ays it will use the numeric indexes for replacement.
		 * We rather replace the existing with the incoming value, if it exists.
		 * This is the case of spacing.units.
		 *
		 * For leaf values that are associative arrays it will merge them as expected.
		 * This is also not the behavior we want for the current associative arrays (presets).
		 * We rather replace the existing with the incoming value, if it exists.
		 * This happens, for example, when we merge data from theme.json upon existing
		 * theme supports or when we merge anything coming from the same source twice.
		 * This is the case of color.palette, color.gradients, color.duotone,
		 * typography.fontSizes, or typography.fontFamilies.
		 *
		 * Additionally, for some preset types, we also want to make sure the
		 * values they introduce don't conflict with default values. We do so
		 * by checking the incoming slugs for theme presets and compare them
		 * with the equivalent default presets: if a slug is present as a default
		 * we remove it from the theme presets.
		 */
		$nodes        = static::get_setting_nodes( $incoming_data );
		$slugs_global = static::get_default_slugs( $this->theme_json, array( 'settings' ) );
		foreach ( $nodes as $node ) {
			$slugs_node = static::get_default_slugs( $this->theme_json, $node['path'] );
			$slugs      = array_merge_recursive( $slugs_global, $slugs_node );

			// Replace the spacing.units.
			$path    = array_merge( $node['path'], array( 'spacing', 'units' ) );
			$content = _wp_array_get( $incoming_data, $path, null );
			if ( isset( $content ) ) {
				_wp_array_set( $this->theme_json, $path, $content );
			}

			// Replace the presets.
			foreach ( static::PRESETS_METADATA as $preset ) {
				$override_preset = ! static::get_metadata_boolean( $this->theme_json['settings'], $preset['prevent_override'], true );

				foreach ( static::VALID_ORIGINS as $origin ) {
					$base_path = array_merge( $node['path'], $preset['path'] );
					$path      = array_merge( $base_path, array( $origin ) );
					$content   = _wp_array_get( $incoming_data, $path, null );
					if ( ! isset( $content ) ) {
						continue;
					}

					if ( 'theme' === $origin && $preset['use_default_names'] ) {
						foreach ( $content as &$item ) {
							if ( ! array_key_exists( 'name', $item ) ) {
								$name = static::get_name_from_defaults( $item['slug'], $base_path );
								if ( null !== $name ) {
									$item['name'] = $name;
								}
							}
						}
					}

					if (
						( 'theme' !== $origin ) ||
						( 'theme' === $origin && $override_preset )
					) {
						_wp_array_set( $this->theme_json, $path, $content );
					} else {
						$slugs_for_preset = _wp_array_get( $slugs, $preset['path'], array() );
						$content          = static::filter_slugs( $content, $slugs_for_preset );
						_wp_array_set( $this->theme_json, $path, $content );
					}
				}
			}
		}
	}

	/**
	 * Converts all filter (duotone) presets into SVGs.
	 *
	 * @since 5.9.1
	 *
	 * @param array $origins List of origins to process.
	 * @return string SVG filters.
	 */
	public function get_svg_filters( $origins ) {
		$blocks_metadata = static::get_blocks_metadata();
		$setting_nodes   = static::get_setting_nodes( $this->theme_json, $blocks_metadata );

		$filters = '';
		foreach ( $setting_nodes as $metadata ) {
			$node = _wp_array_get( $this->theme_json, $metadata['path'], array() );
			if ( empty( $node['color']['duotone'] ) ) {
				continue;
			}

			$duotone_presets = $node['color']['duotone'];

			foreach ( $origins as $origin ) {
				if ( ! isset( $duotone_presets[ $origin ] ) ) {
					continue;
				}
				foreach ( $duotone_presets[ $origin ] as $duotone_preset ) {
					$filters .= wp_get_duotone_filter_svg( $duotone_preset );
				}
			}
		}

		return $filters;
	}

	/**
	 * Returns whether a presets should be overridden or not.
	 *
	 * @since 5.9.0
	 * @deprecated 6.0.0 Use {@see 'get_metadata_boolean'} instead.
	 *
	 * @param array      $theme_json The theme.json like structure to inspect.
	 * @param array      $path       Path to inspect.
	 * @param bool|array $override   Data to compute whether to override the preset.
	 * @return boolean
	 */
	protected static function should_override_preset( $theme_json, $path, $override ) {
		_deprecated_function( __METHOD__, '6.0.0', 'get_metadata_boolean' );

		if ( is_bool( $override ) ) {
			return $override;
		}

		/*
		 * The relationship between whether to override the defaults
		 * and whether the defaults are enabled is inverse:
		 *
		 * - If defaults are enabled  => theme presets should not be overridden
		 * - If defaults are disabled => theme presets should be overridden
		 *
		 * For example, a theme sets defaultPalette to false,
		 * making the default palette hidden from the user.
		 * In that case, we want all the theme presets to be present,
		 * so they should override the defaults.
		 */
		if ( is_array( $override ) ) {
			$value = _wp_array_get( $theme_json, array_merge( $path, $override ) );
			if ( isset( $value ) ) {
				return ! $value;
			}

			// Search the top-level key if none was found for this node.
			$value = _wp_array_get( $theme_json, array_merge( array( 'settings' ), $override ) );
			if ( isset( $value ) ) {
				return ! $value;
			}

			return true;
		}
	}

	/**
	 * Returns the default slugs for all the presets in an associative array
	 * whose keys are the preset paths and the leafs is the list of slugs.
	 *
	 * For example:
	 *
	 *  array(
	 *   'color' => array(
	 *     'palette'   => array( 'slug-1', 'slug-2' ),
	 *     'gradients' => array( 'slug-3', 'slug-4' ),
	 *   ),
	 * )
	 *
	 * @since 5.9.0
	 *
	 * @param array $data      A theme.json like structure.
	 * @param array $node_path The path to inspect. It's 'settings' by default.
	 * @return array
	 */
	protected static function get_default_slugs( $data, $node_path ) {
		$slugs = array();

		foreach ( static::PRESETS_METADATA as $metadata ) {
			$path   = array_merge( $node_path, $metadata['path'], array( 'default' ) );
			$preset = _wp_array_get( $data, $path, null );
			if ( ! isset( $preset ) ) {
				continue;
			}

			$slugs_for_preset = array();
			$slugs_for_preset = array_map(
				static function( $value ) {
					return isset( $value['slug'] ) ? $value['slug'] : null;
				},
				$preset
			);
			_wp_array_set( $slugs, $metadata['path'], $slugs_for_preset );
		}

		return $slugs;
	}

	/**
	 * Get a `default`'s preset name by a provided slug.
	 *
	 * @since 5.9.0
	 *
	 * @param string $slug The slug we want to find a match from default presets.
	 * @param array  $base_path The path to inspect. It's 'settings' by default.
	 * @return string|null
	 */
	protected function get_name_from_defaults( $slug, $base_path ) {
		$path            = array_merge( $base_path, array( 'default' ) );
		$default_content = _wp_array_get( $this->theme_json, $path, null );
		if ( ! $default_content ) {
			return null;
		}
		foreach ( $default_content as $item ) {
			if ( $slug === $item['slug'] ) {
				return $item['name'];
			}
		}
		return null;
	}

	/**
	 * Removes the preset values whose slug is equal to any of given slugs.
	 *
	 * @since 5.9.0
	 *
	 * @param array $node  The node with the presets to validate.
	 * @param array $slugs The slugs that should not be overridden.
	 * @return array The new node.
	 */
	protected static function filter_slugs( $node, $slugs ) {
		if ( empty( $slugs ) ) {
			return $node;
		}

		$new_node = array();
		foreach ( $node as $value ) {
			if ( isset( $value['slug'] ) && ! in_array( $value['slug'], $slugs, true ) ) {
				$new_node[] = $value;
			}
		}

		return $new_node;
	}

	/**
	 * Removes insecure data from theme.json.
	 *
	 * @since 5.9.0
	 *
	 * @param array $theme_json Structure to sanitize.
	 * @return array Sanitized structure.
	 */
	public static function remove_insecure_properties( $theme_json ) {
		$sanitized = array();

		$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( $theme_json, $valid_block_names, $valid_element_names );

		$blocks_metadata = static::get_blocks_metadata();
		$style_nodes     = static::get_style_nodes( $theme_json, $blocks_metadata );
		foreach ( $style_nodes as $metadata ) {
			$input = _wp_array_get( $theme_json, $metadata['path'], array() );
			if ( empty( $input ) ) {
				continue;
			}

			$output = static::remove_insecure_styles( $input );
			if ( ! empty( $output ) ) {
				_wp_array_set( $sanitized, $metadata['path'], $output );
			}
		}

		$setting_nodes = static::get_setting_nodes( $theme_json );
		foreach ( $setting_nodes as $metadata ) {
			$input = _wp_array_get( $theme_json, $metadata['path'], array() );
			if ( empty( $input ) ) {
				continue;
			}

			$output = static::remove_insecure_settings( $input );
			if ( ! empty( $output ) ) {
				_wp_array_set( $sanitized, $metadata['path'], $output );
			}
		}

		if ( empty( $sanitized['styles'] ) ) {
			unset( $theme_json['styles'] );
		} else {
			$theme_json['styles'] = $sanitized['styles'];
		}

		if ( empty( $sanitized['settings'] ) ) {
			unset( $theme_json['settings'] );
		} else {
			$theme_json['settings'] = $sanitized['settings'];
		}

		return $theme_json;
	}

	/**
	 * Processes a setting node and returns the same node
	 * without the insecure settings.
	 *
	 * @since 5.9.0
	 *
	 * @param array $input Node to process.
	 * @return array
	 */
	protected static function remove_insecure_settings( $input ) {
		$output = array();
		foreach ( static::PRESETS_METADATA as $preset_metadata ) {
			foreach ( static::VALID_ORIGINS as $origin ) {
				$path_with_origin = array_merge( $preset_metadata['path'], array( $origin ) );
				$presets          = _wp_array_get( $input, $path_with_origin, null );
				if ( null === $presets ) {
					continue;
				}

				$escaped_preset = array();
				foreach ( $presets as $preset ) {
					if (
						esc_attr( esc_html( $preset['name'] ) ) === $preset['name'] &&
						sanitize_html_class( $preset['slug'] ) === $preset['slug']
					) {
						$value = null;
						if ( isset( $preset_metadata['value_key'], $preset[ $preset_metadata['value_key'] ] ) ) {
							$value = $preset[ $preset_metadata['value_key'] ];
						} elseif (
							isset( $preset_metadata['value_func'] ) &&
							is_callable( $preset_metadata['value_func'] )
						) {
							$value = call_user_func( $preset_metadata['value_func'], $preset );
						}

						$preset_is_valid = true;
						foreach ( $preset_metadata['properties'] as $property ) {
							if ( ! static::is_safe_css_declaration( $property, $value ) ) {
								$preset_is_valid = false;
								break;
							}
						}

						if ( $preset_is_valid ) {
							$escaped_preset[] = $preset;
						}
					}
				}

				if ( ! empty( $escaped_preset ) ) {
					_wp_array_set( $output, $path_with_origin, $escaped_preset );
				}
			}
		}
		return $output;
	}

	/**
	 * Processes a style node and returns the same node
	 * without the insecure styles.
	 *
	 * @since 5.9.0
	 *
	 * @param array $input Node to process.
	 * @return array
	 */
	protected static function remove_insecure_styles( $input ) {
		$output       = array();
		$declarations = static::compute_style_properties( $input );

		foreach ( $declarations as $declaration ) {
			if ( static::is_safe_css_declaration( $declaration['name'], $declaration['value'] ) ) {
				$path = static::PROPERTIES_METADATA[ $declaration['name'] ];

				// Check the value isn't an array before adding so as to not
				// double up shorthand and longhand styles.
				$value = _wp_array_get( $input, $path, array() );
				if ( ! is_array( $value ) ) {
					_wp_array_set( $output, $path, $value );
				}
			}
		}
		return $output;
	}

	/**
	 * Checks that a declaration provided by the user is safe.
	 *
	 * @since 5.9.0
	 *
	 * @param string $property_name  Property name in a CSS declaration, i.e. the `color` in `color: red`.
	 * @param string $property_value Value in a CSS declaration, i.e. the `red` in `color: red`.
	 * @return bool
	 */
	protected static function is_safe_css_declaration( $property_name, $property_value ) {
		$style_to_validate = $property_name . ': ' . $property_value;
		$filtered          = esc_html( safecss_filter_attr( $style_to_validate ) );
		return ! empty( trim( $filtered ) );
	}

	/**
	 * Returns the raw data.
	 *
	 * @since 5.8.0
	 *
	 * @return array Raw data.
	 */
	public function get_raw_data() {
		return $this->theme_json;
	}

	/**
	 * Transforms the given editor settings according the
	 * add_theme_support format to the theme.json format.
	 *
	 * @since 5.8.0
	 *
	 * @param array $settings Existing editor settings.
	 * @return array Config that adheres to the theme.json schema.
	 */
	public static function get_from_editor_settings( $settings ) {
		$theme_settings = array(
			'version'  => static::LATEST_SCHEMA,
			'settings' => array(),
		);

		// Deprecated theme supports.
		if ( isset( $settings['disableCustomColors'] ) ) {
			if ( ! isset( $theme_settings['settings']['color'] ) ) {
				$theme_settings['settings']['color'] = array();
			}
			$theme_settings['settings']['color']['custom'] = ! $settings['disableCustomColors'];
		}

		if ( isset( $settings['disableCustomGradients'] ) ) {
			if ( ! isset( $theme_settings['settings']['color'] ) ) {
				$theme_settings['settings']['color'] = array();
			}
			$theme_settings['settings']['color']['customGradient'] = ! $settings['disableCustomGradients'];
		}

		if ( isset( $settings['disableCustomFontSizes'] ) ) {
			if ( ! isset( $theme_settings['settings']['typography'] ) ) {
				$theme_settings['settings']['typography'] = array();
			}
			$theme_settings['settings']['typography']['customFontSize'] = ! $settings['disableCustomFontSizes'];
		}

		if ( isset( $settings['enableCustomLineHeight'] ) ) {
			if ( ! isset( $theme_settings['settings']['typography'] ) ) {
				$theme_settings['settings']['typography'] = array();
			}
			$theme_settings['settings']['typography']['lineHeight'] = $settings['enableCustomLineHeight'];
		}

		if ( isset( $settings['enableCustomUnits'] ) ) {
			if ( ! isset( $theme_settings['settings']['spacing'] ) ) {
				$theme_settings['settings']['spacing'] = array();
			}
			$theme_settings['settings']['spacing']['units'] = ( true === $settings['enableCustomUnits'] ) ?
				array( 'px', 'em', 'rem', 'vh', 'vw', '%' ) :
				$settings['enableCustomUnits'];
		}

		if ( isset( $settings['colors'] ) ) {
			if ( ! isset( $theme_settings['settings']['color'] ) ) {
				$theme_settings['settings']['color'] = array();
			}
			$theme_settings['settings']['color']['palette'] = $settings['colors'];
		}

		if ( isset( $settings['gradients'] ) ) {
			if ( ! isset( $theme_settings['settings']['color'] ) ) {
				$theme_settings['settings']['color'] = array();
			}
			$theme_settings['settings']['color']['gradients'] = $settings['gradients'];
		}

		if ( isset( $settings['fontSizes'] ) ) {
			$font_sizes = $settings['fontSizes'];
			// Back-compatibility for presets without units.
			foreach ( $font_sizes as $key => $font_size ) {
				if ( is_numeric( $font_size['size'] ) ) {
					$font_sizes[ $key ]['size'] = $font_size['size'] . 'px';
				}
			}
			if ( ! isset( $theme_settings['settings']['typography'] ) ) {
				$theme_settings['settings']['typography'] = array();
			}
			$theme_settings['settings']['typography']['fontSizes'] = $font_sizes;
		}

		if ( isset( $settings['enableCustomSpacing'] ) ) {
			if ( ! isset( $theme_settings['settings']['spacing'] ) ) {
				$theme_settings['settings']['spacing'] = array();
			}
			$theme_settings['settings']['spacing']['padding'] = $settings['enableCustomSpacing'];
		}

		return $theme_settings;
	}

	/**
	 * Returns the current theme's wanted patterns(slugs) to be
	 * registered from Pattern Directory.
	 *
	 * @since 6.0.0
	 *
	 * @return string[]
	 */
	public function get_patterns() {
		if ( isset( $this->theme_json['patterns'] ) && is_array( $this->theme_json['patterns'] ) ) {
			return $this->theme_json['patterns'];
		}
		return array();
	}

	/**
	 * Returns a valid theme.json as provided by a theme.
	 *
	 * Unlike get_raw_data() this returns the presets flattened, as provided by a theme.
	 * This also uses appearanceTools instead of their opt-ins if all of them are true.
	 *
	 * @since 6.0.0
	 *
	 * @return array
	 */
	public function get_data() {
		$output = $this->theme_json;
		$nodes  = static::get_setting_nodes( $output );

		/**
		 * Flatten the theme & custom origins into a single one.
		 *
		 * For example, the following:
		 *
		 * {
		 *   "settings": {
		 *     "color": {
		 *       "palette": {
		 *         "theme": [ {} ],
		 *         "custom": [ {} ]
		 *       }
		 *     }
		 *   }
		 * }
		 *
		 * will be converted to:
		 *
		 * {
		 *   "settings": {
		 *     "color": {
		 *       "palette": [ {} ]
		 *     }
		 *   }
		 * }
		 */
		foreach ( $nodes as $node ) {
			foreach ( static::PRESETS_METADATA as $preset_metadata ) {
				$path   = array_merge( $node['path'], $preset_metadata['path'] );
				$preset = _wp_array_get( $output, $path, null );
				if ( null === $preset ) {
					continue;
				}

				$items = array();
				if ( isset( $preset['theme'] ) ) {
					foreach ( $preset['theme'] as $item ) {
						$slug = $item['slug'];
						unset( $item['slug'] );
						$items[ $slug ] = $item;
					}
				}
				if ( isset( $preset['custom'] ) ) {
					foreach ( $preset['custom'] as $item ) {
						$slug = $item['slug'];
						unset( $item['slug'] );
						$items[ $slug ] = $item;
					}
				}
				$flattened_preset = array();
				foreach ( $items as $slug => $value ) {
					$flattened_preset[] = array_merge( array( 'slug' => $slug ), $value );
				}
				_wp_array_set( $output, $path, $flattened_preset );
			}
		}

		// If all of the static::APPEARANCE_TOOLS_OPT_INS are true,
		// this code unsets them and sets 'appearanceTools' instead.
		foreach ( $nodes as $node ) {
			$all_opt_ins_are_set = true;
			foreach ( static::APPEARANCE_TOOLS_OPT_INS as $opt_in_path ) {
				$full_path = array_merge( $node['path'], $opt_in_path );
				// Use "unset prop" as a marker instead of "null" because
				// "null" can be a valid value for some props (e.g. blockGap).
				$opt_in_value = _wp_array_get( $output, $full_path, 'unset prop' );
				if ( 'unset prop' === $opt_in_value ) {
					$all_opt_ins_are_set = false;
					break;
				}
			}

			if ( $all_opt_ins_are_set ) {
				_wp_array_set( $output, array_merge( $node['path'], array( 'appearanceTools' ) ), true );
				foreach ( static::APPEARANCE_TOOLS_OPT_INS as $opt_in_path ) {
					$full_path = array_merge( $node['path'], $opt_in_path );
					// Use "unset prop" as a marker instead of "null" because
					// "null" can be a valid value for some props (e.g. blockGap).
					$opt_in_value = _wp_array_get( $output, $full_path, 'unset prop' );
					if ( true !== $opt_in_value ) {
						continue;
					}

					// The following could be improved to be path independent.
					// At the moment it relies on a couple of assumptions:
					//
					// - all opt-ins having a path of size 2.
					// - there's two sources of settings: the top-level and the block-level.
					if (
						( 1 === count( $node['path'] ) ) &&
						( 'settings' === $node['path'][0] )
					) {
						// Top-level settings.
						unset( $output['settings'][ $opt_in_path[0] ][ $opt_in_path[1] ] );
						if ( empty( $output['settings'][ $opt_in_path[0] ] ) ) {
							unset( $output['settings'][ $opt_in_path[0] ] );
						}
					} elseif (
						( 3 === count( $node['path'] ) ) &&
						( 'settings' === $node['path'][0] ) &&
						( 'blocks' === $node['path'][1] )
					) {
						// Block-level settings.
						$block_name = $node['path'][2];
						unset( $output['settings']['blocks'][ $block_name ][ $opt_in_path[0] ][ $opt_in_path[1] ] );
						if ( empty( $output['settings']['blocks'][ $block_name ][ $opt_in_path[0] ] ) ) {
							unset( $output['settings']['blocks'][ $block_name ][ $opt_in_path[0] ] );
						}
					}
				}
			}
		}

		wp_recursive_ksort( $output );

		return $output;
	}

}