Cacher is the code snippet organizer for pro developers

<?php
header('Content-Type: application:json');
header("Access-Control-Allow-Origin: *");

/* CONFIG - EDIT THESE VARIABLEs TO YOUR HEART'S CONTENT */

$shirt_url = 'https://cottonbureau.com/products/your-shirt';
$cache_duration = 60; // in minutes

$notification_email = 'test@test.com';
$notification_from_header = 'From: CB Notification <no-reply@your-spf-safe-domain.com>';

/* NOPE - DON'T EDIT ANYTHING BELOW THIS LINE! */

function trim_data($content, $str_start, $str_end) {
  $t_length = strlen($str_start);
  $start = strpos($content, $str_start) + $t_length;
  $end = strpos($content, $str_end, $start);
  $length = $end - $start;
  $data = substr($content, $start, $length) ? substr($content, $start, $length) : null;

  return $data;
} 

function curl_download($Url){
  if (!function_exists('curl_init')){
    die('cURL is not installed. Install and try again.');
  }

  $ch = curl_init();
  curl_setopt($ch, CURLOPT_URL, $Url);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
  $output = curl_exec($ch);
  curl_close($ch);

  $sold = trim_data($output, 'data-sold="', '"');
  $days_left = trim_data($output, '<span class="Meter-num">', '</span');
  $return = array(
    'sold' => $sold,
    'days_left' => $days_left);
  $return['meta']['cached'] = true;
  $return['meta']['cache_time'] = date("Y-m-d H:i:s");
  return $return;
}

$json = json_decode( file_get_contents('cb.json') );
$current_time = new DateTime('now');
$cache_time = new DateTime($json->meta->cache_time);
$interval = $current_time->diff($cache_time, true);

if ( $interval->i > $cache_duration ) :
  $cb = curl_download( $shirt_url );

  chmod('cb.json', 0777);
  file_put_contents('cb.json', json_encode($cb));
  chmod('cb.json', 0664);

  echo json_encode($cb);

  $cb['meta']['cached'] = false;
  
  if ( $json->sold !== $cb['sold'] ) :
    $address = $notification_email;
    $subject = sprintf('CB Shirt Update: %s', $cb['sold']);
    $msg = sprintf('You’re up to %s shirts!', $cb['sold']);
    $from = $notification_from_header;
    mail($address, $subject, $msg, $from);
  endif;
else :
  echo file_get_contents('cb.json');
endif;
?>