Add FolderProvider

Toolkit.Foundation/FileFilter.cs

@@ -1,3 +1,3 @@
 namespace Toolkit.Foundation;
 
-public record FileFilter(string Name, List<string> Extensions, bool AllowMultiple = false);
+public record FileFilter(string Name, List<string> Extensions, bool AllowMultiple = false);

Toolkit.Foundation/FolderFilter.cs

@@ -0,0 +1,3 @@
+namespace Toolkit.Foundation;
+
+public record FolderFilter(bool AllowMultiple = false);

Toolkit.Foundation/IFolderProvider.cs

@@ -0,0 +1,6 @@
+namespace Toolkit.Foundation;
+
+public interface IFolderProvider
+{
+    Task<IReadOnlyCollection<string>> SelectFolders(FolderFilter filter);
+}

Toolkit.Foundation/Result.cs

@@ -12,3 +12,22 @@ public record Result<TValue> :
 
     public static implicit operator Result<TValue>(TValue? value) => Create(value);
 }
+
+
+public record Result(bool IsSuccess, Error Error)
+{
+    public bool IsFailure => !IsSuccess;
+
+    public static Result Success() => new(true, Error.None);
+
+    public static Result<TValue> Success<TValue>(TValue value) => new(value, true, Error.None);
+
+    public static Result Failure(Error error) => new(false, error);
+
+    public static Result<TValue> Failure<TValue>(Error error) => new(default, false, error);
+
+    public static Result Create(bool condition) => condition ? Success() : Failure(Error.ConditionNotMet);
+
+    public static Result<TValue> Create<TValue>(TValue? value) => value is not null ? Success(value) : Failure<TValue>(Error.Null);
+
+}

Toolkit.Foundation/Result1.cs

@@ -1,19 +0,0 @@
-namespace Toolkit.Foundation;
-
-public record Result(bool IsSuccess, Error Error)
-{
-    public bool IsFailure => !IsSuccess;
-
-    public static Result Success() => new(true, Error.None);
-
-    public static Result<TValue> Success<TValue>(TValue value) => new(value, true, Error.None);
-
-    public static Result Failure(Error error) => new(false, error);
-
-    public static Result<TValue> Failure<TValue>(Error error) => new(default, false, error);
-
-    public static Result Create(bool condition) => condition ? Success() : Failure(Error.ConditionNotMet);
-
-    public static Result<TValue> Create<TValue>(TValue? value) => value is not null ? Success(value) : Failure<TValue>(Error.Null);
-
-}

Toolkit.Foundation/SelectFoldersHandler.cs

@@ -0,0 +1,20 @@
+namespace Toolkit.Foundation;
+
+public class SelectFoldersHandler(IFolderProvider folderProvider) :
+    IHandler<SelectionEventArgs<FolderFilter>, IReadOnlyCollection<string>?>
+{
+    public async Task<IReadOnlyCollection<string>?> Handle(SelectionEventArgs<FolderFilter> args, 
+        CancellationToken cancellationToken)
+    {
+        if (args.Sender is FolderFilter filter)
+        {
+            if (await folderProvider.SelectFolders(filter)
+                is { Count: > 0 } folders)
+            {
+                return folders;
+            }
+        }
+
+        return default;
+    }
+}