https://community.elgg.org/plugins/879242 i want to make this plugin's action admin only so i make change in start.php file as below its take all right from non admin user but that start chat,add member link still visiblle to non admin how can hide that??? changed code is highlighted in BOld ,please help me

<?php
/**
 * Chat
 *
 * @package Chat
 */

/**
 * Initialize the plugin.
 */
function chat_init() {
    global $CONFIG;

    $actionspath = $CONFIG->pluginspath . "chat/actions/chat";
    elgg_register_action("chat/save", "$actionspath/save.php",'admin');
    elgg_register_action("chat/addmembers", "$actionspath/addmembers.php",'admin');
    elgg_register_action("chat/leave", "$actionspath/leave.php");
    elgg_register_action("chat/delete", "$actionspath/delete.php",'admin');
    elgg_register_action("chat/message/save", "$actionspath/message/save.php");
    elgg_register_action("chat/message/delete", "$actionspath/message/delete.php");
    elgg_register_action("chat/usersettings/save", "$actionspath/usersettings/save.php",'admin');

    $libpath = elgg_get_plugins_path() . 'chat/lib/chat.php';
    elgg_register_library('chat', $libpath);

    elgg_require_js('chat/chat');

    // Add custom CSS
    elgg_extend_view('css', 'chat/css');

    // Register on low priority so it's possible to remove items added by other plugins
    elgg_register_plugin_hook_handler('register', 'menu:entity', 'chat_entity_menu_setup', 600);
    // Register on low priority so it's possible to remove items added by other plugins
    elgg_register_plugin_hook_handler('register', 'menu:entity', 'chat_message_menu_setup', 600);
    elgg_register_plugin_hook_handler('permissions_check', 'object', 'chat_permissions_override');
    elgg_register_plugin_hook_handler('entity:url', 'object', 'chat_url_handler');

    elgg_register_event_handler('pagesetup', 'system', 'chat_notifier');

    elgg_register_page_handler('chat', 'chat_page_handler');
}

/**
 * Dispatche chat pages.
 *
 * @param array $page
 * @return bool
 */
function chat_page_handler ($page) {
    elgg_load_library('chat');

    if (!isset($page[0])) {
        elgg_push_breadcrumb(elgg_echo('chat'));
        $page[0] = 'all';
    } else {
        elgg_push_breadcrumb(elgg_echo('chat'), 'chat/all');
    }

    switch ($page[0]) {
        case 'messages':
            include(__DIR__ . '/messages.php');
            return true;
        case 'notifier':
            include(__DIR__ . '/notifier.php');
            return true;
        case 'owner':
            $user = get_user_by_username($page[1]);
            $params = chat_all($user->guid);
            break;
        case 'friends':
            $user = get_user_by_username($page[1]);
            $params = chat_friends($user->guid);
            break;
        case 'add':
            gatekeeper();
            $params = chat_edit();
            break;
        case 'edit':
            gatekeeper();
            $params = chat_edit($page[1]);
            break;
        case 'view':
            $params = chat_view($page[1]);
            break;
        case 'members':
            gatekeeper();
            $params = chat_add_members($page[1]);
            break;
        case 'all':
        default:
            $params = chat_all();
            break;
        }

    $body = elgg_view_layout('content', $params);
    echo elgg_view_page('test', $body);
    return true;
}

/**
 * Format and return the URL for chats.
 *
 * @param string $hook   'entity:url'
 * @param string $type   'object'
 * @param string $url    The current URL
 * @param array  $params Array('entity' => ElggObject)
 * @return string URL of the chat
 */
function chat_url_handler($hook, $type, $url, $params) {
    $entity = elgg_extract('entity', $params);

    if (!$entity instanceof ElggChat) {
        return $url;
    }

    $title = elgg_get_friendly_title($entity->title);

    return "chat/view/{$entity->guid}/$title";
}

/**
 * Add title button for adding more people to a chat.
 *
 * All members of the chat are allowed to add people.
 *
 * @todo Is it possible to use userpicker through lightbox?
 *
 * @param obj $entity ElggChat object
 */
function chat_register_addusers_button($entity) {
    if (elgg_is_logged_in()) {
        $user = elgg_get_logged_in_user_entity();

        if ($user && $entity->isMember()) {
            $guid = $entity->getGUID();
            elgg_register_menu_item('title', array(
                'name' => 'chat_members',
                'href' => "chat/members/$guid",
                'text' => elgg_echo('chat:members:add'),
                'link_class' => 'elgg-button elgg-button-action', // elgg-lightbox
            ));
        }

        /*
        elgg_load_js('lightbox');
        elgg_load_css('lightbox');

        elgg_load_js('elgg.userpicker');
        */
    }
}

/**
 * Set up the entity menu for chat entities.
 */
function chat_entity_menu_setup ($hook, $type, $return, $params) {
    if (elgg_in_context('widgets')) {
        return $return;
    }

    $entity = $params['entity'];
    $handler = elgg_extract('handler', $params, false);
    if ($handler != 'chat') {
        return $return;
    }

    $num_messages = $entity->getUnreadMessagesCount();
    if ($num_messages) {
        if ($num_messages == 1) {
            $string = 'chat:unread_message'; // Singular
        } else {
            $string = 'chat:unread_messages'; // Plural
        }

        $text = elgg_echo($string, array($num_messages));

        $options = array(
            'name' => 'unread_mesages',
            'text' => $text,
            'href' => false,
            'priority' => 150,
        );
        $return[] = ElggMenuItem::factory($options);
    }

    // Use white list to prevent unwanted menu items
    $allow = array('unread_mesages');
    if (!elgg_in_context('chat_preview')) {
        $allow[] = 'edit';
        $allow[] = 'delete';
    }

    // Remove unwanted menu items
    foreach ($return as $index => $item) {
        if (!in_array($item->getName(), $allow)) {
            unset($return[$index]);
        }
    }

    return $return;
}

/**
 * Set up the entity menu for chat messages.
 */
function chat_message_menu_setup ($hook, $type, $return, $params) {
    if (elgg_in_context('widgets')) {
        return $return;
    }

    $entity = $params['entity'];

    if ($entity->getSubtype() !== 'chat_message') {
        return $return;
    }

    // We don't want other plugins to add new menu items so we use a white list
    $allow = array('likes');

    $user = elgg_get_logged_in_user_entity();

    if ($entity->getOwnerGUID() == $user->getGUID() || $user->isAdmin()) {
        $guid = $entity->getGUID();

        $options = array(
            'name' => 'edit',
            'text' => elgg_echo('edit'),
            'href' => "#chat-edit-message-$guid",
            'priority' => 100,
            'rel' => 'toggle',
        );
        $return[] = ElggMenuItem::factory($options);

        $options = array(
            'name' => 'delete',
            'text' => elgg_view_icon('delete'),
            'href' => "action/chat/message/delete?guid=$guid",
            'priority' => 150,
            'is_action' => true,
        );
        $return[] = ElggMenuItem::factory($options);

        $allow[] = 'edit';
        $allow[] = 'delete';
    }

    // Remove unwanted menu items
    foreach ($return as $index => $item) {
        if (!in_array($item->getName(), $allow)) {
            unset($return[$index]);
        }
    }

    return $return;
}

/**
 * Display notification of new chat messages in topbar
 */
function chat_notifier() {
    if (elgg_is_logged_in()) {
        // Add hidden popup module to topbar
        elgg_extend_view('page/elements/topbar', 'chat/preview');

        $text = elgg_view_icon('speech-bubble-alt');

        $count = chat_count_unread_messages();
        if ($count) {
            $text .= "<span id=\"chat-messages-new\">$count</span>";
        } else {
            // Add a hidden element so value can be added using XHR
            $text .= "<span id=\"chat-messages-new\" class=\"hidden\"></span>";
        }

        // This link opens the popup module
        elgg_register_menu_item('topbar', array(
            'name' => 'chat-notifier',
            'href' => '#chat-messages-preview',
            'text' => $text,
            'priority' => 600,
            'title' => elgg_echo("chat:messages"),
            'rel' => 'popup',
            'id' => 'chat-preview-link',
        ));
    }
}

/**
 * Get all chats with unread messages.
 *
 * @param array $options See elgg_get_entities_from_annotations().
 */
function chat_get_unread_chats($options = array()) {
    $user = elgg_get_logged_in_user_entity();

    $defaults = array(
        'type' => 'object',
        'subtype' => 'chat',
        'annotation_names' => 'unread_messages',
        'annotation_owner_guids' => $user->getGUID(),
        'count' => false,
    );

    $options = array_merge($defaults, $options);

    return elgg_get_entities_from_annotations($options);
}

/**
 * Get the number of all unread chat messages.
 *
 * @return mixed False on error, int if success.
 */
function chat_count_unread_messages() {
    $user_guid = elgg_get_logged_in_user_guid();

    return elgg_get_entities_from_relationship(array(
        'type' => 'object',
        'subtype' => 'chat_message',
        'count' => true,
        'relationship' => 'unread',
        'relationship_guid' => $user_guid,
        'inverse_relationship' => true,
    ));
}

/**
 * Allow chat members to add messages to chat.
 */
function chat_permissions_override($hook, $type, $return, $params) {
    $entity = $params['entity'];
    $user = $params['user'];

    if (elgg_instanceof($entity, 'object', 'chat')) {
        // Allow full access to administrators
        if ($user->isAdmin()) {
            return true;
        }

        // Allow chat members to add messages to chat
        if ($entity->isMember($user) && elgg_in_context('chat_message')) {
            return true;
        }
    }

    return $return;
}

elgg_register_event_handler('init', 'system', 'chat_init');