<?php
/**
* This file is part of the ramsey/uuid library
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*
* @copyright Copyright (c) Ben Ramsey <ben@benramsey.com>
* @license http://opensource.org/licenses/MIT MIT
* @link https://benramsey.com/projects/ramsey-uuid/ Documentation
* @link https://packagist.org/packages/ramsey/uuid Packagist
* @link https://github.com/ramsey/uuid GitHub
*/

namespace Ramsey\Uuid\Provider\Node;

use Ramsey\Uuid\Provider\NodeProviderInterface;

/**
* SystemNodeProvider provides functionality to get the system node ID (MAC
* address) using external system calls
*/
class SystemNodeProvider implements NodeProviderInterface
{
/**
* Returns the system node ID
*
* @return string|false System node ID as a hexadecimal string, or false if it is not found
*/
public function getNode()
{
static $node = null;

if ($node !== null) {
return $node;
}

$pattern = '/[^:]([0-9A-Fa-f]{2}([:-])[0-9A-Fa-f]{2}(\2[0-9A-Fa-f]{2}){4})[^:]/';
$matches = array();

// first try a linux specific way
$node = $this->getSysfs();

// Search the ifconfig output for all MAC addresses and return
// the first one found
if ($node === false) {
if (preg_match_all($pattern, $this->getIfconfig(), $matches, PREG_PATTERN_ORDER)) {
$node = $matches[1][0];
}
}
if ($node !== false) {
$node = str_replace([':', '-'], '', $node);
}
return $node;
}

/**
* Returns the network interface configuration for the system
*
* @codeCoverageIgnore
* @return string
*/
protected function getIfconfig()
{
if (strpos(strtolower(ini_get('disable_functions')), 'passthru') !== false) {
return '';
}

ob_start();
switch (strtoupper(substr(php_uname('a'), 0, 3))) {
case 'WIN':
passthru('ipconfig /all 2>&1');
break;
case 'DAR':
passthru('ifconfig 2>&1');
break;
case 'FRE':
passthru('netstat -i -f link 2>&1');
break;
case 'LIN':
default:
passthru('netstat -ie 2>&1');
break;
}

return ob_get_clean();
}

/**
* Returns mac address from the first system interface via the sysfs interface
*
* @return string|bool
*/
protected function getSysfs()
{
$mac = false;

if (strtoupper(php_uname('s')) === 'LINUX') {
$addressPaths = glob('/sys/class/net/*/address', GLOB_NOSORT);

if (empty($addressPaths)) {
return false;
}

array_walk($addressPaths, function ($addressPath) use (&$macs) {
$macs[] = file_get_contents($addressPath);
});

$macs = array_map('trim', $macs);

// remove invalid entries
$macs = array_filter($macs, function ($mac) {
return
// localhost adapter
$mac !== '00:00:00:00:00:00' &&
// must match mac adress
preg_match('/^([0-9a-f]{2}:){5}[0-9a-f]{2}$/i', $mac);
});

$mac = reset($macs);
}

return $mac;
}
}