using System.Security.Cryptography;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;

namespace JJServiceManager
{
    /// <summary>
    /// 위험 작업 확인창: 무작위 숫자 6자리를 보여주고, 그 숫자를 정확히 입력해야만 확인됨
    /// (Windows 강제종료 / Windows 재시작)
    /// </summary>
    public sealed class CodeConfirmWindow : Window
    {
        private readonly string _code;
        private readonly TextBox _input;
        private readonly Button _ok;
        private readonly TextBlock _hint;

        public CodeConfirmWindow(string title, string message, string actionText)
        {
            _code = RandomNumberGenerator.GetInt32(0, 1_000_000).ToString("D6");

            Title = title;
            Width = 440;
            SizeToContent = SizeToContent.Height;
            ResizeMode = ResizeMode.NoResize;
            WindowStartupLocation = WindowStartupLocation.CenterOwner;
            ShowInTaskbar = false;
            Topmost = true;
            FontFamily = new FontFamily("Malgun Gothic");
            FontSize = 13;
            Background = Brushes2.Make("#FAFAFA");
            AppIcon.Apply(this);

            var root = new StackPanel { Margin = new Thickness(20, 18, 20, 16) };

            // 경고 문구
            root.Children.Add(new TextBlock
            {
                Text = "⚠ " + message,
                TextWrapping = TextWrapping.Wrap,
                Foreground = Brushes2.Make("#B71C1C"),
                FontWeight = FontWeights.SemiBold,
                Margin = new Thickness(0, 0, 0, 14)
            });

            root.Children.Add(new TextBlock
            {
                Text = "계속하려면 아래 숫자 6자리를 그대로 입력하세요.",
                Foreground = Brushes2.Make("#455A64"),
                Margin = new Thickness(0, 0, 0, 8)
            });

            // 무작위 숫자 (복사할 수 없는 글자로 표시)
            var codeBox = new Border
            {
                Background = Brushes2.Make("#FFF8E1"),
                BorderBrush = Brushes2.Make("#FFB300"),
                BorderThickness = new Thickness(1),
                CornerRadius = new CornerRadius(4),
                Padding = new Thickness(0, 8, 0, 8),
                Margin = new Thickness(0, 0, 0, 12),
                Child = new TextBlock
                {
                    Text = string.Join("  ", _code.ToCharArray()),
                    FontFamily = new FontFamily("Consolas"),
                    FontSize = 30,
                    FontWeight = FontWeights.Bold,
                    Foreground = Brushes2.Make("#E65100"),
                    HorizontalAlignment = HorizontalAlignment.Center,
                    IsHitTestVisible = false
                }
            };
            root.Children.Add(codeBox);

            // 입력칸 (숫자만, 붙여넣기 불가)
            _input = new TextBox
            {
                MaxLength = 6,
                FontFamily = new FontFamily("Consolas"),
                FontSize = 24,
                Height = 42,
                HorizontalContentAlignment = HorizontalAlignment.Center,
                VerticalContentAlignment = VerticalAlignment.Center,
                ToolTip = "위의 숫자 6자리를 입력"
            };
            InputMethod.SetIsInputMethodEnabled(_input, false);
            _input.PreviewTextInput += (s, e) =>
            {
                foreach (var c in e.Text)
                    if (c < '0' || c > '9') { e.Handled = true; return; }
            };
            DataObject.AddPastingHandler(_input, (s, e) => e.CancelCommand());
            _input.TextChanged += (s, e) => UpdateState();
            root.Children.Add(_input);

            _hint = new TextBlock
            {
                Text = " ",
                Foreground = Brushes2.Make("#C62828"),
                Margin = new Thickness(0, 6, 0, 0),
                HorizontalAlignment = HorizontalAlignment.Center
            };
            root.Children.Add(_hint);

            // 버튼
            var buttons = new StackPanel
            {
                Orientation = Orientation.Horizontal,
                HorizontalAlignment = HorizontalAlignment.Right,
                Margin = new Thickness(0, 10, 0, 0)
            };
            _ok = new Button { Content = actionText, IsEnabled = false, MinWidth = 110 };
            _ok.SetResourceReference(StyleProperty, "DangerButton");
            _ok.Click += (s, e) => Submit();
            var cancel = new Button { Content = "취소", MinWidth = 80, IsCancel = true };
            buttons.Children.Add(_ok);
            buttons.Children.Add(cancel);
            root.Children.Add(buttons);

            Content = root;

            Loaded += (s, e) => _input.Focus();
            PreviewKeyDown += (s, e) =>
            {
                if (e.Key == Key.Enter)
                {
                    e.Handled = true;
                    Submit();
                }
            };
        }

        private void UpdateState()
        {
            var t = _input.Text;
            _ok.IsEnabled = t == _code;
            if (t.Length == 6 && t != _code) _hint.Text = "숫자가 다릅니다. 다시 입력하세요.";
            else _hint.Text = " ";
        }

        private void Submit()
        {
            if (_input.Text == _code)
            {
                DialogResult = true;
            }
            else
            {
                _hint.Text = _input.Text.Length == 0 ? "숫자를 입력하세요." : "숫자가 다릅니다. 다시 입력하세요.";
                _input.SelectAll();
                _input.Focus();
            }
        }

        /// <summary>확인창을 띄우고, 숫자를 정확히 입력해 확인했으면 true</summary>
        public static bool Ask(Window owner, string title, string message, string actionText)
        {
            var w = new CodeConfirmWindow(title, message, actionText);
            if (owner != null && owner.IsVisible) w.Owner = owner;
            else w.WindowStartupLocation = WindowStartupLocation.CenterScreen;
            return w.ShowDialog() == true;
        }
    }
}