModel, int, DateTime)>? _componentProviders = null;

        [NotMapped]
        public List<(IProviderModel, int, DateTime)> ComponentProviders
        {
            get
            {
                if (_componentProviders == null)
                {
                    _componentProviders = Providers.Select(recPC => (recPC.Provider as IProviderModel, recPC.Count, recPC.Date)).ToList();
                }
                return _componentProviders;
            }
        }

        [ForeignKey("ComponentId")]
        public virtual List<ComponentProvider> Providers { get; set; } = new();

        public int Id { get; private set; }

        [ForeignKey("ComponentId")]
        public virtual List<ProductComponent> ProductComponents { get; set; } = new();

        public static Component? Create(RestaurantDatabase context, ComponentBindingModel? model)
        {
            if (model == null)
            {
                return null;
            }
            return new Component()
            {
                Id = model.Id,
                Name = model.Name,
                Price = model.Price,
                Count = model.Count,
                Providers = model.ComponentProviders.Select(x => new ComponentProvider
                {
                    Provider = context.Providers.First(y => y.ComponentProviders == x.Item1),
                    Count = x.Item2,
                    Date = x.Item3
                }).ToList()
            };
        }

        public void Update(ComponentBindingModel? model)
        {
            Name = model.Name;
            Price = model.Price;
            Count = model.Count;
        }

        public ComponentViewModel GetViewModel => new()
        {
            Id = Id,
            Name = Name,
            Price = Price,
            Count = Count,
            ComponentProviders = ComponentProviders,
        };

        public void UpdateComponents(RestaurantDatabase context, ComponentBindingModel model)
        {
            var ComponentProviders = context.ComponentProviders.Where(rec => rec.ComponentId == model.Id).ToList();
            if (ComponentProviders != null && ComponentProviders.Count > 0)
            { // удалили те, которых нет в модели
                context.ComponentProviders.RemoveRange(ComponentProviders.Where(rec => !model.ComponentProviders.Select(x => x.Item1.Id).Contains(rec.ProviderId)));
                context.SaveChanges();
                // обновили количество у существующих записей
                foreach (var updateComponent in ComponentProviders)
                {
                    updateComponent.Count = model.ComponentProviders.Find(x => x.Item1.Id == updateComponent.ProviderId).Item2;
                    model.ComponentProviders.Remove(model.ComponentProviders.Find(x => x.Item1.Id == updateComponent.ProviderId));
                }
                context.SaveChanges();
            }
            var Component = context.Components.First(x => x.Id == Id);
            foreach (var pc in model.ComponentProviders)
            {
                context.ComponentProviders.Add(new ComponentProvider
                {
                    Component = Component,
                    Provider = context.Providers.First(x => x.ComponentProviders == pc.Item1),
                    Count = pc.Item2,
                    Date = pc.Item3 // ??????
                });
                context.SaveChanges();
            }
            _componentProviders = null;
        }
    }
}