// 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.LanguageService;

namespace Microsoft.CodeAnalysis.GenerateEqualsAndGetHashCodeFromMembers;

internal abstract partial class AbstractGenerateEqualsAndGetHashCodeService
{
    /// <summary>
    /// Specialized formatter for the "return a == obj.a &amp;&amp; b == obj.b &amp;&amp; c == obj.c &amp;&amp; ...
    /// code that we spit out.
    /// </summary>
    private sealed class FormatLargeBinaryExpressionRule(ISyntaxFactsService syntaxFacts) : AbstractFormattingRule
    {
        private readonly ISyntaxFactsService _syntaxFacts = syntaxFacts;

        /// <summary>
        /// Wrap the large &amp;&amp; expression after every &amp;&amp; token.
        /// </summary>
        public override AdjustNewLinesOperation? GetAdjustNewLinesOperation(
            in SyntaxToken previousToken, in SyntaxToken currentToken, in NextGetAdjustNewLinesOperation nextOperation)
        {
            if (_syntaxFacts.IsLogicalAndExpression(previousToken.Parent))
            {
                return FormattingOperations.CreateAdjustNewLinesOperation(1, AdjustNewLinesOption.PreserveLines);
            }

            return nextOperation.Invoke(in previousToken, in currentToken);
        }

        /// <summary>
        /// Align all the wrapped parts of the expression with the token after 'return'.
        /// That way we get:
        /// 
        /// return a == obj.a &amp;&amp;
        ///        b == obj.b &amp;&amp;
        ///        ...
        /// </summary>
        public override void AddIndentBlockOperations(
            List<IndentBlockOperation> list, SyntaxNode node, in NextIndentBlockOperationAction nextOperation)
        {
            if (_syntaxFacts.IsReturnStatement(node))
            {
                var expr = _syntaxFacts.GetExpressionOfReturnStatement(node);
                if (expr?.ChildNodesAndTokens().Count > 1)
                {
                    list.Add(FormattingOperations.CreateRelativeIndentBlockOperation(
                        expr.GetFirstToken(),
                        expr.GetFirstToken().GetNextToken(),
                        node.GetLastToken(),
                        indentationDelta: 0,
                        option: IndentBlockOption.RelativePosition));

                    return;
                }
            }

            nextOperation.Invoke();
        }
    }
}