<?php
/**
 * TTarFileExtractor class file
 *
 * @author Vincent Blavet <vincent@phpconcept.net>
 */

namespace Prado\IO;

use Prado\Prado;

/* vim: set ts=4 sw=4: */
// +----------------------------------------------------------------------+
// | PHP Version 4                                                        |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2003 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 3.0 of the PHP license,       |
// | that is bundled with this package in the file LICENSE, and is        |
// | available through the world-wide-web at the following url:           |
// | http://www.php.net/license/3_0.txt.                                  |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to          |
// | license@php.net so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Author: Vincent Blavet <vincent@phpconcept.net>                      |
// +----------------------------------------------------------------------+
//
// $Id: TTarFileExtractor.php 3188 2012-07-12 12:13:23Z ctrlaltca $

/**
 * TTarFileExtractor class
 *
 * @author Vincent Blavet <vincent@phpconcept.net>
 * @since 3.0
 */
class TTarFileExtractor
{
	/**
	 * @var string Name of the Tar
	 */
	private $_tarname = '';

	/**
	 * @var null|resource file descriptor
	 */
	private $_file = 0;

	/**
	 * @var string Local Tar name of a remote Tar (http:// or ftp://)
	 */
	private $_temp_tarname = '';

	/**
	 * Archive_Tar Class constructor. This flavour of the constructor only
	 * declare a new Archive_Tar object, identifying it by the name of the
	 * tar file.
	 *
	 * @param    string $p_tarname $p_tarname  The name of the tar archive to create
	 * @access public
	 */
	public function __construct($p_tarname)
	{
		$this->_tarname = $p_tarname;
	}

	public function __destruct()
	{
		$this->_close();
		// ----- Look for a local copy to delete
		if ($this->_temp_tarname != '') {
			@unlink($this->_temp_tarname);
		}
	}

	public function extract($p_path = '')
	{
		return $this->extractModify($p_path, '');
	}

	/**
	 * This method extract all the content of the archive in the directory
	 * indicated by $p_path. When relevant the memorized path of the
	 * files/dir can be modified by removing the $p_remove_path path at the
	 * beginning of the file/dir path.
	 * While extracting a file, if the directory path does not exists it is
	 * created.
	 * While extracting a file, if the file already exists it is replaced
	 * without looking for last modification date.
	 * While extracting a file, if the file already exists and is write
	 * protected, the extraction is aborted.
	 * While extracting a file, if a directory with the same name already
	 * exists, the extraction is aborted.
	 * While extracting a directory, if a file with the same name already
	 * exists, the extraction is aborted.
	 * While extracting a file/directory if the destination directory exist
	 * and is write protected, or does not exist but can not be created,
	 * the extraction is aborted.
	 * If after extraction an extracted file does not show the correct
	 * stored file size, the extraction is aborted.
	 * When the extraction is aborted, a PEAR error text is set and false
	 * is returned. However the result can be a partial extraction that may
	 * need to be manually cleaned.
	 *
	 * @param string $p_path         The path of the directory where the
	 *                               files/dir need to by extracted.
	 * @param string $p_remove_path  Part of the memorized path that can be
	 *                               removed if present at the beginning of
	 *                               the file/dir path.
	 * @return bool               true on success, false on error.
	 * @access public
	 */
	protected function extractModify($p_path, $p_remove_path)
	{
		$v_result = true;
		$v_list_detail = [];

		if ($v_result = $this->_openRead()) {
			$v_result = $this->_extractList(
				$p_path,
				$v_list_detail,
				"complete",
				0,
				$p_remove_path
			);
			$this->_close();
		}

		return $v_result;
	}

	protected function _error($p_message)
	{
		throw new \Exception($p_message);
	}

	private function _isArchive($p_filename = null)
	{
		if ($p_filename == null) {
			$p_filename = $this->_tarname;
		}
		clearstatcache();
		return @is_file($p_filename);
	}

	private function _openRead()
	{
		if (strtolower(substr($this->_tarname, 0, 7)) == 'http://') {

		  // ----- Look if a local copy need to be done
			if ($this->_temp_tarname == '') {
				$this->_temp_tarname = uniqid('tar') . '.tmp';
				if (!$v_file_from = @fopen($this->_tarname, 'rb')) {
					$this->_error('Unable to open in read mode \''
							  . $this->_tarname . '\'');
					$this->_temp_tarname = '';
					return false;
				}
				if (!$v_file_to = @fopen($this->_temp_tarname, 'wb')) {
					$this->_error('Unable to open in write mode \''
							  . $this->_temp_tarname . '\'');
					$this->_temp_tarname = '';
					return false;
				}
				while ($v_data = @fread($v_file_from, 1024)) {
					@fwrite($v_file_to, $v_data);
				}
				@fclose($v_file_from);
				@fclose($v_file_to);
			}

			// ----- File to open if the local copy
			$v_filename = $this->_temp_tarname;
		} else {
			// ----- File to open if the normal Tar file
			$v_filename = $this->_tarname;
		}

		$this->_file = @fopen($v_filename, "rb");

		if ($this->_file == 0) {
			$this->_error('Unable to open in read mode \'' . $v_filename . '\'');
			return false;
		}

		return true;
	}

	private function _close()
	{
		//if (isset($this->_file)) {
		if (is_resource($this->_file)) {
			@fclose($this->_file);
			$this->_file = 0;
		}

		// ----- Look if a local copy need to be erase
		// Note that it might be interesting to keep the url for a time : ToDo
		if ($this->_temp_tarname != '') {
			@unlink($this->_temp_tarname);
			$this->_temp_tarname = '';
		}

		return true;
	}

	private function _cleanFile()
	{
		$this->_close();

		// ----- Look for a local copy
		if ($this->_temp_tarname != '') {
			// ----- Remove the local copy but not the remote tarname
			@unlink($this->_temp_tarname);
			$this->_temp_tarname = '';
		} else {
			// ----- Remove the local tarname file
			@unlink($this->_tarname);
		}
		$this->_tarname = '';

		return true;
	}

	private function _readBlock()
	{
		$v_block = null;
		if (is_resource($this->_file)) {
			$v_block = @fread($this->_file, 512);
		}
		return $v_block;
	}

	private function _jumpBlock($p_len = null)
	{
		if (is_resource($this->_file)) {
			if ($p_len === null) {
				$p_len = 1;
			}

			@fseek($this->_file, @ftell($this->_file) + ($p_len * 512));
		}
		return true;
	}

	private function _readHeader($v_binary_data, &$v_header)
	{
		if (strlen($v_binary_data) == 0) {
			$v_header['filename'] = '';
			return true;
		}

		if (strlen($v_binary_data) != 512) {
			$v_header['filename'] = '';
			$this->_error('Invalid block size : ' . strlen($v_binary_data));
			return false;
		}

		// ----- Calculate the checksum
		$v_checksum = 0;
		// ..... First part of the header
		for ($i = 0; $i < 148; $i++) {
			$v_checksum += ord(substr($v_binary_data, $i, 1));
		}
		// ..... Ignore the checksum value and replace it by ' ' (space)
		for ($i = 148; $i < 156; $i++) {
			$v_checksum += ord(' ');
		}
		// ..... Last part of the header
		for ($i = 156; $i < 512; $i++) {
			$v_checksum += ord(substr($v_binary_data, $i, 1));
		}

		$v_data = unpack(
			"a100filename/a8mode/a8uid/a8gid/a12size/a12mtime/"
						 . "a8checksum/a1typeflag/a100link/a6magic/a2version/"
						 . "a32uname/a32gname/a8devmajor/a8devminor",
			$v_binary_data
		);

		// ----- Extract the checksum
		$v_header['checksum'] = OctDec(trim($v_data['checksum']));
		if ($v_header['checksum'] != $v_checksum) {
			$v_header['filename'] = '';

			// ----- Look for last block (empty block)
			if (($v_checksum == 256) && ($v_header['checksum'] == 0)) {
				return true;
			}

			$this->_error('Invalid checksum for file "' . $v_data['filename']
						  . '" : ' . $v_checksum . ' calculated, '
						  . $v_header['checksum'] . ' expected');
			return false;
		}

		// ----- Extract the properties
		$v_header['filename'] = trim($v_data['filename']);
		$v_header['mode'] = OctDec(trim($v_data['mode']));
		$v_header['uid'] = OctDec(trim($v_data['uid']));
		$v_header['gid'] = OctDec(trim($v_data['gid']));
		$v_header['size'] = OctDec(trim($v_data['size']));
		$v_header['mtime'] = OctDec(trim($v_data['mtime']));
		if (($v_header['typeflag'] = $v_data['typeflag']) == "5") {
			$v_header['size'] = 0;
		}
		return true;
	}

	private function _readLongHeader(&$v_header)
	{
		$v_filename = '';
		$n = floor($v_header['size'] / 512);
		for ($i = 0; $i < $n; $i++) {
			$v_content = $this->_readBlock();
			$v_filename .= $v_content;
		}
		if (($v_header['size'] % 512) != 0) {
			$v_content = $this->_readBlock();
			$v_filename .= $v_content;
		}

		// ----- Read the next header
		$v_binary_data = $this->_readBlock();

		if (!$this->_readHeader($v_binary_data, $v_header)) {
			return false;
		}

		$v_header['filename'] = $v_filename;

		return true;
	}

	protected function _extractList(
		$p_path,
		&$p_list_detail,
		$p_mode,
		$p_file_list,
		$p_remove_path
	) {
		$v_result = true;
		$v_nb = 0;
		$v_extract_all = true;
		$v_listing = false;

		$p_path = $this->_translateWinPath($p_path, false);
		if ($p_path == '' || (substr($p_path, 0, 1) != '/'
		&& substr($p_path, 0, 3) != "../" && !strpos($p_path, ':'))) {
			$p_path = "./" . $p_path;
		}
		$p_remove_path = $this->_translateWinPath($p_remove_path);

		// ----- Look for path to remove format (should end by /)
		if (($p_remove_path != '') && (substr($p_remove_path, -1) != '/')) {
			$p_remove_path .= '/';
		}
		$p_remove_path_size = strlen($p_remove_path);

		switch ($p_mode) {
	  case "complete":
		$v_extract_all = true;
		$v_listing = false;
	  break;
	  case "partial":
		  $v_extract_all = false;
		  $v_listing = false;
	  break;
	  case "list":
		  $v_extract_all = false;
		  $v_listing = true;
	  break;
	  default:
		$this->_error('Invalid extract mode (' . $p_mode . ')');
		return false;
	}

		clearstatcache();

		while (strlen($v_binary_data = $this->_readBlock()) != 0) {
			$v_extract_file = false;
			$v_extraction_stopped = 0;

			if (!$this->_readHeader($v_binary_data, $v_header)) {
				return false;
			}

			if ($v_header['filename'] == '') {
				continue;
			}

			// ----- Look for long filename
			if ($v_header['typeflag'] == 'L') {
				if (!$this->_readLongHeader($v_header)) {
					return false;
				}
			}

			if ((!$v_extract_all) && (is_array($p_file_list))) {
				// ----- By default no unzip if the file is not found
				$v_extract_file = false;

				$p_file_list_count = count($p_file_list);
				for ($i = 0; $i < $p_file_list_count; $i++) {
					// ----- Look if it is a directory
					if (substr($p_file_list[$i], -1) == '/') {
						// ----- Look if the directory is in the filename path
						if ((strlen($v_header['filename']) > strlen($p_file_list[$i]))
				&& (substr($v_header['filename'], 0, strlen($p_file_list[$i]))
					== $p_file_list[$i])) {
							$v_extract_file = true;
							break;
						}
					}

					// ----- It is a file, so compare the file names
					elseif ($p_file_list[$i] == $v_header['filename']) {
						$v_extract_file = true;
						break;
					}
				}
			} else {
				$v_extract_file = true;
			}

			// ----- Look if this file need to be extracted
			if (($v_extract_file) && (!$v_listing)) {
				if (($p_remove_path != '')
			&& (substr($v_header['filename'], 0, $p_remove_path_size)
				== $p_remove_path)) {
					$v_header['filename'] = substr(
						$v_header['filename'],
						$p_remove_path_size
					);
				}
				if (($p_path != './') && ($p_path != '/')) {
					while (substr($p_path, -1) == '/') {
						$p_path = substr($p_path, 0, strlen($p_path) - 1);
					}

					if (substr($v_header['filename'], 0, 1) == '/') {
						$v_header['filename'] = $p_path . $v_header['filename'];
					} else {
						$v_header['filename'] = $p_path . '/' . $v_header['filename'];
					}
				}
				if (file_exists($v_header['filename'])) {
					if ((@is_dir($v_header['filename']))
			  && ($v_header['typeflag'] == '')) {
						$this->_error('File ' . $v_header['filename']
						  . ' already exists as a directory');
						return false;
					}
					if (($this->_isArchive($v_header['filename']))
			  && ($v_header['typeflag'] == "5")) {
						$this->_error('Directory ' . $v_header['filename']
						  . ' already exists as a file');
						return false;
					}
					if (!is_writable($v_header['filename'])) {
						$this->_error('File ' . $v_header['filename']
						  . ' already exists and is write protected');
						return false;
					}
					if (filemtime($v_header['filename']) > $v_header['mtime']) {
						// To be completed : An error or silent no replace ?
					}
				}

				// ----- Check the directory availability and create it if necessary
				elseif (($v_result
				 = $this->_dirCheck(($v_header['typeflag'] == "5"
									? $v_header['filename']
									: dirname($v_header['filename'])))) != 1) {
					$this->_error('Unable to create path for ' . $v_header['filename']);
					return false;
				}

				if ($v_extract_file) {
					if ($v_header['typeflag'] == "5") {
						if (!@file_exists($v_header['filename'])) {
							if (!@mkdir($v_header['filename'], Prado::getDefaultPermissions())) {
								$this->_error('Unable to create directory {'
								  . $v_header['filename'] . '}');
								return false;
							}
							chmod($v_header['filename'], Prado::getDefaultPermissions());
						}
					} else {
						if (($v_dest_file = @fopen($v_header['filename'], "wb")) == 0) {
							$this->_error('Error while opening {' . $v_header['filename']
								. '} in write binary mode');
							return false;
						} else {
							$n = floor($v_header['size'] / 512);
							for ($i = 0; $i < $n; $i++) {
								$v_content = $this->_readBlock();
								fwrite($v_dest_file, $v_content, 512);
							}
							if (($v_header['size'] % 512) != 0) {
								$v_content = $this->_readBlock();
								fwrite($v_dest_file, $v_content, ($v_header['size'] % 512));
							}

							@fclose($v_dest_file);

							// ----- Change the file mode, mtime
							@touch($v_header['filename'], $v_header['mtime']);
							// To be completed
			//chmod($v_header[filename], DecOct($v_header[mode]));
						}

						// ----- Check the file size
						clearstatcache();
						if (filesize($v_header['filename']) != $v_header['size']) {
							$this->_error('Extracted file ' . $v_header['filename']
							. ' does not have the correct file size \''
							. filesize($v_header['filename'])
							. '\' (' . $v_header['size']
							. ' expected). Archive may be corrupted.');
							return false;
						}
					}
				} else {
					$this->_jumpBlock(ceil(($v_header['size'] / 512)));
				}
			} else {
				$this->_jumpBlock(ceil(($v_header['size'] / 512)));
			}

			/* TBC : Seems to be unused ...
			if ($this->_compress)
		$v_end_of_file = @gzeof($this->_file);
			else
		$v_end_of_file = @feof($this->_file);
		*/

			if ($v_listing || $v_extract_file || $v_extraction_stopped) {
				// ----- Log extracted files
				if (($v_file_dir = dirname($v_header['filename']))
			== $v_header['filename']) {
					$v_file_dir = '';
				}
				if ((substr($v_header['filename'], 0, 1) == '/') && ($v_file_dir == '')) {
					$v_file_dir = '/';
				}

				$p_list_detail[$v_nb++] = $v_header;
			}
		}

		return true;
	}

	/**
	 * Check if a directory exists and create it (including parent
	 * dirs) if not.
	 *
	 * @param string $p_dir directory to check
	 *
	 * @return bool true if the directory exists or was created
	 */
	protected function _dirCheck($p_dir)
	{
		if ((@is_dir($p_dir)) || ($p_dir == '')) {
			return true;
		}

		$p_parent_dir = dirname($p_dir);

		if (($p_parent_dir != $p_dir) &&
			($p_parent_dir != '') &&
			(!$this->_dirCheck($p_parent_dir))) {
			return false;
		}

		if (!@mkdir($p_dir, Prado::getDefaultPermissions())) {
			$this->_error("Unable to create directory '$p_dir'");
			return false;
		}
		chmod($p_dir, Prado::getDefaultPermissions());

		return true;
	}

	protected function _translateWinPath($p_path, $p_remove_disk_letter = true)
	{
		if (substr(PHP_OS, 0, 3) == 'WIN') {
			// ----- Look for potential disk letter
			if (($p_remove_disk_letter)
			  && (($v_position = strpos($p_path, ':')) != false)) {
				$p_path = substr($p_path, $v_position + 1);
			}
			// ----- Change potential windows directory separator
			if ((strpos($p_path, '\\') > 0) || (substr($p_path, 0, 1) == '\\')) {
				$p_path = strtr($p_path, '\\', '/');
			}
		}
		return $p_path;
	}
}