<?php

declare(strict_types=1);

namespace ZipStream;

use HashContext;
use Psr\Http\Message\StreamInterface;
use ZipStream\Exception\FileNotFoundException;
use ZipStream\Exception\FileNotReadableException;
use ZipStream\Exception\OverflowException;
use ZipStream\Option\File as FileOptions;
use ZipStream\Option\Method;
use ZipStream\Option\Version;

class File
{
    public const HASH_ALGORITHM = 'crc32b';

    public const BIT_ZERO_HEADER = 0x0008;

    public const BIT_EFS_UTF8 = 0x0800;

    public const COMPUTE = 1;

    public const SEND = 2;

    private const CHUNKED_READ_BLOCK_SIZE = 1048576;

    /**
     * @var string
     */
    public $name;

    /**
     * @var FileOptions
     */
    public $opt;

    /**
     * @var Bigint
     */
    public $len;

    /**
     * @var Bigint
     */
    public $zlen;

    /** @var  int */
    public $crc;

    /**
     * @var Bigint
     */
    public $hlen;

    /**
     * @var Bigint
     */
    public $ofs;

    /**
     * @var int
     */
    public $bits;

    /**
     * @var Version
     */
    public $version;

    /**
     * @var ZipStream
     */
    public $zip;

    /**
     * @var resource
     */
    private $deflate;

    /**
     * @var HashContext
     */
    private $hash;

    /**
     * @var Method
     */
    private $method;

    /**
     * @var Bigint
     */
    private $totalLength;

    public function __construct(ZipStream $zip, string $name, ?FileOptions $opt = null)
    {
        $this->zip = $zip;

        $this->name = $name;
        $this->opt = $opt ?: new FileOptions();
        $this->method = $this->opt->getMethod();
        $this->version = Version::STORE();
        $this->ofs = new Bigint();
    }

    public function processPath(string $path): void
    {
        if (!is_readable($path)) {
            if (!file_exists($path)) {
                throw new FileNotFoundException($path);
            }
            throw new FileNotReadableException($path);
        }
        if ($this->zip->isLargeFile($path) === false) {
            $data = file_get_contents($path);
            $this->processData($data);
        } else {
            $this->method = $this->zip->opt->getLargeFileMethod();

            $stream = new Stream(fopen($path, 'rb'));
            $this->processStream($stream);
            $stream->close();
        }
    }

    public function processData(string $data): void
    {
        $this->len = new Bigint(strlen($data));
        $this->crc = crc32($data);

        // compress data if needed
        if ($this->method->equals(Method::DEFLATE())) {
            $data = gzdeflate($data);
        }

        $this->zlen = new Bigint(strlen($data));
        $this->addFileHeader();
        $this->zip->send($data);
        $this->addFileFooter();
    }

    /**
     * Create and send zip header for this file.
     *
     * @return void
     * @throws \ZipStream\Exception\EncodingException
     */
    public function addFileHeader(): void
    {
        $name = static::filterFilename($this->name);

        // calculate name length
        $nameLength = strlen($name);

        // create dos timestamp
        $time = static::dosTime($this->opt->getTime()->getTimestamp());

        $comment = $this->opt->getComment();

        if (!mb_check_encoding($name, 'ASCII') ||
            !mb_check_encoding($comment, 'ASCII')) {
            // Sets Bit 11: Language encoding flag (EFS).  If this bit is set,
            // the filename and comment fields for this file
            // MUST be encoded using UTF-8. (see APPENDIX D)
            if (mb_check_encoding($name, 'UTF-8') &&
                mb_check_encoding($comment, 'UTF-8')) {
                $this->bits |= self::BIT_EFS_UTF8;
            }
        }

        if ($this->method->equals(Method::DEFLATE())) {
            $this->version = Version::DEFLATE();
        }

        $force = (bool)($this->bits & self::BIT_ZERO_HEADER) &&
            $this->zip->opt->isEnableZip64();

        $footer = $this->buildZip64ExtraBlock($force);

        // If this file will start over 4GB limit in ZIP file,
        // CDR record will have to use Zip64 extension to describe offset
        // to keep consistency we use the same value here
        if ($this->zip->ofs->isOver32()) {
            $this->version = Version::ZIP64();
        }

        $fields = [
            ['V', ZipStream::FILE_HEADER_SIGNATURE],
            ['v', $this->version->getValue()],      // Version needed to Extract
            ['v', $this->bits],                     // General purpose bit flags - data descriptor flag set
            ['v', $this->method->getValue()],       // Compression method
            ['V', $time],                           // Timestamp (DOS Format)
            ['V', $this->crc],                      // CRC32 of data (0 -> moved to data descriptor footer)
            ['V', $this->zlen->getLowFF($force)],   // Length of compressed data (forced to 0xFFFFFFFF for zero header)
            ['V', $this->len->getLowFF($force)],    // Length of original data (forced to 0xFFFFFFFF for zero header)
            ['v', $nameLength],                     // Length of filename
            ['v', strlen($footer)],                 // Extra data (see above)
        ];

        // pack fields and calculate "total" length
        $header = ZipStream::packFields($fields);

        // print header and filename
        $data = $header . $name . $footer;
        $this->zip->send($data);

        // save header length
        $this->hlen = Bigint::init(strlen($data));
    }

    /**
     * Strip characters that are not legal in Windows filenames
     * to prevent compatibility issues
     *
     * @param string $filename Unprocessed filename
     * @return string
     */
    public static function filterFilename(string $filename): string
    {
        // strip leading slashes from file name
        // (fixes bug in windows archive viewer)
        $filename = preg_replace('/^\\/+/', '', $filename);

        return str_replace(['\\', ':', '*', '?', '"', '<', '>', '|'], '_', $filename);
    }

    /**
     * Create and send data descriptor footer for this file.
     *
     * @return void
     */
    public function addFileFooter(): void
    {
        if ($this->bits & self::BIT_ZERO_HEADER) {
            // compressed and uncompressed size
            $sizeFormat = 'V';
            if ($this->zip->opt->isEnableZip64()) {
                $sizeFormat = 'P';
            }
            $fields = [
                ['V', ZipStream::DATA_DESCRIPTOR_SIGNATURE],
                ['V', $this->crc],              // CRC32
                [$sizeFormat, $this->zlen],     // Length of compressed data
                [$sizeFormat, $this->len],      // Length of original data
            ];

            $footer = ZipStream::packFields($fields);
            $this->zip->send($footer);
        } else {
            $footer = '';
        }
        $this->totalLength = $this->hlen->add($this->zlen)->add(Bigint::init(strlen($footer)));
        $this->zip->addToCdr($this);
    }

    public function processStream(StreamInterface $stream): void
    {
        $this->zlen = new Bigint();
        $this->len = new Bigint();

        if ($this->zip->opt->isZeroHeader()) {
            $this->processStreamWithZeroHeader($stream);
        } else {
            $this->processStreamWithComputedHeader($stream);
        }
    }

    /**
     * Send CDR record for specified file.
     *
     * @return string
     */
    public function getCdrFile(): string
    {
        $name = static::filterFilename($this->name);

        // get attributes
        $comment = $this->opt->getComment();

        // get dos timestamp
        $time = static::dosTime($this->opt->getTime()->getTimestamp());

        $footer = $this->buildZip64ExtraBlock();

        $fields = [
            ['V', ZipStream::CDR_FILE_SIGNATURE],   // Central file header signature
            ['v', ZipStream::ZIP_VERSION_MADE_BY],  // Made by version
            ['v', $this->version->getValue()],      // Extract by version
            ['v', $this->bits],                     // General purpose bit flags - data descriptor flag set
            ['v', $this->method->getValue()],       // Compression method
            ['V', $time],                           // Timestamp (DOS Format)
            ['V', $this->crc],                      // CRC32
            ['V', $this->zlen->getLowFF()],         // Compressed Data Length
            ['V', $this->len->getLowFF()],          // Original Data Length
            ['v', strlen($name)],                   // Length of filename
            ['v', strlen($footer)],                 // Extra data len (see above)
            ['v', strlen($comment)],                // Length of comment
            ['v', 0],                               // Disk number
            ['v', 0],                               // Internal File Attributes
            ['V', 32],                              // External File Attributes
            ['V', $this->ofs->getLowFF()],           // Relative offset of local header
        ];

        // pack fields, then append name and comment
        $header = ZipStream::packFields($fields);

        return $header . $name . $footer . $comment;
    }

    /**
     * @return Bigint
     */
    public function getTotalLength(): Bigint
    {
        return $this->totalLength;
    }

    /**
     * Convert a UNIX timestamp to a DOS timestamp.
     *
     * @param int $when
     * @return int DOS Timestamp
     */
    final protected static function dosTime(int $when): int
    {
        // get date array for timestamp
        $d = getdate($when);

        // set lower-bound on dates
        if ($d['year'] < 1980) {
            $d = [
                'year' => 1980,
                'mon' => 1,
                'mday' => 1,
                'hours' => 0,
                'minutes' => 0,
                'seconds' => 0,
            ];
        }

        // remove extra years from 1980
        $d['year'] -= 1980;

        // return date string
        return
            ($d['year'] << 25) |
            ($d['mon'] << 21) |
            ($d['mday'] << 16) |
            ($d['hours'] << 11) |
            ($d['minutes'] << 5) |
            ($d['seconds'] >> 1);
    }

    protected function buildZip64ExtraBlock(bool $force = false): string
    {
        $fields = [];
        if ($this->len->isOver32($force)) {
            $fields[] = ['P', $this->len];          // Length of original data
        }

        if ($this->len->isOver32($force)) {
            $fields[] = ['P', $this->zlen];         // Length of compressed data
        }

        if ($this->ofs->isOver32()) {
            $fields[] = ['P', $this->ofs];          // Offset of local header record
        }

        if (!empty($fields)) {
            if (!$this->zip->opt->isEnableZip64()) {
                throw new OverflowException();
            }

            array_unshift(
                $fields,
                ['v', 0x0001],                      // 64 bit extension
                ['v', count($fields) * 8]             // Length of data block
            );
            $this->version = Version::ZIP64();
        }

        if ($this->bits & self::BIT_EFS_UTF8) {
            // Put the tricky entry to
            // force Linux unzip to lookup EFS flag.
            $fields[] = ['v', 0x5653];  // Choose 'ZS' for proprietary usage
            $fields[] = ['v', 0x0000];  // zero length
        }

        return ZipStream::packFields($fields);
    }

    protected function processStreamWithZeroHeader(StreamInterface $stream): void
    {
        $this->bits |= self::BIT_ZERO_HEADER;
        $this->addFileHeader();
        $this->readStream($stream, self::COMPUTE | self::SEND);
        $this->addFileFooter();
    }

    protected function readStream(StreamInterface $stream, ?int $options = null): void
    {
        $this->deflateInit();
        $total = 0;
        $size = $this->opt->getSize();
        while (!$stream->eof() && ($size === 0 || $total < $size)) {
            $data = $stream->read(self::CHUNKED_READ_BLOCK_SIZE);
            $total += strlen($data);
            if ($size > 0 && $total > $size) {
                $data = substr($data, 0, strlen($data)-($total - $size));
            }
            $this->deflateData($stream, $data, $options);
            if ($options & self::SEND) {
                $this->zip->send($data);
            }
        }
        $this->deflateFinish($options);
    }

    protected function deflateInit(): void
    {
        $hash = hash_init(self::HASH_ALGORITHM);
        $this->hash = $hash;
        if ($this->method->equals(Method::DEFLATE())) {
            $this->deflate = deflate_init(
                ZLIB_ENCODING_RAW,
                ['level' => $this->opt->getDeflateLevel()]
            );
        }
    }

    protected function deflateData(StreamInterface $stream, string &$data, ?int $options = null): void
    {
        if ($options & self::COMPUTE) {
            $this->len = $this->len->add(Bigint::init(strlen($data)));
            hash_update($this->hash, $data);
        }
        if ($this->deflate) {
            $data = deflate_add(
                $this->deflate,
                $data,
                $stream->eof()
                    ? ZLIB_FINISH
                    : ZLIB_NO_FLUSH
            );
        }
        if ($options & self::COMPUTE) {
            $this->zlen = $this->zlen->add(Bigint::init(strlen($data)));
        }
    }

    protected function deflateFinish(?int $options = null): void
    {
        if ($options & self::COMPUTE) {
            $this->crc = hexdec(hash_final($this->hash));
        }
    }

    protected function processStreamWithComputedHeader(StreamInterface $stream): void
    {
        $this->readStream($stream, self::COMPUTE);
        $stream->rewind();

        $this->addFileHeader();
        $this->readStream($stream, self::SEND);
        $this->addFileFooter();
    }
}

• [D] Exception
• [D] Option
• [F] Bigint.php
  Delete
• [F] DeflateStream.php
  Delete
• [F] Exception.php
  Delete
• [F] File.php
  Delete
• [F] Stream.php
  Delete
• [F] ZipStream.php
  Delete

About Section

About NFC Pay: Our Story and Mission

NFC Pay was founded with a vision to transform the way people handle transactions. Our journey is defined by a commitment to innovation, security, and convenience. We strive to deliver seamless, user-friendly payment solutions that make everyday transactions effortless and secure. Our mission is to empower you to pay with ease and confidence, anytime, anywhere.

• Simplifying Payments, One Tap at a Time.
• Reinventing Your Wallet for Modern Convenience.
• Smart Payments for a Effortless Lifestyle.
• Experience the Ease of Tap and Pay.
• Innovative Solutions for Your Daily Transactions.

FAQ Section

Frequently Asked Questions About NFC Pay

Here are answers to some common questions about NFC Pay. We aim to provide clear and concise information to help you understand how our platform works and how it can benefit you. If you have any further inquiries, please don’t hesitate to contact our support team.

How do I register for NFC Pay?

Download the app and sign up using your email or phone number, then complete the verification process.

Is my payment information secure?

Yes, we use advanced encryption and security protocols to protect your payment details.

Can I add multiple cards to my NFC Pay wallet?

Absolutely, you can link multiple debit or credit cards to your wallet.

How do I transfer money to another user?

Go to the transfer section, select the recipient, enter the amount, and authorize the transfer.

What should I do if I forget my PIN?

Use the “Forgot PIN” feature in the app to reset it following the provided instructions.

How can I activate my merchant account?

Sign up for a merchant account through the app and follow the setup instructions to start accepting payments.

Can I track my payment status?

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