-- Dead man's switches become rows of their own.
--
-- 004 kept a team's switches in one string with one timeout and one severity,
-- which was enough to configure them and not enough to show them: there was no
-- thing to list, nothing to hang a status on, and every switch in a team had to
-- share a deadline. A row per switch gives each its own name, matcher, timeout
-- and severity, and gives the Team → Switches page something to be a list of.
--
-- The matcher keeps the syntax the string used, one matcher per row:
-- `alertname=Watchdog,cluster=prod`. The unit of monitoring is still the
-- fingerprint, so a matcher that many clusters satisfy is still one switch row
-- watching several independent heartbeats.
CREATE TABLE deadman_switches (
    id      BIGSERIAL PRIMARY KEY,
    team_id BIGINT NOT NULL REFERENCES teams(id) ON DELETE CASCADE,

    -- What the owner calls it. Defaults to the matcher when they do not say.
    name TEXT NOT NULL,

    -- "," separates the label conditions, "=" is exact equality, and alertname is
    -- mandatory: it is what keeps the sweeper's candidate query on an index.
    matcher TEXT NOT NULL,

    -- Seconds of silence before the switch is declared dead. Never zero: a switch
    -- that cannot fire is deleted, not disabled.
    timeout_seconds BIGINT NOT NULL CHECK (timeout_seconds > 0),

    -- The severity its incidents open at. See 004 for why they carry their own.
    severity TEXT NOT NULL DEFAULT 'critical',

    created_at BIGINT NOT NULL DEFAULT FLOOR(EXTRACT(EPOCH FROM now()))::bigint
);

CREATE INDEX deadman_switches_team_idx ON deadman_switches (team_id);

-- Carry every team's configuration over, one row per matcher. A team whose
-- timeout was zero had switches turned off, which is now "no rows".
INSERT INTO deadman_switches (team_id, name, matcher, timeout_seconds, severity)
SELECT c.team_id, btrim(m), btrim(m), c.timeout_seconds, c.severity
FROM   deadman_configs c,
       LATERAL regexp_split_to_table(c.matchers, ';') AS m
WHERE  c.timeout_seconds > 0
  AND  btrim(m) <> ''
ORDER  BY c.team_id;

-- The server seeds environment defaults into teams once, and remembers that it
-- did. An install that had a row per team was already seeded; without this
-- marker the first start after upgrading would seed teams that had switched
-- theirs off.
INSERT INTO settings (key, value)
SELECT 'deadman_seeded', '1'
WHERE  EXISTS (SELECT 1 FROM deadman_configs);

DROP TABLE deadman_configs;