MossyUpdater/MainWindow.xaml.cs

using System;
using System.IO;
using System.Net.Http;
using System.Threading.Tasks;
using System.Windows;
using Ookii.Dialogs.Wpf;     // ← add this

namespace MossyUpdater
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void Browse_Click(object sender, RoutedEventArgs e)
        {
            var dlg = new VistaFolderBrowserDialog
            {
                Description = "Select a destination folder",
                UseDescriptionForTitle = true
            };

            // ShowDialog returns true if the user clicked OK
            if (dlg.ShowDialog() == true)
                FolderTextBox.Text = dlg.SelectedPath;
        }

        private async void Download_Click(object sender, RoutedEventArgs e)
        {
            string url = UrlTextBox.Text.Trim();
            string folder = FolderTextBox.Text.Trim();
            string filename = FilenameTextBox.Text.Trim();

            if (string.IsNullOrEmpty(url)
             || string.IsNullOrEmpty(folder)
             || string.IsNullOrEmpty(filename))
            {
                StatusTextBlock.Text = "Please fill in all fields.";
                StatusTextBlock.Foreground = System.Windows.Media.Brushes.Red;
                return;
            }

            string fullPath = Path.Combine(folder, filename);

            try
            {
                using var client = new HttpClient();
                var data = await client.GetByteArrayAsync(url);
                await File.WriteAllBytesAsync(fullPath, data);

                UnblockFile(fullPath);

                StatusTextBlock.Text = $"Downloaded and unblocked:\n{fullPath}";
                StatusTextBlock.Foreground = System.Windows.Media.Brushes.Green;
            }
            catch (Exception ex)
            {
                StatusTextBlock.Text = $"Error: {ex.Message}";
                StatusTextBlock.Foreground = System.Windows.Media.Brushes.Red;
            }
        }

        private void UnblockFile(string path)
        {
            var zone = path + ":Zone.Identifier";
            if (File.Exists(zone))
                File.Delete(zone);
        }
    }
}