'style' => true,
						'id'    => true,
						'class' => true,
					),
				),
				wp_kses_allowed_html( 'post' )
			)
		);
	}

	/**
	 * Add meta query.
	 *
	 * @since 3.0.0
	 * @param array $args       Query args.
	 * @param array $meta_query Meta query.
	 * @return array
	 */
	protected function add_meta_query( $args, $meta_query ) {
		if ( empty( $args['meta_query'] ) ) {
			$args['meta_query'] = array();
		}

		$args['meta_query'][] = $meta_query;

		return $args['meta_query'];
	}

	/**
	 * Get the batch schema, conforming to JSON Schema.
	 *
	 * @return array
	 */
	public function get_public_batch_schema() {
		$schema = array(
			'$schema'    => 'http://json-schema.org/draft-04/schema#',
			'title'      => 'batch',
			'type'       => 'object',
			'properties' => array(
				'create' => array(
					'description' => __( 'List of created resources.', 'woocommerce' ),
					'type'        => 'array',
					'context'     => array( 'view', 'edit' ),
					'items'       => array(
						'type'    => 'object',
					),
				),
				'update' => array(
					'description' => __( 'List of updated resources.', 'woocommerce' ),
					'type'        => 'array',
					'context'     => array( 'view', 'edit' ),
					'items'       => array(
						'type'    => 'object',
					),
				),
				'delete' => array(
					'description' => __( 'List of delete resources.', 'woocommerce' ),
					'type'        => 'array',
					'context'     => array( 'view', 'edit' ),
					'items'       => array(
						'type'    => 'integer',
					),
				),
			),
		);

		return $schema;
	}

	/**
	 * Gets an array of fields to be included on the response.
	 *
	 * Included fields are based on item schema and `_fields=` request argument.
	 * Updated from WordPress 5.3, included into this class to support old versions.
	 *
	 * @since 3.5.0
	 * @param WP_REST_Request $request Full details about the request.
	 * @return array Fields to be included in the response.
	 */
	public function get_fields_for_response( $request ) {
		// From xdebug profiling, this method could take upto 25% of request time in index calls.
		// Cache it and make sure _fields was cached on current request object!
		// TODO: Submit this caching behavior in core.
		if ( isset( $this->_fields ) && is_array( $this->_fields ) && $request === $this->_request ) {
			return $this->_fields;
		}
		$this->_request = $request;

		$schema     = $this->get_item_schema();
		$properties = isset( $schema['properties'] ) ? $schema['properties'] : array();

		$additional_fields = $this->get_additional_fields();

		foreach ( $additional_fields as $field_name => $field_options ) {
			// For back-compat, include any field with an empty schema
			// because it won't be present in $this->get_item_schema().
			if ( is_null( $field_options['schema'] ) ) {
				$properties[ $field_name ] = $field_options;
			}
		}

		// Exclude fields that specify a different context than the request context.
		$context = $request['context'];
		if ( $context ) {
			foreach ( $properties as $name => $options ) {
				if ( ! empty( $options['context'] ) && ! in_array( $context, $options['context'], true ) ) {
					unset( $properties[ $name ] );
				}
			}
		}

		$fields = array_keys( $properties );

		if ( ! isset( $request['_fields'] ) ) {
			$this->_fields = $fields;
			return $fields;
		}
		$requested_fields = wp_parse_list( $request['_fields'] );
		if ( 0 === count( $requested_fields ) ) {
			$this->_fields = $fields;
			return $fields;
		}
		// Trim off outside whitespace from the comma delimited list.
		$requested_fields = array_map( 'trim', $requested_fields );
		// Always persist 'id', because it can be needed for add_additional_fields_to_object().
		if ( in_array( 'id', $fields, true ) ) {
			$requested_fields[] = 'id';
		}
		// Return the list of all requested fields which appear in the schema.
		$this->_fields = array_reduce(
			$requested_fields,
			function( $response_fields, $field ) use ( $fields ) {
				if ( in_array( $field, $fields, true ) ) {
					$response_fields[] = $field;
					return $response_fields;
				}
				// Check for nested fields if $field is not a direct match.
				$nested_fields = explode( '.', $field );
				// A nested field is included so long as its top-level property
				// is present in the schema.
				if ( in_array( $nested_fields[0], $fields, true ) ) {
					$response_fields[] = $field;
				}
				return $response_fields;
			},
			array()
		);
		return $this->_fields;
	}

	/**
	 * Limit the contents of the meta_data property based on certain request parameters.
	 *
	 * Note that if both `include_meta` and `exclude_meta` are present in the request,
	 * `include_meta` will take precedence.
	 *
	 * @param \WP_REST_Request $request   The request.
	 * @param array            $meta_data All of the meta data for an object.
	 *
	 * @return array
	 */
	protected function get_meta_data_for_response( $request, $meta_data ) {
		$fields = $this->get_fields_for_response( $request );
		if ( ! in_array( 'meta_data', $fields, true ) ) {
			return array();
		}

		$include = (array) $request['include_meta'];
		$exclude = (array) $request['exclude_meta'];

		if ( ! empty( $include ) ) {
			$meta_data = array_filter(
				$meta_data,
				function( WC_Meta_Data $item ) use ( $include ) {
					$data = $item->get_data();
					return in_array( $data['key'], $include, true );
				}
			);
		} elseif ( ! empty( $exclude ) ) {
			$meta_data = array_filter(
				$meta_data,
				function( WC_Meta_Data $item ) use ( $exclude ) {
					$data = $item->get_data();
					return ! in_array( $data['key'], $exclude, true );
				}
			);
		}

		// Ensure the array indexes are reset so it doesn't get converted to an object in JSON.
		return array_values( $meta_data );
	}
}