-- Evergreen DB patch 0576.fix_maintain_901_quoting.sql
--
-- Fix for bug LP#809540 - fixes crash when inserting or updating
-- bib whose tcn_value contains regex metacharacters.
--
BEGIN;

-- check whether patch can be applied
SELECT evergreen.upgrade_deps_block_check('0576', :eg_version);

CREATE OR REPLACE FUNCTION evergreen.maintain_901 () RETURNS TRIGGER AS $func$
DECLARE
    use_id_for_tcn BOOLEAN;
BEGIN
    -- Remove any existing 901 fields before we insert the authoritative one
    NEW.marc := REGEXP_REPLACE(NEW.marc, E'<datafield[^>]*?tag="901".+?</datafield>', '', 'g');

    IF TG_TABLE_SCHEMA = 'biblio' THEN
        -- Set TCN value to record ID?
        SELECT enabled FROM config.global_flag INTO use_id_for_tcn
            WHERE name = 'cat.bib.use_id_for_tcn';

        IF use_id_for_tcn = 't' THEN
            NEW.tcn_value := NEW.id;
        END IF;

        NEW.marc := REGEXP_REPLACE(
            NEW.marc,
            E'(</(?:[^:]*?:)?record>)',
            E'<datafield tag="901" ind1=" " ind2=" ">' ||
                '<subfield code="a">' || REPLACE(evergreen.xml_escape(NEW.tcn_value), E'\\', E'\\\\') || E'</subfield>' ||
                '<subfield code="b">' || REPLACE(evergreen.xml_escape(NEW.tcn_source), E'\\', E'\\\\') || E'</subfield>' ||
                '<subfield code="c">' || NEW.id || E'</subfield>' ||
                '<subfield code="t">' || TG_TABLE_SCHEMA || E'</subfield>' ||
                CASE WHEN NEW.owner IS NOT NULL THEN '<subfield code="o">' || NEW.owner || E'</subfield>' ELSE '' END ||
                CASE WHEN NEW.share_depth IS NOT NULL THEN '<subfield code="d">' || NEW.share_depth || E'</subfield>' ELSE '' END ||
             E'</datafield>\\1'
        );
    ELSIF TG_TABLE_SCHEMA = 'authority' THEN
        NEW.marc := REGEXP_REPLACE(
            NEW.marc,
            E'(</(?:[^:]*?:)?record>)',
            E'<datafield tag="901" ind1=" " ind2=" ">' ||
                '<subfield code="c">' || NEW.id || E'</subfield>' ||
                '<subfield code="t">' || TG_TABLE_SCHEMA || E'</subfield>' ||
             E'</datafield>\\1'
        );
    ELSIF TG_TABLE_SCHEMA = 'serial' THEN
        NEW.marc := REGEXP_REPLACE(
            NEW.marc,
            E'(</(?:[^:]*?:)?record>)',
            E'<datafield tag="901" ind1=" " ind2=" ">' ||
                '<subfield code="c">' || NEW.id || E'</subfield>' ||
                '<subfield code="t">' || TG_TABLE_SCHEMA || E'</subfield>' ||
                '<subfield code="o">' || NEW.owning_lib || E'</subfield>' ||
                CASE WHEN NEW.record IS NOT NULL THEN '<subfield code="r">' || NEW.record || E'</subfield>' ELSE '' END ||
             E'</datafield>\\1'
        );
    ELSE
        NEW.marc := REGEXP_REPLACE(
            NEW.marc,
            E'(</(?:[^:]*?:)?record>)',
            E'<datafield tag="901" ind1=" " ind2=" ">' ||
                '<subfield code="c">' || NEW.id || E'</subfield>' ||
                '<subfield code="t">' || TG_TABLE_SCHEMA || E'</subfield>' ||
             E'</datafield>\\1'
        );
    END IF;

    RETURN NEW;
END;
$func$ LANGUAGE PLPGSQL;

COMMIT;
