// 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.Collections.Generic;
using System.Linq;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Classification;
 
namespace Microsoft.CodeAnalysis.Interactive;
 
internal sealed partial class InertClassifierProvider
{
    private sealed class InertClassifier : IClassifier
    {
        private readonly ITextBuffer _textBuffer;
 
        public InertClassifier(ITextBuffer textBuffer)
            => _textBuffer = textBuffer;
 
#pragma warning disable 67
        public event EventHandler<ClassificationChangedEventArgs> ClassificationChanged;
#pragma warning restore 67
 
        public IList<ClassificationSpan> GetClassificationSpans(SnapshotSpan span)
        {
            // See if we have cached classifications for this text buffer and return the ones
            // that intersect the requested span if we do.
            if (_textBuffer.Properties.TryGetProperty<IList<ClassificationSpan>>(s_classificationsKey, out var classifications))
            {
                return [.. classifications.Where(c => c.Span.IntersectsWith(span))];
            }
 
            return [];
        }
    }
}