namespace EnVisage
{
    using System;
    using System.Data.Entity;
    using System.Data.SqlClient;

    public static class DbContextExtensions
    {
        public static string GetClientConnectionId(this DbContext context)
        {
            if (context == null)
                throw new ArgumentNullException(nameof(context));

            // if SaveChanges is called from external parent transaction
            if (context.Database != null && context.Database.CurrentTransaction != null)
                if (context.Database.CurrentTransaction.UnderlyingTransaction != null)
                    if (context.Database.CurrentTransaction.UnderlyingTransaction.Connection != null)
                        if (context.Database.CurrentTransaction.UnderlyingTransaction.Connection is SqlConnection)
                            return (context.Database.CurrentTransaction.UnderlyingTransaction.Connection as SqlConnection).ClientConnectionId.ToString();

            return null;
        }
    }
}