// 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.Extensions;
using Microsoft.CodeAnalysis.Host.Mef;
using Roslyn.LanguageServer.Protocol;
 
namespace Microsoft.CodeAnalysis.LanguageServer.Handler.Extensions;
 
[ExportCSharpVisualBasicStatelessLspService(typeof(ExtensionDocumentMessageHandler)), Shared]
[Method(MethodName)]
[method: ImportingConstructor]
[method: Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
internal sealed class ExtensionDocumentMessageHandler()
    : AbstractExtensionHandler, ILspServiceDocumentRequestHandler<ExtensionDocumentMessageParams, ExtensionMessageResponse>
{
    private const string MethodName = "roslyn/extensionDocumentMessage";
 
    public TextDocumentIdentifier GetTextDocumentIdentifier(ExtensionDocumentMessageParams request)
        => request.TextDocument;
 
    public async Task<ExtensionMessageResponse> HandleRequestAsync(ExtensionDocumentMessageParams request, RequestContext context, CancellationToken cancellationToken)
    {
        Contract.ThrowIfNull(context.Document);
 
        var solution = context.Document.Project.Solution;
 
        var service = solution.Services.GetRequiredService<IExtensionMessageHandlerService>();
        var (response, extensionWasUnloaded, exception) = await service.HandleExtensionDocumentMessageAsync(
            context.Document, request.MessageName, request.Message, cancellationToken).ConfigureAwait(false);
 
        // Report any exceptions the extension itself caused while handling the request.
        if (exception is not null)
            context.Logger.LogException(exception);
 
        return new ExtensionMessageResponse(response, extensionWasUnloaded, exception);
    }
}