// 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.Text;
using Microsoft.CommonLanguageServerProtocol.Framework;
using LSP = Roslyn.LanguageServer.Protocol;
 
namespace Microsoft.CodeAnalysis.LanguageServer.Handler.DocumentChanges;
 
[ExportCSharpVisualBasicStatelessLspService(typeof(DidOpenHandler)), Shared]
[Method(LSP.Methods.TextDocumentDidOpenName)]
internal class DidOpenHandler : ILspServiceNotificationHandler<LSP.DidOpenTextDocumentParams>, ITextDocumentIdentifierHandler<LSP.DidOpenTextDocumentParams, Uri>
{
    [ImportingConstructor]
    [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
    public DidOpenHandler()
    {
    }
 
    public bool MutatesSolutionState => true;
    public bool RequiresLSPSolution => false;
 
    public Uri GetTextDocumentIdentifier(LSP.DidOpenTextDocumentParams request) => request.TextDocument.Uri;
 
    public async Task HandleNotificationAsync(LSP.DidOpenTextDocumentParams request, RequestContext context, CancellationToken cancellationToken)
    {
        // GetTextDocumentIdentifier returns null to avoid creating the solution, so the queue is not able to log the uri.
        context.TraceInformation($"didOpen for {request.TextDocument.Uri}");
 
        // Add the document and ensure the text we have matches whats on the client
        // TODO (https://github.com/dotnet/roslyn/issues/63583):
        // Create SourceText from binary representation of the document, retrieve encoding from the request and checksum algorithm from the project.
        var sourceText = SourceText.From(request.TextDocument.Text, System.Text.Encoding.UTF8, SourceHashAlgorithms.OpenDocumentChecksumAlgorithm);
 
        await context.StartTrackingAsync(request.TextDocument.Uri, sourceText, request.TextDocument.LanguageId, cancellationToken).ConfigureAwait(false);
    }
}