[wpkama embed] https://wp-kama.com/2489 Multisite_Admin_Bar

Customize_Admin_Bar

/**
 * Сutomize multisite admin bar.
 * Moves default nested multisite menu to main toolbar menu.
 */
class Multisite_Admin_Bar {

	public static function init(): void {
		add_action( 'admin_bar_menu', [ __CLASS__, 'cutomize_toolbar' ], 31 ); // 31 - after `wp_admin_bar_site_menu()`
		add_action( 'wp_head', [ __CLASS__, 'styles' ] );
		add_action( 'admin_head', [ __CLASS__, 'styles' ] );

		add_action( 'admin_bar_menu', [ __CLASS__, 'add_switch_node' ], 30 );
	}

	public static function styles(): void {
		?>
		<style id="cutomize_multisite_admin_bar">
			#wp-admin-bar-network-admin .ab-icon:before{ color:#797c7d; } /* the color of the main icon */
			#wpadminbar .hl-current-blog{ background-color: rgba(255 255 255 / 0.15); }
		</style>
		<?php
	}

	public static function cutomize_toolbar( \WP_Admin_Bar $toolbar ): void {
		// for multisite only
		if( ! $toolbar->get_node( 'site-name' ) ){
			return;
		}

		// remove Multisite Language Switcher hook
		remove_action( 'admin_bar_menu', [ \lloc\Msls\MslsPlugin::class, 'update_adminbar' ], 999 );

		// NOTE: the closure needed to access `WP_Admin_Bar->nodes` private property
		$callback = function(){
			/** @var \WP_Admin_Bar $this */

			/// remove nodes
			unset(
				$this->nodes['site-name'], // default current site node
				$this->nodes['my-sites-super-admin'],
				$this->nodes['my-sites'],
				$this->nodes['my-sites-list']
			);

			/// network-admin
			$net_admin = & $this->nodes['network-admin'];
			$net_admin->parent = '';
			$net_admin->title = '<span class="ab-icon dashicons-admin-multisite"></span><span class="ab-label">Network</span>';

			/// blogs
			foreach( $this->nodes as $key => $node ){

				preg_match( '/blog-(\d+)(?:-(\w+))?/', $node->id, $mm );
				$blog_id = (int) ( $mm[1] ?? 0 );
				$type    = $mm[2] ?? '';

				if( $blog_id ){
					// main: blog-1, blog-2
					if( ! $type ){
						// title
						preg_match( '~^<.*>~', $node->title, $mm );
						$lang = langdata()->blog_id_lang( $blog_id );
						$title_icon_html = $mm[0] ?? '';
						$flag_img = sprintf( '<img src="%s" alt="%s">', langdata()->flag_url( $lang ), $lang );
						$node->title = $title_icon_html . $flag_img . '&nbsp;' . strtoupper( $lang );

						$node->href = is_admin() ? get_home_url( $blog_id ) : $node->href;
						$node->parent = '';
						$node->meta['class'] = ( get_current_blog_id() === $blog_id ) ? 'hl-current-blog' : '';
					}

					// comments: blog-1-c, blog-2-c
					if( 'c' === $type ){
						unset( $this->nodes[ $key ] );
					}
				}

			}

		};

		$callback->call( $toolbar );
	}

	public static function add_switch_node( \WP_Admin_Bar $toolbar ): void {
		global $pagenow;
		$url = $_SERVER['REQUEST_URI'];

		$url = str_starts_with( $url, '/ru' ) ? preg_replace( '~^/ru~', '', $url ) : "/ru$url";

		if( 'post.php' === $pagenow && ( $post_id = (int) ( $_GET['post'] ?? 0 ) ) ){
			$other_post_id = is_ru() ? get_ru_en_post_id( $post_id ) : get_en_ru_post_id( $post_id );
			$url = $other_post_id
				? str_replace( "post=$post_id", "post=$other_post_id", $url )
				: '';
		}

		$toolbar->add_menu( [
			'id'    => 'switch_langs',
			'title' => '<span class="ab-icon dashicons-controls-repeat"></span>',
			'href'  => $url,
			'meta'  => [
				'title' => 'Switch Curent Page to Opposite Lang',
				'onclick' => 'alert("aaaaaaaaa")',
			],
		] );
	}

}