// 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 System.Diagnostics;
using System.Linq;
using System.Text;
using Microsoft.CodeAnalysis;
 
namespace Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel;
 
internal partial class AbstractCodeModelService : ICodeModelService
{
    protected abstract AbstractNodeNameGenerator CreateNodeNameGenerator();
 
    protected abstract class AbstractNodeNameGenerator
    {
        protected abstract bool IsNameableNode(SyntaxNode node);
        protected abstract void AppendNodeName(StringBuilder builder, SyntaxNode node);
 
        protected static void AppendDotIfNeeded(StringBuilder builder)
        {
            if (builder.Length > 0 &&
                char.IsLetterOrDigit(builder[^1]))
            {
                builder.Append('.');
            }
        }
 
        protected static void AppendArity(StringBuilder builder, int arity)
        {
            if (arity > 0)
            {
                builder.Append("`" + arity);
            }
        }
 
        public string GenerateName(SyntaxNode node)
        {
            Debug.Assert(IsNameableNode(node));
 
            var builder = new StringBuilder();
 
            var ancestors = node.Ancestors().ToArray();
            for (var i = ancestors.Length - 1; i >= 0; i--)
            {
                var ancestor = ancestors[i];
 
                // We skip "unnameable" nodes to ensure that we don't add empty names
                // for nodes like the compilation unit or field declarations.
                if (IsNameableNode(ancestor))
                {
                    AppendNodeName(builder, ancestor);
                }
            }
 
            AppendNodeName(builder, node);
 
            return builder.ToString();
        }
    }
}