// 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.Diagnostics.CodeAnalysis;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.Text;

namespace Microsoft.CodeAnalysis;

internal interface ITextAndVersionSource
{
    /// <summary>
    /// True if <see cref="SourceText"/> can be reloaded.
    /// </summary>
    bool CanReloadText { get; }

    /// <summary>
    /// Retrieves the underlying <see cref="TextLoader"/> if that's what this <see cref="ITextAndVersionSource"/> was
    /// created from and still has access to.
    /// </summary>
    TextLoader? TextLoader { get; }

    bool TryGetValue(LoadTextOptions options, [MaybeNullWhen(false)] out TextAndVersion value);
    TextAndVersion GetValue(LoadTextOptions options, CancellationToken cancellationToken);
    Task<TextAndVersion> GetValueAsync(LoadTextOptions options, CancellationToken cancellationToken);

    bool TryGetVersion(LoadTextOptions options, out VersionStamp version);

    /// <summary>
    /// Retrieves just the version information from this instance.  Cheaper than <see cref="GetValueAsync"/> when only
    /// the version is needed, and avoiding loading the text is desirable.
    /// </summary>
    ValueTask<VersionStamp> GetVersionAsync(LoadTextOptions options, CancellationToken cancellationToken);
}