Compression

src/Core/FileTime.Core.Abstraction/ContentAccess/IContentReader.cs

@@ -7,4 +7,5 @@ public interface IContentReader : IDisposable
 
     Task<byte[]> ReadBytesAsync(int bufferSize, int? offset = null);
     void SetPosition(long position);
+    Stream AsStream();
 }

src/Core/FileTime.Core.Abstraction/ContentAccess/IContentWriter.cs

@@ -6,4 +6,5 @@ public interface IContentWriter : IDisposable
 
     Task WriteBytesAsync(byte[] data, int? index = null, CancellationToken cancellationToken = default);
     Task FlushAsync(CancellationToken cancellationToken = default);
+    Stream AsStream();
 }

src/Core/FileTime.Core.Abstraction/Interactions/IOptionsInputElement.cs

@@ -3,5 +3,5 @@ namespace FileTime.Core.Interactions;
 public interface IOptionsInputElement : IInputElement
 {
     object Value { get; set; }
-    IEnumerable<IOptionElement> Options { get; }
+    IReadOnlyCollection<IOptionElement> Options { get; }
 }

src/Core/FileTime.Core.Abstraction/Interactions/OptionsInputElement.cs

@@ -5,19 +5,30 @@ namespace FileTime.Core.Interactions;
 
 public partial class OptionsInputElement<T> : InputElementBase, IOptionsInputElement, INotifyPropertyChanged
 {
-    public IEnumerable<OptionElement<T>> Options { get; }
+    public IReadOnlyCollection<OptionElement<T>> Options { get; }
 
     [Notify] private T? _value;
 
-    IEnumerable<IOptionElement> IOptionsInputElement.Options => Options;
+    IReadOnlyCollection<IOptionElement> IOptionsInputElement.Options => Options;
+
     object? IOptionsInputElement.Value
     {
-        get => Value;
-        set => Value = (T?)value;
+        get => Options.FirstOrDefault(o => o.Value?.Equals(_value) ?? false);
+        set
+        {
+            if (value is T newValue)
+            {
+                Value = newValue;
+            }
+            else if (value is OptionElement<T> optionElement)
+            {
+                Value = optionElement.Value;
+            }
+        }
     }
 
     public OptionsInputElement(string label, IEnumerable<OptionElement<T>> options) : base(label, InputType.Options)
     {
-        Options = options;
+        Options = options.ToList();
     }
 }

src/Core/FileTime.Core.Command/Copy/CopyCommand.cs

@@ -33,11 +33,15 @@ public class CopyCommand : CommandBase, ITransportationCommand
         ITimelessContentProvider timelessContentProvider,
         ICommandSchedulerNotifier commandSchedulerNotifier,
         ILogger<CopyCommand> logger,
-        IReadOnlyCollection<FullName>? sources,
-        TransportMode? mode,
-        FullName? targetFullName)
+        IReadOnlyCollection<FullName> sources,
+        TransportMode mode,
+        FullName targetFullName)
         : base("Copy - Calculating...")
     {
+        ArgumentNullException.ThrowIfNull(sources);
+        ArgumentNullException.ThrowIfNull(mode);
+        ArgumentNullException.ThrowIfNull(targetFullName);
+        
         _timelessContentProvider = timelessContentProvider;
         _commandSchedulerNotifier = commandSchedulerNotifier;
         _logger = logger;
@@ -54,12 +58,8 @@ public class CopyCommand : CommandBase, ITransportationCommand
             .Switch()
             .Subscribe(SetCurrentProgress);
 
-        if (sources is null) throw new ArgumentException(nameof(Sources) + " can not be null");
-        if (targetFullName is null) throw new ArgumentException(nameof(Target) + " can not be null");
-        if (mode is null) throw new ArgumentException(nameof(TransportMode) + " can not be null");
-
         Sources = new List<FullName>(sources).AsReadOnly();
-        TransportMode = mode.Value;
+        TransportMode = mode;
         Target = targetFullName;
 
         var recentSpeed = DeclarativePropertyHelpers.CombineLatest(