using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using ConfectioneryContracts.BindingModels;
using ConfectioneryContracts.ViewModels;
using ConfectioneryDataModels.Models;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Runtime.Serialization;


namespace ConfectioneryDatabaseImplement.Models
{
	[DataContract]
	public class Pastry : IPastryModel
    {
		[DataMember]
		public int Id { get; set; }
		[DataMember]
		[Required]
        public string PastryName { get; set; } = string.Empty;
		[DataMember]
		[Required]
        public double Price { get; set; }
        private Dictionary<int, (IComponentModel, int)>? _pastryComponents = null;
		[DataMember]
		[NotMapped]
		public Dictionary<int, (IComponentModel, int)> PastryComponents
        {
            get
            {
                if (_pastryComponents == null)
                {
                    _pastryComponents = Components
                    .ToDictionary(recPC => recPC.ComponentId, recPC =>
                   (recPC.Component as IComponentModel, recPC.Count));
                }
                return _pastryComponents;
            }
        }
        [ForeignKey("PastryId")]
        public virtual List<PastryComponent> Components { get; set; } = new();
        [ForeignKey("PastryId")]
        public virtual List<Order> Orders { get; set; } = new();
        public static Pastry Create(ConfectioneryDatabase context, PastryBindingModel model)
        {
            return new Pastry()
            {
                Id = model.Id,
                PastryName = model.PastryName,
                Price = model.Price,
                Components = model.PastryComponents.Select(x => new PastryComponent
                {
                    Component = context.Components.First(y => y.Id == x.Key),
                    Count = x.Value.Item2
                }).ToList()
            };
        }
        public void Update(PastryBindingModel model)
        {
            PastryName = model.PastryName;
            Price = model.Price;
        }
        public PastryViewModel GetViewModel => new()
        {
            Id = Id,
            PastryName = PastryName,
            Price = Price,
            PastryComponents = PastryComponents
        };
        public void UpdateComponents(ConfectioneryDatabase context, PastryBindingModel model)
        {
            var pastryComponents = context.PastryComponents.Where(rec => rec.PastryId == model.Id).ToList();
            if (pastryComponents != null && pastryComponents.Count > 0)
            { // удалили те, которых нет в модели
                context.PastryComponents.RemoveRange(pastryComponents.Where(rec => !model.PastryComponents.ContainsKey(rec.ComponentId)));
                context.SaveChanges();
                // обновили количество у существующих записей
                foreach (var updateComponent in pastryComponents)
                {
                    updateComponent.Count = model.PastryComponents[updateComponent.ComponentId].Item2;
                    model.PastryComponents.Remove(updateComponent.ComponentId);
                }
                context.SaveChanges();
            }
            var pastry = context.Pastrys.First(x => x.Id == Id);
            foreach (var pc in model.PastryComponents)
            {
                context.PastryComponents.Add(new PastryComponent
                {
                    Pastry = pastry,
                    Component = context.Components.First(x => x.Id == pc.Key),
                    Count = pc.Value.Item2
                });
                context.SaveChanges();
            }
            _pastryComponents = null;
        }
    }
}