using SchoolAgainStudyContracts.BindingModel;
using SchoolAgainStudyContracts.ViewModel;
using SchoolAgainStudyDataModels.Models;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Security.Claims;
using System.Text;
using System.Threading.Tasks;

namespace SchoolAgainStudyDataBaseImplements.Models
{
    public class Teacher : ITeacher
    {
        [Required]
        public string Name { get; set; } = string.Empty;
        [Required]
        public string Post { get; set; } = string.Empty;
        [Required]
        public string Phone { get; set; } = string.Empty;
        [Required]
        public string Login { get; set; } = string.Empty;
        [Required]
        public string Password { get; set; } = string.Empty;
        private Dictionary<int, IMaterial>? _TeacherMaterials = null;
        [NotMapped]
        public Dictionary<int, IMaterial> TeacherMaterials {
            get
            {
                if (_TeacherMaterials == null)
                {
                    _TeacherMaterials = Materials
                            .ToDictionary(recPC => recPC.MaterialId, recPC => (recPC.Material as IMaterial));
                }
                return _TeacherMaterials;
            }
        } 

        public int Id { get; set; }
        [ForeignKey("TeacherId")]
        public virtual List<TeacherMaterial> Materials { get; set; } = new();
        [ForeignKey("TeacherId")]
        public virtual List<Task> Tasks { get; set; } = new();
        [ForeignKey("TeacherId")]
        public virtual List<Lesson> Lessons { get; set; } = new();
        public static Teacher Create(SchoolDataBase context, TeacherBindingModel model)
        {
            return new Teacher()
            {
                Id = model.Id,
                Name = model.Name,
                Post = model.Post,
                Phone = model.Phone,
                Login = model.Login,
                Password = model.Password,
                Materials = model.TeacherMaterials.Select(x => new TeacherMaterial
                {
                    Material = context.Materials.First(y => y.Id == x.Key),
                }).ToList()
            };
        }

        public void Update(TeacherBindingModel model)
        {
            Name = model.Name;
            Post = model.Post;
            Phone = model.Phone;
            Login = model.Login;
            Password = model.Password;
        }

        public TeacherViewModel GetViewModel => new()
        {
            Id = Id,
            Name = Name,
            Post = Post,
            Phone = Phone,
            Login = Login,
            Password = Password,
            TeacherMaterials = TeacherMaterials
        };

        public void UpdateMaterials(SchoolDataBase context, TeacherBindingModel model)
        {
            var teacherMaterials = context.TeacherMaterials.Where(rec => rec.TeacherId == model.Id).ToList();
            if (teacherMaterials != null && teacherMaterials.Count > 0)
            {
                context.TeacherMaterials.RemoveRange(teacherMaterials.Where(rec => !model.TeacherMaterials.ContainsKey(rec.MaterialId)));
                context.SaveChanges();

                foreach (var updateMaterial in teacherMaterials)
                {
                    model.TeacherMaterials.Remove(updateMaterial.MaterialId);
                }
                context.SaveChanges();
            }
            var teacher = context.Teachers.First(x => x.Id == Id);
            foreach (var pc in model.TeacherMaterials)
            {
                context.TeacherMaterials.Add(new TeacherMaterial
                {
                    Teacher = teacher,
                    Material = context.Materials.First(x => x.Id == pc.Key),
                });
                context.SaveChanges();
            }
            _TeacherMaterials = null;
        }
    }
}