-- 0005_warehouse: the notification placeholder. Phase 4 writes the storage quota alert here; phase 9 builds the
-- delivery (mail, the bell) on this table. Runs as ps_migrate; 0001's default privileges give ps_app SELECT,
-- INSERT, UPDATE, DELETE on it.

-- One row per alert. An alert is open until resolved_at is set. Acknowledging it does not resolve it: the
-- condition that raised it has to clear.
CREATE TABLE notification_events (
    id               bigserial PRIMARY KEY,
    kind             text NOT NULL,
    severity         text NOT NULL DEFAULT 'warning' CHECK (severity IN ('info', 'warning', 'critical')),
    subject          text,
    detail           jsonb NOT NULL DEFAULT '{}',
    created_at       timestamptz NOT NULL DEFAULT now(),
    resolved_at      timestamptz,
    acknowledged_at  timestamptz,
    acknowledged_by  uuid REFERENCES users (id)
);

-- At most one open alert per kind and subject.
CREATE UNIQUE INDEX notification_events_open ON notification_events (kind, coalesce(subject, ''))
    WHERE resolved_at IS NULL;
CREATE INDEX notification_events_created ON notification_events (created_at DESC);

GRANT USAGE, SELECT ON ALL SEQUENCES IN SCHEMA public TO ps_app;