<?php
/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at http://getid3.sourceforge.net                 //
//            or http://www.getid3.org                         //
//          also https://github.com/JamesHeinrich/getID3       //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details                             //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.archive.zip.php                                      //
// module for analyzing pkZip files                            //
// dependencies: NONE                                          //
//                                                            ///
/////////////////////////////////////////////////////////////////


class getid3_zip extends getid3_handler
{

    public function 
Analyze() {
        
$info = &$this->getid3->info;

        
$info['fileformat']      = 'zip';
        
$info['zip']['encoding'] = 'ISO-8859-1';
        
$info['zip']['files']    = array();

        
$info['zip']['compressed_size']   = 0;
        
$info['zip']['uncompressed_size'] = 0;
        
$info['zip']['entries_count']     = 0;

        if (!
getid3_lib::intValueSupported($info['filesize'])) {
            
$info['error'][] = 'File is larger than '.round(PHP_INT_MAX 1073741824).'GB, not supported by PHP';
            return 
false;
        } else {
            
$EOCDsearchData    '';
            
$EOCDsearchCounter 0;
            while (
$EOCDsearchCounter++ < 512) {

                
$this->fseek(-128 $EOCDsearchCounterSEEK_END);
                
$EOCDsearchData $this->fread(128).$EOCDsearchData;

                if (
strstr($EOCDsearchData'PK'."\x05\x06")) {

                    
$EOCDposition strpos($EOCDsearchData'PK'."\x05\x06");
                    
$this->fseek((-128 $EOCDsearchCounter) + $EOCDpositionSEEK_END);
                    
$info['zip']['end_central_directory'] = $this->ZIPparseEndOfCentralDirectory();

                    
$this->fseek($info['zip']['end_central_directory']['directory_offset']);
                    
$info['zip']['entries_count'] = 0;
                    while (
$centraldirectoryentry $this->ZIPparseCentralDirectory($this->getid3->fp)) {
                        
$info['zip']['central_directory'][] = $centraldirectoryentry;
                        
$info['zip']['entries_count']++;
                        
$info['zip']['compressed_size']   += $centraldirectoryentry['compressed_size'];
                        
$info['zip']['uncompressed_size'] += $centraldirectoryentry['uncompressed_size'];

                        
//if ($centraldirectoryentry['uncompressed_size'] > 0) { zero-byte files are valid
                        
if (!empty($centraldirectoryentry['filename'])) {
                            
$info['zip']['files'] = getid3_lib::array_merge_clobber($info['zip']['files'], getid3_lib::CreateDeepArray($centraldirectoryentry['filename'], '/'$centraldirectoryentry['uncompressed_size']));
                        }
                    }

                    if (
$info['zip']['entries_count'] == 0) {
                        
$info['error'][] = 'No Central Directory entries found (truncated file?)';
                        return 
false;
                    }

                    if (!empty(
$info['zip']['end_central_directory']['comment'])) {
                        
$info['zip']['comments']['comment'][] = $info['zip']['end_central_directory']['comment'];
                    }

                    if (isset(
$info['zip']['central_directory'][0]['compression_method'])) {
                        
$info['zip']['compression_method'] = $info['zip']['central_directory'][0]['compression_method'];
                    }
                    if (isset(
$info['zip']['central_directory'][0]['flags']['compression_speed'])) {
                        
$info['zip']['compression_speed']  = $info['zip']['central_directory'][0]['flags']['compression_speed'];
                    }
                    if (isset(
$info['zip']['compression_method']) && ($info['zip']['compression_method'] == 'store') && !isset($info['zip']['compression_speed'])) {
                        
$info['zip']['compression_speed']  = 'store';
                    }

                    
// secondary check - we (should) already have all the info we NEED from the Central Directory above, but scanning each
                    // Local File Header entry will
                    
foreach ($info['zip']['central_directory'] as $central_directory_entry) {
                        
$this->fseek($central_directory_entry['entry_offset']);
                        if (
$fileentry $this->ZIPparseLocalFileHeader()) {
                            
$info['zip']['entries'][] = $fileentry;
                        } else {
                            
$info['warning'][] = 'Error parsing Local File Header at offset '.$central_directory_entry['entry_offset'];
                        }
                    }

                    if (!empty(
$info['zip']['files']['[Content_Types].xml']) &&
                        !empty(
$info['zip']['files']['_rels']['.rels'])      &&
                        !empty(
$info['zip']['files']['docProps']['app.xml']) &&
                        !empty(
$info['zip']['files']['docProps']['core.xml'])) {
                           
// http://technet.microsoft.com/en-us/library/cc179224.aspx
                           
$info['fileformat'] = 'zip.msoffice';
                           if (!empty(
$ThisFileInfo['zip']['files']['ppt'])) {
                              
$info['mime_type'] = 'application/vnd.openxmlformats-officedocument.presentationml.presentation';
                           } elseif (!empty(
$ThisFileInfo['zip']['files']['xl'])) {
                              
$info['mime_type'] = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
                           } elseif (!empty(
$ThisFileInfo['zip']['files']['word'])) {
                              
$info['mime_type'] = 'application/vnd.openxmlformats-officedocument.wordprocessingml.document';
                           }
                    }

                    return 
true;
                }
            }
        }

        if (!
$this->getZIPentriesFilepointer()) {
            unset(
$info['zip']);
            
$info['fileformat'] = '';
            
$info['error'][] = 'Cannot find End Of Central Directory (truncated file?)';
            return 
false;
        }

        
// central directory couldn't be found and/or parsed
        // scan through actual file data entries, recover as much as possible from probable trucated file
        
if ($info['zip']['compressed_size'] > ($info['filesize'] - 46 22)) {
            
$info['error'][] = 'Warning: Truncated file! - Total compressed file sizes ('.$info['zip']['compressed_size'].' bytes) is greater than filesize minus Central Directory and End Of Central Directory structures ('.($info['filesize'] - 46 22).' bytes)';
        }
        
$info['error'][] = 'Cannot find End Of Central Directory - returned list of files in [zip][entries] array may not be complete';
        foreach (
$info['zip']['entries'] as $key => $valuearray) {
            
$info['zip']['files'][$valuearray['filename']] = $valuearray['uncompressed_size'];
        }
        return 
true;
    }


    public function 
getZIPHeaderFilepointerTopDown() {
        
$info = &$this->getid3->info;

        
$info['fileformat'] = 'zip';

        
$info['zip']['compressed_size']   = 0;
        
$info['zip']['uncompressed_size'] = 0;
        
$info['zip']['entries_count']     = 0;

        
rewind($this->getid3->fp);
        while (
$fileentry $this->ZIPparseLocalFileHeader()) {
            
$info['zip']['entries'][] = $fileentry;
            
$info['zip']['entries_count']++;
        }
        if (
$info['zip']['entries_count'] == 0) {
            
$info['error'][] = 'No Local File Header entries found';
            return 
false;
        }

        
$info['zip']['entries_count']     = 0;
        while (
$centraldirectoryentry $this->ZIPparseCentralDirectory($this->getid3->fp)) {
            
$info['zip']['central_directory'][] = $centraldirectoryentry;
            
$info['zip']['entries_count']++;
            
$info['zip']['compressed_size']   += $centraldirectoryentry['compressed_size'];
            
$info['zip']['uncompressed_size'] += $centraldirectoryentry['uncompressed_size'];
        }
        if (
$info['zip']['entries_count'] == 0) {
            
$info['error'][] = 'No Central Directory entries found (truncated file?)';
            return 
false;
        }

        if (
$EOCD $this->ZIPparseEndOfCentralDirectory()) {
            
$info['zip']['end_central_directory'] = $EOCD;
        } else {
            
$info['error'][] = 'No End Of Central Directory entry found (truncated file?)';
            return 
false;
        }

        if (!empty(
$info['zip']['end_central_directory']['comment'])) {
            
$info['zip']['comments']['comment'][] = $info['zip']['end_central_directory']['comment'];
        }

        return 
true;
    }


    public function 
getZIPentriesFilepointer() {
        
$info = &$this->getid3->info;

        
$info['zip']['compressed_size']   = 0;
        
$info['zip']['uncompressed_size'] = 0;
        
$info['zip']['entries_count']     = 0;

        
rewind($this->getid3->fp);
        while (
$fileentry $this->ZIPparseLocalFileHeader()) {
            
$info['zip']['entries'][] = $fileentry;
            
$info['zip']['entries_count']++;
            
$info['zip']['compressed_size']   += $fileentry['compressed_size'];
            
$info['zip']['uncompressed_size'] += $fileentry['uncompressed_size'];
        }
        if (
$info['zip']['entries_count'] == 0) {
            
$info['error'][] = 'No Local File Header entries found';
            return 
false;
        }

        return 
true;
    }


    public function 
ZIPparseLocalFileHeader() {
        
$LocalFileHeader['offset'] = $this->ftell();

        
$ZIPlocalFileHeader $this->fread(30);

        
$LocalFileHeader['raw']['signature']          = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader,  04));
        if (
$LocalFileHeader['raw']['signature'] != 0x04034B50) { // "PK\x03\x04"
            // invalid Local File Header Signature
            
$this->fseek($LocalFileHeader['offset']); // seek back to where filepointer originally was so it can be handled properly
            
return false;
        }
        
$LocalFileHeader['raw']['extract_version']    = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader,  42));
        
$LocalFileHeader['raw']['general_flags']      = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader,  62));
        
$LocalFileHeader['raw']['compression_method'] = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader,  82));
        
$LocalFileHeader['raw']['last_mod_file_time'] = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader102));
        
$LocalFileHeader['raw']['last_mod_file_date'] = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader122));
        
$LocalFileHeader['raw']['crc_32']             = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader144));
        
$LocalFileHeader['raw']['compressed_size']    = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader184));
        
$LocalFileHeader['raw']['uncompressed_size']  = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader224));
        
$LocalFileHeader['raw']['filename_length']    = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader262));
        
$LocalFileHeader['raw']['extra_field_length'] = getid3_lib::LittleEndian2Int(substr($ZIPlocalFileHeader282));

        
$LocalFileHeader['extract_version']           = sprintf('%1.1f'$LocalFileHeader['raw']['extract_version'] / 10);
        
$LocalFileHeader['host_os']                   = $this->ZIPversionOSLookup(($LocalFileHeader['raw']['extract_version'] & 0xFF00) >> 8);
        
$LocalFileHeader['compression_method']        = $this->ZIPcompressionMethodLookup($LocalFileHeader['raw']['compression_method']);
        
$LocalFileHeader['compressed_size']           = $LocalFileHeader['raw']['compressed_size'];
        
$LocalFileHeader['uncompressed_size']         = $LocalFileHeader['raw']['uncompressed_size'];
        
$LocalFileHeader['flags']                     = $this->ZIPparseGeneralPurposeFlags($LocalFileHeader['raw']['general_flags'], $LocalFileHeader['raw']['compression_method']);
        
$LocalFileHeader['last_modified_timestamp']   = $this->DOStime2UNIXtime($LocalFileHeader['raw']['last_mod_file_date'], $LocalFileHeader['raw']['last_mod_file_time']);

        
$FilenameExtrafieldLength $LocalFileHeader['raw']['filename_length'] + $LocalFileHeader['raw']['extra_field_length'];
        if (
$FilenameExtrafieldLength 0) {
            
$ZIPlocalFileHeader .= $this->fread($FilenameExtrafieldLength);

            if (
$LocalFileHeader['raw']['filename_length'] > 0) {
                
$LocalFileHeader['filename']                = substr($ZIPlocalFileHeader30$LocalFileHeader['raw']['filename_length']);
            }
            if (
$LocalFileHeader['raw']['extra_field_length'] > 0) {
                
$LocalFileHeader['raw']['extra_field_data'] = substr($ZIPlocalFileHeader30 $LocalFileHeader['raw']['filename_length'], $LocalFileHeader['raw']['extra_field_length']);
            }
        }

        if (
$LocalFileHeader['compressed_size'] == 0) {
            
// *Could* be a zero-byte file
            // But could also be a file written on the fly that didn't know compressed filesize beforehand.
            // Correct compressed filesize should be in the data_descriptor located after this file data, and also in Central Directory (at end of zip file)
            
if (!empty($this->getid3->info['zip']['central_directory'])) {
                foreach (
$this->getid3->info['zip']['central_directory'] as $central_directory_entry) {
                    if (
$central_directory_entry['entry_offset'] == $LocalFileHeader['offset']) {
                        if (
$central_directory_entry['compressed_size'] > 0) {
                            
// overwrite local zero value (but not ['raw']'compressed_size']) so that seeking for data_descriptor (and next file entry) works correctly
                            
$LocalFileHeader['compressed_size'] = $central_directory_entry['compressed_size'];
                        }
                        break;
                    }
                }
            }

        }
        
$LocalFileHeader['data_offset'] = $this->ftell();
        
$this->fseek($LocalFileHeader['compressed_size'], SEEK_CUR); // this should (but may not) match value in $LocalFileHeader['raw']['compressed_size'] -- $LocalFileHeader['compressed_size'] could have been overwritten above with value from Central Directory

        
if ($LocalFileHeader['flags']['data_descriptor_used']) {
            
$DataDescriptor $this->fread(16);
            
$LocalFileHeader['data_descriptor']['signature']         = getid3_lib::LittleEndian2Int(substr($DataDescriptor,  04));
            if (
$LocalFileHeader['data_descriptor']['signature'] != 0x08074B50) { // "PK\x07\x08"
                
$this->getid3->warning[] = 'invalid Local File Header Data Descriptor Signature at offset '.($this->ftell() - 16).' - expecting 08 07 4B 50, found '.getid3_lib::PrintHexBytes($LocalFileHeader['data_descriptor']['signature']);
                
$this->fseek($LocalFileHeader['offset']); // seek back to where filepointer originally was so it can be handled properly
                
return false;
            }
            
$LocalFileHeader['data_descriptor']['crc_32']            = getid3_lib::LittleEndian2Int(substr($DataDescriptor,  44));
            
$LocalFileHeader['data_descriptor']['compressed_size']   = getid3_lib::LittleEndian2Int(substr($DataDescriptor,  84));
            
$LocalFileHeader['data_descriptor']['uncompressed_size'] = getid3_lib::LittleEndian2Int(substr($DataDescriptor124));
            if (!
$LocalFileHeader['raw']['compressed_size'] && $LocalFileHeader['data_descriptor']['compressed_size']) {
                foreach (
$this->getid3->info['zip']['central_directory'] as $central_directory_entry) {
                    if (
$central_directory_entry['entry_offset'] == $LocalFileHeader['offset']) {
                        if (
$LocalFileHeader['data_descriptor']['compressed_size'] == $central_directory_entry['compressed_size']) {
                            
// $LocalFileHeader['compressed_size'] already set from Central Directory
                        
} else {
                            
$this->getid3->info['warning'][] = 'conflicting compressed_size from data_descriptor ('.$LocalFileHeader['data_descriptor']['compressed_size'].') vs Central Directory ('.$central_directory_entry['compressed_size'].') for file at offset '.$LocalFileHeader['offset'];
                        }

                        if (
$LocalFileHeader['data_descriptor']['uncompressed_size'] == $central_directory_entry['uncompressed_size']) {
                            
$LocalFileHeader['uncompressed_size'] = $LocalFileHeader['data_descriptor']['uncompressed_size'];
                        } else {
                            
$this->getid3->info['warning'][] = 'conflicting uncompressed_size from data_descriptor ('.$LocalFileHeader['data_descriptor']['uncompressed_size'].') vs Central Directory ('.$central_directory_entry['uncompressed_size'].') for file at offset '.$LocalFileHeader['offset'];
                        }
                        break;
                    }
                }
            }
        }
        return 
$LocalFileHeader;
    }


    public function 
ZIPparseCentralDirectory() {
        
$CentralDirectory['offset'] = $this->ftell();

        
$ZIPcentralDirectory $this->fread(46);

        
$CentralDirectory['raw']['signature']            = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory,  04));
        if (
$CentralDirectory['raw']['signature'] != 0x02014B50) {
            
// invalid Central Directory Signature
            
$this->fseek($CentralDirectory['offset']); // seek back to where filepointer originally was so it can be handled properly
            
return false;
        }
        
$CentralDirectory['raw']['create_version']       = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory,  42));
        
$CentralDirectory['raw']['extract_version']      = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory,  62));
        
$CentralDirectory['raw']['general_flags']        = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory,  82));
        
$CentralDirectory['raw']['compression_method']   = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory102));
        
$CentralDirectory['raw']['last_mod_file_time']   = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory122));
        
$CentralDirectory['raw']['last_mod_file_date']   = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory142));
        
$CentralDirectory['raw']['crc_32']               = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory164));
        
$CentralDirectory['raw']['compressed_size']      = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory204));
        
$CentralDirectory['raw']['uncompressed_size']    = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory244));
        
$CentralDirectory['raw']['filename_length']      = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory282));
        
$CentralDirectory['raw']['extra_field_length']   = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory302));
        
$CentralDirectory['raw']['file_comment_length']  = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory322));
        
$CentralDirectory['raw']['disk_number_start']    = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory342));
        
$CentralDirectory['raw']['internal_file_attrib'] = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory362));
        
$CentralDirectory['raw']['external_file_attrib'] = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory384));
        
$CentralDirectory['raw']['local_header_offset']  = getid3_lib::LittleEndian2Int(substr($ZIPcentralDirectory424));

        
$CentralDirectory['entry_offset']              = $CentralDirectory['raw']['local_header_offset'];
        
$CentralDirectory['create_version']            = sprintf('%1.1f'$CentralDirectory['raw']['create_version'] / 10);
        
$CentralDirectory['extract_version']           = sprintf('%1.1f'$CentralDirectory['raw']['extract_version'] / 10);
        
$CentralDirectory['host_os']                   = $this->ZIPversionOSLookup(($CentralDirectory['raw']['extract_version'] & 0xFF00) >> 8);
        
$CentralDirectory['compression_method']        = $this->ZIPcompressionMethodLookup($CentralDirectory['raw']['compression_method']);
        
$CentralDirectory['compressed_size']           = $CentralDirectory['raw']['compressed_size'];
        
$CentralDirectory['uncompressed_size']         = $CentralDirectory['raw']['uncompressed_size'];
        
$CentralDirectory['flags']                     = $this->ZIPparseGeneralPurposeFlags($CentralDirectory['raw']['general_flags'], $CentralDirectory['raw']['compression_method']);
        
$CentralDirectory['last_modified_timestamp']   = $this->DOStime2UNIXtime($CentralDirectory['raw']['last_mod_file_date'], $CentralDirectory['raw']['last_mod_file_time']);

        
$FilenameExtrafieldCommentLength $CentralDirectory['raw']['filename_length'] + $CentralDirectory['raw']['extra_field_length'] + $CentralDirectory['raw']['file_comment_length'];
        if (
$FilenameExtrafieldCommentLength 0) {
            
$FilenameExtrafieldComment $this->fread($FilenameExtrafieldCommentLength);

            if (
$CentralDirectory['raw']['filename_length'] > 0) {
                
$CentralDirectory['filename']                  = substr($FilenameExtrafieldComment0$CentralDirectory['raw']['filename_length']);
            }
            if (
$CentralDirectory['raw']['extra_field_length'] > 0) {
                
$CentralDirectory['raw']['extra_field_data']   = substr($FilenameExtrafieldComment$CentralDirectory['raw']['filename_length'], $CentralDirectory['raw']['extra_field_length']);
            }
            if (
$CentralDirectory['raw']['file_comment_length'] > 0) {
                
$CentralDirectory['file_comment']              = substr($FilenameExtrafieldComment$CentralDirectory['raw']['filename_length'] + $CentralDirectory['raw']['extra_field_length'], $CentralDirectory['raw']['file_comment_length']);
            }
        }

        return 
$CentralDirectory;
    }

    public function 
ZIPparseEndOfCentralDirectory() {
        
$EndOfCentralDirectory['offset'] = $this->ftell();

        
$ZIPendOfCentralDirectory $this->fread(22);

        
$EndOfCentralDirectory['signature']                   = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory,  04));
        if (
$EndOfCentralDirectory['signature'] != 0x06054B50) {
            
// invalid End Of Central Directory Signature
            
$this->fseek($EndOfCentralDirectory['offset']); // seek back to where filepointer originally was so it can be handled properly
            
return false;
        }
        
$EndOfCentralDirectory['disk_number_current']         = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory,  42));
        
$EndOfCentralDirectory['disk_number_start_directory'] = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory,  62));
        
$EndOfCentralDirectory['directory_entries_this_disk'] = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory,  82));
        
$EndOfCentralDirectory['directory_entries_total']     = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory102));
        
$EndOfCentralDirectory['directory_size']              = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory124));
        
$EndOfCentralDirectory['directory_offset']            = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory164));
        
$EndOfCentralDirectory['comment_length']              = getid3_lib::LittleEndian2Int(substr($ZIPendOfCentralDirectory202));

        if (
$EndOfCentralDirectory['comment_length'] > 0) {
            
$EndOfCentralDirectory['comment']                 = $this->fread($EndOfCentralDirectory['comment_length']);
        }

        return 
$EndOfCentralDirectory;
    }


    public static function 
ZIPparseGeneralPurposeFlags($flagbytes$compressionmethod) {
        
// https://users.cs.jmu.edu/buchhofp/forensics/formats/pkzip-printable.html
        
$ParsedFlags['encrypted']               = (bool) ($flagbytes 0x0001);
        
//                                                             0x0002 -- see below
        //                                                             0x0004 -- see below
        
$ParsedFlags['data_descriptor_used']    = (bool) ($flagbytes 0x0008);
        
$ParsedFlags['enhanced_deflation']      = (bool) ($flagbytes 0x0010);
        
$ParsedFlags['compressed_patched_data'] = (bool) ($flagbytes 0x0020);
        
$ParsedFlags['strong_encryption']       = (bool) ($flagbytes 0x0040);
        
//                                                             0x0080 - unused
        //                                                             0x0100 - unused
        //                                                             0x0200 - unused
        //                                                             0x0400 - unused
        
$ParsedFlags['language_encoding']       = (bool) ($flagbytes 0x0800);
        
//                                                             0x1000 - reserved
        
$ParsedFlags['mask_header_values']      = (bool) ($flagbytes 0x2000);
        
//                                                             0x4000 - reserved
        //                                                             0x8000 - reserved

        
switch ($compressionmethod) {
            case 
6:
                
$ParsedFlags['dictionary_size']    = (($flagbytes 0x0002) ? 8192 4096);
                
$ParsedFlags['shannon_fano_trees'] = (($flagbytes 0x0004) ? 3    2);
                break;

            case 
8:
            case 
9:
                switch ((
$flagbytes 0x0006) >> 1) {
                    case 
0:
                        
$ParsedFlags['compression_speed'] = 'normal';
                        break;
                    case 
1:
                        
$ParsedFlags['compression_speed'] = 'maximum';
                        break;
                    case 
2:
                        
$ParsedFlags['compression_speed'] = 'fast';
                        break;
                    case 
3:
                        
$ParsedFlags['compression_speed'] = 'superfast';
                        break;
                }
                break;
        }

        return 
$ParsedFlags;
    }


    public static function 
ZIPversionOSLookup($index) {
        static 
$ZIPversionOSLookup = array(
            
0  => 'MS-DOS and OS/2 (FAT / VFAT / FAT32 file systems)',
            
1  => 'Amiga',
            
2  => 'OpenVMS',
            
3  => 'Unix',
            
4  => 'VM/CMS',
            
5  => 'Atari ST',
            
6  => 'OS/2 H.P.F.S.',
            
7  => 'Macintosh',
            
8  => 'Z-System',
            
9  => 'CP/M',
            
10 => 'Windows NTFS',
            
11 => 'MVS',
            
12 => 'VSE',
            
13 => 'Acorn Risc',
            
14 => 'VFAT',
            
15 => 'Alternate MVS',
            
16 => 'BeOS',
            
17 => 'Tandem',
            
18 => 'OS/400',
            
19 => 'OS/X (Darwin)',
        );

        return (isset(
$ZIPversionOSLookup[$index]) ? $ZIPversionOSLookup[$index] : '[unknown]');
    }

    public static function 
ZIPcompressionMethodLookup($index) {
        
// http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/ZIP.html
        
static $ZIPcompressionMethodLookup = array(
            
0  => 'store',
            
1  => 'shrink',
            
2  => 'reduce-1',
            
3  => 'reduce-2',
            
4  => 'reduce-3',
            
5  => 'reduce-4',
            
6  => 'implode',
            
7  => 'tokenize',
            
8  => 'deflate',
            
9  => 'deflate64',
            
10 => 'Imploded (old IBM TERSE)',
            
11 => 'RESERVED[11]',
            
12 => 'BZIP2',
            
13 => 'RESERVED[13]',
            
14 => 'LZMA (EFS)',
            
15 => 'RESERVED[15]',
            
16 => 'RESERVED[16]',
            
17 => 'RESERVED[17]',
            
18 => 'IBM TERSE (new)',
            
19 => 'IBM LZ77 z Architecture (PFS)',
            
96 => 'JPEG recompressed',
            
97 => 'WavPack compressed',
            
98 => 'PPMd version I, Rev 1',
        );

        return (isset(
$ZIPcompressionMethodLookup[$index]) ? $ZIPcompressionMethodLookup[$index] : '[unknown]');
    }

    public static function 
DOStime2UNIXtime($DOSdate$DOStime) {
        
// wFatDate
        // Specifies the MS-DOS date. The date is a packed 16-bit value with the following format:
        // Bits      Contents
        // 0-4    Day of the month (1-31)
        // 5-8    Month (1 = January, 2 = February, and so on)
        // 9-15   Year offset from 1980 (add 1980 to get actual year)

        
$UNIXday    =  ($DOSdate 0x001F);
        
$UNIXmonth  = (($DOSdate 0x01E0) >> 5);
        
$UNIXyear   = (($DOSdate 0xFE00) >> 9) + 1980;

        
// wFatTime
        // Specifies the MS-DOS time. The time is a packed 16-bit value with the following format:
        // Bits   Contents
        // 0-4    Second divided by 2
        // 5-10   Minute (0-59)
        // 11-15  Hour (0-23 on a 24-hour clock)

        
$UNIXsecond =  ($DOStime 0x001F) * 2;
        
$UNIXminute = (($DOStime 0x07E0) >> 5);
        
$UNIXhour   = (($DOStime 0xF800) >> 11);

        return 
gmmktime($UNIXhour$UNIXminute$UNIXsecond$UNIXmonth$UNIXday$UNIXyear);
    }

}