empty( $allowed_attr ) ) {
		return $css;
	}

	$css = '';
	foreach ( $css_array as $css_item ) {
		if ( '' === $css_item ) {
			continue;
		}

		$css_item        = trim( $css_item );
		$css_test_string = $css_item;
		$found           = false;
		$url_attr        = false;
		$gradient_attr   = false;

		if ( strpos( $css_item, ':' ) === false ) {
			$found = true;
		} else {
			$parts        = explode( ':', $css_item, 2 );
			$css_selector = trim( $parts[0] );

			if ( in_array( $css_selector, $allowed_attr, true ) ) {
				$found         = true;
				$url_attr      = in_array( $css_selector, $css_url_data_types, true );
				$gradient_attr = in_array( $css_selector, $css_gradient_data_types, true );
			}
		}

		if ( $found && $url_attr ) {
			// Simplified: matches the sequence `url(*)`.
			preg_match_all( '/url\([^)]+\)/', $parts[1], $url_matches );

			foreach ( $url_matches[0] as $url_match ) {
				// Clean up the URL from each of the matches above.
				preg_match( '/^url\(\s*([\'\"]?)(.*)(\g1)\s*\)$/', $url_match, $url_pieces );

				if ( empty( $url_pieces[2] ) ) {
					$found = false;
					break;
				}

				$url = trim( $url_pieces[2] );

				if ( empty( $url ) || wp_kses_bad_protocol( $url, $allowed_protocols ) !== $url ) {
					$found = false;
					break;
				} else {
					// Remove the whole `url(*)` bit that was matched above from the CSS.
					$css_test_string = str_replace( $url_match, '', $css_test_string );
				}
			}
		}

		if ( $found && $gradient_attr ) {
			$css_value = trim( $parts[1] );
			if ( preg_match( '/^(repeating-)?(linear|radial|conic)-gradient\(([^()]|rgb[a]?\([^()]*\))*\)$/', $css_value ) ) {
				// Remove the whole `gradient` bit that was matched above from the CSS.
				$css_test_string = str_replace( $css_value, '', $css_test_string );
			}
		}

		if ( $found ) {
			// Allow CSS calc().
			$css_test_string = preg_replace( '/calc\(((?:\([^()]*\)?|[^()])*)\)/', '', $css_test_string );
			// Allow CSS var().
			$css_test_string = preg_replace( '/\(?var\(--[a-zA-Z0-9_-]*\)/', '', $css_test_string );

			// Check for any CSS containing \ ( & } = or comments,
			// except for url(), calc(), or var() usage checked above.
			$allow_css = ! preg_match( '%[\\\(&=}]|/\*%', $css_test_string );

			/**
			 * Filters the check for unsafe CSS in `safecss_filter_attr`.
			 *
			 * Enables developers to determine whether a section of CSS should be allowed or discarded.
			 * By default, the value will be false if the part contains \ ( & } = or comments.
			 * Return true to allow the CSS part to be included in the output.
			 *
			 * @since 5.5.0
			 *
			 * @param bool   $allow_css       Whether the CSS in the test string is considered safe.
			 * @param string $css_test_string The CSS string to test.
			 */
			$allow_css = apply_filters( 'safecss_filter_attr_allow_css', $allow_css, $css_test_string );

			// Only add the CSS part if it passes the regex check.
			if ( $allow_css ) {
				if ( '' !== $css ) {
					$css .= ';';
				}

				$css .= $css_item;
			}
		}
	}

	return $css;
}

/**
 * Helper function to add global attributes to a tag in the allowed HTML list.
 *
 * @since 3.5.0
 * @since 5.0.0 Added support for `data-*` wildcard attributes.
 * @since 6.0.0 Added `dir`, `lang`, and `xml:lang` to global attributes.
 *
 * @access private
 * @ignore
 *
 * @param array $value An array of attributes.
 * @return array The array of attributes with global attributes added.
 */
function _wp_add_global_attributes( $value ) {
	$global_attributes = array(
		'aria-describedby' => true,
		'aria-details'     => true,
		'aria-label'       => true,
		'aria-labelledby'  => true,
		'aria-hidden'      => true,
		'class'            => true,
		'data-*'           => true,
		'dir'              => true,
		'id'               => true,
		'lang'             => true,
		'style'            => true,
		'title'            => true,
		'role'             => true,
		'xml:lang'         => true,
	);

	if ( true === $value ) {
		$value = array();
	}

	if ( is_array( $value ) ) {
		return array_merge( $value, $global_attributes );
	}

	return $value;
}

/**
 * Helper function to check if this is a safe PDF URL.
 *
 * @since 5.9.0
 * @access private
 * @ignore
 *
 * @param string $url The URL to check.
 * @return bool True if the URL is safe, false otherwise.
 */
function _wp_kses_allow_pdf_objects( $url ) {
	// We're not interested in URLs that contain query strings or fragments.
	if ( str_contains( $url, '?' ) || str_contains( $url, '#' ) ) {
		return false;
	}

	// If it doesn't have a PDF extension, it's not safe.
	if ( ! str_ends_with( $url, '.pdf' ) ) {
		return false;
	}

	// If the URL host matches the current site's media URL, it's safe.
	$upload_info = wp_upload_dir( null, false );
	$parsed_url  = wp_parse_url( $upload_info['url'] );
	$upload_host = isset( $parsed_url['host'] ) ? $parsed_url['host'] : '';
	$upload_port = isset( $parsed_url['port'] ) ? ':' . $parsed_url['port'] : '';

	if ( str_starts_with( $url, "http://$upload_host$upload_port/" )
		|| str_starts_with( $url, "https://$upload_host$upload_port/" )
	) {
		return true;
	}

	return false;
}
h Optional. Whether the process should stop after the first successful match.
 * @return array|WP_Error                The matching schema or WP_Error instance if the number of matching schemas is not equal to one.
 */
function rest_find_one_matching_schema( $value, $args, $param, $stop_after_first_match = false ) {
	$matching_schemas = array();
	$errors           = array();

	foreach ( $args['oneOf'] as $index => $schema ) {
		if ( ! isset( $schema['type'] ) && isset( $args['type'] ) ) {
			$schema['type'] = $args['type'];
		}

		$is_valid = rest_validate_value_from_schema( $value, $schema, $param );
		if ( ! is_wp_error( $is_valid ) ) {
			if ( $stop_after_first_match ) {
				return $schema;
			}

			$matching_schemas[] = array(
				'schema_object' => $schema,
				'index'         => $index,
			);
		} else {
			$errors[] = array(
				'error_object' => $is_valid,
				'schema'       => $schema,
				'index'        => $index,
			);
		}
	}

	if ( ! $matching_schemas ) {
		return rest_get_combining_operation_error( $value, $param, $errors );
	}

	if ( count( $matching_schemas ) > 1 ) {
		$schema_positions = array();
		$schema_titles    = array();

		foreach ( $matching_schemas as $schema ) {
			$schema_positions[] = $schema['index'];

			if ( isset( $schema['schema_object']['title'] ) ) {
				$schema_titles[] = $schema['schema_object']['title'];
			}
		}

		// If each schema has a title, include those titles in the error message.
		if ( count( $schema_titles ) === count( $matching_schemas ) ) {
			return new WP_Error(
				'rest_one_of_multiple_matches',
				/* translators: 1: Parameter, 2: Schema titles. */
				wp_sprintf( __( '%1$s matches %2$l, but should match only one.' ), $param, $schema_titles ),
				array( 'positions' => $schema_positions )
			);
		}

		return new WP_Error(
			'rest_one_of_multiple_matches',
			/* translators: %s: Parameter. */
			sprintf( __( '%s matches more than one of the expected formats.' ), $param ),
			array( 'positions' => $schema_positions )
		);
	}

	return $matching_schemas[0]['schema_object'];
}

/**
 * Checks the equality of two values, following JSON Schema semantics.
 *
 * Property order is ignored for objects.
 *
 * Values must have been previously sanitized/coerced to their native types.
 *
 * @since 5.7.0
 *
 * @param mixed $value1 The first value to check.
 * @param mixed $value2 The second value to check.
 * @return bool True if the values are equal or false otherwise.
 */
function rest_are_values_equal( $value1, $value2 ) {
	if ( is_array( $value1 ) && is_array( $value2 ) ) {
		if ( count( $value1 ) !== count( $value2 ) ) {
			return false;
		}

		foreach ( $value1 as $index => $value ) {
			if ( ! array_key_exists( $index, $value2 ) || ! rest_are_values_equal( $value, $value2[ $index ] ) ) {
				return false;
			}
		}

		return true;
	}

	if ( is_int( $value1 ) && is_float( $value2 )
		|| is_float( $value1 ) && is_int( $value2 )
	) {
		return (float) $value1 === (float) $value2;
	}

	return $value1 === $value2;
}

/**
 * Validates that the given value is a member of the JSON Schema "enum".
 *
 * @since 5.7.0
 *
 * @param mixed  $value  The value to validate.
 * @param array  $args   The schema array to use.
 * @param string $param  The parameter name, used in error messages.
 * @return true|WP_Error True if the "enum" contains the value or a WP_Error instance otherwise.
 */
function rest_validate_enum( $value, $args, $param ) {
	$sanitized_value = rest_sanitize_value_from_schema( $value, $args, $param );
	if ( is_wp_error( $sanitized_value ) ) {
		return $sanitized_value;
	}

	foreach ( $args['enum'] as $enum_value ) {
		if ( rest_are_values_equal( $sanitized_value, $enum_value ) ) {
			return true;
		}
	}

	$encoded_enum_values = array();
	foreach ( $args['enum'] as $enum_value ) {
		$encoded_enum_values[] = is_scalar( $enum_value ) ? $enum_value : wp_json_encode( $enum_value );
	}

	if ( count( $encoded_enum_values ) === 1 ) {
		/* translators: 1: Parameter, 2: Valid values. */
		return new WP_Error( 'rest_not_in_enum', wp_sprintf( __( '%1$s is not %2$s.' ), $param, $encoded_enum_values[0] ) );
	}

	/* translators: 1: Parameter, 2: List of valid values. */
	return new WP_Error( 'rest_not_in_enum', wp_sprintf( __( '%1$s is not one of %2$l.' ), $param, $encoded_enum_values ) );
}

/**
 * Get all valid JSON schema properties.
 *
 * @since 5.6.0
 *
 * @return string[] All valid JSON schema properties.
 */
function rest_get_allowed_schema_keywords() {
	return array(
		'title',
		'description',
		'default',
		'type',
		'format',
		'enum',
		'items',
		'properties',
		'additionalProperties',
		'patternProperties',
		'minProperties',
		'maxProperties',
		'minimum',
		'maximum',
		'exclusiveMinimum',
		'exclusiveMaximum',
		'multipleOf',
		'minLength',
		'maxLength',
		'pattern',
		'minItems',
		'maxItems',
		'uniqueItems',
		'anyOf',
		'oneOf',
	);
}

/**
 * Validate a value based on a schema.
 *
 * @since 4.7.0
 * @since 4.9.0 Support the "object" type.
 * @since 5.2.0 Support validating "additionalProperties" against a schema.
 * @since 5.3.0 Support multiple types.
 * @since 5.4.0 Convert an empty string to an empty object.
 * @since 5.5.0 Add the "uuid" and "hex-color" formats.
 *              Support the "minLength", "maxLength" and "pattern" keywords for strings.
 *              Support the "minItems", "maxItems" and "uniqueItems" keywords for arrays.
 *              Validate required properties.
 * @since 5.6.0 Support the "minProperties" and "maxProperties" keywords for objects.
 *              Support the "multipleOf" keyword for numbers and integers.
 *              Support the "patternProperties" keyword for objects.
 *              Support the "anyOf" and "oneOf" keywords.
 *
 * @param mixed  $value The value to validate.
 * @param array  $args  Schema array to use for validation.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_value_from_schema( $value, $args, $param = '' ) {
	if ( isset( $args['anyOf'] ) ) {
		$matching_schema = rest_find_any_matching_schema( $value, $args, $param );
		if ( is_wp_error( $matching_schema ) ) {
			return $matching_schema;
		}

		if ( ! isset( $args['type'] ) && isset( $matching_schema['type'] ) ) {
			$args['type'] = $matching_schema['type'];
		}
	}

	if ( isset( $args['oneOf'] ) ) {
		$matching_schema = rest_find_one_matching_schema( $value, $args, $param );
		if ( is_wp_error( $matching_schema ) ) {
			return $matching_schema;
		}

		if ( ! isset( $args['type'] ) && isset( $matching_schema['type'] ) ) {
			$args['type'] = $matching_schema['type'];
		}
	}

	$allowed_types = array( 'array', 'object', 'string', 'number', 'integer', 'boolean', 'null' );

	if ( ! isset( $args['type'] ) ) {
		/* translators: %s: Parameter. */
		_doing_it_wrong( __FUNCTION__, sprintf( __( 'The "type" schema keyword for %s is required.' ), $param ), '5.5.0' );
	}

	if ( is_array( $args['type'] ) ) {
		$best_type = rest_handle_multi_type_schema( $value, $args, $param );

		if ( ! $best_type ) {
			return new WP_Error(
				'rest_invalid_type',
				/* translators: 1: Parameter, 2: List of types. */
				sprintf( __( '%1$s is not of type %2$s.' ), $param, implode( ',', $args['type'] ) ),
				array( 'param' => $param )
			);
		}

		$args['type'] = $best_type;
	}

	if ( ! in_array( $args['type'], $allowed_types, true ) ) {
		_doing_it_wrong(
			__FUNCTION__,
			/* translators: 1: Parameter, 2: The list of allowed types. */
			wp_sprintf( __( 'The "type" schema keyword for %1$s can only be one of the built-in types: %2$l.' ), $param, $allowed_types ),
			'5.5.0'
		);
	}

	switch ( $args['type'] ) {
		case 'null':
			$is_valid = rest_validate_null_value_from_schema( $value, $param );
			break;
		case 'boolean':
			$is_valid = rest_validate_boolean_value_from_schema( $value, $param );
			break;
		case 'object':
			$is_valid = rest_validate_object_value_from_schema( $value, $args, $param );
			break;
		case 'array':
			$is_valid = rest_validate_array_value_from_schema( $value, $args, $param );
			break;
		case 'number':
			$is_valid = rest_validate_number_value_from_schema( $value, $args, $param );
			break;
		case 'string':
			$is_valid = rest_validate_string_value_from_schema( $value, $args, $param );
			break;
		case 'integer':
			$is_valid = rest_validate_integer_value_from_schema( $value, $args, $param );
			break;
		default:
			$is_valid = true;
			break;
	}

	if ( is_wp_error( $is_valid ) ) {
		return $is_valid;
	}

	if ( ! empty( $args['enum'] ) ) {
		$enum_contains_value = rest_validate_enum( $value, $args, $param );
		if ( is_wp_error( $enum_contains_value ) ) {
			return $enum_contains_value;
		}
	}

	// The "format" keyword should only be applied to strings. However, for backward compatibility,
	// we allow the "format" keyword if the type keyword was not specified, or was set to an invalid value.
	if ( isset( $args['format'] )
		&& ( ! isset( $args['type'] ) || 'string' === $args['type'] || ! in_array( $args['type'], $allowed_types, true ) )
	) {
		switch ( $args['format'] ) {
			case 'hex-color':
				if ( ! rest_parse_hex_color( $value ) ) {
					return new WP_Error( 'rest_invalid_hex_color', __( 'Invalid hex color.' ) );
				}
				break;

			case 'date-time':
				if ( ! rest_parse_date( $value ) ) {
					return new WP_Error( 'rest_invalid_date', __( 'Invalid date.' ) );
				}
				break;

			case 'email':
				if ( ! is_email( $value ) ) {
					return new WP_Error( 'rest_invalid_email', __( 'Invalid email address.' ) );
				}
				break;
			case 'ip':
				if ( ! rest_is_ip_address( $value ) ) {
					/* translators: %s: IP address. */
					return new WP_Error( 'rest_invalid_ip', sprintf( __( '%s is not a valid IP address.' ), $param ) );
				}
				break;
			case 'uuid':
				if ( ! wp_is_uuid( $value ) ) {
					/* translators: %s: The name of a JSON field expecting a valid UUID. */
					return new WP_Error( 'rest_invalid_uuid', sprintf( __( '%s is not a valid UUID.' ), $param ) );
				}
				break;
		}
	}

	return true;
}

/**
 * Validates a null value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_null_value_from_schema( $value, $param ) {
	if ( null !== $value ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, 'null' ),
			array( 'param' => $param )
		);
	}

	return true;
}

/**
 * Validates a boolean value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_boolean_value_from_schema( $value, $param ) {
	if ( ! rest_is_boolean( $value ) ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, 'boolean' ),
			array( 'param' => $param )
		);
	}

	return true;
}

/**
 * Validates an object value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param array  $args  Schema array to use for validation.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_object_value_from_schema( $value, $args, $param ) {
	if ( ! rest_is_object( $value ) ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, 'object' ),
			array( 'param' => $param )
		);
	}

	$value = rest_sanitize_object( $value );

	if ( isset( $args['required'] ) && is_array( $args['required'] ) ) { // schema version 4
		foreach ( $args['required'] as $name ) {
			if ( ! array_key_exists( $name, $value ) ) {
				return new WP_Error(
					'rest_property_required',
					/* translators: 1: Property of an object, 2: Parameter. */
					sprintf( __( '%1$s is a required property of %2$s.' ), $name, $param )
				);
			}
		}
	} elseif ( isset( $args['properties'] ) ) { // schema version 3
		foreach ( $args['properties'] as $name => $property ) {
			if ( isset( $property['required'] ) && true === $property['required'] && ! array_key_exists( $name, $value ) ) {
				return new WP_Error(
					'rest_property_required',
					/* translators: 1: Property of an object, 2: Parameter. */
					sprintf( __( '%1$s is a required property of %2$s.' ), $name, $param )
				);
			}
		}
	}

	foreach ( $value as $property => $v ) {
		if ( isset( $args['properties'][ $property ] ) ) {
			$is_valid = rest_validate_value_from_schema( $v, $args['properties'][ $property ], $param . '[' . $property . ']' );
			if ( is_wp_error( $is_valid ) ) {
				return $is_valid;
			}
			continue;
		}

		$pattern_property_schema = rest_find_matching_pattern_property_schema( $property, $args );
		if ( null !== $pattern_property_schema ) {
			$is_valid = rest_validate_value_from_schema( $v, $pattern_property_schema, $param . '[' . $property . ']' );
			if ( is_wp_error( $is_valid ) ) {
				return $is_valid;
			}
			continue;
		}

		if ( isset( $args['additionalProperties'] ) ) {
			if ( false === $args['additionalProperties'] ) {
				return new WP_Error(
					'rest_additional_properties_forbidden',
					/* translators: %s: Property of an object. */
					sprintf( __( '%1$s is not a valid property of Object.' ), $property )
				);
			}

			if ( is_array( $args['additionalProperties'] ) ) {
				$is_valid = rest_validate_value_from_schema( $v, $args['additionalProperties'], $param . '[' . $property . ']' );
				if ( is_wp_error( $is_valid ) ) {
					return $is_valid;
				}
			}
		}
	}

	if ( isset( $args['minProperties'] ) && count( $value ) < $args['minProperties'] ) {
		return new WP_Error(
			'rest_too_few_properties',
			sprintf(
				/* translators: 1: Parameter, 2: Number. */
				_n(
					'%1$s must contain at least %2$s property.',
					'%1$s must contain at least %2$s properties.',
					$args['minProperties']
				),
				$param,
				number_format_i18n( $args['minProperties'] )
			)
		);
	}

	if ( isset( $args['maxProperties'] ) && count( $value ) > $args['maxProperties'] ) {
		return new WP_Error(
			'rest_too_many_properties',
			sprintf(
				/* translators: 1: Parameter, 2: Number. */
				_n(
					'%1$s must contain at most %2$s property.',
					'%1$s must contain at most %2$s properties.',
					$args['maxProperties']
				),
				$param,
				number_format_i18n( $args['maxProperties'] )
			)
		);
	}

	return true;
}

/**
 * Validates an array value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param array  $args  Schema array to use for validation.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_array_value_from_schema( $value, $args, $param ) {
	if ( ! rest_is_array( $value ) ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, 'array' ),
			array( 'param' => $param )
		);
	}

	$value = rest_sanitize_array( $value );

	if ( isset( $args['items'] ) ) {
		foreach ( $value as $index => $v ) {
			$is_valid = rest_validate_value_from_schema( $v, $args['items'], $param . '[' . $index . ']' );
			if ( is_wp_error( $is_valid ) ) {
				return $is_valid;
			}
		}
	}

	if ( isset( $args['minItems'] ) && count( $value ) < $args['minItems'] ) {
		return new WP_Error(
			'rest_too_few_items',
			sprintf(
				/* translators: 1: Parameter, 2: Number. */
				_n(
					'%1$s must contain at least %2$s item.',
					'%1$s must contain at least %2$s items.',
					$args['minItems']
				),
				$param,
				number_format_i18n( $args['minItems'] )
			)
		);
	}

	if ( isset( $args['maxItems'] ) && count( $value ) > $args['maxItems'] ) {
		return new WP_Error(
			'rest_too_many_items',
			sprintf(
				/* translators: 1: Parameter, 2: Number. */
				_n(
					'%1$s must contain at most %2$s item.',
					'%1$s must contain at most %2$s items.',
					$args['maxItems']
				),
				$param,
				number_format_i18n( $args['maxItems'] )
			)
		);
	}

	if ( ! empty( $args['uniqueItems'] ) && ! rest_validate_array_contains_unique_items( $value ) ) {
		/* translators: %s: Parameter. */
		return new WP_Error( 'rest_duplicate_items', sprintf( __( '%s has duplicate items.' ), $param ) );
	}

	return true;
}

/**
 * Validates a number value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param array  $args  Schema array to use for validation.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_number_value_from_schema( $value, $args, $param ) {
	if ( ! is_numeric( $value ) ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, $args['type'] ),
			array( 'param' => $param )
		);
	}

	if ( isset( $args['multipleOf'] ) && fmod( $value, $args['multipleOf'] ) !== 0.0 ) {
		return new WP_Error(
			'rest_invalid_multiple',
			/* translators: 1: Parameter, 2: Multiplier. */
			sprintf( __( '%1$s must be a multiple of %2$s.' ), $param, $args['multipleOf'] )
		);
	}

	if ( isset( $args['minimum'] ) && ! isset( $args['maximum'] ) ) {
		if ( ! empty( $args['exclusiveMinimum'] ) && $value <= $args['minimum'] ) {
			return new WP_Error(
				'rest_out_of_bounds',
				/* translators: 1: Parameter, 2: Minimum number. */
				sprintf( __( '%1$s must be greater than %2$d' ), $param, $args['minimum'] )
			);
		}

		if ( empty( $args['exclusiveMinimum'] ) && $value < $args['minimum'] ) {
			return new WP_Error(
				'rest_out_of_bounds',
				/* translators: 1: Parameter, 2: Minimum number. */
				sprintf( __( '%1$s must be greater than or equal to %2$d' ), $param, $args['minimum'] )
			);
		}
	}

	if ( isset( $args['maximum'] ) && ! isset( $args['minimum'] ) ) {
		if ( ! empty( $args['exclusiveMaximum'] ) && $value >= $args['maximum'] ) {
			return new WP_Error(
				'rest_out_of_bounds',
				/* translators: 1: Parameter, 2: Maximum number. */
				sprintf( __( '%1$s must be less than %2$d' ), $param, $args['maximum'] )
			);
		}

		if ( empty( $args['exclusiveMaximum'] ) && $value > $args['maximum'] ) {
			return new WP_Error(
				'rest_out_of_bounds',
				/* translators: 1: Parameter, 2: Maximum number. */
				sprintf( __( '%1$s must be less than or equal to %2$d' ), $param, $args['maximum'] )
			);
		}
	}

	if ( isset( $args['minimum'], $args['maximum'] ) ) {
		if ( ! empty( $args['exclusiveMinimum'] ) && ! empty( $args['exclusiveMaximum'] ) ) {
			if ( $value >= $args['maximum'] || $value <= $args['minimum'] ) {
				return new WP_Error(
					'rest_out_of_bounds',
					sprintf(
						/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
						__( '%1$s must be between %2$d (exclusive) and %3$d (exclusive)' ),
						$param,
						$args['minimum'],
						$args['maximum']
					)
				);
			}
		}

		if ( ! empty( $args['exclusiveMinimum'] ) && empty( $args['exclusiveMaximum'] ) ) {
			if ( $value > $args['maximum'] || $value <= $args['minimum'] ) {
				return new WP_Error(
					'rest_out_of_bounds',
					sprintf(
						/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
						__( '%1$s must be between %2$d (exclusive) and %3$d (inclusive)' ),
						$param,
						$args['minimum'],
						$args['maximum']
					)
				);
			}
		}

		if ( ! empty( $args['exclusiveMaximum'] ) && empty( $args['exclusiveMinimum'] ) ) {
			if ( $value >= $args['maximum'] || $value < $args['minimum'] ) {
				return new WP_Error(
					'rest_out_of_bounds',
					sprintf(
						/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
						__( '%1$s must be between %2$d (inclusive) and %3$d (exclusive)' ),
						$param,
						$args['minimum'],
						$args['maximum']
					)
				);
			}
		}

		if ( empty( $args['exclusiveMinimum'] ) && empty( $args['exclusiveMaximum'] ) ) {
			if ( $value > $args['maximum'] || $value < $args['minimum'] ) {
				return new WP_Error(
					'rest_out_of_bounds',
					sprintf(
						/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
						__( '%1$s must be between %2$d (inclusive) and %3$d (inclusive)' ),
						$param,
						$args['minimum'],
						$args['maximum']
					)
				);
			}
		}
	}

	return true;
}

/**
 * Validates a string value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param array  $args  Schema array to use for validation.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_string_value_from_schema( $value, $args, $param ) {
	if ( ! is_string( $value ) ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, 'string' ),
			array( 'param' => $param )
		);
	}

	if ( isset( $args['minLength'] ) && mb_strlen( $value ) < $args['minLength'] ) {
		return new WP_Error(
			'rest_too_short',
			sprintf(
				/* translators: 1: Parameter, 2: Number of characters. */
				_n(
					'%1$s must be at least %2$s character long.',
					'%1$s must be at least %2$s characters long.',
					$args['minLength']
				),
				$param,
				number_format_i18n( $args['minLength'] )
			)
		);
	}

	if ( isset( $args['maxLength'] ) && mb_strlen( $value ) > $args['maxLength'] ) {
		return new WP_Error(
			'rest_too_long',
			sprintf(
				/* translators: 1: Parameter, 2: Number of characters. */
				_n(
					'%1$s must be at most %2$s character long.',
					'%1$s must be at most %2$s characters long.',
					$args['maxLength']
				),
				$param,
				number_format_i18n( $args['maxLength'] )
			)
		);
	}

	if ( isset( $args['pattern'] ) && ! rest_validate_json_schema_pattern( $args['pattern'], $value ) ) {
		return new WP_Error(
			'rest_invalid_pattern',
			/* translators: 1: Parameter, 2: Pattern. */
			sprintf( __( '%1$s does not match pattern %2$s.' ), $param, $args['pattern'] )
		);
	}

	return true;
}

/**
 * Validates an integer value based on a schema.
 *
 * @since 5.7.0
 *
 * @param mixed  $value The value to validate.
 * @param array  $args  Schema array to use for validation.
 * @param string $param The parameter name, used in error messages.
 * @return true|WP_Error
 */
function rest_validate_integer_value_from_schema( $value, $args, $param ) {
	$is_valid_number = rest_validate_number_value_from_schema( $value, $args, $param );
	if ( is_wp_error( $is_valid_number ) ) {
		return $is_valid_number;
	}

	if ( ! rest_is_integer( $value ) ) {
		return new WP_Error(
			'rest_invalid_type',
			/* translators: 1: Parameter, 2: Type name. */
			sprintf( __( '%1$s is not of type %2$s.' ), $param, 'integer' ),
			array( 'param' => $param )
		);
	}

	return true;
}

/**
 * Sanitize a value based on a schema.
 *
 * @since 4.7.0
 * @since 5.5.0 Added the `$param` parameter.
 * @since 5.6.0 Support the "anyOf" and "oneOf" keywords.
 * @since 5.9.0 Added `text-field` and `textarea-field` formats.
 *
 * @param mixed  $value The value to sanitize.
 * @param array  $args  Schema array to use for sanitization.
 * @param string $param The parameter name, used in error messages.
 * @return mixed|WP_Error The sanitized value or a WP_Error instance if the value cannot be safely sanitized.
 */
function rest_sanitize_value_from_schema( $value, $args, $param = '' ) {
	if ( isset( $args['anyOf'] ) ) {
		$matching_schema = rest_find_any_matching_schema( $value, $args, $param );
		if ( is_wp_error( $matching_schema ) ) {
			return $matching_schema;
		}

		if ( ! isset( $args['type'] ) ) {
			$args['type'] = $matching_schema['type'];
		}

		$value = rest_sanitize_value_from_schema( $value, $matching_schema, $param );
	}

	if ( isset( $args['oneOf'] ) ) {
		$matching_schema = rest_find_one_matching_schema( $value, $args, $param );
		if ( is_wp_error( $matching_schema ) ) {
			return $matching_schema;
		}

		if ( ! isset( $args['type'] ) ) {
			$args['type'] = $matching_schema['type'];
		}

		$value = rest_sanitize_value_from_schema( $value, $matching_schema, $param );
	}

	$allowed_types = array( 'array', 'object', 'string', 'number', 'integer', 'boolean', 'null' );

	if ( ! isset( $args['type'] ) ) {
		/* translators: %s: Parameter. */
		_doing_it_wrong( __FUNCTION__, sprintf( __( 'The "type" schema keyword for %s is required.' ), $param ), '5.5.0' );
	}

	if ( is_array( $args['type'] ) ) {
		$best_type = rest_handle_multi_type_schema( $value, $args, $param );

		if ( ! $best_type ) {
			return null;
		}

		$args['type'] = $best_type;
	}

	if ( ! in_array( $args['type'], $allowed_types, true ) ) {
		_doing_it_wrong(
			__FUNCTION__,
			/* translators: 1: Parameter, 2: The list of allowed types. */
			wp_sprintf( __( 'The "type" schema keyword for %1$s can only be one of the built-in types: %2$l.' ), $param, $allowed_types ),
			'5.5.0'
		);
	}

	if ( 'array' === $args['type'] ) {
		$value = rest_sanitize_array( $value );

		if ( ! empty( $args['items'] ) ) {
			foreach ( $value as $index => $v ) {
				$value[ $index ] = rest_sanitize_value_from_schema( $v, $args['items'], $param . '[' . $index . ']' );
			}
		}

		if ( ! empty( $args['uniqueItems'] ) && ! rest_validate_array_contains_unique_items( $value ) ) {
			/* translators: %s: Parameter. */
			return new WP_Error( 'rest_duplicate_items', sprintf( __( '%s has duplicate items.' ), $param ) );
		}

		return $value;
	}

	if ( 'object' === $args['type'] ) {
		$value = rest_sanitize_object( $value );

		foreach ( $value as $property => $v ) {
			if ( isset( $args['properties'][ $property ] ) ) {
				$value[ $property ] = rest_sanitize_value_from_schema( $v, $args['properties'][ $property ], $param . '[' . $property . ']' );
				continue;
			}

			$pattern_property_schema = rest_find_matching_pattern_property_schema( $property, $args );
			if ( null !== $pattern_property_schema ) {
				$value[ $property ] = rest_sanitize_value_from_schema( $v, $pattern_property_schema, $param . '[' . $property . ']' );
				continue;
			}

			if ( isset( $args['additionalProperties'] ) ) {
				if ( false === $args['additionalProperties'] ) {
					unset( $value[ $property ] );
				} elseif ( is_array( $args['additionalProperties'] ) ) {
					$value[ $property ] = rest_sanitize_value_from_schema( $v, $args['additionalProperties'], $param . '[' . $property . ']' );
				}
			}
		}

		return $value;
	}

	if ( 'null' === $args['type'] ) {
		return null;
	}

	if ( 'integer' === $args['type'] ) {
		return (int) $value;
	}

	if ( 'number' === $args['type'] ) {
		return (float) $value;
	}

	if ( 'boolean' === $args['type'] ) {
		return rest_sanitize_boolean( $value );
	}

	// This behavior matches rest_validate_value_from_schema().
	if ( isset( $args['format'] )
		&& ( ! isset( $args['type'] ) || 'string' === $args['type'] || ! in_array( $args['type'], $allowed_types, true ) )
	) {
		switch ( $args['format'] ) {
			case 'hex-color':
				return (string) sanitize_hex_color( $value );

			case 'date-time':
				return sanitize_text_field( $value );

			case 'email':
				// sanitize_email() validates, which would be unexpected.
				return sanitize_text_field( $value );

			case 'uri':
				return esc_url_raw( $value );

			case 'ip':
				return sanitize_text_field( $value );

			case 'uuid':
				return sanitize_text_field( $value );

			case 'text-field':
				return sanitize_text_field( $value );

			case 'textarea-field':
				return sanitize_textarea_field( $value );
		}
	}

	if ( 'string' === $args['type'] ) {
		return (string) $value;
	}

	return $value;
}

/**
 * Append result of internal request to REST API for purpose of preloading data to be attached to a page.
 * Expected to be called in the context of `array_reduce`.
 *
 * @since 5.0.0
 *
 * @param array  $memo Reduce accumulator.
 * @param string $path REST API path to preload.
 * @return array Modified reduce accumulator.
 */
function rest_preload_api_request( $memo, $path ) {
	// array_reduce() doesn't support passing an array in PHP 5.2,
	// so we need to make sure we start with one.
	if ( ! is_array( $memo ) ) {
		$memo = array();
	}

	if ( empty( $path ) ) {
		return $memo;
	}

	$method = 'GET';
	if ( is_array( $path ) && 2 === count( $path ) ) {
		$method = end( $path );
		$path   = reset( $path );

		if ( ! in_array( $method, array( 'GET', 'OPTIONS' ), true ) ) {
			$method = 'GET';
		}
	}

	$path = untrailingslashit( $path );
	if ( empty( $path ) ) {
		$path = '/';
	}

	$path_parts = parse_url( $path );
	if ( false === $path_parts ) {
		return $memo;
	}

	$request = new WP_REST_Request( $method, $path_parts['path'] );
	if ( ! empty( $path_parts['query'] ) ) {
		parse_str( $path_parts['query'], $query_params );
		$request->set_query_params( $query_params );
	}

	$response = rest_do_request( $request );
	if ( 200 === $response->status ) {
		$server = rest_get_server();
		/** This filter is documented in wp-includes/rest-api/class-wp-rest-server.php */
		$response = apply_filters( 'rest_post_dispatch', rest_ensure_response( $response ), $server, $request );
		$embed  = $request->has_param( '_embed' ) ? rest_parse_embed_param( $request['_embed'] ) : false;
		$data   = (array) $server->response_to_data( $response, $embed );

		if ( 'OPTIONS' === $method ) {
			$memo[ $method ][ $path ] = array(
				'body'    => $data,
				'headers' => $response->headers,
			);
		} else {
			$memo[ $path ] = array(
				'body'    => $data,
				'headers' => $response->headers,
			);
		}
	}

	return $memo;
}

/**
 * Parses the "_embed" parameter into the list of resources to embed.
 *
 * @since 5.4.0
 *
 * @param string|array $embed Raw "_embed" parameter value.
 * @return true|string[] Either true to embed all embeds, or a list of relations to embed.
 */
function rest_parse_embed_param( $embed ) {
	if ( ! $embed || 'true' === $embed || '1' === $embed ) {
		return true;
	}

	$rels = wp_parse_list( $embed );

	if ( ! $rels ) {
		return true;
	}

	return $rels;
}

/**
 * Filters the response to remove any fields not available in the given context.
 *
 * @since 5.5.0
 * @since 5.6.0 Support the "patternProperties" keyword for objects.
 *              Support the "anyOf" and "oneOf" keywords.
 *
 * @param array|object $data    The response data to modify.
 * @param array        $schema  The schema for the endpoint used to filter the response.
 * @param string       $context The requested context.
 * @return array|object The filtered response data.
 */
function rest_filter_response_by_context( $data, $schema, $context ) {
	if ( isset( $schema['anyOf'] ) ) {
		$matching_schema = rest_find_any_matching_schema( $data, $schema, '' );
		if ( ! is_wp_error( $matching_schema ) ) {
			if ( ! isset( $schema['type'] ) ) {
				$schema['type'] = $matching_schema['type'];
			}

			$data = rest_filter_response_by_context( $data, $matching_schema, $context );
		}
	}

	if ( isset( $schema['oneOf'] ) ) {
		$matching_schema = rest_find_one_matching_schema( $data, $schema, '', true );
		if ( ! is_wp_error( $matching_schema ) ) {
			if ( ! isset( $schema['type'] ) ) {
				$schema['type'] = $matching_schema['type'];
			}

			$data = rest_filter_response_by_context( $data, $matching_schema, $context );
		}
	}

	if ( ! is_array( $data ) && ! is_object( $data ) ) {
		return $data;
	}

	if ( isset( $schema['type'] ) ) {
		$type = $schema['type'];
	} elseif ( isset( $schema['properties'] ) ) {
		$type = 'object'; // Back compat if a developer accidentally omitted the type.
	} else {
		return $data;
	}

	$is_array_type  = 'array' === $type || ( is_array( $type ) && in_array( 'array', $type, true ) );
	$is_object_type = 'object' === $type || ( is_array( $type ) && in_array( 'object', $type, true ) );

	if ( $is_array_type && $is_object_type ) {
		if ( rest_is_array( $data ) ) {
			$is_object_type = false;
		} else {
			$is_array_type = false;
		}
	}

	$has_additional_properties = $is_object_type && isset( $schema['additionalProperties'] ) && is_array( $schema['additionalProperties'] );

	foreach ( $data as $key => $value ) {
		$check = array();

		if ( $is_array_type ) {
			$check = isset( $schema['items'] ) ? $schema['items'] : array();
		} elseif ( $is_object_type ) {
			if ( isset( $schema['properties'][ $key ] ) ) {
				$check = $schema['properties'][ $key ];
			} else {
				$pattern_property_schema = rest_find_matching_pattern_property_schema( $key, $schema );
				if ( null !== $pattern_property_schema ) {
					$check = $pattern_property_schema;
				} elseif ( $has_additional_properties ) {
					$check = $schema['additionalProperties'];
				}
			}
		}

		if ( ! isset( $check['context'] ) ) {
			continue;
		}

		if ( ! in_array( $context, $check['context'], true ) ) {
			if ( $is_array_type ) {
				// All array items share schema, so there's no need to check each one.
				$data = array();
				break;
			}

			if ( is_object( $data ) ) {
				unset( $data->$key );
			} else {
				unset( $data[ $key ] );
			}
		} elseif ( is_array( $value ) || is_object( $value ) ) {
			$new_value = rest_filter_response_by_context( $value, $check, $context );

			if ( is_object( $data ) ) {
				$data->$key = $new_value;
			} else {
				$data[ $key ] = $new_value;
			}
		}
	}

	return $data;
}

/**
 * Sets the "additionalProperties" to false by default for all object definitions in the schema.
 *
 * @since 5.5.0
 * @since 5.6.0 Support the "patternProperties" keyword.
 *
 * @param array $schema The schema to modify.
 * @return array The modified schema.
 */
function rest_default_additional_properties_to_false( $schema ) {
	$type = (array) $schema['type'];

	if ( in_array( 'object', $type, true ) ) {
		if ( isset( $schema['properties'] ) ) {
			foreach ( $schema['properties'] as $key => $child_schema ) {
				$schema['properties'][ $key ] = rest_default_additional_properties_to_false( $child_schema );
			}
		}

		if ( isset( $schema['patternProperties'] ) ) {
			foreach ( $schema['patternProperties'] as $key => $child_schema ) {
				$schema['patternProperties'][ $key ] = rest_default_additional_properties_to_false( $child_schema );
			}
		}

		if ( ! isset( $schema['additionalProperties'] ) ) {
			$schema['additionalProperties'] = false;
		}
	}

	if ( in_array( 'array', $type, true ) ) {
		if ( isset( $schema['items'] ) ) {
			$schema['items'] = rest_default_additional_properties_to_false( $schema['items'] );
		}
	}

	return $schema;
}

/**
 * Gets the REST API route for a post.
 *
 * @since 5.5.0
 *
 * @param int|WP_Post $post Post ID or post object.
 * @return string The route path with a leading slash for the given post,
 *                or an empty string if there is not a route.
 */
function rest_get_route_for_post( $post ) {
	$post = get_post( $post );

	if ( ! $post instanceof WP_Post ) {
		return '';
	}

	$post_type_route = rest_get_route_for_post_type_items( $post->post_type );
	if ( ! $post_type_route ) {
		return '';
	}

	$route = sprintf( '%s/%d', $post_type_route, $post->ID );

	/**
	 * Filters the REST API route for a post.
	 *
	 * @since 5.5.0
	 *
	 * @param string  $route The route path.
	 * @param WP_Post $post  The post object.
	 */
	return apply_filters( 'rest_route_for_post', $route, $post );
}

/**
 * Gets the REST API route for a post type.
 *
 * @since 5.9.0
 *
 * @param string $post_type The name of a registered post type.
 * @return string The route path with a leading slash for the given post type,
 *                or an empty string if there is not a route.
 */
function rest_get_route_for_post_type_items( $post_type ) {
	$post_type = get_post_type_object( $post_type );
	if ( ! $post_type ) {
		return '';
	}

	if ( ! $post_type->show_in_rest ) {
		return '';
	}

	$namespace = ! empty( $post_type->rest_namespace ) ? $post_type->rest_namespace : 'wp/v2';
	$rest_base = ! empty( $post_type->rest_base ) ? $post_type->rest_base : $post_type->name;
	$route     = sprintf( '/%s/%s', $namespace, $rest_base );

	/**
	 * Filters the REST API route for a post type.
	 *
	 * @since 5.9.0
	 *
	 * @param string       $route      The route path.
	 * @param WP_Post_Type $post_type  The post type object.
	 */
	return apply_filters( 'rest_route_for_post_type_items', $route, $post_type );
}

/**
 * Gets the REST API route for a term.
 *
 * @since 5.5.0
 *
 * @param int|WP_Term $term Term ID or term object.
 * @return string The route path with a leading slash for the given term,
 *                or an empty string if there is not a route.
 */
function rest_get_route_for_term( $term ) {
	$term = get_term( $term );

	if ( ! $term instanceof WP_Term ) {
		return '';
	}

	$taxonomy_route = rest_get_route_for_taxonomy_items( $term->taxonomy );
	if ( ! $taxonomy_route ) {
		return '';
	}

	$route = sprintf( '%s/%d', $taxonomy_route, $term->term_id );

	/**
	 * Filters the REST API route for a term.
	 *
	 * @since 5.5.0
	 *
	 * @param string  $route The route path.
	 * @param WP_Term $term  The term object.
	 */
	return apply_filters( 'rest_route_for_term', $route, $term );
}

/**
 * Gets the REST API route for a taxonomy.
 *
 * @since 5.9.0
 *
 * @param string $taxonomy Name of taxonomy.
 * @return string The route path with a leading slash for the given taxonomy.
 */
function rest_get_route_for_taxonomy_items( $taxonomy ) {
	$taxonomy = get_taxonomy( $taxonomy );
	if ( ! $taxonomy ) {
		return '';
	}

	if ( ! $taxonomy->show_in_rest ) {
		return '';
	}

	$namespace = ! empty( $taxonomy->rest_namespace ) ? $taxonomy->rest_namespace : 'wp/v2';
	$rest_base = ! empty( $taxonomy->rest_base ) ? $taxonomy->rest_base : $taxonomy->name;
	$route     = sprintf( '/%s/%s', $namespace, $rest_base );

	/**
	 * Filters the REST API route for a taxonomy.
	 *
	 * @since 5.9.0
	 *
	 * @param string      $route    The route path.
	 * @param WP_Taxonomy $taxonomy The taxonomy object.
	 */
	return apply_filters( 'rest_route_for_taxonomy_items', $route, $taxonomy );
}

/**
 * Gets the REST route for the currently queried object.
 *
 * @since 5.5.0
 *
 * @return string The REST route of the resource, or an empty string if no resource identified.
 */
function rest_get_queried_resource_route() {
	if ( is_singular() ) {
		$route = rest_get_route_for_post( get_queried_object() );
	} elseif ( is_category() || is_tag() || is_tax() ) {
		$route = rest_get_route_for_term( get_queried_object() );
	} elseif ( is_author() ) {
		$route = '/wp/v2/users/' . get_queried_object_id();
	} else {
		$route = '';
	}

	/**
	 * Filters the REST route for the currently queried object.
	 *
	 * @since 5.5.0
	 *
	 * @param string $link The route with a leading slash, or an empty string.
	 */
	return apply_filters( 'rest_queried_resource_route', $route );
}

/**
 * Retrieves an array of endpoint arguments from the item schema and endpoint method.
 *
 * @since 5.6.0
 *
 * @param array  $schema The full JSON schema for the endpoint.
 * @param string $method Optional. HTTP method of the endpoint. The arguments for `CREATABLE` endpoints are
 *                       checked for required values and may fall-back to a given default, this is not done
 *                       on `EDITABLE` endpoints. Default WP_REST_Server::CREATABLE.
 * @return array The endpoint arguments.
 */
function rest_get_endpoint_args_for_schema( $schema, $method = WP_REST_Server::CREATABLE ) {

	$schema_properties       = ! empty( $schema['properties'] ) ? $schema['properties'] : array();
	$endpoint_args           = array();
	$valid_schema_properties = rest_get_allowed_schema_keywords();
	$valid_schema_properties = array_diff( $valid_schema_properties, array( 'default', 'required' ) );

	foreach ( $schema_properties as $field_id => $params ) {

		// Arguments specified as `readonly` are not allowed to be set.
		if ( ! empty( $params['readonly'] ) ) {
			continue;
		}

		$endpoint_args[ $field_id ] = array(
			'validate_callback' => 'rest_validate_request_arg',
			'sanitize_callback' => 'rest_sanitize_request_arg',
		);

		if ( WP_REST_Server::CREATABLE === $method && isset( $params['default'] ) ) {
			$endpoint_args[ $field_id ]['default'] = $params['default'];
		}

		if ( WP_REST_Server::CREATABLE === $method && ! empty( $params['required'] ) ) {
			$endpoint_args[ $field_id ]['required'] = true;
		}

		foreach ( $valid_schema_properties as $schema_prop ) {
			if ( isset( $params[ $schema_prop ] ) ) {
				$endpoint_args[ $field_id ][ $schema_prop ] = $params[ $schema_prop ];
			}
		}

		// Merge in any options provided by the schema property.
		if ( isset( $params['arg_options'] ) ) {

			// Only use required / default from arg_options on CREATABLE endpoints.
			if ( WP_REST_Server::CREATABLE !== $method ) {
				$params['arg_options'] = array_diff_key(
					$params['arg_options'],
					array(
						'required' => '',
						'default'  => '',
					)
				);
			}

			$endpoint_args[ $field_id ] = array_merge( $endpoint_args[ $field_id ], $params['arg_options'] );
		}
	}

	return $endpoint_args;
}


/**
 * Converts an error to a response object.
 *
 * This iterates over all error codes and messages to change it into a flat
 * array. This enables simpler client behaviour, as it is represented as a
 * list in JSON rather than an object/map.
 *
 * @since 5.7.0
 *
 * @param WP_Error $error WP_Error instance.
 *
 * @return WP_REST_Response List of associative arrays with code and message keys.
 */
function rest_convert_error_to_response( $error ) {
	$status = array_reduce(
		$error->get_all_error_data(),
		static function ( $status, $error_data ) {
			return is_array( $error_data ) && isset( $error_data['status'] ) ? $error_data['status'] : $status;
		},
		500
	);

	$errors = array();

	foreach ( (array) $error->errors as $code => $messages ) {
		$all_data  = $error->get_all_error_data( $code );
		$last_data = array_pop( $all_data );

		foreach ( (array) $messages as $message ) {
			$formatted = array(
				'code'    => $code,
				'message' => $message,
				'data'    => $last_data,
			);

			if ( $all_data ) {
				$formatted['additional_data'] = $all_data;
			}

			$errors[] = $formatted;
		}
	}

	$data = $errors[0];
	if ( count( $errors ) > 1 ) {
		// Remove the primary error.
		array_shift( $errors );
		$data['additional_errors'] = $errors;
	}

	return new WP_REST_Response( $data, $status );
}