<?php
// new zip class, re-written a bit to work with existing class in 6.3.5 for bug fix
class Zip {
	var $_fp;
	var $_size;
	var $_cd;
	var $_ecdr;
	var $_tbl;

	function open($file) {
		if(false === ($this->_fp = @fopen($file, 'rb')))
			return false;
		$this->_size = filesize($file);
		return $this->_getCD();
	}

	function close() {
		@fclose($this->_fp);
	}

	// reset the internal array pointer on the CD
	function rewind() {
		reset($this->_cd);
	}

	// return the next entry
	function getFileNew($content = false) {
		list(, $f) = each($this->_cd);
		if(!$f)
			return false;
		$f = $this->_normalize($f);
		if($content)
			$f['content'] = $this->extractFile($f);
		return $f;
	}

	function getFile($name = '') {
		if($name == '') {
			return $this->getFileNew(true);
		} else {
			for($i = 0, $c = count($this->_cd); $i < $c; $i++) {
				$tmp = $this->_normalize($this->_cd[$i]);
				if($tmp['name'] == $name);
					$tmp['content'] = $this->extractFile($name);
				return $tmp;
			}
		}
		return false;
	}

	// return all entries
	function getFileList() {
		$list = array();
		for($i = 0, $c = count($this->_cd); $i < $c; $i++) {
			$tmp = $this->_normalize($this->_cd[$i]);
			$list[] = $tmp['name'];
		}
		return $list;
	}

	// return zip file info
	function getInfo() {
		return array (
			'entries' => $this->_ecdr['disk_cdr_entries_num'],
			'comment' => $this->_ecdr['comment']
		);
	}

	// Extract file content to $target.
	// $path can be file path or array from getFile().
	// If $target is path to directory, create a file named after the file and write to it
	// If $target is path to file, open/create file and write to it
	// If $target is false, return content
	// Return false if fails.
	function extractFile($path, $target = false) {
		$path = is_array($path) ? $path['path'] : $path;
		if(!isset($this->_tbl[$path]))
			return false;
		$file = $this->_cd[$this->_tbl[$path]];

		// if $file is_dir, create dir in $target if it's a dir
		if($file['is_dir'] && is_dir($target)) {
			return mkdir($target . '/' . $file['path']);
		}

		// read past local file header to the file content
		$lfh_offset = $file['rel_offset'];
		if(fseek($this->_fp, $lfh_offset, SEEK_SET) !== 0)
			return false;
		$lfh_data = fread($this->_fp, 30);
		if(strlen($lfh_data) != 30)
			return false;
		$lfh = unpack('Vheader_sig/Sversion_extract/Sgen_purpose/Scompression_method'
			. '/Slast_mod_time/Slast_mod_date/Vcrc_32/Vcompressed_size'
			. '/Vuncompressed_size/Sfilename_len/Sextra_field_len', $lfh_data);
		$offset = $lfh['filename_len'] + $lfh['extra_field_len'];
		if(fseek($this->_fp, $offset, SEEK_CUR) !== 0)
			return false;
		$content = $lfh['compressed_size'] ? fread($this->_fp, $lfh['compressed_size']) : '';
		if($lfh['compression_method'] == 8 && strlen($content))
			$content = gzinflate($content);

		if(!$target)
			return $content;
		if(is_resource($target))
			return fwrite($target, $content);

		$fp = null;
		if(is_dir($target)) {
			$fp = is_dir($target . '/' . dirname($file['path']))
				? fopen($target . '/' . $file['path'], 'wb')
				: fopen($target . '/' . $file['filename'], 'wb');
		} else {
			$fp = fopen($target, 'wb');
		}
		if($fp) {
			fwrite($fp, $content);
			fclose($fp);
			return true;
		}
		return false;
	}

	// translate CD entry to normalized info array
	function _normalize($entry) {
		return array (
			'path' => $entry['path'],
			'name' => $entry['filename'],
			'size' => $entry['uncompressed_size'],
			'csize'=> $entry['compressed_size'],
			'is_dir' => $entry['is_dir'],
			'comment'=> $entry['comment']
		);
	}

	// read in Central Directory
	// return true/false
	function _getCD() {
		if(fseek($this->_fp, -22, SEEK_END) !== 0)
			return false;
		$ecdr_data = fread($this->_fp, 22);
		if(strlen($ecdr_data) !== 22)
			return false;
		$ecdr = unpack('Vcdr_sig/vdisk_num/vcdr_disk_num/vdisk_cdr_entries_num'
			. '/vcdr_entries_num/Vcdr_size/Vstart_disk_cdr_offset'
			. '/vcomment_len', $ecdr_data);
		if($ecdr['cdr_sig'] === 0x06054b50) {
			$ecdr['comment'] = '';
		} else {
			$seek_pos = min(65558, $this->_size);
			if(fseek($this->_fp, -$seek_pos, SEEK_END) !== 0)
				return false;
			$ecdr_max = fread($this->_fp, 65558);
			if(false === ($ecdr_offset = strpos($ecdr_max, "\x50\x4b\x05\x06")))
				return false;
			$ecdr_data = substr($ecdr_max, $ecdr_offset, 22);
			$ecdr = unpack('Vcdr_sig/vdisk_num/vcdr_disk_num'
				. '/vdisk_cdr_entries_num/vcdr_entries_num/Vcdr_size'
				. '/Vstart_disk_cdr_offset/vcomment_len', $ecdr_data);
			$ecdr['comment'] = substr($ecdr_max, $ecdr_offset + 22, $ecdr['comment_len']);
		}
		$this->_ecdr = $ecdr;

		// got ECDR, get CD
		if(fseek($this->_fp, $ecdr['start_disk_cdr_offset'], SEEK_SET) !== 0)
			return false;
		for($i = 0, $c = $ecdr['disk_cdr_entries_num']; $i < $c; $i++) {
			$fh_data = fread($this->_fp, 46);
			if(strlen($fh_data) != 46 || feof($this->_fp))
				return false;
			$fh = unpack('Vcfh_sig/Cversion_made_by_lower/Cversion_made_by_upper'
				. '/vv_extract/vgen_flag/vcomppression_method/vmod_time'
				. '/vmode_date/Ncrc32/Vcompressed_size/Vuncompressed_size'
				. '/vfilename_len/vxtra_len/vcomment_len/vdisk_num_start'
				. '/vinternal_attrib/Vexternal_attrib/Vrel_offset', $fh_data);
			if(!is_array($fh) || $fh['cfh_sig'] != 33639248)
				return false;
			$len = $fh['filename_len'] + $fh['xtra_len'] + $fh['comment_len'];
			$data = fread($this->_fp, $len);
			$fh['path'] = substr($data, 0, $fh['filename_len']);
			$fh['name'] = $fh['path'];
			$fh['filename'] = basename($fh['path']);
			$fh['extra'] = substr($data, $fh['filename_len'], $fh['xtra_len']);
			$fh['comment'] = substr($data, $fh['filename_len'] + $fh['xtra_len'], $fh['comment_len']);
			$fh['is_dir'] = $fh['version_made_by_upper'] == 0 && ($fh['external_attrib'] & 16);
			$this->_tbl["{$fh['path']}"] = count($this->_cd);
			$this->_cd[] = $fh;
		}
		return true;
	}

	function _getEntry($lfh_offset) {
		if(fseek($this->_fp, $lfh_offset, SEEK_SET) !== 0)
			return false;
		$lfh = unpack('Vheader_sig/Sversion_extract/Sgen_purpose/Scompression_method/Slast_mod_time/Slast_mod_date/Vcrc_32/Vcompressed_size/Vuncompressed_size/Sfile_name_length/Sextra_field_length', fread($this->_fp, 30));
		$lfh['name'] = $lfh['file_name_length'] ? fread($this->_fp, $lfh['file_name_length']) : '';
		$lfh['extra_field'] = $lfh['extra_field_length'] ? fread($this->_fp, $lfh['extra_field_length']) : '';
		if($lfh['compression_method'] == 8) $file_content = $lfh['compressed_size'] ? @gzinflate(fread($this->_fp, $lfh['compressed_size'])) : '';
		elseif($lfh['compression_method'] == 0) $file_content = $lfh['compressed_size'] ? fread($this->_fp, $lfh['compressed_size']) : '';
		else return false;
		$ldd = $lfh['gen_purpose'] & 8 ? unpack('Vcrc_32/Vcompressed_size/Vuncompressed_size', fread($this->_fp, 12)) : '';
		return array('name' => $lfh['name'], 'size' => $lfh['uncompressed_size'], 'content' => &$file_content);
	}
}

?>