// 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.Text;

namespace Microsoft.CodeAnalysis;

/// <summary>
/// A class that represents both a source text and its version stamp.
/// </summary>
public sealed class TextAndVersion
{
    /// <summary>
    /// The source text.
    /// </summary>
    public SourceText Text { get; }

    /// <summary>
    /// The version of the source text
    /// </summary>
    public VersionStamp Version { get; }

    /// <summary>
    /// Obsolete.
    /// </summary>
    [Obsolete("Use Document.FilePath instead", false)]
    public string FilePath { get; }

    /// <summary>
    /// If an error occurred while loading the text the corresponding diagnostic, otherwise null.
    /// </summary>
    internal string? ExceptionMessage { get; }

    private TextAndVersion(SourceText text, VersionStamp version, string? filePath, string? exceptionMessage)
    {
        Text = text;
        Version = version;
        ExceptionMessage = exceptionMessage;

#pragma warning disable CS0618 // Type or member is obsolete
        FilePath = filePath ?? string.Empty;
#pragma warning restore
    }

    /// <summary>
    /// Create a new <see cref="TextAndVersion"/> instance.
    /// </summary>
    /// <param name="text">The text</param>
    /// <param name="version">The version</param>
    /// <param name="filePath">Obsolete.</param>
    public static TextAndVersion Create(SourceText text, VersionStamp version, string? filePath = null)
        => new(text ?? throw new ArgumentNullException(nameof(text)), version, filePath, exceptionMessage: null);

    /// <summary>
    /// Create a new <see cref="TextAndVersion"/> instance.
    /// </summary>
    /// <param name="text">The text</param>
    /// <param name="version">The version</param>
    internal static TextAndVersion Create(SourceText text, VersionStamp version, string? filePath, string? exceptionMessage)
        => new(text, version, filePath, exceptionMessage);
}