public HttpResponseMessage AddPresence([FromBody] Presence newPresence)
        {
            if (ModelState.IsValid)
            {
                int presenceId;
                try
                {
                    if (LogicUser.AddPresence(newPresence))
                    {
                        presenceId = LogicUser.GetCurrentPresenceId(newPresence);
                        return(new HttpResponseMessage(HttpStatusCode.Created)
                        {
                            Content = new ObjectContent <Int32>(presenceId, new JsonMediaTypeFormatter())
                        });
                    }
                }
                catch (Exception e)
                {
                    new HttpResponseMessage(HttpStatusCode.BadRequest)
                    {
                        Content = new ObjectContent <String>($"Can not add to DB - {e.Message}", new JsonMediaTypeFormatter())
                    };
                }
            }
            ;

            List <string> ErrorList = new List <string>();

            //if the code reached this part - the user is not valid
            foreach (var item in ModelState.Values)
            {
                foreach (var err in item.Errors)
                {
                    ErrorList.Add(err.ErrorMessage);
                }
            }

            return(new HttpResponseMessage(HttpStatusCode.BadRequest)
            {
                Content = new ObjectContent <List <string> >(ErrorList, new JsonMediaTypeFormatter())
            });
        }