ALTER TABLE rag_document_pages
  ADD COLUMN IF NOT EXISTS quality_outcome text NULL,
  ADD COLUMN IF NOT EXISTS quality_warnings jsonb NOT NULL DEFAULT '[]'::jsonb,
  ADD COLUMN IF NOT EXISTS blocking_reasons jsonb NOT NULL DEFAULT '[]'::jsonb,
  ADD COLUMN IF NOT EXISTS primary_blocking_reason text NULL,
  ADD COLUMN IF NOT EXISTS quality_report_sha256 char(64) NULL;

DO $$
BEGIN
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint
    WHERE conrelid = 'rag_document_pages'::regclass
      AND conname = 'rag_document_pages_quality_outcome_check'
  ) THEN
    ALTER TABLE rag_document_pages
      ADD CONSTRAINT rag_document_pages_quality_outcome_check
      CHECK (quality_outcome IN ('accepted', 'warning', 'blocked'));
  END IF;
END $$;