// 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.Threading.Tasks;
using Roslyn.LanguageServer.Protocol;
using Xunit;
 
namespace Microsoft.CommonLanguageServerProtocol.Framework.UnitTests;
 
public partial class ExampleTests
{
    [Fact]
    public void InitializeServer_WithMethodRegisteredTwice_Fails()
    {
        // Arrange
        var logger = GetLogger();
 
        // Act
        var ex = Assert.Throws<InvalidOperationException>(() => TestExampleLanguageServer.CreateBadLanguageServer(logger));
 
        Assert.Equal("Method textDocument/didOpen was implemented more than once.", ex.Message);
    }
 
    [Fact]
    public async Task InitializeServer_WithMultipleHandlerRegistration_Succeeds()
    {
        // Arrange
        var logger = GetLogger();
        var server = TestExampleLanguageServer.CreateLanguageServer(logger);
 
        // Act
        // Verifying that this does not throw.
        var _ = await server.InitializeServerAsync();
 
        // Assert
        var handlerProvider = server.GetTestAccessor().GetQueueAccessor()!.Value.GetHandlerProvider();
        var methods = handlerProvider.GetRegisteredMethods();
 
        Assert.Equal(5, methods.Length);
        Assert.Contains(methods, m => m.MethodName == Methods.TextDocumentDidCloseName);
        Assert.Contains(methods, m => m.MethodName == Methods.InitializeName);
        Assert.Contains(methods, m => m.MethodName == Methods.TextDocumentDidOpenName);
        Assert.Contains(methods, m => m.MethodName == Methods.InitializedName);
        Assert.Contains(methods, m => m.MethodName == Methods.TextDocumentDidChangeName);
    }
 
    [Fact]
    public async Task InitializeServer_SerializesCorrectly()
    {
        var logger = GetLogger();
        var server = TestExampleLanguageServer.CreateLanguageServer(logger);
 
        var result = await server.InitializeServerAsync();
        Assert.True(result.Capabilities.SemanticTokensOptions!.Value.Unify().Range!.Value.First);
    }
 
    [Fact]
    public async Task ShutdownServer_Succeeds()
    {
        var logger = GetLogger();
        var server = TestExampleLanguageServer.CreateLanguageServer(logger);
 
        _ = await server.InitializeServerAsync();
 
        await server.ShutdownServerAsync();
 
        var result = await server.WaitForShutdown();
        Assert.True(0 == result, "Server failed to shut down properly");
    }
 
    private static ILspLogger GetLogger()
    {
        return NoOpLspLogger.Instance;
    }
}