vkontakte wall comments into subtitles (SBV)

vk-subtitles.php

#!/usr/bin/env php
<?php
$options = getopt('', [
	'url:',
	'first-comment-to:'
]);
if (empty($options['url']) || empty($options['first-comment-to'])) {
	exit('Parameters: --url=https://vk.com/sibhl?w=wall-96808993_127304 --first-comment-to=00:00:00'.PHP_EOL);
}

$url = parse_url($options['url']);
parse_str($url['query'], $query);
$wall = $query['w'];
preg_match('/^wall(.+)_(.+)$/', $wall, $m);
$ownerId = $m[1];
$postId = $m[2];

$apiUrl = sprintf(
	'https://api.vk.com/method/wall.getComments?owner_id=%d&post_id=%d&need_likes=0&count=100&preview_length=0&v=5.69',
	$ownerId,
	$postId
);

$response = file_get_contents($apiUrl);
$json = json_decode($response, true);

$items = $json['response']['items'];
$diff = null;
foreach ($items as $item) {
	if ($item['from_id'] != $ownerId) {
		continue;
	}
	$date = new DateTimeImmutable();
	$date = $date->setTimestamp($item['date']);
	
	if (null == $diff) {
		$date1 = new DateTime($date->format('H:i:s'));
		$date2 = new DateTime($options['first-comment-to']);
		$diff = $date2->diff($date1);
	}
	
	$date = $date->sub($diff);
	$writeTime = intval(mb_strlen($item['text']) / 2);
	$readTime = intval(mb_strlen($item['text']) / 5);
	$showTime = $writeTime + $readTime;
	
	echo $date->sub(DateInterval::createFromDateString($showTime.' seconds'))->format('H:i:s').",";
	echo $date->format('H:i:s')."\n";
	echo $item['text']."\n\n";
}

// 300 знаков в минуту, 5 знаков в секунду,  чтение
// 120 знаков в минуту, 2 знака в секунду, набор
// https://support.google.com/youtube/answer/2734698?hl=ru
// *.sbv формат
// ./vk-subtitles.php --url=https://vk.com/sibhl?w=wall-96808993_127304 --first-comment-to=00:00:59 > titles.sbv