Use scriptmoduledata filter for Interactivity data

Use the 'scriptmoduledata_@wordpress/interactivity' filter to pass
Script Module data for the Interactivity API.

src/wp-includes/interactivity-api/class-wp-interactivity-api.php

@@ -138,22 +138,36 @@ public function config( string $store_namespace, array $config = array() ): arra
  * configuration will be available using a `getConfig` utility.
  *
  * @since 6.5.0
+ * @deprecated 6.6.0 Client data handle by the {@see "scriptmoduledata_{$module_id}"} filter.
  */
  public function print_client_interactivity_data() {
+ _deprecated_function( __METHOD__, '6.6.0' );
+ }
+
+ /**
+ * Set client-side interactivity data.
+ *
+ * Once in the browser, the state will be parsed and used to hydrate the client-side
+ * interactivity stores and the configuration will be available using a `getConfig` utility.
+ *
+ * @since 6.6.0
+ *
+ * @param array $data Data to filter.
+ * @return array Data for the Interactivity API script module.
+ */
+ public function filter_script_module_interactivity_data( array $data ): array {
  if ( empty( $this->state_data ) && empty( $this->config_data ) ) {
- return;
+ return $data;
  }
 
- $interactivity_data = array();
-
  $config = array();
  foreach ( $this->config_data as $key => $value ) {
  if ( ! empty( $value ) ) {
  $config[ $key ] = $value;
  }
  }
  if ( ! empty( $config ) ) {
- $interactivity_data['config'] = $config;
+ $data['config'] = $config;
  }
 
  $state = array();
@@ -163,52 +177,10 @@ public function print_client_interactivity_data() {
  }
  }
  if ( ! empty( $state ) ) {
- $interactivity_data['state'] = $state;
+ $data['state'] = $state;
  }
 
- if ( ! empty( $interactivity_data ) ) {
- /*
- * This data will be printed as JSON inside a script tag like this:
- * <script type="application/json"></script>
- *
- * A script tag must be closed by a sequence beginning with `</`. It's impossible to
- * close a script tag without using `<`. We ensure that `<` is escaped and `/` can
- * remain unescaped, so `</script>` will be printed as `\u003C/script\u00E3`.
- *
- * - JSON_HEX_TAG: All < and > are converted to \u003C and \u003E.
- * - JSON_UNESCAPED_SLASHES: Don't escape /.
- *
- * If the page will use UTF-8 encoding, it's safe to print unescaped unicode:
- *
- * - JSON_UNESCAPED_UNICODE: Encode multibyte Unicode characters literally (instead of as `\uXXXX`).
- * - JSON_UNESCAPED_LINE_TERMINATORS: The line terminators are kept unescaped when
- * JSON_UNESCAPED_UNICODE is supplied. It uses the same behaviour as it was
- * before PHP 7.1 without this constant. Available as of PHP 7.1.0.
- *
- * The JSON specification requires encoding in UTF-8, so if the generated HTML page
- * is not encoded in UTF-8 then it's not safe to include those literals. They must
- * be escaped to avoid encoding issues.
- *
- * @see https://www.rfc-editor.org/rfc/rfc8259.html for details on encoding requirements.
- * @see https://www.php.net/manual/en/json.constants.php for details on these constants.
- * @see https://html.spec.whatwg.org/#script-data-state for details on script tag parsing.
- */
- $json_encode_flags = JSON_HEX_TAG | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_LINE_TERMINATORS;
- if ( ! is_utf8_charset() ) {
- $json_encode_flags = JSON_HEX_TAG | JSON_UNESCAPED_SLASHES;
- }
-
- wp_print_inline_script_tag(
- wp_json_encode(
- $interactivity_data,
- $json_encode_flags
- ),
- array(
- 'type' => 'application/json',
- 'id' => 'wp-interactivity-data',
- )
- );
- }
+ return $data;
  }
 
  /**
@@ -235,13 +207,13 @@ public function register_script_modules() {
  * Adds the necessary hooks for the Interactivity API.
  *
  * @since 6.5.0
+ * @since 6.6.0 Use the {@see "scriptmoduledata_{$module_id}"} filter to pass client-side data.
  */
  public function add_hooks() {
  add_action( 'wp_enqueue_scripts', array( $this, 'register_script_modules' ) );
- add_action( 'wp_footer', array( $this, 'print_client_interactivity_data' ) );
-
  add_action( 'admin_enqueue_scripts', array( $this, 'register_script_modules' ) );
- add_action( 'admin_print_footer_scripts', array( $this, 'print_client_interactivity_data' ) );
+
+ add_filter( 'scriptmoduledata_@wordpress/interactivity', array( $this, 'filter_script_module_interactivity_data' ) );
  }
 
  /**