<?php

declare(strict_types=1);

/**
 * @author Pavel Djundik
 *
 * @link https://xpaw.me
 * @link https://github.com/xPaw/PHP-Source-Query
 *
 * @license GNU Lesser General Public License, version 2.1
 *
 * @internal
 */

namespace xPaw\SourceQuery;

use xPaw\SourceQuery\Exception\AuthenticationException;
use xPaw\SourceQuery\Exception\InvalidPacketException;

/**
 * Class GoldSourceRcon
 *
 * @package xPaw\SourceQuery
 *
 * @uses AuthenticationException
 * @uses InvalidPacketException
 */
final class GoldSourceRcon
{
    /**
     * Points to socket class
     *
     * @var BaseSocket
     */
    private $Socket;

    private string $RconPassword = '';
    private string $RconChallenge = '';

    public function __construct(BaseSocket $Socket)
    {
        $this->Socket = $Socket;
    }

    public function Close(): void
    {
        $this->RconChallenge = '';
        $this->RconPassword  = '';
    }

    public function Open(): void
    {
        //
    }

    public function Write(int $Header, string $String = ''): bool
    {
        $Command = pack('cccca*', 0xFF, 0xFF, 0xFF, 0xFF, $String);
        $Length  = strlen($Command);

        return $Length === fwrite($this->Socket->Socket, $Command, $Length);
    }

    /**
     * @param int $Length
     * @throws AuthenticationException
     * @return Buffer
     */
    public function Read(int $Length = 1400): Buffer
    {
        // GoldSource RCON has same structure as Query
        $Buffer = $this->Socket->Read();

        $StringBuffer = '';
        $ReadMore = false;

        // There is no indentifier of the end, so we just need to continue reading
        do {
            $ReadMore = $Buffer->Remaining() > 0;

            if ($ReadMore) {
                if ($Buffer->GetByte() !== SourceQuery::S2A_RCON) {
                    throw new InvalidPacketException('Invalid rcon response.', InvalidPacketException::PACKET_HEADER_MISMATCH);
                }

                $Packet = $Buffer->Get();
                $StringBuffer .= $Packet;
                //$StringBuffer .= SubStr( $Packet, 0, -2 );

                // Let's assume if this packet is not long enough, there are no more after this one
                $ReadMore = strlen($Packet) > 1000; // use 1300?

                if ($ReadMore) {
                    $Buffer = $this->Socket->Read();
                }
            }
        } while ($ReadMore);

        $Trimmed = trim($StringBuffer);

        if ($Trimmed === 'Bad rcon_password.') {
            throw new AuthenticationException($Trimmed, AuthenticationException::BAD_PASSWORD);
        } elseif ($Trimmed === 'You have been banned from this server.') {
            throw new AuthenticationException($Trimmed, AuthenticationException::BANNED);
        }

        $Buffer->Set($Trimmed);

        return $Buffer;
    }

    public function Command(string $Command): string
    {
        if (!$this->RconChallenge) {
            throw new AuthenticationException('Tried to execute a RCON command before successful authorization.', AuthenticationException::BAD_PASSWORD);
        }

        $this->Write(0, 'rcon ' . $this->RconChallenge . ' "' . $this->RconPassword . '" ' . $Command . "\0");
        $Buffer = $this->Read();

        return $Buffer->Get();
    }

    public function Authorize(string $Password): void
    {
        $this->RconPassword = $Password;

        $this->Write(0, 'challenge rcon');
        $Buffer = $this->Socket->Read();

        if ($Buffer->Get(14) !== 'challenge rcon') {
            throw new AuthenticationException('Failed to get RCON challenge.', AuthenticationException::BAD_PASSWORD);
        }

        $this->RconChallenge = trim($Buffer->Get());
    }
}