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.Diagnostics;
using System.Linq;
using System.Runtime.ConstrainedExecution;
using System.Text;
using System.Threading.Tasks;

namespace SchoolAgainStudyDataBaseImplements.Models
{
    public class Student : IStudent
    {
        [Required]
        public string Name { get; set; } = string.Empty;
        [Required]
        public int Class { get; set; }
        [Required]
        public string Email { get; set; } = string.Empty;
        [Required]
        public string Login { get; set; } = string.Empty;
        [Required]
        public string Password { get; set; } = string.Empty;

        private Dictionary<int, IInterest>? _StudentInterests = null;
        [NotMapped]
        public Dictionary<int, IInterest> StudentInterests 
        {
            get
            {
                if (_StudentInterests == null)
                {
                    _StudentInterests = Interests
                            .ToDictionary(recPC => recPC.InterestId, recPC => (recPC.Interest as IInterest));
                }
                return _StudentInterests;
            } 
        }

        public int Id { get; set; }

        [ForeignKey("StudentId")]
        public virtual List<StudentInterest> Interests { get; set; } = new();
        [ForeignKey("StudentId")]
        public virtual List<Diy> Diys { get; set; } = new();
        [ForeignKey("StudentId")]
        public virtual List<Product> Products { get; set; } = new();
        public static Student Create(SchoolDataBase context, StudentBindingModel model)
        {
            return new Student()
            {
                Id = model.Id,
                Name = model.Name,
                Class = model.Class,
                Email = model.Email,
                Login = model.Login,
                Password = model.Password,
                Interests = model.StudentInterests.Select(x => new StudentInterest
                {
                    Interest = context.Interests.First(y => y.Id == x.Key),
                }).ToList()
            };
        }

        public void Update(StudentBindingModel model)
        {
            Name = model.Name;
            Class = model.Class;
            Email = model.Email;
            Login = model.Login;
            Password = model.Password;
        }

        public StudentViewModel GetViewModel => new()
        {
            Id = Id,
            Name = Name,
            Class = Class,
            Email = Email,
            Login = Login,
            Password = Password,
            StudentInterests = StudentInterests
        };

        public void UpdateInterests(SchoolDataBase context, StudentBindingModel model)
        {
            var studentInterests = context.StudentInterests.Where(rec => rec.StudentId == model.Id).ToList();
            if (studentInterests != null && studentInterests.Count > 0)
            {
                context.StudentInterests.RemoveRange(studentInterests.Where(rec => !model.StudentInterests.ContainsKey(rec.InterestId)));
                context.SaveChanges();

                foreach (var updateInterest in studentInterests)
                {
                    model.StudentInterests.Remove(updateInterest.InterestId);
                }
                context.SaveChanges();
            }
            var student = context.Students.First(x => x.Id == Id);
            foreach (var pc in model.StudentInterests)
            {
                context.StudentInterests.Add(new StudentInterest
                {
                    Student = student,
                    Interest = context.Interests.First(x => x.Id == pc.Key),
            });
                context.SaveChanges();
            }
            _StudentInterests = null;
        }
    }
}