Implement our own quicktime parser

app/Media/QuickTime/Atoms/moov/meta/ilst.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Media\QuickTime\Atoms\moov\meta;
+
+// Item LiST container atom
+
+use App\Media\QuickTime\Atoms\SubAtom;
+
+class ilst extends SubAtom
+{
+	public function __construct(int $offset,int $size,string $filename,?string $data)
+	{
+		parent::__construct($offset,$size,$filename);
+
+		$ptr = 0;
+		while ($ptr < strlen($data)) {
+			$key_size = unpack('Nsize',substr($data,$ptr,4));
+			// Sometimes atoms are terminated with a 0
+			if ($key_size['size'] === 0) {
+				$ptr += 4;
+				continue;
+			}
+
+			$a = unpack(sprintf('a4name/a%ddata',$key_size['size']-8),substr($data,$ptr+4,4+$key_size['size']-8));
+			$ptr += $key_size['size'];
+
+			// If we didnt get the right amount of data, something is wrong.
+			if (strlen($a['data']) < $key_size['size']-8)
+				break;
+
+			$b = unpack(sprintf('Nsize/a4name/a%ddata',strlen($a['data'])-8),$a['data']);
+
+			if ($b['name'] !== 'data')
+				throw new \Exception('Parsing of ILST got data that wasnt expected');
+			$c = unpack(sprintf('a4language/a4unknown/a%ddata',strlen($b['data'])-8),$b['data']);
+
+			// heirachy, name, size, offset
+			$this->cache = $this->cache->push($c['data']);
+		}
+	}
+}