---

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows.Input;

namespace GuessGameApp.ViewModels
{
    public class MainViewModel : INotifyPropertyChanged
    {
        private static readonly Random _random = new();

        public List<int> DifficultyLevels { get; } = new() { 3, 4, 5, 6 };

        private int _selectedDifficulty = 3;
        public int SelectedDifficulty
        {
            get => _selectedDifficulty;
            set
            {
                if (_selectedDifficulty != value)
                {
                    _selectedDifficulty = value;
                    OnPropertyChanged();
                    GenerateNewCode();
                }
            }
        }

        private string _secretCode = string.Empty;
        public string SecretCode
        {
            get => _secretCode;
            private set
            {
                _secretCode = value;
                OnPropertyChanged();
            }
        }

        private string _userInput = string.Empty;
        public string UserInput
        {
            get => _userInput;
            set
            {
                _userInput = value;
                OnPropertyChanged();
            }
        }

        private string _statusMessage = string.Empty;
        public string StatusMessage
        {
            get => _statusMessage;
            private set
            {
                _statusMessage = value;
                OnPropertyChanged();
            }
        }

        public ICommand CheckGuessCommand { get; }

        public MainViewModel()
        {
            CheckGuessCommand = new RelayCommand(CheckGuess);
            GenerateNewCode();
        }

        private void GenerateNewCode()
        {
            char[] digits = new char[SelectedDifficulty];
            for (int i = 0; i < SelectedDifficulty; i++)
            {
                digits[i] = (char)('0' + _random.Next(0, 10));
            }
            SecretCode = new string(digits);
            StatusMessage = $"Загадано число из {SelectedDifficulty} цифр";
            UserInput = string.Empty;
        }

        private void CheckGuess()
        {
            if (string.IsNullOrWhiteSpace(UserInput))
            {
                StatusMessage = "Введите число!";
                return;
            }

            if (UserInput == SecretCode)
            {
                StatusMessage = "Угадано! Новая игра...";
                GenerateNewCode();
            }
            else
            {
                StatusMessage = "Неверно, попробуйте еще раз!";
            }
        }

        public event PropertyChangedEventHandler? PropertyChanged;
        protected void OnPropertyChanged([CallerMemberName] string? name = null)
            => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
    }

    // Простая реализация ICommand для кнопки
    public class RelayCommand : ICommand
    {
        private readonly Action _execute;
        public RelayCommand(Action execute) => _execute = execute;
        public bool CanExecute(object? parameter) => true;
        public void Execute(object? parameter) => _execute();
        public event EventHandler? CanExecuteChanged { add { } remove { } }
    }
}