// 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.Composition;
using System.Diagnostics.CodeAnalysis;
using Microsoft.CodeAnalysis.CodeFixes;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.Shared.Extensions;
using Microsoft.CodeAnalysis.UseNullPropagation;
 
namespace Microsoft.CodeAnalysis.CSharp.UseNullPropagation
{
    [ExportCodeFixProvider(LanguageNames.CSharp, Name = PredefinedCodeFixProviderNames.UseNullPropagation), Shared]
    internal class CSharpUseNullPropagationCodeFixProvider : AbstractUseNullPropagationCodeFixProvider<
        SyntaxKind,
        ExpressionSyntax,
        StatementSyntax,
        ConditionalExpressionSyntax,
        BinaryExpressionSyntax,
        InvocationExpressionSyntax,
        ConditionalAccessExpressionSyntax,
        ElementAccessExpressionSyntax,
        MemberAccessExpressionSyntax,
        ElementBindingExpressionSyntax,
        IfStatementSyntax,
        ExpressionStatementSyntax,
        BracketedArgumentListSyntax>
    {
        [ImportingConstructor]
        [SuppressMessage("RoslynDiagnosticsReliability", "RS0033:Importing constructor should be [Obsolete]", Justification = "Used in test code: https://github.com/dotnet/roslyn/issues/42814")]
        public CSharpUseNullPropagationCodeFixProvider()
        {
        }
 
        protected override bool TryGetBlock(SyntaxNode? statement, [NotNullWhen(true)] out StatementSyntax? block)
        {
            if (statement is BlockSyntax statementBlock)
            {
                block = statementBlock;
                return true;
            }
 
            block = null;
            return false;
        }
 
        protected override StatementSyntax ReplaceBlockStatements(StatementSyntax block, StatementSyntax newInnerStatement)
        {
            var newStatementList = SyntaxFactory.SingletonList(newInnerStatement);
            return ((BlockSyntax)block).WithStatements(newStatementList);
        }
 
        protected override SyntaxNode PostProcessElseIf(IfStatementSyntax ifStatement, StatementSyntax newWhenTrueStatement)
        {
            var elseClauseSyntax = (ElseClauseSyntax)ifStatement.Parent!;
            return elseClauseSyntax
                .WithElseKeyword(elseClauseSyntax.ElseKeyword.WithTrailingTrivia())
                .WithStatement(newWhenTrueStatement.WithPrependedLeadingTrivia(ifStatement.CloseParenToken.TrailingTrivia));
        }
 
        protected override ElementBindingExpressionSyntax ElementBindingExpression(BracketedArgumentListSyntax argumentList)
            => SyntaxFactory.ElementBindingExpression(argumentList);
    }
}