Simple VOD HLS Loop in PHP

vod-hls-loop.php

<?php

header("Content-Type: application/x-mpegURL");
header("Content-Disposition: attachment; filename=index.m3u8");

$target_duration = 10;
$segments_total  = 93;
$segments_live   = 5;
$segment_path    = "%03d.ts";
$start_offset    = 0; // starts with 000.ts
$start_time      = strtotime("19 May 2021");

$media_sequence = intval((time() - $start_time) / $target_duration);

echo <<<M3U8
#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:${target_duration}
#EXT-X-MEDIA-SEQUENCE:${media_sequence}
M3U8;

for ($i=0;$i<$segments_live;$i++) {
    $segment_id = ($media_sequence + $i) % $segments_total;
    if ($segment_id == 0) echo "\n", "#EXT-X-DISCONTINUITY";
    echo "\n", "#EXTINF:${target_duration},";
    echo "\n", sprintf($segment_path, $segment_id + $start_offset);
}