Validate a value based on a schema.

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;
}