// 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.Linq;
using System.Runtime.InteropServices;
using Microsoft.CodeAnalysis;
using Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.InternalElements;
using Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.Interop;
using Microsoft.VisualStudio.LanguageServices.Implementation.Interop;
 
namespace Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.Collections;
 
[ComVisible(true)]
[ComDefaultInterface(typeof(ICodeElements))]
public sealed class AttributeArgumentCollection : AbstractCodeElementCollection
{
    internal static EnvDTE.CodeElements Create(
        CodeModelState state,
        CodeAttribute parent)
    {
        var collection = new AttributeArgumentCollection(state, parent);
        return (EnvDTE.CodeElements)ComAggregate.CreateAggregatedObject(collection);
    }
 
    private AttributeArgumentCollection(
        CodeModelState state,
        CodeAttribute parent)
        : base(state, parent)
    {
    }
 
    private CodeAttribute ParentAttribute
    {
        get { return (CodeAttribute)Parent; }
    }
 
    private SyntaxNode LookupNode()
        => this.ParentAttribute.LookupNode();
 
    protected override bool TryGetItemByIndex(int index, out EnvDTE.CodeElement element)
    {
        var node = LookupNode();
 
        var attributeArgumentNodes = CodeModelService.GetAttributeArgumentNodes(node);
        if (index >= 0 && index < attributeArgumentNodes.Count())
        {
            element = (EnvDTE.CodeElement)CodeAttributeArgument.Create(this.State, this.ParentAttribute, index);
            return true;
        }
 
        element = null;
        return false;
    }
 
    protected override bool TryGetItemByName(string name, out EnvDTE.CodeElement element)
    {
        var node = LookupNode();
        var currentIndex = 0;
 
        foreach (var child in CodeModelService.GetAttributeArgumentNodes(node))
        {
            var childName = CodeModelService.GetName(child);
            if (childName == name)
            {
                element = (EnvDTE.CodeElement)CodeAttributeArgument.Create(this.State, this.ParentAttribute, currentIndex);
                return true;
            }
 
            currentIndex++;
        }
 
        element = null;
        return false;
    }
 
    public override int Count
    {
        get
        {
            var node = LookupNode();
            return CodeModelService.GetAttributeArgumentNodes(node).Count();
        }
    }
}