-- EVAL OFFSET: fixed UTC epoch phase (offset + k * interval), deterministic.

CREATE TABLE eval_offset_input (
  ts TIMESTAMP(3) TIME INDEX,
  series STRING,
  v DOUBLE,
  PRIMARY KEY(series)
);

-- Scheduled at odd seconds (1 + 2k): phase anchored to the Unix epoch.
CREATE FLOW eval_offset_phase_flow
SINK TO eval_offset_phase_sink
EVAL INTERVAL '2s'
EVAL OFFSET '1s'
AS
SELECT date_trunc('second', now()) AS ts, count(v) AS c
FROM eval_offset_input
GROUP BY date_trunc('second', now());

SHOW CREATE FLOW eval_offset_phase_flow;

SELECT flow_definition FROM information_schema.flows WHERE flow_name = 'eval_offset_phase_flow';

INSERT INTO eval_offset_input VALUES
  (now(), 'a', 1.0),
  (now(), 'b', 2.0);

-- SQLNESS SLEEP 5s

-- Prove the offset phase: every row the offset flow wrote has an odd
-- second-of-minute (1 + 2k is always odd). This is deterministic regardless
-- of the exact wall-clock alignment of the evaluations.
SELECT
  count(*) > 0 AS offset_flow_ran,
  bool_and(date_part('second', ts)::BIGINT % 2 = 1) AS offset_flow_at_odd_seconds
FROM eval_offset_phase_sink;

CREATE FLOW invalid_eval_offset_no_interval
SINK TO invalid_eval_offset_sink
EVAL OFFSET '1s'
AS SELECT 1;

CREATE FLOW invalid_eval_offset_too_large
SINK TO invalid_eval_offset_sink
EVAL INTERVAL '1s'
EVAL OFFSET '2s'
AS SELECT 1;

CREATE FLOW invalid_eval_offset_fractional
SINK TO invalid_eval_offset_sink
EVAL INTERVAL '1s'
EVAL OFFSET '0.5s'
AS SELECT 1;

CREATE FLOW invalid_eval_offset_fractional_interval
SINK TO invalid_eval_offset_sink
EVAL INTERVAL '1.5s'
EVAL OFFSET '1s'
AS SELECT 1;

DROP FLOW eval_offset_phase_flow;
DROP TABLE eval_offset_phase_sink;
DROP TABLE eval_offset_input;