-- Visitor journey reconstruction. Two tables, two retention policies.
--
-- session_events: every analytics event the SvelteKit /api/track endpoint
-- receives, keyed by the anon_id cookie set in hooks.server.ts. This buffer
-- is the source for journey reconstruction when a visitor submits the
-- booking form. It is pruned aggressively (24h TTL) so we don't hoard
-- behavioural data for visitors who never enquire.
--
-- submission_journeys: when a visitor submits the booking/contact form,
-- /api/track/promote copies their recent session_events into this table
-- linked to the submission email. These rows are kept so the owner can
-- review the journey from the CP dashboard.
--
-- The promotion step is the only place where an anonymous browsing record
-- becomes linked to a named person, and it only happens because that
-- person chose to submit a form. The privacy policy covers this.

create table if not exists session_events (
  id bigserial primary key,
  anon_id text not null,
  event_name text not null,
  page_path text,
  params jsonb not null default '{}'::jsonb,
  created_at timestamptz not null default now()
);

create index if not exists session_events_anon_idx
  on session_events (anon_id, created_at);

-- Used by the probabilistic prune in /api/track to find rows past TTL.
create index if not exists session_events_created_idx
  on session_events (created_at);

create table if not exists submission_journeys (
  id bigserial primary key,
  email text not null,
  anon_id text,
  -- Snapshot of session_events rows at promotion time (server-captured).
  events jsonb not null default '[]'::jsonb,
  -- Client-side sessionStorage buffer sent with the promote request, as a
  -- fallback for events that never reached /api/track (e.g. blocked at the
  -- network layer alongside gtag).
  client_events jsonb not null default '[]'::jsonb,
  created_at timestamptz not null default now()
);

create index if not exists submission_journeys_email_idx
  on submission_journeys (email, created_at desc);