public async Task <IActionResult> GetEntries(string parameter, string queryType, int?since, int?until)
        {
            var qt = int.TryParse(queryType, out var num)
                ? EnumConversions.FromInt <QueryType>(num)
                : EnumConversions.FromString <QueryType>(queryType);

            if (!qt)
            {
                return(BadRequest($"Invalid query type '{queryType}'."));
            }

            TermModel?termSince = null;

            if (since != null)
            {
                var tmp = await _terms.FromIdAsync(since.Value);

                if (!tmp)
                {
                    return(BadRequest($"Invalid since term '{since}'."));
                }

                termSince = tmp.Value;
            }


            TermModel?termUntil = null;

            if (until != null)
            {
                var tmp = await _terms.FromIdAsync(until.Value);

                if (!tmp)
                {
                    return(BadRequest($"Invalid since term '{since}'."));
                }

                termUntil = tmp.Value;
            }

            return(Ok(await _repo.QueryEntriesAsync(parameter, qt.Value, termSince, termUntil)));
        }