<?php
/*
 |  ZIP         A ZipArchive and Plain PKZIP PHP Helper
 |  @file       ./PIT/ZIP.php
 |  @author     SamBrishes <sam@pytes.net>
 |  @version    0.2.1 [0.2.1] - Beta
 |
 |  @license    X11 / MIT License
 |  @copyright  Copyright © 2015 - 2019 SamBrishes, pytesNET <info@pytes.net>
 */
/*
 |  The following websites contains all required informations, which were unavoidable for the
 |  creation of this class:
 |
 |  -   https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT
 |  -   https://users.cs.jmu.edu/buchhofp/forensics/formats/pkzip.html
 |  -   https://php.net/manual/class.ziparchive.php
 */

    namespace PIT;

    class Zip{
        const FLAGS = "\x00\x00";
        const VERSION = "\x14\x00";
        const SIGNATURE = "\x50\x4b";
        const COMPRESSION = "\x08\x00";

        /*
         |  SETTINGs
         */
        public $zipArchive = false;
        public $compression = 6;

        /*
         |  ZIP ARCHIVE
         */
        private $zipFilename;
        private $zipInstance;

        /*
         |  FALLBACK
         */
        private $offset = 0;
        private $headers = array();
        private $central = array();
        private $counter = 0;

        /*
         |  CONSTRUCTOR
         |  @since  0.2.0
         |
         |  @param  bool    TRUE to check and use ZipArchive if available,
         |                  FALSE to use the PKZIP PHP compression per default.
         |  @return int     The compression level between -1 and 9.
         */
        public function __construct($ziparchive = false, $compression = 6){
            if($ziparchive){
                $this->zipArchive = class_exists("ZipArchive", false);
                $this->zipInstance = ($this->zipArchive)? new ZipArchive(): false;
            }
            if($this->zipArchive){
                $this->zipFilename = tempnam(sys_get_temp_dir(), "tzp") . ".zip";
                $this->zipInstance->open($this->zipFilename, ZipArchive::CREATE);
            }
            $this->compression = ($compression >= -1 && $compression <= 9)? $compression: 6;
        }

        /*
         |  DESTRUCTOR
         |  @since  0.2.0
         */
        public function __destruct(){
            $this->clear(false);
        }

        /*
         |  HELPER :: CONVERT UNIX TO DOS TIME
         |  @since  0.2.1
         |
         |  @param  int     The respective timestamp as INTEGER.
         */
        protected function msDOSTime($time){
            $array = getdate((is_int($time) && $time > 0)? $time: time());
            if($array["year"] < 1980 || $array["year"] > 2107){
                $array = getdate(time());
            }

            // Return as DEC
            return (
                (($array["year"]-1980 << 25)) |
                (($array["mon"]       << 21)) |
                (($array["mday"]      << 16)) |
                (($array["hours"]     << 11)) |
                (($array["minutes"]   <<  5)) |
                (($array["seconds"]   >>  1))
            );
        }

        /*
         |  ADD A FILE
         |  @since  0.1.0
         |  @update 0.2.1
         |
         |  @param  string  The relative or absolute filepath or the respective file content.
         |  @param  string  The local path within the archive file.
         |  @param  int     The timestamp to use.
         |  @param  string  The optional file comment or just an empty string.
         |
         |  @return bool    TRUE on success, FALSE on failure.
         */
        public function addFile($data, $path, $time = 0, $comment = ""){
            if((!is_string($data) && !is_numeric($data)) || !is_string($path)){
                return false;
            }

            // Sanitize Data
            if(is_string($data) && file_exists($data) && is_file($data)){
                $data = file_get_contents($data);
            }
            $path = trim(str_replace("\\", "/", $path), "/");
            $time = $this->msDOSTime($time);

            // Zip Archive
            if($this->zipArchive){
                return $this->zipInstance->addFromString($path, $data);
            }

            // Fallback
            $crcval = crc32($data);
            $length = strlen($data);
            if(version_compare(PHP_VERSION, "5.4.0", ">=")){
                $gzcval = gzcompress($data, $this->compression, ZLIB_ENCODING_DEFLATE);
            } else {
                $gzcval = gzcompress($data, $this->compression);
            }
            $gzcval = substr($gzcval, 2, strlen($gzcval) - 6); // Fix CRC-32 Bug
            $gzclen = strlen($gzcval);

            /*
             |  LOCAL FILE HEADER
             |  01      SIGNATURE
             |  02      Version needed to extract this archive.
             |  03      General purpose bit flag.
             |  04      Compression method.
             |  05      Last modification DOS datetime.
             |  06      CRC32 value.
             |  07      Compressed Filesize.
             |  08      Uncompressed Filesize.
             |  09      Length of the filename inside the archive.
             |  10      Length of the extra fields.
             |  11      The relative path / filename inside the archive.
             |  12      The main file data value.
             */
            $this->headers[] =
                self::SIGNATURE . "\x03\x04" .
                self::VERSION .
                self::FLAGS .
                self::COMPRESSION .
                pack("V", $time) .
                pack("V", $crcval) .
                pack("V", $gzclen) .
                pack("V", $length) .
                pack("v", strlen($path)) .
                pack("v", 0) .
                $path .
                $gzcval;

            /*
             |  CENTRAL DIRECTORY RECORD
             |  01      SIGNATURE
             |  02      MadeBy Version numbers.
             |  03      Version needed to extract this archive.
             |  04      General purpose bit flag.
             |  05      Compression method.
             |  06      Last modification DOS datetime.
             |  07      CRC32 value.
             |  08      Compressed Filesize.
             |  09      Uncompressed Filesize.
             |  10      Length of the filename inside the archive.
             |  11      Length of the extra fields.
             |  12      Length of the file comment.
             |  13      The disk number where the file exists.
             |  14      Internal file attributes.
             |  15      External file attributes.
             |  16      Offset of the local file header.
             |  17      The relative path / filename inside the archive.
             |  18      The file comment.
             */
            $this->central[] =
                self::SIGNATURE . "\x01\x02" .
                "\x00\x00" .
                self::VERSION .
                self::FLAGS .
                self::COMPRESSION .
                pack("V", $time) .
                pack("V", $crcval) .
                pack("V", $gzclen) .
                pack("V", $length) .
                pack("v", strlen($path)) .
                pack("v", 0) .
                pack("v", strlen($comment)) .
                pack("v", 0) .
                pack("v", 0) .
                pack("V", 32) .
                pack("V", $this->offset) .
                $path .
                $comment;

            // Count Offset and Return
            $this->offset += strlen($this->headers[count($this->headers)-1]);
            return true;
        }

        /*
         |  ADD MULTIPLE FILES
         |  @since  0.2.0
         |  @update 0.2.1
         |
         |  @param  array   Multiple 'local/file/path' => "filepath/or/filecontent" ARRAY pairs.
         |  @param  int     The timestamp to use for all files.
         |  @param  string  The optional comment or just an empty string for alle respective files.
         |
         |  @return int     The number of successfully added elements / files.
         */
        public function addFiles($array, $time = 0, $comment = ""){
            if(!is_array($array)){
                return false;
            }
            foreach($array AS $path => &$data){
                $data = $this->addFile($data, $path);
            }
            return array_filter(array_values($array));
        }

        /*
         |  ADD FOLDER
         |  @since  0.2.0
         |
         |  @param  string  The path to the folder, which should be zipped.
         |  @param  string  The local path within the zip file.
         |  @param  bool    TRUE to zip recursive and include all sub directories,
         |                  FALSE to just zip all files within the $path folder.
         |  @param  bool    TRUE to include empty folders on recursive zips.
         |                  FALSE to skip empty folders.
         |
         |  @return multi   The number as INT of successfully added elements / files,
         |                  FALSE on failure.
         */
        public function addFolder($path, $local = "/", $recursive = false, $empty = false){
            if(!file_exists($path) || !is_dir($path)){
                return false;
            }

            // Chech Path
            $path = str_replace(array("/", "\\"), DIRECTORY_SEPARATOR, realpath($path));
            if(strpos($path, DIRECTORY_SEPARATOR) !== strlen($path)-1){
                $path .= DIRECTORY_SEPARATOR;
            }

            // Check Local
            if(!is_string($local)){
                $local = "";
            }
            $local = trim(str_replace("\\", "/", $local), "/") . "/";

            // Start Flow
            $this->counter = 0;
            $this->addFolderFlow($path, "", $local, !!$recursive, !!$empty);
            return $this->counter;
        }

        /*
         |  HELPER :: ADD FOLDER LOOP
         |  @since  0.2.0
         |
         |  @param  string  The base path to the folder, which should be zipped.
         |  @param  string  The further path, within the base path, on recursive calls.
         |  @param  string  The local path within the zip file.
         |  @param  bool    TRUE to zip recursive and include all sub directories,
         |                  FALSE to just zip all files within the $path folder.
         |  @param  bool    TRUE to include empty folders on recursive zips.
         |                  FALSE to skip empty folders.
         |
         |  @return int     The number of successfully added elements / files.
         */
        private function addFolderFlow($base, $path = "", $local = "", $recursive = false, $empty = false){
            $path = str_replace(array("/", "\\"), DIRECTORY_SEPARATOR, $path);
            $path = trim($path, DIRECTORY_SEPARATOR);
            if(!empty($path)){
                $path .= DIRECTORY_SEPARATOR;
            }

            $count = 0;
            $handle = opendir($base . $path);
            while(($file = readdir($handle)) !== false){
                if(in_array($file, array(".", ".."))){
                    continue;
                }
                if(is_dir($base . $path . $file)){
                    if($recursive){
                        $count = $this->addFolderFlow($base, $path . $file, $local, $recursive, $empty);
                        if($count == 0 && $empty){
                            $this->addEmptyFolder($local . $path . $file);
                        }
                    }
                    continue;
                }
                if(is_file($base . $path . $file)){
                    if($this->addFile($base . $path . $file, $local . $path . $file)){
                        $count++;
                        $this->counter++;
                    }
                }
            }
            closedir($handle);
            return $count;
        }

        /*
         |  ADD EMPTY FOLDER
         |  @since  0.2.0
         |  @update 0.2.1
         |
         |  @param  string  The local path structure within the zip file.
         |  @param  int     The timestamp to use.
         |  @param  string  The optional file comment or just an empty string.
         |
         |  @return bool    TRUE on success, FALSE on failure.
         */
        public function addEmptyFolder($path, $time = 0, $comment = ""){
            $path = trim(str_replace("\\", "/", $path), "/") . "/";
            $time = $this->msDOSTime($time);

            // ZipArchive
            if($this->zipArchive){
                return $this->zipInstance->addEmptyDir($path);
            }

            // Add Header
            $this->headers[] =
                self::SIGNATURE . "\x03\x04" .
                self::VERSION .
                self::FLAGS .
                "\x00\x00" .
                pack("V", $time) .
                pack("V", 0) .
                pack("V", 0) .
                pack("V", 0) .
                pack("v", strlen($path)) .
                pack("v", 0) .
                $path .
                "";

            // Add Central
            $this->central[] =
                self::SIGNATURE . "\x01\x02" .
                "\x14\x03" .
                self::VERSION .
                self::FLAGS .
                "\x00\x00" .
                pack("V", $time) .
                pack("V", 0) .
                pack("V", 0) .
                pack("V", 0) .
                pack("v", strlen($path)) .
                pack("v", 0) .
                pack("v", strlen($comment)) .
                pack("v", 0) .
                pack("v", 0) .
                "\x00\x00\xFF\x41" .
                pack("V", $this->offset) .
                $path .
                $comment;

            // Count Offset and Return
            $this->offset += strlen($this->headers[count($this->headers)-1]);
            return true;
        }

        /*
         |  CLEAR DATA STRINGs
         |  @since  0.1.0
         |  @update 0.2.0
         */
        public function clear($new = true){
            if($this->zipArchive){
                if(is_a($this->zipInstance, "ZipArchive")){
                    $this->zipInstance->close();
                }
                if(strpos($this->zipFilename, sys_get_temp_dir()) === 0 && file_exists($this->zipFilename)){
                    @unlink($this->zipFilename);
                }
                if($new){
                    $this->zipFilename = "./temp-".time().".zip";
                    $this->zipInstance = new ZipArchive();
                    $this->zipInstance->open($this->zipFilename, ZipArchive::CREATE);
                }
            }
            $this->offset = 0;
            $this->headers = array();
            $this->central = array();
            return true;
        }

        /*
         |  DUMBS OUT THE FILE
         |  @since  0.1.0
         |  @update 0.2.1
         */
        public function file(){
            $comment = "PKZipped with https://github.com/SamBrishes/FoxCMS/tree/helpers/zip";

            // ZipArchive
            if($this->zipArchive){
                $this->zipInstance->setArchiveComment($comment);
                $this->zipInstance->close();

                $content = file_get_contents($this->zipFilename);

                $this->zipInstance = new ZipArchive();
                $this->zipInstance->open($this->zipFilename);
                return $content;
            }

            // Fallback
            $headers = implode("", $this->headers);
            $central = implode("", $this->central);
            /*
             |  RETURN
             |  01      The file header items.
             |  02      The central directory items.
             |  03      The signature for the end of the central directory record.
             |  04      The number of this disk / part.
             |  05      The number of the disk / part where the central directory starts.
             |  06      The number of central directoy entries on this disk.
             |  07      Total number of entries on this disk / part.
             |  08      Total number of entries in general.
             |  09      Length of the central directory.
             |  10      Offset where the central directory starts.
             |  11      The length of the following comment field.
             |  12      The archive comment.
             */
            return $headers . $central .
                self::SIGNATURE . "\x05\x06" .
                "\x00" .
                "\x00" .
                "\x00" .
                "\x00" .
                pack("v", count($this->central)) .
                pack("v", count($this->central)) .
                pack("V", strlen($central)) .
                pack("V", strlen($headers)) .
                pack("v", strlen($comment)) .
                $comment;
        }

        /*
         |  STORE THE ZIP FILE
         |  @since  0.1.0
         |  @update 0.2.0
         |
         |  @param  string  The filename with the respective path to store the archive.
         |  @param  bool    TRUE to overwrite existing archives, FALSE to do it not.
         |
         |  @return bool    TRUE on success, FALSE on failure.
         */
        public function save($filename = "archive.zip", $overwrite = false){
            if(file_exists($filename) && !$overwrite){
                return false;
            }

            // Zip Archive
            if($this->zipArchive){
                if(is_a($this->zipInstance, "ZipArchive")){
                    $this->zipInstance->close();
                }
                if(@file_put_contents($filename, file_get_contents($this->zipFilename))){
                    @unlink($this->zipFilename);

                    $this->zipFilename = $filename;
                    $this->zipInstance = new ZipArchive();
                    return $this->zipInstance->open($this->zipFilename);
                }
                return false;
            }

            // Fallback
            return @file_put_contents($filename, $this->file()) !== false;
        }

        /*
         |  DOWNLOAD THE FILE
         |  @since  0.1.0
         |  @update 0.2.0
         |
         |  @param  string  The filename for the archiv.
         |  @param  bool    TRUE to exit after the execution, FALSE to do it not.
         |
         |  @return void
         */
        public function download($filename = "archive.zip", $exit = false){
            $file = $this->file();
            header("Pragma: public");
            header("Expires: 0");
            header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
            header("Cache-Control: private", false);
            header("Content-Type: application/zip");
            header("Content-Disposition: attachment; filename={$filename};" );
            header("Content-Transfer-Encoding: binary");
            header("Content-Length: " . strlen($file));
            print ($file);
            if($exit){
                die();
            }
        }
    }