private static function get_messagearea_contact_structure() {
        return new external_single_structure(
            array(
                'userid' => new external_value(PARAM_INT, 'The user\'s id'),
                'fullname' => new external_value(PARAM_NOTAGS, 'The user\'s name'),
                'profileimageurl' => new external_value(PARAM_URL, 'User picture URL'),
                'profileimageurlsmall' => new external_value(PARAM_URL, 'Small user picture URL'),
                'ismessaging' => new external_value(PARAM_BOOL, 'If we are messaging the user'),
                'sentfromcurrentuser' => new external_value(PARAM_BOOL, 'Was the last message sent from the current user?'),
                'lastmessage' => new external_value(PARAM_NOTAGS, 'The user\'s last message'),
                'lastmessagedate' => new external_value(PARAM_INT, 'Timestamp for last message', VALUE_DEFAULT, null),
                'messageid' => new external_value(PARAM_INT, 'The unique search message id', VALUE_DEFAULT, null),
                'showonlinestatus' => new external_value(PARAM_BOOL, 'Show the user\'s online status?'),
                'isonline' => new external_value(PARAM_BOOL, 'The user\'s online status'),
                'isread' => new external_value(PARAM_BOOL, 'If the user has read the message'),
                'isblocked' => new external_value(PARAM_BOOL, 'If the user has been blocked'),
                'unreadcount' => new external_value(PARAM_INT, 'The number of unread messages in this conversation',
                    VALUE_DEFAULT, null),
                'conversationid' => new external_value(PARAM_INT, 'The id of the conversation', VALUE_DEFAULT, null),
            )
        );
    }