<?php

/**
 * Create pdf documents without additional modules
 *
 * Note that the companion class Document_CezPdf can be used to extend this class and
 * simplify the creation of documents.
 *
 * @category Documents
 * @package	 Document_Cpdf
 * @author   Wayne Munro (inactive) <pdf@ros.co.nz>
 * @author   Lars Olesen <lars@legestue.net>
 * @author   Sune Jensen <sj@sunet.dk>
 * @author   Ole K <ole1986@users.sourceforge.net>
 * @copyright 2007 - 2013 The authors
 * @license   GPL http://www.opensource.org/licenses/gpl-license.php
 * @version  0.11.6
 * @link     http://pdf-php.sf.net
 */
class Cpdf {

    /**
     * allow the programmer to output debug messages on serveral places
     * 'none' = no debug output at all
     * 'error_log' = use error_log
     * 'variable' = store in a variable called $this->messages
     *
     * @default 'error_log'
     */
    public $DEBUG = 'error_log';

    /**
     * Set the debug level
     * E_USER_ERROR = only errors
     * E_USER_WARNING = errors and warning
     * E_USER_NOTICE =  nearly everything
     *
     * @default E_USER_WARNING
     */
    public $DEBUGLEVEL = E_USER_WARNING;

    /**
     * Reversed char string to allow arabic or Hebrew
     */
    public $rtl = false;

    /**
     * flag to validate the output and if output method has be executed
     */
    protected $valid = false;

    /**
     * global defined temporary path used on several places
     */
    public $tempPath = 'tmp/pdf';

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

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

    /**
     * allows object being hashed (affect images only)
     */
    public $hashed = true;

    /**
     * Object hash used to free pdf from redundacies (primary images)
     */
    private $objectHashes = array();

    /**
     * the objectId (number within the objects array) of the document catalog
     *
     * @var integer
     */
    private $catalogId;
    public $targetEncoding = 'iso-8859-1';

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

    /**
     * @var boolean used to either embed or not embed ttf/pfb fonts.
     */
    protected $embedFont = true;

    /**
     * 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.
     *
     * @var array
     */
    private $fontFamilies = array(
        'Helvetica' => array(
            'b' => 'Helvetica-Bold',
            'i' => 'Helvetica-Oblique',
            'bi' => 'Helvetica-BoldOblique',
            'ib' => 'Helvetica-BoldOblique',
        ),
        'Courier' => array(
            'b' => 'Courier-Bold',
            'i' => 'Courier-Oblique',
            'bi' => 'Courier-BoldOblique',
            'ib' => 'Courier-BoldOblique',
        ),
        'Times-Roman' => array(
            'b' => 'Times-Bold',
            'i' => 'Times-Italic',
            'bi' => 'Times-BoldItalic',
            'ib' => 'Times-BoldItalic',
        )
    );

    /**
     * the core fonts to ignore them from unicode
     */
    private $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');

    /**
     * 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
     *
     * @var array
     */
    private $fonts = array();

    /**
     * a record of the current font
     *
     * @var string
     */
    private $currentFont = '';

    /**
     * the current base font
     *
     * @var string
     */
    private $currentBaseFont = '';

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

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

    /**
     * object number of the current page
     *
     * @var integer
     */
    private $currentPage;

    /**
     * object number of the currently active contents block
     */
    private $currentContents;

    /**
     * number of fonts within the system
     */
    private $numFonts = 0;

    /**
     * current colour for fill operations, defaults to inactive value, all three components should be between 0 and 1 inclusive when active
     */
    private $currentColour = array('r' => -1, 'g' => -1, 'b' => -1);

    /**
     * current colour for stroke operations (lines etc.)
     */
    private $currentStrokeColour = array('r' => -1, 'g' => -1, 'b' => -1);

    /**
     * current style that lines are drawn in
     */
    private $currentLineStyle = '';

    /**
     * an array which is used to save the state of the document, mainly the colours and styles
     * it is used to temporarily change to another state, the change back to what it was before
     */
    private $stateStack = array();

    /**
     * number of elements within the state stack
     */
    private $nStateStack = 0;

    /**
     * number of page objects within the document
     */
    private $numPages = 0;

    /**
     * object Id storage stack
     */
    private $stack = array();

    /**
     * number of elements within the object Id storage stack
     */
    private $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
     */
    private $looseObjects = array();

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

    /**
     * the objectId of the information object for the document
     * this contains authorship, title etc.
     */
    private $infoObject = 0;

    /**
     * number of images being tracked within the document
     */
    private $numImages = 0;

    /**
     * an array containing options about the document
     * it defaults to turning on the compression of the objects
     */
    public $options = array('compression' => 7);

    /**
     * the objectId of the first page of the document
     */
    private $firstPageId;

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

    /**
     * track if the current font is bolded or italicised
     */
    private $currentTextState = '';

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

    /**
     * the ancryption array for the document encryption is stored here
     */
    private $arc4 = '';

    /**
     * the object Id of the encryption information
     */
    private $arc4_objnum = 0;

    /**
     * the file identifier, used to uniquely identify a pdf document
     */
    public $fileIdentifier = '';

    /**
     * a flag to say if a document is to be encrypted or not
     *
     * @var boolean
     */
    private $encrypted = 0;

    /**
     * Set the encryption mode 
     * 1 = RC40bit
     * 2 = RC128bit (since PDF Version 1.4)
     */
    private $encryptionMode = 1;

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

    /*
     * encryption padding fetched from the Adobe PDF reference
     */
    private $encryptionPad;

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

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

    /**
     * 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
     *
     * @var array
     */
    private $destinations = array();

    /**
     * store the stack for the transaction commands, each item in here is a record of the values of all the
     * variables 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.
     *
     * @var string
     */
    private $checkpoint = '';

    /**
     * Constructor - starts a new document
     *
     * @param array $pageSize Array of 4 numbers, defining the bottom left and upper right corner of the page. first two are normally zero.
     *
     * @return void
     */
    public function __construct($pageSize = array(0, 0, 612, 792), $isUnicode = false) {
        $this->tempPath = 'tmp/' . FS_TMP_NAME . 'pdf';
        $this->isUnicode = $isUnicode;
        // set the hardcoded encryption pad
        $this->encryptionPad = 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);

        $this->newDocument($pageSize);

        if (in_array('Windows-1252', mb_list_encodings())) {
            $this->targetEncoding = 'Windows-1252';
        }

        // font familys are already known in $this->fontFamilies
        $this->fileIdentifier = md5('ROSPDF');
    }

    /**
     * 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
     * @access private
     */
    private 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;
                break;
        }
    }

    /**
     * sets the viewer preferences
     * @access private
     */
    private 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 'DisplayDocTitle':
                        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;
                break;
        }
    }

    /**
     * define the document catalog, the overall controller for the document
     * @access private
     */
    private 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':
                $o['info'][$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 .= ' /Outlines ' . $v . ' 0 R';
                            break;
                        case 'pages':
                            $res .= ' /Pages ' . $v . ' 0 R';
                            break;
                        case 'viewerPreferences':
                            $res .= ' /ViewerPreferences ' . $o['info']['viewerPreferences'] . ' 0 R';
                            break;
                        case 'openHere':
                            $res .= ' /OpenAction ' . $o['info']['openHere'] . ' 0 R';
                            break;
                    }
                }
                $res .= " >>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * object which is a parent to the pages in the document
     * @access private
     */
    private 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
                break;
            case 'font':
                $o['info']['fonts'][] = array('objNum' => $options['objNum'], 'fontNum' => $options['fontNum']);
                break;
            case 'xObject':
                $o['info']['xObjects'][] = array('objNum' => $options['objNum'], 'label' => $options['label']);
                break;
            case 'out':
                if (count($o['info']['pages'])) {
                    $res = "\n" . $id . " 0 obj\n<< /Type /Pages /Kids [";
                    foreach ($o['info']['pages'] as $k => $v) {
                        $res .= $v . " 0 R ";
                    }
                    $res .= "] /Count " . count($this->objects[$id]['info']['pages']);
                    if ((isset($o['info']['fonts']) && count($o['info']['fonts'])) || isset($o['info']['procset'])) {
                        $res .= " /Resources <<";
                        if (isset($o['info']['procset'])) {
                            $res .= " /ProcSet " . $o['info']['procset'];
                        }
                        if (isset($o['info']['fonts']) && count($o['info']['fonts'])) {
                            $res .= " /Font << ";
                            foreach ($o['info']['fonts'] as $finfo) {
                                $res .= " /F" . $finfo['fontNum'] . " " . $finfo['objNum'] . " 0 R";
                            }
                            $res .= " >>";
                        }
                        if (isset($o['info']['xObjects']) && count($o['info']['xObjects'])) {
                            $res .= " /XObject << ";
                            foreach ($o['info']['xObjects'] as $finfo) {
                                $res .= " /" . $finfo['label'] . " " . $finfo['objNum'] . " 0 R";
                            }
                            $res .= " >>";
                        }
                        $res .= " >>";
                        if (isset($o['info']['mediaBox'])) {
                            $tmp = $o['info']['mediaBox'];
                            $res .= " /MediaBox [" . sprintf('%.3F', $tmp[0]) . ' ' . sprintf('%.3F', $tmp[1]) . ' ' . sprintf('%.3F', $tmp[2]) . ' ' . sprintf('%.3F', $tmp[3]) . ']';
                        }
                    }
                    $res .= " >>\nendobj";
                } else {
                    $res = "\n" . $id . " 0 obj\n<< /Type /Pages\n/Count 0\n>>\nendobj";
                }
                return $res;
                break;
        }
    }

    /**
     * Beta Redirection function
     * @access private
     */
    private function o_redirect($id, $action, $options = '') {
        switch ($action) {
            case 'new':
                $this->objects[$id] = array('t' => 'redirect', 'data' => $options['data'], 'info' => array());
                $this->o_pages($this->currentNode, 'xObject', array('label' => $options['label'], 'objNum' => $id));
                break;
            case 'out':
                $o = & $this->objects[$id];
                $tmp = $o['data'];
                $res = "\n" . $id . " 0 obj\n<<";
                $res .= "/R" . $o['data'] . " " . $o['data'] . " 0 R>>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * defines the outlines in the doc, empty for now
     * @access private
     */
    private 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 $k => $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;
                break;
        }
    }

    /**
     * an object to hold the font description
     * @access private
     */
    private 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->debug('o_font ' . $k . " : " . $v, E_USER_NOTICE);
                            $o['info'][$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 /Subtype /Type0 /BaseFont /" . $o['info']['name'] . "";
                    // The horizontal identity mapping for 2-byte CIDs; may be used
                    // with CIDFonts using any Registry, Ordering, and Supplement values.
                    $res .= " /Encoding /Identity-H /DescendantFonts [" . $o['info']['cidFont'] . " 0 R] /ToUnicode " . $o['info']['toUnicode'] . " 0 R >>\n";
                    $res .= "endobj";
                } else {
                    $res = "\n" . $id . " 0 obj\n<< /Type /Font /Subtype /" . $o['info']['SubType'] . " ";
                    $res .= "/Name /F" . $o['info']['fontNum'] . " ";
                    $res .= "/BaseFont /" . $o['info']['name'] . " ";
                    if (isset($o['info']['encodingDictionary'])) {
                        // then place a reference to the dictionary
                        $res .= "/Encoding " . $o['info']['encodingDictionary'] . " 0 R ";
                    } else if (isset($o['info']['encoding'])) {
                        // use the specified encoding
                        $res .= "/Encoding /" . $o['info']['encoding'] . " ";
                    }
                    if (isset($o['info']['FirstChar'])) {
                        $res .= "/FirstChar " . $o['info']['FirstChar'] . " ";
                    }
                    if (isset($o['info']['LastChar'])) {
                        $res .= "/LastChar " . $o['info']['LastChar'] . " ";
                    }
                    if (isset($o['info']['Widths'])) {
                        $res .= "/Widths " . $o['info']['Widths'] . " 0 R ";
                    }
                    if (isset($o['info']['FontDescriptor'])) {
                        $res .= "/FontDescriptor " . $o['info']['FontDescriptor'] . " 0 R ";
                    }
                    $res .= ">>\nendobj";
                }
                return $res;
                break;
        }
    }

    /**
     * a font descriptor, needed for including additional fonts
     * @access private
     */
    private 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" . $id . " 0 obj\n<< /Type /FontDescriptor ";
                foreach ($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 (strlen($value)) {
                                $res .= '/' . $label . ' ' . $value . " ";
                            }
                            break;
                        case 'FontFile':
                        case 'FontFile2':
                        case 'FontFile3':
                            $res .= '/' . $label . ' ' . $value . " 0 R ";
                            break;
                        case 'FontBBox':
                            $res .= '/' . $label . ' [' . $value[0] . ' ' . $value[1] . ' ' . $value[2] . ' ' . $value[3] . "] ";
                            break;
                        case 'FontName':
                            $res .= '/' . $label . ' /' . $value . " ";
                            break;
                    }
                }
                $res .= ">>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * the font encoding
     * @access private
     */
    private 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" . $id . " 0 obj\n<< /Type /Encoding ";
                if (!isset($o['info']['encoding'])) {
                    $o['info']['encoding'] = 'WinAnsiEncoding';
                }
                if ($o['info']['encoding'] != 'none') {
                    $res .= "/BaseEncoding /" . $o['info']['encoding'] . " ";
                }
                $res .= "/Differences [";
                $onum = -100;
                foreach ($o['info']['differences'] as $num => $label) {
                    if ($num != $onum + 1) {
                        // we cannot make use of consecutive numbering
                        $res .= " " . $num . " /" . $label;
                    } else {
                        $res .= " /" . $label;
                    }
                    $onum = $num;
                }
                $res .= "] >>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * a descendent cid font, needed for unicode fonts
     * @access private
     */
    private 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)"; // A string identifying an issuer of character collections
                $res .= " /Ordering (UCS)"; // A string that uniquely names a character collection issued by a specific registry
                $res .= " /Supplement 0"; // The supplement number of the character collection.
                $res .= " >>";
                $this->objects[$cidSystemInfoId]['c'] = $res;

                // and a CID to GID map
                if ($this->embedFont) {
                    $cidToGidMapId = ++$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->debug("o_fontDescendentCID $k : $v", E_USER_NOTICE);
                            $o['info'][$k] = $v;
                            break;
                    }
                }

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

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

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

                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]";
                }

                if ($this->embedFont) {
                    $res .= " /CIDToGIDMap " . $o['info']['cidToGidMap'] . " 0 R";
                }
                $res .= "  >>\n";
                $res .= "endobj";

                return $res;
        }
    }

    /**
     * a font glyph to character map, needed for unicode fonts
     * @access private
     */
    private 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']);

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

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

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

    /**
     * define the document information
     * @access private
     */
    private 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" . $id . " 0 obj\n<< ";
                foreach ($o['info'] as $k => $v) {
                    $res .= '/' . $k . ' (';
                    if ($this->encrypted) {
                        $res .= $this->filterText($this->ARC4($v), true, false);
                    } else {
                        $res .= $this->filterText($v, true, false);
                    }
                    $res .= ") ";
                }
                $res .= ">>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * an action object, used to link to URLS initially
     * @access private
     */
    private 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':
                        // there will be an 'label' setting, this is the name of the destination
                        $res .= " /S /GoTo /D " . $this->destinations[(string) $o['info']['label']] . " 0 R";
                        break;
                    case 'URI':
                        $res .= " /S /URI /URI (";
                        if ($this->encrypted) {
                            $res .= $this->filterText($this->ARC4($o['info']), true, false);
                        } else {
                            $res .= $this->filterText($o['info'], true, false);
                        }
                        $res .= ")";
                        break;
                }
                $res .= " >>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * an annotation object, this will add an annotation to the current page.
     * initially will support just link annotations
     * @access private
     */
    private 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" . $id . " 0 obj << /Type /Annot";
                switch ($o['info']['type']) {
                    case 'link':
                    case 'ilink':
                        $res .= " /Subtype /Link";
                        break;
                }
                $res .= " /A " . $o['info']['actionId'] . " 0 R";
                $res .= " /Border [0 0 0]";
                $res .= " /H /I";
                $res .= " /Rect [ ";
                foreach ($o['info']['rect'] as $v) {
                    $res .= sprintf("%.4f ", $v);
                }
                $res .= "]";
                $res .= " >>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * a page object, it also creates a contents object to hold its contents
     * @access private
     */
    private 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 shoudl 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 .= " /Parent " . $o['info']['parent'] . " 0 R";
                if (isset($o['info']['annot'])) {
                    $res .= " /Annots [";
                    foreach ($o['info']['annot'] as $aId) {
                        $res .= " " . $aId . " 0 R";
                    }
                    $res .= " ]";
                }
                $count = count($o['info']['contents']);
                if ($count == 1) {
                    $res .= " /Contents " . $o['info']['contents'][0] . " 0 R";
                } else if ($count > 1) {
                    $res .= " /Contents [ ";
                    foreach ($o['info']['contents'] as $cId) {
                        $res .= $cId . " 0 R ";
                    }
                    $res .= "]";
                }
                $res .= " >>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * the contents objects hold all of the content which appears on pages
     * @access private
     */
    private 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 (strlen($options) && intval($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 (function_exists('gzcompress') && $this->options['compression']) {
                        // then implement ZLIB based compression on this content stream
                        $res .= " /Filter /FlateDecode";
                        $tmp = gzcompress($tmp, $this->options['compression']);
                    }
                    if ($this->encrypted) {
                        $this->encryptInit($id);
                        $tmp = $this->ARC4($tmp);
                    }
                    foreach ($o['info'] as $k => $v) {
                        $res .= " /" . $k . ' ' . $v;
                    }
                    $res .= " /Length " . strlen($tmp) . " >> stream\n" . $tmp . "\nendstream";
                }
                $res .= "\nendobj";
                return $res;
                break;
        }
    }

    /**
     * an image object, will be an XObject in the document, includes description and data
     * @access private
     */
    private 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());
                $this->objects[$id]['info']['Type'] = '/XObject';
                $this->objects[$id]['info']['Subtype'] = '/Image';
                $this->objects[$id]['info']['Width'] = $options['iw'];
                $this->objects[$id]['info']['Height'] = $options['ih'];
                if (!isset($options['type']) || $options['type'] == 'jpg') {
                    if (!isset($options['channels'])) {
                        $options['channels'] = 3;
                    }
                    switch ($options['channels']) {
                        case 1:
                            $this->objects[$id]['info']['ColorSpace'] = '/DeviceGray';
                            break;
                        default:
                            $this->objects[$id]['info']['ColorSpace'] = '/DeviceRGB';
                            break;
                    }
                    $this->objects[$id]['info']['Filter'] = '/DCTDecode';
                    $this->objects[$id]['info']['BitsPerComponent'] = 8;
                } else if ($options['type'] == 'png') {
                    if (strlen($options['pdata'])) {
                        $this->numObj++;
                        $this->objects[$this->numObj] = array('t' => 'image', 'c' => '', 'info' => array());
                        $this->objects[$this->numObj]['info'] = array('Type' => '/XObject', 'Subtype' => '/Image', 'Width' => $options['iw'], 'Height' => $options['ih'], 'Filter' => '/FlateDecode', 'ColorSpace' => '/DeviceGray', 'BitsPerComponent' => '8', 'DecodeParms' => '<< /Predictor 15 /Colors 1 /BitsPerComponent 8 /Columns ' . $options['iw'] . ' >>');
                        $this->objects[$this->numObj]['data'] = $options['pdata'];
                        if (isset($options['transparency'])) {
                            switch ($options['transparency']['type']) {
                                case 'indexed':
                                    $tmp = ' [ ' . $options['transparency']['data'] . ' ' . $options['transparency']['data'] . '] ';
                                    $this->objects[$id]['info']['Mask'] = $tmp;
                                    $this->objects[$id]['info']['ColorSpace'] = ' [ /Indexed /DeviceRGB ' . (strlen($options['pdata']) / 3 - 1) . ' ' . $this->numObj . ' 0 R ]';
                                    break;
                                case 'alpha':
                                    $this->objects[$id]['info']['SMask'] = $this->numObj . ' 0 R';
                                    $this->objects[$id]['info']['ColorSpace'] = '/' . $options['color'];
                                    break;
                            }
                        }
                    } else {
                        $this->objects[$id]['info']['ColorSpace'] = '/' . $options['color'];
                    }
                    $this->objects[$id]['info']['BitsPerComponent'] = $options['bitsPerComponent'];
                    $this->objects[$id]['info']['Filter'] = '/FlateDecode';
                    $this->objects[$id]['data'] = $options['data'];
                    $this->objects[$id]['info']['DecodeParms'] = '<< /Predictor 15 /Colors ' . $options['ncolor'] . ' /Columns ' . $options['iw'] . ' /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));
                break;
            case 'out':
                $tmp = $o['data'];
                $res = "\n" . $id . " 0 obj\n<<";
                foreach ($o['info'] as $k => $v) {
                    $res .= " /" . $k . ' ' . $v;
                }
                if ($this->encrypted) {
                    $this->encryptInit($id);
                    $tmp = $this->ARC4($tmp);
                }
                $res .= " /Length " . strlen($tmp) . " >> stream\n" . $tmp . "\nendstream\nendobj";
                return $res;
                break;
        }
    }

    /**
     * encryption object.
     * @access private
     */
    private 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;

                // Pad or truncate the owner password
                $owner = substr($options['owner'] . $this->encryptionPad, 0, 32);
                $user = substr($options['user'] . $this->encryptionPad, 0, 32);

                $this->debug("o_encryption: user password (" . $options['user'] . ") / owner password (" . $options['owner'] . ")");

                // convert permission set into binary string
                $permissions = sprintf("%c%c%c%c", ($options['p'] & 255), (($options['p'] >> 8) & 255), (($options['p'] >> 16) & 255), (($options['p'] >> 24) & 255));

                // Algo 3.3 Owner Password being set into /O Dictionary
                $this->objects[$id]['info']['O'] = $this->encryptOwner($owner, $user);

                // Algo 3.5 User Password - START
                $this->objects[$id]['info']['U'] = $this->encryptUser($user, $this->objects[$id]['info']['O'], $permissions);
                // encryption key is set in encryptUser function
                //$this->encryptionKey = $encryptionKey;

                $this->encrypted = 1;
                break;
            case 'out':
                $res = "\n" . $id . " 0 obj\n<<";
                $res .= ' /Filter /Standard';
                if ($this->encryptionMode > 1) { // RC4 128bit encryption
                    $res .= ' /V 2';
                    $res .= ' /R 3';
                    $res .= ' /Length 128';
                } else { // RC4 40bit encryption
                    $res .= ' /V 1';
                    $res .= ' /R 2';
                }
                // use hex string instead of char code - char codes can make troubles (E.g. CR or LF)
                $res .= ' /O <' . $this->strToHex($o['info']['O']) . '>';
                $res .= ' /U <' . $this->strToHex($o['info']['U']) . '>';
                // and the p-value needs to be converted to account for the twos-complement approach
                //$o['info']['p'] = (($o['info']['p'] ^ 0xFFFFFFFF)+1)*-1;
                $res .= ' /P ' . ($o['info']['p']);
                $res .= " >>\nendobj";
                return $res;
                break;
        }
    }

    /**
     * owner part of the encryption
     * @param $owner - owner password plus padding
     * @param $user - user password plus padding
     * @access private
     */
    private function encryptOwner($owner, $user) {
        $keylength = 5;
        if ($this->encryptionMode > 1) {
            $keylength = 16;
        }

        $ownerHash = $this->md5_16($owner); // PDF 1.4 - repeat this 50 times in revision 3
        if ($this->encryptionMode > 1) { // if it is the RC4 128bit encryption
            for ($i = 0; $i < 50; $i++) {
                $ownerHash = $this->md5_16($ownerHash);
            }
        }

        $ownerKey = substr($ownerHash, 0, $keylength); // PDF 1.4 - Create the encryption key (IMPORTANT: need to check Length)

        $this->ARC4_init($ownerKey); // 5 bytes of the encryption key (hashed 50 times)
        $ovalue = $this->ARC4($user); // PDF 1.4 - Encrypt the padded user password using RC4

        if ($this->encryptionMode > 1) {
            $len = strlen($ownerKey);
            for ($i = 1; $i <= 19; ++$i) {
                $ek = '';
                for ($j = 0; $j < $len; $j++) {
                    $ek .= chr(ord($ownerKey[$j]) ^ $i);
                }
                $this->ARC4_init($ek);
                $ovalue = $this->ARC4($ovalue);
            }
        }
        return $ovalue;
    }

    /**
     * 
     * user part of the encryption
     * @param $user - user password plus padding
     * @param $ownerDict - encrypted owner entry
     * @param $permissions - permission set (print, copy, modify, ...)
     */
    function encryptUser($user, $ownerDict, $permissions) {
        $keylength = 5;
        if ($this->encryptionMode > 1) {
            $keylength = 16;
        }
        // make hash with user, encrypted owner, permission set and fileIdentifier
        $hash = $this->md5_16($user . $ownerDict . $permissions . $this->hexToStr($this->fileIdentifier));

        // loop thru the hash process when it is revision 3 of encryption routine (usually RC4 128bit)
        if ($this->encryptionMode > 1) {
            for ($i = 0; $i < 50; ++$i) {
                $hash = $this->md5_16(substr($hash, 0, $keylength)); // use only length of encryption key from the previous hash
            }
        }

        $this->encryptionKey = substr($hash, 0, $keylength); // PDF 1.4 - Create the encryption key (IMPORTANT: need to check Length)

        if ($this->encryptionMode > 1) { // if it is the RC4 128bit encryption
            // make a md5 hash from padding string (hardcoded by Adobe) and the fileIdenfier
            $userHash = $this->md5_16($this->encryptionPad . $this->hexToStr($this->fileIdentifier));

            // encrypt the hash from the previous method by using the encryptionKey
            $this->ARC4_init($this->encryptionKey);
            $uvalue = $this->ARC4($userHash);

            $len = strlen($this->encryptionKey);
            for ($i = 1; $i <= 19; ++$i) {
                $ek = '';
                for ($j = 0; $j < $len; $j++) {
                    $ek .= chr(ord($this->encryptionKey[$j]) ^ $i);
                }
                $this->ARC4_init($ek);
                $uvalue = $this->ARC4($uvalue);
            }
            $uvalue .= substr($this->encryptionPad, 0, 16);

            //$this->encryptionKey = $encryptionKey;
        } else { // if it is the RC4 40bit encryption
            $this->ARC4_init($this->encryptionKey);
            //$this->encryptionKey = $encryptionKey;
            //$this->encrypted=1;
            $uvalue = $this->ARC4($this->encryptionPad);
        }
        return $uvalue;
    }

    /**
     * internal method to convert string to hexstring (used for owner and user dictionary)
     * @param $string - any string value
     * @access protected
     */
    protected function strToHex($string) {
        $hex = '';
        for ($i = 0; $i < strlen($string); $i++)
            $hex .= sprintf("%02x", ord($string[$i]));
        return $hex;
    }

    protected function hexToStr($hex) {
        $str = '';
        for ($i = 0; $i < strlen($hex); $i += 2)
            $str .= chr(hexdec(substr($hex, $i, 2)));
        return $str;
    }

    /**
     * calculate the 16 byte version of the 128 bit md5 digest of the string
     * @access private
     */
    private function md5_16($string) {
        $tmp = md5($string);
        $out = pack("H*", $tmp);
        return $out;
    }

    /**
     * initialize the encryption for processing a particular object
     * @access private
     */
    private function encryptInit($id) {
        $tmp = $this->encryptionKey;
        $hex = dechex($id);
        if (strlen($hex) < 6) {
            $hex = substr('000000', 0, 6 - strlen($hex)) . $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);
        if ($this->encryptionMode > 1) {
            $this->ARC4_init(substr($key, 0, 16)); // use max 16 bytes for RC4 128bit encryption key
        } else {
            $this->ARC4_init(substr($key, 0, 10)); // use (n + 5 bytes) for RC4 40bit encryption key
        }
    }

    /**
     * initialize the ARC4 encryption
     * @access private
     */
    private function ARC4_init($key = '') {
        $this->arc4 = '';
        // setup the control array
        if (strlen($key) == 0) {
            return;
        }
        $k = '';
        while (strlen($k) < 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
     * @access private
     */
    private function ARC4($text) {
        $len = strlen($text);
        $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;
    }

    /**
     * add a link in the document to an external URL
     * @access public
     */
    public 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)
     * @access public
     */
    public 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
     * @access public
     */
    public function setEncryption($userPass = '', $ownerPass = '', $pc = array(), $mode = 1) {
        if ($mode > 1) {
            $p = bindec('01111111111111111111000011000000'); // revision 3 is using bit 3 - 6 AND 9 - 12
        } else {
            $p = bindec('01111111111111111111111111000000'); // while revision 2 is using bit 3 - 6 only
        }

        $options = array(
            'print' => 4
            , 'modify' => 8
            , 'copy' => 16
            , 'add' => 32
            , 'fill' => 256
            , 'extract' => 512
            , 'assemble' => 1024
            , 'represent' => 2048
        );
        foreach ($pc as $k => $v) {
            if ($v && isset($options[$k])) {
                $p += $options[$k];
            } else if (isset($options[$v])) {
                $p += $options[$v];
            }
        }

        // set the encryption mode to either RC4 40bit or RC4 128bit
        $this->encryptionMode = $mode;

        // implement encryption on the document
        if ($this->arc4_objnum == 0) {
            // then the block does not exist already, add it.
            $this->numObj++;
            if (strlen($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
     * @access public
     */
    function checkAllHere() {
        // set the validation flag to true when everything is ok.
        // currently it only checks if output function has been called
        $this->valid = true;
    }

    /**
     * return the pdf stream as a string returned from the function
     * This method is protect to force user to use ezOutput from Cezpdf.php
     * @access protected
     */
    function output($debug = 0) {

        if ($debug) {
            // turn compression off
            $this->options['compression'] = 0;
        }

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

        if ($this->valid) {
            $this->debug('The output method has been executed again', E_USER_WARNING);
        }

        $this->checkAllHere();

        $xref = array();
        $content = "%PDF-1.4\n%����";
        //  $content="%PDF-1.3\n";
        $pos = strlen($content);
        foreach ($this->objects as $k => $v) {
            $tmp = 'o_' . $v['t'];
            $cont = $this->$tmp($k, 'out');
            $content .= $cont;
            $xref[] = $pos;
            $pos += strlen($cont);
        }
        ++$pos;
        $content .= "\nxref\n0 " . (count($xref) + 1) . "\n0000000000 65535 f \n";
        foreach ($xref as $p) {
            $content .= substr('0000000000', 0, 10 - strlen($p + 1)) . ($p + 1) . " 00000 n \n";
        }
        $content .= "trailer\n<< /Size " . (count($xref) + 1) . " /Root 1 0 R /Info " . $this->infoObject . " 0 R";
        // if encryption has been applied to this document then add the marker for this dictionary
        if ($this->arc4_objnum > 0) {
            $content .= " /Encrypt " . $this->arc4_objnum . " 0 R";
        }
        if (strlen($this->fileIdentifier)) {
            $content .= " /ID[<" . $this->fileIdentifier . "><" . $this->fileIdentifier . ">]";
        }
        $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
     *
     * @access protected
     */
    protected 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;

        $this->o_pages($this->numObj, 'procset', '[/PDF/TEXT/ImageB/ImageC/ImageI]');

        $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.
     *
     * @param string $font Font name (can contain both path and extension)
     *
     * @return void
     */
    protected function openFont($font) {
        // assume that $font contains both the path and perhaps the extension to the file, split them
        $pos = strrpos($font, '/');
        if ($pos === false) {
            // $dir  = './';
            $dir = dirname(__FILE__) . '/fonts/';
            $name = $font;
        } else {
            $dir = substr($font, 0, $pos + 1);
            $name = substr($font, $pos + 1);
        }

        //if (substr($name, -4) == '.afm' || substr($name, -4) == '.ufm') {
        //$name = substr($name, 0, strlen($name) - 4);
        //}

        if (!$this->isUnicode) {
            $metrics_name = "$name.afm";
        } else {
            $metrics_name = "$name.ufm";
        }

        $this->debug('openFont executed: ' . $font . ' - ' . $name . ' / IsUnicode: ' . $this->isUnicode);

        $cachedFile = 'cached' . $metrics_name . '.php';

        // use the temp folder to read/write cached font data
        if (file_exists($this->tempPath . '/' . $cachedFile)) {
            $this->debug('openFont: ' . $this->tempPath . '/' . $cachedFile . ' already exist');
            //$tmp = file($this->tempPath.'/'.$cachedFile);
            $this->fonts[$font] = require($this->tempPath . '/' . $cachedFile);
            if (!isset($this->fonts[$font]['_version_']) || $this->fonts[$font]['_version_'] < 2) {
                // if the font file is old, then clear it out and prepare for re-creation
                $this->debug('openFont: clear out, make way for new version.');
                unset($this->fonts[$font]);
            }
        }
        if (!isset($this->fonts[$font]) && file_exists($dir . $metrics_name)) {
            // then rebuild the php_<font>.afm file from the <font>.afm file
            $this->debug('openFont: (re)create ' . $cachedFile);
            $data = array();
            // set unicode to true ufm file is used
            $data['isUnicode'] = (strtolower(substr($metrics_name, -3)) !== 'afm');

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

            $file = file($dir . $metrics_name);
            foreach ($file as $row) {
                $row = trim($row);
                $pos = strpos($row, ' ');
                if ($pos) {
                    // then there must be some keyword
                    $key = substr($row, 0, $pos);
                    switch ($key) {
                        case 'FontName':
                        case 'FullName':
                        case 'FamilyName':
                        case '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':
                            $data[$key] = trim(substr($row, $pos));
                            break;
                        case 'FontBBox':
                            $data[$key] = explode(' ', trim(substr($row, $pos)));
                            break;
                        case 'C':
                            // C 39 ; WX 222 ; N quoteright ; B 53 463 157 718 ;
                            // use preg_match instead to improve performace
                            // IMPORTANT: if "L i fi ; L l fl ;" is required preg_match must be amended
                            $r = preg_match('/C (-?\d+) ; WX (-?\d+) ; N (\w+) ; B (-?\d+) (-?\d+) (-?\d+) (-?\d+) ;/', $row, $m);
                            if ($r == 1) {
                                //$dtmp = array('C'=> $m[1],'WX'=> $m[2], 'N' => $m[3], 'B' => array($m[4], $m[5], $m[6], $m[7]));
                                $c = (int) $m[1];
                                $n = $m[3];
                                $width = floatval($m[2]);

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

                            $r = preg_match('/U (-?\d+) ; WX (-?\d+) ; N (\w+) ; G (-?\d+) ;/', $row, $m);

                            if ($r == 1) {
                                //$dtmp = array('U'=> $m[1],'WX'=> $m[2], 'N' => $m[3], 'G' => $m[4]);
                                $c = (int) $m[1];
                                $n = $m[3];
                                $glyph = $m[4];
                                $width = floatval($m[2]);

                                if ($c >= 0) {
                                    if ($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;
                            // KPX Adieresis yacute -40
                            $bits = explode(' ', $row);
                            $data['KPX'][$bits[1]][$bits[2]] = $bits[3];
                            break;
                    }
                }
            }

            $data['CIDtoGID'] = base64_encode($cidtogid);
            $data['_version_'] = 2;

            $this->fonts[$font] = $data;
            $fp = fopen($this->tempPath . '/' . $cachedFile, 'w'); // use the temp folder to write cached font data
            fwrite($fp, '<?php /* R&OS php pdf class font cache file */ return ' . var_export($data, true) . '; ?>');
            fclose($fp);
        } else if (!isset($this->fonts[$font])) {
            $this->debug(sprintf('openFont: no font file found for "' . $font . '" IsUnicode: %b', $font, $this->isUnicode), E_USER_WARNING);
        }
    }

    /**
     * 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.
     *
     * @param string  $fontName Name of the font
     * @param string  $encoding Which encoding to use
     * @param integer $set      What is this
     *
     * @return void
     * @access public
     */
    public function selectFont($fontName, $encoding = '', $set = 1) {
        $ext = substr($fontName, -4);
        if ($ext === '.afm' || $ext === '.ufm') {
            $fontName = substr($fontName, 0, strlen($fontName) - 4);
        }

        $pos = strrpos($fontName, '/');
        if ($pos !== false) {
            $name = substr($fontName, $pos + 1);
        } else {
            $name = $fontName;
        }

        if (!isset($this->fonts[$fontName])) {
            // load the file
            $this->openFont($fontName);
            if (isset($this->fonts[$fontName])) {
                $this->numObj++;
                $this->numFonts++;

                $font = &$this->fonts[$fontName];
                $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'] = $encoding['differences'];
                    }
                } else if (strlen($encoding)) {
                    // 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

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

                $fbfile = $fontName . '.' . $fbtype;

                if ($fbtype) {
                    $adobeFontName = $font['FontName'];
                    // $fontObj = $this->numObj;
                    $this->debug('selectFont: adding font file "' . $fbfile . '" to pdf');
                    // find the array of fond 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']) {
                                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 > $lastChar) {
                                for ($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->debug('selectFont: FirstChar=' . $firstChar);
                    $this->debug('selectFont: LastChar=' . $lastChar);

                    $widthid = -1;

                    if (!$font['isUnicode']) {
                        $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.
                    if ($this->embedFont) {
                        if (!$this->isUnicode || $fbtype !== 'ttf') {
                            $data = file_get_contents($fbfile);
                        } else {
                            $data = file_get_contents($fbfile);
                            ;
                        }
                    }

                    // 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' => 'CapHeight', '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 ($this->embedFont) {
                        if ($fbtype == 'pfb') {
                            $fdopt['FontFile'] = $pfbid;
                        } else if ($fbtype == 'ttf' && $this->embedFont) {
                            $fdopt['FontFile2'] = $pfbid;
                        }
                    }

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

                    // embed the font program
                    if ($this->embedFont) {
                        $this->o_contents($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;
                            $l3 = strlen($data) - $l2 - $l1;
                            $this->o_contents($this->numObj, 'add', array('Length1' => $l1, 'Length2' => $l2, 'Length3' => $l3));
                        } else if ($fbtype == 'ttf') {
                            $l1 = strlen($data);
                            $this->o_contents($this->numObj, 'add', array('Length1' => $l1));
                        }
                    }

                    // tell the font object about all this new stuff
                    $tmp = array('BaseFont' => $adobeFontName, 'Widths' => $widthid
                        , 'FirstChar' => $firstChar, 'LastChar' => $lastChar
                        , 'FontDescriptor' => $fontDescriptorId);
                    if ($fbtype == 'ttf') {
                        $tmp['SubType'] = 'TrueType';
                    }
                    $this->debug('selectFont: adding extra info to font.(' . $fontObj . ')');
                    foreach ($tmp as $fk => $fv) {
                        $this->debug($fk . " : " . $fv);
                    }
                    $this->o_font($fontObj, 'add', $tmp);
                } else if (!in_array(strtolower($name), $this->coreFonts)) {
                    $this->debug('selectFont: No pfb/ttf file found for "' . $name . '"', E_USER_WARNING);
                }


                // 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 line means that if a new font is selected, then the current text state will be
            // applied to it as well.
            $this->setCurrentFont();
        }
        return $this->currentFontNum;
    }

    /**
     * sets up the current font, based on the font families, and the current text state
     * note that this system is quite flexible, a <b><i> font can be completely different to a
     * <i><b> font, and even <b><b> 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.
     *
     * @access protected
     */
    protected function setCurrentFont() {
        if (strlen($this->currentBaseFont) == 0) {
            // then assume an initial font
            $this->selectFont(dirname(__FILE__) . '/fonts/Helvetica');
        }
        $pos = strrpos($this->currentBaseFont, '/');
        if ($pos !== false) {
            $cf = substr($this->currentBaseFont, $pos + 1);
        } else {
            $cf = $this->currentBaseFont;
        }
        if (strlen($this->currentTextState) && isset($this->fontFamilies[$cf]) && isset($this->fontFamilies[$cf][$this->currentTextState])) {
            // then we are in some state or another
            // and this font has a family, and the current setting exists within it
            // select the font, then return it
            if ($pos !== false) {
                $nf = substr($this->currentBaseFont, 0, strrpos($this->currentBaseFont, '/') + 1) . $this->fontFamilies[$cf][$this->currentTextState];
            } else {
                $nf = $this->fontFamilies[$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.
     * @access protected
     */
    protected function getFirstPageId() {
        return $this->firstPageId;
    }

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

    /**
     * sets the colour for fill operations
     * @access public
     */
    public function setColor($r, $g, $b, $force = 0) {
        if ($r >= 0 && ($force || $r != $this->currentColour['r'] || $g != $this->currentColour['g'] || $b != $this->currentColour['b'])) {
            $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $r) . ' ' . sprintf('%.3F', $g) . ' ' . sprintf('%.3F', $b) . ' rg';
            $this->currentColour = array('r' => $r, 'g' => $g, 'b' => $b);
        }
    }

    /**
     * sets the colour for stroke operations
     * @access public
     */
    public function setStrokeColor($r, $g, $b, $force = 0) {
        if ($r >= 0 && ($force || $r != $this->currentStrokeColour['r'] || $g != $this->currentStrokeColour['g'] || $b != $this->currentStrokeColour['b'])) {
            $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $r) . ' ' . sprintf('%.3F', $g) . ' ' . sprintf('%.3F', $b) . ' RG';
            $this->currentStrokeColour = array('r' => $r, 'g' => $g, 'b' => $b);
        }
    }

    /**
     * draw a line from one set of coordinates to another
     * @access public
     */
    public function line($x1, $y1, $x2, $y2) {
        $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $x1) . ' ' . sprintf('%.3F', $y1) . ' m ' . sprintf('%.3F', $x2) . ' ' . sprintf('%.3F', $y2) . ' l S';
    }

    /**
     * draw a bezier curve based on 4 control points
     * @access public
     */
    public 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.
        $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $x0) . ' ' . sprintf('%.3F', $y0) . ' m ' . sprintf('%.3F', $x1) . ' ' . sprintf('%.3F', $y1);
        $this->objects[$this->currentContents]['c'] .= ' ' . sprintf('%.3F', $x2) . ' ' . sprintf('%.3F', $y2) . ' ' . sprintf('%.3F', $x3) . ' ' . sprintf('%.3F', $y3) . ' c S';
    }

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

    /**
     * draw a filled ellipse
     * @access public
     */
    public function filledEllipse($x0, $y0, $r1, $r2 = 0, $angle = 0, $nSeg = 8, $astart = 0, $afinish = 360) {
        return $this->ellipse($x0, $y0, $r1, $r2 = 0, $angle, $nSeg, $astart, $afinish, 1, 1);
    }

    /**
     * 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 $r2 is not set, then a circle is drawn
     * nSeg is not allowed to be less than 2, as this will simply draw a line (and will even draw a
     * pretty crappy shape at 2, as we are approximating with bezier curves.
     * @access public
     */
    public function ellipse($x0, $y0, $r1, $r2 = 0, $angle = 0, $nSeg = 8, $astart = 0, $afinish = 360, $close = 1, $fill = 0) {
        if ($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);
            $tmp = "\n q ";
            $tmp .= sprintf('%.3F', cos($a)) . ' ' . sprintf('%.3F', (-1.0 * sin($a))) . ' ' . sprintf('%.3F', sin($a)) . ' ' . sprintf('%.3F', cos($a)) . ' ';
            $tmp .= sprintf('%.3F', $x0) . ' ' . sprintf('%.3F', $y0) . ' cm';
            $this->objects[$this->currentContents]['c'] .= $tmp;
            $x0 = 0;
            $y0 = 0;
        }

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

        $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $a0) . ' ' . sprintf('%.3F', $b0) . ' m ';
        for ($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);
            $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', ($a0 + $c0 * $dtm)) . ' ' . sprintf('%.3F', ($b0 + $d0 * $dtm));
            $this->objects[$this->currentContents]['c'] .= ' ' . sprintf('%.3F', ($a1 - $c1 * $dtm)) . ' ' . sprintf('%.3F', ($b1 - $d1 * $dtm)) . ' ' . sprintf('%.3F', $a1) . ' ' . sprintf('%.3F', $b1) . ' c';
            $a0 = $a1;
            $b0 = $b1;
            $c0 = $c1;
            $d0 = $d1;
        }
        if ($fill) {
            $this->objects[$this->currentContents]['c'] .= ' f';
        } else {
            if ($close) {
                $this->objects[$this->currentContents]['c'] .= ' s'; // small 's' signifies closing the path as well
            } else {
                $this->objects[$this->currentContents]['c'] .= ' S';
            }
        }
        if ($angle != 0) {
            $this->objects[$this->currentContents]['c'] .= ' 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.
     * @access public
     */
    public 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)) {
            $string .= ' [';
            foreach ($dash as $len) {
                $string .= ' ' . $len;
            }
            $string .= ' ] ' . $phase . ' d';
        }
        $this->currentLineStyle = $string;
        $this->objects[$this->currentContents]['c'] .= "\n" . $string;
    }

    /**
     * draw a polygon, the syntax for this is similar to the GD polygon command
     * @access public
     */
    public function polygon($p, $np, $f = 0) {
        $this->objects[$this->currentContents]['c'] .= "\n";
        $this->objects[$this->currentContents]['c'] .= sprintf('%.3F', $p[0]) . ' ' . sprintf('%.3F', $p[1]) . ' m ';
        for ($i = 2; $i < $np * 2; $i = $i + 2) {
            $this->objects[$this->currentContents]['c'] .= sprintf('%.3F', $p[$i]) . ' ' . sprintf('%.3F', $p[$i + 1]) . ' l ';
        }
        if ($f == 1) {
            $this->objects[$this->currentContents]['c'] .= ' f';
        } else {
            $this->objects[$this->currentContents]['c'] .= ' 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
     * @access public
     */
    public function filledRectangle($x1, $y1, $width, $height) {
        $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $x1) . ' ' . sprintf('%.3F', $y1) . ' ' . sprintf('%.3F', $width) . ' ' . sprintf('%.3F', $height) . ' re f';
    }

    /**
     * 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
     * @access public 
     */
    public function rectangle($x1, $y1, $width, $height) {
        $this->objects[$this->currentContents]['c'] .= "\n" . sprintf('%.3F', $x1) . ' ' . sprintf('%.3F', $y1) . ' ' . sprintf('%.3F', $width) . ' ' . sprintf('%.3F', $height) . ' re S';
    }

    /**
     * add a new page to the document
     * this also makes the new page the current active object
     * @access public
     */
    public 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 od 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 colour set, then transfer them
        if ($this->currentColour['r'] >= 0) {
            $this->setColor($this->currentColour['r'], $this->currentColour['g'], $this->currentColour['b'], 1);
        }
        if ($this->currentStrokeColour['r'] >= 0) {
            $this->setStrokeColor($this->currentStrokeColour['r'], $this->currentStrokeColour['g'], $this->currentStrokeColour['b'], 1);
        }

        // if there is a line style set, then put this in too
        if (strlen($this->currentLineStyle)) {
            $this->objects[$this->currentContents]['c'] .= "\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
     * this method is protected to force user to use ezStream method from Cezpdf.php
     * @access protected
     */
    protected function stream($options = '') {
        // setting the options allows the adjustment of the headers
        // values at the moment are:
        // 'Content-Disposition'=>'filename'  - sets the filename, though not too sure how well this will
        //        work as in my trial the browser seems to use the filename of the php file with .pdf on the end
        // 'Accept-Ranges'=>1 or 0 - if this is not set to 1, then this header is not included, off by default
        //    this header seems to have caused some problems despite tha fact that it is supposed to solve
        //    them, so I am leaving it off by default.
        // 'compress'=> 1 or 0 - apply content stream compression, this is on (1) by default
        // 'download'=> 1 or 0 - provide download dialog
        if (!is_array($options)) {
            $options = array();
        }
        if (isset($options['compress']) && $options['compress'] == 0) {
            $tmp = $this->output(1);
        } else {
            $tmp = $this->output();
        }
        header("Content-type: application/pdf");
        header("Content-Length: " . strlen(ltrim($tmp)));
        $fileName = (isset($options['Content-Disposition']) ? $options['Content-Disposition'] : 'file.pdf');
        if (isset($options['download']) && $options['download'] == 1)
            $attached = 'attachment';
        else
            $attached = 'inline';
        header("Content-Disposition: $attached; filename=" . $fileName);
        if (isset($options['Accept-Ranges']) && $options['Accept-Ranges'] == 1) {
            header("Accept-Ranges: " . strlen(ltrim($tmp)));
        }
        echo ltrim($tmp);
    }

    /**
     * return the height in units of the current font in the given size
     * @access public
     */
    public function getFontHeight($size) {
        if (!$this->numFonts) {
            $this->selectFont('./fonts/Helvetica');
        }

        $font = &$this->fonts[$this->currentFont];
        // for the current font, and the given size, what is the height of the font in user units
        $h = $font['FontBBox'][3] - $font['FontBBox'][1];
        return $size * $h / 1000;
    }

    /**
     * return the font decender, 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
     * @access public
     */
    public function getFontDecender($size) {
        // note that this will most likely return a negative value
        if (!$this->numFonts) {
            $this->selectFont('./fonts/Helvetica');
        }
        $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 protected
     */
    protected function filterText($text, $bom = true, $convert_encoding = true) {

        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, $this->targetEncoding, 'UTF-8');
            }
        }

        $text = strtr($text, array(')' => '\\)', '(' => '\\(', '\\' => '\\\\', chr(8) => '\\b', chr(9) => '\\t', chr(10) => '\\n', chr(12) => '\\f', chr(13) => '\\r'));

        if ($this->rtl) {
            $text = strrev($text);
        }

        return $text;
    }

    /**
     * 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 $text UTF-8 string to process
     * @return array UTF-8 codepoints array for the string
     */
    private function utf8toCodePointsArray(&$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 $bom whether to add the byte order marker
     * @return string UTF-16 result string
     */
    private function utf8toUtf16BE(&$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
     *
     * @access protected
     */
    protected 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);
    }

    /**
     * wrapper function for checkTextDirective1
     *
     * @access private
     */
    private function checkTextDirective(&$text, $i, &$f) {
        $x = 0;
        $y = 0;
        return $this->checkTextDirective1($text, $i, $f, 0, $x, $y);
    }

    /**
     * checks if the text stream contains a control directive
     * if so then makes some changes and returns the number of characters involved in the directive
     * this has been re-worked to include everything neccesary to fins the current writing point, so that
     * the location can be sent to the callback function if required
     * if the directive does not require a font change, then $f should be set to 0
     *
     * @access private
     */
    private function checkTextDirective1(&$text, $i, &$f, $final, &$x, &$y, $size = 0, $angle = 0, $wordSpaceAdjust = 0) {
        $directive = 0;
        $j = $i;
        if ($text[$j] == '<') {
            $j++;
            switch ($text[$j]) {
                case '/':
                    $j++;
                    if (strlen($text) <= $j) {
                        return $directive;
                    }
                    switch ($text[$j]) {
                        case 'b':
                        case 'i':
                            $j++;
                            if ($text[$j] == '>') {
                                $p = strrpos($this->currentTextState, $text[$j - 1]);
                                if ($p !== false) {
                                    // then there is one to remove
                                    $this->currentTextState = substr($this->currentTextState, 0, $p) . substr($this->currentTextState, $p + 1);
                                }
                                $directive = $j - $i + 1;
                            }
                            break;
                        case 'c':
                            // this this might be a callback function
                            $j++;
                            $k = strpos($text, '>', $j);
                            if ($k !== false && $text[$j] == ':') {
                                // then this will be treated as a callback directive
                                $directive = $k - $i + 1;
                                $f = 0;
                                // split the remainder on colons to get the function name and the paramater
                                $tmp = substr($text, $j + 1, $k - $j - 1);
                                $b1 = strpos($tmp, ':');
                                if ($b1 !== false) {
                                    $func = substr($tmp, 0, $b1);
                                    $parm = substr($tmp, $b1 + 1);
                                } else {
                                    $func = $tmp;
                                    $parm = '';
                                }
                                if (!isset($func) || !strlen(trim($func))) {
                                    $directive = 0;
                                } else {
                                    // only call the function if this is the final call
                                    if ($final) {
                                        // need to assess the text position, calculate the text width to this point
                                        // can use getTextWidth to find the text width I think
                                        $tmp = $this->getTextPosition($x, $y, $angle, $size, $wordSpaceAdjust, substr($text, 0, $i));
                                        $info = array('x' => $tmp[0], 'y' => $tmp[1], 'angle' => $angle, 'status' => 'end', 'p' => $parm, 'nCallback' => $this->nCallback);
                                        $x = $tmp[0];
                                        $y = $tmp[1];
                                        $ret = $this->$func($info);
                                        if (is_array($ret)) {
                                            // then the return from the callback function could set the position, to start with, later will do font colour, and font
                                            foreach ($ret as $rk => $rv) {
                                                switch ($rk) {
                                                    case 'x':
                                                    case 'y':
                                                        $$rk = $rv;
                                                        break;
                                                }
                                            }
                                        }
                                        // also remove from to the stack
                                        // for simplicity, just take from the end, fix this another day
                                        $this->nCallback--;
                                        if ($this->nCallback < 0) {
                                            $this->nCallBack = 0;
                                        }
                                    }
                                }
                            }
                            break;
                    }
                    break;
                case 'b':
                case 'i':
                    $j++;
                    if ($text[$j] == '>') {
                        $this->currentTextState .= $text[$j - 1];
                        $directive = $j - $i + 1;
                    }
                    break;
                case 'C':
                    $noClose = 1;
                case 'c':
                    // this this might be a callback function
                    $j++;
                    $k = strpos($text, '>', $j);
                    if ($k !== false && $text[$j] == ':') {
                        // then this will be treated as a callback directive
                        $directive = $k - $i + 1;
                        $f = 0;
                        // split the remainder on colons to get the function name and the paramater
                        // $bits = explode(':',substr($text,$j+1,$k-$j-1));
                        $tmp = substr($text, $j + 1, $k - $j - 1);
                        $b1 = strpos($tmp, ':');
                        if ($b1 !== false) {
                            $func = substr($tmp, 0, $b1);
                            $parm = substr($tmp, $b1 + 1);
                        } else {
                            $func = $tmp;
                            $parm = '';
                        }
                        if (!isset($func) || !strlen(trim($func))) {
                            $directive = 0;
                        } else {
                            // only call the function if this is the final call, ie, the one actually doing printing, not measurement
                            if ($final) {
                                // need to assess the text position, calculate the text width to this point
                                // can use getTextWidth to find the text width I think
                                // also add the text height and decender
                                $tmp = $this->getTextPosition($x, $y, $angle, $size, $wordSpaceAdjust, substr($text, 0, $i));
                                $info = array('x' => $tmp[0], 'y' => $tmp[1], 'angle' => $angle, 'status' => 'start', 'p' => $parm, 'f' => $func, 'height' => $this->getFontHeight($size), 'decender' => $this->getFontDecender($size));
                                $x = $tmp[0];
                                $y = $tmp[1];
                                if (!isset($noClose) || !$noClose) {
                                    // only add to the stack if this is a small 'c', therefore is a start-stop pair
                                    $this->nCallback++;
                                    $info['nCallback'] = $this->nCallback;
                                    $this->callback[$this->nCallback] = $info;
                                }
                                $ret = $this->$func($info);
                                if (is_array($ret)) {
                                    // then the return from the callback function could set the position, to start with, later will do font colour, and font
                                    foreach ($ret as $rk => $rv) {
                                        switch ($rk) {
                                            case 'x':
                                            case 'y':
                                                $$rk = $rv;
                                                break;
                                        }
                                    }
                                }
                            }
                        }
                    }
                    break;
            }
        }
        return $directive;
    }

    /**
     * add text to the document, at a specified location, size and angle on the page
     * @access public
     */
    public function addText($x, $y, $size, $text, $angle = 0, $wordSpaceAdjust = 0) {
        if (!$this->numFonts) {
            $this->selectFont(dirname(__FILE__) . '/fonts/Helvetica');
        }

        // 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'], 'decender' => $this->callback[$i]['decender']);
                $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));
        }

        $len = strlen($text);
        $start = 0;
        for ($i = 0; $i < $len; $i++) {
            $f = 1;
            $directive = $this->checkTextDirective($text, $i, $f);
            if ($directive) {
                // then we should write what we need to
                if ($i > $start) {
                    $part = substr($text, $start, $i - $start);
                    $this->addContent(' /F' . $this->currentFontNum . ' ' . sprintf('%.1f', $size) . ' Tf ');
                    $this->addContent(' (' . $this->filterText($part, false) . ') Tj');
                }
                if ($f) {
                    // then there was nothing drastic done here, restore the contents
                    $this->setCurrentFont();
                } else {
                    $this->addContent(' ET');
                    $f = 1;
                    $xp = $x;
                    $yp = $y;
                    $directive = $this->checkTextDirective1($text, $i, $f, 1, $xp, $yp, $size, $angle, $wordSpaceAdjust);

                    // restart the text object
                    if ($angle == 0) {
                        $this->addContent("\n" . 'BT ' . sprintf('%.3F', $xp) . ' ' . sprintf('%.3F', $yp) . ' Td');
                    } else {
                        $a = deg2rad((float) $angle);
                        $tmp = "\n" . 'BT ';
                        $tmp .= sprintf('%.3F', cos($a)) . ' ' . sprintf('%.3F', (-1.0 * sin($a))) . ' ' . sprintf('%.3F', sin($a)) . ' ' . sprintf('%.3F', cos($a)) . ' ';
                        $tmp .= sprintf('%.3F', $xp) . ' ' . sprintf('%.3F', $yp) . ' Tm';
                        $this->addContent($tmp);
                    }
                    if ($wordSpaceAdjust != 0 || $wordSpaceAdjust != $this->wordSpaceAdjust) {
                        $this->wordSpaceAdjust = $wordSpaceAdjust;
                        $this->addContent(' ' . sprintf('%.3F', $wordSpaceAdjust) . ' Tw');
                    }
                }
                // and move the writing point to the next piece of text
                $i = $i + $directive - 1;
                $start = $i + 1;
            }
        }

        if ($start < $len) {
            $part = substr($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;
                $place_text = str_replace(' ', ' ) ' . (-round($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 alse used by the other class functions
     * @access public
     */
    public function getTextWidth($size, $text) {
        // 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('./fonts/Helvetica');
        }

        // 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;
        $len = strlen($text);
        $cf = $this->currentFont;
        for ($i = 0; $i < $len; $i++) {
            $f = 1;
            $directive = $this->checkTextDirective($text, $i, $f);
            if ($directive) {
                if ($f) {
                    $this->setCurrentFont();
                    $cf = $this->currentFont;
                }
                $i = $i + $directive - 1;
            } else {
                $char = ord($text[$i]);
                if (isset($this->fonts[$cf]['differences'][$char])) {
                    // then this character is being replaced by another
                    $name = $this->fonts[$cf]['differences'][$char];
                    if (isset($this->fonts[$cf]['C'][$name])) {
                        $w += $this->fonts[$cf]['C'][$name];
                    }
                } else if (isset($this->fonts[$cf]['C'][$char])) {
                    $w += $this->fonts[$cf]['C'][$char];
                }
            }
        }

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

        return $w * $size / 1000;
    }

    /**
     * do a part of the calculation for sorting out the justification of the text
     *
     * @access private
     */
    private function adjustWrapText($text, $actual, $width, &$x, &$adjust, $justification) {
        switch ($justification) {
            case 'left':
                return;
                break;
            case 'right':
                $x += $width - $actual;
                break;
            case 'center':
            case 'centre':
                $x += ($width - $actual) / 2;
                break;
            case 'full':
                // count the number of words
                $words = explode(' ', $text);
                $nspaces = count($words) - 1;
                if ($nspaces > 0) {
                    $adjust = ($width - $actual) / $nspaces;
                } else {
                    $adjust = 0;
                }
                break;
        }
    }

    /**
     * add text to the page, but ensure that it fits within a certain width
     * if it does not fit then put in as much as possible, splitting at word boundaries
     * and return the remainder.
     * justification and angle can also be specified for the text
     * @access public
     */
    public function addTextWrap($x, $y, $width, $size, $text, $justification = 'left', $angle = 0, $test = 0) {
        // this will display the text, and if it goes beyond the width $width, will backtrack to the
        // previous space or hyphen, and return the remainder of the text.
        // $justification can be set to 'left','right','center','centre','full'
        // need to store the initial text state, as this will change during the width calculation
        // but will need to be re-set before printing, so that the chars work out right
        $store_currentTextState = $this->currentTextState;

        if (!$this->numFonts) {
            $this->selectFont(dirname(__FILE__) . '/fonts/Helvetica');
        }
        if ($width <= 0) {
            // error, pretend it printed ok, otherwise risking a loop
            return '';
        }
        $w = 0;
        $break = 0;
        $breakWidth = 0;
        $len = strlen($text);
        $cf = $this->currentFont;
        $tw = $width / $size * 1000;
        for ($i = 0; $i < $len; $i++) {
            $f = 1;
            $directive = $this->checkTextDirective($text, $i, $f);
            if ($directive) {
                if ($f) {
                    $this->setCurrentFont();
                    $cf = $this->currentFont;
                }
                $i = $i + $directive - 1;
            } else {
                $cOrd = ord($text[$i]);
                if (isset($this->fonts[$cf]['differences'][$cOrd])) {
                    // then this character is being replaced by another
                    $cOrd2 = $this->fonts[$cf]['differences'][$cOrd];
                } else {
                    $cOrd2 = $cOrd;
                }

                if (isset($this->fonts[$cf]['C'][$cOrd2])) {
                    $w += $this->fonts[$cf]['C'][$cOrd2];
                }
                if ($w > $tw) {
                    // then we need to truncate this line
                    if ($break > 0) {
                        // then we have somewhere that we can split :)
                        if ($text[$break] == ' ') {
                            $tmp = substr($text, 0, $break);
                        } else {
                            $tmp = substr($text, 0, $break + 1);
                        }
                        $adjust = 0;
                        $this->adjustWrapText($tmp, $breakWidth, $width, $x, $adjust, $justification);

                        // reset the text state
                        $this->currentTextState = $store_currentTextState;
                        $this->setCurrentFont();
                        if (!$test) {
                            $this->addText($x, $y, $size, $tmp, $angle, $adjust);
                        }
                        return substr($text, $break + 1);
                    } else {
                        // just split before the current character
                        $tmp = substr($text, 0, $i);
                        $adjust = 0;
                        $ctmp = ord($text[$i]);
                        if (isset($this->fonts[$cf]['differences'][$ctmp])) {
                            $ctmp = $this->fonts[$cf]['differences'][$ctmp];
                        }
                        $tmpw = ($w - $this->fonts[$cf]['C'][$ctmp]) * $size / 1000;
                        $this->adjustWrapText($tmp, $tmpw, $width, $x, $adjust, $justification);
                        // reset the text state
                        $this->currentTextState = $store_currentTextState;
                        $this->setCurrentFont();
                        if (!$test) {
                            $this->addText($x, $y, $size, $tmp, $angle, $adjust);
                        }
                        return substr($text, $i);
                    }
                }
                if ($text[$i] == '-') {
                    $break = $i;
                    $breakWidth = $w * $size / 1000;
                }
                if ($text[$i] == ' ') {
                    $break = $i;
                    $ctmp = ord($text[$i]);
                    if (isset($this->fonts[$cf]['differences'][$ctmp])) {
                        $ctmp = $this->fonts[$cf]['differences'][$ctmp];
                    }
                    $breakWidth = ($w - $this->fonts[$cf]['C'][$ctmp]) * $size / 1000;
                }
            }
        }
        // then there was no need to break this line
        if ($justification == 'full') {
            $justification = 'left';
        }
        $adjust = 0;
        $tmpw = $w * $size / 1000;
        $this->adjustWrapText($text, $tmpw, $width, $x, $adjust, $justification);
        // reset the text state
        $this->currentTextState = $store_currentTextState;
        $this->setCurrentFont();
        if (!$test) {
            $this->addText($x, $y, $size, $text, $angle, $adjust, $angle);
        }
        return '';
    }

    /**
     * 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
     * @access public
     */
    public 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']['r'], $opt['col']['g'], $opt['col']['b'], 1);
            $this->setStrokeColor($opt['str']['r'], $opt['str']['g'], $opt['str']['b'], 1);
            $this->objects[$this->currentContents]['c'] .= "\n" . $opt['lin'];
            // $this->currentLineStyle = $opt['lin'];
        } else {
            $this->nStateStack++;
            $this->stateStack[$this->nStateStack] = array(
                'col' => $this->currentColour
                , 'str' => $this->currentStrokeColour
                , 'lin' => $this->currentLineStyle
            );
        }
        $this->objects[$this->currentContents]['c'] .= "\nq";
    }

    /**
     * restore a previously saved state
     * @access public
     */
    public function restoreState($pageEnd = 0) {
        if (!$pageEnd) {
            $n = $this->nStateStack;
            $this->currentColour = $this->stateStack[$n]['col'];
            $this->currentStrokeColour = $this->stateStack[$n]['str'];
            $this->objects[$this->currentContents]['c'] .= "\n" . $this->stateStack[$n]['lin'];
            $this->currentLineStyle = $this->stateStack[$n]['lin'];
            unset($this->stateStack[$n]);
            $this->nStateStack--;
        }
        $this->objects[$this->currentContents]['c'] .= "\nQ";
    }

    /**
     * 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
     * @access public
     */
    public 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
     * @access public
     */
    public 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
     * @access public
     */
    public 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
     * @access public
     */
    public 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.
     * @access public
     */
    public 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;
            }
        }
    }

    /**
     * add content to the documents info object
     * @access public
     */
    public 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.
     * @access public
     */
    public 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
     *
     * @access private
     */
    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 = $ret * 256;
            $ret += ord($data[$pos + $i]);
        }
        return $ret;
    }

    /**
     * reads the PNG chunk
     * @param $data - binary part of the png image
     * @access private
     */
    private function readPngChunks(&$data) {
        $default = array('info' => array(), 'transparency' => null, 'idata' => null, 'pdata' => null, 'haveHeader' => false);
        // set pointer
        $p = 8;
        $len = strlen($data);
        // cycle through the file, identifying chunks
        while ($p < $len) {
            $chunkLen = $this->getBytes($data, $p, 4);
            $chunkType = substr($data, $p + 4, 4);
            //error_log($chunkType. ' - '.$chunkLen);
            switch ($chunkType) {
                case 'IHDR':
                    //this is where all the file information comes from
                    $default['info']['width'] = $this->getBytes($data, $p + 8, 4);
                    $default['info']['height'] = $this->getBytes($data, $p + 12, 4);
                    $default['info']['bitDepth'] = ord($data[$p + 16]);
                    $default['info']['colorType'] = ord($data[$p + 17]);
                    $default['info']['compressionMethod'] = ord($data[$p + 18]);
                    $default['info']['filterMethod'] = ord($data[$p + 19]);
                    $default['info']['interlaceMethod'] = ord($data[$p + 20]);

                    $this->debug('readPngChunks: ColorType is' . $default['info']['colorType'], E_USER_NOTICE);

                    $default['haveHeader'] = true;

                    if ($default['info']['compressionMethod'] != 0) {
                        $error = true;
                        $errormsg = "unsupported compression method";
                    }
                    if ($default['info']['filterMethod'] != 0) {
                        $error = true;
                        $errormsg = "unsupported filter method";
                    }

                    $default['transparency'] = array('type' => null, 'data' => null);

                    if ($default['info']['colorType'] == 3) { // indexed color, rbg
                        // 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)
                        $default['transparency']['type'] = 'indexed';
                        //$numPalette = strlen($default['pdata'])/3;
                        $trans = 0;
                        for ($i = $chunkLen; $i >= 0; $i--) {
                            if (ord($data[$p + 8 + $i]) == 0) {
                                $trans = $i;
                            }
                        }
                        $default['transparency']['data'] = $trans;
                    } elseif ($default['info']['colorType'] == 0) { // grayscale
                        // corresponding to entries in the plte chunk
                        // Gray: 2 bytes, range 0 .. (2^bitdepth)-1
                        // $transparency['grayscale']=$this->getBytes($data,$p+8,2); // g = grayscale
                        $default['transparency']['type'] = 'indexed';
                        $default['transparency']['data'] = ord($data[$p + 8 + 1]);
                    } elseif ($default['info']['colorType'] == 2) { // truecolor
                        // 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
                        $default['transparency']['r'] = $this->getBytes($data, $p + 8, 2); // r from truecolor
                        $default['transparency']['g'] = $this->getBytes($data, $p + 10, 2); // g from truecolor
                        $default['transparency']['b'] = $this->getBytes($data, $p + 12, 2); // b from truecolor
                    } else if ($default['info']['colorType'] == 6 || $default['info']['colorType'] == 4) {
                        // set transparency type to "alpha" and proceed with it in $this->o_image later
                        $default['transparency']['type'] = 'alpha';

                        $img = imagecreatefromstring($data);

                        $imgalpha = imagecreate($default['info']['width'], $default['info']['height']);
                        // generate gray scale palette (0 -> 255)
                        for ($c = 0; $c < 256; ++$c) {
                            ImageColorAllocate($imgalpha, $c, $c, $c);
                        }
                        // extract alpha channel
                        for ($xpx = 0; $xpx < $default['info']['width']; ++$xpx) {
                            for ($ypx = 0; $ypx < $default['info']['height']; ++$ypx) {
                                $colorBits = imagecolorat($img, $xpx, $ypx);
                                $color = imagecolorsforindex($img, $colorBits);
                                $color['alpha'] = (((127 - $color['alpha']) / 127) * 255);
                                imagesetpixel($imgalpha, $xpx, $ypx, $color['alpha']);
                            }
                        }
                        $tmpfile_alpha = tempnam($this->tempPath, 'ezImg');

                        imagepng($imgalpha, $tmpfile_alpha);
                        imagedestroy($imgalpha);

                        $alphaData = file_get_contents($tmpfile_alpha);
                        // nested method call to receive info on alpha image
                        $alphaImg = $this->readPngChunks($alphaData);
                        // use 'pdate' to fill alpha image as "palette". But it s the alpha channel
                        $default['pdata'] = $alphaImg['idata'];

                        // generate true color image with no alpha channel
                        $tmpfile_tt = tempnam($this->tempPath, 'ezImg');

                        $imgplain = imagecreatetruecolor($default['info']['width'], $default['info']['height']);
                        imagecopy($imgplain, $img, 0, 0, 0, 0, $default['info']['width'], $default['info']['height']);
                        imagepng($imgplain, $tmpfile_tt);
                        imagedestroy($imgplain);

                        $ttData = file_get_contents($tmpfile_tt);
                        $ttImg = $this->readPngChunks($ttData);

                        $default['idata'] = $ttImg['idata'];

                        // remove temp files 
                        unlink($tmpfile_alpha);
                        unlink($tmpfile_tt);
                        // return to addPngImage prematurely. IDAT has already been read and PLTE is not required
                        return $default;
                    }
                    break;
                case 'PLTE':
                    $default['pdata'] = substr($data, $p + 8, $chunkLen);
                    break;
                case 'IDAT':
                    $default['idata'] .= substr($data, $p + 8, $chunkLen);
                    break;
                case 'tRNS': // this HEADER info is optional. More info: rfc2083 (http://tools.ietf.org/html/rfc2083)
                    // error_log('OPTIONAL HEADER -tRNS- exist:');
                    // this chunk can only occur once and it must occur after the PLTE chunk and before IDAT chunk
                    // KS End new code
                    break;
                default:
                    break;
            }
            $p += $chunkLen + 12;
        }
        return $default;
    }

    /**
     * add a PNG image into the document, from a file
     * this should work with remote files
     * @access public
     */
    public function addPngFromFile($file, $x, $y, $w = 0, $h = 0) {
        // read in a png file, interpret it, then add to the system
        $error = false;
        $errormsg = "";

        $this->debug('addPngFromFile: opening image ' . $file);

        $data = file_get_contents($file);

        if ($data === false) {
            $this->debug('addPngFromFile: trouble opening file ' . $file, E_USER_WARNING);
            return;
        }

        $header = chr(137) . chr(80) . chr(78) . chr(71) . chr(13) . chr(10) . chr(26) . chr(10);
        if (substr($data, 0, 8) != $header) {
            $this->debug('addPngFromFile: Invalid PNG header for file: ' . $file, E_USER_WARNING);
            return;
        }

        $iChunk = $this->readPngChunks($data);

        if (!$iChunk['haveHeader']) {
            $error = true;
            $errormsg = "information header is missing.";
        }
        if (isset($iChunk['info']['interlaceMethod']) && $iChunk['info']['interlaceMethod']) {
            $error = true;
            $errormsg = "There appears to be no support for interlaced images in pdf.";
        }

        if ($iChunk['info']['bitDepth'] > 8) {
            $error = true;
            $errormsg = "only bit depth of 8 or less is supported.";
        }

        if ($iChunk['info']['colorType'] == 1 || $iChunk['info']['colorType'] == 5 || $iChunk['info']['colorType'] == 7) {
            $error = true;
            $errormsg = 'Unsupported PNG color type: ' . $iChunk['info']['colorType'];
        } else if (isset($iChunk['info'])) {
            switch ($iChunk['info']['colorType']) {
                case 3:
                    $color = 'DeviceRGB';
                    $ncolor = 1;
                    break;
                case 6:
                case 2:
                    $color = 'DeviceRGB';
                    $ncolor = 3;
                    break;
                case 4:
                case 0:
                    $color = 'DeviceGray';
                    $ncolor = 1;
                    break;
            }
        }

        if ($error) {
            $this->debug('addPngFromFile: ' . $errormsg, E_USER_WARNING);
            return;
        }
        if ($w == 0) {
            $w = $h / $iChunk['info']['height'] * $iChunk['info']['width'];
        }
        if ($h == 0) {
            $h = $w * $iChunk['info']['height'] / $iChunk['info']['width'];
        }

        if ($this->hashed) {
            $oHash = md5($iChunk['idata']);
        }
        if (isset($oHash) && isset($this->objectHash[$oHash])) {
            $label = $this->objectHash[$oHash];
        } else {
            $this->numImages++;
            $label = 'I' . $this->numImages;
            $this->numObj++;

            if (isset($oHash)) {
                $this->objectHash[$oHash] = $label;
            }

            $options = array('label' => $label, 'data' => $iChunk['idata'], 'bitsPerComponent' => $iChunk['info']['bitDepth'], 'pdata' => $iChunk['pdata']
                , 'iw' => $iChunk['info']['width'], 'ih' => $iChunk['info']['height'], 'type' => 'png', 'color' => $color, 'ncolor' => $ncolor);
            if (isset($iChunk['transparency'])) {
                $options['transparency'] = $iChunk['transparency'];
            }
            $this->o_image($this->numObj, 'new', $options);
        }

        $this->objects[$this->currentContents]['c'] .= "\nq " . sprintf('%.3F', $w) . " 0 0 " . sprintf('%.3F', $h) . " " . sprintf('%.3F', $x) . " " . sprintf('%.3F', $y) . " cm";
        $this->objects[$this->currentContents]['c'] .= " /" . $label . ' Do';
        $this->objects[$this->currentContents]['c'] .= " Q";
    }

    /**
     * add a JPEG image into the document, from a file
     * @access public
     */
    public 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;
        }

        $tmp = getimagesize($img);
        $imageWidth = $tmp[0];
        $imageHeight = $tmp[1];

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

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

        $data = file_get_contents($img);

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

    /**
     * read gif image from file, converts it into an JPEG (no transparancy) and display it
     * @param $img - file path ti gif image
     * @param $x - coord x
     * @param $y - y cord
     * @param $w - width
     * @param $h - height
     * @access public
     */
    public function addGifFromFile($img, $x, $y, $w = 0, $h = 0) {
        if (!file_exists($img)) {
            return;
        }

        if (!function_exists("imagecreatefromgif")) {
            $this->debug('addGifFromFile: Missing GD function imageCreateFromGif', E_USER_ERROR);
            return;
        }

        $tmp = getimagesize($img);
        $imageWidth = $tmp[0];
        $imageHeight = $tmp[1];


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

        $imgres = imagecreatefromgif($img);
        $tmpName = tempnam($this->tempPath, 'img');
        imagejpeg($imgres, $tmpName, 90);

        $this->addJpegFromFile($tmpName, $x, $y, $w, $h);
    }

    /**
     * add an image into the document, from a GD object
     * this function is not all that reliable, and I would probably encourage people to use
     * the file based functions
     * @param $img - gd image resource
     * @param $x coord x
     * @param $y coord y
     * @param $w width
     * @param $h height
     * @param $quality image quality
     * @access protected
     */
    protected function addImage(&$img, $x, $y, $w = 0, $h = 0, $quality = 75) {
        // add a new image into the current location, as an external object
        // add the image at $x,$y, and with width and height as defined by $w & $h
        // note that this will only work with full colour images and makes them jpg images for display
        // later versions could present lossless image formats if there is interest.
        // there seems to be some problem here in that images that have quality set above 75 do not appear
        // not too sure why this is, but in the meantime I have restricted this to 75.
        if ($quality > 75) {
            $quality = 75;
        }

        // if the width or height are set to zero, then set the other one based on keeping the image
        // height/width ratio the same, if they are both zero, then give up :)
        $imageWidth = imagesx($img);
        $imageHeight = imagesy($img);

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

        $tmpName = tempnam($this->tempPath, 'img');
        imagejpeg($img, $tmpName, $quality);

        $data = file_get_contents($tmpName);
        if ($data === false) {
            $this->debug('addImage: trouble opening image resource', E_USER_WARNING);
        }
        unlink($tmpName);
        $this->addJpegImage_common($data, $x, $y, $w, $h, $imageWidth, $imageHeight);
    }

    /**
     * common code used by the two JPEG adding functions
     * @access private
     */
    private function addJpegImage_common(&$data, $x, $y, $w = 0, $h = 0, $imageWidth, $imageHeight, $channels = 3) {
        // note that this function is not to be called externally
        // it is just the common code between the GD and the file options
        if ($this->hashed) {
            $oHash = md5($data);
        }
        if (isset($oHash) && isset($this->objectHash[$oHash])) {
            $label = $this->objectHash[$oHash];
        } else {
            $this->numImages++;
            $label = 'I' . $this->numImages;
            $this->numObj++;

            if (isset($oHash)) {
                $this->objectHash[$oHash] = $label;
            }

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

        $this->objects[$this->currentContents]['c'] .= "\nq " . sprintf('%.3F', $w) . " 0 0 " . sprintf('%.3F', $h) . " " . sprintf('%.3F', $x) . " " . sprintf('%.3F', $y) . " cm";
        $this->objects[$this->currentContents]['c'] .= " /" . $label . ' Do';
        $this->objects[$this->currentContents]['c'] .= " Q";
    }

    /**
     * specify where the document should open when it first starts
     * @access public
     */
    public 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);
    }

    /**
     * create a labelled destination within the document
     * @access public
     */
    public 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.
     * @access public
     */
    public function setFontFamily($family, $options = '') {
        if (is_array($options)) {
            // 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 (strlen($family)) {
                $this->fontFamilies[$family] = $options;
            }
        }
    }

    /**
     * used to add messages for use in debugging
     * @access protected
     */
    protected function debug($message, $error_type = E_USER_NOTICE) {
        if ($error_type <= $this->DEBUGLEVEL) {
            switch (strtolower($this->DEBUG)) {
                default:
                case 'none':
                    break;
                case 'error_log':
                    trigger_error($message, $error_type);
                    break;
                case 'variable':
                    $this->messages .= $message . "\n";
                    break;
            }
        }
    }

    /**
     * a few functions which should allow the document to be treated transactionally.
     *
     * @param string $action WHAT IS THIS?
     * @return void
     * @access protected
     */
    public function transaction($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;
        }
    }

}

// end of class
?>