// 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 Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.Formatting.Rules;
 
namespace Microsoft.VisualStudio.LanguageServices.CSharp.Utilities;
 
internal sealed class BlankLineInGeneratedMethodFormattingRule : AbstractFormattingRule
{
    public static readonly BlankLineInGeneratedMethodFormattingRule Instance = new();
 
    private BlankLineInGeneratedMethodFormattingRule()
    {
    }
 
    public override AdjustNewLinesOperation GetAdjustNewLinesOperation(in SyntaxToken previousToken, in SyntaxToken currentToken, in NextGetAdjustNewLinesOperation nextOperation)
    {
        // case: insert blank line in empty method body.
        if (previousToken.Kind() == SyntaxKind.OpenBraceToken &&
            currentToken.Kind() == SyntaxKind.CloseBraceToken)
        {
            if (currentToken.Parent.Kind() == SyntaxKind.Block &&
                currentToken.Parent.Parent.Kind() == SyntaxKind.MethodDeclaration)
            {
                return FormattingOperations.CreateAdjustNewLinesOperation(2, AdjustNewLinesOption.ForceLines);
            }
        }
 
        return nextOperation.Invoke(in previousToken, in currentToken);
    }
}