// 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.Immutable;
using System.Diagnostics.CodeAnalysis;
using System.Windows;
using Microsoft.VisualStudio.Shell.TableControl;
using Microsoft.VisualStudio.Shell.TableManager;
 
namespace Microsoft.VisualStudio.LanguageServices.FindUsages;
 
internal partial class StreamingFindUsagesPresenter
{
    // Name of the key used to retireve the whole entry object.
    internal const string SelfKeyName = "self";
 
    private class TableEntriesSnapshot(ImmutableArray<Entry> entries, int versionNumber) : WpfTableEntriesSnapshotBase
    {
        private readonly int _versionNumber = versionNumber;
        private readonly ImmutableArray<Entry> _entries = entries;
 
        public override int VersionNumber => _versionNumber;
 
        public override int Count => _entries.Length;
 
        public override int IndexOf(int currentIndex, ITableEntriesSnapshot newSnapshot)
        {
            // We only add items to the end of our list, and we never reorder.
            // As such, any index in us will map to the same index in any newer snapshot.
            return currentIndex;
        }
 
        public override bool TryGetValue(int index, string keyName, out object? content)
        {
            // TableControlEventProcessor.PreprocessNavigate needs to get an entry 
            // to call TryNavigateTo on it.
            if (keyName == SelfKeyName)
            {
                content = _entries[index];
                return true;
            }
 
            return _entries[index].TryGetValue(keyName, out content);
        }
 
        public override bool TryCreateColumnContent(
            int index, string columnName, bool singleColumnView, [NotNullWhen(true)] out FrameworkElement? content)
        {
            return _entries[index].TryCreateColumnContent(columnName, out content);
        }
    }
}