public function __construct( $theme_json = array(), $origin = 'theme' ) {
    if ( ! in_array( $origin, static::VALID_ORIGINS, true ) ) {
      $origin = 'theme';
    }

    $this->theme_json    = WP_Theme_JSON_Schema::migrate( $theme_json );
    $valid_block_names   = array_keys( static::get_blocks_metadata() );
    $valid_element_names = array_keys( static::ELEMENTS );
    $theme_json          = static::sanitize( $this->theme_json, $valid_block_names, $valid_element_names );
    $this->theme_json    = static::maybe_opt_in_into_settings( $theme_json );

    // Internally, presets are keyed by origin.
    $nodes = static::get_setting_nodes( $this->theme_json );
    foreach ( $nodes as $node ) {
      foreach ( static::PRESETS_METADATA as $preset_metadata ) {
        $path = $node['path'];
        foreach ( $preset_metadata['path'] as $subpath ) {
          $path[] = $subpath;
        }
        $preset = _wp_array_get( $this->theme_json, $path, null );
        if ( null !== $preset ) {
          // If the preset is not already keyed by origin.
          if ( isset( $preset[0] ) || empty( $preset ) ) {
            _wp_array_set( $this->theme_json, $path, array( $origin => $preset ) );
          }
        }
      }
    }
  }