Add a warning about missing CDM keys before starting downloads

OF DL.Core/Models/Config/Config.cs

@@ -92,6 +92,8 @@ public class Config : IFileNameFormatConfig
     [JsonConverter(typeof(StringEnumConverter))]
     public Theme Theme { get; set; } = Theme.light;
 
+    [ToggleableConfig] public bool HideMissingCdmKeysWarning { get; set; }
+
     [ToggleableConfig] public bool IgnoreOwnMessages { get; set; }
 
     [ToggleableConfig] public bool DisableBrowserAuth { get; set; }

OF DL.Core/Services/ConfigService.cs

@@ -238,6 +238,9 @@ public class ConfigService(ILoggingService loggingService) : IConfigService
 
                 // Appearance Settings
                 Theme = ParseTheme(hoconConfig.GetString("Appearance.Theme", "light")),
+                HideMissingCdmKeysWarning =
+                    bool.TryParse(hoconConfig.GetString("Appearance.HideMissingCdmKeysWarning", "false"),
+                        out bool hideMissingCdmKeysWarning) && hideMissingCdmKeysWarning,
 
                 // Logging/Debug Settings
                 LoggingLevel = Enum.Parse<LoggingLevel>(hoconConfig.GetString("Logging.LoggingLevel"), true)
@@ -413,6 +416,7 @@ public class ConfigService(ILoggingService loggingService) : IConfigService
         hocon.AppendLine("# Appearance Settings");
         hocon.AppendLine("Appearance {");
         hocon.AppendLine($"  Theme = \"{config.Theme.ToString().ToLower()}\"");
+        hocon.AppendLine($"  HideMissingCdmKeysWarning = {config.HideMissingCdmKeysWarning.ToString().ToLower()}");
         hocon.AppendLine("}");
 
         hocon.AppendLine("# Logging/Debug Settings");

OF DL.Gui/ViewModels/ConfigFieldViewModel.cs

@@ -57,7 +57,8 @@ public partial class ConfigFieldViewModel : ViewModelBase
             [nameof(Config.IgnoredUsersListName)] = "Ignored Users List",
             [nameof(Config.RenameExistingFilesWhenCustomFormatIsSelected)] =
                 "Rename Existing Files with Custom Formats",
-            [nameof(Config.DownloadPath)] = "Download Folder"
+            [nameof(Config.DownloadPath)] = "Download Folder",
+            [nameof(Config.HideMissingCdmKeysWarning)] = "Hide Missing CDM Keys Warning"
         };
 
     public ConfigFieldViewModel(

OF DL.Gui/ViewModels/MainWindowViewModel.cs

@@ -40,6 +40,7 @@ public partial class MainWindowViewModel(
         long? UserId);
 
     private const string UnknownToolVersion = "Not detected";
+
     private static readonly Regex s_singlePostUrlRegex = new(
         @"^https://onlyfans\.com/(?<postId>\d+)/(?<username>[A-Za-z0-9_.-]+)/?$",
         RegexOptions.Compiled | RegexOptions.IgnoreCase);
@@ -154,6 +155,8 @@ public partial class MainWindowViewModel(
             "Download rate limit in MB/s when rate limiting is enabled.",
         [nameof(Config.Theme)] =
             "GUI theme for the configuration and download screens.",
+        [nameof(Config.HideMissingCdmKeysWarning)] =
+            "Hide the missing CDM keys warning before downloads start.",
         [nameof(Config.LoggingLevel)] =
             "Log verbosity written to logs/OFDL.txt."
     };
@@ -319,14 +322,23 @@ public partial class MainWindowViewModel(
     [ObservableProperty]
     [NotifyCanExecuteChangedFor(nameof(OpenSinglePostOrMessageModalCommand))]
     [NotifyCanExecuteChangedFor(nameof(SubmitSinglePostOrMessageCommand))]
+    [NotifyCanExecuteChangedFor(nameof(DownloadSelectedCommand))]
+    [NotifyCanExecuteChangedFor(nameof(DownloadPurchasedTabCommand))]
     private bool _isSinglePostOrMessageModalOpen;
 
     [ObservableProperty]
+    [NotifyCanExecuteChangedFor(nameof(OpenSinglePostOrMessageModalCommand))]
     [NotifyCanExecuteChangedFor(nameof(SubmitSinglePostOrMessageCommand))]
+    [NotifyCanExecuteChangedFor(nameof(DownloadSelectedCommand))]
+    [NotifyCanExecuteChangedFor(nameof(DownloadPurchasedTabCommand))]
+    private bool _isMissingCdmWarningModalOpen;
+
+    [ObservableProperty] private string _missingCdmWarningMessage = string.Empty;
+
+    [ObservableProperty] [NotifyCanExecuteChangedFor(nameof(SubmitSinglePostOrMessageCommand))]
     private string _singlePostOrMessageUrl = string.Empty;
 
-    [ObservableProperty]
+    [ObservableProperty] [NotifyPropertyChangedFor(nameof(HasSinglePostOrMessageUrlError))]
-    [NotifyPropertyChangedFor(nameof(HasSinglePostOrMessageUrlError))]
     private string _singlePostOrMessageUrlError = string.Empty;
 
     public bool IsLoadingScreen => CurrentScreen == AppScreen.Loading;
@@ -432,6 +444,7 @@ public partial class MainWindowViewModel(
     }
 
     private bool _isUpdatingAllUsersSelected;
+    private TaskCompletionSource<bool>? _missingCdmWarningCompletionSource;
 
     public async Task InitializeAsync()
     {
@@ -752,6 +765,20 @@ public partial class MainWindowViewModel(
         IsSinglePostOrMessageModalOpen = false;
     }
 
+    [RelayCommand]
+    private void ConfirmMissingCdmWarning()
+    {
+        IsMissingCdmWarningModalOpen = false;
+        _missingCdmWarningCompletionSource?.TrySetResult(true);
+    }
+
+    [RelayCommand]
+    private void CancelMissingCdmWarning()
+    {
+        IsMissingCdmWarningModalOpen = false;
+        _missingCdmWarningCompletionSource?.TrySetResult(false);
+    }
+
     [RelayCommand(CanExecute = nameof(CanStopWork))]
     private void StopWork()
     {
@@ -779,6 +806,11 @@ public partial class MainWindowViewModel(
             return;
         }
 
+        if (!await EnsureMissingCdmWarningConfirmedAsync())
+        {
+            return;
+        }
+
         IsDownloading = true;
         _workCancellationSource?.Dispose();
         _workCancellationSource = new CancellationTokenSource();
@@ -871,20 +903,24 @@ public partial class MainWindowViewModel(
     private bool CanDownloadSelected() =>
         CurrentScreen == AppScreen.UserSelection &&
         AvailableUsers.Any(user => user.IsSelected) &&
+        !IsMissingCdmWarningModalOpen &&
         !IsDownloading;
 
     private bool CanDownloadPurchasedTab() =>
         CurrentScreen == AppScreen.UserSelection &&
         _allUsers.Count > 0 &&
+        !IsMissingCdmWarningModalOpen &&
         !IsDownloading;
 
     private bool CanOpenSinglePostOrMessageModal() =>
         CurrentScreen == AppScreen.UserSelection &&
         !IsDownloading &&
+        !IsMissingCdmWarningModalOpen &&
         !IsSinglePostOrMessageModalOpen;
 
     private bool CanSubmitSinglePostOrMessage() =>
         IsSinglePostOrMessageModalOpen &&
+        !IsMissingCdmWarningModalOpen &&
         !IsDownloading &&
         !string.IsNullOrWhiteSpace(SinglePostOrMessageUrl);
 
@@ -951,10 +987,7 @@ public partial class MainWindowViewModel(
         _ = SelectUsersFromListAsync();
     }
 
-    partial void OnSinglePostOrMessageUrlChanged(string value)
+    partial void OnSinglePostOrMessageUrlChanged(string value) => SinglePostOrMessageUrlError = string.Empty;
-    {
-        SinglePostOrMessageUrlError = string.Empty;
-    }
 
     partial void OnFfmpegPathChanged(string value)
     {
@@ -1024,6 +1057,11 @@ public partial class MainWindowViewModel(
             return;
         }
 
+        if (!await EnsureMissingCdmWarningConfirmedAsync())
+        {
+            return;
+        }
+
         IsDownloading = true;
         _workCancellationSource?.Dispose();
         _workCancellationSource = new CancellationTokenSource();
@@ -1134,6 +1172,55 @@ public partial class MainWindowViewModel(
         }
     }
 
+    private async Task<bool> EnsureMissingCdmWarningConfirmedAsync()
+    {
+        bool hasMissingCdmKeys = _startupResult.ClientIdBlobMissing || _startupResult.DevicePrivateKeyMissing;
+        if (!hasMissingCdmKeys || configService.CurrentConfig.HideMissingCdmKeysWarning)
+        {
+            return true;
+        }
+
+        List<string> missingFiles = [];
+        if (_startupResult.ClientIdBlobMissing)
+        {
+            missingFiles.Add("device_client_id_blob");
+        }
+
+        if (_startupResult.DevicePrivateKeyMissing)
+        {
+            missingFiles.Add("device_private_key");
+        }
+
+        string missingSummary = string.Join(" and ", missingFiles);
+        MissingCdmWarningMessage =
+            $"Missing CDM key file(s): {missingSummary}\n\n" +
+            "CDM keys are recommended to decrypt DRM-protected videos. Without these keys, the application will use a fallback online decryption service, which may be slower and less reliable.\n\n" +
+            "You can hide this warning in the future by enabling \"Hide Missing CDM Keys Warning\" in the configuration settings.\n\n";
+
+        _missingCdmWarningCompletionSource =
+            new TaskCompletionSource<bool>(TaskCreationOptions.RunContinuationsAsynchronously);
+        IsMissingCdmWarningModalOpen = true;
+
+        bool confirmed;
+        try
+        {
+            confirmed = await _missingCdmWarningCompletionSource.Task;
+        }
+        finally
+        {
+            _missingCdmWarningCompletionSource = null;
+            IsMissingCdmWarningModalOpen = false;
+        }
+
+        if (!confirmed)
+        {
+            StatusMessage = "Download canceled.";
+            AppendLog("Download canceled after missing CDM keys warning.");
+        }
+
+        return confirmed;
+    }
+
     private static bool TryParseSinglePostOrMessageUrl(
         string url,
         out SingleDownloadRequest request,
@@ -1254,7 +1341,7 @@ public partial class MainWindowViewModel(
         if (_startupResult.ClientIdBlobMissing || _startupResult.DevicePrivateKeyMissing)
         {
             AppendLog(
-                "Widevine device files are missing. Fallback decrypt services will be used for DRM protected videos.");
+                "CDM key files are missing. Fallback decrypt services will be used for DRM protected videos.");
         }
 
         return true;
@@ -1472,9 +1559,10 @@ public partial class MainWindowViewModel(
         List<ConfigCategoryViewModel> orderedCategories = [];
         foreach (IGrouping<string, ConfigFieldViewModel> group in grouped)
         {
-            IEnumerable<ConfigFieldViewModel> orderedFields = group.Key is "File Naming" or "Download Behavior"
+            IEnumerable<ConfigFieldViewModel> orderedFields =
-                ? group.OrderBy(field => GetFieldOrder(group.Key, field.PropertyName))
+                group.Key is "File Naming" or "Download Behavior" or "Appearance"
-                : group.OrderBy(field => field.DisplayName);
+                    ? group.OrderBy(field => GetFieldOrder(group.Key, field.PropertyName))
+                    : group.OrderBy(field => field.DisplayName);
 
             ConfigCategoryViewModel category = new(group.Key, orderedFields);
             orderedCategories.Add(category);
@@ -1534,6 +1622,16 @@ public partial class MainWindowViewModel(
             };
         }
 
+        if (categoryName == "Appearance")
+        {
+            return propertyName switch
+            {
+                nameof(Config.Theme) => 0,
+                nameof(Config.HideMissingCdmKeysWarning) => 1,
+                _ => 100
+            };
+        }
+
         return 0;
     }
 
@@ -1882,10 +1980,7 @@ public partial class MainWindowViewModel(
         return JsonConvert.DeserializeObject<Config>(json) ?? new Config();
     }
 
-    private static void EnforceGuiOnlyConfigValues(Config config)
+    private static void EnforceGuiOnlyConfigValues(Config config) => config.ShowScrapeSize = false;
-    {
-        config.ShowScrapeSize = false;
-    }
 
     private static bool IsHiddenConfigField(string propertyName) =>
         propertyName is nameof(Config.NonInteractiveMode)
@@ -1962,6 +2057,7 @@ public partial class MainWindowViewModel(
             nameof(Config.DownloadLimitInMbPerSec) => "Performance",
 
             nameof(Config.Theme) => "Appearance",
+            nameof(Config.HideMissingCdmKeysWarning) => "Appearance",
 
             nameof(Config.LoggingLevel) => "Logging",
 

OF DL.Gui/Views/MainWindow.axaml

@@ -1442,5 +1442,43 @@
                 </ScrollViewer>
             </Border>
         </Grid>
+
+        <Grid Grid.Row="0" Grid.RowSpan="3"
+              IsVisible="{Binding IsMissingCdmWarningModalOpen}"
+              Background="{DynamicResource OverlayBackgroundBrush}"
+              ZIndex="1002"
+              PointerPressed="OnModalOverlayClicked">
+            <Border Background="{DynamicResource ModalBackgroundBrush}"
+                    BorderBrush="{DynamicResource ModalBorderBrush}"
+                    BorderThickness="1"
+                    CornerRadius="16"
+                    Padding="28"
+                    Width="680"
+                    MaxHeight="500"
+                    HorizontalAlignment="Center"
+                    VerticalAlignment="Center"
+                    BoxShadow="0 20 25 -5 #19000000, 0 10 10 -5 #0F000000"
+                    PointerPressed="OnModalContentClicked">
+                <StackPanel Spacing="16">
+                    <TextBlock FontSize="20"
+                               FontWeight="Bold"
+                               Foreground="{DynamicResource TextPrimaryBrush}"
+                               Text="Missing CDM Keys" />
+
+                    <TextBlock Foreground="{DynamicResource TextSecondaryBrush}"
+                               TextWrapping="Wrap"
+                               Text="{Binding MissingCdmWarningMessage}" />
+
+                    <StackPanel Orientation="Horizontal" Spacing="10" HorizontalAlignment="Right">
+                        <Button Content="Cancel"
+                                Classes="secondary"
+                                Command="{Binding CancelMissingCdmWarningCommand}" />
+                        <Button Content="Continue Download"
+                                Classes="primary"
+                                Command="{Binding ConfirmMissingCdmWarningCommand}" />
+                    </StackPanel>
+                </StackPanel>
+            </Border>
+        </Grid>
     </Grid>
 </Window>

OF DL.Gui/Views/MainWindow.axaml.cs

@@ -186,6 +186,7 @@ public partial class MainWindow : Window
         // Execute cancel command on any open modal
         vm.CreatorConfigEditor.ModalViewModel?.CancelCommand?.Execute(null);
         vm.CancelSinglePostOrMessageCommand.Execute(null);
+        vm.CancelMissingCdmWarningCommand.Execute(null);
     }
 
     private void OnModalContentClicked(object? sender, PointerPressedEventArgs e) =>

OF DL.Tests/Services/ConfigServiceTests.cs

@@ -24,6 +24,7 @@ public class ConfigServiceTests
         Assert.Equal("", service.CurrentConfig.FFprobePath);
         Assert.Equal(0.98, service.CurrentConfig.DrmVideoDurationMatchThreshold, 3);
         Assert.Equal(Theme.light, service.CurrentConfig.Theme);
+        Assert.False(service.CurrentConfig.HideMissingCdmKeysWarning);
     }
 
     [Fact]
@@ -100,6 +101,25 @@ public class ConfigServiceTests
         Assert.Equal(Theme.dark, service.CurrentConfig.Theme);
     }
 
+    [Fact]
+    public async Task LoadConfigurationAsync_ParsesHideMissingCdmKeysWarning()
+    {
+        using TempFolder temp = new();
+        using CurrentDirectoryScope _ = new(temp.Path);
+        FakeLoggingService loggingService = new();
+        ConfigService service = new(loggingService);
+        await service.SaveConfigurationAsync();
+
+        string hocon = await File.ReadAllTextAsync("config.conf");
+        hocon = hocon.Replace("HideMissingCdmKeysWarning = false", "HideMissingCdmKeysWarning = true");
+        await File.WriteAllTextAsync("config.conf", hocon);
+
+        bool result = await service.LoadConfigurationAsync([]);
+
+        Assert.True(result);
+        Assert.True(service.CurrentConfig.HideMissingCdmKeysWarning);
+    }
+
     [Fact]
     public void ApplyToggleableSelections_UpdatesConfigAndReturnsChange()
     {

docs/config/all-configuration-options.md

@@ -387,6 +387,18 @@ Allowed values: `true`, `false`
 Description: A folder will be created for each post (containing all the media for that post) if set to `true`.
 When set to `false`, post media will be downloaded into the `Posts/Free` folder.
 
+## HideMissingCdmKeysWarning
+
+Type: `boolean`
+
+Default: `false`
+
+Allowed values: `true`, `false`
+
+Description: If set to `false`, OF-DL will show a warning and ask for confirmation before starting downloads when
+`device_client_id_blob` and/or `device_private_key` is missing.
+If set to `true`, this warning is hidden and downloads start immediately.
+
 ## IgnoreOwnMessages
 
 Type: `boolean`

docs/config/configuration.md

@@ -70,6 +70,7 @@ information about what it does, its default value, and the allowed values.
 
 - Appearance
     - [Theme](/config/all-configuration-options#theme)
+    - [HideMissingCdmKeysWarning](/config/all-configuration-options#hidemissingcdmkeyswarning)
 
 - Logging
     - [LoggingLevel](/config/all-configuration-options#logginglevel)