using DinerContracts.BindingModels;
using DinerContracts.ViewModels;
using DinerDataModels.Models;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace DinerDataBaseImplement.Models
{
    public class Snack : ISnackModel
    {
        public int Id { get; set; }
        [Required]
        public string SnackName { get; set; } = string.Empty;
        [Required]
        public double Price { get; set; }
        private Dictionary<int, (IComponentModel, int)>? _snackComponents = null; 
        [NotMapped]
        public Dictionary<int, (IComponentModel, int)> SnackComponents
        {
            get
            {
                if (_snackComponents == null)
                {
                    _snackComponents = Components
                    .ToDictionary(recPC => recPC.ComponentId, recPC => (recPC.Component as IComponentModel, recPC.Count));
                }
                return _snackComponents;
            }
        }
        [ForeignKey("SnackId")]
        public virtual List<SnackComponent> Components { get; set; } = new();
        [ForeignKey("SnackId")]
        public virtual List<Order> Orders { get; set; } = new();
        public static Snack Create(DinerDatabase context, SnackBindingModel model)
        {
            return new Snack()
            {
                Id = model.Id,
                SnackName = model.SnackName,
                Price = model.Price,
                Components = model.SnackComponents.Select(x => new SnackComponent
                {
                    Component = context.Components.First(y => y.Id == x.Key),
                    Count = x.Value.Item2
                }).ToList()
            };
        }
        public void Update(SnackBindingModel model)
        {
            SnackName = model.SnackName;
            Price = model.Price;
        }
        public SnackViewModel GetViewModel => new()
        {
            Id = Id,
            SnackName = SnackName,
            Price = Price,
            SnackComponents = SnackComponents
        };
        public void UpdateComponents(DinerDatabase context, SnackBindingModel model)
        {
            var snackComponents = context.SnackComponents.Where(rec => rec.SnackId == model.Id).ToList();
            if (snackComponents != null && snackComponents.Count > 0)
            { // удалили те, которых нет в модели
                context.SnackComponents.RemoveRange(snackComponents.Where(rec => !model.SnackComponents.ContainsKey(rec.ComponentId)));
                context.SaveChanges();
                // обновили количество у существующих записей
                foreach (var updateComponent in snackComponents)
                {
                    updateComponent.Count = model.SnackComponents[updateComponent.ComponentId].Item2;
                    model.SnackComponents.Remove(updateComponent.ComponentId);
                }
                context.SaveChanges();
            }
            var snack = context.Snacks.First(x => x.Id == Id);
            foreach (var pc in model.SnackComponents)
            {
                context.SnackComponents.Add(new SnackComponent
                {
                    Snack = snack,
                    Component = context.Components.First(x => x.Id == pc.Key),
                    Count = pc.Value.Item2
                });
                context.SaveChanges();
            }
            _snackComponents = null;
        }
    }
}