using Avalonia;
using Avalonia.Controls.ApplicationLifetimes;
using Avalonia.Media.Imaging;
using Avalonia.Platform.Storage;
using AvaloniaApplicationTestNew.Models;
using AvaloniaApplicationTestNew.Views;
using Microsoft.EntityFrameworkCore;
using ReactiveUI;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;

namespace AvaloniaApplicationTestNew.ViewModels
{
    public class UserPageViewModel : ViewModelBase
    {
        string message;
        User current_user;
        List<Gender> gendersList;
        Bitmap imageUser;
        bool isReadyToDelete = false;
        Trait selectTrait;
        Trait selectItem;
        List<Trait> withoutTraits;
        List<Trait> withTraits;

        public string Message { get => message; set => this.RaiseAndSetIfChanged(ref message, value); }
        public User Current_user { get => current_user; set => current_user = value; }
        public List<Gender> GendersList { get => gendersList; set => gendersList = value; }
        public Bitmap ImageUser { get => imageUser; set => this.RaiseAndSetIfChanged(ref imageUser, value); }
        public Trait SelectTrait { get => selectTrait; set => this.RaiseAndSetIfChanged(ref selectTrait, value); }
        public Trait SelectItem { get => selectItem; set => this.RaiseAndSetIfChanged(ref selectItem, value); }
        public List<Trait> WithoutTraits { get => withoutTraits; set => this.RaiseAndSetIfChanged(ref withoutTraits, value); }
        public List<Trait> WithTraits { get => withTraits; set => this.RaiseAndSetIfChanged(ref withTraits, value); }
        public bool IsReadyToDelete { get => isReadyToDelete; set => this.RaiseAndSetIfChanged(ref isReadyToDelete, value); }

        public UserPageViewModel(int id) 
        {
            Current_user = myContext.Users.Include(x => x.IdTraits).Include(x => x.IdGenderNavigation).FirstOrDefault(x => x.IdUser == id);
            GendersList = myContext.Genders.ToList();
            imageUser = Current_user.Image != null ? new Bitmap(new MemoryStream(Current_user.Image)) : new Bitmap("Assets\\ava.png");
            WithoutTraits = myContext.Traits.ToList().Except(Current_user.IdTraits).ToList();
            WithTraits = Current_user.IdTraits.ToList();
        }
        public void SaveAndChange()
        {
            if (string.IsNullOrWhiteSpace(Current_user.Name) || Current_user.IdGenderNavigation == null || Current_user.BirthDate == null)
            {
                Message = "Заполните все поля";
            }
            else if (DateTime.Today <= Current_user.BirthDate)
            {
                Message = "Пользователь родился в будущем? Исправьте дату";
                Current_user.BirthDate = null;
            }
            else
            {
                myContext.SaveChanges();
                Message = "Данные сохранены";
            }
        }
        public void Back()
        {
            MainWindowViewModel.Self.AuthorizationVM = new AuthorizationViewModel();
            MainWindowViewModel.Self.Page = new Authorization();
        }
        public async Task Image()
        {
            if(Application.Current?.ApplicationLifetime is not IClassicDesktopStyleApplicationLifetime desktop ||
                desktop.MainWindow?.StorageProvider is not { } provider) 
                throw new NullReferenceException("Missing StorageProvider instance.");
            var files = await provider.OpenFilePickerAsync(new FilePickerOpenOptions()
            {
                Title = "Выберите фото для аватарки",
                AllowMultiple = false
            });
            await using var readStream = await files[0].OpenReadAsync();
            byte[] buffer = new byte[1000000];
            var bytes = readStream.ReadAtLeast(buffer, 1);
            Array.Resize(ref buffer, bytes);
            Current_user.Image = buffer;
            ImageUser = new Bitmap(new MemoryStream(current_user.Image));
            myContext.SaveChanges();
            MainWindowViewModel.Self.UserPageVM = new UserPageViewModel(Current_user.IdUser);
            MainWindowViewModel.Self.Page = new UserPage();
        }
        public void DeleteImage()
        {
            MemoryStream stream = new MemoryStream();
            byte[] byteArray;
            ImageUser = new Bitmap("Assets\\ava.png");
            ImageUser.Save(stream);
            Current_user.Image = stream.ToArray();
            myContext.SaveChanges();
            MainWindowViewModel.Self.UserPageVM = new UserPageViewModel(Current_user.IdUser);
            MainWindowViewModel.Self.Page = new UserPage();
        }
        public void AddTrait()
        {
            if(SelectTrait != null)
            {
                Current_user.IdTraits.Add(SelectTrait);
                SaveAndChange();
                MainWindowViewModel.Self.UserPageVM = new UserPageViewModel(Current_user.IdUser);
                MainWindowViewModel.Self.Page = new UserPage();
            }
        }
        public void DeleteTrait()
        {
            if(SelectItem != null)
            {
                Current_user.IdTraits.Remove(SelectItem);
                SaveAndChange();
                MainWindowViewModel.Self.UserPageVM = new UserPageViewModel(Current_user.IdUser);
                MainWindowViewModel.Self.Page = new UserPage();
            }
            else
            {
                IsReadyToDelete = true;
            }
        }
    }
}