<?php declare(strict_types=1);
/**
 * IPv4/IPv6 Ranges Class
 *
 * @package wp-fail2ban
 * @since   5.0.0
 */
namespace org\lecklider\charles\wordpress\wp_fail2ban;

use org\lecklider\charles\wordpress\wp_fail2ban\premium\WPf2b;

/**
 * List of IP ranges.
 *
 * @since 5.0.0
 */
class IpRangeList implements \ArrayAccess, \Countable, \Iterator {

	/**
	 * @var   int   Iterator position.
	 * @since 5.0.0
	 */
	protected int $position = 0;

	/**
	 * @var   array|bool    IP Ranges.
	 * @since 5.0.0
	 */
	protected $ranges = false;

	/**
	 * Constructor.
	 *
	 * @since  5.0.0
	 *
	 * @param  array       $ranges
	 * @param  string|null $cacheTag
	 */
	public function __construct( array $ranges, string $cacheTag = null ) {
		$canCache = ( ! is_null( $cacheTag ) &&
					class_exists( __NAMESPACE__ . '\\premium\\WPf2b' ) &&
					WPf2b::can_use_premium_code() );
		if ( $canCache ) {
			$this->ranges = wp_cache_get( $cacheTag, WP_FAIL2BAN_CACHE );
		}
		if ( false === $this->ranges ) {
			$this->ranges = array();
			foreach ( $ranges as $range ) {
				$range = trim( $range );
				if ( empty( $range ) || '#' == $range[0] ) {
					continue;
				} else {
					$this->ranges[] = new IP( $range );
				}
			}
			if ( $canCache ) {
				wp_cache_set( $cacheTag, $this->ranges, WP_FAIL2BAN_CACHE );
			}
		}
	}

	/**
	 * Does the range contain the IP?
	 *
	 * @since  5.0.0
	 *
	 * @param  string|IP $ip
	 *
	 * @throws \InvalidArgumentException
	 *
	 * @return bool
	 */
	public function containsIP( $ip ): bool {
		if ( is_string( $ip ) ) {
			$bin = inet_pton( $ip );
			$ver = null;

		} elseif ( is_a( $ip, __NAMESPACE__ . '\IP' ) ) {
			$bin = $ip->getIpN();
			$ver = $ip->getVersion();

		} else {
			throw new \InvalidArgumentException( 'Must be string or IP.' );
		}

		return self::containsBinaryIP( $bin, $ver );
	}

	/**
	 * Does the range contain the IP? (Binary)
	 *
	 * @since  5.0.0
	 *
	 * @param  string   $binIP
	 * @param  int|null $version
	 *
	 * @return bool
	 */
	public function containsBinaryIP( $binIP, ?int $version = null ): bool {
		if ( is_null( $version ) ) {
			$version = ( 4 == strlen( $binIP ) ) ? 4 : 6;
		}
		foreach ( $this->ranges as $ipRange ) {
			if ( $version == $ipRange->getVersion() &&
				$ipRange->getIpN() == ( $binIP & $ipRange->getNetmaskN() ) ) {
				return true;
			}
		}
		return false;
	}


	//
	// ArrayAccess
	//

	/**
	 * ArrayAccess: offsetSet.
	 *
	 * @since  5.0.0
	 *
	 * @param  mixed $offset Key.
	 * @param  mixed $value  Value.
	 *
	 * @throw \RuntimeException
	 *
	 * @codeCoverageIgnore
	 * @SuppressWarnings(PHPMD.UnusedFormalParameter)
	 */
	public function offsetSet( $offset, $value ): void {
		throw new \RuntimeException( 'Lists are read-only' );
	}

	/**
	 * ArrayAccess: offsetExists.
	 *
	 * @since  5.0.0
	 *
	 * @param  mixed $offset Key.
	 * @return bool
	 *
	 * @codeCoverageIgnore
	 */
	public function offsetExists( $offset ): bool {
		return isset( $this->ranges[ $offset ] );
	}

	/**
	 * ArrayAccess: offsetUnset.
	 *
	 * @since  5.0.0
	 *
	 * @param mixed $offset Key.
	 *
	 * @throw \RuntimeException
	 *
	 * @codeCoverageIgnore
	 * @SuppressWarnings(PHPMD.UnusedFormalParameter)
	 */
	public function offsetUnset( $offset ): void {
		throw new \RuntimeException( 'Lists are read-only' );
	}

	/**
	 * ArrayAccess: offsetGet.
	 *
	 * @since  5.0.0
	 *
	 * @param  mixed $offset Key.
	 * @return bool
	 *
	 * @codeCoverageIgnore
	 */
	#[\ReturnTypeWillChange]
	public function offsetGet( $offset ): bool {
		return isset( $this->ranges[ $offset ] ) ? $this->ranges[ $offset ] : null;
	}


	//
	// Countable
	//

	/**
	 * Countable: count.
	 *
	 * @since  5.0.0
	 *
	 * @return int
	 *
	 * @codeCoverageIgnore
	 */
	public function count(): int {
		return count( $this->ranges );
	}


	//
	// Iterator
	//

	/**
	 * Iterator: rewind.
	 *
	 * @since  5.0.0
	 *
	 * @codeCoverageIgnore
	 */
	public function rewind(): void {
		$this->position = 0;
	}

	/**
	 * Iterator: current.
	 *
	 * @since  5.0.0
	 *
	 * @return mixed
	 *
	 * @codeCoverageIgnore
	 */
	#[\ReturnTypeWillChange]
	public function current() {
		return $this->ranges[ $this->position ];
	}

	/**
	 * Iterator: key.
	 *
	 * @since  5.0.0
	 *
	 * @return int
	 *
	 * @codeCoverageIgnore
	 */
	#[\ReturnTypeWillChange]
	public function key() {
		return $this->position;
	}

	/**
	 * Iterator: next.
	 *
	 * @since  5.0.0
	 *
	 * @codeCoverageIgnore
	 */
	public function next(): void {
		++$this->position;
	}

	/**
	 * Iterator: valid.
	 *
	 * @since  5.0.0
	 *
	 * @return bool
	 *
	 * @codeCoverageIgnore
	 */
	public function valid(): bool {
		return isset( $this->ranges[ $this->position ] );
	}
}