PHP TibiaCam file reader

Simple reader for uncompressed TibiaCam files (binary files, up to 60MB).

It’s also example of fast reading binary data from file and handling it as stream.

<?php

class BinaryData
{
    /** @var resource */
    private $data;
    /** @var int */
    private $length;

    /**
     * BinaryData constructor.
     * @param string $data
     */
    public function __construct($data)
    {
        $this->data = fopen('php://memory', 'wb+');
        fwrite($this->data, $data);
        $this->length = ftell($this->data);
        rewind($this->data);
    }

    /**
     * @return int
     */
    public function getLength()
    {
        return $this->length;
    }

    /**
     * @return bool
     */
    public function isEof()
    {
        return ftell($this->data) == $this->length;
    }

    /**
     * @param int $length
     */
    public function skip($length)
    {
        fseek($this->data, $length, SEEK_CUR);
    }

    /**
     * @return int
     */
    public function getU8()
    {
        return unpack('C', fread($this->data, 1))[1];
    }

    /**
     * @return int
     */
    public function getU16()
    {
        return unpack('v', fread($this->data, 2))[1];
    }

    /**
     * @return int
     */
    public function getU32()
    {
        return unpack('V', fread($this->data, 4))[1];
    }

    /**
     * @return int
     */
    public function getU64()
    {
        return unpack('P', fread($this->data, 8))[1];
    }

    /**
     * @param int $length
     * @return string
     */
    public function getString($length = -1)
    {
        if ($length == -1) {
            $length = $this->getU16();
        }

        return fread($this->data, $length);
    }

}

class NetworkPacket extends BinaryData
{
    /**
     * 0x01 = packets sent to player
     * 0x03 = packets received from player
     * 0x05 = refresh packets for fast cam rewinding
     */
    const TYPE_OUT = 0x01;
    const TYPE_IN = 0x03;
    const TYPE_REFRESH = 0x05;

    /** @var int */
    private $type;

    /**
     * NetworkPacket constructor.
     * @param string $data
     */
    public function __construct($data)
    {
        parent::__construct($data);
        $this->type = $this->getU8();
    }

    /**
     * @return int
     */
    public function getType()
    {
        return $this->type;
    }

}

class Cam extends BinaryData
{
    /**
     * Cam constructor.
     * @param string $filePath path to cam file
     */
    public function __construct($filePath)
    {
        parent::__construct(file_get_contents($filePath));
    }

    /**
     * @return array
     */
    public function readTibiaCamAttributes()
    {
        $this->skip(8); // text: TIBIACAM

        $camVersion = $this->getU8();
        $playerId = $this->getU32();
        $playerName = $this->getString();
        $protocolVersion = $this->getU16();
        $timeCreated = $this->getU64();

        return [$camVersion, $playerId, $playerName, $protocolVersion, $timeCreated];
    }

}

$fileName = 'nowy.cam.ready';
$cam = new Cam($fileName);
$camAttributes = $cam->readTibiaCamAttributes();
var_dump($camAttributes);

while (!$cam->isEof()) {
    $packetTime = $cam->getU64();
    var_dump($packetTime);
    $packet = new NetworkPacket($cam->getString());
    var_dump($packet->getType());
    var_dump($packet->getLength());
}