// 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.
 
#nullable disable
 
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Roslyn.Test.Utilities;
using Xunit;
using Xunit.Abstractions;
using LSP = Roslyn.LanguageServer.Protocol;
 
namespace Microsoft.CodeAnalysis.LanguageServer.UnitTests.References;
 
public sealed class FindImplementationsTests : AbstractLanguageServerProtocolTests
{
    public FindImplementationsTests(ITestOutputHelper testOutputHelper) : base(testOutputHelper)
    {
    }
 
    [Theory, CombinatorialData]
    public async Task TestFindImplementationAsync(bool mutatingLspWorkspace)
    {
        var markup =
@"interface IA
{
    void {|caret:|}M();
}
class A : IA
{
    void IA.{|implementation:M|}()
    {
    }
}";
        await using var testLspServer = await CreateTestLspServerAsync(markup, mutatingLspWorkspace);
 
        var results = await RunFindImplementationAsync(testLspServer, testLspServer.GetLocations("caret").Single());
        AssertLocationsEqual(testLspServer.GetLocations("implementation"), results);
    }
 
    [Theory, CombinatorialData]
    public async Task TestFindImplementationAsync_DifferentDocument(bool mutatingLspWorkspace)
    {
        var markups = new string[]
        {
@"namespace One
{
    interface IA
    {
        void {|caret:|}M();
    }
}",
@"namespace One
{
    class A : IA
    {
        void IA.{|implementation:M|}()
        {
        }
    }
}"
        };
 
        await using var testLspServer = await CreateTestLspServerAsync(markups, mutatingLspWorkspace);
 
        var results = await RunFindImplementationAsync(testLspServer, testLspServer.GetLocations("caret").Single());
        AssertLocationsEqual(testLspServer.GetLocations("implementation"), results);
    }
 
    [Theory, CombinatorialData]
    public async Task TestFindImplementationAsync_MappedFile(bool mutatingLspWorkspace)
    {
        var markup =
@"interface IA
{
    void M();
}
class A : IA
{
    void IA.M()
    {
    }
}";
        await using var testLspServer = await CreateTestLspServerAsync(string.Empty, mutatingLspWorkspace);
 
        AddMappedDocument(testLspServer.TestWorkspace, markup);
 
        var position = new LSP.Position { Line = 2, Character = 9 };
        var results = await RunFindImplementationAsync(testLspServer, new LSP.Location
        {
            Uri = ProtocolConversions.CreateAbsoluteUri($"C:\\{TestSpanMapper.GeneratedFileName}"),
            Range = new LSP.Range { Start = position, End = position }
        });
        AssertLocationsEqual([TestSpanMapper.MappedFileLocation], results);
    }
 
    [Theory, CombinatorialData]
    public async Task TestFindImplementationAsync_InvalidLocation(bool mutatingLspWorkspace)
    {
        var markup =
@"class A
{
    void M()
    {
        {|caret:|}
    }
}";
        await using var testLspServer = await CreateTestLspServerAsync(markup, mutatingLspWorkspace);
 
        var results = await RunFindImplementationAsync(testLspServer, testLspServer.GetLocations("caret").Single());
        Assert.Empty(results);
    }
 
    [Theory, CombinatorialData, WorkItem("https://github.com/dotnet/roslyn/issues/44846")]
    public async Task TestFindImplementationAsync_MultipleLocations(bool mutatingLspWorkspace)
    {
        var markup =
@"class {|caret:|}A { }
 
class {|implementation:B|} : A { }
 
class {|implementation:C|} : A { }";
        await using var testLspServer = await CreateTestLspServerAsync(markup, mutatingLspWorkspace);
 
        var results = await RunFindImplementationAsync(testLspServer, testLspServer.GetLocations("caret").Single());
        AssertLocationsEqual(testLspServer.GetLocations("implementation"), results);
    }
 
    [Theory, CombinatorialData]
    public async Task TestFindImplementationAsync_NoMetadataResults(bool mutatingLspWorkspace)
    {
        var markup = @"
using System;
class C : IDisposable
{
    public void {|implementation:Dispose|}()
    {
        IDisposable d;
        d.{|caret:|}Dispose();
    }
}";
        await using var testLspServer = await CreateTestLspServerAsync(markup, mutatingLspWorkspace);
 
        var results = await RunFindImplementationAsync(testLspServer, testLspServer.GetLocations("caret").Single());
 
        // At the moment we only support source results here, so verify we haven't accidentally
        // broken that without work to make sure they display nicely
        AssertLocationsEqual(testLspServer.GetLocations("implementation"), results);
    }
 
    private static async Task<LSP.Location[]> RunFindImplementationAsync(TestLspServer testLspServer, LSP.Location caret)
    {
        return await testLspServer.ExecuteRequestAsync<LSP.TextDocumentPositionParams, LSP.Location[]>(LSP.Methods.TextDocumentImplementationName,
                       CreateTextDocumentPositionParams(caret), CancellationToken.None);
    }
}