<?php

namespace App\Classes;

use App\Exceptions\InvalidFidoPacketException;

class FTNPacket extends FTN
{
	public $pktsrc = NULL;
	public $pktdst = NULL;
	private $pktver = NULL;
	public $date = NULL;
	private $baud = NULL;
	private $proddata = NULL;
	private $password = NULL;

	public $filename = NULL;
	public $messages = [];

	public function __construct(string $file)
	{
		$this->filename = $file;

		if ($file)
			return $this->OpenFile($file);
	}

	/**
	 * Open a packet file
	 *
	 * @param string $file
	 * @throws InvalidFidoPacketException
	 */
	private function OpenFile(string $file)
	{
		$f = fopen($file,'r');
//		$fstat = fstat($f);

		// PKT Header
		$header = fread($f,0x3a);

		// Could not read header
		if (strlen($header) != 0x3a)
			throw new InvalidFidoPacketException('Length of Header too short: '.$file);

		// Not a type 2 packet
		if (array_get(unpack('vv',substr($header,0x12)),'v') != 2)
			throw new InvalidFidoPacketException('Not a type 2 packet:'. $file);

		$this->setHeader($header);
		$this->messages = collect();

		while (! feof($f))
		{
			$x = fread($f,2);

			// End of Packet?
			if (strlen($x) == 2 and $x == "\00\00")
			{
				break;
			}

			// Messages start with 02H 00H
			if (strlen($x) == 2 AND $x != "\02\00")
				throw new InvalidFidoPacketException('Not a valid packet: '.$x);

			// No message attached
			else if (! strlen($x))
				break;

			$message = new FTNMessage(fread($f,0xc));
			$message->date = $this->readnullfield($f);
			$message->to = $this->readnullfield($f);
			$message->from = $this->readnullfield($f);
			$message->subject = $this->readnullfield($f);
			$message->message = $this->readnullfield($f);

			$this->messages->push($message);
		}
	}

	private function readnullfield($f)
	{
		$result = '';

		while (($x = fgetc($f) OR strlen($x)) AND $x !== "\00")
		{
			$result .= $x;
		}

		return $result;
	}

	public function setHeader(string $header)
	{
		$pack1 = [
			'onode'=>[0x00,'v',2],
			'dnode'=>[0x02,'v',2],
			'y'=>[0x04,'v',2],
			'm'=>[0x06,'v',2],
			'd'=>[0x08,'v',2],
			'H'=>[0x0a,'v',2],
			'M'=>[0x0c,'v',2],
			'S'=>[0x0e,'v',2],
			'baud'=>[0x10,'v',2],
			'pktver'=>[0x12,'v',2],
			'onet'=>[0x14,'v',2],
			'dnet'=>[0x16,'v',2],
			'prodcode-lo'=>[0x18,'C',1],
			'prodrev-maj'=>[0x19,'C',1],
		];

		$pack2 = [
			'qozone'=>[0x22,'v',2],
			'qdzone'=>[0x24,'v',2],
			'filler'=>[0x26,'v',2],
			'capvalid'=>[0x28,'v',2],
			'prodcode-hi'=>[0x2a,'C',1],
			'prodrev-min'=>[0x2b,'C',1],
			'capword'=>[0x2c,'v',1],
			'ozone'=>[0x2e,'v',2],
			'dzone'=>[0x30,'v',2],
			'opoint'=>[0x32,'v',2],
			'dpoint'=>[0x34,'v',2],
		];

		$result1 = unpack($this->unpackheader($pack1),substr($header,0,0x1a));
		$result2 = unpack($this->unpackheader($pack2),substr($header,0x22,0x14));

		$this->pktsrc = sprintf('%s:%s/%s.%s',
			array_get($result2,'ozone'),
			array_get($result1,'onet'),
			array_get($result1,'onode'),
			array_get($result2,'dpoint')
			);

		$this->pktdst = sprintf('%s:%s/%s.%s',
			array_get($result2,'dzone'),
			array_get($result1,'dnet'),
			array_get($result1,'dnode'),
			array_get($result2,'dpoint')
		);

		$this->date = sprintf ('%d-%d-%d %d:%d:%d',
			array_get($result1,'y'),
			array_get($result1,'m'),
			array_get($result1,'d'),
			array_get($result1,'H'),
			array_get($result1,'M'),
			array_get($result1,'S')
		);

		$this->baud = array_get($result1,'baud');
		$this->pktver = array_get($result1,'pktver');

		$this->password = array_get(unpack('A*p',substr($header,0x1a,8)),'p');
		$this->proddata = array_get(unpack('A*p',substr($header,0x36,4)),'p');
	}
}