<?php
/*
 * LibreNMS module to capture statistics from the CISCO-NTP-MIB
 *
 * Copyright (c) 2016 Aaron Daniels <aaron@daniels.id.au>
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.  Please see LICENSE.txt at the top level of
 * the source code distribution for details.
 */

use LibreNMS\Enum\IntegerType;
use LibreNMS\RRD\RrdDefinition;
use LibreNMS\Util\Number;

$tmp_module = 'ntp';

$component = new LibreNMS\Component();
$options = [];
$options['filter']['type'] = ['=', $tmp_module];
$options['filter']['disabled'] = ['=', 0];
$options['filter']['ignore'] = ['=', 0];

// We only care about our device id.
$components = $component->getComponents($device['device_id'], $options)[$device['device_id']] ?? null;

// Only collect SNMP data if we have enabled components
if (is_array($components) && count($components) > 0) {
    // Let's gather the stats..
    $cntpPeersVarEntry = snmpwalk_array_num($device, '.1.3.6.1.4.1.9.9.168.1.2.1.1', 2);

    // Loop through the components and extract the data.
    foreach ($components as $key => &$array) {
        $peer = $array['peer'];

        // Let's make sure the rrd is setup for this class.
        $rrd_name = ['ntp', $peer];
        $rrd_def = RrdDefinition::make()
            ->addDataset('stratum', 'GAUGE', 0)
            ->addDataset('offset', 'GAUGE', 0)
            ->addDataset('delay', 'GAUGE', 0)
            ->addDataset('dispersion', 'GAUGE', 0);

        $array['stratum'] = $cntpPeersVarEntry['1.3.6.1.4.1.9.9.168.1.2.1.1'][9][$array['UID']];
        // Set the status, 16 = Bad
        if ($array['stratum'] == 16) {
            $array['status'] = 2;
            $array['error'] = 'NTP is not in sync';
        } else {
            $array['status'] = 0;
            $array['error'] = '';
        }

        // Extract the statistics and update rrd
        $rrd['stratum'] = $array['stratum'];

        // Cisco NTPSignedTimeValue - 16 bits of signedint, and 16 bits of unsignedint for fractional
        // The time in seconds that could represent signed quantities like time delay with respect to some
        // source. This textual-convention is specific to Cisco implementation of NTP where 32-bit integers are
        // used for such quantities. The signed integer part is in the first 16 bits and the fraction part is in
        // the last 16 bits.

        $hexoffset = $cntpPeersVarEntry['1.3.6.1.4.1.9.9.168.1.2.1.1'][23][$array['UID']];
        $rrd['offset'] = Number::constrainInteger(hexdec(substr($hexoffset, 0, 5)), IntegerType::int16) + hexdec(substr($hexoffset, -5)) / 65536;

        $hexdelay = $cntpPeersVarEntry['1.3.6.1.4.1.9.9.168.1.2.1.1'][24][$array['UID']];
        $rrd['delay'] = Number::constrainInteger(hexdec(substr($hexdelay, 0, 5)), IntegerType::int16) + hexdec(substr($hexdelay, -5)) / 65536;

        // Cisco NTPUnsignedTimeValue - 16 bits of unsignedint, and 16 bits of unsignedint for fractional
        $hexdisp = $cntpPeersVarEntry['1.3.6.1.4.1.9.9.168.1.2.1.1'][25][$array['UID']];
        $rrd['dispersion'] = hexdec(substr($hexdisp, 0, 5)) + hexdec(substr($hexdisp, -5)) / 65536;

        $tags = compact('ntp', 'rrd_name', 'rrd_def', 'peer');
        data_update($device, 'ntp', $tags, $rrd);

        // Let's print some debugging info.
        d_echo("\n\nComponent: " . $key . "\n");
        d_echo('    Index:      ' . $array['UID'] . "\n");
        d_echo('    Peer:       ' . $array['peer'] . ':' . $array['port'] . "\n");
        d_echo('    Stratum:    1.3.6.1.4.1.9.9.168.1.2.1.1.9.' . $array['UID'] . '  = ' . $rrd['stratum'] . "\n");
        d_echo('    Offset:     1.3.6.1.4.1.9.9.168.1.2.1.1.23.' . $array['UID'] . ' = ' . $rrd['offset'] . "\n");
        d_echo('    Delay:      1.3.6.1.4.1.9.9.168.1.2.1.1.24.' . $array['UID'] . ' = ' . $rrd['delay'] . "\n");
        d_echo('    Dispersion: 1.3.6.1.4.1.9.9.168.1.2.1.1.25.' . $array['UID'] . ' = ' . $rrd['dispersion'] . "\n");

        // Clean-up after yourself!
        unset($filename, $rrd_filename, $rrd);
    } // End foreach components

    // Write the Components back to the DB.
    $component->setComponentPrefs($device['device_id'], $components);
} // end if count components

// Clean-up after yourself!
unset($type, $components, $component, $options, $tmp_module);
