Who squatting deh so?

squat.php

class SquatChecker
{
  public function find(array $domains = null, array $suspects = null): array
  {
    $domains = $domains ?? [
        'palantir.com',
        'apple.com',
        'nic.ci',
      ];

    $suspects = $suspects ?? [
        'pla@ntir.com',
        'plaantir.com',
        'aplantirtechnologies.com',
        'palanti.rbiz',
        'palantir.biz',
        'apple.org',
        'apple.com',
        'appleorchard.net',
        'paiantir.com',
        'nic.cl',
        'palantirtechnologies.com',
        'nlc.biz',
      ];

    $fakes = [
      'i' => ['1', 'l', '!', '|'],
      's' => ['5', '$'],
      '0' => '0',
      'a' => '@',
      'e' => '3',
    ];

    $squatters = [];

    foreach ($domains as $domain) {
      // Normalise domain with fakes
      $normalisedDomain = $domain;
      foreach ($fakes as $real => $fake) {
        $normalisedDomain = str_replace($fake, $real, $normalisedDomain);
      }

      foreach ($suspects as $suspectIndex => $suspect) {
        // Domains are identical, so not a squatter... next!
        if ($domain === $suspect) {
          continue;
        }

        // Normalise the suspect domain with fakes
        $normalisedSuspect = $suspect;
        foreach ($fakes as $real => $fake) {
          $normalisedSuspect = str_replace($fake, $real, $normalisedSuspect);
        }

        // Swap each pair of characters in the suspect domain and check for 
        // 2nd level domain name matches
        // Compare first without swapping to cover Task 1 and 2
        for ($i = 0; $i < (strpos($normalisedSuspect, '.') + 2); $i++) {
          $temp = $normalisedSuspect;

          if ($i > 0) {
            $temp[$i - 1] = $normalisedSuspect[$i];
            $temp[$i] = $normalisedSuspect[$i - 1];
          }

          echo $temp . PHP_EOL;
          if (substr($normalisedDomain, 0, strpos($normalisedDomain, '.')) === substr($temp, 0, strpos($temp, '.'))) {
            $squatters[] = $suspect;
            unset($suspects[$suspectIndex]);
            break;
          }
        }
      }
    }

    return $squatters;
  }
}

(new SquatChecker)->find();