<?php

defined('BASEPATH') or exit('No direct script access allowed');
/**
 * UnZip Class
 *
 * This class is based on a library I found at PHPClasses:
 * http://phpclasses.org/package/2495-PHP-Pack-and-unpack-files-packed-in-ZIP-archives.html
 *
 * The original library is a little rough around the edges so I
 * refactored it and added several additional methods -- Phil Sturgeon
 *
 * This class requires extension ZLib Enabled.
 *
 * @package CodeIgniter
 * @subpackage Libraries
 * @category Encryption
 * @author Alexandre Tedeschi
 * @author Phil Sturgeon
 * @link http://bitbucket.org/philsturgeon/codeigniter-unzip
 * @license
 *
 * @version 1.0.0
 */
class Unzip {
    private $compressed_list = array ();

    // List of files in the ZIP
    private $central_dir_list = array ();

    // Central dir list... It's a kind of 'extra attributes' for a set of files
    private $end_of_central = array ();

    // End of central dir, contains ZIP Comments
    private $info = array ();
    private $error = array ();
    private $_zip_file = '';
    private $_target_dir = FALSE;
    private $apply_chmod = 0777;
    private $fh;
    private $zip_signature = "\x50\x4b\x03\x04";

    // local file header signature
    private $dir_signature = "\x50\x4b\x01\x02";

    // central dir header signature
    private $central_signature_end = "\x50\x4b\x05\x06";

    // ignore these directories (useless meta data)
    private $_skip_dirs = array (
            '__MACOSX'
    );
    private $_allow_extensions = NULL; // What is allowed out of the zip

    // --------------------------------------------------------------------

    /**
     * Constructor
     *
     * @access Public
     * @param
     *            string
     * @return none
     */
    function __construct() {
        log_message('debug', 'Unzip Class Initialized');
    }

    // --------------------------------------------------------------------

    /**
     * Unzip all files in archive.
     *
     * @access Public
     * @param
     *            none
     * @return none
     */
    public function extract($zip_file, $target_dir = NULL, $preserve_filepath = TRUE) {
        $this->_zip_file = $zip_file;
        $this->_target_dir = $target_dir ? $target_dir : dirname($this->_zip_file);

        if (! $files = $this->_list_files()) {
            $this->set_error('ZIP folder was empty.');
            return FALSE;
        }

        $file_locations = array ();
        foreach ( $files as $file => $trash ) {
            $dirname = pathinfo($file, PATHINFO_DIRNAME);
            $extension = pathinfo($file, PATHINFO_EXTENSION);

            $folders = explode('/', $dirname);
            $out_dn = $this->_target_dir . '/' . $dirname;

            // Skip stuff in stupid folders
            if (in_array(current($folders), $this->_skip_dirs)) {
                continue;
            }

            // Skip any files that are not allowed
            if (is_array($this->_allow_extensions) and $extension and ! in_array($extension, $this->_allow_extensions)) {
                continue;
            }

            if (! is_dir($out_dn) and $preserve_filepath) {
                $str = "";
                foreach ( $folders as $folder ) {
                    $str = $str ? $str . '/' . $folder : $folder;
                    if (! is_dir($this->_target_dir . '/' . $str)) {
                        $this->set_debug('Creating folder: ' . $this->_target_dir . '/' . $str);

                        if (! @mkdir($this->_target_dir . '/' . $str)) {
                            $this->set_error('Desitnation path is not writable.');
                            return FALSE;
                        }

                        // Apply chmod if configured to do so
                        $this->apply_chmod and chmod($this->_target_dir . '/' . $str, $this->apply_chmod);
                    }
                }
            }

            if (substr($file, - 1, 1) == '/')
                continue;

            $file_locations [] = $file_location = $this->_target_dir . '/' . ($preserve_filepath ? $file : basename($file));

            $this->_extract_file($file, $file_location);
        }

        return $file_locations;
    }

    // --------------------------------------------------------------------

    /**
     * What extensions do we want out of this ZIP
     *
     * @access Public
     * @param
     *            none
     * @return none
     */
    public function allow($ext = NULL) {
        $this->_allow_extensions = $ext;
    }

    // --------------------------------------------------------------------

    /**
     * Show error messages
     *
     * @access public
     * @param
     *            string
     * @return string
     */
    public function error_string($open = '<p>', $close = '</p>') {
        return $open . implode($close . $open, $this->error) . $close;
    }

    // --------------------------------------------------------------------

    /**
     * Show debug messages
     *
     * @access public
     * @param
     *            string
     * @return string
     */
    public function debug_string($open = '<p>', $close = '</p>') {
        return $open . implode($close . $open, $this->info) . $close;
    }

    // --------------------------------------------------------------------

    /**
     * Save errors
     *
     * @access Private
     * @param
     *            string
     * @return none
     */
    function set_error($string) {
        $this->error [] = $string;
    }

    // --------------------------------------------------------------------

    /**
     * Save debug data
     *
     * @access Private
     * @param
     *            string
     * @return none
     */
    function set_debug($string) {
        $this->info [] = $string;
    }

    // --------------------------------------------------------------------

    /**
     * List all files in archive.
     *
     * @access Public
     * @param
     *            boolean
     * @return mixed
     */
    private function _list_files($stop_on_file = FALSE) {
        if (sizeof($this->compressed_list)) {
            $this->set_debug('Returning already loaded file list.');
            return $this->compressed_list;
        }

        // Open file, and set file handler
        $fh = fopen($this->_zip_file, 'r');
        $this->fh = &$fh;

        if (! $fh) {
            $this->set_error('Failed to load file: ' . $this->_zip_file);
            return FALSE;
        }

        $this->set_debug('Loading list from "End of Central Dir" index list...');

        if (! $this->_load_file_list_by_eof($fh, $stop_on_file)) {
            $this->set_debug('Failed! Trying to load list looking for signatures...');

            if (! $this->_load_files_by_signatures($fh, $stop_on_file)) {
                $this->set_debug('Failed! Could not find any valid header.');
                $this->set_error('ZIP File is corrupted or empty');

                return FALSE;
            }
        }

        return $this->compressed_list;
    }

    // --------------------------------------------------------------------

    /**
     * Unzip file in archive.
     *
     * @access Public
     * @param
     *            string, boolean
     * @return Unziped file.
     */
    private function _extract_file($compressed_file_name, $target_file_name = FALSE) {
        if (! sizeof($this->compressed_list)) {
            $this->set_debug('Trying to unzip before loading file list... Loading it!');
            $this->_list_files(FALSE, $compressed_file_name);
        }

        $fdetails = &$this->compressed_list [$compressed_file_name];

        if (! isset($this->compressed_list [$compressed_file_name])) {
            $this->set_error('File "<strong>$compressed_file_name</strong>" is not compressed in the zip.');
            return FALSE;
        }

        if (substr($compressed_file_name, - 1) == '/') {
            $this->set_error('Trying to unzip a folder name "<strong>$compressed_file_name</strong>".');
            return FALSE;
        }

        if (! $fdetails ['uncompressed_size']) {
            $this->set_debug('File "<strong>$compressed_file_name</strong>" is empty.');

            return $target_file_name ? file_put_contents($target_file_name, '') : '';
        }

        fseek($this->fh, $fdetails ['contents_start_offset']);
        $ret = $this->_uncompress(fread($this->fh, $fdetails ['compressed_size']), $fdetails ['compression_method'], $fdetails ['uncompressed_size'], $target_file_name);

        if ($this->apply_chmod and $target_file_name) {
            chmod($target_file_name, FILE_READ_MODE);
        }

        return $ret;
    }

    // --------------------------------------------------------------------

    /**
     * Free the file resource.
     *
     * @access Public
     * @param
     *            none
     * @return none
     */
    public function close() {
        // Free the file resource
        if ($this->fh) {
            fclose($this->fh);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Free the file resource Automatic destroy.
     *
     * @access Public
     * @param
     *            none
     * @return none
     */
    public function __destroy() {
        $this->close();
    }

    // --------------------------------------------------------------------

    /**
     * Uncompress file.
     * And save it to the targetFile.
     *
     * @access Private
     * @param
     *            Filecontent, int, int, boolean
     * @return none
     */
    private function _uncompress($content, $mode, $uncompressed_size, $target_file_name = FALSE) {
        switch ($mode) {
            case 0 :
                return $target_file_name ? file_put_contents($target_file_name, $content) : $content;
            case 1 :
                $this->set_error('Shrunk mode is not supported... yet?');
                return FALSE;
            case 2 :
            case 3 :
            case 4 :
            case 5 :
                $this->set_error('Compression factor ' . ($mode - 1) . ' is not supported... yet?');
                return FALSE;
            case 6 :
                $this->set_error('Implode is not supported... yet?');
                return FALSE;
            case 7 :
                $this->set_error('Tokenizing compression algorithm is not supported... yet?');
                return FALSE;
            case 8 :
                // Deflate
                return $target_file_name ? file_put_contents($target_file_name, gzinflate($content, $uncompressed_size)) : gzinflate($content, $uncompressed_size);
            case 9 :
                $this->set_error('Enhanced Deflating is not supported... yet?');
                return FALSE;
            case 10 :
                $this->set_error('PKWARE Date Compression Library Impoloding is not supported... yet?');
                return FALSE;
            case 12 :
                // Bzip2
                return $target_file_name ? file_put_contents($target_file_name, bzdecompress($content)) : bzdecompress($content);
            case 18 :
                $this->set_error('IBM TERSE is not supported... yet?');
                return FALSE;
            default :
                $this->set_error('Unknown uncompress method: $mode');
                return FALSE;
        }
    }
    private function _load_file_list_by_eof(&$fh, $stop_on_file = FALSE) {
        // Check if there's a valid Central Dir signature.
        // Let's consider a file comment smaller than 1024 characters...
        // Actually, it length can be 65536.. But we're not going to support it.
        for($x = 0; $x < 1024; $x ++) {
            fseek($fh, - 22 - $x, SEEK_END);

            $signature = fread($fh, 4);

            if ($signature == $this->central_signature_end) {
                // If found EOF Central Dir
                $eodir ['disk_number_this'] = unpack("v", fread($fh, 2)); // number of this disk
                $eodir ['disk_number'] = unpack("v", fread($fh, 2)); // number of the disk with the start of the central directory
                $eodir ['total_entries_this'] = unpack("v", fread($fh, 2)); // total number of entries in the central dir on this disk
                $eodir ['total_entries'] = unpack("v", fread($fh, 2)); // total number of entries in
                $eodir ['size_of_cd'] = unpack("V", fread($fh, 4)); // size of the central directory
                $eodir ['offset_start_cd'] = unpack("V", fread($fh, 4)); // offset of start of central directory with respect to the starting disk number
                $zip_comment_lenght = unpack("v", fread($fh, 2)); // zipfile comment length
                $eodir ['zipfile_comment'] = $zip_comment_lenght [1] ? fread($fh, $zip_comment_lenght [1]) : ''; // zipfile comment

                $this->end_of_central = array (
                        'disk_number_this' => $eodir ['disk_number_this'] [1],
                        'disk_number' => $eodir ['disk_number'] [1],
                        'total_entries_this' => $eodir ['total_entries_this'] [1],
                        'total_entries' => $eodir ['total_entries'] [1],
                        'size_of_cd' => $eodir ['size_of_cd'] [1],
                        'offset_start_cd' => $eodir ['offset_start_cd'] [1],
                        'zipfile_comment' => $eodir ['zipfile_comment']
                );

                // Then, load file list
                fseek($fh, $this->end_of_central ['offset_start_cd']);
                $signature = fread($fh, 4);

                while ( $signature == $this->dir_signature ) {
                    $dir ['version_madeby'] = unpack("v", fread($fh, 2)); // version made by
                    $dir ['version_needed'] = unpack("v", fread($fh, 2)); // version needed to extract
                    $dir ['general_bit_flag'] = unpack("v", fread($fh, 2)); // general purpose bit flag
                    $dir ['compression_method'] = unpack("v", fread($fh, 2)); // compression method
                    $dir ['lastmod_time'] = unpack("v", fread($fh, 2)); // last mod file time
                    $dir ['lastmod_date'] = unpack("v", fread($fh, 2)); // last mod file date
                    $dir ['crc-32'] = fread($fh, 4); // crc-32
                    $dir ['compressed_size'] = unpack("V", fread($fh, 4)); // compressed size
                    $dir ['uncompressed_size'] = unpack("V", fread($fh, 4)); // uncompressed size
                    $zip_file_length = unpack("v", fread($fh, 2)); // filename length
                    $extra_field_length = unpack("v", fread($fh, 2)); // extra field length
                    $fileCommentLength = unpack("v", fread($fh, 2)); // file comment length
                    $dir ['disk_number_start'] = unpack("v", fread($fh, 2)); // disk number start
                    $dir ['internal_attributes'] = unpack("v", fread($fh, 2)); // internal file attributes-byte1
                    $dir ['external_attributes1'] = unpack("v", fread($fh, 2)); // external file attributes-byte2
                    $dir ['external_attributes2'] = unpack("v", fread($fh, 2)); // external file attributes
                    $dir ['relative_offset'] = unpack("V", fread($fh, 4)); // relative offset of local header
                    $dir ['file_name'] = fread($fh, $zip_file_length [1]); // filename
                    $dir ['extra_field'] = $extra_field_length [1] ? fread($fh, $extra_field_length [1]) : ''; // extra field
                    $dir ['file_comment'] = $fileCommentLength [1] ? fread($fh, $fileCommentLength [1]) : ''; // file comment

                    // Convert the date and time, from MS-DOS format to UNIX Timestamp
                    $binary_mod_date = str_pad(decbin($dir ['lastmod_date'] [1]), 16, '0', STR_PAD_LEFT);
                    $binary_mod_time = str_pad(decbin($dir ['lastmod_time'] [1]), 16, '0', STR_PAD_LEFT);
                    $last_mod_year = bindec(substr($binary_mod_date, 0, 7)) + 1980;
                    $last_mod_month = bindec(substr($binary_mod_date, 7, 4));
                    $last_mod_day = bindec(substr($binary_mod_date, 11, 5));
                    $last_mod_hour = bindec(substr($binary_mod_time, 0, 5));
                    $last_mod_minute = bindec(substr($binary_mod_time, 5, 6));
                    $last_mod_second = bindec(substr($binary_mod_time, 11, 5));

                    $this->central_dir_list [$dir ['file_name']] = array (
                            'version_madeby' => $dir ['version_madeby'] [1],
                            'version_needed' => $dir ['version_needed'] [1],
                            'general_bit_flag' => str_pad(decbin($dir ['general_bit_flag'] [1]), 8, '0', STR_PAD_LEFT),
                            'compression_method' => $dir ['compression_method'] [1],
                            'lastmod_datetime' => mktime($last_mod_hour, $last_mod_minute, $last_mod_second, $last_mod_month, $last_mod_day, $last_mod_year),
                            'crc-32' => str_pad(dechex(ord($dir ['crc-32'] [3])), 2, '0', STR_PAD_LEFT) . str_pad(dechex(ord($dir ['crc-32'] [2])), 2, '0', STR_PAD_LEFT) . str_pad(dechex(ord($dir ['crc-32'] [1])), 2, '0', STR_PAD_LEFT) . str_pad(dechex(ord($dir ['crc-32'] [0])), 2, '0', STR_PAD_LEFT),
                            'compressed_size' => $dir ['compressed_size'] [1],
                            'uncompressed_size' => $dir ['uncompressed_size'] [1],
                            'disk_number_start' => $dir ['disk_number_start'] [1],
                            'internal_attributes' => $dir ['internal_attributes'] [1],
                            'external_attributes1' => $dir ['external_attributes1'] [1],
                            'external_attributes2' => $dir ['external_attributes2'] [1],
                            'relative_offset' => $dir ['relative_offset'] [1],
                            'file_name' => $dir ['file_name'],
                            'extra_field' => $dir ['extra_field'],
                            'file_comment' => $dir ['file_comment']
                    );

                    $signature = fread($fh, 4);
                }

                // If loaded centralDirs, then try to identify the offsetPosition of the compressed data.
                if ($this->central_dir_list) {
                    foreach ( $this->central_dir_list as $filename => $details ) {
                        $i = $this->_get_file_header($fh, $details ['relative_offset']);

                        $this->compressed_list [$filename] ['file_name'] = $filename;
                        $this->compressed_list [$filename] ['compression_method'] = $details ['compression_method'];
                        $this->compressed_list [$filename] ['version_needed'] = $details ['version_needed'];
                        $this->compressed_list [$filename] ['lastmod_datetime'] = $details ['lastmod_datetime'];
                        $this->compressed_list [$filename] ['crc-32'] = $details ['crc-32'];
                        $this->compressed_list [$filename] ['compressed_size'] = $details ['compressed_size'];
                        $this->compressed_list [$filename] ['uncompressed_size'] = $details ['uncompressed_size'];
                        $this->compressed_list [$filename] ['lastmod_datetime'] = $details ['lastmod_datetime'];
                        $this->compressed_list [$filename] ['extra_field'] = $i ['extra_field'];
                        $this->compressed_list [$filename] ['contents_start_offset'] = $i ['contents_start_offset'];

                        if (strtolower($stop_on_file) == strtolower($filename)) {
                            break;
                        }
                    }
                }

                return TRUE;
            }
        }
        return FALSE;
    }
    private function _load_files_by_signatures(&$fh, $stop_on_file = FALSE) {
        fseek($fh, 0);

        $return = FALSE;
        for(;;) {
            $details = $this->_get_file_header($fh);

            if (! $details) {
                $this->set_debug('Invalid signature. Trying to verify if is old style Data Descriptor...');
                fseek($fh, 12 - 4, SEEK_CUR); // 12: Data descriptor - 4: Signature (that will be read again)
                $details = $this->_get_file_header($fh);
            }

            if (! $details) {
                $this->set_debug('Still invalid signature. Probably reached the end of the file.');
                break;
            }

            $filename = $details ['file_name'];
            $this->compressed_list [$filename] = $details;
            $return = true;

            if (strtolower($stop_on_file) == strtolower($filename)) {
                break;
            }
        }

        return $return;
    }
    private function _get_file_header(&$fh, $start_offset = FALSE) {
        if ($start_offset !== FALSE) {
            fseek($fh, $start_offset);
        }

        $signature = fread($fh, 4);

        if ($signature == $this->zip_signature) {
            // Get information about the zipped file
            $file ['version_needed'] = unpack("v", fread($fh, 2)); // version needed to extract
            $file ['general_bit_flag'] = unpack("v", fread($fh, 2)); // general purpose bit flag
            $file ['compression_method'] = unpack("v", fread($fh, 2)); // compression method
            $file ['lastmod_time'] = unpack("v", fread($fh, 2)); // last mod file time
            $file ['lastmod_date'] = unpack("v", fread($fh, 2)); // last mod file date
            $file ['crc-32'] = fread($fh, 4); // crc-32
            $file ['compressed_size'] = unpack("V", fread($fh, 4)); // compressed size
            $file ['uncompressed_size'] = unpack("V", fread($fh, 4)); // uncompressed size
            $zip_file_length = unpack("v", fread($fh, 2)); // filename length
            $extra_field_length = unpack("v", fread($fh, 2)); // extra field length
            $file ['file_name'] = fread($fh, $zip_file_length [1]); // filename
            $file ['extra_field'] = $extra_field_length [1] ? fread($fh, $extra_field_length [1]) : ''; // extra field
            $file ['contents_start_offset'] = ftell($fh);

            // Bypass the whole compressed contents, and look for the next file
            fseek($fh, $file ['compressed_size'] [1], SEEK_CUR);

            // Convert the date and time, from MS-DOS format to UNIX Timestamp
            $binary_mod_date = str_pad(decbin($file ['lastmod_date'] [1]), 16, '0', STR_PAD_LEFT);
            $binary_mod_time = str_pad(decbin($file ['lastmod_time'] [1]), 16, '0', STR_PAD_LEFT);

            $last_mod_year = bindec(substr($binary_mod_date, 0, 7)) + 1980;
            $last_mod_month = bindec(substr($binary_mod_date, 7, 4));
            $last_mod_day = bindec(substr($binary_mod_date, 11, 5));
            $last_mod_hour = bindec(substr($binary_mod_time, 0, 5));
            $last_mod_minute = bindec(substr($binary_mod_time, 5, 6));
            $last_mod_second = bindec(substr($binary_mod_time, 11, 5));

            // Mount file table
            $i = array (
                    'file_name' => $file ['file_name'],
                    'compression_method' => $file ['compression_method'] [1],
                    'version_needed' => $file ['version_needed'] [1],
                    'lastmod_datetime' => mktime($last_mod_hour, $last_mod_minute, $last_mod_second, $last_mod_month, $last_mod_day, $last_mod_year),
                    'crc-32' => str_pad(dechex(ord($file ['crc-32'] [3])), 2, '0', STR_PAD_LEFT) . str_pad(dechex(ord($file ['crc-32'] [2])), 2, '0', STR_PAD_LEFT) . str_pad(dechex(ord($file ['crc-32'] [1])), 2, '0', STR_PAD_LEFT) . str_pad(dechex(ord($file ['crc-32'] [0])), 2, '0', STR_PAD_LEFT),
                    'compressed_size' => $file ['compressed_size'] [1],
                    'uncompressed_size' => $file ['uncompressed_size'] [1],
                    'extra_field' => $file ['extra_field'],
                    'general_bit_flag' => str_pad(decbin($file ['general_bit_flag'] [1]), 8, '0', STR_PAD_LEFT),
                    'contents_start_offset' => $file ['contents_start_offset']
            );

            return $i;
        }

        return FALSE;
    }
}

/* End of file Unzip.php */
/* Location: ./system/libraries/Unzip.php */