CREATE FUNCTION _api.validate_text(
	_column TEXT DEFAULT '',
	_text TEXT DEFAULT NULL,
	_min INTEGER DEFAULT NULL,
	_max INTEGER DEFAULT NULL,
	_nullable BOOLEAN DEFAULT FALSE
)
RETURNS BOOLEAN
LANGUAGE plpgsql VOLATILE
AS $BODY$
DECLARE
	_length INTEGER;
BEGIN

	-- make sure that text can only be null
	-- when we allow it
	IF _text IS NULL AND NOT _nullable THEN
		PERFORM _api.raise(
			_msg => 'api_null_value',
			_detail => _column
		);
	END IF;

	IF _text IS NULL THEN
		RETURN TRUE;
	END IF;

	_length = LENGTH(_text);

	IF _min IS NOT NULL AND _length < _min THEN
		PERFORM _api.raise(
			_msg => 'api_text_min',
			_detail => _column,
			_hint => _min || ''
		);
	END IF;

	IF _max IS NOT NULL AND _length > _max THEN
		PERFORM _api.raise(
			_msg => 'api_text_max',
			_detail => _column,
			_hint => _max || ''
		);
	END IF;

	RETURN TRUE;
END
$BODY$;

GRANT EXECUTE ON FUNCTION _api.validate_text(TEXT, TEXT, INTEGER, INTEGER, BOOLEAN)
	TO rest_anon, rest_user;