// 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;
using Microsoft.CodeAnalysis.Collections;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Tagging;
 
namespace Microsoft.CodeAnalysis.Editor.Tagging;
 
internal partial class AbstractAsynchronousTaggerProvider<TTag>
{
    /// <summary>
    /// <see cref="Tagger"/> is a thin wrapper we create around the single shared <see cref="TagSource"/>.
    /// Clients can request and dispose these at will.  Once the last wrapper is disposed, the underlying
    /// <see cref="TagSource"/> will finally be disposed as well.
    /// </summary>
    private sealed partial class Tagger : EfficientTagger<TTag>, IDisposable
    {
        private readonly TagSource _tagSource;
 
        public Tagger(TagSource tagSource)
        {
            _tagSource = tagSource;
            _tagSource.OnTaggerAdded(this);
        }
 
        public override event EventHandler<SnapshotSpanEventArgs>? TagsChanged
        {
            add => _tagSource.TagsChanged += value;
            remove => _tagSource.TagsChanged -= value;
        }
 
        public override void Dispose()
            => _tagSource.OnTaggerDisposed(this);
 
        public override void AddTags(NormalizedSnapshotSpanCollection spans, SegmentedList<TagSpan<TTag>> tags)
            => _tagSource.AddTags(spans, tags);
    }
}