ExperimentalViewModel.cs

using Files.Shared.Extensions;
using Files.App.Helpers;
using Files.Backend.Services.Settings;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.DependencyInjection;
using CommunityToolkit.Mvvm.Input;
using System;
using System.Threading.Tasks;
using System.Windows.Input;
using Windows.ApplicationModel;
using Windows.Foundation.Collections;
using Windows.Storage;
using Windows.System;
using Files.App.Shell;
using System.IO;
using System.Diagnostics;
using Microsoft.Win32;

namespace Files.App.ViewModels.SettingsViewModels
{
    public class ExperimentalViewModel : ObservableObject
    {
        private IUserSettingsService UserSettingsService { get; } = Ioc.Default.GetService<IUserSettingsService>();

        public ICommand EditFileTagsCommand { get; }

        public ICommand SetAsDefaultExplorerCommand { get; }

        public ICommand SetAsOpenFileDialogCommand { get; }

        public ExperimentalViewModel()
        {
            IsSetAsDefaultFileManager = DetectIsSetAsDefaultFileManager();
            IsSetAsOpenFileDialog = DetectIsSetAsOpenFileDialog();

            EditFileTagsCommand = new AsyncRelayCommand(LaunchFileTagsConfigFile);
            SetAsDefaultExplorerCommand = new AsyncRelayCommand(SetAsDefaultExplorer);
            SetAsOpenFileDialogCommand = new AsyncRelayCommand(SetAsOpenFileDialog);
        }

        public bool ShowFolderSize
        {
            get => UserSettingsService.PreferencesSettingsService.ShowFolderSize;
            set
            {
                if (value != UserSettingsService.PreferencesSettingsService.ShowFolderSize)
                {
                    UserSettingsService.PreferencesSettingsService.ShowFolderSize = value;
                    OnPropertyChanged();
                }
            }
        }

        private async Task LaunchFileTagsConfigFile()
        {
            var configFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appdata:///local/settings/filetags.json"));
            if (!await Launcher.LaunchFileAsync(configFile))
            {
                await ContextMenu.InvokeVerb("open", configFile.Path);
            }
        }

        private async Task SetAsDefaultExplorer()
        {
            if (IsSetAsDefaultFileManager == DetectIsSetAsDefaultFileManager())
            {
                return;
            }

            var destFolder = Path.Combine(ApplicationData.Current.LocalFolder.Path, "FilesOpenDialog");
            Directory.CreateDirectory(destFolder);
            foreach (var file in Directory.GetFiles(Path.Combine(Package.Current.InstalledLocation.Path, "Files.FullTrust", "Assets", "FilesOpenDialog")))
            {
                if (!SafetyExtensions.IgnoreExceptions(() => File.Copy(file, Path.Combine(destFolder, Path.GetFileName(file)), true), App.Logger))
                {
                    // Error copying files
                    goto DetectResult;
                }
            }

            var dataPath = Environment.ExpandEnvironmentVariables("%LocalAppData%\\Files");
            if (IsSetAsDefaultFileManager)
            {
                if (!Win32API.RunPowershellCommand($"-command \"New-Item -Force -Path '{dataPath}' -ItemType Directory; Copy-Item -Filter *.* -Path '{destFolder}\\*' -Recurse -Force -Destination '{dataPath}'\"", false))
                {
                    // Error copying files
                    goto DetectResult;
                }
            }
            else
            {
                Win32API.RunPowershellCommand($"-command \"Remove-Item -Path '{dataPath}' -Recurse -Force\"", false);
            }

            try
            {
                using var regProcess = Process.Start(new ProcessStartInfo("regedit.exe", @$"/s ""{Path.Combine(destFolder, IsSetAsDefaultFileManager ? "SetFilesAsDefault.reg" : "UnsetFilesAsDefault.reg")}""") { UseShellExecute = true, Verb = "runas" });
                await regProcess.WaitForExitAsync();
            }
            catch
            {
                // Canceled UAC
            }

        DetectResult:
            IsSetAsDefaultFileManager = DetectIsSetAsDefaultFileManager();
            if (!IsSetAsDefaultFileManager)
            {
                IsSetAsOpenFileDialog = false;
                await SetAsOpenFileDialog();
            }
        }

        private async Task SetAsOpenFileDialog()
        {
            if (IsSetAsOpenFileDialog == DetectIsSetAsOpenFileDialog())
            {
                return;
            }

            var destFolder = Path.Combine(ApplicationData.Current.LocalFolder.Path, "FilesOpenDialog");
            Directory.CreateDirectory(destFolder);
            foreach (var file in Directory.GetFiles(Path.Combine(Package.Current.InstalledLocation.Path, "Files.FullTrust", "Assets", "FilesOpenDialog")))
            {
                if (!SafetyExtensions.IgnoreExceptions(() => File.Copy(file, Path.Combine(destFolder, Path.GetFileName(file)), true), App.Logger))
                {
                    // Error copying files
                    goto DetectResult;
                }
            }

            try
            {
                using var regProc32 = Process.Start("regsvr32.exe", @$"/s /n {(!IsSetAsOpenFileDialog ? "/u" : "")} /i:user ""{Path.Combine(destFolder, "CustomOpenDialog32.dll")}""");
                await regProc32.WaitForExitAsync();
                using var regProc64 = Process.Start("regsvr32.exe", @$"/s /n {(!IsSetAsOpenFileDialog ? "/u" : "")} /i:user ""{Path.Combine(destFolder, "CustomOpenDialog64.dll")}""");
                await regProc64.WaitForExitAsync();
                using var regProcARM64 = Process.Start("regsvr32.exe", @$"/s /n {(!IsSetAsOpenFileDialog ? "/u" : "")} /i:user ""{Path.Combine(destFolder, "CustomOpenDialogARM64.dll")}""");
                await regProcARM64.WaitForExitAsync();
            }
            catch
            {
            }

        DetectResult:
            IsSetAsOpenFileDialog = DetectIsSetAsOpenFileDialog();
        }

        private bool DetectIsSetAsDefaultFileManager()
        {
            using var subkey = Registry.ClassesRoot.OpenSubKey(@"Folder\shell\open\command");
            var command = (string?)subkey?.GetValue(string.Empty);
            return !string.IsNullOrEmpty(command) && command.Contains("FilesLauncher.exe");
        }

        private bool DetectIsSetAsOpenFileDialog()
        {
            using var subkey = Registry.CurrentUser.OpenSubKey(@"SOFTWARE\Classes\CLSID\{DC1C5A9C-E88A-4DDE-A5A1-60F82A20AEF7}");
            return subkey?.GetValue(string.Empty) as string == "FilesOpenDialog class";
        }

        private bool isSetAsDefaultFileManager;

        public bool IsSetAsDefaultFileManager
        {
            get => isSetAsDefaultFileManager;
            set => SetProperty(ref isSetAsDefaultFileManager, value);
        }

        private bool isSetAsOpenFileDialog;

        public bool IsSetAsOpenFileDialog
        {
            get => isSetAsOpenFileDialog;
            set => SetProperty(ref isSetAsOpenFileDialog, value);
        }
    }
}