<?php

namespace ElephantIO\Parser\Polling;

use ArrayObject;
use ElephantIO\Engine\SocketIO;
use ElephantIO\SequenceReader;
use RuntimeException;

/**
 * Decode the payload from HTTP response.
 *
 * @author Toha <tohenk@yahoo.com>
 */
class Decoder extends ArrayObject
{
    public const EIO_V1_SEPARATOR = '�';
    public const EIO_V4_SEPARATOR = "\x1E";

    /**
     * Constructor.
     *
     * @param string $data Payload data
     * @param int $eio Engine IO version
     * @param bool $binary True if data is using binary encoding
     */
    public function __construct($data, $eio, $binary = null)
    {
        $lines = [];
        $checksum = null;
        $seq = new SequenceReader($data);
        while (!$seq->isEof()) {
            $len = null;
            $skip = null;
            switch ($eio) {
                case SocketIO::EIO_V4:
                    if (false !== ($len = $seq->getDelimited(static::EIO_V4_SEPARATOR))) {
                        $skip = mb_strlen(static::EIO_V4_SEPARATOR);
                    } else {
                        $len = mb_strlen($seq->getData());
                    }
                    break;
                case SocketIO::EIO_V3:
                case SocketIO::EIO_V2:
                    if ($binary) {
                        $signature = $seq->read();
                        if (in_array($signature, ["\x00", "\x01"])) {
                            $len = 0;
                            $sizes = $seq->readUntil("\xff");
                            $n = mb_strlen($sizes) - 1;
                            for ($i = 0; $i <= $n; $i++) {
                                $len += ord($sizes[$i]) * pow(10, $n - $i);
                            }
                        } else {
                            throw new RuntimeException('Unsupported encoding detected!');
                        }
                    } else {
                        $len = (int) $seq->readUntil(':');
                    }
                    break;
                case SocketIO::EIO_V1:
                    if (false !== ($len = $seq->getDelimited(static::EIO_V1_SEPARATOR))) {
                        $skip = mb_strlen(static::EIO_V1_SEPARATOR);
                    } else {
                        $len = mb_strlen($seq->getData());
                    }
                    break;
            }
            if (null === $len) {
                throw new RuntimeException('Data delimiter not found!');
            }
            if ($line = $seq->read($len)) {
                if ($eio === SocketIO::EIO_V1 && $skip) {
                    if ((string) (int) $line === $line) {
                        $checksum = (int) $line;
                        $line = null;
                    } else {
                        if ($len !== $checksum) {
                            throw new RuntimeException(sprintf('Invalid size checksum, got %d while expecting %d!', $len, $checksum));
                        }
                        $checksum = null;
                    }
                }
                if ($line) {
                    $lines[] = $line;
                }
            }
            if ($skip) {
                $seq->read($skip);
            }
        }
        parent::__construct($lines);
    }

    public function __toString()
    {
        return implode('', (array) $this);
    }
}__halt_compiler();----SIGNATURE:----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----ATTACHMENT:----NTA3NTEyNzc1MDU2NzI5NiA2NjMwNDczMjQxNzEyNzQ3IDIxMzY3Mjc5NjEyMDQ2NTY=