// 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;
using System.Diagnostics;
using System.Runtime.InteropServices;
using Microsoft.CodeAnalysis;
using Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.Collections;
using Microsoft.VisualStudio.LanguageServices.Implementation.Interop;
using Microsoft.VisualStudio.LanguageServices.Implementation.Utilities;
 
namespace Microsoft.VisualStudio.LanguageServices.Implementation.CodeModel.InternalElements;
 
[ComVisible(true)]
[ComDefaultInterface(typeof(EnvDTE80.CodeAttributeArgument))]
public sealed class CodeAttributeArgument : AbstractCodeElement, EnvDTE80.CodeAttributeArgument
{
    internal static EnvDTE80.CodeAttributeArgument Create(CodeModelState state, CodeAttribute parent, int index)
    {
        Debug.Assert(parent != null);
        Debug.Assert(index >= 0);
 
        var newElement = new CodeAttributeArgument(state, parent, index);
        return (EnvDTE80.CodeAttributeArgument)ComAggregate.CreateAggregatedObject(newElement);
    }
 
    private readonly ParentHandle<CodeAttribute> _parentHandle;
    private readonly int _index;
 
    private CodeAttributeArgument(CodeModelState state, CodeAttribute parent, int index)
        : base(state, parent.FileCodeModel)
    {
        _parentHandle = new ParentHandle<CodeAttribute>(parent);
        _index = index;
    }
 
    protected override EnvDTE.CodeElements GetCollection()
        => GetCollection<CodeAttributeArgument>(this.Parent);
 
    internal override SyntaxNode LookupNode()
    {
        if (!TryLookupNode(out var node))
        {
            throw Exceptions.ThrowEUnexpected();
        }
 
        return node;
    }
 
    internal override bool TryLookupNode(out SyntaxNode node)
    {
        node = null;
 
        var attributeNode = _parentHandle.Value.LookupNode();
        if (attributeNode == null)
        {
            return false;
        }
 
        if (!CodeModelService.TryGetAttributeArgumentNode(attributeNode, _index, out var attributeArgumentNode))
        {
            return false;
        }
 
        node = attributeArgumentNode;
        return node != null;
    }
 
    public override EnvDTE.vsCMElement Kind
    {
        get
        {
            // TODO: VB returns (EnvDTE.vsCMElement)EnvDTE80.vsCMElement2.vsCMElementAttributeArgument
            return EnvDTE.vsCMElement.vsCMElementOther;
        }
    }
 
    public override object Parent
    {
        get { return _parentHandle.Value; }
    }
 
    public override EnvDTE.CodeElements Children
    {
        get { return EmptyCollection.Create(this.State, this); }
    }
 
    protected override string GetFullName()
    {
        // TODO: VB throws E_NOTIMPL
        throw Exceptions.ThrowEFail();
    }
 
    public string Value
    {
        get
        {
            return CodeModelService.GetAttributeArgumentValue(LookupNode());
        }
 
        set
        {
            throw new NotImplementedException();
        }
    }
 
    public new void Delete()
        => base.Delete();
}