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

class PDF_EAN13 extends FPDF
{
function EAN13($x, $y, $barcode, $h=16, $w=.35)
{
	$this->Barcode($x,$y,$barcode,$h,$w,13);
}

function UPC_A($x, $y, $barcode, $h=16, $w=.35)
{
	$this->Barcode($x,$y,$barcode,$h,$w,12);
}

function GetCheckDigit($barcode)
{
	//Compute the check digit
	$sum=0;
	for($i=1;$i<=11;$i+=2)
		$sum+=3*$barcode[$i];
	for($i=0;$i<=10;$i+=2)
		$sum+=$barcode[$i];
	$r=$sum%10;
	if($r>0)
		$r=10-$r;
	return $r;
}

function TestCheckDigit($barcode)
{
	//Test validity of check digit
	$sum=0;
	for($i=1;$i<=11;$i+=2)
		$sum+=3*$barcode[$i];
	for($i=0;$i<=10;$i+=2)
		$sum+=$barcode[$i];
	return ($sum+$barcode[12])%10==0;
}

function Barcode($x, $y, $barcode, $h, $w, $len)
{
	//Padding
	$barcode=str_pad($barcode,$len-1,'0',STR_PAD_LEFT);
	if($len==12)
		$barcode='0'.$barcode;
	//Add or control the check digit
	if(strlen($barcode)==12)
		$barcode.=$this->GetCheckDigit($barcode);
	elseif(!$this->TestCheckDigit($barcode))
		$this->Error('Incorrect check digit');
	//Convert digits to bars
	$codes=array(
		'A'=>array(
			'0'=>'0001101','1'=>'0011001','2'=>'0010011','3'=>'0111101','4'=>'0100011',
			'5'=>'0110001','6'=>'0101111','7'=>'0111011','8'=>'0110111','9'=>'0001011'),
		'B'=>array(
			'0'=>'0100111','1'=>'0110011','2'=>'0011011','3'=>'0100001','4'=>'0011101',
			'5'=>'0111001','6'=>'0000101','7'=>'0010001','8'=>'0001001','9'=>'0010111'),
		'C'=>array(
			'0'=>'1110010','1'=>'1100110','2'=>'1101100','3'=>'1000010','4'=>'1011100',
			'5'=>'1001110','6'=>'1010000','7'=>'1000100','8'=>'1001000','9'=>'1110100')
		);
	$parities=array(
		'0'=>array('A','A','A','A','A','A'),
		'1'=>array('A','A','B','A','B','B'),
		'2'=>array('A','A','B','B','A','B'),
		'3'=>array('A','A','B','B','B','A'),
		'4'=>array('A','B','A','A','B','B'),
		'5'=>array('A','B','B','A','A','B'),
		'6'=>array('A','B','B','B','A','A'),
		'7'=>array('A','B','A','B','A','B'),
		'8'=>array('A','B','A','B','B','A'),
		'9'=>array('A','B','B','A','B','A')
		);
	$code='101';
	$p=$parities[$barcode[0]];
	for($i=1;$i<=6;$i++)
		$code.=$codes[$p[$i-1]][$barcode[$i]];
	$code.='01010';
	for($i=7;$i<=12;$i++)
		$code.=$codes['C'][$barcode[$i]];
	$code.='101';
	//Draw bars
	for($i=0;$i<strlen($code);$i++)
	{
		if($code[$i]=='1')
			$this->Rect($x+$i*$w,$y,$w,$h,'F');
	}
	//Print text uder barcode
	$this->SetFont('Arial','',12);
	$this->Text($x,$y+$h+11/$this->k,substr($barcode,-$len));
}
}
?>