// 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.Collections.Immutable;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.EmbeddedLanguages.StackFrame;
using Microsoft.CodeAnalysis.LanguageService;
using Microsoft.CodeAnalysis.Shared.Extensions;

namespace Microsoft.CodeAnalysis.StackTraceExplorer;

internal sealed class StackFrameLocalMethodResolver : AbstractStackTraceSymbolResolver
{
    public override async Task<IMethodSymbol?> TryGetBestMatchAsync(
        Project project,
        INamedTypeSymbol type,
        StackFrameSimpleNameNode methodNode,
        StackFrameParameterList methodArguments,
        StackFrameTypeArgumentList? methodTypeArguments,
        CancellationToken cancellationToken)
    {
        if (methodNode is not StackFrameLocalMethodNameNode localMethodNameNode)
        {
            return null;
        }

        var compilation = await project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);
        if (compilation is null)
        {
            return null;
        }

        var containingMethodName = localMethodNameNode.EncapsulatingMethod.Identifier.ToString();
        var semanticFacts = project.GetRequiredLanguageService<ISemanticFactsService>();
        var candidateFunctions = type
            .GetMembers()
            .Where(member => member.Name == containingMethodName)
            .SelectMany(member => semanticFacts.GetLocalFunctionSymbols(compilation, member, cancellationToken));

        return TryGetBestMatch(candidateFunctions, methodTypeArguments, methodArguments);
    }
}