// 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.Diagnostics.CodeAnalysis;
using System.Threading;
using System.Threading.Tasks;
using Roslyn.Utilities;
 
namespace Microsoft.CodeAnalysis.Shared.TestHooks
{
    internal static partial class TaskExtensions
    {
        [SuppressMessage("Style", "VSTHRD200:Use \"Async\" suffix for async methods", Justification = "This is a Task wrapper, not an asynchronous method.")]
        public static Task CompletesAsyncOperation(this Task task, IAsyncToken asyncToken)
        {
            if (asyncToken is AsynchronousOperationListener.DiagnosticAsyncToken diagnosticToken)
            {
                diagnosticToken.AssociateWithTask(task);
            }
 
            return task.CompletesTrackingOperation(asyncToken);
        }
 
        [PerformanceSensitive(
            "https://developercommunity.visualstudio.com/content/problem/854696/changing-target-framework-takes-10-minutes-with-10.html",
            AllowCaptures = false)]
        [SuppressMessage("Style", "VSTHRD200:Use \"Async\" suffix for async methods", Justification = "This is a Task wrapper, not an asynchronous method.")]
        public static Task CompletesTrackingOperation(this Task task, IDisposable token)
        {
            if (token == null || token == EmptyAsyncToken.Instance)
            {
                return task;
            }
 
            return CompletesTrackingOperationSlow(task, token);
 
            static Task CompletesTrackingOperationSlow(Task task, IDisposable token)
            {
                return task.SafeContinueWith(
                    t => token.Dispose(),
                    CancellationToken.None,
                    TaskContinuationOptions.ExecuteSynchronously,
                    TaskScheduler.Default);
            }
        }
    }
}