2b2t queue.php

<?php
const DB_FILE = '2b2t_queue.db';
const ENDPOINT_MAGIC = '69042'; // nice

$db = new SQLite3(DB_FILE);

if (isset($_POST['update']) && $_POST['auth'] == ENDPOINT_MAGIC) {
    // update mode
    $ts = intval($_POST['ts']);
    $qp = intval($_POST['qp']);
    $ret = $db->query('SELECT seq, qp FROM `2b2q_log` ORDER BY id DESC LIMIT 1')->fetchArray();
    $seq = $ret[0];
    $last_qp = $ret[1];
    if ($last_qp < $qp) {
        $seq++;
    }
    $stmt = $db->prepare('INSERT INTO `2b2q_log` (seq, ts, qp) VALUES (:seq, :ts, :qp)');
    $stmt->bindValue(':seq', $seq);
    $stmt->bindValue(':ts', $ts);
    $stmt->bindValue(':qp', $qp);
    $stmt->execute();
    header('HTTP/1.0 204 No Content');
} else {
    // stats mode
    $now = time();
    $last_seq = $db->query('SELECT seq FROM `2b2q_log` ORDER BY id DESC LIMIT 1')->fetchArray()[0];
    $ret = $db->query("SELECT MIN(id), MAX(id) FROM `2b2q_log` WHERE seq = $last_seq")->fetchArray();
    $first_id = $ret[0];
    $last_id = $ret[1];
    if ($first_id == $last_id) {
        die('Insufficient data');
    }
    $ret = $db->query("SELECT ts, qp FROM `2b2q_log` WHERE id = $first_id")->fetchArray();
    $initial_ts = $ret[0];
    $initial_qp = $ret[1];
    $ret = $db->query("SELECT ts, qp FROM `2b2q_log` WHERE id = $last_id")->fetchArray();
    $current_ts = $ret[0];
    $current_qp = $ret[1];
    // don't divide by zero dummy
    if ($initial_ts == $current_ts || $initial_qp == $current_qp) {
        die('Insufficient data');
    }
    // linear regression using only two points isn't that great, the head of the queue moves slower
    $est_total_wait = $current_qp * ($current_ts - $initial_ts) / ($initial_qp - $current_qp);
    $est_remaining_wait = $initial_ts + $est_total_wait - $now;
    if ($est_remaining_wait < 0) {
        $est_remaining_wait = 0;
    }
?><head>
<meta charset="utf-8">
<meta http-equiv="Refresh" content="60">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>2b2t Queue Info</title>
</head>
<body>
<p>Last update: <?= date(DATE_RFC1123, $current_ts); ?></p>
<p>Queue position: <?= $current_qp ?></p>
<p>Estimated wait time: <?= round($est_remaining_wait / 60) ?> minutes</p>
</body>
<?php
} // end else

$db->close();