// 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.IO;
using System.Security.Cryptography;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CSharp.UnitTests;
using Microsoft.CodeAnalysis.MetadataAsSource;
using Microsoft.CodeAnalysis.PdbSourceDocument;
using Roslyn.Test.Utilities;
using Xunit;

namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.PdbSourceDocument;

public sealed class PdbSourceDocumentLoaderServiceTests : AbstractPdbSourceDocumentTests
{
    [Fact]
    public Task ReturnsSourceFileFromSourceLink()
        => RunTestAsync(async path =>
        {
            MarkupTestFile.GetSpan("""
            public class C
            {
                public event System.EventHandler [|E|] { add { } remove { } }
            }
            """, out var metadataSource, out var expectedSpan);

            var (project, symbol) = await CompileAndFindSymbolAsync(path, Location.OnDisk, Location.OnDisk, metadataSource, c => c.GetMember("C.E"));

            // Move the source file to a path that only our fake debugger service knows about
            var sourceFilePath = Path.Combine(path, "SourceLink.cs");
            File.Move(GetSourceFilePath(path), sourceFilePath);

            var sourceLinkService = new TestSourceLinkService(sourceFilePath: sourceFilePath);
            var service = new PdbSourceDocumentLoaderService(logger: null);

            using var hash = SHA256.Create();
            var fileHash = hash.ComputeHash(File.ReadAllBytes(sourceFilePath));

            var sourceDocument = new SourceDocument("goo.cs", Text.SourceHashAlgorithms.Default, [.. fileHash], null, "https://sourcelink");
            var result = await service.LoadSourceDocumentAsync(path, sourceDocument, Encoding.UTF8, new TelemetryMessage(CancellationToken.None), useExtendedTimeout: false, sourceLinkService, CancellationToken.None);

            Assert.NotNull(result);
            Assert.Equal(sourceFilePath, result!.FilePath);
            Assert.True(result.FromRemoteLocation);
        });

    [Fact]
    public Task NoUrlFoundReturnsNull()
        => RunTestAsync(async path =>
        {
            MarkupTestFile.GetSpan("""
            public class C
            {
                public event System.EventHandler [|E|] { add { } remove { } }
            }
            """, out var metadataSource, out var expectedSpan);

            var (project, symbol) = await CompileAndFindSymbolAsync(path, Location.OnDisk, Location.OnDisk, metadataSource, c => c.GetMember("C.E"));

            // Move the source file to a path that only our fake debugger service knows about
            var sourceFilePath = Path.Combine(path, "SourceLink.cs");
            File.Move(GetSourceFilePath(path), sourceFilePath);

            var sourceLinkService = new TestSourceLinkService(sourceFilePath: sourceFilePath);
            var service = new PdbSourceDocumentLoaderService(logger: null);

            var sourceDocument = new SourceDocument("goo.cs", Text.SourceHashAlgorithm.None, default, null, SourceLinkUrl: null);
            var result = await service.LoadSourceDocumentAsync(path, sourceDocument, Encoding.UTF8, new TelemetryMessage(CancellationToken.None), useExtendedTimeout: false, sourceLinkService, CancellationToken.None);

            Assert.Null(result);
        });
}
