<?php

if ($config['enable_bgp']) {
    // Discover BGP peers
    echo 'BGP Sessions : ';

    $bgpLocalAs = trim(snmp_walk($device, '.1.3.6.1.2.1.15.2', '-Oqvn', 'BGP4-MIB', $config['mibdir']));

    if (is_numeric($bgpLocalAs)) {
        echo "AS$bgpLocalAs ";

        if ($bgpLocalAs != $device['bgpLocalAs']) {
            dbUpdate(array('bgpLocalAs' => $bgpLocalAs), 'devices', 'device_id=?', array($device['device_id']));
            echo 'Updated AS ';
        }

        $peer2      = false;
        $peers_data = snmp_walk($device, 'cbgpPeer2RemoteAs', '-Oq', 'CISCO-BGP4-MIB', $config['mibdir']);
        if (empty($peers_data)) {
            $peers_data = snmp_walk($device, 'BGP4-MIB::bgpPeerRemoteAs', '-Oq', 'BGP4-MIB', $config['mibdir']);
        }
        else {
            $peer2 = true;
        }

        d_echo("Peers : $peers_data \n");

        $peers = trim(str_replace('CISCO-BGP4-MIB::cbgpPeer2RemoteAs.', '', $peers_data));
        $peers = trim(str_replace('BGP4-MIB::bgpPeerRemoteAs.', '', $peers));

        foreach (explode("\n", $peers) as $peer) {
            if ($peer2 === true) {
                list($ver, $peer) = explode('.', $peer, 2);
            }

            list($peer_ip, $peer_as) = explode(' ', $peer);
            if (strstr($peer_ip, ':')) {
                $peer_ip_snmp = preg_replace('/:/', ' ', $peer_ip);
                $peer_ip      = preg_replace('/(\S+\s+\S+)\s/', '$1:', $peer_ip_snmp);
                $peer_ip      = str_replace('"', '', str_replace(' ', '', $peer_ip));
            }

            if ($peer && $peer_ip != '0.0.0.0') {
                d_echo("Found peer $peer_ip (AS$peer_as)\n");

                $peerlist[] = array(
                    'ip'  => $peer_ip,
                    'as'  => $peer_as,
                    'ver' => $ver,
                );
            }
        }

        if ($device['os'] == 'junos') {
            // Juniper BGP4-V2 MIB
            // FIXME: needs a big cleanup! also see below.
            // FIXME: is .0.ipv6 the only possible value here?
            $result = snmp_walk($device, 'jnxBgpM2PeerRemoteAs.0.ipv6', '-Onq', 'BGP4-V2-MIB-JUNIPER', $config['install_dir'].'/mibs/junos');
            $peers  = trim(str_replace('.1.3.6.1.4.1.2636.5.1.1.2.1.1.1.13.0.', '', $result));
            foreach (explode("\n", $peers) as $peer) {
                list($peer_ip_snmp, $peer_as) = explode(' ', $peer);

                // Magic! Basically, takes SNMP form and finds peer IPs from the walk OIDs.
                $peer_ip = Net_IPv6::compress(snmp2ipv6(implode('.', array_slice(explode('.', $peer_ip_snmp), (count(explode('.', $peer_ip_snmp)) - 16)))));

                if ($peer) {
                    d_echo("Found peer $peer_ip (AS$peer_as)\n");

                    $peerlist[] = array(
                        'ip' => $peer_ip,
                        'as' => $peer_as,
                    );
                }
            }
        }
    }
    else {
        echo 'No BGP on host';
        if ($device['bgpLocalAs']) {
            dbUpdate(array('bgpLocalAs' => 'NULL'), 'devices', 'device_id=?', array($device['device_id']));
            echo ' (Removed ASN) ';
        }
    }

    // Process disovered peers
    if (isset($peerlist)) {
        foreach ($peerlist as $peer) {
            $astext = get_astext($peer['as']);

            if (dbFetchCell('SELECT COUNT(*) from `bgpPeers` WHERE device_id = ? AND bgpPeerIdentifier = ?', array($device['device_id'], $peer['ip'])) < '1') {
                $add = dbInsert(array('device_id' => $device['device_id'], 'bgpPeerIdentifier' => $peer['ip'], 'bgpPeerRemoteAs' => $peer['as']), 'bgpPeers');
                if ($config['autodiscovery']['bgp'] === true) {
                    $name             = gethostbyaddr($peer['ip']);
                    $remote_device_id = discover_new_device($name, $device, 'BGP');
                }

                echo '+';
            }
            else {
                $update = dbUpdate(array('bgpPeerRemoteAs' => $peer['as'], 'astext' => mres($astext)), 'bgpPeers', 'device_id=? AND bgpPeerIdentifier=?', array($device['device_id'], $peer['ip']));
                echo '.';
            }

            if ($device['os_group'] == 'cisco' || $device['os'] == 'junos') {
                if ($device['os_group'] == 'cisco') {
                    // Get afi/safi and populate cbgp on cisco ios (xe/xr)
                    unset($af_list);

                    if ($peer2 === true) {
                        $af_data = snmpwalk_cache_oid($device, 'cbgpPeer2AddrFamilyEntry', $cbgp, 'CISCO-BGP4-MIB', $config['mibdir']);
                    }
                    else {
                        $af_data = snmpwalk_cache_oid($device, 'cbgpPeerAddrFamilyEntry', $cbgp, 'CISCO-BGP4-MIB', $config['mibdir']);
                    }

                    d_echo('afi data :: ');
                    d_echo($af_data);

                    foreach ($af_data as $k => $v) {
                        if ($peer2 === true) {
                            list(,$k) = explode('.', $k, 2);
                        }

                        d_echo("AFISAFI = $k\n");

                        $afisafi_tmp = explode('.', $k);
                        $safi        = array_pop($afisafi_tmp);
                        $afi         = array_pop($afisafi_tmp);
                        $bgp_ip      = str_replace(".$afi.$safi", '', $k);
                        $bgp_ip      = preg_replace('/:/', ' ', $bgp_ip);
                        $bgp_ip      = preg_replace('/(\S+\s+\S+)\s/', '$1:', $bgp_ip);
                        $bgp_ip      = str_replace('"', '', str_replace(' ', '', $bgp_ip));
                        if ($afi && $safi && $bgp_ip == $peer['ip']) {
                            $af_list[$bgp_ip][$afi][$safi] = 1;
                            if (dbFetchCell('SELECT COUNT(*) from `bgpPeers_cbgp` WHERE device_id = ? AND bgpPeerIdentifier = ?, AND afi=? AND safi=?', array($device['device_id'], $peer['ip'], $afi, $safi)) == 0) {
                                dbInsert(array('device_id' => $device['device_id'], 'bgpPeerIdentifier' => $peer['ip'], 'afi' => $afi, 'safi' => $safi), 'bgpPeers_cbgp');
                            }
                        }
                    }
                }

                if ($device['os'] == 'junos') {
                    $safis[1] = 'unicast';
                    $safis[2] = 'multicast';

                    if (!isset($j_peerIndexes)) {
                        $j_bgp = snmpwalk_cache_multi_oid($device, 'jnxBgpM2PeerTable', $jbgp, 'BGP4-V2-MIB-JUNIPER', $config['install_dir'].'/mibs/junos');

                        foreach ($j_bgp as $index => $entry) {
                            switch ($entry['jnxBgpM2PeerRemoteAddrType']) {
                                case 'ipv4':
                                    $ip = long2ip(hexdec($entry['jnxBgpM2PeerRemoteAddr']));
                                    d_echo("peerindex for ipv4 $ip is ".$entry['jnxBgpM2PeerIndex']."\n");

                                    $j_peerIndexes[$ip] = $entry['jnxBgpM2PeerIndex'];
                                    break;

                                case 'ipv6':
                                    $ip6 = trim(str_replace(' ', '', $entry['jnxBgpM2PeerRemoteAddr']), '"');
                                    $ip6 = substr($ip6, 0, 4).':'.substr($ip6, 4, 4).':'.substr($ip6, 8, 4).':'.substr($ip6, 12, 4).':'.substr($ip6, 16, 4).':'.substr($ip6, 20, 4).':'.substr($ip6, 24, 4).':'.substr($ip6, 28, 4);
                                    $ip6 = Net_IPv6::compress($ip6);
                                    d_echo("peerindex for ipv6 $ip6 is ".$entry['jnxBgpM2PeerIndex']."\n");

                                    $j_peerIndexes[$ip6] = $entry['jnxBgpM2PeerIndex'];
                                    break;

                                default:
                                    echo "HALP? Don't know RemoteAddrType ".$entry['jnxBgpM2PeerRemoteAddrType']."!\n";
                                    break;
                            }
                        }
                    }

                    if (!isset($j_afisafi)) {
                        $j_prefixes = snmpwalk_cache_multi_oid($device, 'jnxBgpM2PrefixCountersTable', $jbgp, 'BGP4-V2-MIB-JUNIPER', $config['install_dir'].'/mibs/junos');
                        foreach (array_keys($j_prefixes) as $key) {
                            list($index,$afisafi) = explode('.', $key, 2);
                            $j_afisafi[$index][]  = $afisafi;
                        }
                    }

                    foreach ($j_afisafi[$j_peerIndexes[$peer['ip']]] as $afisafi) {
                        list ($afi,$safi)     = explode('.', $afisafi);
                        $safi                 = $safis[$safi];
                        $af_list[$afi][$safi] = 1;
                        if (dbFetchCell('SELECT COUNT(*) from `bgpPeers_cbgp` WHERE device_id = ? AND bgpPeerIdentifier = ?, AND afi=? AND safi=?', array($device['device_id'], $peer['ip'], $afi, $safi)) == 0) {
                            dbInsert(array('device_id' => $device['device_id'], 'bgpPeerIdentifier' => $peer['ip'], 'afi' => $afi, 'safi' => $safi), 'bgpPeers_cbgp');
                        }
                    }
                }

                $af_query = "SELECT * FROM bgpPeers_cbgp WHERE `device_id` = '".$device['device_id']."' AND bgpPeerIdentifier = '".$peer['ip']."'";
                foreach (dbFetchRows($af_query) as $entry) {
                    $afi  = $entry['afi'];
                    $safi = $entry['safi'];
                    if (!$af_list[$afi][$safi] || !$af_list[$entry['bgpPeerIdentifier']][$afi][$safi]) {
                        dbDelete('bgpPeers_cbgp', '`device_id` = ? AND `bgpPeerIdentifier` = ?, afi=?, safi=?', array($device['device_id'], $peer['ip'], $afi, $safi));
                    }
                }
            }
        }

        unset($j_afisafi);
        unset($j_prefixes);
        unset($j_bgp);
        unset($j_peerIndexes);
    }

    // Delete removed peers
    $sql = "SELECT * FROM bgpPeers AS B, devices AS D WHERE B.device_id = D.device_id AND D.device_id = '".$device['device_id']."'";

    foreach (dbFetchRows($sql) as $entry) {
        unset($exists);
        $i = 0;

        while ($i < count($peerlist) && !isset($exists)) {
            if ($peerlist[$i]['ip'] == $entry['bgpPeerIdentifier']) {
                $exists = 1;
            }

            $i++;
        }

        if (!isset($exists)) {
            dbDelete('bgpPeers', '`bgpPeer_id` = ?', array($entry['bgpPeer_id']));
            dbDelete('bgpPeers_cbgp', '`bgpPeer_id` = ?', array($entry['bgpPeer_id']));
            echo '-';
        }
    }

    unset($peerlist);

    echo "\n";
}