DROP PROCEDURE IF EXISTS account.role_getDescendents;

DELIMITER $$
CREATE DEFINER=`root`@`%` PROCEDURE `account`.`role_getDescendents`(vSelf INT)
BEGIN
/**
 * Gets the identifiers of all the subroles implemented by a role (Including
 * itself).
 *
 * @param vSelf The role identifier
 * @table tmp.role Subroles implemented by the role
 */
	DECLARE vIsRoot BOOL;

	DROP TEMPORARY TABLE IF EXISTS
		tmp.role, parents, childs;

	CREATE TEMPORARY TABLE tmp.role
		(UNIQUE (id))
		ENGINE = MEMORY
		SELECT vSelf AS id;

	CREATE TEMPORARY TABLE parents
		ENGINE = MEMORY
		SELECT vSelf AS id;

	CREATE TEMPORARY TABLE childs
		LIKE parents;

	REPEAT
		DELETE FROM childs;
		INSERT INTO childs
			SELECT DISTINCT r.inheritsFrom id
				FROM parents p
					JOIN roleInherit r ON r.role = p.id
					LEFT JOIN tmp.role t ON t.id = r.inheritsFrom
				WHERE t.id IS NULL;

		DELETE FROM parents;
		INSERT INTO parents
			SELECT * FROM childs;

		INSERT INTO tmp.role
			SELECT * FROM childs;

		UNTIL ROW_COUNT() <= 0
	END REPEAT;

	-- If it is root all the roles are added

	SELECT COUNT(*) > 0 INTO vIsRoot
		FROM tmp.role t
			JOIN role r ON r.id = t.id 
		WHERE r.`name` = 'root';
		
	IF vIsRoot THEN
		INSERT IGNORE INTO tmp.role (id)
			SELECT id FROM role;
	END IF;

	-- Cleaning

	DROP TEMPORARY TABLE
		parents, childs;
END$$
DELIMITER ;