using System.Text.RegularExpressions;

namespace Omika.HfSqlProbe;

internal static partial class SqlIdentifierValidator
{
    /// <summary>Accepts only letters, digits, and underscores.</summary>
    [GeneratedRegex(@"\A[A-Za-z_][A-Za-z0-9_]*\z")]
    private static partial Regex IdentifierPattern();

    public static bool IsValid(string name) => IdentifierPattern().IsMatch(name);

    /// <summary>Validates and returns the identifier, or throws on invalid input.</summary>
    public static string Validate(string name)
    {
        if (!IsValid(name))
            throw new ArgumentException(
                $"Invalid SQL identifier: '{name}'. Only [A-Za-z0-9_] allowed.");
        return name;
    }
}