// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using System;
using System.Composition;
using Microsoft.CodeAnalysis.Editor.Shared.Extensions;
using Microsoft.CodeAnalysis.Editor.Shared.Utilities;
using Microsoft.CodeAnalysis.Host.Mef;
using Microsoft.CodeAnalysis.Shared.TestHooks;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Adornments;
using Microsoft.VisualStudio.Text.Editor;
 
namespace Microsoft.CodeAnalysis.Editor.BackgroundWorkIndicator;
 
[Export(typeof(WpfBackgroundWorkIndicatorFactory))]
[ExportWorkspaceService(typeof(IBackgroundWorkIndicatorFactory), ServiceLayer.Editor), Shared]
internal sealed partial class WpfBackgroundWorkIndicatorFactory : IBackgroundWorkIndicatorFactory
{
    private readonly IThreadingContext _threadingContext;
    private readonly IToolTipPresenterFactory _toolTipPresenterFactory;
    private readonly IAsynchronousOperationListener _listener;
 
    private BackgroundWorkIndicatorContext? _currentContext;
 
    [ImportingConstructor]
    [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
    public WpfBackgroundWorkIndicatorFactory(
        IThreadingContext threadingContext,
        IToolTipPresenterFactory toolTipPresenterFactory,
        IAsynchronousOperationListenerProvider listenerProvider)
    {
        _threadingContext = threadingContext;
        _toolTipPresenterFactory = toolTipPresenterFactory;
        _listener = listenerProvider.GetListener(FeatureAttribute.QuickInfo);
    }
 
    IBackgroundWorkIndicatorContext IBackgroundWorkIndicatorFactory.Create(
        ITextView textView,
        SnapshotSpan applicableToSpan,
        string description,
        bool cancelOnEdit,
        bool cancelOnFocusLost)
    {
        _threadingContext.ThrowIfNotOnUIThread();
 
        // If we have an outstanding context in flight, cancel it and create a new one to show the user.
        _currentContext?.CancelAndDispose();
 
        // Create the indicator in its default/empty state.
        _currentContext = new BackgroundWorkIndicatorContext(
            this, textView, applicableToSpan, description,
            cancelOnEdit, cancelOnFocusLost);
 
        // Then add a single scope representing the how the UI should look initially.
        _currentContext.AddScope(allowCancellation: true, description);
        return _currentContext;
    }
 
    private void OnContextDisposed(BackgroundWorkIndicatorContext context)
    {
        _threadingContext.ThrowIfNotOnUIThread();
 
        if (_currentContext == context)
            _currentContext = null;
    }
}