exports.up = async (knex) => {
	await knex.raw(`
		CREATE OR REPLACE FUNCTION curate_search_query(query text) RETURNS tsquery AS $$
			SELECT to_tsquery('english', array_to_string(array(SELECT * FROM regexp_matches(query, '[A-Za-zÀ-ÖØ-öø-ÿ0-9]+', 'g')), '|'));
		$$ LANGUAGE SQL STABLE;

		CREATE OR REPLACE FUNCTION search_releases(query text) RETURNS SETOF releases_search_results AS $$
			SELECT results.release_id, ts_rank(results.document::tsvector, curate_search_query(query)) as rank
			FROM (
				SELECT releases_search.release_id, document
				FROM releases_search
				WHERE document::tsvector @@ curate_search_query(query)
			) AS results
			ORDER BY rank DESC;
		$$ LANGUAGE SQL STABLE;

		COMMENT ON FUNCTION search_releases IS E'@sortable';
	`);
};

exports.down = async (knex) => {
	await knex.raw(`
		CREATE OR REPLACE FUNCTION search_releases(query text) RETURNS SETOF releases_search_results AS $$
			SELECT releases.id, ranks.rank FROM (
				SELECT
					releases_search.release_id,
					ts_rank(releases_search.document, to_tsquery('english', array_to_string(array(SELECT * FROM regexp_matches(query, '[A-Za-zÀ-ÖØ-öø-ÿ0-9]+', 'g')), '|'))) AS rank
				FROM releases_search
				) ranks
			LEFT JOIN releases ON releases.id = ranks.release_id
			WHERE ranks.rank > 0
			ORDER BY ranks.rank DESC;
		$$ LANGUAGE SQL STABLE;

		DROP FUNCTION curate_search_query;
		COMMENT ON FUNCTION search_releases IS E'@sortable';
	`);
};