// 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.Collections.Immutable;
using System.Composition;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeRefactorings;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.ExtractClass;
using Microsoft.CodeAnalysis.Host.Mef;
 
namespace Microsoft.CodeAnalysis.CSharp.CodeRefactorings.ExtractClass
{
    [ExportCodeRefactoringProvider(LanguageNames.CSharp, Name = PredefinedCodeRefactoringProviderNames.ExtractClass), Shared]
    [ExtensionOrder(After = PredefinedCodeRefactoringProviderNames.ExtractInterface)]
    [ExtensionOrder(After = PredefinedCodeRefactoringProviderNames.UseExpressionBody)]
    internal class CSharpExtractClassCodeRefactoringProvider : AbstractExtractClassRefactoringProvider
    {
        [ImportingConstructor]
        [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
        public CSharpExtractClassCodeRefactoringProvider()
            : base(null)
        {
        }
 
        /// <summary>
        /// Test purpose only.
        /// </summary>
        [SuppressMessage("RoslynDiagnosticsReliability", "RS0034:Exported parts should have [ImportingConstructor]", Justification = "Used incorrectly by tests")]
        internal CSharpExtractClassCodeRefactoringProvider(IExtractClassOptionsService optionsService)
            : base(optionsService)
        {
        }
 
        protected override async Task<SyntaxNode?> GetSelectedClassDeclarationAsync(CodeRefactoringContext context)
        {
            var relaventNodes = await context.GetRelevantNodesAsync<ClassDeclarationSyntax>().ConfigureAwait(false);
            return relaventNodes.FirstOrDefault();
        }
 
        protected override Task<ImmutableArray<SyntaxNode>> GetSelectedNodesAsync(CodeRefactoringContext context)
            => NodeSelectionHelpers.GetSelectedDeclarationsOrVariablesAsync(context);
    }
}