<?php declare(strict_types=1);
/**
 * Syslog wrapper
 *
 * @package wp-fail2ban
 * @since   4.4.0   Require PHP 7.4
 * @since   4.3.4.0
 */
namespace org\lecklider\charles\wordpress\wp_fail2ban;

use function org\lecklider\charles\wordpress\wp_fail2ban\core\remote_addr;

defined( 'ABSPATH' ) or exit;

abstract class Syslog {

	/**
	 * Helper: Build tag part
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @return string
	 */
	protected static function getTag(): string {
		return ( Config::get( 'WP_FAIL2BAN_SYSLOG_SHORT_TAG' ) )
			? 'wp'
			: 'wordpress'; // phpcs:ignore WordPress.WP.CapitalPDangit
	}

	/**
	 * Helper: Build host part
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @return string
	 */
	protected static function getHost(): string {
		$host = ( array_key_exists( 'WP_FAIL2BAN_HTTP_HOST', $_ENV ) )
					? $_ENV['WP_FAIL2BAN_HTTP_HOST'] // @codeCoverageIgnore
					: $_SERVER['HTTP_HOST'];

		if ( is_multisite() && ! SUBDOMAIN_INSTALL ) {
			if ( ! is_main_site() ) {
				$blog  = get_blog_details( get_current_blog_id(), false );
				$host .= '/' . trim( $blog->path, '/' );
			}
		}

		/**
		 * Some varieties of syslogd have difficulty if $host is too long
		 *
		 * @since 3.5.0
		 */
		if ( 0 < ( $len = Config::get( 'WP_FAIL2BAN_TRUNCATE_HOST' ) ) ) {
			$host = substr( $host, 0, $len );
		}

		return $host;
	}

	/**
	 * Update list of last syslog messages
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @param  int    $level
	 * @param  string $msg
	 *
	 * @return void
	 *
	 * @codeCoverageIgnore
	 */
	protected static function updateLastMessages( int $level, string $msg ): void {
		if ( ! Config::get( 'WP_FAIL2BAN_DISABLE_LAST_LOG' ) ) {
			if ( ! is_array( $last_messages = get_site_option( 'wp-fail2ban-messages', array() ) ) ) {
				$last_messages = array();
			}
			$message = array(
				'dt'  => gmdate( 'Y-m-d H:i:s' ),
				'lvl' => ConvertData::intToSyslogPriorityName( $level ),
				'msg' => $msg,
			);
			array_unshift( $last_messages, $message );
			$last_messages = array_slice( $last_messages, 0, 5 );
			update_site_option( 'wp-fail2ban-messages', $last_messages );
		}
	}

	/**
	 * Open
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @param  string $log
	 *
	 * @return bool
	 */
	public static function open( string $log = 'WP_FAIL2BAN_AUTH_LOG' ): bool {
		$options  = Config::get( 'WP_FAIL2BAN_OPENLOG_OPTIONS' );
		$facility = Config::get( $log );

		$ident = self::getTag();
		if ( Config::get( 'WP_FAIL2BAN_SYSLOG_TAG_HOST' ) ) {
			$host   = self::getHost();
			$ident .= "($host)";
		}

		if ( null !== ( $rv = apply_filters( __METHOD__, null, $ident, $options, $facility ) ) ) {
			return $rv;
		}

		if ( false === \openlog( $ident, $options, $facility ) ) {
			error_log( 'WPf2b: Cannot open syslog', 0 ); // @codeCoverageIgnore

		} else {
			if ( defined( 'WP_FAIL2BAN_TRACE' ) ) {
				error_log( 'WPf2b: Opened syslog', 0 ); // @codeCoverageIgnore
			}
			return true;
		}

		return false; // @codeCoverageIgnore
	}

	/**
	 * Write
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @param  int         $level
	 * @param  string      $msg
	 * @param  string|null $remote_addr
	 *
	 * @return bool
	 */
	public static function write( int $level, string $msg, string $remote_addr = null ): bool {
		$rv = false;

		if ( null === ( $rv = apply_filters( __METHOD__, null, $level, $msg, $remote_addr ) ) ) {
			$msg .= ' from ';
			$msg .= ( is_null( $remote_addr ) )
						? remote_addr()
						: $remote_addr;

			if ( false === ( $rv = \syslog( $level, $msg ) ) ) {
				error_log( "WPf2b: Cannot write to syslog: '{$msg}'", 0 ); // @codeCoverageIgnore
			} elseif ( defined( 'WP_FAIL2BAN_TRACE' ) ) {
				error_log( "WPf2b: Wrote to syslog: '{$msg}'", 0 ); // @codeCoverageIgnore
			}
		}

		self::updateLastMessages( $level, $msg );

		return $rv ?? false;
	}

	/**
	 * Close
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @return bool
	 */
	public static function close(): bool {
		if ( null === ( $rv = apply_filters( __FUNCTION__, null ) ) ) {
			$rv = \closelog();
		}

		return $rv;
	}

	/**
	 * Wrapper: write a single log entry
	 *
	 * @since  4.4.0    Add return type
	 * @since  4.3.4.0
	 *
	 * @param  int    $level      LOG_DEBUG|LOG_INFO|LOG_NOTICE|LOG_WARNING|LOG_ERR
	 * @param  string $msg
	 * @param  string $log
	 * @param  string $remote_addr
	 *
	 * @return bool
	 */
	public static function single( int $level, string $msg, string $log = 'WP_FAIL2BAN_AUTH_LOG', string $remote_addr = null ): bool {
		$rv = false;

		if ( self::open( $log ) ) {
			$rv = self::write( $level, $msg, $remote_addr );
			self::close();
		}

		return $rv;
	}
}