feat: automatically disable guest authors (#3345)

* feat: automatically disable guest authors

* feat: check again the presence of gas on cron

* Update includes/plugins/co-authors-plus/class-guest-contributor-role.php

Co-authored-by: Adam Cassis <adam@adamcassis.com>

---------

Co-authored-by: Adam Cassis <adam@adamcassis.com>

includes/plugins/co-authors-plus/class-guest-contributor-role.php

@@ -20,6 +20,8 @@
  *
  * This role can also be assigned to users who have other roles, so they can be assigned as co-authors of a post without having the capability to edit posts.
  * This is done via a custom UI in the user profile.
+ *
+ * CAP's Guest Authors feature will be disabled by default if there are no Guest Authors in the site. If you want to force enabling it, add the NEWSPACK_ENABLE_CAP_GUEST_AUTHORS constant to your wp-config.php file.
  */
 class Guest_Contributor_Role {
 	/**
@@ -38,19 +40,21 @@ class Guest_Contributor_Role {
 	 */
 	const SETTINGS_VERSION_OPTION_NAME = 'newspack_coauthors_plus_settings_version';
 
+	/**
+	 * The option where we store if the site has CAP's guest authors.
+	 */
+	const SITE_HAS_GUEST_AUTHORS_OPTION_NAME = 'newspack_check_site_has_cap_guest_authors';
+
 	/**
 	 * Initialize hooks and filters.
 	 */
-	public static function init() {
+	public static function initialize() {
 		add_filter( 'coauthors_edit_author_cap', [ __CLASS__, 'coauthors_edit_author_cap' ] );
 		add_action( 'admin_init', [ __CLASS__, 'setup_custom_role_and_capability' ] );
 		add_action( 'template_redirect', [ __CLASS__, 'prevent_myaccount_update' ] );
 		add_action( 'newspack_before_delete_account', [ __CLASS__, 'before_delete_account' ] );
 
-		if ( defined( 'NEWSPACK_DISABLE_CAP_GUEST_AUTHORS' ) && NEWSPACK_DISABLE_CAP_GUEST_AUTHORS ) {
-			add_filter( 'coauthors_guest_authors_enabled', '__return_false' );
-			add_action( 'admin_menu', [ __CLASS__, 'guest_author_menu_replacement' ] );
-		}
+		add_action( 'init', [ __CLASS__, 'early_init' ], 5 );
 
 		// Do not allow guest authors to login.
 		\add_filter( 'wp_authenticate_user', [ __CLASS__, 'wp_authenticate_user' ], 10, 2 );
@@ -79,6 +83,64 @@ public static function init() {
 
 		// Hide author email on the frontend, if it's a placeholder email.
 		\add_filter( 'theme_mod_show_author_email', [ __CLASS__, 'should_display_author_email' ] );
+
+		// Make sure we check again if the site has guest authors every hour.
+		$re_check_guest_authors = 'newspack_re_check_guest_authors';
+		if ( ! \wp_next_scheduled( $re_check_guest_authors ) ) {
+			\wp_schedule_event( time(), 'hourly', $re_check_guest_authors );
+		}
+		add_action( $re_check_guest_authors, [ __CLASS__, 'clear_site_has_cap_guest_authors_check' ] );
+	}
+
+	/**
+	 * Runs early in the init hook to make sure it runs before Co-Authors Plus initialization.
+	 *
+	 * @return void
+	 */
+	public static function early_init() {
+		if ( defined( 'NEWSPACK_ENABLE_CAP_GUEST_AUTHORS' ) && NEWSPACK_ENABLE_CAP_GUEST_AUTHORS ) {
+			return;
+		}
+		if ( ! self::site_has_cap_guest_authors() ) {
+			add_filter( 'coauthors_guest_authors_enabled', '__return_false' );
+			add_action( 'admin_menu', [ __CLASS__, 'guest_author_menu_replacement' ] );
+		}
+	}
+
+	/**
+	 * Clear the option that stores if the site has CAP's guest authors.
+	 * This will enforce a new check in the next request.
+	 * This will make sure we update the option if all guest authors are deleted.
+	 */
+	public static function clear_site_has_cap_guest_authors_check() {
+		if ( self::site_has_cap_guest_authors() ) {
+			delete_option( self::SITE_HAS_GUEST_AUTHORS_OPTION_NAME );
+		}
+	}
+
+	/**
+	 * Checks if the site has any guest authors. Will check it once in the database and store the result in an option.
+	 *
+	 * @return bool
+	 */
+	private static function site_has_cap_guest_authors() {
+		$response = get_option( self::SITE_HAS_GUEST_AUTHORS_OPTION_NAME );
+
+		// Only check in the database once.
+		if ( false === $response ) {
+			$query = new \WP_Query(
+				[
+					'post_type'      => 'guest-author',
+					'posts_per_page' => 1,
+					'post_status'    => 'any',
+					'fields'         => 'ids',
+				]
+			);
+			$response = $query->have_posts() ? 'yes' : 'no';
+			add_option( self::SITE_HAS_GUEST_AUTHORS_OPTION_NAME, $response, '', true );
+		}
+
+		return 'yes' === $response;
 	}
 
 	/**
@@ -488,4 +550,4 @@ public static function should_display_author_email( $value ) {
 		return $value;
 	}
 }
-Guest_Contributor_Role::init();
+Guest_Contributor_Role::initialize();