/**
 * Deletes cached capabilities that are no longer needed by the component.
 * Also unassigns these capabilities from any roles that have them.
 *
 * @param string $component examples: 'moodle', 'mod_forum', 'block_quiz_results'
 * @param array $newcapdef array of the new capability definitions that will be
 *                     compared with the cached capabilities
 * @return int number of deprecated capabilities that have been removed
 */
function capabilities_cleanup($component, $newcapdef = null)
{
    global $DB;
    $removedcount = 0;
    if ($cachedcaps = get_cached_capabilities($component)) {
        foreach ($cachedcaps as $cachedcap) {
            if (empty($newcapdef) || array_key_exists($cachedcap->name, $newcapdef) === false) {
                // Remove from capabilities cache.
                $DB->delete_records('capabilities', array('name' => $cachedcap->name));
                $removedcount++;
                // Delete from roles.
                if ($roles = get_roles_with_capability($cachedcap->name)) {
                    foreach ($roles as $role) {
                        if (!unassign_capability($cachedcap->name, $role->id)) {
                            print_error('cannotunassigncap', 'error', '', (object) array('cap' => $cachedcap->name, 'role' => $role->name));
                        }
                    }
                }
            }
            // End if.
        }
    }
    return $removedcount;
}

/**
 * Deletes cached capabilities that are no longer needed by the component.
 * Also unassigns these capabilities from any roles that have them.
 * @param $component - examples: 'moodle', 'mod/forum', 'block/quiz_results'
 * @param $newcapdef - array of the new capability definitions that will be
 *                     compared with the cached capabilities
 * @return int - number of deprecated capabilities that have been removed
 */
function capabilities_cleanup($component, $newcapdef = NULL)
{
    $removedcount = 0;
    if ($cachedcaps = get_cached_capabilities($component)) {
        foreach ($cachedcaps as $cachedcap) {
            if (empty($newcapdef) || array_key_exists($cachedcap->name, $newcapdef) === false) {
                // Remove from capabilities cache.
                if (!delete_records('capabilities', 'name', $cachedcap->name)) {
                    error('Could not delete deprecated capability ' . $cachedcap->name);
                } else {
                    $removedcount++;
                }
                // Delete from roles.
                if ($roles = get_roles_with_capability($cachedcap->name)) {
                    foreach ($roles as $role) {
                        if (!unassign_capability($cachedcap->name, $role->id)) {
                            error('Could not unassign deprecated capability ' . $cachedcap->name . ' from role ' . $role->name);
                        }
                    }
                }
            }
            // End if.
        }
    }
    return $removedcount;
}