<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Pdf

 * @subpackage Fonts

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: FontDescriptor.php 20096 2010-01-06 02:05:09Z bkarwin $

 */

/** Internally used classes */

require_once 'Zend/Pdf/Element/Array.php';

require_once 'Zend/Pdf/Element/Dictionary.php';

require_once 'Zend/Pdf/Element/Name.php';

require_once 'Zend/Pdf/Element/Numeric.php';

/** Zend_Pdf_Font */

require_once 'Zend/Pdf/Font.php';

/**

 * FontDescriptor implementation

 *

 * A font descriptor specifies metrics and other attributes of a simple font or a

 * CIDFont as a whole, as distinct from the metrics of individual glyphs. These font

 * metrics provide information that enables a viewer application to synthesize a

 * substitute font or select a similar font when the font program is unavailable. The

 * font descriptor may also be used to embed the font program in the PDF file.

 *

 * @package    Zend_Pdf

 * @subpackage Fonts

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Pdf_Resource_Font_FontDescriptor

{

    /**

     * Object constructor

     * @throws Zend_Pdf_Exception

     */

    public function __construct()

    {

        require_once 'Zend/Pdf/Exception.php';

        throw new Zend_Pdf_Exception('Zend_Pdf_Resource_Font_FontDescriptor is not intended to be instantiated');

    }

    /**

     * Object constructor

     *

     * The $embeddingOptions parameter allows you to set certain flags related

     * to font embedding. You may combine options by OR-ing them together. See

     * the EMBED_ constants defined in {@link Zend_Pdf_Font} for the list of

     * available options and their descriptions.

     *

     * Note that it is not requried that fonts be embedded within the PDF file

     * to use them. If the recipient of the PDF has the font installed on their

     * computer, they will see the correct fonts in the document. If they don't,

     * the PDF viewer will substitute or synthesize a replacement.

     *

     *

     * @param Zend_Pdf_Resource_Font $font Font

     * @param Zend_Pdf_FileParser_Font_OpenType $fontParser Font parser object containing parsed TrueType file.

     * @param integer $embeddingOptions Options for font embedding.

     * @return Zend_Pdf_Element_Dictionary

     * @throws Zend_Pdf_Exception

     */

    static public function factory(Zend_Pdf_Resource_Font $font, Zend_Pdf_FileParser_Font_OpenType $fontParser, $embeddingOptions)

    {

        /* The font descriptor object contains the rest of the font metrics and

         * the information about the embedded font program (if applicible).

         */

        $fontDescriptor = new Zend_Pdf_Element_Dictionary();

        $fontDescriptor->Type     = new Zend_Pdf_Element_Name('FontDescriptor');

        $fontDescriptor->FontName = new Zend_Pdf_Element_Name($font->getResource()->BaseFont->value);

        /* The font flags value is a bitfield that describes the stylistic

         * attributes of the font. We will set as many of the bits as can be

         * determined from the font parser.

         */

        $flags = 0;

        if ($fontParser->isMonospaced) {    // bit 1: FixedPitch

            $flags |= 1 << 0;

        }

        if ($fontParser->isSerifFont) {    // bit 2: Serif

            $flags |= 1 << 1;

        }

        if (! $fontParser->isAdobeLatinSubset) {    // bit 3: Symbolic

            $flags |= 1 << 2;

        }

        if ($fontParser->isScriptFont) {    // bit 4: Script

            $flags |= 1 << 3;

        }

        if ($fontParser->isAdobeLatinSubset) {    // bit 6: Nonsymbolic

            $flags |= 1 << 5;

        }

        if ($fontParser->isItalic) {    // bit 7: Italic

            $flags |= 1 << 6;

        }

        // bits 17-19: AllCap, SmallCap, ForceBold; not available

        $fontDescriptor->Flags = new Zend_Pdf_Element_Numeric($flags);

        $fontBBox = array(new Zend_Pdf_Element_Numeric($font->toEmSpace($fontParser->xMin)),

                          new Zend_Pdf_Element_Numeric($font->toEmSpace($fontParser->yMin)),

                          new Zend_Pdf_Element_Numeric($font->toEmSpace($fontParser->xMax)),

                          new Zend_Pdf_Element_Numeric($font->toEmSpace($fontParser->yMax)));

        $fontDescriptor->FontBBox     = new Zend_Pdf_Element_Array($fontBBox);

        $fontDescriptor->ItalicAngle  = new Zend_Pdf_Element_Numeric($fontParser->italicAngle);

        $fontDescriptor->Ascent       = new Zend_Pdf_Element_Numeric($font->toEmSpace($fontParser->ascent));

        $fontDescriptor->Descent      = new Zend_Pdf_Element_Numeric($font->toEmSpace($fontParser->descent));

        $fontDescriptor->CapHeight    = new Zend_Pdf_Element_Numeric($fontParser->capitalHeight);

        /**

         * The vertical stem width is not yet extracted from the OpenType font

         * file. For now, record zero which is interpreted as 'unknown'.

         * @todo Calculate value for StemV.

         */

        $fontDescriptor->StemV        = new Zend_Pdf_Element_Numeric(0);

        $fontDescriptor->MissingWidth = new Zend_Pdf_Element_Numeric($fontParser->glyphWidths[0]);

        /* Set up font embedding. This is where the actual font program itself

         * is embedded within the PDF document.

         *

         * Note that it is not requried that fonts be embedded within the PDF

         * document to use them. If the recipient of the PDF has the font

         * installed on their computer, they will see the correct fonts in the

         * document. If they don't, the PDF viewer will substitute or synthesize

         * a replacement.

         *

         * There are several guidelines for font embedding:

         *

         * First, the developer might specifically request not to embed the font.

         */

        if (!($embeddingOptions & Zend_Pdf_Font::EMBED_DONT_EMBED)) {

            /* Second, the font author may have set copyright bits that prohibit

             * the font program from being embedded. Yes this is controversial,

             * but it's the rules:

             *   http://partners.adobe.com/public/developer/en/acrobat/sdk/FontPolicies.pdf

             *

             * To keep the developer in the loop, and to prevent surprising bug

             * reports of "your PDF doesn't have the right fonts," throw an

             * exception if the font cannot be embedded.

             */

            if (! $fontParser->isEmbeddable) {

                /* This exception may be suppressed if the developer decides that

                 * it's not a big deal that the font program can't be embedded.

                 */

                if (!($embeddingOptions & Zend_Pdf_Font::EMBED_SUPPRESS_EMBED_EXCEPTION)) {

                    $message = 'This font cannot be embedded in the PDF document. If you would like to use '

                             . 'it anyway, you must pass Zend_Pdf_Font::EMBED_SUPPRESS_EMBED_EXCEPTION '

                             . 'in the $options parameter of the font constructor.';

                    require_once 'Zend/Pdf/Exception.php';

                    throw new Zend_Pdf_Exception($message, Zend_Pdf_Exception::FONT_CANT_BE_EMBEDDED);

                }

            } else {

                /* Otherwise, the default behavior is to embed all custom fonts.

                 */

                /* This section will change soon to a stream object data

                 * provider model so that we don't have to keep a copy of the

                 * entire font in memory.

                 *

                 * We also cannot build font subsetting until the data provider

                 * model is in place.

                 */

                $fontFile = $fontParser->getDataSource()->readAllBytes();

                $fontFileObject = $font->getFactory()->newStreamObject($fontFile);

                $fontFileObject->dictionary->Length1 = new Zend_Pdf_Element_Numeric(strlen($fontFile));

                if (!($embeddingOptions & Zend_Pdf_Font::EMBED_DONT_COMPRESS)) {

                    /* Compress the font file using Flate. This generally cuts file

                     * sizes by about half!

                     */

                    $fontFileObject->dictionary->Filter = new Zend_Pdf_Element_Name('FlateDecode');

                }

                if ($fontParser instanceof Zend_Pdf_FileParser_Font_OpenType_Type1 /* not implemented now */) {

                    $fontDescriptor->FontFile  = $fontFileObject;

                } else if ($fontParser instanceof Zend_Pdf_FileParser_Font_OpenType_TrueType) {

                    $fontDescriptor->FontFile2 = $fontFileObject;

                } else {

                    $fontDescriptor->FontFile3 = $fontFileObject;

                }

            }

        }

        return $fontDescriptor;

    }

}