-- 0003_w0_hardening.sql
--
-- W0 hardening migration. Folds two ad-hoc maintenance scripts into the
-- canonical migration stream so a clean install on a fresh VPS produces a
-- secured, fully-searchable database without any post-bootstrap scripts.
--
--   F4   — RLS on public.relations (drift vs every other public.* table).
--   TD#2 — is_searchable column + reclassification + partial index, AND the
--          updated hybrid_search_chunks() that honors it. (Previously lived
--          in scripts/maintain/47_mark_unsearchable_chunks.sql + 48_*.sql.)
--
-- Idempotent. Safe to re-run.

BEGIN;

-- IMPORTANT: public.chunks / .entities / .relations are owned by
-- `supabase_admin` (not `postgres`). Postgres enforces ownership on RLS DDL
-- even for superusers. Run this migration as:
--
--   docker exec -i disclosure-db psql -U supabase_admin < 0003_w0_hardening.sql
--
-- The `supabase_admin` role has socket-trust auth on the local container.

-- ─────────────────────────────────────────────────────────────────────────
-- F4 · RLS on public.relations
-- ─────────────────────────────────────────────────────────────────────────
ALTER TABLE public.relations ENABLE ROW LEVEL SECURITY;

DROP POLICY IF EXISTS relations_read ON public.relations;
CREATE POLICY relations_read ON public.relations FOR SELECT USING (TRUE);

GRANT SELECT ON public.relations TO anon, authenticated;

-- ─────────────────────────────────────────────────────────────────────────
-- TD#2 · is_searchable column + reclassification + partial index
-- ─────────────────────────────────────────────────────────────────────────
ALTER TABLE public.chunks
  ADD COLUMN IF NOT EXISTS is_searchable BOOLEAN NOT NULL DEFAULT TRUE;

UPDATE public.chunks SET is_searchable = TRUE;

UPDATE public.chunks SET is_searchable = FALSE
WHERE type IN (
  'page_number',
  'blank',
  'stamp',
  'classification_banner',
  'classification_marking'
);

UPDATE public.chunks SET is_searchable = FALSE
WHERE type IN (
  'salutation',
  'complimentary_close',
  'section_heading',
  'section_header',
  'heading',
  'title',
  'subtitle',
  'date_line',
  'bulleted_item',
  'field_value',
  'field_entry',
  'table_marker',
  'form_field',
  'form_header',
  'routing_block',
  'distribution_list',
  'file_number',
  'marginalia'
)
AND LENGTH(COALESCE(content_en, content_pt, '')) < 50;

CREATE INDEX IF NOT EXISTS chunks_searchable_idx
  ON public.chunks (chunk_pk) WHERE is_searchable;

-- ─────────────────────────────────────────────────────────────────────────
-- TD#2 · hybrid_search_chunks honors is_searchable
-- Body identical to 0002's canonical, plus `AND c.is_searchable` in both
-- the bm25 and dense CTEs. Replaces the function in place.
-- ─────────────────────────────────────────────────────────────────────────
DROP FUNCTION IF EXISTS public.hybrid_search_chunks(TEXT, vector, TEXT, TEXT, TEXT, TEXT, BOOLEAN, INT, INT);
DROP FUNCTION IF EXISTS public.hybrid_search_chunks(TEXT, vector, TEXT, TEXT, TEXT, TEXT, BOOLEAN, INT, INT, DOUBLE PRECISION);
CREATE OR REPLACE FUNCTION public.hybrid_search_chunks(
  q_text       TEXT,
  q_embedding  vector(1024),
  q_lang       TEXT DEFAULT 'pt',
  q_doc_id     TEXT DEFAULT NULL,
  q_type       TEXT DEFAULT NULL,
  q_classification TEXT DEFAULT NULL,
  q_ufo_only   BOOLEAN DEFAULT FALSE,
  k            INT DEFAULT 100,
  rrf_k        INT DEFAULT 60,
  max_dense_dist DOUBLE PRECISION DEFAULT 0.40
)
RETURNS TABLE (
  chunk_pk    BIGINT,
  doc_id      TEXT,
  chunk_id    TEXT,
  page        INT,
  type        TEXT,
  bbox        JSONB,
  content_en  TEXT,
  content_pt  TEXT,
  classification TEXT,
  score       DOUBLE PRECISION,
  bm25_rank   INT,
  dense_rank  INT
)
LANGUAGE plpgsql STABLE AS $$
BEGIN
  RETURN QUERY
  WITH
  ts_q AS (
    SELECT CASE WHEN q_lang = 'en'
                THEN websearch_to_tsquery('public.en_unaccent'::regconfig, q_text)
                ELSE websearch_to_tsquery('public.pt_unaccent'::regconfig, q_text)
            END AS q
  ),
  bm25 AS (
    SELECT c.chunk_pk,
           row_number() OVER (ORDER BY
             ts_rank_cd(
               CASE WHEN q_lang = 'en' THEN c.ts_en ELSE c.ts_pt END,
               (SELECT q FROM ts_q)
             ) DESC NULLS LAST
           )::INT AS r
    FROM public.chunks c
    WHERE c.is_searchable
      AND (CASE WHEN q_lang = 'en' THEN c.ts_en ELSE c.ts_pt END) @@ (SELECT q FROM ts_q)
      AND (q_doc_id IS NULL OR c.doc_id = q_doc_id)
      AND (q_type IS NULL OR c.type = q_type)
      AND (q_classification IS NULL OR c.classification = q_classification)
      AND (NOT q_ufo_only OR c.ufo_anomaly = TRUE)
    LIMIT k
  ),
  dense AS (
    SELECT c.chunk_pk,
           row_number() OVER (ORDER BY c.embedding <=> q_embedding)::INT AS r
    FROM public.chunks c
    WHERE c.is_searchable
      AND c.embedding IS NOT NULL
      AND (c.embedding <=> q_embedding) < max_dense_dist
      AND (q_doc_id IS NULL OR c.doc_id = q_doc_id)
      AND (q_type IS NULL OR c.type = q_type)
      AND (q_classification IS NULL OR c.classification = q_classification)
      AND (NOT q_ufo_only OR c.ufo_anomaly = TRUE)
    ORDER BY c.embedding <=> q_embedding
    LIMIT k
  ),
  fused AS (
    SELECT COALESCE(b.chunk_pk, d.chunk_pk) AS chunk_pk,
           ((1.0::DOUBLE PRECISION / (rrf_k + COALESCE(b.r, k + 1))::DOUBLE PRECISION) +
            (1.0::DOUBLE PRECISION / (rrf_k + COALESCE(d.r, k + 1))::DOUBLE PRECISION)) AS score,
           b.r AS bm25_rank,
           d.r AS dense_rank
    FROM bm25 b
    FULL OUTER JOIN dense d USING (chunk_pk)
  )
  SELECT c.chunk_pk, c.doc_id, c.chunk_id, c.page, c.type, c.bbox,
         c.content_en, c.content_pt, c.classification,
         f.score, f.bm25_rank, f.dense_rank
  FROM fused f
  JOIN public.chunks c USING (chunk_pk)
  ORDER BY f.score DESC
  LIMIT k;
END
$$;

GRANT EXECUTE ON FUNCTION public.hybrid_search_chunks TO anon, authenticated;

COMMIT;