AdguardHome HOSTS file generator

hosts.php

<?php
header('Content-Type: text/plain; charset=utf-8');
require("../.config.php"); // contains $servers array
if (isset($_GET["dl"])) header('Content-Disposition: attachment; filename="hosts"');
function update_keypair(/* map[string,mixed] */ $array, /* string */ $key, /* string */ $value) {
    if (!isset($array[$key])) {
        $array[$key] = array($value);
    } else {
        if (!in_array($value, $array[$key])) {
            $array[$key][] = $value;
        }
    }
    return $array;
}

$rewrites = json_decode(file_get_contents($servers[0]."/rewrite/list"));

$hosts = array();

foreach ($rewrites as $rewrite) {
    $key = trim($rewrite->answer);
    if(filter_var($key, FILTER_VALIDATE_IP) === false) {
        continue;
        $key = "# " . $key;
    }
    $value = trim($rewrite->domain);
    if (!preg_match('/^[a-z0-9.\*_\-]+$/i', $value)) continue;
    if (filter_var($value, FILTER_VALIDATE_IP) === true) continue;
    $hosts = update_keypair($hosts, $key, $value);
}

$date = date('Y-m-d H:i:s');
$separator = str_repeat('#', 50);
printf("%s\n# ADGUARD HOME HOSTS FILE GENERATED AT %s\n%s\n", $separator, $date, $separator);
ksort($hosts);
$maxIpLength = max(array_map('strlen', array_keys($hosts)));
foreach ($hosts as $ip => $domains) {
    $formattedIp = str_pad($ip, $maxIpLength, ' ');
    asort($domains);
    printf("%s\t%s\n", $formattedIp, implode("\t", $domains));
}
?>