<?php
/**
 * A PHP class to provide the basic functionality to create a pdf document without
 * any requirement for additional modules.
 *
 * Extended by Orion Richardson to support Unicode / UTF-8 characters using
 * TCPDF and others as a guide.
 *
 * @author  Wayne Munro <pdf@ros.co.nz>
 * @author  Orion Richardson <orionr@yahoo.com>
 * @author  Helmut Tischer <htischer@weihenstephan.org>
 * @author  Ryan H. Masten <ryan.masten@gmail.com>
 * @author  Brian Sweeney <eclecticgeek@gmail.com>
 * @author  Fabien Ménager <fabien.menager@gmail.com>
 * @license Public Domain http://creativecommons.org/licenses/publicdomain/
 * @package Cpdf
 */
class Cpdf {

  /**
   * @var integer The current number of pdf objects in the document
   */
  public $numObj = 0;

  /**
   * @var array This array contains all of the pdf objects, ready for final assembly
   */
  public $objects = array();

  /**
   * @var integer The objectId (number within the objects array) of the document catalog
   */
  public $catalogId;

  /**
   * @var array Array carrying information about the fonts that the system currently knows about
   * Used to ensure that a font is not loaded twice, among other things
   */
  public $fonts = array();

  /**
   * @var string The default font metrics file to use if no other font has been loaded.
   * The path to the directory containing the font metrics should be included
   */
  public $defaultFont = './fonts/Helvetica.afm';

  /**
   * @string A record of the current font
   */
  public $currentFont = '';

  /**
   * @var string The current base font
   */
  public $currentBaseFont = '';

  /**
   * @var integer The number of the current font within the font array
   */
  public $currentFontNum = 0;

  /**
   * @var integer
   */
  public $currentNode;

  /**
   * @var integer Object number of the current page
   */
  public $currentPage;

  /**
   * @var integer Object number of the currently active contents block
   */
  public $currentContents;

  /**
   * @var integer Number of fonts within the system
   */
  public $numFonts = 0;

  /**
   * @var integer Number of graphic state resources used
   */
  private $numStates = 0;

  /**
   * @var array Current color for fill operations, defaults to inactive value, 
   * all three components should be between 0 and 1 inclusive when active
   */
  public $currentColor = null;

  /**
   * @var array Current color for stroke operations (lines etc.)
   */
  public $currentStrokeColor = null;

  /**
   * @var string Current style that lines are drawn in
   */
  public $currentLineStyle = '';

  /**
   * @var array Current line transparency (partial graphics state)
   */
  public $currentLineTransparency = array("mode" => "Normal", "opacity" => 1.0);

  /**
   * array Current fill transparency (partial graphics state)
   */
  public $currentFillTransparency = array("mode" => "Normal", "opacity" => 1.0);

  /**
   * @var array An array which is used to save the state of the document, mainly the colors and styles
   * it is used to temporarily change to another state, the change back to what it was before
   */
  public $stateStack = array();

  /**
   * @var integer Number of elements within the state stack
   */
  public $nStateStack = 0;

  /**
   * @var integer Number of page objects within the document
   */
  public $numPages = 0;

  /**
   * @var array Object Id storage stack
   */
  public $stack = array();

  /**
   * @var integer Number of elements within the object Id storage stack
   */
  public $nStack = 0;

  /**
   * an array which contains information about the objects which are not firmly attached to pages
   * these have been added with the addObject function
   */
  public $looseObjects = array();

  /**
   * array contains infomation about how the loose objects are to be added to the document
   */
  public $addLooseObjects = array();

  /**
   * @var integer The objectId of the information object for the document
   * this contains authorship, title etc.
   */
  public $infoObject = 0;

  /**
   * @var integer Number of images being tracked within the document
   */
  public $numImages = 0;

  /**
   * @var array An array containing options about the document
   * it defaults to turning on the compression of the objects
   */
  public $options = array('compression' => true);

  /**
   * @var integer The objectId of the first page of the document
   */
  public $firstPageId;

  /**
   * @var float Used to track the last used value of the inter-word spacing, this is so that it is known
   * when the spacing is changed.
   */
  public $wordSpaceAdjust = 0;

  /**
   * @var float Used to track the last used value of the inter-letter spacing, this is so that it is known
   * when the spacing is changed.
   */
  public $charSpaceAdjust = 0;

  /**
   * @var integer The object Id of the procset object
   */
  public $procsetObjectId;

  /**
   * @var array Store the information about the relationship between font families
   * this used so that the code knows which font is the bold version of another font, etc.
   * the value of this array is initialised in the constuctor function.
   */
  public $fontFamilies = array();

  /**
   * @var string Folder for php serialized formats of font metrics files.
   * If empty string, use same folder as original metrics files.
   * This can be passed in from class creator.
   * If this folder does not exist or is not writable, Cpdf will be **much** slower.
   * Because of potential trouble with php safe mode, folder cannot be created at runtime.
   */
  public $fontcache = '';

  /**
   * @var integer The version of the font metrics cache file.
   * This value must be manually incremented whenever the internal font data structure is modified.
   */
  public $fontcacheVersion = 6;

  /**
   * @var string Temporary folder.
   * If empty string, will attempty system tmp folder.
   * This can be passed in from class creator.
   * Only used for conversion of gd images to jpeg images.
   */
  public $tmp = '';

  /**
   * @var string Track if the current font is bolded or italicised
   */
  public $currentTextState = '';

  /**
   * @var string Messages are stored here during processing, these can be selected afterwards to give some useful debug information
   */
  public $messages = '';

  /**
   * @var string The ancryption array for the document encryption is stored here
   */
  public $arc4 = '';

  /**
   * @var integer The object Id of the encryption information
   */
  public $arc4_objnum = 0;

  /**
   * @var string The file identifier, used to uniquely identify a pdf document
   */
  public $fileIdentifier = '';

  /**
   * @var boolean A flag to say if a document is to be encrypted or not
   */
  public $encrypted = false;

  /**
   * @var string The encryption key for the encryption of all the document content (structure is not encrypted)
   */
  public $encryptionKey = '';

  /**
   * @var array Array which forms a stack to keep track of nested callback functions
   */
  public $callback = array();

  /**
   * @var integer The number of callback functions in the callback array
   */
  public $nCallback = 0;

  /**
   * @var array Store label->id pairs for named destinations, these will be used to replace internal links
   * done this way so that destinations can be defined after the location that links to them
   */
  public $destinations = array();

  /**
   * @var array Store the stack for the transaction commands, each item in here is a record of the values of all the
   * publiciables within the class, so that the user can rollback at will (from each 'start' command)
   * note that this includes the objects array, so these can be large.
   */
  public $checkpoint = '';

  /**
   * @var array Table of Image origin filenames and image labels which were already added with o_image().
   * Allows to merge identical images
   */
  public $imagelist = array();

  /**
   * @var boolean Whether the text passed in should be treated as Unicode or just local character set.
   */
  public $isUnicode = false;

  /**
   * @var string the JavaScript code of the document
   */
  public $javascript = '';

  /**
   * @var boolean whether the compression is possible
   */
  protected $compressionReady = false;

  /**
   * @var array Current page size
   */
  protected $currentPageSize = array("width" => 0, "height" => 0);

  /**
   * @var array All the chars that will be required in the font subsets
   */
  protected $stringSubsets = array();

  /**
   * @var string The target internal encoding
   */
  static protected $targetEncoding = 'iso-8859-1';

  /**
   * @var array The list of the core fonts
   */
  static protected $coreFonts = array(
    'courier', 'courier-bold', 'courier-oblique', 'courier-boldoblique',
    'helvetica', 'helvetica-bold', 'helvetica-oblique', 'helvetica-boldoblique',
    'times-roman', 'times-bold', 'times-italic', 'times-bolditalic',
    'symbol', 'zapfdingbats'
  );

  /**
   * Class constructor
   * This will start a new document
   *
   * @param array   $pageSize  Array of 4 numbers, defining the bottom left and upper right corner of the page. first two are normally zero.
   * @param boolean $isUnicode Whether text will be treated as Unicode or not.
   * @param string  $fontcache The font cache folder
   * @param string  $tmp       The temporary folder
   */
  function __construct($pageSize = array(0, 0, 612, 792), $isUnicode = false, $fontcache = '', $tmp = '') {
    $this->isUnicode = $isUnicode;
    $this->fontcache = $fontcache;
    $this->tmp = $tmp;
    $this->newDocument($pageSize);

    $this->compressionReady = function_exists('gzcompress');
    
    if ( in_array('Windows-1252', mb_list_encodings()) ) {
      self::$targetEncoding = 'Windows-1252';
    }

    // also initialize the font families that are known about already
    $this->setFontFamily('init');
    //  $this->fileIdentifier = md5('xxxxxxxx'.time());
  }

  /**
   * Document object methods (internal use only)
   *
   * There is about one object method for each type of object in the pdf document
   * Each function has the same call list ($id,$action,$options).
   * $id = the object ID of the object, or what it is to be if it is being created
   * $action = a string specifying the action to be performed, though ALL must support:
   *           'new' - create the object with the id $id
   *           'out' - produce the output for the pdf object
   * $options = optional, a string or array containing the various parameters for the object
   *
   * These, in conjunction with the output function are the ONLY way for output to be produced
   * within the pdf 'file'.
   */

  /**
   * Destination object, used to specify the location for the user to jump to, presently on opening
   */
  protected function o_destination($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = &$this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'destination', 'info' => array());
      $tmp = '';
      switch ($options['type']) {
        case 'XYZ':
        case 'FitR':
          $tmp = ' '.$options['p3'].$tmp;
        case 'FitH':
        case 'FitV':
        case 'FitBH':
        case 'FitBV':
          $tmp = ' '.$options['p1'].' '.$options['p2'].$tmp;
        case 'Fit':
        case 'FitB':
          $tmp = $options['type'].$tmp;
          $this->objects[$id]['info']['string'] = $tmp;
          $this->objects[$id]['info']['page'] = $options['page'];
      }
      break;

    case 'out':
      $tmp = $o['info'];
      $res = "\n$id 0 obj\n".'['.$tmp['page'].' 0 R /'.$tmp['string']."]\nendobj";
      return $res;
    }
  }

  /**
   * set the viewer preferences
   */
  protected function o_viewerPreferences($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'viewerPreferences', 'info' => array());
      break;

    case 'add':
      foreach ($options as $k => $v) {
        switch ($k) {
          case 'HideToolbar':
          case 'HideMenubar':
          case 'HideWindowUI':
          case 'FitWindow':
          case 'CenterWindow':
          case 'NonFullScreenPageMode':
          case 'Direction':
            $o['info'][$k] = $v;
            break;
        }
      }
      break;

    case 'out':
      $res = "\n$id 0 obj\n<< ";
      foreach ($o['info'] as $k => $v) {
        $res.= "\n/$k $v";
      }
      $res.= "\n>>\n";
      return $res;
    }
  }

  /**
   * define the document catalog, the overall controller for the document
   */
  protected function o_catalog($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
      case 'new':
        $this->objects[$id] = array('t' => 'catalog', 'info' => array());
        $this->catalogId = $id;
        break;

      case 'outlines':
      case 'pages':
      case 'openHere':
      case 'javascript':
        $o['info'][$action] = $options;
        break;

      case 'viewerPreferences':
        if (!isset($o['info']['viewerPreferences'])) {
          $this->numObj++;
          $this->o_viewerPreferences($this->numObj, 'new');
          $o['info']['viewerPreferences'] = $this->numObj;
        }

        $vp = $o['info']['viewerPreferences'];
        $this->o_viewerPreferences($vp, 'add', $options);

        break;

      case 'out':
        $res = "\n$id 0 obj\n<< /Type /Catalog";

        foreach ($o['info'] as $k => $v) {
          switch ($k) {
            case 'outlines':
              $res.= "\n/Outlines $v 0 R";
              break;

            case 'pages':
              $res.= "\n/Pages $v 0 R";
              break;

            case 'viewerPreferences':
              $res.= "\n/ViewerPreferences $v 0 R";
              break;

            case 'openHere':
              $res.= "\n/OpenAction $v 0 R";
              break;

            case 'javascript':
              $res.= "\n/Names <</JavaScript $v 0 R>>";
              break;
          }
        }

        $res.= " >>\nendobj";
        return $res;
    }
  }

  /**
   * object which is a parent to the pages in the document
   */
  protected function o_pages($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'pages', 'info' => array());
      $this->o_catalog($this->catalogId, 'pages', $id);
      break;

    case 'page':
      if (!is_array($options)) {
        // then it will just be the id of the new page
        $o['info']['pages'][] = $options;
      }
      else {
        // then it should be an array having 'id','rid','pos', where rid=the page to which this one will be placed relative
        // and pos is either 'before' or 'after', saying where this page will fit.
        if (isset($options['id']) && isset($options['rid']) && isset($options['pos'])) {
          $i = array_search($options['rid'], $o['info']['pages']);
          if (isset($o['info']['pages'][$i]) && $o['info']['pages'][$i] == $options['rid']) {

            // then there is a match
            // make a space
            switch ($options['pos']) {
              case 'before':
                $k = $i;
                break;

              case 'after':
                $k = $i+1;
                break;

              default:
                $k = -1;
                break;
            }

            if ($k >= 0) {
              for ($j = count($o['info']['pages'])-1; $j >= $k; $j--) {
                $o['info']['pages'][$j+1] = $o['info']['pages'][$j];
              }

              $o['info']['pages'][$k] = $options['id'];
            }
          }
        }
      }
      break;

    case 'procset':
      $o['info']['procset'] = $options;
      break;

    case 'mediaBox':
      $o['info']['mediaBox'] = $options;
      // which should be an array of 4 numbers
      $this->currentPageSize = array('width' => $options[2], 'height' => $options[3]);
      break;

    case 'font':
      $o['info']['fonts'][] = array('objNum' => $options['objNum'], 'fontNum' => $options['fontNum']);
      break;

    case 'extGState':
      $o['info']['extGStates'][] = array('objNum' => $options['objNum'],  'stateNum' => $options['stateNum']);
      break;

    case 'xObject':
      $o['info']['xObjects'][] = array('objNum' => $options['objNum'], 'label' => $options['label']);
      break;

    case 'out':
      if (count($o['info']['pages'])) {
        $res = "\n$id 0 obj\n<< /Type /Pages\n/Kids [";
        foreach ($o['info']['pages'] as $v) {
          $res.= "$v 0 R\n";
        }

        $res.= "]\n/Count ".count($this->objects[$id]['info']['pages']);

        if ( (isset($o['info']['fonts']) && count($o['info']['fonts'])) ||
              isset($o['info']['procset']) ||
              (isset($o['info']['extGStates']) && count($o['info']['extGStates']))) {
          $res.= "\n/Resources <<";

          if (isset($o['info']['procset'])) {
            $res.= "\n/ProcSet ".$o['info']['procset']." 0 R";
          }

          if (isset($o['info']['fonts']) && count($o['info']['fonts'])) {
            $res.= "\n/Font << ";
            foreach ($o['info']['fonts'] as $finfo) {
              $res.= "\n/F".$finfo['fontNum']." ".$finfo['objNum']." 0 R";
            }
            $res.= "\n>>";
          }

          if (isset($o['info']['xObjects']) && count($o['info']['xObjects'])) {
            $res.= "\n/XObject << ";
            foreach ($o['info']['xObjects'] as $finfo) {
              $res.= "\n/".$finfo['label']." ".$finfo['objNum']." 0 R";
            }
            $res.= "\n>>";
          }

          if ( isset($o['info']['extGStates']) && count($o['info']['extGStates'])) {
            $res.= "\n/ExtGState << ";
            foreach ($o['info']['extGStates'] as $gstate) {
              $res.= "\n/GS" . $gstate['stateNum'] . " " . $gstate['objNum'] . " 0 R";
            }
            $res.= "\n>>";
          }

          $res.= "\n>>";
          if (isset($o['info']['mediaBox'])) {
            $tmp = $o['info']['mediaBox'];
            $res.= "\n/MediaBox [".sprintf('%.3F %.3F %.3F %.3F', $tmp[0], $tmp[1], $tmp[2], $tmp[3]) .']';
          }
        }

        $res.= "\n >>\nendobj";
      }
      else {
        $res = "\n$id 0 obj\n<< /Type /Pages\n/Count 0\n>>\nendobj";
      }

      return $res;
    }
  }

  /**
   * define the outlines in the doc, empty for now
   */
  protected function o_outlines($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = &$this->objects[$id];
    }

    switch ($action) {
      case 'new':
        $this->objects[$id] = array('t' => 'outlines', 'info' => array('outlines' => array()));
        $this->o_catalog($this->catalogId, 'outlines', $id);
        break;

      case 'outline':
        $o['info']['outlines'][] = $options;
        break;

      case 'out':
        if (count($o['info']['outlines'])) {
          $res = "\n$id 0 obj\n<< /Type /Outlines /Kids [";
          foreach ($o['info']['outlines'] as $v) {
            $res.= "$v 0 R ";
          }

          $res.= "] /Count ".count($o['info']['outlines']) ." >>\nendobj";
        } else {
          $res = "\n$id 0 obj\n<< /Type /Outlines /Count 0 >>\nendobj";
        }

        return $res;
    }
  }

  /**
   * an object to hold the font description
   */
  protected function o_font($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = &$this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'font', 'info' => array('name' => $options['name'], 'fontFileName' => $options['fontFileName'], 'SubType' => 'Type1'));
      $fontNum = $this->numFonts;
      $this->objects[$id]['info']['fontNum'] = $fontNum;

      // deal with the encoding and the differences
      if (isset($options['differences'])) {
        // then we'll need an encoding dictionary
        $this->numObj++;
        $this->o_fontEncoding($this->numObj, 'new', $options);
        $this->objects[$id]['info']['encodingDictionary'] = $this->numObj;
      }
      else if (isset($options['encoding'])) {
        // we can specify encoding here
        switch ($options['encoding']) {
          case 'WinAnsiEncoding':
          case 'MacRomanEncoding':
          case 'MacExpertEncoding':
            $this->objects[$id]['info']['encoding'] = $options['encoding'];
            break;

          case 'none':
            break;

          default:
            $this->objects[$id]['info']['encoding'] = 'WinAnsiEncoding';
            break;
        }
      }
      else {
        $this->objects[$id]['info']['encoding'] = 'WinAnsiEncoding';
      }

      if ($this->fonts[$options['fontFileName']]['isUnicode']) {
        // For Unicode fonts, we need to incorporate font data into
        // sub-sections that are linked from the primary font section.
        // Look at o_fontGIDtoCID and o_fontDescendentCID functions
        // for more informaiton.
        //
        // All of this code is adapted from the excellent changes made to
        // transform FPDF to TCPDF (http://tcpdf.sourceforge.net/)

        $toUnicodeId = ++$this->numObj;
        $this->o_contents($toUnicodeId, 'new', 'raw');
        $this->objects[$id]['info']['toUnicode'] = $toUnicodeId;

        $stream = <<<EOT
/CIDInit /ProcSet findresource begin
12 dict begin
begincmap
/CIDSystemInfo
<</Registry (Adobe)
/Ordering (UCS)
/Supplement 0
>> def
/CMapName /Adobe-Identity-UCS def
/CMapType 2 def
1 begincodespacerange
<0000> <FFFF>
endcodespacerange
1 beginbfrange
<0000> <FFFF> <0000>
endbfrange
endcmap
CMapName currentdict /CMap defineresource pop
end
end
EOT;

        $res = "<</Length " . mb_strlen($stream, '8bit') . " >>\n";
        $res .= "stream\n" . $stream . "\nendstream";

        $this->objects[$toUnicodeId]['c'] = $res;

        $cidFontId = ++$this->numObj;
        $this->o_fontDescendentCID($cidFontId, 'new', $options);
        $this->objects[$id]['info']['cidFont'] = $cidFontId;
      }

      // also tell the pages node about the new font
      $this->o_pages($this->currentNode, 'font', array('fontNum' => $fontNum, 'objNum' => $id));
      break;

    case 'add':
      foreach ($options as $k => $v) {
        switch ($k) {
          case 'BaseFont':
            $o['info']['name'] = $v;
            break;
          case 'FirstChar':
          case 'LastChar':
          case 'Widths':
          case 'FontDescriptor':
          case 'SubType':
            $this->addMessage('o_font '.$k." : ".$v);
            $o['info'][$k] = $v;
            break;
        }
      }

      // pass values down to descendent font
      if (isset($o['info']['cidFont'])) {
        $this->o_fontDescendentCID($o['info']['cidFont'], 'add', $options);
      }
      break;

    case 'out':
      if ($this->fonts[$this->objects[$id]['info']['fontFileName']]['isUnicode']) {
        // For Unicode fonts, we need to incorporate font data into
        // sub-sections that are linked from the primary font section.
        // Look at o_fontGIDtoCID and o_fontDescendentCID functions
        // for more informaiton.
        //
        // All of this code is adapted from the excellent changes made to
        // transform FPDF to TCPDF (http://tcpdf.sourceforge.net/)

        $res = "\n$id 0 obj\n<</Type /Font\n/Subtype /Type0\n";
        $res.= "/BaseFont /".$o['info']['name']."\n";

        // The horizontal identity mapping for 2-byte CIDs; may be used
        // with CIDFonts using any Registry, Ordering, and Supplement values.
        $res.= "/Encoding /Identity-H\n";
        $res.= "/DescendantFonts [".$o['info']['cidFont']." 0 R]\n";
        $res.= "/ToUnicode ".$o['info']['toUnicode']." 0 R\n";
        $res.= ">>\n";
        $res.= "endobj";
      } else {
        $res = "\n$id 0 obj\n<< /Type /Font\n/Subtype /".$o['info']['SubType']."\n";
        $res.= "/Name /F".$o['info']['fontNum']."\n";
        $res.= "/BaseFont /".$o['info']['name']."\n";

        if (isset($o['info']['encodingDictionary'])) {
          // then place a reference to the dictionary
          $res.= "/Encoding ".$o['info']['encodingDictionary']." 0 R\n";
        } else if (isset($o['info']['encoding'])) {
          // use the specified encoding
          $res.= "/Encoding /".$o['info']['encoding']."\n";
        }

        if (isset($o['info']['FirstChar'])) {
          $res.= "/FirstChar ".$o['info']['FirstChar']."\n";
        }

        if (isset($o['info']['LastChar'])) {
          $res.= "/LastChar ".$o['info']['LastChar']."\n";
        }

        if (isset($o['info']['Widths'])) {
          $res.= "/Widths ".$o['info']['Widths']." 0 R\n";
        }

        if (isset($o['info']['FontDescriptor'])) {
          $res.= "/FontDescriptor ".$o['info']['FontDescriptor']." 0 R\n";
        }

        $res.= ">>\n";
        $res.= "endobj";
      }

      return $res;
    }
  }

  /**
   * a font descriptor, needed for including additional fonts
   */
  protected function o_fontDescriptor($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
      case 'new':
        $this->objects[$id] = array('t' => 'fontDescriptor', 'info' => $options);
        break;

      case 'out':
        $res = "\n$id 0 obj\n<< /Type /FontDescriptor\n";
        foreach ($o['info'] as $label => $value) {
          switch ($label) {
          case 'Ascent':
          case 'CapHeight':
          case 'Descent':
          case 'Flags':
          case 'ItalicAngle':
          case 'StemV':
          case 'AvgWidth':
          case 'Leading':
          case 'MaxWidth':
          case 'MissingWidth':
          case 'StemH':
          case 'XHeight':
          case 'CharSet':
            if (mb_strlen($value, '8bit')) {
              $res.= "/$label $value\n";
            }

            break;
          case 'FontFile':
          case 'FontFile2':
          case 'FontFile3':
            $res.= "/$label $value 0 R\n";
            break;

          case 'FontBBox':
            $res.= "/$label [$value[0] $value[1] $value[2] $value[3]]\n";
            break;

          case 'FontName':
            $res.= "/$label /$value\n";
            break;
          }
        }

        $res.= ">>\nendobj";

        return $res;
    }
  }

  /**
   * the font encoding
   */
  protected function o_fontEncoding($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      // the options array should contain 'differences' and maybe 'encoding'
      $this->objects[$id] = array('t' => 'fontEncoding', 'info' => $options);
      break;

    case 'out':
      $res = "\n$id 0 obj\n<< /Type /Encoding\n";
      if (!isset($o['info']['encoding'])) {
        $o['info']['encoding'] = 'WinAnsiEncoding';
      }

      if ($o['info']['encoding'] !== 'none') {
        $res.= "/BaseEncoding /".$o['info']['encoding']."\n";
      }

      $res.= "/Differences \n[";

      $onum = -100;

      foreach ($o['info']['differences'] as $num => $label) {
        if ($num != $onum+1) {
          // we cannot make use of consecutive numbering
          $res.= "\n$num /$label";
        } else {
          $res.= " /$label";
        }

        $onum = $num;
      }

      $res.= "\n]\n>>\nendobj";
      return $res;
    }
  }

  /**
   * a descendent cid font, needed for unicode fonts
   */
  protected function o_fontDescendentCID($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'fontDescendentCID', 'info' => $options);

      // we need a CID system info section
      $cidSystemInfoId = ++$this->numObj;
      $this->o_contents($cidSystemInfoId, 'new', 'raw');
      $this->objects[$id]['info']['cidSystemInfo'] = $cidSystemInfoId;
      $res = "<</Registry (Adobe)\n"; // A string identifying an issuer of character collections
      $res.= "/Ordering (UCS)\n"; // A string that uniquely names a character collection issued by a specific registry
      $res.= "/Supplement 0\n"; // The supplement number of the character collection.
      $res.= ">>";
      $this->objects[$cidSystemInfoId]['c'] = $res;

      // and a CID to GID map
      $cidToGidMapId = ++$this->numObj;
      $this->o_fontGIDtoCIDMap($cidToGidMapId, 'new', $options);
      $this->objects[$id]['info']['cidToGidMap'] = $cidToGidMapId;
      break;

    case 'add':
      foreach ($options as $k => $v) {
        switch ($k) {
        case 'BaseFont':
          $o['info']['name'] = $v;
          break;

        case 'FirstChar':
        case 'LastChar':
        case 'MissingWidth':
        case 'FontDescriptor':
        case 'SubType':
          $this->addMessage("o_fontDescendentCID $k : $v");
          $o['info'][$k] = $v;
          break;
        }
      }

      // pass values down to cid to gid map
      $this->o_fontGIDtoCIDMap($o['info']['cidToGidMap'], 'add', $options);
      break;

    case 'out':
      $res = "\n$id 0 obj\n";
      $res.= "<</Type /Font\n";
      $res.= "/Subtype /CIDFontType2\n";
      $res.= "/BaseFont /".$o['info']['name']."\n";
      $res.= "/CIDSystemInfo ".$o['info']['cidSystemInfo']." 0 R\n";
//      if (isset($o['info']['FirstChar'])) {
//        $res.= "/FirstChar ".$o['info']['FirstChar']."\n";
//      }

//      if (isset($o['info']['LastChar'])) {
//        $res.= "/LastChar ".$o['info']['LastChar']."\n";
//      }
      if (isset($o['info']['FontDescriptor'])) {
        $res.= "/FontDescriptor ".$o['info']['FontDescriptor']." 0 R\n";
      }

      if (isset($o['info']['MissingWidth'])) {
        $res.= "/DW ".$o['info']['MissingWidth']."\n";
      }

      if (isset($o['info']['fontFileName']) && isset($this->fonts[$o['info']['fontFileName']]['CIDWidths'])) {
        $cid_widths = &$this->fonts[$o['info']['fontFileName']]['CIDWidths'];
        $w = '';
        foreach ($cid_widths as $cid => $width) {
          $w .= "$cid [$width] ";
        }
        $res.= "/W [$w]\n";
      }

      $res.= "/CIDToGIDMap ".$o['info']['cidToGidMap']." 0 R\n";
      $res.= ">>\n";
      $res.= "endobj";

      return $res;
    }
  }

  /**
   * a font glyph to character map, needed for unicode fonts
   */
  protected function o_fontGIDtoCIDMap($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'fontGIDtoCIDMap', 'info' => $options);
      break;

    case 'out':
      $res = "\n$id 0 obj\n";
      $fontFileName = $o['info']['fontFileName'];
      $tmp = $this->fonts[$fontFileName]['CIDtoGID'] = base64_decode($this->fonts[$fontFileName]['CIDtoGID']);

      $compressed = isset($this->fonts[$fontFileName]['CIDtoGID_Compressed']) &&
                    $this->fonts[$fontFileName]['CIDtoGID_Compressed'];

      if (!$compressed && isset($o['raw'])) {
        $res.= $tmp;
      } else {
        $res.= "<<";

        if (!$compressed && $this->compressionReady && $this->options['compression']) {
          // then implement ZLIB based compression on this content stream
          $compressed = true;
          $tmp = gzcompress($tmp, 6);
        }
        if ($compressed) {
          $res.= "\n/Filter /FlateDecode";
        }

        $res.= "\n/Length ".mb_strlen($tmp, '8bit') .">>\nstream\n$tmp\nendstream";
      }

      $res.= "\nendobj";
      return $res;
    }
  }

  /**
   * the document procset, solves some problems with printing to old PS printers
   */
  protected function o_procset($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
      case 'new':
        $this->objects[$id] = array('t' => 'procset', 'info' => array('PDF' => 1, 'Text' => 1));
        $this->o_pages($this->currentNode, 'procset', $id);
        $this->procsetObjectId = $id;
        break;

      case 'add':
        // this is to add new items to the procset list, despite the fact that this is considered
        // obselete, the items are required for printing to some postscript printers
        switch ($options) {
        case 'ImageB':
        case 'ImageC':
        case 'ImageI':
          $o['info'][$options] = 1;
          break;
        }
        break;

      case 'out':
        $res = "\n$id 0 obj\n[";
        foreach ($o['info'] as $label => $val) {
          $res.= "/$label ";
        }
        $res.= "]\nendobj";
        return $res;
    }
  }

  /**
   * define the document information
   */
  protected function o_info($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
      case 'new':
        $this->infoObject = $id;
        $date = 'D:'.@date('Ymd');
        $this->objects[$id] = array('t' => 'info', 'info' => array('Creator' => 'R and OS php pdf writer, http://www.ros.co.nz', 'CreationDate' => $date));
        break;
      case 'Title':
      case 'Author':
      case 'Subject':
      case 'Keywords':
      case 'Creator':
      case 'Producer':
      case 'CreationDate':
      case 'ModDate':
      case 'Trapped':
        $o['info'][$action] = $options;
        break;

      case 'out':
        if ($this->encrypted) {
          $this->encryptInit($id);
        }

        $res = "\n$id 0 obj\n<<\n";
        foreach ($o['info'] as $k => $v) {
          $res.= "/$k (";

          if ($this->encrypted) {
            $v = $this->ARC4($v);
          }

          // dates must be outputted as-is, without Unicode transformations
          elseif (!in_array($k, array('CreationDate', 'ModDate'))){
            $v = $this->filterText($v);
          }

          $res.= $v;
          $res.= ")\n";
        }

        $res.= ">>\nendobj";
        return $res;
    }
  }

  /**
   * an action object, used to link to URLS initially
   */
  protected function o_action($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
      case 'new':
        if (is_array($options)) {
          $this->objects[$id] = array('t' => 'action', 'info' => $options, 'type' => $options['type']);
        } else {
          // then assume a URI action
          $this->objects[$id] = array('t' => 'action', 'info' => $options, 'type' => 'URI');
        }
        break;

      case 'out':
        if ($this->encrypted) {
          $this->encryptInit($id);
        }

        $res = "\n$id 0 obj\n<< /Type /Action";
        switch ($o['type']) {
          case 'ilink':
            if (!isset($this->destinations[(string)$o['info']['label']])) break;

            // there will be an 'label' setting, this is the name of the destination
            $res.= "\n/S /GoTo\n/D ".$this->destinations[(string)$o['info']['label']]." 0 R";
            break;

          case 'URI':
            $res.= "\n/S /URI\n/URI (";
            if ($this->encrypted) {
              $res.= $this->filterText($this->ARC4($o['info']), true, false);
            } else {
              $res.= $this->filterText($o['info'], true, false);
            }

            $res.= ")";
            break;
        }

        $res.= "\n>>\nendobj";
        return $res;
    }
  }

  /**
   * an annotation object, this will add an annotation to the current page.
   * initially will support just link annotations
   */
  protected function o_annotation($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
      case 'new':
        // add the annotation to the current page
        $pageId = $this->currentPage;
        $this->o_page($pageId, 'annot', $id);

        // and add the action object which is going to be required
        switch ($options['type']) {
          case 'link':
            $this->objects[$id] = array('t' => 'annotation', 'info' => $options);
            $this->numObj++;
            $this->o_action($this->numObj, 'new', $options['url']);
            $this->objects[$id]['info']['actionId'] = $this->numObj;
            break;

          case 'ilink':
            // this is to a named internal link
            $label = $options['label'];
            $this->objects[$id] = array('t' => 'annotation', 'info' => $options);
            $this->numObj++;
            $this->o_action($this->numObj, 'new', array('type' => 'ilink', 'label' => $label));
            $this->objects[$id]['info']['actionId'] = $this->numObj;
            break;
        }
        break;

      case 'out':
        $res = "\n$id 0 obj\n<< /Type /Annot";
        switch ($o['info']['type']) {
          case 'link':
          case 'ilink':
            $res.= "\n/Subtype /Link";
            break;
        }
        $res.= "\n/A ".$o['info']['actionId']." 0 R";
        $res.= "\n/Border [0 0 0]";
        $res.= "\n/H /I";
        $res.= "\n/Rect [ ";

        foreach ($o['info']['rect'] as $v) {
          $res.= sprintf("%.4F ", $v);
        }

        $res.= "]";
        $res.= "\n>>\nendobj";
        return $res;
    }
  }

  /**
   * a page object, it also creates a contents object to hold its contents
   */
  protected function o_page($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->numPages++;
      $this->objects[$id] = array('t' => 'page', 'info' => array('parent' => $this->currentNode, 'pageNum' => $this->numPages));

      if (is_array($options)) {
        // then this must be a page insertion, array should contain 'rid','pos'=[before|after]
        $options['id'] = $id;
        $this->o_pages($this->currentNode, 'page', $options);
      } else {
        $this->o_pages($this->currentNode, 'page', $id);
      }

      $this->currentPage = $id;
      //make a contents object to go with this page
      $this->numObj++;
      $this->o_contents($this->numObj, 'new', $id);
      $this->currentContents = $this->numObj;
      $this->objects[$id]['info']['contents'] = array();
      $this->objects[$id]['info']['contents'][] = $this->numObj;

      $match = ($this->numPages%2 ? 'odd' : 'even');
      foreach ($this->addLooseObjects as $oId => $target) {
        if ($target === 'all' || $match === $target) {
          $this->objects[$id]['info']['contents'][] = $oId;
        }
      }
      break;

    case 'content':
      $o['info']['contents'][] = $options;
      break;

    case 'annot':
      // add an annotation to this page
      if (!isset($o['info']['annot'])) {
        $o['info']['annot'] = array();
      }

      // $options should contain the id of the annotation dictionary
      $o['info']['annot'][] = $options;
      break;

    case 'out':
      $res = "\n$id 0 obj\n<< /Type /Page";
      $res.= "\n/Parent ".$o['info']['parent']." 0 R";

      if (isset($o['info']['annot'])) {
        $res.= "\n/Annots [";
        foreach ($o['info']['annot'] as $aId) {
          $res.= " $aId 0 R";
        }
        $res.= " ]";
      }

      $count = count($o['info']['contents']);
      if ($count == 1) {
        $res.= "\n/Contents ".$o['info']['contents'][0]." 0 R";
      } else if ($count > 1) {
        $res.= "\n/Contents [\n";

        // reverse the page contents so added objects are below normal content
        //foreach (array_reverse($o['info']['contents']) as $cId) {
        // Back to normal now that I've got transparency working --Benj
        foreach ($o['info']['contents'] as $cId) {
          $res.= "$cId 0 R\n";
        }
        $res.= "]";
      }

      $res.= "\n>>\nendobj";
      return $res;
    }
  }

  /**
   * the contents objects hold all of the content which appears on pages
   */
  protected function o_contents($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'contents', 'c' => '', 'info' => array());
      if (mb_strlen($options, '8bit') && intval($options)) {
        // then this contents is the primary for a page
        $this->objects[$id]['onPage'] = $options;
      } else if ($options === 'raw') {
        // then this page contains some other type of system object
        $this->objects[$id]['raw'] = 1;
      }
      break;

    case 'add':
      // add more options to the decleration
      foreach ($options as $k => $v) {
        $o['info'][$k] = $v;
      }

    case 'out':
      $tmp = $o['c'];
      $res = "\n$id 0 obj\n";

      if (isset($this->objects[$id]['raw'])) {
        $res.= $tmp;
      } else {
        $res.= "<<";
        if ($this->compressionReady && $this->options['compression']) {
          // then implement ZLIB based compression on this content stream
          $res.= " /Filter /FlateDecode";
          $tmp = gzcompress($tmp, 6);
        }

        if ($this->encrypted) {
          $this->encryptInit($id);
          $tmp = $this->ARC4($tmp);
        }

        foreach ($o['info'] as $k => $v) {
          $res.= "\n/$k $v";
        }

        $res.= "\n/Length ".mb_strlen($tmp, '8bit') ." >>\nstream\n$tmp\nendstream";
      }

      $res.= "\nendobj";
      return $res;
    }
  }

  protected function o_embedjs($id, $action) {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'embedjs', 'info' => array(
        'Names' => '[(EmbeddedJS) '.($id+1).' 0 R]'
      ));
      break;

    case 'out':
      $res = "\n$id 0 obj\n<< ";
      foreach ($o['info'] as $k => $v) {
        $res.= "\n/$k $v";
      }
      $res.= "\n>>\nendobj";
      return $res;
    }
  }

  protected function o_javascript($id, $action, $code = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      $this->objects[$id] = array('t' => 'javascript', 'info' => array(
        'S' => '/JavaScript',
        'JS' => '('.$this->filterText($code).')',
      ));
      break;

    case 'out':
      $res = "\n$id 0 obj\n<< ";
      foreach ($o['info'] as $k => $v) {
        $res.= "\n/$k $v";
      }
      $res.= "\n>>\nendobj";
      return $res;
    }
  }

  /**
   * an image object, will be an XObject in the document, includes description and data
   */
  protected function o_image($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      // make the new object
      $this->objects[$id] = array('t' => 'image', 'data' => &$options['data'], 'info' => array());

      $info =& $this->objects[$id]['info'];

      $info['Type'] = '/XObject';
      $info['Subtype'] = '/Image';
      $info['Width'] = $options['iw'];
      $info['Height'] = $options['ih'];

      if (isset($options['masked']) && $options['masked']) {
        $info['SMask'] = ($this->numObj-1).' 0 R';
      }

      if (!isset($options['type']) || $options['type'] === 'jpg') {
        if (!isset($options['channels'])) {
          $options['channels'] = 3;
        }

        switch ($options['channels']) {
          case  1: $info['ColorSpace'] = '/DeviceGray'; break;
          case  4: $info['ColorSpace'] = '/DeviceCMYK'; break;
          default: $info['ColorSpace'] = '/DeviceRGB'; break;
        }

        if ($info['ColorSpace'] === '/DeviceCMYK') {
          $info['Decode'] = '[1 0 1 0 1 0 1 0]';
        }

        $info['Filter'] = '/DCTDecode';
        $info['BitsPerComponent'] = 8;
      } 

      else if ($options['type'] === 'png') {
        $info['Filter'] = '/FlateDecode';
        $info['DecodeParms'] = '<< /Predictor 15 /Colors '.$options['ncolor'].' /Columns '.$options['iw'].' /BitsPerComponent '.$options['bitsPerComponent'].'>>';

        if ($options['isMask']) {
          $info['ColorSpace'] = '/DeviceGray';
        }
        else {
          if (mb_strlen($options['pdata'], '8bit')) {
            $tmp = ' [ /Indexed /DeviceRGB '.(mb_strlen($options['pdata'], '8bit') /3-1) .' ';
            $this->numObj++;
            $this->o_contents($this->numObj, 'new');
            $this->objects[$this->numObj]['c'] = $options['pdata'];
            $tmp.= $this->numObj.' 0 R';
            $tmp.= ' ]';
            $info['ColorSpace'] = $tmp;

            if (isset($options['transparency'])) {
              $transparency = $options['transparency'];
              switch ($transparency['type']) {
              case 'indexed':
                $tmp = ' [ '.$transparency['data'].' '.$transparency['data'].'] ';
                $info['Mask'] = $tmp;
                break;

              case 'color-key':
                $tmp = ' [ '.
                  $transparency['r'] . ' ' . $transparency['r'] .
                  $transparency['g'] . ' ' . $transparency['g'] .
                  $transparency['b'] . ' ' . $transparency['b'] .
                  ' ] ';
                $info['Mask'] = $tmp;
                break;
              }
            }
          } else {
            if (isset($options['transparency'])) {
              $transparency = $options['transparency'];

              switch ($transparency['type']) {
              case 'indexed':
                $tmp = ' [ '.$transparency['data'].' '.$transparency['data'].'] ';
                $info['Mask'] = $tmp;
                break;

              case 'color-key':
                $tmp = ' [ '.
                  $transparency['r'] . ' ' . $transparency['r'] . ' ' .
                  $transparency['g'] . ' ' . $transparency['g'] . ' ' .
                  $transparency['b'] . ' ' . $transparency['b'] .
                  ' ] ';
                $info['Mask'] = $tmp;
                break;
              }
            }
            $info['ColorSpace'] = '/'.$options['color'];
          }
        }

        $info['BitsPerComponent'] = $options['bitsPerComponent'];
      }

      // assign it a place in the named resource dictionary as an external object, according to
      // the label passed in with it.
      $this->o_pages($this->currentNode, 'xObject', array('label' => $options['label'], 'objNum' => $id));

      // also make sure that we have the right procset object for it.
      $this->o_procset($this->procsetObjectId, 'add', 'ImageC');
      break;

    case 'out':
      $tmp = &$o['data'];
      $res = "\n$id 0 obj\n<<";

      foreach ($o['info'] as $k => $v) {
        $res.= "\n/$k $v";
      }

      if ($this->encrypted) {
        $this->encryptInit($id);
        $tmp = $this->ARC4($tmp);
      }

      $res.= "\n/Length ".mb_strlen($tmp, '8bit') .">>\nstream\n$tmp\nendstream\nendobj";

      return $res;
    }
  }

  /**
   * graphics state object
   */
  protected function o_extGState($id, $action, $options = "") {
    static $valid_params = array("LW",  "LC",  "LC",  "LJ",  "ML",
                                   "D",  "RI",  "OP",  "op",  "OPM",
                                   "Font",  "BG",  "BG2",  "UCR",
                                   "TR",  "TR2",  "HT",  "FL",
                                   "SM",  "SA",  "BM",  "SMask",
                                   "CA",  "ca",  "AIS",  "TK");

    if ($action !== "new") {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case "new":
      $this->objects[$id] = array('t' => 'extGState', 'info' => $options);

      // Tell the pages about the new resource
      $this->numStates++;
      $this->o_pages($this->currentNode, 'extGState', array("objNum" => $id, "stateNum" => $this->numStates));
      break;

    case "out":
      $res = "\n$id 0 obj\n<< /Type /ExtGState\n";

      foreach ($o["info"] as $k => $v) {
        if ( !in_array($k, $valid_params))
          continue;
        $res.= "/$k $v\n";
      }

      $res.= ">>\nendobj";
      return $res;
    }
  }

  /**
   * encryption object.
   */
  protected function o_encryption($id, $action, $options = '') {
    if ($action !== 'new') {
      $o = & $this->objects[$id];
    }

    switch ($action) {
    case 'new':
      // make the new object
      $this->objects[$id] = array('t' => 'encryption', 'info' => $options);
      $this->arc4_objnum = $id;

      // figure out the additional paramaters required
      $pad = chr(0x28) .chr(0xBF) .chr(0x4E) .chr(0x5E) .chr(0x4E) .chr(0x75) .chr(0x8A) .chr(0x41)
             .chr(0x64) .chr(0x00) .chr(0x4E) .chr(0x56) .chr(0xFF) .chr(0xFA) .chr(0x01) .chr(0x08)
             .chr(0x2E) .chr(0x2E) .chr(0x00) .chr(0xB6) .chr(0xD0) .chr(0x68) .chr(0x3E) .chr(0x80)
             .chr(0x2F) .chr(0x0C) .chr(0xA9) .chr(0xFE) .chr(0x64) .chr(0x53) .chr(0x69) .chr(0x7A);

      $len = mb_strlen($options['owner'], '8bit');

      if ($len > 32) {
        $owner = substr($options['owner'], 0, 32);
      } else if ($len < 32) {
        $owner = $options['owner'].substr($pad, 0, 32-$len);
      } else {
        $owner = $options['owner'];
      }

      $len = mb_strlen($options['user'], '8bit');
      if ($len > 32) {
        $user = substr($options['user'], 0, 32);
      } else if ($len < 32) {
        $user = $options['user'].substr($pad, 0, 32-$len);
      } else {
        $user = $options['user'];
      }

      $tmp = $this->md5_16($owner);
      $okey = substr($tmp, 0, 5);
      $this->ARC4_init($okey);
      $ovalue = $this->ARC4($user);
      $this->objects[$id]['info']['O'] = $ovalue;

      // now make the u value, phew.
      $tmp = $this->md5_16($user.$ovalue.chr($options['p']) .chr(255) .chr(255) .chr(255) .$this->fileIdentifier);

      $ukey = substr($tmp, 0, 5);
      $this->ARC4_init($ukey);
      $this->encryptionKey = $ukey;
      $this->encrypted = true;
      $uvalue = $this->ARC4($pad);
      $this->objects[$id]['info']['U'] = $uvalue;
      $this->encryptionKey = $ukey;
      // initialize the arc4 array
      break;

    case 'out':
      $res = "\n$id 0 obj\n<<";
      $res.= "\n/Filter /Standard";
      $res.= "\n/V 1";
      $res.= "\n/R 2";
      $res.= "\n/O (".$this->filterText($o['info']['O'], true, false) .')';
      $res.= "\n/U (".$this->filterText($o['info']['U'], true, false) .')';
      // and the p-value needs to be converted to account for the twos-complement approach
      $o['info']['p'] = (($o['info']['p']^255) +1) *-1;
      $res.= "\n/P ".($o['info']['p']);
      $res.= "\n>>\nendobj";
      return $res;
    }
  }

  /**
   * ARC4 functions
   * A series of function to implement ARC4 encoding in PHP
   */

  /**
   * calculate the 16 byte version of the 128 bit md5 digest of the string
   */
  function md5_16($string) {
    $tmp = md5($string);
    $out = '';
    for ($i = 0; $i <= 30; $i = $i+2) {
      $out.= chr(hexdec(substr($tmp, $i, 2)));
    }
    return $out;
  }

  /**
   * initialize the encryption for processing a particular object
   */
  function encryptInit($id) {
    $tmp = $this->encryptionKey;
    $hex = dechex($id);
    if (mb_strlen($hex, '8bit') < 6) {
      $hex = substr('000000', 0, 6-mb_strlen($hex, '8bit')) .$hex;
    }
    $tmp.= chr(hexdec(substr($hex, 4, 2))) .chr(hexdec(substr($hex, 2, 2))) .chr(hexdec(substr($hex, 0, 2))) .chr(0) .chr(0);
    $key = $this->md5_16($tmp);
    $this->ARC4_init(substr($key, 0, 10));
  }

  /**
   * initialize the ARC4 encryption
   */
  function ARC4_init($key = '') {
    $this->arc4 = '';

    // setup the control array
    if (mb_strlen($key, '8bit') == 0) {
      return;
    }

    $k = '';
    while (mb_strlen($k, '8bit') < 256) {
      $k.= $key;
    }

    $k = substr($k, 0, 256);
    for ($i = 0; $i < 256; $i++) {
      $this->arc4.= chr($i);
    }

    $j = 0;

    for ($i = 0; $i < 256; $i++) {
      $t = $this->arc4[$i];
      $j = ($j + ord($t) + ord($k[$i])) %256;
      $this->arc4[$i] = $this->arc4[$j];
      $this->arc4[$j] = $t;
    }
  }

  /**
   * ARC4 encrypt a text string
   */
  function ARC4($text) {
    $len = mb_strlen($text, '8bit');
    $a = 0;
    $b = 0;
    $c = $this->arc4;
    $out = '';
    for ($i = 0; $i < $len; $i++) {
      $a = ($a+1) %256;
      $t = $c[$a];
      $b = ($b+ord($t)) %256;
      $c[$a] = $c[$b];
      $c[$b] = $t;
      $k = ord($c[(ord($c[$a]) + ord($c[$b])) %256]);
      $out.= chr(ord($text[$i]) ^ $k);
    }
    return $out;
  }

  /**
   * functions which can be called to adjust or add to the document
   */

  /**
   * add a link in the document to an external URL
   */
  function addLink($url, $x0, $y0, $x1, $y1) {
    $this->numObj++;
    $info = array('type' => 'link', 'url' => $url, 'rect' => array($x0, $y0, $x1, $y1));
    $this->o_annotation($this->numObj, 'new', $info);
  }

  /**
   * add a link in the document to an internal destination (ie. within the document)
   */
  function addInternalLink($label, $x0, $y0, $x1, $y1) {
    $this->numObj++;
    $info = array('type' => 'ilink', 'label' => $label, 'rect' => array($x0, $y0, $x1, $y1));
    $this->o_annotation($this->numObj, 'new', $info);
  }

  /**
   * set the encryption of the document
   * can be used to turn it on and/or set the passwords which it will have.
   * also the functions that the user will have are set here, such as print, modify, add
   */
  function setEncryption($userPass = '', $ownerPass = '', $pc = array()) {
    $p = bindec("11000000");

    $options = array('print' => 4, 'modify' => 8, 'copy' => 16, 'add' => 32);

    foreach ($pc as $k => $v) {
      if ($v && isset($options[$k])) {
        $p+= $options[$k];
      } else if (isset($options[$v])) {
        $p+= $options[$v];
      }
    }

    // implement encryption on the document
    if ($this->arc4_objnum == 0) {
      // then the block does not exist already, add it.
      $this->numObj++;
      if (mb_strlen($ownerPass) == 0) {
        $ownerPass = $userPass;
      }

      $this->o_encryption($this->numObj, 'new', array('user' => $userPass, 'owner' => $ownerPass, 'p' => $p));
    }
  }

  /**
   * should be used for internal checks, not implemented as yet
   */
  function checkAllHere() {
  }

  /**
   * return the pdf stream as a string returned from the function
   */
  function output($debug = false) {
    if ($debug) {
      // turn compression off
      $this->options['compression'] = false;
    }

    if ($this->javascript) {
      $this->numObj++;

      $js_id = $this->numObj;
      $this->o_embedjs($js_id, 'new');
      $this->o_javascript(++$this->numObj, 'new', $this->javascript);

      $id = $this->catalogId;

      $this->o_catalog($id, 'javascript', $js_id);
    }

    if ($this->arc4_objnum) {
      $this->ARC4_init($this->encryptionKey);
    }

    $this->checkAllHere();

    $xref = array();
    $content = '%PDF-1.3';
    $pos = mb_strlen($content, '8bit');

    foreach ($this->objects as $k => $v) {
      $tmp = 'o_'.$v['t'];
      $cont = $this->$tmp($k, 'out');
      $content.= $cont;
      $xref[] = $pos+1; //+1 to account for \n at the start of each object
      $pos+= mb_strlen($cont, '8bit');
    }

    $content.= "\nxref\n0 ".(count($xref) +1) ."\n0000000000 65535 f \n";

    foreach ($xref as $p) {
      $content.= str_pad($p, 10, "0", STR_PAD_LEFT) . " 00000 n \n";
    }

    $content.= "trailer\n<<\n/Size ".(count($xref) +1) ."\n/Root 1 0 R\n/Info $this->infoObject 0 R\n";

    // if encryption has been applied to this document then add the marker for this dictionary
    if ($this->arc4_objnum > 0) {
      $content.= "/Encrypt $this->arc4_objnum 0 R\n";
    }

    if (mb_strlen($this->fileIdentifier, '8bit')) {
      $content.= "/ID[<$this->fileIdentifier><$this->fileIdentifier>]\n";
    }

    // account for \n added at start of xref table
    $pos++;

    $content.= ">>\nstartxref\n$pos\n%%EOF\n";

    return $content;
  }

  /**
   * intialize a new document
   * if this is called on an existing document results may be unpredictable, but the existing document would be lost at minimum
   * this function is called automatically by the constructor function
   */
  private function newDocument($pageSize = array(0, 0, 612, 792)) {
    $this->numObj = 0;
    $this->objects = array();

    $this->numObj++;
    $this->o_catalog($this->numObj, 'new');

    $this->numObj++;
    $this->o_outlines($this->numObj, 'new');

    $this->numObj++;
    $this->o_pages($this->numObj, 'new');

    $this->o_pages($this->numObj, 'mediaBox', $pageSize);
    $this->currentNode = 3;

    $this->numObj++;
    $this->o_procset($this->numObj, 'new');

    $this->numObj++;
    $this->o_info($this->numObj, 'new');

    $this->numObj++;
    $this->o_page($this->numObj, 'new');

    // need to store the first page id as there is no way to get it to the user during
    // startup
    $this->firstPageId = $this->currentContents;
  }

  /**
   * open the font file and return a php structure containing it.
   * first check if this one has been done before and saved in a form more suited to php
   * note that if a php serialized version does not exist it will try and make one, but will
   * require write access to the directory to do it... it is MUCH faster to have these serialized
   * files.
   */
  private function openFont($font) {
    // assume that $font contains the path and file but not the extension
    $pos = strrpos($font, '/');

    if ($pos === false) {
      $dir = './';
      $name = $font;
    } else {
      $dir = substr($font, 0, $pos+1);
      $name = substr($font, $pos+1);
    }

    $fontcache = $this->fontcache;
    if ($fontcache == '') {
      $fontcache = $dir;
    }

    //$name       filename without folder and extension of font metrics
    //$dir      folder of font metrics
    //$fontcache  folder of runtime created php serialized version of font metrics.
    //            If this is not given, the same folder as the font metrics will be used.
    //            Storing and reusing serialized versions improves speed much

    $this->addMessage("openFont: $font - $name");

    if ( !$this->isUnicode || in_array(mb_strtolower(basename($name)), self::$coreFonts) ) {
      $metrics_name = "$name.afm";
    }
    else {
      $metrics_name = "$name.ufm";
    }

    $cache_name = "$metrics_name.php";
    $this->addMessage("metrics: $metrics_name, cache: $cache_name");

    if (file_exists($fontcache . $cache_name)) {
      $this->addMessage("openFont: php file exists $fontcache$cache_name");
      $this->fonts[$font] = require($fontcache . $cache_name);

      if (!isset($this->fonts[$font]['_version_']) || $this->fonts[$font]['_version_'] != $this->fontcacheVersion) {
        // if the font file is old, then clear it out and prepare for re-creation
        $this->addMessage('openFont: clear out, make way for new version.');
        $this->fonts[$font] = null;
        unset($this->fonts[$font]);
      }
    }
    else {
      $old_cache_name = "php_$metrics_name";
      if (file_exists($fontcache . $old_cache_name)) {
        $this->addMessage("openFont: php file doesn't exist $fontcache$cache_name, creating it from the old format");
        $old_cache = file_get_contents($fontcache . $old_cache_name);
        file_put_contents($fontcache . $cache_name, '<?php return ' . $old_cache . ';');
        return $this->openFont($font);
      }
    }

    if (!isset($this->fonts[$font]) && file_exists($dir . $metrics_name)) {
      // then rebuild the php_<font>.afm file from the <font>.afm file
      $this->addMessage("openFont: build php file from $dir$metrics_name");
      $data = array();

      // 20 => 'space'
      $data['codeToName'] = array(); 

      // Since we're not going to enable Unicode for the core fonts we need to use a font-based
      // setting for Unicode support rather than a global setting.
      $data['isUnicode'] = (strtolower(substr($metrics_name, -3)) !== 'afm');

      $cidtogid = '';
      if ($data['isUnicode']) {
        $cidtogid = str_pad('', 256*256*2, "\x00");
      }

      $file = file($dir . $metrics_name);

      foreach ($file as $rowA) {
        $row = trim($rowA);
        $pos = strpos($row, ' ');

        if ($pos) {
          // then there must be some keyword
          $key = substr($row, 0, $pos);
          switch ($key) {
          case 'FontName':
          case 'FullName':
          case 'FamilyName':
          case 'PostScriptName':
          case 'Weight':
          case 'ItalicAngle':
          case 'IsFixedPitch':
          case 'CharacterSet':
          case 'UnderlinePosition':
          case 'UnderlineThickness':
          case 'Version':
          case 'EncodingScheme':
          case 'CapHeight':
          case 'XHeight':
          case 'Ascender':
          case 'Descender':
          case 'StdHW':
          case 'StdVW':
          case 'StartCharMetrics':
          case 'FontHeightOffset': // OAR - Added so we can offset the height calculation of a Windows font.  Otherwise it's too big.
            $data[$key] = trim(substr($row, $pos));
            break;

          case 'FontBBox':
            $data[$key] = explode(' ', trim(substr($row, $pos)));
            break;

          //C 39 ; WX 222 ; N quoteright ; B 53 463 157 718 ;
          case 'C': // Found in AFM files
            $bits = explode(';', trim($row));
            $dtmp = array();

            foreach ($bits as $bit) {
              $bits2 = explode(' ', trim($bit));
              if (mb_strlen($bits2[0], '8bit') == 0) continue;

              if (count($bits2) > 2) {
                $dtmp[$bits2[0]] = array();
                for ($i = 1; $i < count($bits2); $i++) {
                  $dtmp[$bits2[0]][] = $bits2[$i];
                }
              } else if (count($bits2) == 2) {
                $dtmp[$bits2[0]] = $bits2[1];
              }
            }

            $c = (int)$dtmp['C'];
            $n = $dtmp['N'];
            $width = floatval($dtmp['WX']);

            if ($c >= 0) {
              if ($c != hexdec($n)) {
                $data['codeToName'][$c] = $n;
              }
              $data['C'][$c] = $width;
            } else {
              $data['C'][$n] = $width;
            }

            if (!isset($data['MissingWidth']) && $c == -1 && $n === '.notdef') {
              $data['MissingWidth'] = $width;
            }

            break;

          // U 827 ; WX 0 ; N squaresubnosp ; G 675 ;
          case 'U': // Found in UFM files
            if (!$data['isUnicode']) break;

            $bits = explode(';', trim($row));
            $dtmp = array();

            foreach ($bits as $bit) {
              $bits2 = explode(' ', trim($bit));
              if (mb_strlen($bits2[0], '8bit') === 0) continue;

              if (count($bits2) > 2) {
                $dtmp[$bits2[0]] = array();
                for ($i = 1; $i < count($bits2); $i++) {
                  $dtmp[$bits2[0]][] = $bits2[$i];
                }
              } else if (count($bits2) == 2) {
                $dtmp[$bits2[0]] = $bits2[1];
              }
            }

            $c = (int)$dtmp['U'];
            $n = $dtmp['N'];
            $glyph = $dtmp['G'];
            $width = floatval($dtmp['WX']);

            if ($c >= 0) {
              // Set values in CID to GID map
              if ($c >= 0 && $c < 0xFFFF && $glyph) {
                $cidtogid[$c*2] = chr($glyph >> 8);
                $cidtogid[$c*2 + 1] = chr($glyph & 0xFF);
              }

              if ($c != hexdec($n)) {
                $data['codeToName'][$c] = $n;
              }
              $data['C'][$c] = $width;
            } else {
              $data['C'][$n] = $width;
            }

            if (!isset($data['MissingWidth']) && $c == -1 && $n === '.notdef') {
              $data['MissingWidth'] = $width;
            }

            break;

          case 'KPX':
            break; // don't include them as they are not used yet
            //KPX Adieresis yacute -40
            $bits = explode(' ', trim($row));
            $data['KPX'][$bits[1]][$bits[2]] = $bits[3];
            break;
          }
        }
      }

      if ($this->compressionReady && $this->options['compression']) {
        // then implement ZLIB based compression on CIDtoGID string
        $data['CIDtoGID_Compressed'] = true;
        $cidtogid = gzcompress($cidtogid, 6);
      }
      $data['CIDtoGID'] = base64_encode($cidtogid);
      $data['_version_'] = $this->fontcacheVersion;
      $this->fonts[$font] = $data;

      //Because of potential trouble with php safe mode, expect that the folder already exists.
      //If not existing, this will hit performance because of missing cached results.
      if ( is_dir(substr($fontcache, 0, -1)) && is_writable(substr($fontcache, 0, -1)) ) {
        file_put_contents($fontcache . $cache_name, '<?php return ' . var_export($data, true) . ';');
      }
      $data = null;
    }

    if (!isset($this->fonts[$font])) {
      $this->addMessage("openFont: no font file found for $font. Do you need to run load_font.php?");
    }

    //pre_r($this->messages);
  }

  /**
   * if the font is not loaded then load it and make the required object
   * else just make it the current font
   * the encoding array can contain 'encoding'=> 'none','WinAnsiEncoding','MacRomanEncoding' or 'MacExpertEncoding'
   * note that encoding='none' will need to be used for symbolic fonts
   * and 'differences' => an array of mappings between numbers 0->255 and character names.
   *
   */
  function selectFont($fontName, $encoding = '', $set = true) {
    $ext = substr($fontName, -4);
    if ($ext === '.afm' || $ext === '.ufm') {
      $fontName = substr($fontName, 0, mb_strlen($fontName)-4);
    }

    if (!isset($this->fonts[$fontName])) {
      $this->addMessage("selectFont: selecting - $fontName - $encoding, $set");

      // load the file
      $this->openFont($fontName);

      if (isset($this->fonts[$fontName])) {
        $this->numObj++;
        $this->numFonts++;

        $font = &$this->fonts[$fontName];

        //$this->numFonts = md5($fontName);
        $pos = strrpos($fontName, '/');
        //      $dir = substr($fontName,0,$pos+1);
        $name = substr($fontName, $pos+1);
        $options = array('name' => $name, 'fontFileName' => $fontName);

        if (is_array($encoding)) {
          // then encoding and differences might be set
          if (isset($encoding['encoding'])) {
            $options['encoding'] = $encoding['encoding'];
          }

          if (isset($encoding['differences'])) {
            $options['differences'] = $encoding['differences'];
          }
        } else if (mb_strlen($encoding, '8bit')) {
          // then perhaps only the encoding has been set
          $options['encoding'] = $encoding;
        }

        $fontObj = $this->numObj;
        $this->o_font($this->numObj, 'new', $options);
        $font['fontNum'] = $this->numFonts;

        // if this is a '.afm' font, and there is a '.pfa' file to go with it ( as there
        // should be for all non-basic fonts), then load it into an object and put the
        // references into the font object
        $basefile = $fontName;

        $fbtype = '';
        if (file_exists("$basefile.pfb")) {
          $fbtype = 'pfb';
        } 
        else if (file_exists("$basefile.ttf")) {
          $fbtype = 'ttf';
        }

        $fbfile = "$basefile.$fbtype";

        //      $pfbfile = substr($fontName,0,strlen($fontName)-4).'.pfb';
        //      $ttffile = substr($fontName,0,strlen($fontName)-4).'.ttf';
        $this->addMessage('selectFont: checking for - '.$fbfile);

        // OAR - I don't understand this old check
        // if (substr($fontName, -4) ===  '.afm' &&  strlen($fbtype)) {
        if ($fbtype) {
          $adobeFontName = isset($font['PostScriptName']) ? $font['PostScriptName'] : $font['FontName'];
          //        $fontObj = $this->numObj;
          $this->addMessage("selectFont: adding font file - $fbfile - $adobeFontName");

          // find the array of font widths, and put that into an object.
          $firstChar = -1;
          $lastChar = 0;
          $widths = array();
          $cid_widths = array();

          foreach ($font['C'] as $num => $d) {
            if (intval($num) > 0 || $num == '0') {
              if (!$font['isUnicode']) {
                // With Unicode, widths array isn't used
                if ($lastChar>0 && $num>$lastChar+1) {
                  for ($i = $lastChar+1; $i<$num; $i++) {
                    $widths[] = 0;
                  }
                }
              }

              $widths[] = $d;

              if ($font['isUnicode']) {
                $cid_widths[$num] = $d;
              }

              if ($firstChar == -1) {
                $firstChar = $num;
              }

              $lastChar = $num;
            }
          }

          // also need to adjust the widths for the differences array
          if (isset($options['differences'])) {
            foreach ($options['differences'] as $charNum => $charName) {
              if ($charNum > $lastChar) {
                if (!$font['isUnicode']) {
                  // With Unicode, widths array isn't used
                  for ($i = $lastChar + 1; $i <= $charNum; $i++) {
                    $widths[] = 0;
                  }
                }

                $lastChar = $charNum;
              }

              if (isset($font['C'][$charName])) {
                $widths[$charNum-$firstChar] = $font['C'][$charName];
                if ($font['isUnicode']) {
                  $cid_widths[$charName] = $font['C'][$charName];
                }
              }
            }
          }

          if ($font['isUnicode']) {
            $font['CIDWidths'] = $cid_widths;
          }

          $this->addMessage('selectFont: FirstChar = '.$firstChar);
          $this->addMessage('selectFont: LastChar = '.$lastChar);

          $widthid = -1;

          if (!$font['isUnicode']) {
            // With Unicode, widths array isn't used

            $this->numObj++;
            $this->o_contents($this->numObj, 'new', 'raw');
            $this->objects[$this->numObj]['c'].= '['.implode(' ', $widths).']';
            $widthid = $this->numObj;
          }

          $missing_width = 500;
          $stemV = 70;

          if (isset($font['MissingWidth'])) {
            $missing_width = $font['MissingWidth'];
          }
          if (isset($font['StdVW'])) {
            $stemV = $font['StdVW'];
          } else if (isset($font['Weight']) && preg_match('!(bold|black)!i', $font['Weight'])) {
            $stemV = 120;
          }

          // load the pfb file, and put that into an object too.
          // note that pdf supports only binary format type 1 font files, though there is a
          // simple utility to convert them from pfa to pfb.
          // FIXME: should we move font subset creation to CPDF::output? See notes in issue #750.
          if (!$this->isUnicode || $fbtype !== 'ttf' || empty($this->stringSubsets)) {
            $data = file_get_contents($fbfile);
          }
          else {
            $this->stringSubsets[$fontName][] = 32; // Force space if not in yet

            $subset = $this->stringSubsets[$fontName];
            sort($subset);

            // Load font
            $font_obj = Font::load($fbfile);
            $font_obj->parse();

            // Define subset
            $font_obj->setSubset($subset);
            $font_obj->reduce();

            // Write new font
            $tmp_name = "$fbfile.tmp.".uniqid();
            $font_obj->open($tmp_name, Font_Binary_Stream::modeWrite);
            $font_obj->encode(array("OS/2"));
            $font_obj->close();

            // Parse the new font to get cid2gid and widths
            $font_obj = Font::load($tmp_name);

            // Find Unicode char map table
            $subtable = null;
            foreach ($font_obj->getData("cmap", "subtables") as $_subtable) {
              if ($_subtable["platformID"] == 0 || $_subtable["platformID"] == 3 && $_subtable["platformSpecificID"] == 1) {
                $subtable = $_subtable;
                break;
              }
            }

            if ($subtable) {
              $glyphIndexArray = $subtable["glyphIndexArray"];
              $hmtx = $font_obj->getData("hmtx");

              unset($glyphIndexArray[0xFFFF]);

              $cidtogid = str_pad('', max(array_keys($glyphIndexArray))*2+1, "\x00");
              $font['CIDWidths'] = array();
              foreach ($glyphIndexArray as $cid => $gid) {
                if ($cid >= 0 && $cid < 0xFFFF && $gid) {
                  $cidtogid[$cid*2] = chr($gid >> 8);
                  $cidtogid[$cid*2 + 1] = chr($gid & 0xFF);
                }

                $width = $font_obj->normalizeFUnit(isset($hmtx[$gid]) ? $hmtx[$gid][0] : $hmtx[0][0]);
                $font['CIDWidths'][$cid] = $width;
              }

              $font['CIDtoGID'] = base64_encode(gzcompress($cidtogid));
              $font['CIDtoGID_Compressed'] = true;

              $data = file_get_contents($tmp_name);
            }
            else {
              $data = file_get_contents($fbfile);
            }

            $font_obj->close();
            unlink($tmp_name);
          }

          // create the font descriptor
          $this->numObj++;
          $fontDescriptorId = $this->numObj;

          $this->numObj++;
          $pfbid = $this->numObj;

          // determine flags (more than a little flakey, hopefully will not matter much)
          $flags = 0;

          if ($font['ItalicAngle'] != 0) {
            $flags+= pow(2, 6);
          }

          if ($font['IsFixedPitch'] === 'true') {
            $flags+= 1;
          }

          $flags+= pow(2, 5); // assume non-sybolic
          $list = array(
            'Ascent' => 'Ascender',
            'CapHeight' => 'Ascender', //FIXME: php-font-lib is not grabbing this value, so we'll fake it and use the Ascender value // 'CapHeight'
            'MissingWidth' => 'MissingWidth',
            'Descent' => 'Descender',
            'FontBBox' => 'FontBBox',
            'ItalicAngle' => 'ItalicAngle'
          );
          $fdopt = array(
            'Flags' => $flags,
            'FontName' => $adobeFontName,
            'StemV' => $stemV
          );

          foreach ($list as $k => $v) {
            if (isset($font[$v])) {
              $fdopt[$k] = $font[$v];
            }
          }

          if ($fbtype === 'pfb') {
            $fdopt['FontFile'] = $pfbid;
          } else if ($fbtype === 'ttf') {
            $fdopt['FontFile2'] = $pfbid;
          }

          $this->o_fontDescriptor($fontDescriptorId, 'new', $fdopt);

          // embed the font program
          $this->o_contents($this->numObj, 'new');
          $this->objects[$pfbid]['c'].= $data;

          // determine the cruicial lengths within this file
          if ($fbtype === 'pfb') {
            $l1 = strpos($data, 'eexec') +6;
            $l2 = strpos($data, '00000000') -$l1;
            $l3 = mb_strlen($data, '8bit') -$l2-$l1;
            $this->o_contents($this->numObj, 'add', array('Length1' => $l1, 'Length2' => $l2, 'Length3' => $l3));
          } else if ($fbtype == 'ttf') {
            $l1 = mb_strlen($data, '8bit');
            $this->o_contents($this->numObj, 'add', array('Length1' => $l1));
          }

          // tell the font object about all this new stuff
          $tmp = array(
            'BaseFont' => $adobeFontName,
            'MissingWidth' => $missing_width,
            'Widths' => $widthid,
            'FirstChar' => $firstChar,
            'LastChar' => $lastChar,
            'FontDescriptor' => $fontDescriptorId
          );

          if ($fbtype === 'ttf') {
            $tmp['SubType'] = 'TrueType';
          }

          $this->addMessage("adding extra info to font.($fontObj)");

          foreach ($tmp as $fk => $fv) {
            $this->addMessage("$fk : $fv");
          }

          $this->o_font($fontObj, 'add', $tmp);
        } else {
          $this->addMessage('selectFont: pfb or ttf file not found, ok if this is one of the 14 standard fonts');
        }

        // also set the differences here, note that this means that these will take effect only the
        //first time that a font is selected, else they are ignored
        if (isset($options['differences'])) {
          $font['differences'] = $options['differences'];
        }
      }
    }

    if ($set && isset($this->fonts[$fontName])) {
      // so if for some reason the font was not set in the last one then it will not be selected
      $this->currentBaseFont = $fontName;

      // the next lines mean that if a new font is selected, then the current text state will be
      // applied to it as well.
      $this->currentFont = $this->currentBaseFont;
      $this->currentFontNum = $this->fonts[$this->currentFont]['fontNum'];

      //$this->setCurrentFont();
    }

    return $this->currentFontNum;
    //return $this->numObj;
  }

  /**
   * sets up the current font, based on the font families, and the current text state
   * note that this system is quite flexible, a bold-italic font can be completely different to a
   * italic-bold font, and even bold-bold will have to be defined within the family to have meaning
   * This function is to be called whenever the currentTextState is changed, it will update
   * the currentFont setting to whatever the appropriatte family one is.
   * If the user calls selectFont themselves then that will reset the currentBaseFont, and the currentFont
   * This function will change the currentFont to whatever it should be, but will not change the
   * currentBaseFont.
   */
  private function setCurrentFont() {
    //   if (strlen($this->currentBaseFont) == 0){
    //     // then assume an initial font
    //     $this->selectFont($this->defaultFont);
    //   }
    //   $cf = substr($this->currentBaseFont,strrpos($this->currentBaseFont,'/')+1);
    //   if (strlen($this->currentTextState)
    //     && isset($this->fontFamilies[$cf])
    //       && isset($this->fontFamilies[$cf][$this->currentTextState])){
    //     // then we are in some state or another
    //     // and this font has a family, and the current setting exists within it
    //     // select the font, then return it
    //     $nf = substr($this->currentBaseFont,0,strrpos($this->currentBaseFont,'/')+1).$this->fontFamilies[$cf][$this->currentTextState];
    //     $this->selectFont($nf,'',0);
    //     $this->currentFont = $nf;
    //     $this->currentFontNum = $this->fonts[$nf]['fontNum'];
    //   } else {
    //     // the this font must not have the right family member for the current state
    //     // simply assume the base font
    $this->currentFont = $this->currentBaseFont;
    $this->currentFontNum = $this->fonts[$this->currentFont]['fontNum'];
    //  }
  }

  /**
   * function for the user to find out what the ID is of the first page that was created during
   * startup - useful if they wish to add something to it later.
   */
  function getFirstPageId() {
    return $this->firstPageId;
  }

  /**
   * add content to the currently active object
   */
  private function addContent($content) {
    $this->objects[$this->currentContents]['c'] .=  $content;
  }

  /**
   * sets the color for fill operations
   */
  function setColor($color, $force = false) {
    $new_color = array($color[0], $color[1], $color[2], isset($color[3]) ? $color[3] : null);

    if (!$force && $this->currentColor == $new_color) {
      return;
    }

    if (isset($new_color[3])) {
      $this->currentColor = $new_color;
      $this->addContent(vsprintf("\n%.3F %.3F %.3F %.3F k", $this->currentColor));
    }

    else if (isset($new_color[2])) {
      $this->currentColor = $new_color;
      $this->addContent(vsprintf("\n%.3F %.3F %.3F rg", $this->currentColor));
    }
  }

  /**
   * sets the color for stroke operations
   */
  function setStrokeColor($color, $force = false) {
    $new_color = array($color[0], $color[1], $color[2], isset($color[3]) ? $color[3] : null);

    if (!$force && $this->currentStrokeColor == $new_color) return;

    if (isset($new_color[3])) {
      $this->currentStrokeColor = $new_color;
      $this->addContent(vsprintf("\n%.3F %.3F %.3F %.3F K", $this->currentStrokeColor));
    }

    else if (isset($new_color[2])) {
      $this->currentStrokeColor = $new_color;
      $this->addContent(vsprintf("\n%.3F %.3F %.3F RG", $this->currentStrokeColor));
    }
  }

  /**
   * Set the graphics state for compositions
   */
  function setGraphicsState($parameters) {
    // Create a new graphics state object
    // FIXME: should actually keep track of states that have already been created...
    $this->numObj++;
    $this->o_extGState($this->numObj, 'new', $parameters);
    $this->addContent("\n/GS$this->numStates gs");
  }

  /**
   * Set current blend mode & opacity for lines.
   *
   * Valid blend modes are:
   *
   * Normal, Multiply, Screen, Overlay, Darken, Lighten,
   * ColorDogde, ColorBurn, HardLight, SoftLight, Difference,
   * Exclusion
   *
   * @param string $mode the blend mode to use
   * @param float $opacity 0.0 fully transparent, 1.0 fully opaque
   */
  function setLineTransparency($mode, $opacity) {
    static $blend_modes = array("Normal", "Multiply", "Screen",
                                "Overlay", "Darken", "Lighten",
                                "ColorDogde", "ColorBurn", "HardLight",
                                "SoftLight", "Difference", "Exclusion");

    if ( !in_array($mode, $blend_modes) )
      $mode = "Normal";

    // Only create a new graphics state if required
    if ( $mode === $this->currentLineTransparency["mode"] &&
         $opacity == $this->currentLineTransparency["opacity"] )
      return;

    $this->currentLineTransparency["mode"] = $mode;
    $this->currentLineTransparency["opacity"] = $opacity;

    $options = array("BM" => "/$mode",
                     "CA" => (float)$opacity);

    $this->setGraphicsState($options);
  }

  /**
   * Set current blend mode & opacity for filled objects.
   *
   * Valid blend modes are:
   *
   * Normal, Multiply, Screen, Overlay, Darken, Lighten,
   * ColorDogde, ColorBurn, HardLight, SoftLight, Difference,
   * Exclusion
   *
   * @param string $mode the blend mode to use
   * @param float $opacity 0.0 fully transparent, 1.0 fully opaque
   */
  function setFillTransparency($mode, $opacity) {
    static $blend_modes = array("Normal", "Multiply", "Screen",
                                "Overlay", "Darken", "Lighten",
                                "ColorDogde", "ColorBurn", "HardLight",
                                "SoftLight", "Difference", "Exclusion");

    if ( !in_array($mode, $blend_modes) ) {
      $mode = "Normal";
    }

    if ( $mode === $this->currentFillTransparency["mode"] &&
         $opacity == $this->currentFillTransparency["opacity"] ) {
      return;
    }

    $this->currentFillTransparency["mode"] = $mode;
    $this->currentFillTransparency["opacity"] = $opacity;

    $options = array(
      "BM" => "/$mode",
      "ca" => (float)$opacity,
    );

    $this->setGraphicsState($options);
  }

  /**
   * draw a line from one set of coordinates to another
   */
  function line($x1, $y1, $x2, $y2, $stroke = true) {
    $this->addContent(sprintf("\n%.3F %.3F m %.3F %.3F l", $x1, $y1, $x2, $y2));

    if ($stroke) {
      $this->addContent(' S');
    }
  }

  /**
   * draw a bezier curve based on 4 control points
   */
  function curve($x0, $y0, $x1, $y1, $x2, $y2, $x3, $y3) {
    // in the current line style, draw a bezier curve from (x0,y0) to (x3,y3) using the other two points
    // as the control points for the curve.
    $this->addContent(sprintf("\n%.3F %.3F m %.3F %.3F %.3F %.3F %.3F %.3F c S", $x0, $y0, $x1, $y1, $x2, $y2, $x3, $y3));
  }

  /**
   * draw a part of an ellipse
   */
  function partEllipse($x0, $y0, $astart, $afinish, $r1, $r2 = 0, $angle = 0, $nSeg = 8) {
    $this->ellipse($x0, $y0, $r1, $r2, $angle, $nSeg, $astart, $afinish, false);
  }

  /**
   * draw a filled ellipse
   */
  function filledEllipse($x0, $y0, $r1, $r2 = 0, $angle = 0, $nSeg = 8, $astart = 0, $afinish = 360) {
    return $this->ellipse($x0, $y0, $r1, $r2, $angle, $nSeg, $astart, $afinish, true, true);
  }

  /**
   * draw an ellipse
   * note that the part and filled ellipse are just special cases of this function
   *
   * draws an ellipse in the current line style
   * centered at $x0,$y0, radii $r1,$r2
   * if $r2 is not set, then a circle is drawn
   * from $astart to $afinish, measured in degrees, running anti-clockwise from the right hand side of the ellipse.
   * nSeg is not allowed to be less than 2, as this will simply draw a line (and will even draw a
   * pretty crappy shape at 2, as we are approximating with bezier curves.
   */
  function ellipse($x0, $y0, $r1, $r2 = 0, $angle = 0, $nSeg = 8, $astart = 0, $afinish = 360, $close = true, $fill = false, $stroke = true, $incomplete = false) {
    if ($r1 == 0) {
      return;
    }

    if ($r2 == 0) {
      $r2 = $r1;
    }

    if ($nSeg < 2) {
      $nSeg = 2;
    }

    $astart = deg2rad((float)$astart);
    $afinish = deg2rad((float)$afinish);
    $totalAngle = $afinish-$astart;

    $dt = $totalAngle/$nSeg;
    $dtm = $dt/3;

    if ($angle != 0) {
      $a = -1*deg2rad((float)$angle);

      $this->addContent(sprintf("\n q %.3F %.3F %.3F %.3F %.3F %.3F cm", cos($a), -sin($a), sin($a), cos($a), $x0, $y0));

      $x0 = 0;
      $y0 = 0;
    }

    $t1 = $astart;
    $a0 = $x0 + $r1*cos($t1);
    $b0 = $y0 + $r2*sin($t1);
    $c0 = -$r1 * sin($t1);
    $d0 = $r2 * cos($t1);

    if (!$incomplete) {
      $this->addContent(sprintf("\n%.3F %.3F m ", $a0, $b0));
    }

    for ($i = 1; $i <= $nSeg; $i++) {
      // draw this bit of the total curve
      $t1 = $i * $dt + $astart;
      $a1 = $x0 + $r1 * cos($t1);
      $b1 = $y0 + $r2 * sin($t1);
      $c1 = -$r1 * sin($t1);
      $d1 = $r2 * cos($t1);

      $this->addContent(sprintf("\n%.3F %.3F %.3F %.3F %.3F %.3F c", ($a0+$c0*$dtm), ($b0+$d0*$dtm), ($a1-$c1*$dtm), ($b1-$d1*$dtm), $a1, $b1));

      $a0 = $a1;
      $b0 = $b1;
      $c0 = $c1;
      $d0 = $d1;
    }

    if (!$incomplete) {
      if ($fill) {
        $this->addContent(' f');
      }
      else if ($close) {
        $this->addContent(' s'); // small 's' signifies closing the path as well
      }
      else if ($stroke) {
        $this->addContent(' S');
      }
    }

    if ($angle != 0) {
      $this->addContent(' Q');
    }
  }

  /**
   * this sets the line drawing style.
   * width, is the thickness of the line in user units
   * cap is the type of cap to put on the line, values can be 'butt','round','square'
   *    where the diffference between 'square' and 'butt' is that 'square' projects a flat end past the
   *    end of the line.
   * join can be 'miter', 'round', 'bevel'
   * dash is an array which sets the dash pattern, is a series of length values, which are the lengths of the
   *   on and off dashes.
   *   (2) represents 2 on, 2 off, 2 on , 2 off ...
   *   (2,1) is 2 on, 1 off, 2 on, 1 off.. etc
   * phase is a modifier on the dash pattern which is used to shift the point at which the pattern starts.
   */
  function setLineStyle($width = 1, $cap = '', $join = '', $dash = '', $phase = 0) {
    // this is quite inefficient in that it sets all the parameters whenever 1 is changed, but will fix another day
    $string = '';

    if ($width > 0) {
      $string.= "$width w";
    }

    $ca = array('butt' => 0, 'round' => 1, 'square' => 2);

    if (isset($ca[$cap])) {
      $string.= " $ca[$cap] J";
    }

    $ja = array('miter' => 0, 'round' => 1, 'bevel' => 2);

    if (isset($ja[$join])) {
      $string.= " $ja[$join] j";
    }

    if (is_array($dash)) {
      $string.= ' [ ' . implode(' ', $dash) . " ] $phase d";
    }

    $this->currentLineStyle = $string;
    $this->addContent("\n$string");
  }

  /**
   * draw a polygon, the syntax for this is similar to the GD polygon command
   */
  function polygon($p, $np, $f = false) {
    $this->addContent(sprintf("\n%.3F %.3F m ", $p[0], $p[1]));

    for ($i = 2; $i < $np * 2; $i = $i + 2) {
      $this->addContent(sprintf("%.3F %.3F l ", $p[$i], $p[$i+1]));
    }

    if ($f) {
      $this->addContent(' f');
    } else {
      $this->addContent(' S');
    }
  }

  /**
   * a filled rectangle, note that it is the width and height of the rectangle which are the secondary paramaters, not
   * the coordinates of the upper-right corner
   */
  function filledRectangle($x1, $y1, $width, $height) {
    $this->addContent(sprintf("\n%.3F %.3F %.3F %.3F re f", $x1, $y1, $width, $height));
  }

  /**
   * draw a rectangle, note that it is the width and height of the rectangle which are the secondary paramaters, not
   * the coordinates of the upper-right corner
   */
  function rectangle($x1, $y1, $width, $height) {
    $this->addContent(sprintf("\n%.3F %.3F %.3F %.3F re S", $x1, $y1, $width, $height));
  }

  /**
   * save the current graphic state
   */
  function save() {
    // we must reset the color cache or it will keep bad colors after clipping
    $this->currentColor = null;
    $this->currentStrokeColor = null;
    $this->addContent("\nq");
  }

  /**
   * restore the last graphic state
   */
  function restore() {
    // we must reset the color cache or it will keep bad colors after clipping
    $this->currentColor = null;
    $this->currentStrokeColor = null;
    $this->addContent("\nQ");
  }

  /**
   * draw a clipping rectangle, all the elements added after this will be clipped
   */
  function clippingRectangle($x1, $y1, $width, $height) {
    $this->save();
    $this->addContent(sprintf("\n%.3F %.3F %.3F %.3F re W n", $x1, $y1, $width, $height));
  }

  /**
   * draw a clipping rounded rectangle, all the elements added after this will be clipped
   */
  function clippingRectangleRounded($x1, $y1, $w, $h, $rTL, $rTR, $rBR, $rBL) {
    $this->save();

    // start: top edge, left end
    $this->addContent(sprintf("\n%.3F %.3F m ", $x1, $y1 - $rTL + $h));

    // curve: bottom-left corner
    $this->ellipse($x1 + $rBL, $y1 + $rBL, $rBL, 0, 0, 8, 180, 270, false, false, false, true);

    // line: right edge, bottom end
    $this->addContent(sprintf("\n%.3F %.3F l ", $x1 + $w - $rBR, $y1));

    // curve: bottom-right corner
    $this->ellipse($x1 + $w - $rBR, $y1 + $rBR, $rBR, 0, 0, 8, 270, 360, false, false, false, true);

    // line: right edge, top end
    $this->addContent(sprintf("\n%.3F %.3F l ", $x1 + $w, $y1 + $h - $rTR));

    // curve: bottom-right corner
    $this->ellipse($x1 + $w - $rTR, $y1 + $h - $rTR, $rTR, 0, 0, 8, 0, 90, false, false, false, true);

    // line: bottom edge, right end
    $this->addContent(sprintf("\n%.3F %.3F l ", $x1 + $rTL, $y1 + $h));

    // curve: top-right corner
    $this->ellipse($x1 + $rTL, $y1 + $h - $rTL, $rTL, 0, 0, 8, 90, 180, false, false, false, true);

    // line: top edge, left end
    $this->addContent(sprintf("\n%.3F %.3F l ", $x1 + $rBL, $y1));

    // Close & clip
    $this->addContent(" W n");
  }

  /**
   * ends the last clipping shape
   */
  function clippingEnd() {
    $this->restore();
  }

  /**
   * scale
   * @param float $s_x scaling factor for width as percent
   * @param float $s_y scaling factor for height as percent
   * @param float $x Origin abscisse
   * @param float $y Origin ordinate
   */
  function scale($s_x, $s_y, $x, $y) {
    $y = $this->currentPageSize["height"] - $y;

    $tm = array(
      $s_x,        0,
      0,           $s_y,
      $x*(1-$s_x), $y*(1-$s_y)
    );

    $this->transform($tm);
  }

  /**
   * translate
   * @param float $t_x movement to the right
   * @param float $t_y movement to the bottom
   */
  function translate($t_x, $t_y) {
    $tm = array(
      1,    0,
      0,    1,
      $t_x, -$t_y
    );

    $this->transform($tm);
  }

  /**
   * rotate
   * @param float $angle angle in degrees for counter-clockwise rotation
   * @param float $x Origin abscisse
   * @param float $y Origin ordinate
   */
  function rotate($angle, $x, $y) {
    $y = $this->currentPageSize["height"] - $y;

    $a = deg2rad($angle);
    $cos_a = cos($a);
    $sin_a = sin($a);

    $tm = array(
      $cos_a,                     -$sin_a,
      $sin_a,                     $cos_a,
      $x - $sin_a*$y - $cos_a*$x, $y - $cos_a*$y + $sin_a*$x, 
    );

    $this->transform($tm);
  }

  /**
   * skew
   * @param float $angle_x
   * @param float $angle_y
   * @param float $x Origin abscisse
   * @param float $y Origin ordinate
   */
  function skew($angle_x, $angle_y, $x, $y) {
    $y = $this->currentPageSize["height"] - $y;

    $tan_x = tan(deg2rad($angle_x));
    $tan_y = tan(deg2rad($angle_y));

    $tm = array(
      1,         -$tan_y,
      -$tan_x,   1,
      $tan_x*$y, $tan_y*$x, 
    );

    $this->transform($tm);
  }

  /**
   * apply graphic transformations
   * @param array $tm transformation matrix
   */
  function transform($tm) {
    $this->addContent(vsprintf("\n %.3F %.3F %.3F %.3F %.3F %.3F cm", $tm));
  }

  /**
   * add a new page to the document
   * this also makes the new page the current active object
   */
  function newPage($insert = 0, $id = 0, $pos = 'after') {
    // if there is a state saved, then go up the stack closing them
    // then on the new page, re-open them with the right setings

    if ($this->nStateStack) {
      for ($i = $this->nStateStack; $i >= 1; $i--) {
        $this->restoreState($i);
      }
    }

    $this->numObj++;

    if ($insert) {
      // the id from the ezPdf class is the id of the contents of the page, not the page object itself
      // query that object to find the parent
      $rid = $this->objects[$id]['onPage'];
      $opt = array('rid' => $rid, 'pos' => $pos);
      $this->o_page($this->numObj, 'new', $opt);
    } else {
      $this->o_page($this->numObj, 'new');
    }

    // if there is a stack saved, then put that onto the page
    if ($this->nStateStack) {
      for ($i = 1; $i <= $this->nStateStack; $i++) {
        $this->saveState($i);
      }
    }

    // and if there has been a stroke or fill color set, then transfer them
    if (isset($this->currentColor)) {
      $this->setColor($this->currentColor, true);
    }

    if (isset($this->currentStrokeColor)) {
      $this->setStrokeColor($this->currentStrokeColor, true);
    }

    // if there is a line style set, then put this in too
    if (mb_strlen($this->currentLineStyle, '8bit')) {
      $this->addContent("\n$this->currentLineStyle");
    }

    // the call to the o_page object set currentContents to the present page, so this can be returned as the page id
    return $this->currentContents;
  }

  /**
   * output the pdf code, streaming it to the browser
   * the relevant headers are set so that hopefully the browser will recognise it
   */
  function stream($options = '') {
    // setting the options allows the adjustment of the headers
    // values at the moment are:
    // 'Content-Disposition' => 'filename'  - sets the filename, though not too sure how well this will
    //        work as in my trial the browser seems to use the filename of the php file with .pdf on the end
    // 'Accept-Ranges' => 1 or 0 - if this is not set to 1, then this header is not included, off by default
    //    this header seems to have caused some problems despite tha fact that it is supposed to solve
    //    them, so I am leaving it off by default.
    // 'compress' = > 1 or 0 - apply content stream compression, this is on (1) by default
    // 'Attachment' => 1 or 0 - if 1, force the browser to open a download dialog
    if (!is_array($options)) {
      $options = array();
    }

    if ( headers_sent()) {
      die("Unable to stream pdf: headers already sent");
    }

    $debug = empty($options['compression']);
    $tmp = ltrim($this->output($debug));

    header("Cache-Control: private");
    header("Content-type: application/pdf");

    //FIXME: I don't know that this is sufficient for determining content length (i.e. what about transport compression?)
    header("Content-Length: " . mb_strlen($tmp, '8bit'));
    $fileName = (isset($options['Content-Disposition']) ?  $options['Content-Disposition'] :  'file.pdf');

    if ( !isset($options["Attachment"]))
      $options["Attachment"] = true;

    $attachment = $options["Attachment"] ? "attachment" : "inline";
    
    // detect the character encoding of the incoming file
    $encoding = mb_detect_encoding($fileName);
    $fallbackfilename = mb_convert_encoding($fileName, "ISO-8859-1", $encoding); 
    $encodedfallbackfilename = rawurlencode($fallbackfilename);
    $encodedfilename = rawurlencode($fileName);

    header("Content-Disposition: $attachment; filename=". $encodedfallbackfilename ."; filename*=UTF-8''$encodedfilename");

    if (isset($options['Accept-Ranges']) && $options['Accept-Ranges'] == 1) {
      //FIXME: Is this the correct value ... spec says 1#range-unit
      header("Accept-Ranges: " . mb_strlen($tmp, '8bit'));
    }

    echo $tmp;
    flush();
  }

  /**
   * return the height in units of the current font in the given size
   */
  function getFontHeight($size) {
    if (!$this->numFonts) {
      $this->selectFont($this->defaultFont);
    }

    $font = $this->fonts[$this->currentFont];

    // for the current font, and the given size, what is the height of the font in user units
    if ( isset($font['Ascender']) && isset($font['Descender']) ) {
      $h = $font['Ascender']-$font['Descender'];
    }
    else {
      $h = $font['FontBBox'][3]-$font['FontBBox'][1];
    }

    // have to adjust by a font offset for Windows fonts.  unfortunately it looks like
    // the bounding box calculations are wrong and I don't know why.
    if (isset($font['FontHeightOffset'])) {
      // For CourierNew from Windows this needs to be -646 to match the
      // Adobe native Courier font.
      //
      // For FreeMono from GNU this needs to be -337 to match the
      // Courier font.
      //
      // Both have been added manually to the .afm and .ufm files.
      $h += (int)$font['FontHeightOffset'];
    }

    return $size*$h/1000;
  }

  function getFontXHeight($size) {
    if (!$this->numFonts) {
      $this->selectFont($this->defaultFont);
    }

    $font = $this->fonts[$this->currentFont];

    // for the current font, and the given size, what is the height of the font in user units
    if ( isset($font['XHeight']) ) {
      $xh = $font['Ascender']-$font['Descender'];
    }
    else {
      $xh = $this->getFontHeight($size) / 2;
    }

    return $size*$xh/1000;
  }

  /**
   * return the font descender, this will normally return a negative number
   * if you add this number to the baseline, you get the level of the bottom of the font
   * it is in the pdf user units
   */
  function getFontDescender($size) {
    // note that this will most likely return a negative value
    if (!$this->numFonts) {
      $this->selectFont($this->defaultFont);
    }

    //$h = $this->fonts[$this->currentFont]['FontBBox'][1];
    $h = $this->fonts[$this->currentFont]['Descender'];

    return $size*$h/1000;
  }

  /**
   * filter the text, this is applied to all text just before being inserted into the pdf document
   * it escapes the various things that need to be escaped, and so on
   *
   * @access private
   */
  function filterText($text, $bom = true, $convert_encoding = true) {
    if (!$this->numFonts) {
      $this->selectFont($this->defaultFont);
    }

    if ($convert_encoding) {
      $cf = $this->currentFont;
      if (isset($this->fonts[$cf]) && $this->fonts[$cf]['isUnicode']) {
        //$text = html_entity_decode($text, ENT_QUOTES, 'UTF-8');
        $text = $this->utf8toUtf16BE($text, $bom);
      } else {
        //$text = html_entity_decode($text, ENT_QUOTES);
        $text = mb_convert_encoding($text, self::$targetEncoding, 'UTF-8');
      }
    }

    // the chr(13) substitution fixes a bug seen in TCPDF (bug #1421290)
    return strtr($text, array(')' => '\\)', '(' => '\\(', '\\' => '\\\\', chr(13) => '\r'));
  }

  /**
   * return array containing codepoints (UTF-8 character values) for the
   * string passed in.
   *
   * based on the excellent TCPDF code by Nicola Asuni and the
   * RFC for UTF-8 at http://www.faqs.org/rfcs/rfc3629.html
   *
   * @access private
   * @author Orion Richardson
   * @since January 5, 2008
   * @param string $text UTF-8 string to process
   * @return array UTF-8 codepoints array for the string
   */
  function utf8toCodePointsArray(&$text) {
    $length = mb_strlen($text, '8bit'); // http://www.php.net/manual/en/function.mb-strlen.php#77040
    $unicode = array(); // array containing unicode values
    $bytes = array(); // array containing single character byte sequences
    $numbytes = 1; // number of octetc needed to represent the UTF-8 character

    for ($i = 0; $i < $length; $i++) {
      $c = ord($text[$i]); // get one string character at time
      if (count($bytes) === 0) { // get starting octect
        if ($c <= 0x7F) {
          $unicode[] = $c; // use the character "as is" because is ASCII
          $numbytes = 1;
        } elseif (($c >> 0x05) === 0x06) { // 2 bytes character (0x06 = 110 BIN)
          $bytes[] = ($c - 0xC0) << 0x06;
          $numbytes = 2;
        } elseif (($c >> 0x04) === 0x0E) { // 3 bytes character (0x0E = 1110 BIN)
          $bytes[] = ($c - 0xE0) << 0x0C;
          $numbytes = 3;
        } elseif (($c >> 0x03) === 0x1E) { // 4 bytes character (0x1E = 11110 BIN)
          $bytes[] = ($c - 0xF0) << 0x12;
          $numbytes = 4;
        } else {
          // use replacement character for other invalid sequences
          $unicode[] = 0xFFFD;
          $bytes = array();
          $numbytes = 1;
        }
      } elseif (($c >> 0x06) === 0x02) { // bytes 2, 3 and 4 must start with 0x02 = 10 BIN
        $bytes[] = $c - 0x80;
        if (count($bytes) === $numbytes) {
          // compose UTF-8 bytes to a single unicode value
          $c = $bytes[0];
          for ($j = 1; $j < $numbytes; $j++) {
            $c += ($bytes[$j] << (($numbytes - $j - 1) * 0x06));
          }
          if ((($c >= 0xD800) AND ($c <= 0xDFFF)) OR ($c >= 0x10FFFF)) {
            // The definition of UTF-8 prohibits encoding character numbers between
            // U+D800 and U+DFFF, which are reserved for use with the UTF-16
            // encoding form (as surrogate pairs) and do not directly represent
            // characters.
            $unicode[] = 0xFFFD; // use replacement character
          } else {
            $unicode[] = $c; // add char to array
          }
          // reset data for next char
          $bytes = array();
          $numbytes = 1;
        }
      } else {
        // use replacement character for other invalid sequences
        $unicode[] = 0xFFFD;
        $bytes = array();
        $numbytes = 1;
      }
    }
    return $unicode;
  }

  /**
   * convert UTF-8 to UTF-16 with an additional byte order marker
   * at the front if required.
   *
   * based on the excellent TCPDF code by Nicola Asuni and the
   * RFC for UTF-8 at http://www.faqs.org/rfcs/rfc3629.html
   *
   * @access private
   * @author Orion Richardson
   * @since January 5, 2008
   * @param string $text UTF-8 string to process
   * @param boolean $bom whether to add the byte order marker
   * @return string UTF-16 result string
   */
  function utf8toUtf16BE(&$text, $bom = true) {
    $cf = $this->currentFont;
    if (!$this->fonts[$cf]['isUnicode']) return $text;
    $out = $bom ? "\xFE\xFF" : '';

    $unicode = $this->utf8toCodePointsArray($text);
    foreach ($unicode as $c) {
      if ($c === 0xFFFD) {
        $out .= "\xFF\xFD"; // replacement character
      } elseif ($c < 0x10000) {
        $out .= chr($c >> 0x08) . chr($c & 0xFF);
       } else {
        $c -= 0x10000;
        $w1 = 0xD800 | ($c >> 0x10);
        $w2 = 0xDC00 | ($c & 0x3FF);
        $out .= chr($w1 >> 0x08) . chr($w1 & 0xFF) . chr($w2 >> 0x08) . chr($w2 & 0xFF);
      }
    }
    return $out;
  }

  /**
   * given a start position and information about how text is to be laid out, calculate where
   * on the page the text will end
   */
  private function getTextPosition($x, $y, $angle, $size, $wa, $text) {
    // given this information return an array containing x and y for the end position as elements 0 and 1
    $w = $this->getTextWidth($size, $text);

    // need to adjust for the number of spaces in this text
    $words = explode(' ', $text);
    $nspaces = count($words) -1;
    $w+= $wa*$nspaces;
    $a = deg2rad((float)$angle);

    return array(cos($a) *$w+$x, -sin($a) *$w+$y);
  }

  /**
   * Callback method used by smallCaps
   * 
   * @param array $matches
   * @return string
   */
  function toUpper($matches) {
    return mb_strtoupper($matches[0]);
  }

  function concatMatches($matches) {
    $str = "";
    foreach ($matches as $match){
      $str .= $match[0];
    }
    return $str;
  }

  /**
   * add text to the document, at a specified location, size and angle on the page
   */
  function registerText($font, $text) {
    if ( !$this->isUnicode || in_array(mb_strtolower(basename($font)), self::$coreFonts) ) {
      return;
    }

    if ( !isset($this->stringSubsets[$font]) ) {
      $this->stringSubsets[$font] = array();
    }

    $this->stringSubsets[$font] = array_unique(array_merge($this->stringSubsets[$font], $this->utf8toCodePointsArray($text)));
  }

  /**
   * add text to the document, at a specified location, size and angle on the page
   */
  function addText($x, $y, $size, $text, $angle = 0, $wordSpaceAdjust = 0, $charSpaceAdjust = 0, $smallCaps = false) {
    if (!$this->numFonts) {
      $this->selectFont($this->defaultFont);
    }

    $text = str_replace(array("\r", "\n"), "", $text);

    if ( $smallCaps ) {
      preg_match_all("/(\P{Ll}+)/u", $text, $matches, PREG_SET_ORDER);
      $lower = $this->concatMatches($matches);
      d($lower);

      preg_match_all("/(\p{Ll}+)/u", $text, $matches, PREG_SET_ORDER);
      $other = $this->concatMatches($matches);
      d($other);

      //$text = preg_replace_callback("/\p{Ll}/u", array($this, "toUpper"), $text);
    }

    // if there are any open callbacks, then they should be called, to show the start of the line
    if ($this->nCallback > 0) {
      for ($i = $this->nCallback; $i > 0; $i--) {
        // call each function
        $info = array(
          'x' => $x,
          'y' => $y,
          'angle' => $angle,
          'status' => 'sol',
          'p'         => $this->callback[$i]['p'],
          'nCallback' => $this->callback[$i]['nCallback'],
          'height'    => $this->callback[$i]['height'],
          'descender' => $this->callback[$i]['descender']
        );

        $func = $this->callback[$i]['f'];
        $this->$func($info);
      }
    }

    if ($angle == 0) {
      $this->addContent(sprintf("\nBT %.3F %.3F Td", $x, $y));
    } else {
      $a = deg2rad((float)$angle);
      $this->addContent(sprintf("\nBT %.3F %.3F %.3F %.3F %.3F %.3F Tm", cos($a), -sin($a), sin($a), cos($a), $x, $y));
    }

    if ($wordSpaceAdjust != 0 || $wordSpaceAdjust != $this->wordSpaceAdjust) {
      $this->wordSpaceAdjust = $wordSpaceAdjust;
      $this->addContent(sprintf(" %.3F Tw", $wordSpaceAdjust));
    }

    if ($charSpaceAdjust != 0 || $charSpaceAdjust != $this->charSpaceAdjust) {
      $this->charSpaceAdjust = $charSpaceAdjust;
      $this->addContent(sprintf(" %.3F Tc", $charSpaceAdjust));
    }

    $len = mb_strlen($text);
    $start = 0;

    if ($start < $len) {
      $part = $text; // OAR - Don't need this anymore, given that $start always equals zero.  substr($text, $start);
      $place_text = $this->filterText($part, false);
      // modify unicode text so that extra word spacing is manually implemented (bug #)
      $cf = $this->currentFont;
      if ($this->fonts[$cf]['isUnicode'] && $wordSpaceAdjust != 0) {
        $space_scale = 1000 / $size;
        //$place_text = str_replace(' ', ') ( ) '.($this->getTextWidth($size, chr(32), $wordSpaceAdjust)*-75).' (', $place_text);
        $place_text = str_replace(' ', ' ) '.(-round($space_scale*$wordSpaceAdjust)).' (', $place_text);
      }
      $this->addContent(" /F$this->currentFontNum ".sprintf('%.1F Tf ', $size));
      $this->addContent(" [($place_text)] TJ");
    }

    $this->addContent(' ET');

    // if there are any open callbacks, then they should be called, to show the end of the line
    if ($this->nCallback > 0) {
      for ($i = $this->nCallback; $i > 0; $i--) {
        // call each function
        $tmp = $this->getTextPosition($x, $y, $angle, $size, $wordSpaceAdjust, $text);
        $info = array(
          'x' => $tmp[0],
          'y' => $tmp[1],
          'angle' => $angle,
          'status' => 'eol',
          'p'         => $this->callback[$i]['p'],
          'nCallback' => $this->callback[$i]['nCallback'],
          'height'    => $this->callback[$i]['height'],
          'descender' => $this->callback[$i]['descender']
        );
        $func = $this->callback[$i]['f'];
        $this->$func($info);
      }
    }
  }

  /**
   * calculate how wide a given text string will be on a page, at a given size.
   * this can be called externally, but is also used by the other class functions
   */
  function getTextWidth($size, $text, $word_spacing = 0, $char_spacing = 0) {
    static $ord_cache = array();

    // this function should not change any of the settings, though it will need to
    // track any directives which change during calculation, so copy them at the start
    // and put them back at the end.
    $store_currentTextState = $this->currentTextState;

    if (!$this->numFonts) {
      $this->selectFont($this->defaultFont);
    }

    $text = str_replace(array("\r", "\n"), "", $text);

    // converts a number or a float to a string so it can get the width
    $text = "$text";

    // hmm, this is where it all starts to get tricky - use the font information to
    // calculate the width of each character, add them up and convert to user units
    $w = 0;
    $cf = $this->currentFont;
    $current_font = $this->fonts[$cf];
    $space_scale = 1000 / ( $size > 0 ? $size : 1 );
    $n_spaces = 0;

    if ( $current_font['isUnicode']) {
      // for Unicode, use the code points array to calculate width rather
      // than just the string itself
      $unicode = $this->utf8toCodePointsArray($text);

      foreach ($unicode as $char) {
        // check if we have to replace character
        if ( isset($current_font['differences'][$char])) {
          $char = $current_font['differences'][$char];
        }

        if ( isset($current_font['C'][$char]) ) {
          $char_width = $current_font['C'][$char];

          // add the character width
          $w += $char_width;

          // add additional padding for space
          if ( isset($current_font['codeToName'][$char]) && $current_font['codeToName'][$char] === 'space' ) {  // Space
            $w += $word_spacing * $space_scale;
            $n_spaces++;
          }
        }
      }

      // add additionnal char spacing
      if ( $char_spacing != 0 ) {
        $w += $char_spacing * $space_scale * (count($unicode) + $n_spaces);
      }

    } else {
      // If CPDF is in Unicode mode but the current font does not support Unicode we need to convert the character set to Windows-1252
      if ( $this->isUnicode ) { 
        $text = mb_convert_encoding($text, 'Windows-1252', 'UTF-8');
      }

      $len = mb_strlen($text, 'Windows-1252');

      for ($i = 0; $i < $len; $i++) {
        $c = $text[$i];
        $char = isset($ord_cache[$c]) ? $ord_cache[$c] : ($ord_cache[$c] = ord($c));

        // check if we have to replace character
        if ( isset($current_font['differences'][$char])) {
          $char = $current_font['differences'][$char];
        }

        if ( isset($current_font['C'][$char]) ) {
          $char_width = $current_font['C'][$char];

          // add the character width
          $w += $char_width;

          // add additional padding for space
          if ( isset($current_font['codeToName'][$char]) && $current_font['codeToName'][$char] === 'space' ) {  // Space
            $w += $word_spacing * $space_scale;
            $n_spaces++;
          }
        }
      }

      // add additionnal char spacing
      if ( $char_spacing != 0 )  {
        $w += $char_spacing * $space_scale * ($len + $n_spaces);
      }
    }

    $this->currentTextState = $store_currentTextState;
    $this->setCurrentFont();

    return $w*$size/1000;
  }

  /**
   * this will be called at a new page to return the state to what it was on the
   * end of the previous page, before the stack was closed down
   * This is to get around not being able to have open 'q' across pages
   *
   */
  function saveState($pageEnd = 0) {
    if ($pageEnd) {
      // this will be called at a new page to return the state to what it was on the
      // end of the previous page, before the stack was closed down
      // This is to get around not being able to have open 'q' across pages
      $opt = $this->stateStack[$pageEnd];
      // ok to use this as stack starts numbering at 1
      $this->setColor($opt['col'], true);
      $this->setStrokeColor($opt['str'], true);
      $this->addContent("\n".$opt['lin']);
      //    $this->currentLineStyle = $opt['lin'];
    } else {
      $this->nStateStack++;
      $this->stateStack[$this->nStateStack] = array(
        'col' => $this->currentColor,
        'str' => $this->currentStrokeColor,
        'lin' => $this->currentLineStyle
      );
    }

    $this->save();
  }

  /**
   * restore a previously saved state
   */
  function restoreState($pageEnd = 0) {
    if (!$pageEnd) {
      $n = $this->nStateStack;
      $this->currentColor =       $this->stateStack[$n]['col'];
      $this->currentStrokeColor = $this->stateStack[$n]['str'];
      $this->addContent("\n".$this->stateStack[$n]['lin']);
      $this->currentLineStyle =    $this->stateStack[$n]['lin'];
      $this->stateStack[$n] = null;
      unset($this->stateStack[$n]);
      $this->nStateStack--;
    }

    $this->restore();
  }

  /**
   * make a loose object, the output will go into this object, until it is closed, then will revert to
   * the current one.
   * this object will not appear until it is included within a page.
   * the function will return the object number
   */
  function openObject() {
    $this->nStack++;
    $this->stack[$this->nStack] = array('c' => $this->currentContents, 'p' => $this->currentPage);
    // add a new object of the content type, to hold the data flow
    $this->numObj++;
    $this->o_contents($this->numObj, 'new');
    $this->currentContents = $this->numObj;
    $this->looseObjects[$this->numObj] = 1;

    return $this->numObj;
  }

  /**
   * open an existing object for editing
   */
  function reopenObject($id) {
    $this->nStack++;
    $this->stack[$this->nStack] = array('c' => $this->currentContents, 'p' => $this->currentPage);
    $this->currentContents = $id;

    // also if this object is the primary contents for a page, then set the current page to its parent
    if (isset($this->objects[$id]['onPage'])) {
      $this->currentPage = $this->objects[$id]['onPage'];
    }
  }

  /**
   * close an object
   */
  function closeObject() {
    // close the object, as long as there was one open in the first place, which will be indicated by
    // an objectId on the stack.
    if ($this->nStack > 0) {
      $this->currentContents = $this->stack[$this->nStack]['c'];
      $this->currentPage = $this->stack[$this->nStack]['p'];
      $this->nStack--;
      // easier to probably not worry about removing the old entries, they will be overwritten
      // if there are new ones.
    }
  }

  /**
   * stop an object from appearing on pages from this point on
   */
  function stopObject($id) {
    // if an object has been appearing on pages up to now, then stop it, this page will
    // be the last one that could contian it.
    if (isset($this->addLooseObjects[$id])) {
      $this->addLooseObjects[$id] = '';
    }
  }

  /**
   * after an object has been created, it wil only show if it has been added, using this function.
   */
  function addObject($id, $options = 'add') {
    // add the specified object to the page
    if (isset($this->looseObjects[$id]) && $this->currentContents != $id) {
      // then it is a valid object, and it is not being added to itself
      switch ($options) {
      case 'all':
        // then this object is to be added to this page (done in the next block) and
        // all future new pages.
        $this->addLooseObjects[$id] = 'all';

      case 'add':
        if (isset($this->objects[$this->currentContents]['onPage'])) {
          // then the destination contents is the primary for the page
          // (though this object is actually added to that page)
          $this->o_page($this->objects[$this->currentContents]['onPage'], 'content', $id);
        }
        break;

      case 'even':
        $this->addLooseObjects[$id] = 'even';
        $pageObjectId = $this->objects[$this->currentContents]['onPage'];
        if ($this->objects[$pageObjectId]['info']['pageNum']%2 == 0) {
          $this->addObject($id);
          // hacky huh :)
        }
        break;

      case 'odd':
        $this->addLooseObjects[$id] = 'odd';
        $pageObjectId = $this->objects[$this->currentContents]['onPage'];
        if ($this->objects[$pageObjectId]['info']['pageNum']%2 == 1) {
          $this->addObject($id);
          // hacky huh :)
        }
        break;

      case 'next':
        $this->addLooseObjects[$id] = 'all';
        break;

      case 'nexteven':
        $this->addLooseObjects[$id] = 'even';
        break;

      case 'nextodd':
        $this->addLooseObjects[$id] = 'odd';
        break;
      }
    }
  }

  /**
   * return a storable representation of a specific object
   */
  function serializeObject($id) {
    if ( array_key_exists($id, $this->objects)) {
      return serialize($this->objects[$id]);
    }
  }

  /**
   * restore an object from its stored representation.  returns its new object id.
   */
  function restoreSerializedObject($obj) {
    $obj_id = $this->openObject();
    $this->objects[$obj_id] = unserialize($obj);
    $this->closeObject();
    return $obj_id;
  }

  /**
   * add content to the documents info object
   */
  function addInfo($label, $value = 0) {
    // this will only work if the label is one of the valid ones.
    // modify this so that arrays can be passed as well.
    // if $label is an array then assume that it is key => value pairs
    // else assume that they are both scalar, anything else will probably error
    if (is_array($label)) {
      foreach ($label as $l => $v) {
        $this->o_info($this->infoObject, $l, $v);
      }
    } else {
      $this->o_info($this->infoObject, $label, $value);
    }
  }

  /**
   * set the viewer preferences of the document, it is up to the browser to obey these.
   */
  function setPreferences($label, $value = 0) {
    // this will only work if the label is one of the valid ones.
    if (is_array($label)) {
      foreach ($label as $l => $v) {
        $this->o_catalog($this->catalogId, 'viewerPreferences', array($l => $v));
      }
    } else {
      $this->o_catalog($this->catalogId, 'viewerPreferences', array($label => $value));
    }
  }

  /**
   * extract an integer from a position in a byte stream
   */
  private function getBytes(&$data, $pos, $num) {
    // return the integer represented by $num bytes from $pos within $data
    $ret = 0;
    for ($i = 0; $i < $num; $i++) {
      $ret *= 256;
      $ret += ord($data[$pos+$i]);
    }

    return $ret;
  }

  /**
   * Check if image already added to pdf image directory.
   * If yes, need not to create again (pass empty data)
   */
  function image_iscached($imgname) {
    return isset($this->imagelist[$imgname]);
  }

  /**
   * add a PNG image into the document, from a GD object
   * this should work with remote files
   *
   * @param string   $file    The PNG file
   * @param float    $x       X position
   * @param float    $y       Y position
   * @param float    $w       Width
   * @param float    $h       Height
   * @param resource $img     A GD resource
   * @param bool     $is_mask true if the image is a mask
   * @param bool     $mask    true if the image is masked
   */
  function addImagePng($file, $x, $y, $w = 0.0, $h = 0.0, &$img, $is_mask = false, $mask = null) {
    if (!function_exists("imagepng")) {
      throw new Exception("The PHP GD extension is required, but is not installed.");
    }

    //if already cached, need not to read again
    if ( isset($this->imagelist[$file]) ) {
      $data = null;
    }
    else {
      // Example for transparency handling on new image. Retain for current image
      // $tIndex = imagecolortransparent($img);
      // if ($tIndex > 0) {
      //   $tColor    = imagecolorsforindex($img, $tIndex);
      //   $new_tIndex    = imagecolorallocate($new_img, $tColor['red'], $tColor['green'], $tColor['blue']);
      //   imagefill($new_img, 0, 0, $new_tIndex);
      //   imagecolortransparent($new_img, $new_tIndex);
      // }
      // blending mode (literal/blending) on drawing into current image. not relevant when not saved or not drawn
      //imagealphablending($img, true);

      //default, but explicitely set to ensure pdf compatibility
      imagesavealpha($img, false/*!$is_mask && !$mask*/);

      $error = 0;
      //DEBUG_IMG_TEMP
      //debugpng
      if (DEBUGPNG) print '[addImagePng '.$file.']';

      ob_start();
      @imagepng($img);
      $data = ob_get_clean();

      if ($data == '') {
        $error = 1;
        $errormsg = 'trouble writing file from GD';
        //DEBUG_IMG_TEMP
        //debugpng
        if (DEBUGPNG) print 'trouble writing file from GD';
      }

      if ($error) {
        $this->addMessage('PNG error - ('.$file.') '.$errormsg);
        return;
      }
    }  //End isset($this->imagelist[$file]) (png Duplicate removal)

    $this->addPngFromBuf($file, $x, $y, $w, $h, $data, $is_mask, $mask);
  }

  protected function addImagePngAlpha($file, $x, $y, $w, $h, $byte) {
    // generate images
    $img = imagecreatefrompng($file);

    if ($img === false) {
      return;
    }

    // FIXME The pixel transformation doesn't work well with 8bit PNGs
    $eight_bit = ($byte & 4) !== 4;

    $wpx = imagesx($img);
    $hpx = imagesy($img);

    imagesavealpha($img, false);

    // create temp alpha file
    $tempfile_alpha = tempnam($this->tmp, "cpdf_img_");
    @unlink($tempfile_alpha);
    $tempfile_alpha = "$tempfile_alpha.png";

    // create temp plain file
    $tempfile_plain = tempnam($this->tmp, "cpdf_img_");
    @unlink($tempfile_plain);
    $tempfile_plain = "$tempfile_plain.png";

    $imgalpha = imagecreate($wpx, $hpx);
    imagesavealpha($imgalpha, false);

    // generate gray scale palette (0 -> 255)
    for ($c = 0; $c < 256; ++$c) {
      imagecolorallocate($imgalpha, $c, $c, $c);
    }

    // Use PECL gmagick + Graphics Magic to process transparent PNG images
    if (extension_loaded("gmagick")) {
      $gmagick = new Gmagick($file);
      $gmagick->setimageformat('png');

      // Get opacity channel (negative of alpha channel)
      $alpha_channel_neg = clone $gmagick;
      $alpha_channel_neg->separateimagechannel(Gmagick::CHANNEL_OPACITY);

      // Negate opacity channel
      $alpha_channel = new Gmagick();
      $alpha_channel->newimage($wpx, $hpx, "#FFFFFF", "png");
      $alpha_channel->compositeimage($alpha_channel_neg, Gmagick::COMPOSITE_DIFFERENCE, 0, 0);
      $alpha_channel->separateimagechannel(Gmagick::CHANNEL_RED);
      $alpha_channel->writeimage($tempfile_alpha);

      // Cast to 8bit+palette
      $imgalpha_ = imagecreatefrompng($tempfile_alpha);
      imagecopy($imgalpha, $imgalpha_, 0, 0, 0, 0, $wpx, $hpx);
      imagedestroy($imgalpha_);
      imagepng($imgalpha, $tempfile_alpha);

      // Make opaque image
      $color_channels = new Gmagick();
      $color_channels->newimage($wpx, $hpx, "#FFFFFF", "png");
      $color_channels->compositeimage($gmagick, Gmagick::COMPOSITE_COPYRED, 0, 0);
      $color_channels->compositeimage($gmagick, Gmagick::COMPOSITE_COPYGREEN, 0, 0);
      $color_channels->compositeimage($gmagick, Gmagick::COMPOSITE_COPYBLUE, 0, 0);
      $color_channels->writeimage($tempfile_plain);

      $imgplain = imagecreatefrompng($tempfile_plain);
    }

    // Use PECL imagick + ImageMagic to process transparent PNG images
    elseif (extension_loaded("imagick")) {
      // Native cloning was added to pecl-imagick in svn commit 263814
      // the first version containing it was 3.0.1RC1
      static $imagickClonable = null;
      if($imagickClonable === null) {
        $imagickClonable = version_compare(phpversion('imagick'), '3.0.1rc1') > 0;
      }

      $imagick = new Imagick($file);
      $imagick->setFormat('png');

      // Get opacity channel (negative of alpha channel)
      $alpha_channel = $imagickClonable ? clone $imagick : $imagick->clone();
      $alpha_channel->separateImageChannel(Imagick::CHANNEL_ALPHA);
      $alpha_channel->negateImage(true);
      $alpha_channel->writeImage($tempfile_alpha);

      // Cast to 8bit+palette
      $imgalpha_ = imagecreatefrompng($tempfile_alpha);
      imagecopy($imgalpha, $imgalpha_, 0, 0, 0, 0, $wpx, $hpx);
      imagedestroy($imgalpha_);
      imagepng($imgalpha, $tempfile_alpha);

      // Make opaque image
      $color_channels = new Imagick();
      $color_channels->newImage($wpx, $hpx, "#FFFFFF", "png");
      $color_channels->compositeImage($imagick, Imagick::COMPOSITE_COPYRED, 0, 0);
      $color_channels->compositeImage($imagick, Imagick::COMPOSITE_COPYGREEN, 0, 0);
      $color_channels->compositeImage($imagick, Imagick::COMPOSITE_COPYBLUE, 0, 0);
      $color_channels->writeImage($tempfile_plain);

      $imgplain = imagecreatefrompng($tempfile_plain);
    }
    else {
      // allocated colors cache
      $allocated_colors = array();

      // extract alpha channel
      for ($xpx = 0; $xpx < $wpx; ++$xpx) {
        for ($ypx = 0; $ypx < $hpx; ++$ypx) {
          $color = imagecolorat($img, $xpx, $ypx);
          $col = imagecolorsforindex($img, $color);
          $alpha = $col['alpha'];

          if ($eight_bit) {
            // with gamma correction
            $gammacorr = 2.2;
            $pixel = pow((((127 - $alpha) * 255 / 127) / 255), $gammacorr) * 255;
          }

          else {
            // without gamma correction
            $pixel = (127 - $alpha) * 2;

            $key = $col['red'].$col['green'].$col['blue'];

            if (!isset($allocated_colors[$key])) {
              $pixel_img = imagecolorallocate($img, $col['red'], $col['green'], $col['blue']);
              $allocated_colors[$key] = $pixel_img;
            }
            else {
              $pixel_img = $allocated_colors[$key]; 
            }

            imagesetpixel($img, $xpx, $ypx, $pixel_img);
          }

          imagesetpixel($imgalpha, $xpx, $ypx, $pixel);
        }
      }

      // extract image without alpha channel
      $imgplain = imagecreatetruecolor($wpx, $hpx);
      imagecopy($imgplain, $img, 0, 0, 0, 0, $wpx, $hpx);
      imagedestroy($img);

      imagepng($imgalpha, $tempfile_alpha);
      imagepng($imgplain, $tempfile_plain);
    }

    // embed mask image
    $this->addImagePng($tempfile_alpha, $x, $y, $w, $h, $imgalpha, true);
    imagedestroy($imgalpha);

    // embed image, masked with previously embedded mask
    $this->addImagePng($tempfile_plain, $x, $y, $w, $h, $imgplain, false, true);
    imagedestroy($imgplain);

    // remove temp files
    unlink($tempfile_alpha);
    unlink($tempfile_plain);
  }

  /**
   * add a PNG image into the document, from a file
   * this should work with remote files
   */
  function addPngFromFile($file, $x, $y, $w = 0, $h = 0) {
    if (!function_exists("imagecreatefrompng")) {
      throw new Exception("The PHP GD extension is required, but is not installed.");
    }

    //if already cached, need not to read again
    if ( isset($this->imagelist[$file]) ) {
      $img = null;
    } 

    else {
      $info = file_get_contents ($file, false, null, 24, 5);
      $meta = unpack("CbitDepth/CcolorType/CcompressionMethod/CfilterMethod/CinterlaceMethod", $info);
      $bit_depth = $meta["bitDepth"];
      $color_type = $meta["colorType"];

      // http://www.w3.org/TR/PNG/#11IHDR
      // 3 => indexed
      // 4 => greyscale with alpha
      // 6 => fullcolor with alpha
      $is_alpha = in_array($color_type, array(4, 6)) || ($color_type == 3 && $bit_depth != 4);

      if ($is_alpha) { // exclude grayscale alpha
        return $this->addImagePngAlpha($file, $x, $y, $w, $h, $color_type);
      }

      //png files typically contain an alpha channel.
      //pdf file format or class.pdf does not support alpha blending.
      //on alpha blended images, more transparent areas have a color near black.
      //This appears in the result on not storing the alpha channel.
      //Correct would be the box background image or its parent when transparent.
      //But this would make the image dependent on the background.
      //Therefore create an image with white background and copy in
      //A more natural background than black is white.
      //Therefore create an empty image with white background and merge the
      //image in with alpha blending.
      $imgtmp = @imagecreatefrompng($file);
      if (!$imgtmp) {
        return;
      }
      $sx = imagesx($imgtmp);
      $sy = imagesy($imgtmp);
      $img = imagecreatetruecolor($sx,$sy);
      imagealphablending($img, true);

      // @todo is it still needed ??
      $ti = imagecolortransparent($imgtmp);
      if ($ti >= 0) {
        $tc = imagecolorsforindex($imgtmp,$ti);
        $ti = imagecolorallocate($img,$tc['red'],$tc['green'],$tc['blue']);
        imagefill($img,0,0,$ti);
        imagecolortransparent($img, $ti);
      } else {
        imagefill($img,1,1,imagecolorallocate($img,255,255,255));
      }

      imagecopy($img,$imgtmp,0,0,0,0,$sx,$sy);
      imagedestroy($imgtmp);
    }
    $this->addImagePng($file, $x, $y, $w, $h, $img);

    if ( $img ) {
      imagedestroy($img);
    }
  }

  /**
   * add a PNG image into the document, from a memory buffer of the file
   */
  function addPngFromBuf($file, $x, $y, $w = 0.0, $h = 0.0, &$data, $is_mask = false, $mask = null) {
    if ( isset($this->imagelist[$file]) ) {
      $data = null;
      $info['width'] = $this->imagelist[$file]['w'];
      $info['height'] = $this->imagelist[$file]['h'];
      $label = $this->imagelist[$file]['label'];
    }

    else {
      if ($data == null) {
        $this->addMessage('addPngFromBuf error - data not present!');
        return;
      }

      $error = 0;

      if (!$error) {
        $header = chr(137) .chr(80) .chr(78) .chr(71) .chr(13) .chr(10) .chr(26) .chr(10);

        if (mb_substr($data, 0, 8, '8bit') != $header) {
          $error = 1;

          if (DEBUGPNG) print '[addPngFromFile this file does not have a valid header '.$file.']';

          $errormsg = 'this file does not have a valid header';
        }
      }

      if (!$error) {
        // set pointer
        $p = 8;
        $len = mb_strlen($data, '8bit');

        // cycle through the file, identifying chunks
        $haveHeader = 0;
        $info = array();
        $idata = '';
        $pdata = '';

        while ($p < $len) {
          $chunkLen = $this->getBytes($data, $p, 4);
          $chunkType = mb_substr($data, $p+4, 4, '8bit');

          switch ($chunkType) {
          case 'IHDR':
            // this is where all the file information comes from
            $info['width'] = $this->getBytes($data, $p+8, 4);
            $info['height'] = $this->getBytes($data, $p+12, 4);
            $info['bitDepth'] = ord($data[$p+16]);
            $info['colorType'] = ord($data[$p+17]);
            $info['compressionMethod'] = ord($data[$p+18]);
            $info['filterMethod'] = ord($data[$p+19]);
            $info['interlaceMethod'] = ord($data[$p+20]);

            //print_r($info);
            $haveHeader = 1;
            if ($info['compressionMethod'] != 0) {
              $error = 1;

              //debugpng
              if (DEBUGPNG) print '[addPngFromFile unsupported compression method '.$file.']';

              $errormsg = 'unsupported compression method';
            }

            if ($info['filterMethod'] != 0) {
              $error = 1;

              //debugpng
              if (DEBUGPNG) print '[addPngFromFile unsupported filter method '.$file.']';

              $errormsg = 'unsupported filter method';
            }
            break;

          case 'PLTE':
            $pdata.= mb_substr($data, $p+8, $chunkLen, '8bit');
            break;

          case 'IDAT':
            $idata.= mb_substr($data, $p+8, $chunkLen, '8bit');
            break;

          case 'tRNS':
            //this chunk can only occur once and it must occur after the PLTE chunk and before IDAT chunk
            //print "tRNS found, color type = ".$info['colorType']."\n";
            $transparency = array();

            switch ($info['colorType']) {
              // indexed color, rbg
              case 3:
                /* corresponding to entries in the plte chunk
                 Alpha for palette index 0: 1 byte
                 Alpha for palette index 1: 1 byte
                 ...etc...
                */
                // there will be one entry for each palette entry. up until the last non-opaque entry.
                // set up an array, stretching over all palette entries which will be o (opaque) or 1 (transparent)
                $transparency['type'] = 'indexed';
                $trans = 0;

                for ($i = $chunkLen; $i >= 0; $i--) {
                  if (ord($data[$p+8+$i]) == 0) {
                    $trans = $i;
                  }
                }

                $transparency['data'] = $trans;
              break;

              // grayscale
              case 0:
                /* corresponding to entries in the plte chunk
                 Gray: 2 bytes, range 0 .. (2^bitdepth)-1
                */
                //            $transparency['grayscale'] = $this->PRVT_getBytes($data,$p+8,2); // g = grayscale
                $transparency['type'] = 'indexed';
                $transparency['data'] = ord($data[$p+8+1]);
              break;

              // truecolor
              case 2:      
                /* corresponding to entries in the plte chunk
                 Red: 2 bytes, range 0 .. (2^bitdepth)-1
                 Green: 2 bytes, range 0 .. (2^bitdepth)-1
                 Blue: 2 bytes, range 0 .. (2^bitdepth)-1
                */
                $transparency['r'] = $this->getBytes($data, $p+8, 2);
                // r from truecolor
                $transparency['g'] = $this->getBytes($data, $p+10, 2);
                // g from truecolor
                $transparency['b'] = $this->getBytes($data, $p+12, 2);
                // b from truecolor

                $transparency['type'] = 'color-key';
              break;

              //unsupported transparency type
              default:
                if (DEBUGPNG) print '[addPngFromFile unsupported transparency type '.$file.']';
                break;
            }

            // KS End new code
            break;

          default:
            break;
          }

          $p += $chunkLen+12;
        }

        if (!$haveHeader) {
          $error = 1;

          //debugpng
          if (DEBUGPNG) print '[addPngFromFile information header is missing '.$file.']';

          $errormsg = 'information header is missing';
        }

        if (isset($info['interlaceMethod']) && $info['interlaceMethod']) {
          $error = 1;

          //debugpng
          if (DEBUGPNG) print '[addPngFromFile no support for interlaced images in pdf '.$file.']';

          $errormsg = 'There appears to be no support for interlaced images in pdf.';
        }
      }

      if (!$error && $info['bitDepth'] > 8) {
        $error = 1;

        //debugpng
        if (DEBUGPNG) print '[addPngFromFile bit depth of 8 or less is supported '.$file.']';

        $errormsg = 'only bit depth of 8 or less is supported';
      }
  
      if (!$error) {
        switch ($info['colorType']) {
        case 3:
          $color = 'DeviceRGB';
          $ncolor = 1;
          break;

        case 2:
          $color = 'DeviceRGB';
          $ncolor = 3;
          break;

        case 0:
          $color = 'DeviceGray';
          $ncolor = 1;
          break;

        default: 
          $error = 1;

          //debugpng
          if (DEBUGPNG) print '[addPngFromFile alpha channel not supported: '.$info['colorType'].' '.$file.']';

          $errormsg = 'transparancey alpha channel not supported, transparency only supported for palette images.';
        }
      }

      if ($error) {
        $this->addMessage('PNG error - ('.$file.') '.$errormsg);
        return;
      }

      //print_r($info);
      // so this image is ok... add it in.
      $this->numImages++;
      $im = $this->numImages;
      $label = "I$im";
      $this->numObj++;

      //  $this->o_image($this->numObj,'new',array('label' => $label,'data' => $idata,'iw' => $w,'ih' => $h,'type' => 'png','ic' => $info['width']));
      $options = array(
        'label' => $label,
        'data' => $idata,
        'bitsPerComponent' => $info['bitDepth'],
        'pdata' => $pdata,
        'iw' => $info['width'],
        'ih' => $info['height'],
        'type' => 'png',
        'color' => $color,
        'ncolor' => $ncolor,
        'masked' => $mask,
        'isMask' => $is_mask
      );

      if (isset($transparency)) {
        $options['transparency'] = $transparency;
      }

      $this->o_image($this->numObj, 'new', $options);
      $this->imagelist[$file] = array('label' =>$label, 'w' => $info['width'], 'h' => $info['height']);
    }

    if ($is_mask) {
      return;
    }

    if ($w <= 0 && $h <= 0) {
      $w = $info['width'];
      $h = $info['height'];
    }

    if ($w <= 0) {
      $w = $h/$info['height']*$info['width'];
    }

    if ($h <= 0) {
      $h = $w*$info['height']/$info['width'];
    }

    $this->addContent(sprintf("\nq\n%.3F 0 0 %.3F %.3F %.3F cm /%s Do\nQ", $w, $h, $x, $y, $label));
  }

  /**
   * add a JPEG image into the document, from a file
   */
  function addJpegFromFile($img, $x, $y, $w = 0, $h = 0) {
    // attempt to add a jpeg image straight from a file, using no GD commands
    // note that this function is unable to operate on a remote file.

    if (!file_exists($img)) {
      return;
    }

    if ( $this->image_iscached($img) ) {
      $data = null;
      $imageWidth  = $this->imagelist[$img]['w'];
      $imageHeight = $this->imagelist[$img]['h'];
      $channels    = $this->imagelist[$img]['c'];
    } 
    else {
      $tmp = getimagesize($img);
      $imageWidth  = $tmp[0];
      $imageHeight = $tmp[1];

      if ( isset($tmp['channels']) ) {
        $channels = $tmp['channels'];
      } else {
        $channels = 3;
      }

      $data = file_get_contents($img);
    }

    if ($w <= 0 && $h <= 0) {
      $w = $imageWidth;
    }

    if ($w == 0) {
      $w = $h/$imageHeight*$imageWidth;
    }

    if ($h == 0) {
      $h = $w*$imageHeight/$imageWidth;
    }

    $this->addJpegImage_common($data, $x, $y, $w, $h, $imageWidth, $imageHeight, $channels, $img);
  }

  /**
   * common code used by the two JPEG adding functions
   */
  private function addJpegImage_common(&$data, $x, $y, $w = 0, $h = 0, $imageWidth, $imageHeight, $channels = 3, $imgname) {
    if ( $this->image_iscached($imgname) ) {
      $label = $this->imagelist[$imgname]['label'];
      //debugpng
      //if (DEBUGPNG) print '[addJpegImage_common Duplicate '.$imgname.']';

    } else {
      if ($data == null) {
        $this->addMessage('addJpegImage_common error - ('.$imgname.') data not present!');
        return;
      }

      // note that this function is not to be called externally
      // it is just the common code between the GD and the file options
      $this->numImages++;
      $im = $this->numImages;
      $label = "I$im";
      $this->numObj++;

      $this->o_image($this->numObj, 'new', array(
        'label' => $label, 
        'data' => &$data, 
        'iw' => $imageWidth, 
        'ih' => $imageHeight, 
        'channels' => $channels
      ));

      $this->imagelist[$imgname] = array('label' =>$label, 'w' => $imageWidth, 'h' => $imageHeight, 'c'=> $channels);
    }

    $this->addContent(sprintf("\nq\n%.3F 0 0 %.3F %.3F %.3F cm /%s Do\nQ ", $w, $h, $x, $y, $label));
  }

  /**
   * specify where the document should open when it first starts
   */
  function openHere($style, $a = 0, $b = 0, $c = 0) {
    // this function will open the document at a specified page, in a specified style
    // the values for style, and the required paramters are:
    // 'XYZ'  left, top, zoom
    // 'Fit'
    // 'FitH' top
    // 'FitV' left
    // 'FitR' left,bottom,right
    // 'FitB'
    // 'FitBH' top
    // 'FitBV' left
    $this->numObj++;
    $this->o_destination($this->numObj, 'new', array('page' => $this->currentPage, 'type' => $style, 'p1' => $a, 'p2' => $b, 'p3' => $c));
    $id = $this->catalogId;
    $this->o_catalog($id, 'openHere', $this->numObj);
  }

  /**
   * Add JavaScript code to the PDF document
   * 
   * @param string $code
   * @return void
   */
  function addJavascript($code) {
    $this->javascript .= $code;
  }

  /**
   * create a labelled destination within the document
   */
  function addDestination($label, $style, $a = 0, $b = 0, $c = 0) {
    // associates the given label with the destination, it is done this way so that a destination can be specified after
    // it has been linked to
    // styles are the same as the 'openHere' function
    $this->numObj++;
    $this->o_destination($this->numObj, 'new', array('page' => $this->currentPage, 'type' => $style, 'p1' => $a, 'p2' => $b, 'p3' => $c));
    $id = $this->numObj;

    // store the label->idf relationship, note that this means that labels can be used only once
    $this->destinations["$label"] = $id;
  }

  /**
   * define font families, this is used to initialize the font families for the default fonts
   * and for the user to add new ones for their fonts. The default bahavious can be overridden should
   * that be desired.
   */
  function setFontFamily($family, $options = '') {
    if (!is_array($options)) {
      if ($family === 'init') {
        // set the known family groups
        // these font families will be used to enable bold and italic markers to be included
        // within text streams. html forms will be used... <b></b> <i></i>
        $this->fontFamilies['Helvetica.afm'] =
          array(
            'b'  => 'Helvetica-Bold.afm',
            'i'  => 'Helvetica-Oblique.afm',
            'bi' => 'Helvetica-BoldOblique.afm',
            'ib' => 'Helvetica-BoldOblique.afm'
          );

        $this->fontFamilies['Courier.afm'] =
          array(
            'b'  => 'Courier-Bold.afm',
            'i'  => 'Courier-Oblique.afm',
            'bi' => 'Courier-BoldOblique.afm',
            'ib' => 'Courier-BoldOblique.afm'
          );

        $this->fontFamilies['Times-Roman.afm'] =
          array(
            'b'  => 'Times-Bold.afm',
            'i'  => 'Times-Italic.afm',
            'bi' => 'Times-BoldItalic.afm',
            'ib' => 'Times-BoldItalic.afm'
          );
      }
    } else {

      // the user is trying to set a font family
      // note that this can also be used to set the base ones to something else
      if (mb_strlen($family)) {
        $this->fontFamilies[$family] = $options;
      }
    }
  }

  /**
   * used to add messages for use in debugging
   */
  function addMessage($message) {
    $this->messages.=  $message."\n";
  }

  /**
   * a few functions which should allow the document to be treated transactionally.
   */
  function transaction($action) {
    switch ($action) {
    case 'start':
      // store all the data away into the checkpoint variable
      $data = get_object_vars($this);
      $this->checkpoint = $data;
      unset($data);
      break;

    case 'commit':
      if (is_array($this->checkpoint) && isset($this->checkpoint['checkpoint'])) {
        $tmp = $this->checkpoint['checkpoint'];
        $this->checkpoint = $tmp;
        unset($tmp);
      } else {
        $this->checkpoint = '';
      }
      break;

    case 'rewind':
      // do not destroy the current checkpoint, but move us back to the state then, so that we can try again
      if (is_array($this->checkpoint)) {
        // can only abort if were inside a checkpoint
        $tmp = $this->checkpoint;

        foreach ($tmp as $k => $v) {
          if ($k !== 'checkpoint') {
            $this->$k = $v;
          }
        }
        unset($tmp);
      }
      break;

    case 'abort':
      if (is_array($this->checkpoint)) {
        // can only abort if were inside a checkpoint
        $tmp = $this->checkpoint;
        foreach ($tmp as $k => $v) {
          $this->$k = $v;
        }
        unset($tmp);
      }
      break;
    }
  }
}
