public static function delete_message($messageid, $userid, $read = true) {
        global $CFG;

        // Check if private messaging between users is allowed.
        if (empty($CFG->messaging)) {
            throw new moodle_exception('disabled', 'message');
        }

        // Warnings array, it can be empty at the end but is mandatory.
        $warnings = array();

        // Validate params.
        $params = array(
            'messageid' => $messageid,
            'userid' => $userid,
            'read' => $read
        );
        $params = self::validate_parameters(self::delete_message_parameters(), $params);

        // Validate context.
        $context = context_system::instance();
        self::validate_context($context);

        $user = core_user::get_user($params['userid'], '*', MUST_EXIST);
        core_user::require_active_user($user);

        if (\core_message\api::can_delete_message($user->id, $params['messageid'])) {
            $status = \core_message\api::delete_message($user->id, $params['messageid']);
        } else {
            throw new moodle_exception('You do not have permission to delete this message');
        }

        $results = array(
            'status' => $status,
            'warnings' => $warnings
        );
        return $results;
    }