// 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 System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.Host.Mef;
using Microsoft.CodeAnalysis.LanguageServer.Handler;
 
namespace Microsoft.CodeAnalysis.LanguageServer.UnitTests.RequestOrdering
{
    [ExportCSharpVisualBasicStatelessLspService(typeof(NonMutatingRequestHandler)), PartNotDiscoverable, Shared]
    [Method(MethodName)]
    internal class NonMutatingRequestHandler : ILspServiceRequestHandler<TestRequest, TestResponse>
    {
        public const string MethodName = nameof(NonMutatingRequestHandler);
        private const int Delay = 100;
 
        [ImportingConstructor]
        [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
        public NonMutatingRequestHandler()
        {
        }
 
        public bool MutatesSolutionState => false;
        public bool RequiresLSPSolution => true;
 
        public async Task<TestResponse> HandleRequestAsync(TestRequest request, RequestContext context, CancellationToken cancellationToken)
        {
            var response = new TestResponse();
 
            response.ContextHasSolution = context.Solution != null;
            response.StartTime = DateTime.UtcNow;
 
            await Task.Delay(Delay, cancellationToken).ConfigureAwait(false);
 
            // some busy work
            response.ToString();
 
            await Task.Delay(Delay, cancellationToken).ConfigureAwait(false);
 
            response.EndTime = DateTime.UtcNow;
 
            return response;
        }
    }
}