From f332fd68faebf377959630b569639bad620785b2 Mon Sep 17 00:00:00 2001
From: Richard Wolsch <coding@richardwolsch.de>
Date: Mon, 6 Sep 2021 09:49:10 +0200
Subject: [PATCH] Add support for checkboxes which are organized as children
 (/Kids) of parent form elements.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

new:
- set the checkbox value in child AND parent
- remove checkbox parent object IDs from /Fields definition (otherwise they will not display their value correctly due to /NeedAppearances – which itself is needed to display the value of text inputs correctly)
---
 src/fpdm.php | 960 +++++++++++++++++++++++++++------------------------
 1 file changed, 504 insertions(+), 456 deletions(-)

diff --git a/src/fpdm.php b/src/fpdm.php
index fb8627d..7a36aaf 100644
--- a/src/fpdm.php
+++ b/src/fpdm.php
@@ -26,7 +26,7 @@
 *	stream core	with advanced verbose output. Fix() bonus for corrupted pdfs.  *
 *	V2.3 (28.11.2010) stream type was lost when /length defined after /Filter  *
 *	V2.2 (27.11.2010) Stream filter improved:decode now handles multi filters! *                                                      *
-*	V2.1 (25.11.2010) Only filter support for streams, trailer detection was   * 
+*	V2.1 (25.11.2010) Only filter support for streams, trailer detection was   *
 *	too restrictive. fixes FDF error occuring when empty array data is given.  *
 *   V2.0 (05.11.2010) Load support for inline text fields datas or FDF content *
 *	V1.1 (04.11.2010) Works now under php4 for backward compat.                *
@@ -36,6 +36,7 @@
 global $FPDM_FILTERS, $FPDM_REGEXPS; //needs explicit global scope, otherwise autoloading will be incomplete.
 $FPDM_FILTERS=array(); //holds all supported filters
 $FPDM_REGEXPS= array(
+    "/Parent" => "/\/Parent\s+(\d+)\s(\d+)\sR$/",
 	//FIX: parse checkbox definition
 	"/AS"=>"/\/AS\s+\/(\w+)$/",
 	"name"=>"/\/(\w+)/",
@@ -58,61 +59,61 @@
 
 $__tmp = version_compare(phpversion(), "5") == -1 ? array('FPDM') : array('FPDM', false);
 if (!call_user_func_array('class_exists', $__tmp)) {
-    
-	
-	define('FPDM_VERSION',2.9); 
-	
+
+
+	define('FPDM_VERSION',2.9);
+
 	define('FPDM_INVALID',0);
 	define('FPDM_STATIC',1);
 	define('FPDM_COMMON',2);
 	define('FPDM_VERBOSE',3);
 	define('FPDM_CACHE',dirname(__FILE__).'/export/cache/'); //cache directory for fdf temporary files needed by pdftk.
 	define('FPDM_PASSWORD_MAX_LEN',15); //Security to prevent shell overflow.
-	
+
     class FPDM {
     //@@@@@@@@@
 		var $useCheckboxParser = false;      //boolean: allows activation of custom checkbox parser (not available in original FPDM source)
 
 		var $pdf_source = '';      //string: full pathname to the input pdf , a form file
 		var $fdf_source = '';	  //string: full pathname to the input fdf , a form data file
-		var $pdf_output = '';      //string: full pathname to the resulting filled pdf 
-		
+		var $pdf_output = '';      //string: full pathname to the resulting filled pdf
+
 		var $pdf_entries = array();     //array: Holds the content of the pdf file as array
 		var $fdf_content = '';     //string: holds the content of the fdf file
-		var $fdf_parse_needed = false;//boolean: false will use $fields data else extract data from fdf content 
-		var $value_entries = array();   //array: a map of values to faliclitate access and changes 
-		
+		var $fdf_parse_needed = false;//boolean: false will use $fields data else extract data from fdf content
+		var $value_entries = array();   //array: a map of values to faliclitate access and changes
+
 		var $positions = array(); 	  //array, stores what object id is at a given position n ($positions[n]=<obj_id>)
-		
+
 		var $offsets = array();   	  //array of offsets for objects, index is the object's id, starting at 1
-		var $pointer = 0;   	  //integer, Current line position in the pdf file during the parsing 
-		
+		var $pointer = 0;   	  //integer, Current line position in the pdf file during the parsing
+
 		var $shifts = array();    	  //array, Shifts of objects in the order positions they appear in the pdf, starting at 0.
 		var $shift = 0;     	  //integer, Global shift file size due to object values size changes
-		
+
 		var $streams = '';         //Holds streams configuration found during parsing
 		var $streams_filter = '';  //Regexp to decode filter streams
-		
+
 		var $safe_mode = false;       //boolean, if set, ignore previous offsets do no calculations for the new xref table, seek pos directly in file
 		var $check_mode = false;      //boolean, Use this to track offset calculations errors in corrupteds pdfs files for sample
 		var $halt_mode = false; 	  //if true, stops when offset error is encountered
-		
+
 		var $info = array(); 			  //array, holds the info properties
 		var $fields = array(); 		  //array that holds fields-Data parsed from FDF
-		
-		var $verbose = false;         //boolean ,  a debug flag to decide whether or not to show internal process 
+
+		var $verbose = false;         //boolean ,  a debug flag to decide whether or not to show internal process
 		var $verbose_level = 1;   //integer default is 1 and if greater than 3, shows internal parsing as well
-		
+
 		var $support = ''; 		  //string set to 'native' for fpdm or 'pdftk' for pdf toolkit
 		var $flatten_mode = false;	  //if true, flatten field data as text and remove form fields (NOT YET SUPPORTED BY FPDM)
 		var $compress_mode = false;   //boolean , pdftk feature only to compress streams
 		var $uncompress_mode = false; //boolean pdftk feature only to uncompress streams
-		var $security = array();        //Array holding securtity settings  
+		var $security = array();        //Array holding securtity settings
 							  //(password owner nad user,  encrypt (set to 40 or 128 or 0), allow <permissions>] see pdfk help
 
 		var $needAppearancesTrue = false;	//boolean, indicates if /NeedAppearances is already set to true
 		var $isUTF8 = false;				//boolean (true for UTF-8, false for ISO-8859-1)
-		
+
         /**
          * Constructor
          *
@@ -121,68 +122,68 @@ class FPDM {
 		 *@param string $fdf_source Source-Filename
 		 *@param boolean $verbose , optional false per default
          */
-    	function __construct() { 
+    	function __construct() {
 		//==============
-		
+
 			$args=func_get_args();
 			$num_args=func_num_args();
-			
+
 			$FDF_FILE=($num_args>=FPDM_COMMON);
 			$VERBOSE_FLAG=($num_args>=FPDM_VERBOSE);
-			
+
 			$verbose=false;
-			
+
 			//We are not joking here, let's have a polymorphic constructor!
 			switch($num_args) {
 				case FPDM_INVALID:
 					$this->Error("Invalid instantiation of FPDM, requires at least one param");
 					break;
-				case FPDM_STATIC: 
-					if($args[0] =='[_STATIC_]')  break; //static use, caller is anonymous function defined in _set_field_value 
+				case FPDM_STATIC:
+					if($args[0] =='[_STATIC_]')  break; //static use, caller is anonymous function defined in _set_field_value
 					//else this is the pdf_source then, fdf content is loaded using Load() function
 				default:
 				case FPDM_VERBOSE: //Use the verbose value provided
 					if($VERBOSE_FLAG) $verbose=$args[2];
 				case FPDM_COMMON: //Common use
 					$this->pdf_source = $args[0];//Blank pdf form
-					
+
 					if($FDF_FILE) {
 						$this->fdf_source = $args[1];//Holds the data of the fields to fill the form
-						$this->fdf_parse_needed=true; 
+						$this->fdf_parse_needed=true;
 					}
-					
+
 					//calculation and map
 					$this->offsets=array();
 					$this->pointer=0;
 					$this->shift=0;
 					$this->shifts=array();
 					$this->n=0;
-					
+
 					//Stream filters
 					$filters=$this->getFilters("|");
 					$this->streams_filter="/(\/($filters))+/";
 					//$this->dumpContent($this->streams_filter);
-					
+
 					$this->info=array();
-					
+
 					//Debug modes
 					$this->verbose=$verbose;
-					$this->verbose_level=($verbose&&is_int($verbose)) ? $verbose : 1; 
+					$this->verbose_level=($verbose&&is_int($verbose)) ? $verbose : 1;
 					$this->safe_mode=false;
 					$this->check_mode=false; //script will takes much more time if you do so
 					$this->halt_mode=true;
-					
+
 					$this->support='native'; //may ne overriden
 					$this->security=array('password'=>array('owner'=>null,'user'=>null),'encrypt'=>0,'allow'=>array());
-					
+
 					//echo "<br>filesize:".filesize($this->pdf_source);
 					$this->load_file('PDF');
-					
+
 					if($FDF_FILE) $this->load_file('FDF');
-						
+
 			}
         }
-		
+
 		/**
 		*Loads a form data to be merged
 		*
@@ -195,44 +196,44 @@ function Load($data,$isUTF8=false) {
 			$this->isUTF8 = $isUTF8;
 			$this->load_file('FDF',$data);
 		}
-		
+
 		/**
 		*Loads a file according to its type
 		*
 		*@access private
 		*@param string type 'PDF' or 'FDF'
-		*@param String|array content the data content of FDF files only or directly the fields values as array 
+		*@param String|array content the data content of FDF files only or directly the fields values as array
 		**/
 		function load_file($type,$content=NULL) {
 		//------------------------------------
 			 switch($type) {
-				case "PDF" : 
+				case "PDF" :
 					if($content)
 						$this->Error("load_file do not accept PDF content, only FDF content sorry");
 					else
 						$this->pdf_entries = $this->getEntries($this->pdf_source,'PDF');
 				break;
-				case "FDF" : 
+				case "FDF" :
 					if(!is_null($content)) {
 						if(is_array($content)) {
 							$this->fields=$content;
 							$this->fdf_parse_needed=false;
 							//$this->dumpEntries($content,"PDF fields content");
 						} else if(is_string($content)){ //String
-							$this->fdf_content = $content; //TODO: check content 
-							$this->fdf_parse_needed=true; 
+							$this->fdf_content = $content; //TODO: check content
+							$this->fdf_parse_needed=true;
 						} else
 							$this->Error('Invalid content type for this FDF file!');
 					} else {
 						$this->fdf_content = $this->getContent($this->fdf_source,'FDF');
-						$this->fdf_parse_needed=true; 
+						$this->fdf_parse_needed=true;
 					}
 				break;
 				default:
 					$this->Error("Invalid file type $type");
 			}
 		}
-		
+
 		/**
 		*Set a mode and play with your power debug toys
 		*
@@ -274,13 +275,13 @@ function set_modes($mode,$value) {
 					$this->Error("set_modes error, Invalid mode '<i>$mode</i>'");
 			}
 		}
-		
+
 		/**
 		*Retrieves informations of the pdf
 		*
-		*@access public 
+		*@access public
 		*@note To track PDF versions and so on...
-		*@param Boolean output	
+		*@param Boolean output
 		**/
 		function Info($asArray=false) {
 		//----------------------
@@ -303,14 +304,14 @@ function Info($asArray=false) {
 				$this->dumpEntries($info);
 			}
 		}
-		
+
 		/**
 		*Changes the support
 		*
-		*@access public 
+		*@access public
 		*@internal fixes xref table offsets
 		*@note special playskool toy for Christmas dedicated to my impatient fanclub (Grant, Kris, nejck,...)
-		*@param String support Allow to use external support that has more advanced features (ie 'pdftk')	
+		*@param String support Allow to use external support that has more advanced features (ie 'pdftk')
 		**/
 		function Plays($cool) {
 		//----------------------
@@ -319,11 +320,11 @@ function Plays($cool) {
 			else
 				$this->support='native';
 		}
-		
+
 		/**
 		*Fixes a corrupted PDF file
 		*
-		*@access public 
+		*@access public
 		*@internal fixes xref table offsets
 		*@note Real work is not made here but by Merge that should be launched after to complete the work
 		**/
@@ -333,26 +334,26 @@ function Fix() {
 			$this->set_modes('check',true); //Compare xref table offsets with objects offsets in the pdf file
 			$this->set_modes('halt',false); //Do no stop on errors so fix is applied during merge process
 		}
-		
+
 		//######## pdftk's output configuration #######
-		
+
 		/**
 		*Decides to use  the  compress filter to restore compression.
-		*@note  This is only useful when you want to repack PDF that was previously edited in a text  editor like vim or emacs.	
+		*@note  This is only useful when you want to repack PDF that was previously edited in a text  editor like vim or emacs.
 		**/
 		function Compress() {
 		//-------------------
-			$this->set_modes('compress',true); 
+			$this->set_modes('compress',true);
 			$this->support="pdftk";
 		}
-		
+
 		/**
 		*Decides to remove PDF page stream compression by applying	the  uncompress  filter.
-		*@note  This is only useful when you want to edit PDF code in a text  editor like vim or emacs.	
+		*@note  This is only useful when you want to edit PDF code in a text  editor like vim or emacs.
 		**/
 		function Uncompress() {
 		//---------------------
-			$this->set_modes('uncompress',true); 
+			$this->set_modes('uncompress',true);
 			$this->support="pdftk";
 		}
 		/**
@@ -360,10 +361,10 @@ function Uncompress() {
 		**/
 		function Flatten() {
 		//-----------------
-			$this->set_modes('flatten',true); 
+			$this->set_modes('flatten',true);
 			$this->support="pdftk";
 		}
-		
+
 		/***
 		*Defines a password type
 		*@param String type , 'owner' or  'user'
@@ -380,8 +381,8 @@ function Password($type,$code) {
 			}
 			$this->support="pdftk";
 		}
-		
-		
+
+
 		/**
 		*Defines the encrytion to the given bits
 		*@param integer $bits 0, 40 or 128
@@ -391,7 +392,7 @@ function Encrypt($bits) {
 			switch($bits) {
 				case 0:
 				case 40:
-				case 128:				
+				case 128:
 				$this->security["encrypt"]=$bits;
 				break;
 				default:
@@ -399,7 +400,7 @@ function Encrypt($bits) {
 			}
 			$this->support="pdftk";
 		}
-		
+
 		/**
 		*Allow permissions
 		*
@@ -460,43 +461,43 @@ function Allow($permissions=null) {
 				$this->support="pdftk";
 			}
 		}
-		
+
 		//#############################
-		
+
 		/**
 		*Merge FDF file with a PDF file
 		*
-		*@access public 
+		*@access public
 		*@note files has been provided during the instantiation of this class
 		*@internal flatten mode is not yet supported
 		*@param Boolean flatten Optional, false by default, if true will use pdftk (requires a shell) to flatten the pdf form
 		**/
 		function Merge($flatten=false) {
 		//------------------------------
-		
+
 			if($flatten) $this->Flatten();
-		
-			
+
+
 			if($this->support == "native") {
-			
+
 				if($this->fdf_parse_needed) {
 					$fields=$this->parseFDFContent();
 				}else {
 					$fields=$this->fields;
 				}
-				
+
 				$count_fields=count($fields);
-				
-				if($this->verbose&&($count_fields==0)) 
+
+				if($this->verbose&&($count_fields==0))
 					$this->dumpContent("The FDF content has either no field data or parsing may failed","FDF parser: ");
-						
+
 				$fields_value_definition_lines=array();
-				
+
 				$count_entries=$this->parsePDFEntries($fields_value_definition_lines);
-			
-			
+
+
 				if($count_entries) {
-				
+
 					$this->value_entries=$fields_value_definition_lines;
 					if($this->verbose) {
 						$this->dumpContent("$count_entries Field entry values found for $count_fields field values to fill","Merge info: ");
@@ -511,21 +512,21 @@ function Merge($flatten=false) {
 						}
 					}
 					//===========================================================
-				
-					//===== Cross refs/size fixes (offsets calculations for objects have been previously be done in set_field_value) ======= 
-					
-					//Update cross reference table to match object size changes 
+
+					//===== Cross refs/size fixes (offsets calculations for objects have been previously be done in set_field_value) =======
+
+					//Update cross reference table to match object size changes
 					$this->fix_xref_table();
-					
+
 					//update the pointer to the cross reference table
 					$this->fix_xref_start();
-					
+
 				}else
 					$this->Error("PDF file is empty!");
-					
+
 			} //else pdftk's job is done in Output, not here.
 		}
-		
+
 		/**
 		*Warns verbose/output conflicts
 		*
@@ -536,7 +537,7 @@ function Close($dest) {
 		//----------------
 			$this->Error("Output: Verbose mode should be desactivated, it is incompatible with this output mode $dest");
 		}
-		
+
 		/**
 		*Get current pdf content (without any offset fixes)
 		*
@@ -554,8 +555,8 @@ function get_buffer($pdf_file=''){
 			}
 			return $buffer;
 		}
-		
-	
+
+
 		/**
 		*Output PDF to some destination
 		*
@@ -566,37 +567,37 @@ function get_buffer($pdf_file=''){
 		**/
 		function Output($dest='', $name=''){
 		//-----------------------------------
-			
+
 			$pdf_file='';
-			
+
 			if($this->support == "pdftk") {
 				//As PDFTK can only merge FDF files not data directly,
 				require_once("lib/url.php"); //we will need a url support because relative urls for pdf inside fdf files are not supported by PDFTK...
-				require_once("export/fdf/fdf.php"); //...conjointly with my patched/bridged forge_fdf that provides fdf file generation support from array data. 
+				require_once("export/fdf/fdf.php"); //...conjointly with my patched/bridged forge_fdf that provides fdf file generation support from array data.
 				require_once("export/pdf/pdftk.php");//Of course don't forget to bridge to PDFTK!
 
 				$tmp_file=false;
 				$pdf_file=resolve_path(fix_path(dirname(__FILE__).'/'.$this->pdf_source));      //string: full pathname to the input pdf , a form file
-				
+
 				if($this->fdf_source) { //FDF file provided
 					$fdf_file=resolve_path(fix_path(dirname(__FILE__).'/'.$this->fdf_source));
 				}else {
-				
+
 					$pdf_url=getUrlfromDir($pdf_file); //Normaly http scheme not local file
-				
+
 					if($this->fdf_parse_needed) { //fdf source was provided
 						$pdf_data=$this->parseFDFContent();
 					}else { //fields data was provided as an array, we have to generate the fdf file
 						$pdf_data=$this->fields;
-					}	
-					
+					}
+
 					$fdf_file=fix_path(FPDM_CACHE)."fields".rnunid().".fdf";
 					$tmp_file=true;
 					$ret=output_fdf($pdf_url,$pdf_data,$fdf_file);
 					if(!$ret["success"])
 						$this->Error("Output failed as something goes wrong (Pdf was $pdf_url) <br> during internal FDF generation of file $fdf_file, <br>Reason is given by {$ret['return']}");
 				}
-				
+
 				//Serializes security options (not deeply tested)
 				$security='';
 				if(!is_null($this->security["password"]["owner"])) $security.=' owner_pw "'.substr($this->security["password"]["owner"],0,FPDM_PASSWORD_MAX_LEN).'"';
@@ -604,31 +605,31 @@ function Output($dest='', $name=''){
 				if($this->security["encrypt"]!=0) $security.=' encrypt_'.$this->security["encrypt"].'bit';
 				if(count($this->security["allow"])>0) {
 					$permissions=$this->security["allow"];
-					$security.=' allow '; 
+					$security.=' allow ';
 					foreach($permissions as $permission)
 						$security.=' '.$permission;
 				}
-				
+
 				//Serialize output modes
 				$output_modes='';
 				if($this->flatten_mode)  $output_modes.=' flatten';
 				if($this->compress_mode) $output_modes.=' compress';
 				if($this->uncompress_mode) $output_modes.=' uncompress';
-		
-				
+
+
 				$ret=pdftk($pdf_file,$fdf_file,array("security"=>$security,"output_modes"=>$output_modes));
-				
+
 				if($tmp_file) @unlink($fdf_file); //Clear cache
-				
+
 				if($ret["success"]) {
 					$pdf_file=$ret["return"];
-				}else 
+				}else
 					$this->Error($ret["return"]);
 			}
-			
+
 			//$this->buffer=$this->get_buffer($pdf_file);
-			
-			
+
+
 			$dest=strtoupper($dest);
 			if($dest=='')
 			{
@@ -640,12 +641,12 @@ function Output($dest='', $name=''){
 				else
 					$dest='F';
 			}
-			
+
 			//Abort to avoid to polluate output
 			if($this->verbose&&(($dest=='I')||($dest=='D'))) {
-				$this->Close($dest); 
+				$this->Close($dest);
 			}
-		
+
 			switch($dest)
 			{
 				case 'I':
@@ -675,7 +676,7 @@ function Output($dest='', $name=''){
 						$this->Error('Some data has already been output, can\'t send PDF file');
 					header('Content-Length: '.strlen($this->get_buffer()));
 					header('Content-Disposition: attachment; filename="'.$name.'"');
-					
+
 					header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // Date in the past
 					header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); // always modified
 					header("Cache-Control: no-store, no-cache, must-revalidate, max-age=0"); // HTTP/1.1
@@ -693,7 +694,7 @@ function Output($dest='', $name=''){
 					$f=fopen($name,'wb');
 					if(!$f)
 						$this->Error('Unable to create output file: '.$name.' (currently opened under Acrobat Reader?)');
-						
+
 					fwrite($f,$this->get_buffer(),strlen($this->get_buffer()));
 					fclose($f);
 					break;
@@ -706,7 +707,7 @@ function Output($dest='', $name=''){
 			return '';
 		}
 
-		
+
 		/**
 		*Decodes and returns the binary form of a field hexified value
 		*
@@ -719,7 +720,7 @@ function pdf_decode_field_value($value) {
 			$call=$this->static_method_call('_hex2bin',$value);
 			return $call;
 		}
-		
+
 		/**
 		*Encodes and returns the headecimal form of a field binary value
 		*
@@ -732,8 +733,8 @@ function pdf_encode_field_value($value) {
 			$value=$this->static_method_call('_bin2hex',$value);
 			return $value;
 		}
-		
-		
+
+
 		/**
 		*Universal Php4/5 static call helper
 		*
@@ -742,14 +743,14 @@ function pdf_encode_field_value($value) {
 		**/
 		function static_method_call($method) {
 		//---------------------------------------------
-	
+
 			$params_call=func_get_args();
 			array_shift($params_call);
 			//var_dump($params_call);
-			
+
 			return call_user_func_array(array($this,$method),$params_call);
 		}
-		
+
 		/**
 		*Changes a field value that can be in hex <> or binary form ()
 		*
@@ -758,21 +759,21 @@ function static_method_call($method) {
 		**/
 		function replace_value($matches,$value) {
 		//----------------------------------------------
-			
+
 			array_shift($matches);
 
 			if(($value!='')&&($matches[1]=="<")) //Value must be hexified..
-				$value=$this->pdf_encode_field_value($value); 
-		
+				$value=$this->pdf_encode_field_value($value);
+
 			$matches[2]=$value;
 			$value_type_code=$matches[0]; //Should be V, DV or TU
 			$matches[0]="/".$value_type_code." ";
-			
+
 			$value=implode("",$matches);
 			//echo(htmlentities($value));
 			return $value;
 		}
-		
+
 		/**
 		*Core to change the value of a field property, inline.
 		*
@@ -783,18 +784,18 @@ function replace_value($matches,$value) {
 		**/
 		function _set_field_value($line,$value) {
 		//----------------------------------------
-		
+
 			$verbose_set=($this->verbose&&($this->verbose_level>1));
 			//get the line content
 			$CurLine =$this->pdf_entries[$line];
-		
+
 			$OldLen=strlen($CurLine);
-			
+
 			//My PHP4/5 static call hack, only to make the callback $this->replace_value($matches,"$value") possible!
 			$callback_code='$THIS=new FPDM("[_STATIC_]");return $THIS->replace_value($matches,"'.$value.'");';
-			
+
 			$field_regexp='/^\/(\w+)\s?(\<|\()([^\)\>]*)(\)|\>)/';
-			
+
 			if(preg_match($field_regexp,$CurLine)) {
 				//modify it according to the new value $value
 				$CurLine = preg_replace_callback(
@@ -805,15 +806,15 @@ function _set_field_value($line,$value) {
 			}else {
 				if($verbose_set) echo("<br>WARNING:".htmlentities("Can not access to the value: $CurLine using regexp $field_regexp"));
 			}
-			
-			
+
+
 			$NewLen=strlen($CurLine);
 			$Shift=$NewLen-$OldLen;
 			$this->shift=$this->shift+$Shift;
-			
+
 			//Saves
 			$this->pdf_entries[$line]=$CurLine;
-			
+
 			return $Shift;
 		}
 
@@ -822,7 +823,7 @@ function _encode_value($str) {
 				$str="\xFE\xFF".iconv('UTF-8','UTF-16BE',$str);
 			return $this->_bin2hex($str);
 		}
-		
+
 		function _set_field_value2($line,$value,$append) {
 			$CurLine=$this->pdf_entries[$line];
 			$OldLen=strlen($CurLine);
@@ -855,57 +856,82 @@ function _set_field_value2($line,$value,$append) {
 		/**
 		*Changes the value of a field property, inline.
 		*
-		*@param string $type supported values for type are 'default' , 'current' or 'tooltip' 
+		*@param string $type supported values for type are 'default' , 'current' or 'tooltip'
 		*@param string $name name of the field annotation to change the value
 		*@param string $value the new value to set
 		**/
 		function set_field_value($type,$name,$value) {
 		//------------------------------------
 			$verbose_set=($this->verbose&&($this->verbose_level>1));
-			
+
 			//Get the line(s) of the misc field values
 			if(isset($this->value_entries["$name"])) {
-				
+
 				$object_id=$this->value_entries["$name"]["infos"]["object"];
-				
+
 				if($type=="tooltip") {
-			 
+
 					$offset_shift=$this->set_field_tooltip($name,$value);
-			 
+
 				} elseif ($this->useCheckboxParser && isset($this->value_entries["$name"]['infos']['checkbox_state'])) { //FIX: set checkbox value
+                    if (isset($this->value_entries["$name"]['infos']['parent_obj'])
+                        && isset($this->value_entries["$name"]["infos"]["checkbox_no"])
+                        && isset($this->value_entries["$name"]["infos"]["checkbox_yes"])) {
+                        $parent_obj = $this->value_entries["$name"]['infos']['parent_obj'];
+                        // We search for the position of the parent object:
+                        // The object ID has a space at the line end!
+                        $parent_obj_line = array_search($parent_obj . ' 0 obj ', $this->pdf_entries);
+                        if ($parent_obj_line === false) {
+                            if ($this->verbose&&($this->verbose_level>1)) {
+                                echo "<br>Could not find object [$parent_obj] which is the parent of checkbox [$name]";
+                            }
+                        } else {
+                            // insert a new line (with the selected value) in the parent object
+                            $state = $this->value_entries["$name"]["infos"]["checkbox_no"];
+                            if ($value) {
+                                $state = $this->value_entries["$name"]["infos"]["checkbox_yes"];
+                            }
+
+                            $state_line = " /V /$state ";
+                            $this->pdf_entries[$parent_obj_line + 4] = $this->pdf_entries[$parent_obj_line + 4] . $state_line;
+
+                            $offset_shift = strlen($state_line);
+                            $this->apply_offset_shift_from_object($parent_obj,$offset_shift);
+                        }
+                    }
                     $offset_shift=$this->set_field_checkbox($name, $value);
-                //ENDFIX
+                    //ENDFIX
                 } else {//if(isset($this->value_entries["$name"]["values"]["$type"])) {
 //				echo $this->value_entries["$name"]["values"]["$type"];
 /*					$field_value_line=$this->value_entries["$name"]["values"]["$type"];
 					$field_value_maxlen=$this->value_entries["$name"]["constraints"]["maxlen"];
-					
+
 					if($field_value_maxlen) //Truncates the size if needed
-						$value=substr($value, 0, $field_value_maxlen);				
-						
+						$value=substr($value, 0, $field_value_maxlen);
+
 					if($verbose_set) echo "<br>Change $type value of the field $name at line $field_value_line to '<i>$value</i>'";
 					$offset_shift=$this->_set_field_value($field_value_line,$value);*/
 					if(isset($this->value_entries[$name]["values"]["current"]))
 						$offset_shift=$this->_set_field_value2($this->value_entries[$name]["values"]["current"],$value,false);
 					else
 						$offset_shift=$this->_set_field_value2($this->value_entries[$name]["infos"]["name_line"],$value,true);
-				}						
+				}
 //				}else
 //					$this->Error("set_field_value failed as invalid valuetype $type for object $object_id");
-					
-					
+
+
 				//offset size shift will affect the next objects offsets taking into accound the order they appear in the file--
 				$this->apply_offset_shift_from_object($object_id,$offset_shift);
-					
-			} else 
+
+			} else
 				$this->Error("field $name not found");
-			
+
 		}
-		
-		
+
+
 		/**
 		*Changes the tooltip value of a field property, inline.
-		* 
+		*
 		*@param string $name name of the field annotation to change the value
 		*@param string $value the new value to set
 		*@return int offset_shift the size variation
@@ -914,7 +940,7 @@ function set_field_tooltip($name,$value) {
 		//------------------------------------
 			$offset_shift=0;
 			$verbose_set=($this->verbose&&($this->verbose_level>1));
-			
+
 			//Get the line(s) of the misc field values
 			if(isset($this->value_entries["$name"])) {
 				$field_tooltip_line=$this->value_entries["$name"]["infos"]["tooltip"];
@@ -924,11 +950,11 @@ function set_field_tooltip($name,$value) {
 				}else {
 					if($verbose_set) echo "<br>Change toolpip value aborted, the field $name has no tooltip definition.";
 				}
-			} else 
+			} else
 				$this->Error("set_field_tooltip failed as the field $name does not exist");
 			return $offset_shift;
 		}
-		
+
         //FIX: parse checkbox definition
         /**
         *Changes the checkbox state.
@@ -982,9 +1008,9 @@ public function set_field_checkbox($name, $value)
             return $offset_shift;
         }
         //ENDFIX
-		
+
 		/**
-		*Dumps the line entries 
+		*Dumps the line entries
 		*
 		*@note for debug purposes
 		*@access private
@@ -1002,8 +1028,8 @@ function dumpEntries($entries,$tag="",$halt=false) {
 			}
 			if($halt) exit();
         }
-		
-		
+
+
 		/**
 		*Dumps the string content
 		*
@@ -1023,7 +1049,7 @@ function dumpContent($content,$tag="",$halt=false) {
 			}
 			if($halt) exit();
         }
-		
+
 		/**
 		*Retrieves the content of a file as a string
 		*
@@ -1038,7 +1064,7 @@ function getContent($filename,$filetype) {
 			$handle=fopen($filename,'rb');
 			$content = fread($handle, filesize($filename));
 			fclose($handle);
-			
+
             if (!$content)
                 $this->Error(sprintf('Cannot open '.$filetype.' file %s !', $filename));
 
@@ -1054,13 +1080,13 @@ function getContent($filename,$filetype) {
 					$this->Error('Incremental updates are not supported');
 				$this->needAppearancesTrue = (strpos($content, '/NeedAppearances true')!==false);
 			}
-				
+
           /*  if($this->verbose) {
 				$this->dumpContent($content,"$filetype file content read");
             }*/
             return $content;
         }
-		
+
 		/**
 		*Retrieves the content of a file as an array of lines entries
 		*
@@ -1073,14 +1099,14 @@ function getEntries($filename,$filetype) {
         //----------------------------------------
 			$content=$this->getContent($filename,$filetype);
 			$entries=explode("\n",$content);
-				
+
            /* if($this->verbose) {
 				$this->dumpEntries($entries,"$filetype file entries");
             }*/
             return $entries;
         }
 
-		
+
 		/**
 		*Retrieves a binary string from its hexadecimal representation
 		*
@@ -1094,22 +1120,22 @@ function _hex2bin ($hexString)
 		{
 			//echo "<br>_hex2bin($hexString)";
 			$BinStr = '';
-		
+
 			$hexLength=strlen($hexString);
 			// only hex numbers is allowed
 			 if ($hexLength % 2 != 0 || preg_match("/[^\da-fA-F]/",$hexString)) return FALSE;
-		
-		
+
+
 			//Loop through the input and convert it
 			for ($i = 0; $i < $hexLength; $i += 2)
 				$BinStr .= '%'.substr ($hexString, $i, 2);
-		
-			
+
+
 			// Raw url-decode and return the result
 			return rawurldecode ($BinStr);//chr(hexdec())
 		}
-	
-	
+
+
 		/**
 		*Encodes a binary string to its hexadecimal representation
 		*
@@ -1127,9 +1153,9 @@ function _bin2hex($str) {
 				$i++;
 			} while ($i < strlen($str));
 			return $hex;
-		}	
-		
-		
+		}
+
+
 		/**
          * Extracts the map object for the xref table
 		 * @note PDF lines should have been previouly been parsed to make this work
@@ -1139,18 +1165,18 @@ function get_xref_table() {
 		//------------------------
 			return $this->value_entries['$_XREF_$'];
 		}
-		
+
 		/**
-         * Extracts the offset of the xref table 
+         * Extracts the offset of the xref table
 		 * @note PDF lines should have been previouly been parsed to make this work
 		 * @return int the xrefstart value
          */
 		function get_xref_start() {
 		//------------------------
-			return $this->value_entries['$_XREF_$']["infos"]["start"]["pointer"]; 
+			return $this->value_entries['$_XREF_$']["infos"]["start"]["pointer"];
 		}
-		
-		
+
+
 		/**
          * Extracts the line where the offset of the xref table is stored
 		 * @note PDF lines should have been previouly been parsed to make this work
@@ -1160,7 +1186,7 @@ function get_xref_start_line() {
 		//-------------------------------
 			return $this->value_entries['$_XREF_$']["infos"]["start"]["line"];
 		}
-		
+
 		/**
          * Calculates the offset of the xref table
 		 *
@@ -1172,8 +1198,8 @@ function get_xref_start_value() {
 			$xref_start=$this->get_xref_start();
 			return $xref_start+$size_shift;
 		}
-		
-		
+
+
 		/**
          * Read the offset of the xref table directly from file content
 		 *
@@ -1187,8 +1213,8 @@ function read_xref_start_value() {
 			$chunks = preg_split('/\bxref\b/', $buffer, -1, PREG_SPLIT_OFFSET_CAPTURE);
 			return intval($chunks[1][1])-4; //-4 , relative to end of xref
 		}
-		
-		
+
+
 		/**
          * Calculates the new offset/xref for this object id by applying the offset_shift due to value changes
 		 *
@@ -1198,14 +1224,14 @@ function read_xref_start_value() {
          */
 		function get_offset_object_value($object_id) {
 		//--------------------------------------------
-		
+
 			//Static is to keep forever...
 			static $offsets=null;
 			static $positions=null;
 			static $shifts=null;
-			
+
 			//if(is_null($offsets)) { //...variables content set once. This is the beauty of php :)
-			
+
 				//!NOTE: xref table is ordered by object id (position's object is not defined linearly in the pdf !)
 				$positions=$this->_get_positions_ordered();
 				//Makes it 0 indexed as object id starts from 1 and positions starts from 0
@@ -1213,14 +1239,14 @@ function get_offset_object_value($object_id) {
 				//Shifts are already 0 indexed, don't change.
 				$shifts=$this->shifts;
 			//}
-			
+
 			$p=$positions[$object_id];
 			$offset=$offsets[$p];
 			$shift=$shifts[$p]; //size shift of the object due to value changes
 			return $offset+$shift;
 		}
-		
-		
+
+
 		/**
          * Reads the offset of the xref table directly from file content
 		 *
@@ -1237,60 +1263,60 @@ function read_offset_object_value($object_id) {
 			$offset=intval($chars[1][1])-strlen($object_header)+strlen($previous_object_footer)+2;
 			return $offset;
 		}
-		
-		
+
+
 		/**
          * Fix the offset of the xref table
-         * 
+         *
          */
 		function fix_xref_start() {
-		//-------------------------	
-				
+		//-------------------------
+
 			$pdf_entries=&$this->pdf_entries;
-			$verbose_fix=($this->verbose&&($this->verbose_level>1));			
+			$verbose_fix=($this->verbose&&($this->verbose_level>1));
 			$calculate_xrefstart_value=((!$this->safe_mode)||$this->check_mode);
 			$extract_xrefstart_value_from_file=($this->safe_mode||$this->check_mode);
-				
-			if($calculate_xrefstart_value) {		
+
+			if($calculate_xrefstart_value) {
 				$xref_start_value_calculated=$this->get_xref_start_value(); //get computed value from old one
 				if(!$this->safe_mode) $xref_start_value=$xref_start_value_calculated;
 			}
-			
-			if($extract_xrefstart_value_from_file) { 
+
+			if($extract_xrefstart_value_from_file) {
 				$xref_start_value_safe=$this->read_xref_start_value();//read direct from new file content
 				if($this->safe_mode) $xref_start_value=$xref_start_value_safe;
-			} 
+			}
 
 			if($this->check_mode) { //Compared calculated value with position value read direct from file
 				if($xref_start_value_calculated != $xref_start_value_safe) {
 					if($verbose_fix) echo "<br>xrefstart's value must be $xref_start_value_safe calculated is $xref_start_value_calculated.Don't worry, FPDFM-merge will fix it for you.<br>";
 					$xref_start_value=$xref_start_value_safe; //Overrides with the good value
-					if($this->halt_mode) 
+					if($this->halt_mode)
 					    $this->Error("Halt on error mode enabled, aborting. Use \$pdf->set_modes('halt',false); to disable this mode and go further fixing corrupted pdf.");
 				} else {
 					if($verbose_fix) echo "<br>xrefstart's value for the file is correct and vaults <b>$xref_start_value</b>";
 				}
 			}
-			
+
 			//updates xrefstart's value
 			$xref_start_line=$this->get_xref_start_line();
 			$pdf_entries[$xref_start_line]="$xref_start_value";
 		}
-		
+
 		/**
          * Get the offsets table 0 indexed
-         * 
-		 * @return array $offsets 
+         *
+		 * @return array $offsets
          */
 		function _get_offsets_starting_from_zero() {
 		//-------------------------------------------
-			$offsets=$this->offsets; 
-			return array_values($offsets); 
+			$offsets=$this->offsets;
+			return array_values($offsets);
 		}
-		
+
 		/**
          * Sorts the position array by key
-         * 
+         *
 		 * @return array $positions the ordered positions
          */
 		function _get_positions_ordered() {
@@ -1299,57 +1325,57 @@ function _get_positions_ordered() {
 			ksort($positions);
 			return $positions;
 		}
-		
+
 		/**
          * Fix the xref table by rebuilding its offsets entries
-         * 
+         *
          */
 		function fix_xref_table() {
 		//------------------------
-	
+
 			$xref_table=$this->get_xref_table();
 			$xLen=$xref_table["infos"]["count"];
 			$pdf_entries=&$this->pdf_entries;
-			
+
 			//Do some checks
-			$offsets=$this->offsets; 
-			//$offsets=array_values($offsets); 
+			$offsets=$this->offsets;
+			//$offsets=array_values($offsets);
 			$oLen=count($offsets);
-			
-			
-			if($xLen == $oLen) { //...to rectify xref entries 
-			
+
+
+			if($xLen == $oLen) { //...to rectify xref entries
+
 				//jump over len and header, this is the first entry with n
 				$first_xref_entry_line=$xref_table["infos"]["line"]+3;
-				
+
 				//echo "xREF:{$pdf_entries[$first_xref_entry_line]}";
-			
+
 				//!NOTE: xref table is ordered by object id (position's object is not defined linearly in the pdf !)
 				//$positions=$this->positions;
 				//ksort($positions);
 				$verbose_fix=($this->verbose&&($this->verbose>1));
 				$calculate_offset_value=((!$this->safe_mode)||$this->check_mode);
 				$extract_offset_value_from_file=($this->safe_mode||$this->check_mode);
-				
+
 				//Get new file content (ie with values changed)
 				//$this->get_buffer()=$this->get_buffer();
-				
+
 				for($i=0;$i<$xLen;$i++) {
-				
+
 					$obj_id=$i+1;
-					
+
 					//Try two way to retrieve xref offset value of an object of the given id
-					
+
 					if($calculate_offset_value) {
 						$offset_value_calculated=$this->get_offset_object_value($obj_id);;
 						if(!$this->safe_mode) $offset_value=$offset_value_calculated;
 					}
-					
+
 					if($extract_offset_value_from_file) {
-						$offset_value_read=$this->read_offset_object_value($obj_id);	
+						$offset_value_read=$this->read_offset_object_value($obj_id);
 						if($this->safe_mode) $offset_value=$offset_value_read;
-					} 
-					
+					}
+
 					if($this->check_mode) {
 						if($offset_value_calculated !=  $offset_value_read)  {
 							if($verbose_fix) echo "<br>Offset for object $obj_id read is <b>$offset_value_read</b>, calculated $offset_value_calculated";
@@ -1361,19 +1387,19 @@ function fix_xref_table() {
 					}
 					$pdf_entries[$first_xref_entry_line+$i]=sprintf('%010d 00000 n ',$offset_value);
 				}
-				
-			}else { 
+
+			}else {
 				//Congratulations you won the corrupted Error Prize
-				$this->Error("Number of objects ($oLen) differs with number of xrefs ($xLen), something , pdf xref table is corrupted :("); 
+				$this->Error("Number of objects ($oLen) differs with number of xrefs ($xLen), something , pdf xref table is corrupted :(");
 			}
-			
-				
+
+
 		}
-	
-	
+
+
 		/**
          * Applies a shift offset $shift from the object whose id is given as param
-         * 
+         *
          * @note offset shift will affect the next objects taking into accound the order they appear in the file
          * @access public
          * @param int object_id the id whose size shift has changed
@@ -1385,13 +1411,13 @@ function apply_offset_shift_from_object($object_id,$offset_shift) {
 			$object_pos=$this->positions[$object_id];
 			//get the next object position
 			$next_object_pos=$object_pos+1;
-			//Applies offset change to next following objects 				
+			//Applies offset change to next following objects
 			$this->_apply_offset_shift($next_object_pos,$offset_shift);
 		}
 
 		/**
          * Applies a shift offset $shift starting at the index $from to the shifts array
-         * 
+         *
          * @access private
          * @param int from  the index to start apply the shift
 		 * @param int shift the shift value to use
@@ -1400,19 +1426,19 @@ function _apply_offset_shift($from,$shift) {
 		//------------------------------------------
 			$offsets=&$this->shifts;
 			$params=array($from,$shift);
-			
+
 			foreach($offsets as $key=>$value) {
 				if($key>=$from) {
 					$offset=$offsets[$key]+$shift;
 					$offsets[$key]=$offset;
 				}
 			}
-			
+
 		}
-		
+
 		/**
          * Decodes a PDF value according to the encoding
-         * 
+         *
 		 * @access public
          * @param string $encoding  the encoding to use for decoding the value, only 'hex' is supported
 		 * @param string value a value to decode
@@ -1421,15 +1447,15 @@ function _apply_offset_shift($from,$shift) {
 		function decodeValue($encoding,$value) {
 		//----------------------------------------------
 			//echo "Decoding $encoding value($value)";
-			if($encoding=="hex") 
+			if($encoding=="hex")
 				$value=$this->pdf_decode_field_value($value);
 			return $value;
 		}
-		
+
 		/**
 		*Retrieve the list of supported filters
 		*
-		*@note Uses $FPDM_FILTERS array built dynamically 
+		*@note Uses $FPDM_FILTERS array built dynamically
 		*@param String $sep a separator to merge filter names, default is '|'
 		*@return String the suported filters
 		**/
@@ -1438,8 +1464,8 @@ function getFilters($sep="|") {
 			global $FPDM_FILTERS;
 			return implode($sep,$FPDM_FILTERS);
 		}
-		
-		
+
+
 		/**
 		*Get a filter by name
 		*
@@ -1460,15 +1486,15 @@ function getFilters($sep="|") {
 		**/
 		function getFilter($name) {
 		//---------------------
-			
+
 			switch($name) {
 				case "LZWDecode":
 					$filter=new FilterLZW();
 				break;
-				case "ASCIIHexDecode": 
+				case "ASCIIHexDecode":
 					$filter=new FilterASCIIHex();
 				break;
-				case "ASCII85Decode": 
+				case "ASCII85Decode":
 					$filter=new FilterASCII85();
 				break;
 				case "FlateDecode":
@@ -1480,62 +1506,62 @@ function getFilter($name) {
 				default:
 					$this->Error("getFilter cannot open stream of object because filter '{$name}' is not supported, sorry.");
 			}
-			
-			
-			return $filter;					
+
+
+			return $filter;
 		}
-	
-	
+
+
 		//========= Stream manipulation stuff (alpha, not used by now!) ================
-		
+
 		/**
          * Detect if the stream has a textual content
-         * 
+         *
 		 * @access public
          * @param string $stream the string content of the stream
-         * @return boolean 
+         * @return boolean
          */
 		function is_text_stream($stream_content) {
 		//--------------------------------------
 			return preg_match("/(\s*Td\s+[\<\(])([^\>\)]+)([\>\)]\s+Tj)/",$stream_content);
 		}
-	
+
 		/**
          * changes the text value of a text stream
-         * 
+         *
 		 * @access public
          * @param array $stream  the stream defintion retrieved during PDF parsing
-         * @param string $value the new text value 
+         * @param string $value the new text value
          */
 		function change_stream_value($stream,$value) {
 		//--------------------------------------------
-		
+
 			$entries=&$this->pdf_entries;
-		
+
 			$verbose_parsing=($this->verbose&&($this->verbose_level>3));
-			
+
 			if($is_text_stream) {
-			
+
 				$OldLen=$stream["length"]["value"];
 				$lMin=$stream["start"];
 				$lMax=$stream["end"];
-				
+
 				$stream_content=$this->_set_text_value($stream_content,$value);
 				$NewLen=strlen($stream_content);
-			
+
 				for($l=$lMin;$l<=$lMax;$l++) {
-				
+
 					if($l==$lMin) {
 						$entries[$lMin]=$stream_content;
-						
+
 						//Update the length
 						$stream_def_line=$stream["length"]["line"];
 						$stream_def=$entries[$stream_def_line];
-						
+
 						$stream_def=preg_replace("/\/Length\s*(\d+)/",'/Length '.$NewLen,$stream_def);
-						
+
 						$entries[$stream_def_line]=$stream_def;
-						
+
 						//update the filter type...
 						$stream_def_line=$stream["filters"]["line"];
 						$stream_def=$entries[$stream_def_line];
@@ -1544,34 +1570,34 @@ function change_stream_value($stream,$value) {
 							echo htmlentities(print_r($stream_def,true));
 							echo "</pre>";
 						}
-					
+
 						//...to filter Standard
 						$stream_def=preg_replace($this->streams_filter,'/Standard ',$stream_def);
-					
+
 						$entries[$stream_def_line]=$stream_def;
-						
+
 						//Update the shift
 						$size_shift=$NewLen-$OldLen;
 						$this->apply_offset_shift_from_object($obj,$size_shift);
-						
+
 					}else if($lmin!=$lMax) {
 						unset($entries[$l]);
 					}
 				}
-				
+
 				if($verbose_parsing) {
 					var_dump($stream_content);
 				}
 			}
 		}
-	
+
 		/**
          * Overrides value between  Td and TJ, ommiting <>
-         * 
+         *
          * @note core method
 		 * @access private
          * @param array $stream  the stream defintion retrieved during PDF parsing
-         * @param string $value the new text value 
+         * @param string $value the new text value
          */
         function _set_text_value($stream,$value) {
         //---------------------------------------
@@ -1580,10 +1606,10 @@ function _set_text_value($stream,$value) {
 			$stream=implode($chunks,'');
 			return $stream;
         }
-        
-	
+
+
         //================================
-		
+
 		function _extract_pdf_definition_value($name,$line,&$match) {
 		//-----------------------------------------------------------
 				global $FPDM_REGEXPS;
@@ -1601,7 +1627,7 @@ function extract_pdf_definition_value($name,$line,&$match) {
 					$value=$this->_extract_pdf_definition_value($name,$line,$match);
 				}else
 					$this->Error("extract_pdf_definition_value() does not support definition '$name'");
-					
+
 				/*if($name=="/Type") {
 					if(preg_match("/\//",$line,$foo)) {
 					var_dump($match);
@@ -1611,21 +1637,21 @@ function extract_pdf_definition_value($name,$line,&$match) {
 				return $value;
 		}
 
-	
+
 		/**
-         * Parses the lines entries of a PDF 
-         * 
+         * Parses the lines entries of a PDF
+         *
 		 * @access public
          * @param array $lines  the FDF content as an array of lines
 		 * @return integer the number of lines the PDF has
          */
 		function parsePDFEntries(&$lines){
 		//--------------------------------
-           
+
            $entries=&$this->pdf_entries;
-           
+
            $CountLines = count($entries);
-           
+
             $Counter=0;
             $obj=0; //this is an invalid object id, we use it to know if we are into an object
             //FIX: parse checkbox definition
@@ -1635,6 +1661,8 @@ function parsePDFEntries(&$lines){
             $ap_d_line=0;
             $as='';
             //ENDFIX
+            $parent_obj=0;
+            $fields_line=-1;
             $type='';
 			$subtype='';
 			$name='';
@@ -1647,23 +1675,23 @@ function parsePDFEntries(&$lines){
 			$stream=array();
 			$id_def=false; //true when parsing/decoding trailer ID
 			$id_single_line_def=false; //true when the two ID chunks are one the same line
-			$id_multi_line_def=false; //true or OpenOffice 3.2 
+			$id_multi_line_def=false; //true or OpenOffice 3.2
 			$creator='';
 			$producer='';
 			$creationDate='';
-			
+
 			$verbose_parsing=($this->verbose&&($this->verbose_level>3));
 			$verbose_decoding=($this->verbose&&($this->verbose_level>4));
-			
-            if($this->verbose) $this->dumpContent("Starting to parse $CountLines entries","PDF parse"); 
-            
+
+            if($this->verbose) $this->dumpContent("Starting to parse $CountLines entries","PDF parse");
+
 			while ( $Counter < $CountLines ){
-               
+
                 $CurLine = $entries[$Counter];
-                
+
                 if($verbose_parsing) $this->dumpContent($CurLine,"====Parsing Line($Counter)");
 				if(!$xref_table) {
-				
+
 					//Header of an object?
 					if(preg_match("/^(\d+) (\d+) obj/",$CurLine,$match)) {
 							$obj=intval($match[1]);
@@ -1678,37 +1706,37 @@ function parsePDFEntries(&$lines){
 							$object["constraints"]["maxlen"]=$default_maxLen;
 							$object["infos"]=array();
 							$object["infos"]["object"]=intval($obj);
-							$object["infos"]["tooltip"]=$default_tooltip_line; 
-							
-					} else { 
-					
+							$object["infos"]["tooltip"]=$default_tooltip_line;
+
+					} else {
+
 						//Object has been opened
 						if($obj) {
-						
+
 							//Footer of an object?
 							if(preg_match("/endobj/",$CurLine,$match)) {
 								if($verbose_parsing) $this->dumpContent("","====Closing object($obj) at line $Counter");
-								
+
 								//We process fields here, save only Annotations texts that are supported by now
 								if($subtype=="Widget") {
-								
+
 									if($name != '') {
 										$lines["$name"]=$object;
 										if($verbose_parsing) $this->dumpContent("$type $subtype (obj id=$obj) is a text annotation of name '$name', saves it.");
 									}//else
 //										$this->Error("$type $subtype (obj id=$obj) is a text annotation without a name, this cannot be.");
-									
-									
+
+
 									$values=$object["values"];
-									
+
 									//Sanity values checks, watchdog.
 //									if(!array_key_exists("current",$values)) $this->Error("Cannot find value (/V) for field $name");
 //									if(!array_key_exists("default",$values)) $this->Error("Cannot find default value (/DV) for field $name");
-									
+
 								}else
 									if($verbose_parsing) $this->dumpContent("Object $type $subtype (obj id=$obj) is not supported");
-								
-								
+
+
 								$object=null;
 								$obj=0;
 								//FIX: parse checkbox definition
@@ -1718,14 +1746,15 @@ function parsePDFEntries(&$lines){
 								$ap_d_line=0;
 								$as='';
 								//ENDFIX
+                                $parent_obj=0;
 								$type='';
 								$subtype='';
 								$name='';
 								$value='';
 								$maxLen=0;
-								
+
 							} else {
-							
+
 								if(preg_match("/\/Length\s*(\d+)/",$CurLine,$match)) {
 									$stream["length"]=array("line"=>$Counter,"value"=>$match[1]);
 									$stream["start"]=0;
@@ -1733,92 +1762,92 @@ function parsePDFEntries(&$lines){
 									$stream["content"]='';
 									if($verbose_parsing) $this->dumpContent($CurLine,"->Stream filter length definition(<font color=\"darkorange\">{$match[1]}</font>) for object($obj) at line $Counter");
 								}
-								
+
 								//Handles single filter /Filter /filter_type as well as well as filter chains such as /Filter [/filter_type1 /filter_type2 .../filter_typeN]
 								if(preg_match_all($this->streams_filter,$CurLine,$matches)) {
-									
+
 									//$this->dumpContent($this->streams_filter);
 									/*$stream_filter=$match[1];
 									$stream_filter=trim(preg_replace('/(<<|\/Length\s*\d+|>>)/', '', $stream_filter),' ');
 									$stream_filters=preg_split('/\s*\//',$stream_filter);
 									array_shift($stream_filters);*/
 									$stream_filters=$matches[2];
-									$stream["filters"]=array("line"=>$Counter, "type"=>$stream_filters); 
+									$stream["filters"]=array("line"=>$Counter, "type"=>$stream_filters);
 									if($verbose_parsing) {
 										//var_dump($stream_filters);
 										$stream_filter=implode(" ",$stream_filters);
 										$this->dumpContent($CurLine,"->Stream filter type definition(<font color=\"darkorange\">$stream_filter</font>) for object($obj) at line $Counter");
 									}
-								}	
-								
+								}
+
 								if(array_key_exists("length",$stream)) { //length is mandatory
-									
+
 									if(preg_match("/\b(stream|endstream)\b/",$CurLine,$match)) {
-									
+
 										if(!array_key_exists("filters",$stream))  {//filter type is optional, if none is given, its standard
-											
+
 											$stream["filters"]=array("type"=>array("Standard"));
 											if($verbose_parsing) {
 												var_dump($stream);
 												$this->dumpContent($CurLine,"->No stream filter type definition for object($obj) was found, setting it to '<font color=\"darkorange\">Standard</font>'");
-											}	
+											}
 										}
-										
-									
+
+
 										if($match[1] == "stream") {
 											if($verbose_parsing) $this->dumpContent($CurLine,"->Opening stream for object($obj) at line $Counter");
 											$stream["start"]=$Counter+1;
 										}else {
 											$stream["end"]=$Counter-1;
-											
+
 											$stream["content"]=implode("\n",array_slice($entries,$stream["start"],$stream["end"]-$stream["start"]+1));
-											
-											
-											
+
+
+
 											$filters=$stream["filters"]["type"];
 											$f=count($filters);
 											$stream_content=$stream["content"];
-											
+
 											//var_dump($filters);
-											
+
 											//$filters_type=$filters["type"];
-											
+
 											//now process the stream, ie unpack it if needed
-											//by decoding in the reverse order the streams have been encoded 
-											//This is done by applying decode using the filters in the order given by /Filter. 
+											//by decoding in the reverse order the streams have been encoded
+											//This is done by applying decode using the filters in the order given by /Filter.
 											foreach($filters as $filter_name) {
-												
+
 												$stream_filter=$this->getFilter($filter_name);
 												$stream_content=$stream_filter->decode($stream_content);
-												if($verbose_decoding) { 
+												if($verbose_decoding) {
 													echo "<br><font color=\"blue\"><u>Stream decoded using filter '<font color=\"darkorange\">$filter_name</font>'</u>:[<pre>";
 													var_dump($stream_content); //todo : manipulate this content and adjust offsets.
 													echo "</pre>]</font>";
 												}
 											}
-						
+
 											if($verbose_parsing) {
 												$this->dumpEntries($stream);
-												
+
 												echo "<font color=\"blue\">";
 												if($this->is_text_stream($stream_content)) {
 													echo "<u>Stream text unfiltered</u>:[<pre>";
 												} else {
 													echo "<u>Stream unfiltered</u>:[<pre>";
 												}
-												var_dump($stream_content); 
+												var_dump($stream_content);
 												echo "</pre>]</font>";
 												$this->dumpContent($CurLine,"->Closing stream for object($obj) at line $Counter");
 											}
-											
+
 											$stream=array();
 										}
-									}else if($stream["start"]>0){ 
+									}else if($stream["start"]>0){
 										//stream content line that will be processed on endstream...
 									}
-									
+
 								} else {
-								
+
 									/*
 									Producer<FEFF004F00700065006E004F00660066006900630065002E006F0072006700200033002E0032>
 									/CreationDate (D:20101225151810+01'00')>>
@@ -1828,19 +1857,19 @@ function parsePDFEntries(&$lines){
 										if($verbose_parsing) echo("Creator read ($creator)");
 										$this->info["Creator"]=$creator;
 									}
-								
+
 									if(($producer=='')&&preg_match("/\/Producer\<([^\>]+)\>/",$CurLine,$values)) {
 										$producer=$this->decodeValue("hex",$values[1]);
 										if($verbose_parsing) echo("Producer read ($producer)");
 										$this->info["Producer"]=$producer;
 									}
-									
+
 									if(($creationDate=='')&&preg_match("/\/CreationDate\(([^\)]+)\)/",$CurLine,$values)) {
 										$creationDate=$values[1];
 										if($verbose_parsing) echo("Creation date read ($creationDate)");
 										$this->info["CreationDate"]=$creationDate;
 									}
-								
+
 									//=== DEFINITION ====
 									//preg_match("/^\/Type\s+\/(\w+)$/",$CurLine,$match)
 									$match=array();
@@ -1856,6 +1885,12 @@ function parsePDFEntries(&$lines){
                                                 echo("<br>Found D Line '<i>$Counter</i>'");
                                             }
                                             $ap_d_line = $Counter;
+                                        } elseif (!$parent_obj&&$this->extract_pdf_definition_value("/Parent", $CurLine, $match)) {
+                                            $parent_obj = intval($match[1]);
+                                            if ($verbose_parsing) {
+                                                echo("<br>Found Parent is '<i>$parent_obj</i>'");
+                                            }
+                                            $object["infos"]["parent_obj"] = $parent_obj;
                                         } elseif (($ap_line==$Counter-4)&&($ap_d_line==$Counter-2)&&($ap_d_yes=='')&&$this->extract_pdf_definition_value("name", $CurLine, $match)) {
                                             $ap_d_yes=$match[1];
                                             if ($verbose_parsing) {
@@ -1879,48 +1914,48 @@ function parsePDFEntries(&$lines){
 									}
 									//ENDFIX
 									if(($type=='')||($subtype=='')||($name=="")) {
-									
+
 										if(($type=='')&&$this->extract_pdf_definition_value("/Type",$CurLine,$match)) {
-										
+
 											if($match[1]!='Border') {
 												$type=$match[1];
 												if($verbose_parsing) echo("<br>Object's type is '<i>$type</i>'");
 											}
-											
+
 										}
 										if(($subtype=='')&&$this->extract_pdf_definition_value("/Subtype",$CurLine,$match)) {
-										
+
 											$subtype=$match[1];
 											if($verbose_parsing) echo("<br>Object's subType is '<i>$subtype</i>'");
-											
+
 										}
 										if(($name=="")&&preg_match("/^\/T\s?\((.+)\)\s*$/",$this->_protectContentValues($CurLine),$match)) {
-								
+
 											$name=$this->_unprotectContentValues($match[1]);
 											//FIX: convert ASCII object names to utf-8
 											// don't use utf8_encode($name) yet, it's core function since php 7.2
 											$name = mb_convert_encoding($name, 'UTF-8', 'ASCII');
 											//ENDFIX
 											if($verbose_parsing) echo ("Object's name is '<i>$name</i>'");
-											
+
 											$object["infos"]["name"]=$name; //Keep a track
 											$object["infos"]["name_line"]=$Counter;
-											
+
 											//$this->dumpContent(" Name [$name]");
 										}
-										
-									}// else { 
-									
+
+									}// else {
+
 										//=== CONTENT ====
-									
+
 										//$this->dumpContent($CurLine);
 										//=== Now, start the serious work , read DV, V Values and eventually TU
 										//note if(preg_match_all("/^\/(V|DV)\s+(\<|\))([^\)\>]+)(\)|\>)/",$CurLine,$matches)) {
 										//do not work as all is encoded on the same line...
-										if(preg_match("/^\/(V|DV|TU)\s+([\<\(])/",$CurLine,$def)) { 
-											
+										if(preg_match("/^\/(V|DV|TU)\s+([\<\(])/",$CurLine,$def)) {
+
 											//get an human readable format of value type and encoding
-											
+
 											if($def[1] == "TU") {
 												$valuetype="info";
 												$object["infos"]["tooltip"]=$Counter;
@@ -1928,49 +1963,50 @@ function parsePDFEntries(&$lines){
 												$valuetype=($def[1] == "DV") ? "default" : "current";
 												$object["values"]["$valuetype"]=$Counter; //Set a marker to process lately
 											}
-											
+
 											$encoding=($def[2]=="<") ? "hex" : "plain";
-											
+
 											if(preg_match("/^\/(V|DV|TU)\s+(\<|\)|\()([^\)\>]*)(\)|\>\))/",$CurLine,$values)) {
 												$value=$values[3];
 												$value=$this->decodeValue($encoding,$value);
-											}else 
+											}else
 												$value='';
-											
-											if($verbose_parsing) 
+
+											if($verbose_parsing)
 												$this->dumpContent("$type $subtype (obj id=$obj) has $encoding $valuetype value [$value] at line $Counter");
-											
-											
+
+
 										}else if(preg_match("/^\/MaxLen\s+(\d+)/",$CurLine,$values)) {
 											$maxLen=$values[1];
 											$object["constraints"]["maxlen"]=intval($maxLen);
 										} else
 											if($verbose_parsing) echo("WARNING: definition ignored");
-										
+
 										if(substr($CurLine,0,7)=='/Fields' && !$this->needAppearancesTrue) {
 											$CurLine='/NeedAppearances true '.$CurLine;
 											$entries[$Counter]=$CurLine;
+                                            $fields_line = $Counter;
 										}
-										
+
 										//TODO: Fetch the XObject..and change Td <> Tj
 /*										if(preg_match("/^\/AP/",$CurLine,$values)) {
 											//die("stop");
 											$CurLine=''; //clear link to Xobject
 											$entries[$Counter]=$CurLine;
 										}*/
-										
-//									} 
-									
+
+//									}
+
 								}
-							
-							
+
+
 							}
-						
+
 						}
-						 
+
 						//~~~~~Xref table header? ~~~~~~
 						if(preg_match("/\bxref\b/",$CurLine,$match)) {
-						
+
 							$xref_table=1;
 							if($verbose_parsing) $this->dumpContent("->Starting xref table at line $Counter:[$CurLine]");
 							$lines['$_XREF_$']=array();
@@ -1981,73 +2017,73 @@ function parsePDFEntries(&$lines){
 							$start_pointer=$this->pointer+strpos($CurLine,"xref"); //HACK for PDFcreator 1.0.0
 							$lines['$_XREF_$']["infos"]["start"]["pointer"]=$start_pointer;
 						}
-			
+
 					}
 					$obj_header=false;
-			} else { 
+			} else {
 					//We are inside the xref table
 					//$this->dumpContent($CurLine,"");
 					$xref_table=$xref_table+1;
 					switch($xref_table) {
-						case 2: 
+						case 2:
 							if(preg_match("/^(\d+) (\d+)/",$CurLine,$match)) {
 								$refs_count=intval($match[2]);//xref_table length+1 (includes this line)
-								$lines['$_XREF_$']["infos"]["count"]=$refs_count-1; 
+								$lines['$_XREF_$']["infos"]["count"]=$refs_count-1;
 								if($verbose_parsing) $this->dumpContent("Xref table length is $refs_count");
 							}else
 								if($verbose_parsing) $this->dumpContent("WARNING: Xref table length ignored!");
 						break;
 						case 3:
-							//Should be 0000000000 65535 f 
+							//Should be 0000000000 65535 f
 							if($verbose_parsing) $this->dumpContent("this is Xref table header, should be 0000000000 65535 f ");
 						break;
 						default:
 							//xref entries
 							if($refs_count>0) {
 								$xref=$xref_table-3;
-								 
+
 								if($refs_count == 1) {//Last one , due to the shift, is the trailer
 									if(!preg_match("/^trailer/",$CurLine)) //if not, Houston we have a problem
-										$this->Error("xref_table length corrupted?: Trailer not found at expected!");			
+										$this->Error("xref_table length corrupted?: Trailer not found at expected!");
 									else
 										$trailer_table=1;
 								}else {
 									$lines['$_XREF_$']["entries"][$xref]=$CurLine;
 									if($verbose_parsing) $this->dumpContent("Xref table entry for object $xref found.");
 								}
-								$refs_count--;	
+								$refs_count--;
 							} else { //We are inside the trailer
-							
+
 								if($trailer_table==1) { //should be <<
-									
+
 									if(trim($CurLine) != '') { //HACK: PDFCreator Version 1.0.0 has an extra CR after trailer
-										if(!preg_match("/<</",$CurLine,$match)) 
+										if(!preg_match("/<</",$CurLine,$match))
 											$this->Error("trailer_table corrupted?; missing start delimiter << ");
 										$trailer_table++;
 									}
-									
-				
+
+
 								}else if(($trailer_table>0)&&((!is_null($id_def))||preg_match("/^\/(Size|Root|Info|ID|DocChecksum)/",$CurLine,$match))) {
-								
+
 									//Value can be extracted using (\d+|\[[^\]]+\])
 									if(preg_match("/\/Size (\d+)/",$CurLine,$match)) {
 										//Seems to match with xref entries count..
 										$size_read=$match[1];
 										$this->info["size"]=$size_read;
 										if($verbose_parsing) $this->dumpContent("Size read ($size_read) for pdf found.");
-									}  
+									}
 
 									if(preg_match("/^\/ID\s*\[\s*<([\da-fA-F]+)/",$CurLine,$match)) {
 										$oid=$match[1];
 										$id_def=true;
 										if($verbose_parsing) $this->dumpContent("ID chunk one ($oid) for pdf found.");
-										
+
 										//Determines if the ID definition is one line...
 										if(preg_match("/\>\s?\</",$CurLine,$match))
 											$id_single_line_def=true;
-							
-									}  
-									
+
+									}
+
 									if($id_def) {//we are inside the ID definition
 										if($id_single_line_def||$id_multi_line_def) {
 											//decode the second ID chunk
@@ -2061,22 +2097,22 @@ function parsePDFEntries(&$lines){
 										} else
 											$id_multi_line_def=true;
 									}
-									
+
 									if(preg_match("/^\/DocChecksum \/([\da-fA-F]+)/",$CurLine,$match)) {
 										$checksum=$match[1];
 										$this->info["checksum"]=$checksum;
 										if($verbose_parsing) $this->dumpContent("Checksum read ($checksum) for pdf found.");
-									}  
-									
-									if(preg_match("/>>/",$CurLine,$match)) 
+									}
+
+									if(preg_match("/>>/",$CurLine,$match))
 										$trailer_table=-1;//negative value: expects startxref to follow
-									
-									
+
+
 								} else {
-	
+
 									switch($trailer_table) {
 										case -1://startxref
-										if(!preg_match("/^startxref/",$CurLine,$match)) 
+										if(!preg_match("/^startxref/",$CurLine,$match))
 											$this->Error("startxref tag expected, read $CurLine");
 										break;
 										case -2://startxref's value
@@ -2089,34 +2125,46 @@ function parsePDFEntries(&$lines){
 										default://%%EOF
 									}
 									$trailer_table--;
-											
+
 								}
-								
+
 							}
 					}
-					
+
 				}
-				
+
                 $this->pointer=$this->pointer+strlen($CurLine)+1; //+1 due to \n
                 $Counter++;
             }
-       
+
 			if($this->verbose) {
-			
-				$refs=(array_key_exists('$_XREF_$',$lines)) ? $lines['$_XREF_$']["infos"]["count"] : 0; 
+
+				$refs=(array_key_exists('$_XREF_$',$lines)) ? $lines['$_XREF_$']["infos"]["count"] : 0;
 				if($refs) {
 					$this->dumpContent("PDF parse retrieved $refs refs");
 				}else {
 					$this->dumpContent("PDF parse retrieved no refs, seems the xref table is broken or inacessible, this is bad!");
 				}
 			}
-			
+
+            // Remove checkbox parents from fields line, to make sure they will still be displayed, even if /NeedAppearance is set to true.
+            if ($fields_line !== -1) {
+                $fields = $this->pdf_entries[$fields_line];
+                foreach ($lines as $line) {
+                    if (isset($line['infos']['parent_obj'])) {
+                        $parent_obj = $line['infos']['parent_obj'];
+                        $fields = preg_replace('/(.*\/Fields\s\[(\d+\s\d\sR\s?)*)(' . $parent_obj . '\s\d\sR\s?)((\d+\s\d\sR\s?)*\])/', '$1$4', $fields);
+                    }
+                }
+                $this->pdf_entries[$fields_line] = $fields;
+            }
+
 			return count($lines);
         }
-		
+
 		 /**
          * Protect ( ) that may be in value or names
-         * 
+         *
 		 * @access protected
          * @param string $content  the FDF content to protect values
 		 * @return string the content protected
@@ -2127,7 +2175,7 @@ function _protectContentValues($content) {
 		   $content=str_replace("\\)","#@$",$content);
 		   return $content;
 		}
-		
+
 		 /**
          * Unprotect ( ) that may be in value or names
          *
@@ -2136,30 +2184,30 @@ function _protectContentValues($content) {
 		 * @return string the content unprotected
          */
 		function _unprotectContentValues($content) {
-		//--------------------------------------------------	
+		//--------------------------------------------------
 		   $content=str_replace("$@#","\\(",$content);
 		   $content=str_replace("#@$","\\)",$content);
 		   $content=stripcslashes($content);
 		   return $content;
 		}
-		
+
 		 /**
-         * Parses the content of a FDF file and saved extracted field data 
+         * Parses the content of a FDF file and saved extracted field data
          *
 		 *@access public
 		 *@return array $fields the data of the fields parsed
          */
 		function parseFDFContent(){
 		//-------------------------
-	   
+
 		   $content=$this->fdf_content;
 		   $content=$this->_protectContentValues($content);//protect ( ) that may be in value or names...
-		  
+
 		   if($this->verbose) $this->dumpEntries($content,"FDF parse");
-		   
-		   //..so that this regexp can do its job without annoyances 
+
+		   //..so that this regexp can do its job without annoyances
 			if(preg_match_all("/(T|V)\s*\(([^\)]+)\)\s*\/(T|V)\s*\(([^\)]+)\)/", $content,$matches, PREG_PATTERN_ORDER)) {
-	   
+
 				$fMax=count($matches[0]);
 				$fields=array();
 				for($f=0;$f<$fMax;$f++) {
@@ -2167,54 +2215,54 @@ function parseFDFContent(){
 					$name='';
 					if($matches[1][$f]=="V") {
 						$value=$matches[2][$f];
-						if($matches[3][$f]=="T") 
+						if($matches[3][$f]=="T")
 							$name=$matches[4][$f];
-						else 
+						else
 							$this->Error("Field $f ignored , incomplete field declaration, name is expected");
 					} else {
 						if($matches[1][$f]=="T") {
 							$name=$matches[2][$f];
-							if($matches[3][$f]=="V") 
+							if($matches[3][$f]=="V")
 								$value=$matches[4][$f];
-							else 
+							else
 								$this->Error("Field $f ignored , incomplete field declaration, value is expected");
-						} else 
+						} else
 							$this->Error("Field $f ignored , Invalid field keys ({$matches[0][$f]})");
 					}
 					if($name!='') {
-						if(array_key_exists($name,$fields)) 
+						if(array_key_exists($name,$fields))
 							 $this->Error("Field $f ignored , already defined");
 						else {
 							$name=$this->_unprotectContentValues($name);
 							$value=$this->_unprotectContentValues($value);
-							if($this->verbose) 
+							if($this->verbose)
 								$this->dumpContent("FDF field [$name] has its value set to \"$value\"");
 							$fields[$name]=$value;
 						}
-					} else 
+					} else
 						$this->Error("Field $f ignored , no name");
-					
+
 				}
 			} else
 				if($this->verbose) $this->dumpContent($fields,"FDF has no fields",false);
-			
+
 			if($this->verbose) $this->dumpContent($fields,"FDF parsed",false);
-			
+
 			return $fields;
 		}
-		
-		
+
+
         /**
          * Close the opened file
          */
         function closeFile() {
         //--------------------
         	if (isset($this->f) && is_resource($this->f)) {
-        	    fclose($this->f);	
+        	    fclose($this->f);
         		unset($this->f);
-        	}	
+        	}
         }
-        
+
         /**
          * Print Error and die
          *
@@ -2222,12 +2270,12 @@ function closeFile() {
          */
         function Error($msg) {
         //--------------------
-        	die('<b>FPDF-Merge Error:</b> '.$msg);	
+        	die('<b>FPDF-Merge Error:</b> '.$msg);
         }
-		
-		
+
+
 	}
-	
+
 }
 
 unset($__tmp);