<?php

namespace App\Support\WoltGuard;

use Illuminate\Support\Facades\DB;

trait Probes
{
    protected function check(string $source): bool
    {
        if (str_starts_with($source, 'systemd:'))   return $this->probeSystemd(substr($source, 8));
        if (str_starts_with($source, 'tcp:'))       return $this->probeTcp(...$this->splitTcp(substr($source, 4)));
        if (str_starts_with($source, 'socket:'))    return @file_exists(substr($source, 7));
        if (str_starts_with($source, 'pid:'))       return $this->probePid(substr($source, 4));
        if (str_starts_with($source, 'proc:'))      return $this->probeProcessRegex(substr($source, 5));
        if ($source === 'db')                       return $this->probeDatabase();
        return false;
    }

    protected function splitTcp(string $s): array { [$h,$p] = explode(':', $s, 2); return [$h,(int)$p]; }

    protected function probeSystemd(string $unit): bool
    {
        $bin = file_exists('/bin/systemctl') ? '/bin/systemctl'
            : (file_exists('/usr/bin/systemctl') ? '/usr/bin/systemctl' : 'systemctl');
        $cmd = sprintf('%s is-active --quiet %s 2>/dev/null', escapeshellcmd($bin), escapeshellarg($unit));
        $exit = null; @exec($cmd, $_, $exit);
        return $exit === 0;
    }

    protected function probeTcp(string $host, int $port, int $timeout = 1): bool
    {
        $fp = @fsockopen($host, $port, $e1, $e2, $timeout);
        if (is_resource($fp)) { fclose($fp); return true; }
        return false;
    }

    protected function probePid(string $path): bool
    {
        if (!@is_file($path)) return false;
        $pid = (int) trim(@file_get_contents($path) ?: '');
        return $pid > 1 && @posix_kill($pid, 0);
    }

    protected function probeProcessRegex(string $regex): bool
    {
        $regex = '#' . $regex . '#i';
        foreach (@scandir('/proc') ?: [] as $d) {
            if (!ctype_digit($d)) continue;
            $cmd = @file_get_contents("/proc/$d/cmdline");
            if (!$cmd) continue;
            $cmd = str_replace("\0", ' ', $cmd);
            if (preg_match($regex, $cmd)) return true;
        }
        return false;
    }

    protected function probeDatabase(): bool
    {
        try { DB::connection()->getPdo(); return true; }
        catch (\Throwable) { return false; }
    }
}