32 

    33 	/**

    34 	 * Tracks whether the @wordpress/a11y script module is available.

    35 	 *

    36 	 * Some additional HTML is required on the page for the module to work. Track

    37 	 * whether it's available to print at the appropriate time.

    38 	 *

    39 	 * @since 6.7.0

    40 	 * @var bool

    41 	 */

    42 	private $a11y_available = false;

   196 

   197 		add_action( 'wp_footer', array( $this, 'print_script_module_data' ) );

   198 		add_action( 'admin_print_footer_scripts', array( $this, 'print_script_module_data' ) );

   199 		add_action( 'wp_footer', array( $this, 'print_a11y_script_module_html' ), 20 );

   200 		add_action( 'admin_print_footer_scripts', array( $this, 'print_a11y_script_module_html' ), 20 );

   366 

   367 	/**

   368 	 * Print data associated with Script Modules.

   369 	 *

   370 	 * The data will be embedded in the page HTML and can be read by Script Modules on page load.

   371 	 *

   372 	 * @since 6.7.0

   373 	 *

   374 	 * Data can be associated with a Script Module via the

   375 	 * {@see "script_module_data_{$module_id}"} filter.

   376 	 *

   377 	 * The data for a Script Module will be serialized as JSON in a script tag with an ID of the

   378 	 * form `wp-script-module-data-{$module_id}`.

   379 	 */

   380 	public function print_script_module_data(): void {

   381 		$modules = array();

   382 		foreach ( array_keys( $this->get_marked_for_enqueue() ) as $id ) {

   383 			if ( '@wordpress/a11y' === $id ) {

   384 				$this->a11y_available = true;

   385 			}

   386 			$modules[ $id ] = true;

   387 		}

   388 		foreach ( array_keys( $this->get_import_map()['imports'] ) as $id ) {

   389 			if ( '@wordpress/a11y' === $id ) {

   390 				$this->a11y_available = true;

   391 			}

   392 			$modules[ $id ] = true;

   393 		}

   394 

   395 		foreach ( array_keys( $modules ) as $module_id ) {

   396 			/**

   397 			 * Filters data associated with a given Script Module.

   398 			 *

   399 			 * Script Modules may require data that is required for initialization or is essential

   400 			 * to have immediately available on page load. These are suitable use cases for

   401 			 * this data.

   402 			 *

   403 			 * The dynamic portion of the hook name, `$module_id`, refers to the Script Module ID

   404 			 * that the data is associated with.

   405 			 *

   406 			 * This is best suited to pass essential data that must be available to the module for

   407 			 * initialization or immediately on page load. It does not replace the REST API or

   408 			 * fetching data from the client.

   409 			 *

   410 			 * Example:

   411 			 *

   412 			 *     add_filter(

   413 			 *         'script_module_data_MyScriptModuleID',

   414 			 *         function ( array $data ): array {

   415 			 *             $data['dataForClient'] = 'ok';

   416 			 *             return $data;

   417 			 *         }

   418 			 *     );

   419 			 *

   420 			 * If the filter returns no data (an empty array), nothing will be embedded in the page.

   421 			 *

   422 			 * The data for a given Script Module, if provided, will be JSON serialized in a script

   423 			 * tag with an ID of the form `wp-script-module-data-{$module_id}`.

   424 			 *

   425 			 * The data can be read on the client with a pattern like this:

   426 			 *

   427 			 * Example:

   428 			 *

   429 			 *     const dataContainer = document.getElementById( 'wp-script-module-data-MyScriptModuleID' );

   430 			 *     let data = {};

   431 			 *     if ( dataContainer ) {

   432 			 *         try {

   433 			 *             data = JSON.parse( dataContainer.textContent );

   434 			 *         } catch {}

   435 			 *     }

   436 			 *     // data.dataForClient === 'ok';

   437 			 *     initMyScriptModuleWithData( data );

   438 			 *

   439 			 * @since 6.7.0

   440 			 *

   441 			 * @param array $data The data associated with the Script Module.

   442 			 */

   443 			$data = apply_filters( "script_module_data_{$module_id}", array() );

   444 

   445 			if ( is_array( $data ) && array() !== $data ) {

   446 				/*

   447 				 * This data will be printed as JSON inside a script tag like this:

   448 				 *   <script type="application/json"></script>

   449 				 *

   450 				 * A script tag must be closed by a sequence beginning with `</`. It's impossible to

   451 				 * close a script tag without using `<`. We ensure that `<` is escaped and `/` can

   452 				 * remain unescaped, so `</script>` will be printed as `\u003C/script\u00E3`.

   453 				 *

   454 				 *   - JSON_HEX_TAG: All < and > are converted to \u003C and \u003E.

   455 				 *   - JSON_UNESCAPED_SLASHES: Don't escape /.

   456 				 *

   457 				 * If the page will use UTF-8 encoding, it's safe to print unescaped unicode:

   458 				 *

   459 				 *   - JSON_UNESCAPED_UNICODE: Encode multibyte Unicode characters literally (instead of as `\uXXXX`).

   460 				 *   - JSON_UNESCAPED_LINE_TERMINATORS: The line terminators are kept unescaped when

   461 				 *     JSON_UNESCAPED_UNICODE is supplied. It uses the same behaviour as it was

   462 				 *     before PHP 7.1 without this constant. Available as of PHP 7.1.0.

   463 				 *

   464 				 * The JSON specification requires encoding in UTF-8, so if the generated HTML page

   465 				 * is not encoded in UTF-8 then it's not safe to include those literals. They must

   466 				 * be escaped to avoid encoding issues.

   467 				 *

   468 				 * @see https://www.rfc-editor.org/rfc/rfc8259.html for details on encoding requirements.

   469 				 * @see https://www.php.net/manual/en/json.constants.php for details on these constants.

   470 				 * @see https://html.spec.whatwg.org/#script-data-state for details on script tag parsing.

   471 				 */

   472 				$json_encode_flags = JSON_HEX_TAG | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_LINE_TERMINATORS;

   473 				if ( ! is_utf8_charset() ) {

   474 					$json_encode_flags = JSON_HEX_TAG | JSON_UNESCAPED_SLASHES;

   475 				}

   476 

   477 				wp_print_inline_script_tag(

   478 					wp_json_encode(

   479 						$data,

   480 						$json_encode_flags

   481 					),

   482 					array(

   483 						'type' => 'application/json',

   484 						'id'   => "wp-script-module-data-{$module_id}",

   485 					)

   486 				);

   487 			}

   488 		}

   489 	}

   490 

   491 	/**

   492 	 * @access private This is only intended to be called by the registered actions.

   493 	 *

   494 	 * @since 6.7.0

   495 	 */

   496 	public function print_a11y_script_module_html() {

   497 		if ( ! $this->a11y_available ) {

   498 			return;

   499 		}

   500 		echo '<div style="position:absolute;margin:-1px;padding:0;height:1px;width:1px;overflow:hidden;clip-path:inset(50%);border:0;word-wrap:normal !important;">'

   501 			. '<p id="a11y-speak-intro-text" class="a11y-speak-intro-text" hidden>' . esc_html__( 'Notifications' ) . '</p>'

   502 			. '<div id="a11y-speak-assertive" class="a11y-speak-region" aria-live="assertive" aria-relevant="additions text" aria-atomic="true"></div>'

   503 			. '<div id="a11y-speak-polite" class="a11y-speak-region" aria-live="polite" aria-relevant="additions text" aria-atomic="true"></div>'

   504 			. '</div>';

   505 	}