<?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

 * @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: ElementFactory.php 22797 2010-08-06 15:02:12Z alexander $

 */

/** Zend_Pdf_ElementFactory_Interface */

require_once 'Zend/Pdf/ElementFactory/Interface.php';

/**

 * PDF element factory.

 * Responsibility is to log PDF changes

 *

 * @package    Zend_Pdf

 * @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_ElementFactory implements Zend_Pdf_ElementFactory_Interface

{

    /**

     * List of the modified objects.

     * Also contains new and removed objects

     *

     * Array: ojbectNumber => Zend_Pdf_Element_Object

     *

     * @var array

     */

    private $_modifiedObjects = array();

    /**

     * List of the removed objects

     *

     * Array: ojbectNumber => Zend_Pdf_Element_Object

     *

     * @var SplObjectStorage

     */

    private $_removedObjects;

    /**

     * List of registered objects.

     * Used for resources clean up when factory is destroyed.

     *

     * Array of Zend_Pdf_Element objects

     *

     * @var array

     */

    private $_registeredObjects = array();

    /**

     * PDF object counter.

     * Actually it's an object number for new PDF object

     *

     * @var integer

     */

    private $_objectCount;

    /**

     * List of the attached object factories.

     * Array of Zend_Pdf_ElementFactory_Interface objects

     *

     * @var array

     */

    private $_attachedFactories = array();

    /**

     * Factory internal id

     *

     * @var integer

     */

    private $_factoryId;

    /**

     * Identity, used for factory id generation

     *

     * @var integer

     */

    private static $_identity = 0;

    /**

     * Internal cache to save calculated shifts

     *

     * @var array

     */

    private $_shiftCalculationCache = array();

    /**

     * Object constructor

     *

     * @param integer $objCount

     */

    public function __construct($objCount)

    {

        $this->_objectCount    = (int)$objCount;

        $this->_factoryId      = self::$_identity++;

        $this->_removedObjects = new SplObjectStorage();

    }

    /**

     * Get factory

     *

     * @return Zend_Pdf_ElementFactory_Interface

     */

    public function getFactory()

    {

        return $this;

    }

    /**

     * Factory generator

     *

     * @param integer $objCount

     * @return Zend_Pdf_ElementFactory_Interface

     */

    static public function createFactory($objCount)

    {

        require_once 'Zend/Pdf/ElementFactory/Proxy.php';

        return new Zend_Pdf_ElementFactory_Proxy(new Zend_Pdf_ElementFactory($objCount));

    }

    /**

     * Close factory and clean-up resources

     *

     * @internal

     */

    public function close()

    {

        $this->_modifiedObjects   = null;

        $this->_removedObjects    = null;

        $this->_attachedFactories = null;

        foreach ($this->_registeredObjects as $obj) {

            $obj->cleanUp();

        }

        $this->_registeredObjects = null;

    }

    /**

     * Get source factory object

     *

     * @return Zend_Pdf_ElementFactory

     */

    public function resolve()

    {

        return $this;

    }

    /**

     * Get factory ID

     *

     * @return integer

     */

    public function getId()

    {

        return $this->_factoryId;

    }

    /**

     * Set object counter

     *

     * @param integer $objCount

     */

    public function setObjectCount($objCount)

    {

        $this->_objectCount = (int)$objCount;

    }

    /**

     * Get object counter

     *

     * @return integer

     */

    public function getObjectCount()

    {

        $count = $this->_objectCount;

        foreach ($this->_attachedFactories as $attached) {

            $count += $attached->getObjectCount() - 1; // -1 as "0" object is a special case and shared between factories

        }

        return $count;

    }

    /**

     * Attach factory to the current;

     *

     * @param Zend_Pdf_ElementFactory_Interface $factory

     */

    public function attach(Zend_Pdf_ElementFactory_Interface $factory)

    {

        if ( $factory === $this || isset($this->_attachedFactories[$factory->getId()])) {

            /**

             * Don't attach factory twice.

             * We do not check recusively because of nature of attach operation

             * (Pages are always attached to the Documents, Fonts are always attached

             * to the pages even if pages already use Document level object factory and so on)

             */

            return;

        }

        $this->_attachedFactories[$factory->getId()] = $factory;

    }

    /**

     * Calculate object enumeration shift.

     *

     * @param Zend_Pdf_ElementFactory_Interface $factory

     * @return integer

     */

    public function calculateShift(Zend_Pdf_ElementFactory_Interface $factory)

    {

        if ($factory === $this) {

            return 0;

        }

        if (isset($this->_shiftCalculationCache[$factory->_factoryId])) {

            return $this->_shiftCalculationCache[$factory->_factoryId];

        }

        $shift = $this->_objectCount - 1;

        foreach ($this->_attachedFactories as $subFactory) {

            $subFactoryShift = $subFactory->calculateShift($factory);

            if ($subFactoryShift != -1) {

                // context found

                $this->_shiftCalculationCache[$factory->_factoryId] = $shift + $subFactoryShift;

                return $shift + $subFactoryShift;

            } else {

                $shift += $subFactory->getObjectCount()-1;

            }

        }

        $this->_shiftCalculationCache[$factory->_factoryId] = -1;

        return -1;

    }

    /**

     * Clean enumeration shift cache.

     * Has to be used after PDF render operation to let followed updates be correct.

     */

    public function cleanEnumerationShiftCache()

    {

        $this->_shiftCalculationCache = array();

        foreach ($this->_attachedFactories as $attached) {

            $attached->cleanEnumerationShiftCache();

        }

    }

    /**

     * Retrive object enumeration shift.

     *

     * @param Zend_Pdf_ElementFactory_Interface $factory

     * @return integer

     * @throws Zend_Pdf_Exception

     */

    public function getEnumerationShift(Zend_Pdf_ElementFactory_Interface $factory)

    {

        if (($shift = $this->calculateShift($factory)) == -1) {

            require_once 'Zend/Pdf/Exception.php';

            throw new Zend_Pdf_Exception('Wrong object context');

        }

        return $shift;

    }

    /**

     * Mark object as modified in context of current factory.

     *

     * @param Zend_Pdf_Element_Object $obj

     * @throws Zend_Pdf_Exception

     */

    public function markAsModified(Zend_Pdf_Element_Object $obj)

    {

        if ($obj->getFactory() !== $this) {

            require_once 'Zend/Pdf/Exception.php';

            throw new Zend_Pdf_Exception('Object is not generated by this factory');

        }

        $this->_modifiedObjects[$obj->getObjNum()] = $obj;

    }

    /**

     * Remove object in context of current factory.

     *

     * @param Zend_Pdf_Element_Object $obj

     * @throws Zend_Pdf_Exception

     */

    public function remove(Zend_Pdf_Element_Object $obj)

    {

        if (!$obj->compareFactory($this)) {

            require_once 'Zend/Pdf/Exception.php';

            throw new Zend_Pdf_Exception('Object is not generated by this factory');

        }

        $this->_modifiedObjects[$obj->getObjNum()] = $obj;

        $this->_removedObjects->attach($obj);

    }

    /**

     * Generate new Zend_Pdf_Element_Object

     *

     * @todo Reusage of the freed object. It's not a support of new feature, but only improvement.

     *

     * @param Zend_Pdf_Element $objectValue

     * @return Zend_Pdf_Element_Object

     */

    public function newObject(Zend_Pdf_Element $objectValue)

    {

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

        $obj = new Zend_Pdf_Element_Object($objectValue, $this->_objectCount++, 0, $this);

        $this->_modifiedObjects[$obj->getObjNum()] = $obj;

        return $obj;

    }

    /**

     * Generate new Zend_Pdf_Element_Object_Stream

     *

     * @todo Reusage of the freed object. It's not a support of new feature, but only improvement.

     *

     * @param mixed $objectValue

     * @return Zend_Pdf_Element_Object_Stream

     */

    public function newStreamObject($streamValue)

    {

        require_once 'Zend/Pdf/Element/Object/Stream.php';

        $obj = new Zend_Pdf_Element_Object_Stream($streamValue, $this->_objectCount++, 0, $this);

        $this->_modifiedObjects[$obj->getObjNum()] = $obj;

        return $obj;

    }

    /**

     * Enumerate modified objects.

     * Returns array of Zend_Pdf_UpdateInfoContainer

     *

     * @param Zend_Pdf_ElementFactory_Interface $rootFactory

     * @return array

     */

    public function listModifiedObjects($rootFactory = null)

    {

        if ($rootFactory == null) {

            $rootFactory = $this;

            $shift = 0;

        } else {

            $shift = $rootFactory->getEnumerationShift($this);

        }

        ksort($this->_modifiedObjects);

        $result = array();

        require_once 'Zend/Pdf/UpdateInfoContainer.php';

        foreach ($this->_modifiedObjects as $objNum => $obj) {

            if ($this->_removedObjects->contains($obj)) {

                            $result[$objNum+$shift] = new Zend_Pdf_UpdateInfoContainer($objNum + $shift,

                                                                           $obj->getGenNum()+1,

                                                                           true);

            } else {

                $result[$objNum+$shift] = new Zend_Pdf_UpdateInfoContainer($objNum + $shift,

                                                                           $obj->getGenNum(),

                                                                           false,

                                                                           $obj->dump($rootFactory));

            }

        }

        foreach ($this->_attachedFactories as $factory) {

            $result += $factory->listModifiedObjects($rootFactory);

        }

        return $result;

    }

    /**

     * Register object in the factory

     *

     * It's used to clear "parent object" referencies when factory is closed and clean up resources

     *

     * @param string $refString

     * @param Zend_Pdf_Element_Object $obj

     */

    public function registerObject(Zend_Pdf_Element_Object $obj, $refString)

    {

        $this->_registeredObjects[$refString] = $obj;

    }

    /**

     * Fetch object specified by reference

     *

     * @param string $refString

     * @return Zend_Pdf_Element_Object|null

     */

    public function fetchObject($refString)

    {

        if (!isset($this->_registeredObjects[$refString])) {

            return null;

        }

        return $this->_registeredObjects[$refString];

    }

    /**

     * Check if PDF file was modified

     *

     * @return boolean

     */

    public function isModified()

    {

        if (count($this->_modifiedObjects) != 0) {

            return true;

        }

        foreach ($this->_attachedFactories as $subFactory) {

            if ($subFactory->isModified()) {

                return true;

            }

        }

        return false;

    }

}