// 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.Collections.Generic;
using System.Collections.Immutable;
using System.Composition;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeRefactorings;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.ExtractInterface;
using Microsoft.CodeAnalysis.Host.Mef;
using Microsoft.CodeAnalysis.Shared.Extensions;
using Microsoft.CodeAnalysis.Text;

namespace Microsoft.CodeAnalysis.CSharp.ExtractInterface;

[ExportLanguageService(typeof(AbstractExtractInterfaceService), LanguageNames.CSharp), Shared]
internal sealed class CSharpExtractInterfaceService : AbstractExtractInterfaceService
{
    [ImportingConstructor]
    [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
    public CSharpExtractInterfaceService()
    {
    }

    protected override async Task<SyntaxNode> GetTypeDeclarationAsync(Document document, int position, TypeDiscoveryRule typeDiscoveryRule, CancellationToken cancellationToken)
    {
        var span = new TextSpan(position, 0);
        var typeDeclarationNode = await document.TryGetRelevantNodeAsync<TypeDeclarationSyntax>(span, cancellationToken).ConfigureAwait(false);

        // If TypeDiscoverRule is set to TypeDeclaration, a position anywhere inside of the
        // declaration enclosure is valid. In this case check to see if there is a type declaration ancestor
        // of the focused node.
        if (typeDeclarationNode == null && typeDiscoveryRule == TypeDiscoveryRule.TypeDeclaration)
        {
            var relevantNode = await document.TryGetRelevantNodeAsync<SyntaxNode>(span, cancellationToken).ConfigureAwait(false);
            return relevantNode.GetAncestor<TypeDeclarationSyntax>();
        }

        return typeDeclarationNode;

    }

    internal override string GetContainingNamespaceDisplay(INamedTypeSymbol typeSymbol, CompilationOptions compilationOptions)
    {
        return typeSymbol.ContainingNamespace.IsGlobalNamespace
            ? string.Empty
            : typeSymbol.ContainingNamespace.ToDisplayString();
    }

    internal override bool IsExtractableMember(ISymbol m)
        => base.IsExtractableMember(m) && !m.ExplicitInterfaceImplementations().Any();

    internal override bool ShouldIncludeAccessibilityModifier(SyntaxNode typeNode)
    {
        var typeDeclaration = typeNode as TypeDeclarationSyntax;
        return typeDeclaration.Modifiers.Any(m => SyntaxFacts.IsAccessibilityModifier(m.Kind()));
    }

    protected override Task<Solution> UpdateMembersWithExplicitImplementationsAsync(
        Solution unformattedSolution, IReadOnlyList<DocumentId> documentIds,
        INamedTypeSymbol extractedInterface, INamedTypeSymbol typeToExtractFrom,
        IEnumerable<ISymbol> includedMembers, ImmutableDictionary<ISymbol, SyntaxAnnotation> symbolToDeclarationMap,
        CancellationToken cancellationToken)
    {
        // In C#, member implementations do not always need
        // to be explicitly added. It's safe enough to return
        // the passed in solution
        return Task.FromResult(unformattedSolution);
    }
}