/* 1. Loginseite
--------------------------------------------------------------------------------- */
// deaktiviert den Sprachwechsler
add_filter( 'login_display_language_dropdown', '__return_false');

// deaktiviert den "zurück zum Blog" Link
add_filter( 'login_site_html_link' , '__return_false' );

// passt die Fehlertextanzeige bei falschem Login an
function gw_custom_login_errors() {
  return 'Da passt etwas nicht.';
}
add_filter( 'login_errors', 'gw_custom_login_errors' );

/* 2. WordPress Adminbar
--------------------------------------------------------------------------------- */
// deaktiviert verschiedene Menüpunkte in der Adminbar
function gw_disable_adminbar_links() {
    global $wp_admin_bar;
    $wp_admin_bar->remove_menu('wp-logo');
    $wp_admin_bar->remove_menu('comments');
    $wp_admin_bar->remove_menu('new-content');
    $wp_admin_bar->remove_menu('themes');
    $wp_admin_bar->remove_menu('widgets');
    $wp_admin_bar->remove_menu('view-site');
    $wp_admin_bar->remove_menu('customize');
    $wp_admin_bar->remove_menu('menus');
    $wp_admin_bar->remove_menu('dashboard');
    $wp_admin_bar->remove_menu('edit-profile');
    $wp_admin_bar->remove_menu('user-info');
    $wp_admin_bar->remove_menu('search');
}
add_action( 'wp_before_admin_bar_render', 'gw_disable_adminbar_links' );

// löscht den Howdy Text in der Adminbar
function gw_remove_howdy($wp_admin_bar)
{
    $my_account = $wp_admin_bar->get_node('my-account');
    $greeting = str_replace('Willkommen,', '', $my_account->title);
    $wp_admin_bar->add_node([
        'id' => 'my-account',
        'title' => $greeting,
    ]);
}
add_filter( 'admin_bar_menu', 'gw_remove_howdy' );

/* 3. WordPress Dashboard Widgets
--------------------------------------------------------------------------------- */
// deaktiviert alle Dashboard Widgets
function gw_disable_dashboard_widgets()
{
    remove_action('welcome_panel', 'wp_welcome_panel');
    remove_meta_box('dashboard_primary', 'dashboard', 'side');
    remove_meta_box('dashboard_secondary', 'dashboard', 'side');
    remove_meta_box('dashboard_quick_press', 'dashboard', 'side');
    remove_meta_box('dashboard_recent_drafts', 'dashboard', 'side');
    remove_meta_box('dashboard_php_nag', 'dashboard', 'normal');
    remove_meta_box('dashboard_browser_nag', 'dashboard', 'normal');
    remove_meta_box('dashboard_site_health', 'dashboard', 'normal');
    remove_meta_box('health_check_status', 'dashboard', 'normal');
    remove_meta_box('dashboard_activity', 'dashboard', 'normal');
    remove_meta_box('dashboard_right_now', 'dashboard', 'normal');
    remove_meta_box('network_dashboard_right_now', 'dashboard', 'normal');
    remove_meta_box('dashboard_recent_comments', 'dashboard', 'normal');
    remove_meta_box('dashboard_incoming_links', 'dashboard', 'normal');
    remove_meta_box('dashboard_plugins', 'dashboard', 'normal');
}
add_action( 'wp_dashboard_setup', 'gw_disable_dashboard_widgets' );

// deaktiviert die Hilfe Box
function gw_remove_helpbox(){
    global $current_screen;
        $current_screen->remove_help_tabs();
}
add_filter( 'contextual_help_list','gw_remove_helpbox' );

// deaktiviert Anwendungspasswörter
add_filter( 'wp_is_application_passwords_available', '__return_false' );

/* 4. CSS Styles in WordPress Backend
--------------------------------------------------------------------------------- */
function gw_backend_styles() {
    if(is_admin()){
    echo '<style type="text/css">
            input#delete_all {
                background: red !important;
                color: white !important;
                border-color: red !important;
            }
          </style>';
    }
}
add_action('admin_head', 'gw_backend_styles');

// ändert anzeige unten im wp backend footer
function gw_change_wp_footer_text () {
echo '<span id="footer-thankyou">Entwickelt von <a href="https://galliweb.ch" target="_blank">Galli Web</a></span>';
}
add_filter( 'admin_footer_text', 'gw_change_wp_footer_text' );

/* 5. Clear WP Head
--------------------------------------------------------------------------------- */
add_filter( 'rest_enabled', '__return_false' );
add_filter( 'rest_jsonp_enabled', '__return_false' );
remove_action( 'wp_enqueue_scripts', 'wp_enqueue_global_styles' );
remove_action( 'wp_body_open', 'wp_global_styles_render_svg_filters' );
remove_action( 'wp_head', 'wp_generator' );
remove_action( 'wp_head', 'rsd_link' );
remove_action( 'wp_head', 'wlwmanifest_link' );
remove_action( 'wp_head', 'wp_shortlink_wp_head' );
remove_action( 'wp_head', 'rest_output_link_wp_head' );
remove_action( 'wp_head', 'wp_oembed_add_discovery_links' );
remove_action( 'wp_head', 'feed_links_extra', 3 );
remove_action( 'wp_head', 'feed_links', 2 );
remove_action( 'wp_head', 'wp_resource_hints', 2, 99 );
add_filter('xmlrpc_enabled', '__return_false');
remove_action('embed_head', 'rel_canonical');
add_filter('wpseo_canonical', '__return_false');

// Remove dashicons in frontend for unauthenticated users
function bs_dequeue_dashicons() {
    if ( ! is_user_logged_in() ) {
        wp_deregister_style( 'dashicons' );
        wp_deregister_style( 'wp-block-library' );
    }
}
add_action( 'wp_enqueue_scripts', 'bs_dequeue_dashicons' );

// entfernt jQuery Migrate im Frontend
function gw_remove_jquery_migrate($scripts)
{
    if (!is_admin() && isset($scripts->registered['jquery'])) {
        $script = $scripts->registered['jquery'];
        
        if ($script->deps) { // Check whether the script has any dependencies
            $script->deps = array_diff($script->deps, array(
                'jquery-migrate'
            ));
        }
    }
}
add_action( 'wp_default_scripts', 'gw_remove_jquery_migrate' );

// remove WP Version alltogether
// Pick out the version number from scripts and styles
function remove_version_from_style_js( $src ) {
    if ( strpos( $src, 'ver=' . get_bloginfo( 'version' ) ) )
    $src = remove_query_arg( 'ver', $src );
    return $src;
}
add_filter( 'style_loader_src', 'remove_version_from_style_js');
add_filter( 'script_loader_src', 'remove_version_from_style_js');

/* 6. Remove Emojis
--------------------------------------------------------------------------------- */
function disable_emojis() {
 remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
 remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
 remove_action( 'wp_print_styles', 'print_emoji_styles' );
 remove_action( 'admin_print_styles', 'print_emoji_styles' ); 
 remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
 remove_filter( 'comment_text_rss', 'wp_staticize_emoji' ); 
 remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );
 add_filter( 'tiny_mce_plugins', 'disable_emojis_tinymce' );
 add_filter( 'wp_resource_hints', 'disable_emojis_remove_dns_prefetch', 10, 2 );
}
add_action( 'init', 'disable_emojis' );

/**
 * Filter function used to remove the tinymce emoji plugin.
 * 
 * @param array $plugins 
 * @return array Difference betwen the two arrays
 */
function disable_emojis_tinymce( $plugins ) {
 if ( is_array( $plugins ) ) {
 return array_diff( $plugins, array( 'wpemoji' ) );
 } else {
 return array();
 }
}

/**
 * Remove emoji CDN hostname from DNS prefetching hints.
 *
 * @param array $urls URLs to print for resource hints.
 * @param string $relation_type The relation type the URLs are printed for.
 * @return array Difference betwen the two arrays.
 */
function disable_emojis_remove_dns_prefetch( $urls, $relation_type ) {
 if ( 'dns-prefetch' == $relation_type ) {
 /** This filter is documented in wp-includes/formatting.php */
 $emoji_svg_url = apply_filters( 'emoji_svg_url', 'https://s.w.org/images/core/emoji/2/svg/' );

$urls = array_diff( $urls, array( $emoji_svg_url ) );
 }

return $urls;
}