using System.ComponentModel.DataAnnotations.Schema;
using System.ComponentModel.DataAnnotations;
using TravelAgencyContracts.BindingModels;
using TravelAgencyContracts.ViewModels;
using TravelAgencyDataModels.Models;
using Microsoft.EntityFrameworkCore;

namespace TravelAgencyDatabaseImplement.Models
{
    public class ExcursionGroup : IExcursionGroupModel
    {
        public int Id { get; set; }

        [Required]
        public string ExcursionGroupName { get; set; } = string.Empty;

        [Required]
        public int ParticipantsAmount { get; set; }

        [Required]
        public int UserId { get; set; }

        [DeleteBehavior(DeleteBehavior.Restrict)]
        public virtual User User { get; set; }

        [Required]
        public int GuideId { get; set; }

        public virtual Guide Guide { get; set; }

        private Dictionary<int, ITourModel>? _excursionGroupTours = null;

        [NotMapped]
        public Dictionary<int, ITourModel> ExcursionGroupTours
        {
            get
            {
                if (_excursionGroupTours == null)
                {
                    _excursionGroupTours = Tours
                            .ToDictionary(recPC => recPC.TourId, recPC => recPC.Tour as ITourModel);
                }
                return _excursionGroupTours;
            }
        }

        [ForeignKey("ExcursionGroupId")]
        public virtual List<ExcursionGroupTour> Tours { get; set; } = new();

        public static ExcursionGroup? Create(TravelAgencyDatabase context, ExcursionGroupBindingModel? model)
        {
            if (model == null)
            {
                return null;
            }
            return new ExcursionGroup()
            {
                Id = model.Id,
                ExcursionGroupName = model.ExcursionGroupName,
                ParticipantsAmount = model.ParticipantsAmount,
                UserId = model.UserId,
                GuideId = model.GuideId,
                Guide = context.Guides
                    .First(x => x.Id == model.GuideId),
                Tours = model.ExcursionGroupTours.Select(x => new ExcursionGroupTour
                {
                    Tour = context.Tours.First(y => y.Id == x.Key)
                }).ToList()
            };
        }
        public void Update(ExcursionGroupBindingModel? model)
        {
            if (model == null)
            {
                return;
            }
            ExcursionGroupName = model.ExcursionGroupName;
            ParticipantsAmount = model.ParticipantsAmount;
        }

        public ExcursionGroupViewModel GetViewModel => new()
        {
            Id = Id,
            ExcursionGroupName = ExcursionGroupName,
            ParticipantsAmount = ParticipantsAmount,
            UserId = UserId,
            GuideId = GuideId,
            GuideFIO = Guide.GuideFIO,
            ExcursionGroupTours = ExcursionGroupTours
        };

        public void UpdateTours(TravelAgencyDatabase context, ExcursionGroupBindingModel model)
        {
            var excursionGroupTours = context.ExcursionGroupTours.Where(rec => rec.ExcursionGroupId == model.Id).ToList();
            if (excursionGroupTours != null && excursionGroupTours.Count > 0)
            {   // удалили те, которых нет в модели
                context.ExcursionGroupTours.RemoveRange(excursionGroupTours.Where(rec => !model.ExcursionGroupTours.ContainsKey(rec.TourId)));
                context.SaveChanges();
            }
            var excursionGroup = context.ExcursionGroups.First(x => x.Id == Id);
            foreach (var et in model.ExcursionGroupTours)
            {
                context.ExcursionGroupTours.Add(new ExcursionGroupTour
                {
                    ExcursionGroup = excursionGroup,
                    Tour = context.Tours.First(x => x.Id == et.Key)
                });
                context.SaveChanges();
            }
            _excursionGroupTours = null;
        }
    }
}