WIP - create global navbar in jetpack-mu-wpcom

projects/packages/jetpack-mu-wpcom/src/class-jetpack-mu-wpcom.php

@@ -75,6 +75,8 @@ public static function load_features() {
 		require_once __DIR__ . '/features/media/heif-support.php';
 
 		require_once __DIR__ . '/features/block-patterns/block-patterns.php';
+
+		require_once __DIR__ . '/features/global-nav-bar/global-nav.php';
 	}
 
 	/**

projects/packages/jetpack-mu-wpcom/src/features/global-nav-bar/class-wpcom-global-nav.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * WPCOM Global Navbar Class
+ *
+ * @package automattic/jetpack-mu-wpcom
+ */
+
+/**
+ * Provides custom admin bar instead of the default WordPress admin bar.
+ */
+class WPcom_Global_Nav {
+
+	/**
+	 * Constructor
+	 */
+	public function __construct() {
+		add_action( 'admin_bar_init', array( $this, 'init' ) );
+	}
+
+	/**
+	 * Initialize our masterbar.
+	 */
+	public function init() {
+		add_action( 'wp_before_admin_bar_render', array( $this, 'update_core_masterbar' ), 99999 );
+	}
+
+	/**
+	 * Update and add items on the core masterbar.
+	 */
+	public function update_core_masterbar() {
+		global $wp_admin_bar;
+
+		if ( ! is_object( $wp_admin_bar ) ) {
+			return false;
+		}
+
+		$nodes = array();
+
+		// First, lets gather all nodes and remove them.
+		foreach ( $wp_admin_bar->get_nodes() as $node ) {
+			$nodes[ $node->id ] = $node;
+			$wp_admin_bar->remove_node( $node->id );
+		}
+
+		// Add custom groups and menus here
+
+		// Re-add original nodes
+		foreach ( $nodes as $id => $node ) {
+			$wp_admin_bar->add_node( $node );
+		}
+	}
+}

projects/packages/jetpack-mu-wpcom/src/features/global-nav-bar/global-nav.php

@@ -0,0 +1,22 @@
+<?php
+/**
+ * WPCOM Global Navbar Loader
+ *
+ * @package automattic/jetpack-mu-wpcom
+ */
+
+require __DIR__ . '/class-wpcom-global-nav.php';
+
+/**
+ * Determine if new global nav should be loaded.
+ */
+function should_use_new_global_nav() {
+	// True for the sake of simplicity in testing this right now. We may want to check a user
+	// setting or meta here.
+	return true;
+}
+add_filter( 'wpcom_global_nav_enabled', 'should_use_new_global_nav' );
+
+if ( should_use_new_global_nav() ) {
+	new WPcom_Global_Nav();
+}

projects/plugins/jetpack/modules/masterbar.php

@@ -22,7 +22,9 @@
 require __DIR__ . '/masterbar/admin-color-schemes/class-admin-color-schemes.php';
 require __DIR__ . '/masterbar/inline-help/class-inline-help.php';
 
-new Masterbar();
+if ( ! apply_filters( 'wpcom_global_nav_enabled', false ) ) {
+	new Masterbar();
+}
 new Admin_Color_Schemes();
 
 if ( ( new Host() )->is_woa_site() ) {