// 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.Generic;
using Microsoft.CodeAnalysis.Formatting.Rules;
using Microsoft.CodeAnalysis.PooledObjects;
 
namespace Microsoft.CodeAnalysis.CSharp.Formatting;
 
// the default provider that will be called by the engine at the end of provider's chain.
// there is no way for a user to be remove this provider.
//
// to reduce number of unnecessary heap allocations, most of them just return null.
internal sealed class DefaultOperationProvider : AbstractFormattingRule
{
    public static readonly DefaultOperationProvider Instance = new();
 
    private DefaultOperationProvider()
    {
    }
 
    public override void AddSuppressOperations(ArrayBuilder<SuppressOperation> list, SyntaxNode node, in NextSuppressOperationAction nextOperation)
    {
    }
 
    public override void AddAnchorIndentationOperations(List<AnchorIndentationOperation> list, SyntaxNode node, in NextAnchorIndentationOperationAction nextOperation)
    {
    }
 
    public override void AddIndentBlockOperations(List<IndentBlockOperation> list, SyntaxNode node, in NextIndentBlockOperationAction nextOperation)
    {
    }
 
    public override void AddAlignTokensOperations(List<AlignTokensOperation> list, SyntaxNode node, in NextAlignTokensOperationAction nextOperation)
    {
    }
 
    public override AdjustNewLinesOperation? GetAdjustNewLinesOperation(in SyntaxToken previousToken, in SyntaxToken currentToken, in NextGetAdjustNewLinesOperation nextOperation)
        => null;
 
    // return 1 space for every token pairs as a default operation
    public override AdjustSpacesOperation GetAdjustSpacesOperation(in SyntaxToken previousToken, in SyntaxToken currentToken, in NextGetAdjustSpacesOperation nextOperation)
    {
        var space = currentToken.Kind() == SyntaxKind.EndOfFileToken ? 0 : 1;
        return FormattingOperations.CreateAdjustSpacesOperation(space, AdjustSpacesOption.DefaultSpacesIfOnSingleLine);
    }
}