// 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;
using System.IO;
using System.Reflection.Metadata;
using System.Reflection.Metadata.Ecma335;
using Microsoft.CodeAnalysis.CSharp.Test.Utilities;
using Microsoft.CodeAnalysis.Debugging;
using Microsoft.CodeAnalysis.Emit;
using Microsoft.CodeAnalysis.Test.Utilities;
using Microsoft.CodeAnalysis.Text;
using Microsoft.CodeAnalysis.UnitTests;
using Microsoft.DiaSymReader;
using Microsoft.DiaSymReader.PortablePdb;
using Moq;
using Roslyn.Test.Utilities;
using Xunit;
 
namespace Microsoft.CodeAnalysis.EditAndContinue.UnitTests;
 
public sealed class EditAndContinueMethodDebugInfoReaderTests
{
    private sealed class DummyMetadataImportProvider : IMetadataImportProvider
    {
        public object GetMetadataImport() => throw new NotImplementedException();
    }
 
    [Fact]
    public void Create_Errors()
    {
        Assert.Throws<ArgumentNullException>(() => EditAndContinueMethodDebugInfoReader.Create((ISymUnmanagedReader5)null));
        Assert.Throws<ArgumentNullException>(() => EditAndContinueMethodDebugInfoReader.Create((MetadataReader)null));
        Assert.Throws<ArgumentNullException>(() => EditAndContinueMethodDebugInfoReader.Create(null, 1));
 
        var mockSymReader = new Mock<ISymUnmanagedReader5>(MockBehavior.Strict).Object;
        Assert.Throws<ArgumentOutOfRangeException>(() => EditAndContinueMethodDebugInfoReader.Create(mockSymReader, 0));
        Assert.Throws<ArgumentOutOfRangeException>(() => EditAndContinueMethodDebugInfoReader.Create(mockSymReader, -1));
    }
 
    [Theory]
    [InlineData(DebugInformationFormat.PortablePdb, true)]
    [InlineData(DebugInformationFormat.PortablePdb, false)]
    [InlineData(DebugInformationFormat.Pdb, true)]
    public void DebugInfo(DebugInformationFormat format, bool useSymReader)
    {
        var source = @"
using System;
delegate void D();
class C
{
    public static void Main()
    {
        int x = 1;
        D d = () => Console.Write(x);
        d();
    }
}
";
        var tree = CSharpTestSource.Parse(source, path: "/a/c.cs", options: TestOptions.Regular.WithNoRefSafetyRulesAttribute(), checksumAlgorithm: SourceHashAlgorithm.Sha1);
        var compilation = CSharpTestBase.CreateCompilationWithMscorlib40AndSystemCore(tree, options: TestOptions.DebugDll);
 
        var pdbStream = new MemoryStream();
        compilation.EmitToArray(new EmitOptions(debugInformationFormat: format), pdbStream: pdbStream);
        pdbStream.Position = 0;
 
        DebugInformationReaderProvider provider;
        EditAndContinueMethodDebugInfoReader reader;
 
        if (format == DebugInformationFormat.PortablePdb && useSymReader)
        {
            var pdbStreamCom = SymUnmanagedStreamFactory.CreateStream(pdbStream);
            var metadataImportProvider = new DummyMetadataImportProvider();
            Assert.Equal(0, new SymBinder().GetReaderFromPdbStream(metadataImportProvider, pdbStreamCom, out var symReader));
            reader = EditAndContinueMethodDebugInfoReader.Create((ISymUnmanagedReader5)symReader, version: 1);
        }
        else
        {
            provider = DebugInformationReaderProvider.CreateFromStream(pdbStream);
            reader = provider.CreateEditAndContinueMethodDebugInfoReader();
        }
 
        // Main method
        var debugInfo = reader.GetDebugInfo(MetadataTokens.MethodDefinitionHandle(5));
        Assert.Equal(0, debugInfo.GetMethodOrdinal());
        AssertEx.Equal(["Offset=0 Ordinal=0 Kind=LambdaDisplayClass", "Offset=33 Ordinal=0 Kind=UserDefined"], debugInfo.InspectLocalSlots());
        AssertEx.Equal(["Offset=43 Id=0#0 Closure=0"], debugInfo.InspectLambdas());
        AssertEx.Equal(["Offset=0 Id=0#0"], debugInfo.InspectClosures());
 
        var localSig = reader.GetLocalSignature(MetadataTokens.MethodDefinitionHandle(5));
        Assert.Equal(MetadataTokens.StandaloneSignatureHandle(1), localSig);
 
        // method without debug information:
        debugInfo = reader.GetDebugInfo(MetadataTokens.MethodDefinitionHandle(1));
        Assert.Equal(-1, debugInfo.GetMethodOrdinal());
        Assert.Null(debugInfo.InspectLocalSlots());
        Assert.Null(debugInfo.InspectLambdas());
        Assert.Null(debugInfo.InspectClosures());
 
        localSig = reader.GetLocalSignature(MetadataTokens.MethodDefinitionHandle(1));
        Assert.Equal(default, localSig);
 
        // document checksums:
        Assert.False(reader.TryGetDocumentChecksum("/b/c.cs", out _, out _));
        Assert.False(reader.TryGetDocumentChecksum("/a/d.cs", out _, out _));
        Assert.False(reader.TryGetDocumentChecksum("/A/C.cs", out _, out _));
 
        Assert.True(reader.TryGetDocumentChecksum("/a/c.cs", out var actualChecksum, out var actualAlgorithm));
        Assert.Equal("21-C8-B2-D7-A3-6B-49-C7-57-DF-67-B8-1F-75-DF-6A-64-FD-59-22", BitConverter.ToString([.. actualChecksum]));
        Assert.Equal(new Guid("ff1816ec-aa5e-4d10-87f7-6f4963833460"), actualAlgorithm);
    }
}