namespace ScadaLink.Commons.Interfaces.Services;

/// <summary>
/// Surfaces the local node's semantic role-within-cluster name so downstream
/// audit writers can stamp it on the SourceNode column.
/// </summary>
/// <remarks>
/// Conventional values follow the pattern <c>node-a</c>/<c>node-b</c> on site
/// nodes and <c>central-a</c>/<c>central-b</c> on central nodes. The value is
/// a free-form operator-supplied label — there is no enforced format. When the
/// configuration value is missing, empty, or whitespace, implementations
/// return <c>null</c> so audit writers can persist NULL rather than an empty
/// string.
/// </remarks>
public interface INodeIdentityProvider
{
    /// <summary>
    /// The configured semantic node name, trimmed of surrounding whitespace.
    /// <c>null</c> when unconfigured.
    /// </summary>
    string? NodeName { get; }
}