DROP TRIGGER IF EXISTS trigger_flag ON osm_aerodrome_label_point;
DROP TRIGGER IF EXISTS trigger_refresh ON aerodrome_label.updates;

-- etldoc: osm_aerodrome_label_point -> osm_aerodrome_label_point
CREATE OR REPLACE FUNCTION update_aerodrome_label_point() RETURNS void AS
$$
BEGIN
    UPDATE osm_aerodrome_label_point
    SET geometry = ST_Centroid(geometry)
    WHERE ST_GeometryType(geometry) <> 'ST_Point';

    UPDATE osm_aerodrome_label_point
    SET tags = update_tags(tags, geometry)
    WHERE COALESCE(tags->'name:latin', tags->'name:nonlatin', tags->'name_int') IS NULL;
END;
$$ LANGUAGE plpgsql;

SELECT update_aerodrome_label_point();

-- Handle updates

CREATE SCHEMA IF NOT EXISTS aerodrome_label;

CREATE TABLE IF NOT EXISTS aerodrome_label.updates
(
    id serial PRIMARY KEY,
    t  text,
    UNIQUE (t)
);
CREATE OR REPLACE FUNCTION aerodrome_label.flag() RETURNS trigger AS
$$
BEGIN
    INSERT INTO aerodrome_label.updates(t) VALUES ('y') ON CONFLICT(t) DO NOTHING;
    RETURN NULL;
END;
$$ LANGUAGE plpgsql;

CREATE OR REPLACE FUNCTION aerodrome_label.refresh() RETURNS trigger AS
$$
BEGIN
    RAISE LOG 'Refresh aerodrome_label';
    PERFORM update_aerodrome_label_point();
    -- noinspection SqlWithoutWhere
    DELETE FROM aerodrome_label.updates;
    RETURN NULL;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trigger_flag
    AFTER INSERT OR UPDATE OR DELETE
    ON osm_aerodrome_label_point
    FOR EACH STATEMENT
EXECUTE PROCEDURE aerodrome_label.flag();

CREATE CONSTRAINT TRIGGER trigger_refresh
    AFTER INSERT
    ON aerodrome_label.updates
    INITIALLY DEFERRED
    FOR EACH ROW
EXECUTE PROCEDURE aerodrome_label.refresh();