Partially fix Base4K encoding

Author: d2dyno1

src/Core/SecureFolderFS.Core.FileSystem/Helpers/Paths/Abstract/AbstractPathHelpers.Cipher.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -161,7 +162,22 @@ public static async Task<string> EncryptNameAsync(string plaintextName, IFolder
                 var directoryId = AllocateDirectoryId(specifics.Security, ciphertextName);
                 var result = await GetDirectoryIdAsync(ciphertextParentFolder, specifics, directoryId, cancellationToken);
 
-                return specifics.Security.NameCrypt.DecryptName(Path.GetFileNameWithoutExtension(ciphertextName), result ? directoryId : ReadOnlySpan<byte>.Empty);
+                // Do NOT use Path.GetFileNameWithoutExtension - after APFS or ContentProvider NFD-decomposes Base4K
+                // codepoints, the string may contain spurious dot-like characters that confuse the
+                // path parser, causing it to truncate mid-ciphertext.
+                // Strip the known extension manually instead.
+                var nameWithoutExtension = ciphertextName.EndsWith(Constants.Names.ENCRYPTED_FILE_EXTENSION, StringComparison.Ordinal)
+                    ? ciphertextName.AsSpan(0, ciphertextName.Length - Constants.Names.ENCRYPTED_FILE_EXTENSION.Length)
+                    : ciphertextName.AsSpan();
+
+                var normalizedLength = nameWithoutExtension.GetNormalizedLength(NormalizationForm.FormC);
+                var normalized = new char[normalizedLength];
+
+                // NFC-normalize before decoding
+                if (nameWithoutExtension.TryNormalize(normalized, out var written, NormalizationForm.FormC))
+                    return specifics.Security.NameCrypt.DecryptName(normalized.AsSpan(0, written), result ? directoryId : ReadOnlySpan<byte>.Empty);
+
+                return specifics.Security.NameCrypt.DecryptName(nameWithoutExtension, result ? directoryId : ReadOnlySpan<byte>.Empty);
             }
             catch (Exception)
             {

src/Core/SecureFolderFS.Core.FileSystem/Validators/BaseFileSystemValidator.cs

@@ -57,22 +57,15 @@ protected async Task<IResult> ValidateNameResultAsync(IStorableChild storable, C
             if (parentFolder is null)
                 return null;
 
-            var ciphertextName = storable.Name;
-            var directoryId = AbstractPathHelpers.AllocateDirectoryId(specifics.Security, ciphertextName);
+            var decryptedName = await AbstractPathHelpers.DecryptNameAsync(storable.Name, parentFolder, specifics, cancellationToken);
+            if (!string.IsNullOrEmpty(decryptedName))
+                return decryptedName;
 
-            try
-            {
-                var result = await AbstractPathHelpers.GetDirectoryIdAsync(parentFolder, specifics, directoryId, cancellationToken).ConfigureAwait(false);
-                return specifics.Security.NameCrypt.DecryptName(Path.GetFileNameWithoutExtension(ciphertextName), result ? directoryId : ReadOnlySpan<byte>.Empty);
-            }
-            catch (FileNotFoundException)
-            {
-                // We want to suppress FileNotFoundException that might be raised when the DirectoryID file is not found.
-                // This case should be already handled in the folder validator
+            // We want to suppress failures that might be raised when the Directory ID file is not found.
+            // This case should be already handled in the folder validator
 
-                // Return an empty string to prevent raising exceptions due to the name being null
-                return string.Empty;
-            }
+            // Return an empty string to prevent raising exceptions due to the name being null
+            return string.Empty;
         }
     }
 }

src/Platforms/SecureFolderFS.Maui/Views/Modals/DeviceLink/DeviceLinkCredentialsPage.xaml

@@ -33,7 +33,7 @@
                 Background="{StaticResource ThemePrimaryColorBrush}">
                 <Border
                     Padding="20"
-                    Background="{StaticResource ThemeSecondaryColorBrush}"
+                    Background="{StaticResource ThemeElevatedFillPrimaryColorBrush}"
                     StrokeThickness="0">
                     <Border.StrokeShape>
                         <RoundRectangle CornerRadius="16" />
@@ -140,14 +140,12 @@
                             <Label
                                 FontAttributes="Bold"
                                 FontSize="18"
-                                Text="{l:ResourceString Rid=DeviceLink}"
-                                TextColor="{StaticResource PrimaryContrastingLightColor}" />
+                                Text="{l:ResourceString Rid=DeviceLink}" />
                             <Label
                                 FontSize="13"
                                 LineBreakMode="WordWrap"
                                 Opacity="0.8"
-                                Text="{l:ResourceString Rid=DeviceLinkDescription}"
-                                TextColor="{StaticResource PrimaryContrastingLightColor}" />
+                                Text="{l:ResourceString Rid=DeviceLinkDescription}" />
                         </VerticalStackLayout>
                     </Grid>
                 </Border>

src/Platforms/SecureFolderFS.Maui/Views/Modals/Settings/SettingsPage.xaml

@@ -30,7 +30,7 @@
                     Background="{StaticResource ThemePrimaryColorBrush}">
                     <Border
                         Padding="20,20"
-                        Background="{StaticResource ThemeSecondaryColorBrush}"
+                        Background="{StaticResource ThemeElevatedFillPrimaryColorBrush}"
                         StrokeThickness="0">
                         <Border.StrokeShape>
                             <RoundRectangle CornerRadius="16" />
@@ -66,15 +66,13 @@
                                 FontAttributes="Bold"
                                 FontSize="18"
                                 HorizontalOptions="Center"
-                                Text="{l:ResourceString Rid=Settings}"
-                                TextColor="{StaticResource PrimaryContrastingLightColor}" />
+                                Text="{l:ResourceString Rid=Settings}" />
                             <Label
                                 FontSize="13"
                                 HorizontalOptions="Center"
                                 HorizontalTextAlignment="Center"
                                 Opacity="0.7"
-                                Text="Manage your preferences, appearance, and privacy options for SecureFolderFS."
-                                TextColor="{StaticResource PrimaryContrastingLightColor}" />
+                                Text="Manage your preferences, appearance, and privacy options for SecureFolderFS." />
                         </VerticalStackLayout>
                     </Border>
                 </Grid>

src/Platforms/SecureFolderFS.UI/ServiceImplementation/BaseVaultCredentialsService.cs

@@ -13,9 +13,7 @@ public abstract class BaseVaultCredentialsService : IVaultCredentialsService
         /// <inheritdoc/>
         public virtual IEnumerable<string> GetEncodingOptions()
         {
-            if (!OperatingSystem.IsIOS() && !OperatingSystem.IsMacOS() && !OperatingSystem.IsMacCatalyst() && !OperatingSystem.IsAndroid())
-                yield return Core.Cryptography.Constants.CipherId.ENCODING_BASE4K;
-
+            yield return Core.Cryptography.Constants.CipherId.ENCODING_BASE4K;
             yield return Core.Cryptography.Constants.CipherId.ENCODING_BASE64URL;
         }
 

src/Sdk/SecureFolderFS.Sdk/AppModels/ThumbnailCacheModel.cs

@@ -118,7 +118,6 @@ public static async Task<string> GetCacheKeyAsync(IFile file, CancellationToken
             if (dateModified is null)
                 return pathHash;
 
-
             // Combine path hash with modification date for the cache key
             // Format: {pathHash}_{dateModifiedTicks}
             return $"{pathHash}_{dateModified.Value.Ticks}";