query("SELECT * FROM tanks WHERE 1 ORDER BY company_id ASC");
while ($row = $res->fetch_assoc()) {
// get last time it connected
$log_res = $db->query("SELECT * FROM tank_level_log WHERE tank_id = " . $row['record_id'] . " ORDER BY record_id DESC LIMIT 1");
if ($log_res->num_rows > 0) {
$log = $log_res->fetch_assoc();
echo $row['name'];
echo "
" . $date_last_connected = $log['date_time_measured'];
echo "
";
echo
$time_diff = strtotime("now + 2 hours") - strtotime($date_last_connected);
echo strtotime("now + 2 hours") . "
";
echo strtotime($date_last_connected) . "
";
echo $time_diff . "
";
// send email only if it's been a multiple of 15 minutes (with a small grace window, e.g., ±30s)
if ($time_diff >= 900) {
echo "Tank " . $row['name'] . " has not connected in the last 15 minutes\n";
$email_res = $db->query("SELECT * FROM email_notifications WHERE company_id = " . $row['company_id']);
if ($email_res->num_rows > 0) {
$emails = [];
$names = [];
while ($email_data = $email_res->fetch_assoc()) {
$emails[] = $email_data['email'];
$names[] = $email_data['name'];
}
$message = '
Tank ' . $row['name'] . ' has not connected in the last 15 minutes
Last Heartbeat: ' . $date_last_connected . '
';
$email->send_mail($emails, $names, $message, $row['name'] . " NOT CONNECTED");
}
}
}
}