.pak file format of Quake game engine: PHP parsing library

<?php
// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

namespace {
    class QuakePak extends \Kaitai\Struct\Struct {
        public function __construct(\Kaitai\Struct\Stream $_io, \Kaitai\Struct\Struct $_parent = null, \QuakePak $_root = null) {
            parent::__construct($_io, $_parent, $_root);
            $this->_read();
        }

        private function _read() {
            $this->_m_magic = $this->_io->readBytes(4);
            if (!($this->magic() == "\x50\x41\x43\x4B")) {
                throw new \Kaitai\Struct\Error\ValidationNotEqualError("\x50\x41\x43\x4B", $this->magic(), $this->_io(), "/seq/0");
            }
            $this->_m_ofsIndex = $this->_io->readU4le();
            $this->_m_lenIndex = $this->_io->readU4le();
        }
        protected $_m_index;
        public function index() {
            if ($this->_m_index !== null)
                return $this->_m_index;
            $_pos = $this->_io->pos();
            $this->_io->seek($this->ofsIndex());
            $this->_m__raw_index = $this->_io->readBytes($this->lenIndex());
            $_io__raw_index = new \Kaitai\Struct\Stream($this->_m__raw_index);
            $this->_m_index = new \QuakePak\IndexStruct($_io__raw_index, $this, $this->_root);
            $this->_io->seek($_pos);
            return $this->_m_index;
        }
        protected $_m_magic;
        protected $_m_ofsIndex;
        protected $_m_lenIndex;
        protected $_m__raw_index;
        public function magic() { return $this->_m_magic; }
        public function ofsIndex() { return $this->_m_ofsIndex; }
        public function lenIndex() { return $this->_m_lenIndex; }
        public function _raw_index() { return $this->_m__raw_index; }
    }
}

namespace QuakePak {
    class IndexStruct extends \Kaitai\Struct\Struct {
        public function __construct(\Kaitai\Struct\Stream $_io, \QuakePak $_parent = null, \QuakePak $_root = null) {
            parent::__construct($_io, $_parent, $_root);
            $this->_read();
        }

        private function _read() {
            $this->_m_entries = [];
            $i = 0;
            while (!$this->_io->isEof()) {
                $this->_m_entries[] = new \QuakePak\IndexEntry($this->_io, $this, $this->_root);
                $i++;
            }
        }
        protected $_m_entries;
        public function entries() { return $this->_m_entries; }
    }
}

namespace QuakePak {
    class IndexEntry extends \Kaitai\Struct\Struct {
        public function __construct(\Kaitai\Struct\Stream $_io, \QuakePak\IndexStruct $_parent = null, \QuakePak $_root = null) {
            parent::__construct($_io, $_parent, $_root);
            $this->_read();
        }

        private function _read() {
            $this->_m_name = \Kaitai\Struct\Stream::bytesToStr(\Kaitai\Struct\Stream::bytesTerminate(\Kaitai\Struct\Stream::bytesStripRight($this->_io->readBytes(56), 0), 0, false), "UTF-8");
            $this->_m_ofs = $this->_io->readU4le();
            $this->_m_size = $this->_io->readU4le();
        }
        protected $_m_body;
        public function body() {
            if ($this->_m_body !== null)
                return $this->_m_body;
            $io = $this->_root()->_io();
            $_pos = $io->pos();
            $io->seek($this->ofs());
            $this->_m_body = $io->readBytes($this->size());
            $io->seek($_pos);
            return $this->_m_body;
        }
        protected $_m_name;
        protected $_m_ofs;
        protected $_m_size;
        public function name() { return $this->_m_name; }
        public function ofs() { return $this->_m_ofs; }
        public function size() { return $this->_m_size; }
    }
}