<?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: Cmap.php 20096 2010-01-06 02:05:09Z bkarwin $

 */

/**

 * Abstract helper class for {@link Zend_Pdf_Resource_Font} which manages font

 * character maps.

 *

 * Defines the public interface for concrete subclasses which are responsible

 * for mapping Unicode characters to the font's glyph numbers. Also provides

 * shared utility methods.

 *

 * Cmap objects should ordinarily be obtained through the factory method

 * {@link cmapWithTypeData()}.

 *

 * The supported character map types are those found in the OpenType spec. For

 * additional detail on the internal binary format of these tables, see:

 * <ul>

 *  <li>{@link http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6cmap.html}

 *  <li>{@link http://www.microsoft.com/OpenType/OTSpec/cmap.htm}

 *  <li>{@link http://partners.adobe.com/public/developer/opentype/index_cmap.html}

 * </ul>

 *

 * @todo Write code for Zend_Pdf_FontCmap_HighByteMapping class.

 * @todo Write code for Zend_Pdf_FontCmap_MixedCoverage class.

 * @todo Write code for Zend_Pdf_FontCmap_TrimmedArray class.

 * @todo Write code for Zend_Pdf_FontCmap_SegmentedCoverage class.

 *

 * @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

 */

abstract class Zend_Pdf_Cmap

{

  /**** Class Constants ****/

  /* Cmap Table Types */

    /**

     * Byte Encoding character map table type.

     */

    const TYPE_BYTE_ENCODING = 0x00;

    /**

     * High Byte Mapping character map table type.

     */

    const TYPE_HIGH_BYTE_MAPPING = 0x02;

    /**

     * Segment Value to Delta Mapping character map table type.

     */

    const TYPE_SEGMENT_TO_DELTA = 0x04;

    /**

     * Trimmed Table character map table type.

     */

    const TYPE_TRIMMED_TABLE = 0x06;

    /**

     * Mixed Coverage character map table type.

     */

    const TYPE_MIXED_COVERAGE = 0x08;

    /**

     * Trimmed Array character map table type.

     */

    const TYPE_TRIMMED_ARRAY = 0x0a;

    /**

     * Segmented Coverage character map table type.

     */

    const TYPE_SEGMENTED_COVERAGE = 0x0c;

    /**

     * Static Byte Encoding character map table type. Variant of

     * {@link TYPE_BYTEENCODING}.

     */

    const TYPE_BYTE_ENCODING_STATIC = 0xf1;

    /**

     * Unknown character map table type.

     */

    const TYPE_UNKNOWN = 0xff;

  /* Special Glyph Names */

    /**

     * Glyph representing missing characters.

     */

    const MISSING_CHARACTER_GLYPH = 0x00;

  /**** Public Interface ****/

  /* Factory Methods */

    /**

     * Instantiates the appropriate concrete subclass based on the type of cmap

     * table and returns the instance.

     *

     * The cmap type must be one of the following values:

     * <ul>

     *  <li>{@link Zend_Pdf_Cmap::TYPE_BYTE_ENCODING}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_BYTE_ENCODING_STATIC}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_HIGH_BYTE_MAPPING}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_SEGMENT_TO_DELTA}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_TRIMMED_TABLE}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_MIXED_COVERAGE}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_TRIMMED_ARRAY}

     *  <li>{@link Zend_Pdf_Cmap::TYPE_SEGMENTED_COVERAGE}

     * </ul>

     *

     * Throws an exception if the table type is invalid or the cmap table data

     * cannot be validated.

     *

     * @param integer $cmapType Type of cmap.

     * @param mixed $cmapData Cmap table data. Usually a string or array.

     * @return Zend_Pdf_Cmap

     * @throws Zend_Pdf_Exception

     */

    public static function cmapWithTypeData($cmapType, $cmapData)

    {

        switch ($cmapType) {

            case Zend_Pdf_Cmap::TYPE_BYTE_ENCODING:

                require_once 'Zend/Pdf/Cmap/ByteEncoding.php';

                return new Zend_Pdf_Cmap_ByteEncoding($cmapData);

            case Zend_Pdf_Cmap::TYPE_BYTE_ENCODING_STATIC:

                require_once 'Zend/Pdf/Cmap/ByteEncoding/Static.php';

                return new Zend_Pdf_Cmap_ByteEncoding_Static($cmapData);

            case Zend_Pdf_Cmap::TYPE_HIGH_BYTE_MAPPING:

                require_once 'Zend/Pdf/Exception.php';

                throw new Zend_Pdf_Exception('High byte mapping cmap currently unsupported',

                                             Zend_Pdf_Exception::CMAP_TYPE_UNSUPPORTED);

            case Zend_Pdf_Cmap::TYPE_SEGMENT_TO_DELTA:

                require_once 'Zend/Pdf/Cmap/SegmentToDelta.php';

                return new Zend_Pdf_Cmap_SegmentToDelta($cmapData);

            case Zend_Pdf_Cmap::TYPE_TRIMMED_TABLE:

                require_once 'Zend/Pdf/Cmap/TrimmedTable.php';

                return new Zend_Pdf_Cmap_TrimmedTable($cmapData);

            case Zend_Pdf_Cmap::TYPE_MIXED_COVERAGE:

                require_once 'Zend/Pdf/Exception.php';

                throw new Zend_Pdf_Exception('Mixed coverage cmap currently unsupported',

                                             Zend_Pdf_Exception::CMAP_TYPE_UNSUPPORTED);

            case Zend_Pdf_Cmap::TYPE_TRIMMED_ARRAY:

                require_once 'Zend/Pdf/Exception.php';

                throw new Zend_Pdf_Exception('Trimmed array cmap currently unsupported',

                                             Zend_Pdf_Exception::CMAP_TYPE_UNSUPPORTED);

            case Zend_Pdf_Cmap::TYPE_SEGMENTED_COVERAGE:

                require_once 'Zend/Pdf/Exception.php';

                throw new Zend_Pdf_Exception('Segmented coverage cmap currently unsupported',

                                             Zend_Pdf_Exception::CMAP_TYPE_UNSUPPORTED);

            default:

                require_once 'Zend/Pdf/Exception.php';

                throw new Zend_Pdf_Exception("Unknown cmap type: $cmapType",

                                             Zend_Pdf_Exception::CMAP_UNKNOWN_TYPE);

        }

    }

  /* Abstract Methods */

    /**

     * Object constructor

     *

     * Parses the raw binary table data. Throws an exception if the table is

     * malformed.

     *

     * @param string $cmapData Raw binary cmap table data.

     * @throws Zend_Pdf_Exception

     */

    abstract public function __construct($cmapData);

    /**

     * Returns an array of glyph numbers corresponding to the Unicode characters.

     *

     * If a particular character doesn't exist in this font, the special 'missing

     * character glyph' will be substituted.

     *

     * See also {@link glyphNumberForCharacter()}.

     *

     * @param array $characterCodes Array of Unicode character codes (code points).

     * @return array Array of glyph numbers.

     */

    abstract public function glyphNumbersForCharacters($characterCodes);

    /**

     * Returns the glyph number corresponding to the Unicode character.

     *

     * If a particular character doesn't exist in this font, the special 'missing

     * character glyph' will be substituted.

     *

     * See also {@link glyphNumbersForCharacters()} which is optimized for bulk

     * operations.

     *

     * @param integer $characterCode Unicode character code (code point).

     * @return integer Glyph number.

     */

    abstract public function glyphNumberForCharacter($characterCode);

    /**

     * Returns an array containing the Unicode characters that have entries in

     * this character map.

     *

     * @return array Unicode character codes.

     */

    abstract public function getCoveredCharacters();

    /**

     * Returns an array containing the glyphs numbers that have entries in this character map.

     * Keys are Unicode character codes (integers)

     *

     * This functionality is partially covered by glyphNumbersForCharacters(getCoveredCharacters())

     * call, but this method do it in more effective way (prepare complete list instead of searching

     * glyph for each character code).

     *

     * @internal

     * @return array Array representing <Unicode character code> => <glyph number> pairs.

     */

    abstract public function getCoveredCharactersGlyphs();

  /**** Internal Methods ****/

  /* Internal Utility Methods */

    /**

     * Extracts a signed 2-byte integer from a string.

     *

     * Integers are always big-endian. Throws an exception if the index is out

     * of range.

     *

     * @param string &$data

     * @param integer $index Position in string of integer.

     * @return integer

     * @throws Zend_Pdf_Exception

     */

    protected function _extractInt2(&$data, $index)

    {

        if (($index < 0) | (($index + 1) > strlen($data))) {

            require_once 'Zend/Pdf/Exception.php';

            throw new Zend_Pdf_Exception("Index out of range: $index",

                                         Zend_Pdf_Exception::INDEX_OUT_OF_RANGE);

        }

        $number = ord($data[$index]);

        if (($number & 0x80) == 0x80) {    // negative

            $number = ~((((~ $number) & 0xff) << 8) | ((~ ord($data[++$index])) & 0xff));

        } else {

            $number = ($number << 8) | ord($data[++$index]);

        }

        return $number;

    }

    /**

     * Extracts an unsigned 2-byte integer from a string.

     *

     * Integers are always big-endian. Throws an exception if the index is out

     * of range.

     *

     * @param string &$data

     * @param integer $index Position in string of integer.

     * @return integer

     * @throws Zend_Pdf_Exception

     */

    protected function _extractUInt2(&$data, $index)

    {

        if (($index < 0) | (($index + 1) > strlen($data))) {

            require_once 'Zend/Pdf/Exception.php';

            throw new Zend_Pdf_Exception("Index out of range: $index",

                                         Zend_Pdf_Exception::INDEX_OUT_OF_RANGE);

        }

        $number = (ord($data[$index]) << 8) | ord($data[++$index]);

        return $number;

    }

    /**

     * Extracts an unsigned 4-byte integer from a string.

     *

     * Integers are always big-endian. Throws an exception if the index is out

     * of range.

     *

     * NOTE: If you ask for a 4-byte unsigned integer on a 32-bit machine, the

     * resulting value WILL BE SIGNED because PHP uses signed integers internally

     * for everything. To guarantee portability, be sure to use bitwise or

     * similar operators on large integers!

     *

     * @param string &$data

     * @param integer $index Position in string of integer.

     * @return integer

     * @throws Zend_Pdf_Exception

     */

    protected function _extractUInt4(&$data, $index)

    {

        if (($index < 0) | (($index + 3) > strlen($data))) {

            require_once 'Zend/Pdf/Exception.php';

            throw new Zend_Pdf_Exception("Index out of range: $index",

                                         Zend_Pdf_Exception::INDEX_OUT_OF_RANGE);

        }

        $number = (ord($data[$index]) << 24) | (ord($data[++$index]) << 16) |

                  (ord($data[++$index]) << 8) | ord($data[++$index]);

        return $number;

    }

}