// 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 Microsoft.CodeAnalysis.Editing;
using Microsoft.CodeAnalysis.Shared.Extensions;

namespace Microsoft.CodeAnalysis.CSharp.Features.EmbeddedLanguages;

internal static class EmbeddedLanguageUtilities
{
    internal static void AddComment(SyntaxEditor editor, SyntaxToken stringLiteral, string commentContents)
    {
        var triviaList = SyntaxFactory.TriviaList(
            SyntaxFactory.Comment($"/*{commentContents}*/"),
            SyntaxFactory.ElasticSpace);
        var newStringLiteral = stringLiteral.WithLeadingTrivia(
            stringLiteral.LeadingTrivia.AddRange(triviaList));
        var parent = stringLiteral.GetRequiredParent();
        editor.ReplaceNode(
           parent,
           parent.ReplaceToken(stringLiteral, newStringLiteral));
    }

    public static string EscapeText(string text, SyntaxToken token)
    {
        // This function is called when Completion needs to escape something its going to insert into the user's
        // string token.  This means that we only have to escape things that completion could insert.  In this case,
        // the only regex character that is relevant is the \ character, and it's only relevant if we insert into a
        // normal string and not a verbatim string.  There are no other regex characters that completion will
        // produce that need any escaping.
        return token.Kind() is SyntaxKind.StringLiteralToken or SyntaxKind.Utf8StringLiteralToken && !token.IsVerbatimStringLiteral()
            ? text.Replace(@"\", @"\\")
            : text;
    }
}