#region Apache License 2.0
/*
Nuclex Foundation libraries for .NET
Copyright (C) 2002-2026 Markus Ewald / Nuclex Development Labs

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#endregion // Apache License 2.0

using System;

using Nuclex.Avalonia.Commands;

namespace Nuclex.Avalonia.ViewModels {

  /// <summary>Interface for view models that can switch between different pages</summary>
  /// <typeparam name="TPageEnumeration">
  ///   Type by which pages can be indicated (typically an enum)
  /// </typeparam>
  public interface IMultiPageViewModel<TPageEnumeration>
    where TPageEnumeration : struct {

    /// <summary>Command to switch the active tool page</summary>
    IAsyncCommand<TPageEnumeration> SwitchPageCommand { get; }

    /// <summary>The currently displayed page</summary>
    TPageEnumeration? ActivePage { get; }

    /// <summary>View model for the page that is currently being shown</summary>
    object? ActivePageViewModel { get; }

  }

} // namespace Nuclex.Avalonia.ViewModels