/*
	Memory optimization

	Informations
	Author: Olivier
	License: Freeware

	Description
	The standard FPDF class builds the document entirely in memory,
	which can be problematic for large documents.
	This extension saves the pages to the destination file as soon as they are finished,
	which solves the memory issue.
 
	After you have created the object, call Open() with the name of the file:

	$pdf=new FPDF2File();
	$pdf->Open('doc.pdf');

	and when the document is finished, call Output():
	$pdf->Output();

	Note: you can't use the AliasNbPages() method with this extension.
*/

<?php
require('fpdf.php');

class FPDF2File extends FPDF
{
var $f;

function Open($file)
{
	if(FPDF_VERSION<'1.53')
		$this->Error('Version 1.53 or above is required by this extension');
	$this->f=fopen($file,'wb');
	if(!$this->f)
		$this->Error('Unable to create output file: '.$file);
	parent::Open();
	$this->_putheader();
}

function Image($file,$x,$y,$w=0,$h=0,$type='',$link='')
{
	if(!isset($this->images[$file]))
	{
		//Retrieve only meta-information
		$a=getimagesize($file);
		if($a===false)
			$this->Error('Missing or incorrect image file: '.$file);
		$this->images[$file]=array('w'=>$a[0],'h'=>$a[1],'type'=>$a[2],'i'=>count($this->images)+1);
	}
	parent::Image($file,$x,$y,$w,$h,$type,$link);
}

function Output()
{
	if($this->state<3)
		$this->Close();
}

function _endpage()
{
	parent::_endpage();
	//Write page to file
	$filter=($this->compress) ? '/Filter /FlateDecode ' : '';
	$p=($this->compress) ? gzcompress($this->buffer) : $this->buffer;
	$this->_newobj();
	$this->_out('<<'.$filter.'/Length '.strlen($p).'>>');
	$this->_putstream($p);
	$this->_out('endobj');
	$this->buffer='';
}

function _newobj()
{
	$this->n++;
	$this->offsets[$this->n]=ftell($this->f);
	$this->_out($this->n.' 0 obj');
}

function _out($s)
{
	if($this->state==2)
		$this->buffer.=$s."\n";
	else
		fwrite($this->f,$s."\n",strlen($s)+1);
}

function _putimages()
{
	$mqr=get_magic_quotes_runtime();
	set_magic_quotes_runtime(0);
	$filter=($this->compress) ? '/Filter /FlateDecode ' : '';
	reset($this->images);
	while(list($file,$info)=each($this->images))
	{
		//Load image
		if($info['type']==2)
			$info=$this->_parsejpg($file);
		elseif($info['type']==3)
			$info=$this->_parsepng($file);
		elseif($info['type']==1 && method_exists($this,'_parsegif'))
			$info=$this->_parsegif($file);
		else
			$this->Error('Unsupported image type: '.$file);
		//Put it into file
		$this->_newobj();
		$this->images[$file]['n']=$this->n;
		$this->_out('<</Type /XObject');
		$this->_out('/Subtype /Image');
		$this->_out('/Width '.$info['w']);
		$this->_out('/Height '.$info['h']);
		if($info['cs']=='Indexed')
			$this->_out('/ColorSpace [/Indexed /DeviceRGB '.(strlen($info['pal'])/3-1).' '.($this->n+1).' 0 R]');
		else
		{
			$this->_out('/ColorSpace /'.$info['cs']);
			if($info['cs']=='DeviceCMYK')
				$this->_out('/Decode [1 0 1 0 1 0 1 0]');
		}
		$this->_out('/BitsPerComponent '.$info['bpc']);
		if(isset($info['f']))
			$this->_out('/Filter /'.$info['f']);
		if(isset($info['parms']))
			$this->_out($info['parms']);
		if(isset($info['trns']) && is_array($info['trns']))
		{
			$trns='';
			for($i=0;$i<count($info['trns']);$i++)
				$trns.=$info['trns'][$i].' '.$info['trns'][$i].' ';
			$this->_out('/Mask ['.$trns.']');
		}
		$this->_out('/Length '.strlen($info['data']).'>>');
		$this->_putstream($info['data']);
		unset($info['data']);
		$this->_out('endobj');
		//Palette
		if($info['cs']=='Indexed')
		{
			$this->_newobj();
			$pal=($this->compress) ? gzcompress($info['pal']) : $info['pal'];
			$this->_out('<<'.$filter.'/Length '.strlen($pal).'>>');
			$this->_putstream($pal);
			$this->_out('endobj');
		}
	}
	set_magic_quotes_runtime($mqr);
}

function _putpages()
{
	$nb=$this->page;
	if($this->DefOrientation=='P')
	{
		$wPt=$this->fwPt;
		$hPt=$this->fhPt;
	}
	else
	{
		$wPt=$this->fhPt;
		$hPt=$this->fwPt;
	}
	//Page objects
	for($n=1;$n<=$nb;$n++)
	{
		$this->_newobj();
		$this->_out('<</Type /Page');
		$this->_out('/Parent 1 0 R');
		if(isset($this->OrientationChanges[$n]))
			$this->_out(sprintf('/MediaBox [0 0 %.2f %.2f]',$hPt,$wPt));
		$this->_out('/Resources 2 0 R');
		if(isset($this->PageLinks[$n]))
		{
			//Links
			$annots='/Annots [';
			foreach($this->PageLinks[$n] as $pl)
			{
				$rect=sprintf('%.2f %.2f %.2f %.2f',$pl[0],$pl[1],$pl[0]+$pl[2],$pl[1]-$pl[3]);
				$annots.='<</Type /Annot /Subtype /Link /Rect ['.$rect.'] /Border [0 0 0] ';
				if(is_string($pl[4]))
					$annots.='/A <</S /URI /URI '.$this->_textstring($pl[4]).'>>>>';
				else
				{
					$l=$this->links[$pl[4]];
					$h=isset($this->OrientationChanges[$l[0]]) ? $wPt : $hPt;
					$annots.=sprintf('/Dest [%d 0 R /XYZ 0 %.2f null]>>',2+$nb+$l[0],$h-$l[1]*$this->k);
				}
			}
			$this->_out($annots.']');
		}
		$this->_out('/Contents '.(2+$n).' 0 R>>');
		$this->_out('endobj');
	}
	//Page root
	$this->offsets[1]=ftell($this->f);
	$this->_out('1 0 obj');
	$this->_out('<</Type /Pages');
	$kids='/Kids [';
	for($n=1;$n<=$nb;$n++)
		$kids.=(2+$nb+$n).' 0 R ';
	$this->_out($kids.']');
	$this->_out('/Count '.$nb);
	$this->_out(sprintf('/MediaBox [0 0 %.2f %.2f]',$wPt,$hPt));
	$this->_out('>>');
	$this->_out('endobj');
}

function _putresources()
{
	$this->_putfonts();
	$this->_putimages();
	//Resource dictionary
	$this->offsets[2]=ftell($this->f);
	$this->_out('2 0 obj');
	$this->_out('<<');
	$this->_putresourcedict();
	$this->_out('>>');
	$this->_out('endobj');
}

function _putcatalog()
{
	$this->_out('/Type /Catalog');
	$this->_out('/Pages 1 0 R');
	$n=3+$this->page;
	if($this->ZoomMode=='fullpage')
		$this->_out('/OpenAction ['.$n.' 0 R /Fit]');
	elseif($this->ZoomMode=='fullwidth')
		$this->_out('/OpenAction ['.$n.' 0 R /FitH null]');
	elseif($this->ZoomMode=='real')
		$this->_out('/OpenAction ['.$n.' 0 R /XYZ null null 1]');
	elseif(!is_string($this->ZoomMode))
		$this->_out('/OpenAction ['.$n.' 0 R /XYZ null null '.($this->ZoomMode/100).']');
	if($this->LayoutMode=='single')
		$this->_out('/PageLayout /SinglePage');
	elseif($this->LayoutMode=='continuous')
		$this->_out('/PageLayout /OneColumn');
	elseif($this->LayoutMode=='two')
		$this->_out('/PageLayout /TwoColumnLeft');
}

function _enddoc()
{
	$this->_putpages();
	$this->_putresources();
	//Info
	$this->_newobj();
	$this->_out('<<');
	$this->_putinfo();
	$this->_out('>>');
	$this->_out('endobj');
	//Catalog
	$this->_newobj();
	$this->_out('<<');
	$this->_putcatalog();
	$this->_out('>>');
	$this->_out('endobj');
	//Cross-ref
	$o=ftell($this->f);
	$this->_out('xref');
	$this->_out('0 '.($this->n+1));
	$this->_out('0000000000 65535 f ');
	for($i=1;$i<=$this->n;$i++)
		$this->_out(sprintf('%010d 00000 n ',$this->offsets[$i]));
	//Trailer
	$this->_out('trailer');
	$this->_out('<<');
	$this->_puttrailer();
	$this->_out('>>');
	$this->_out('startxref');
	$this->_out($o);
	$this->_out('%%EOF');
	$this->state=3;
	fclose($this->f);
}
}