// 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.Collections.Generic;
using Microsoft.VisualStudio.Text;
using Microsoft.VisualStudio.Text.Editor;
using Roslyn.Utilities;
 
namespace Microsoft.CodeAnalysis.Editor.Shared.Extensions;
 
internal static class ITextSelectionExtensions
{
    public static NormalizedSnapshotSpanCollection GetSnapshotSpansOnBuffer(this ITextSelection selection, ITextBuffer subjectBuffer)
    {
        Contract.ThrowIfNull(selection);
        Contract.ThrowIfNull(subjectBuffer);
 
        var list = new List<SnapshotSpan>();
        foreach (var snapshotSpan in selection.SelectedSpans)
        {
            list.AddRange(selection.TextView.BufferGraph.MapDownToBuffer(snapshotSpan, SpanTrackingMode.EdgeExclusive, subjectBuffer));
        }
 
        return new NormalizedSnapshotSpanCollection(list);
    }
}