FT search with I18N in Postgresql

search.sql

-- search
-- Perform a full text search in I18N using HStore
-- @param text $1 the language to search
-- @param text $2 the search string
-- @return int4 id The identifier of the searched table
-- @return float4 rank The ranking function result.
-- @return text excerpt An extract of text containing the searched words surrounded with <strong>.</strong>.

CREATE OR REPLACE FUNCTION test.search(text, text) RETURNS TABLE (id int4, rank float4, excerpt text) LANGUAGE sql AS $_$
    SELECT 
      id, 
      ts_rank_cd(CAST(ft_name->$1 AS tsvector), query, 32) AS rank,
      ts_headline($1::regconfig, description->$1, query, 'StartSel=<strong> StopSel=</strong>') AS excerpt
    FROM 
      test.something, 
      to_tsquery($1::regconfig, $2) query 
    WHERE 
      ft_name->$1 @@ query
    ORDER BY rank DESC
$_$
;

structure.sql

CREATE SCHEMA test;
CREATE TABLE test.something (id serial PRIMARY KEY, name hstore, ft_name hstore, description hstore);

CREATE OR REPLACE FUNCTION i18n_to_tsvector(test.something) RETURNS hstore LANGUAGE sql AS $_$
WITH 
  trans_name (culture, tsvector) AS (
    SELECT                                                         
      (a).key,                                                                                            
      setweight(to_tsvector((a).key::regconfig, (a).value), 'A') || setweight(to_tsvector((b).key::regconfig, (b).value), 'B')
    FROM 
      (SELECT each(($1).name)) name (a)
        JOIN (SELECT each(($1).description)) description (b) ON (a).key = (b).key
  )
    SELECT 
      hstore(array_agg(culture), array_agg(tsvector::text)) 
    FROM
      trans_name
$_$ 
;


CREATE OR REPLACE FUNCTION before_each_insert_update() RETURNS TRIGGER LANGUAGE plpgsql AS $_$           
BEGIN                                     
    NEW.ft_name := i18n_to_tsvector(NEW);
    RETURN NEW;
END;                                 
$_$                                                                                             
;