<?php
require_once("debug.php");

define (DP_EMPTY, 0 );
define (DP_STRING_SOURCE, 1 );
define (DP_FILE_SOURCE, 2 );

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

class ExcelParserUtil
{
/**
* @param string $str
* @return long
* @deprecated
* @since 4.0.3
*/
function str2long($str)
{
$res=ord($str[0]) + 256*(ord($str[1]) + 256*(ord($str[2]) + 256*(ord($str[3]))));
// $res=ord($str[0]) + 0x100*ord($str[1]) + 0x10000*ord($str[2]) + 0x1000000*ord($str[3]);
// $res=ord($str[0]) + ((ord($str[1])) << 8) + ((ord($str[2])) << 16) + ((ord($str[3])) << 24);
return $res;
}
}

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

class DataProvider
{
/**
* Set type of data:
* DP_FILE_SOURCE
* DP_STRING_SOURCE
* DP_EMPTY
*
* @param string
* @param int
*/
function DataProvider ($data, $dataType)
{
switch( $dataType )
{
case DP_FILE_SOURCE:
if( !( $this->_data = @fopen( $data, "rb" )) )
return;
$this->_size = @filesize( $data );
if( !$this->_size )
_die("Failed to determine file size.");
break;
case DP_STRING_SOURCE:
$this->_data = $data;
$this->_size = strlen( $data );
break;
default:
_die("Invalid data type provided.");
}

$this->_type = $dataType;
register_shutdown_function( array( $this, "close") );
}

/**
* Get data from $offset
*
* @param int $offset
* @param int $length
* @return mixed
*/
function get ($offset, $length)
{
if( !$this->isValid() )
_die("Data provider is empty.");
if( $this->_baseOfs + $offset + $length > $this->_size )
_die("Invalid offset/length.");

switch( $this->_type )
{
case DP_FILE_SOURCE:
{
if( @fseek( $this->_data, $this->_baseOfs + $offset, SEEK_SET ) == -1 )
_die("Failed to seek file position specified by offest.");
return @fread( $this->_data, $length );
}
case DP_STRING_SOURCE:
{
$rc = substr( $this->_data, $this->_baseOfs + $offset, $length );
return $rc;
}
default:
_die("Invalid data type or class was not initialized.");
}
}

/**
* @param int $offset
* @return int
*/
function getByte($offset)
{
return $this->get($offset, 1 );
}

/**
* @param int $offset
* @return int
*/
function getOrd( $offset )
{
return ord( $this->getByte( $offset ) );
}

/**
* Returns longint from $offset
* @param int $offset
* @return int
*/
function getLong( $offset )
{
$str = $this->get( $offset, 4 );
return ExcelParserUtil::str2long( $str );
// return (int) $str;
}

/**
* @return int
*/
function getSize()
{
if( !$this->isValid() )
_die("Data provider is empty.");
return $this->_size;
}

/**
* Return quantity of 0x200 blocks
* @return int
*/
function getBlocks()
{
if( !$this->isValid() )
_die("Data provider is empty.");
return (int)(($this->_size - 1) / 0x200) - 1;
}

/**
* @param array
* @param int
* @return string
*/

function ReadFromFat( $chain, $gran = 0x200 )
{
$rc = '';
for( $i = 0; $i < count($chain); $i++ )
$rc .= $this->get( $chain[$i] * $gran, $gran );
return $rc;
}

function close()
{
switch($this->_type )
{
case DP_FILE_SOURCE:
@fclose( $this->_data );
case DP_STRING_SOURCE:
$this->_data = null;
default:
$_type = DP_EMPTY;
break;
}
}

/**
* @return bool
*/
function isValid()
{
return $this->_type != DP_EMPTY;
}
/**
* @var int
*/
var $_type = DP_EMPTY;
/**
* @var mixed
*/
var $_data = null;
/**
* @var int
*/
var $_size = -1;
/**
* @var int
*/
var $_baseOfs = 0;
}

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

?>