-- Phase 4 - Reminders expansion (POST-AUDIT-SPEC §2 + MASTER-PLAN §D).
--
-- Adds:
--   1. interests.reminder_note - cadence note surfaced in notification body + inbox row.
--   2. reminders.yacht_id - fourth supported entity link (was: client/interest/berth).
--   3. reminders.fired_at - worker idempotency; set once the firing notification is
--      created so a parallel worker can't double-fire.
--   4. user_profiles.preferences gains `digest_time_of_day` (JSONB key; no DDL).
--
-- The existing reminders table already carries title/note/dueAt/priority/assignedTo/
-- snoozedUntil/googleCalendarEventId - those columns are reused unchanged. No new
-- table; standalone tasks set client_id/interest_id/berth_id/yacht_id all NULL.

ALTER TABLE interests
  ADD COLUMN IF NOT EXISTS reminder_note text;

ALTER TABLE reminders
  ADD COLUMN IF NOT EXISTS yacht_id text,
  ADD COLUMN IF NOT EXISTS fired_at timestamptz;

-- Yacht FK with the same ON DELETE behaviour as the other entity links.
DO $$
BEGIN
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint
    WHERE conname = 'reminders_yacht_id_fkey'
  ) THEN
    ALTER TABLE reminders
      ADD CONSTRAINT reminders_yacht_id_fkey
      FOREIGN KEY (yacht_id) REFERENCES yachts(id) ON DELETE SET NULL;
  END IF;
END $$;

-- Index supports the worker scan: "give me every pending reminder whose
-- due_at has passed and we haven't fired yet."
CREATE INDEX IF NOT EXISTS idx_reminders_due_unfired
  ON reminders (port_id, due_at)
  WHERE fired_at IS NULL AND status IN ('pending', 'snoozed');

-- Comments for downstream readers.
COMMENT ON COLUMN interests.reminder_note IS
  'Phase 4: optional cadence note surfaced in reminder notification body + inbox row. NULL = use the default cadence copy.';
COMMENT ON COLUMN reminders.yacht_id IS
  'Phase 4: link to a yacht for yacht-scoped reminders. Mirrors client_id/interest_id/berth_id semantics.';
COMMENT ON COLUMN reminders.fired_at IS
  'Phase 4: set by the worker once the due-reminder notification has been created. NULL = not yet fired; used as the worker idempotency gate (alongside the partial index above).';