ALTER TABLE services ADD COLUMN config_files text NOT NULL DEFAULT '';
ALTER TABLE services ADD COLUMN desired_ref  text NOT NULL DEFAULT '';

CREATE TABLE update_jobs (
    id               bigserial PRIMARY KEY,
    service_id       bigint NOT NULL REFERENCES services (id),
    agent_id         bigint REFERENCES agents (id),
    from_ref         text NOT NULL DEFAULT '',
    to_ref           text NOT NULL,
    trigger          text NOT NULL CHECK (trigger IN ('manual', 'webhook', 'poll')),
    requested_by     text NOT NULL DEFAULT '',
    status           text NOT NULL CHECK (status IN ('queued', 'running', 'succeeded', 'failed')),
    output           text NOT NULL DEFAULT '',
    output_truncated boolean NOT NULL DEFAULT false,
    error            text NOT NULL DEFAULT '',
    created_at       timestamptz NOT NULL,
    started_at       timestamptz,
    finished_at      timestamptz
);

-- One queued or running job per service. CreateJob relies on this index to
-- turn a second concurrent click into ErrJobActive.
CREATE UNIQUE INDEX update_jobs_one_active ON update_jobs (service_id)
    WHERE status IN ('queued', 'running');
CREATE INDEX update_jobs_by_service ON update_jobs (service_id, id DESC);
CREATE INDEX update_jobs_active_by_agent ON update_jobs (agent_id)
    WHERE status IN ('queued', 'running');